CN102122815B - Ultra high-speed traveling wave direction pilot protection method, device and system for high voltage transmission line - Google Patents

Abstract

The present invention provides a traveling wave direction longitudinal protection method, comprising: separately obtaining the wave head polarity of the initial traveling wave of the current fault on the first side of the high-voltage transmission line and the initial polarity of the power frequency component in the voltage fault traveling wave, And respectively obtain the wave head polarity of the current fault initial traveling wave of the second side of the high-voltage transmission line and the initial polarity of the power frequency component in the voltage fault traveling wave; the wave head polarity of the current fault initial traveling wave of this side and Compare the initial polarity of the power frequency component in the voltage fault traveling wave to determine the fault direction on this side; exchange the fault direction information on the first side with the fault direction information on the second side, and compare the faults between the two sides Direction information to determine whether an internal fault has occurred on the high-voltage transmission line and determine whether the relay protection is activated. The invention also provides a traveling wave direction longitudinal protection device and a traveling wave direction longitudinal protection system, which can be applied to high-voltage transmission lines, and can quickly and accurately detect faults and fault types, and take protective actions.

Description

Ultra-high-speed traveling wave direction longitudinal protection method, device and system for high-voltage transmission lines

technical field

The invention relates to the field of power systems, in particular to a method, device and system for longitudinal protection of high-voltage transmission lines in the direction of ultra-high-speed traveling waves.

Background technique

Traditional relay protection based on power frequency electrical quantities is affected by factors such as distributed capacitive current of high-voltage transmission lines, current transformer saturation, power system oscillation and transition resistance, and cannot accurately detect faults on the line, and the action speed is generally around 20ms .

The current fault traveling wave and voltage fault traveling wave after a high voltage transmission line fault contain a wealth of fault information, which can be used as the basis for fault detection. The voltage fault traveling wave and current fault traveling wave signal after the fault is a signal with a wide spectrum range. The current transformer has good broadband transmission characteristics, which can effectively transmit the current fault traveling wave, and has been successfully applied to Power system traveling wave ranging. However, capacitive voltage transformers commonly used in EHV/UHV power systems cannot effectively transmit and change wide-band voltage fault traveling waves, which is one of the important reasons why no traveling wave protection devices have been put into practical application in power systems. Although capacitive voltage transformers commonly used in EHV/UHV power systems cannot effectively transmit voltage fault traveling waves in a wide frequency band, they can effectively transmit voltage fault traveling wave signals in a small frequency band near the power frequency. The relay protection based on the principle of frequent fault components has been successfully applied in power systems. Therefore, traveling wave protection is not affected by factors such as distributed capacitive current of high-voltage transmission lines, current transformer saturation, power system oscillation and transition resistance. At the same time, due to the high data sampling rate of traveling wave protection, generally hundreds of thousands of Hz, the amount of data collection and data processing are large, and the protection device has high requirements on the speed of data processing, so traveling wave protection is also important for the protection hardware platform. Higher requirements are put forward, and the traditional relay protection hardware platform based on power frequency electrical quantity can no longer meet the needs of traveling wave protection.

Therefore, there is a need for an ultra-high-speed traveling-wave direction longitudinal protection technology for high-voltage transmission lines to realize accurate detection and protection of high-voltage transmission line faults, and provide a hardware foundation for the realization of a traveling-wave protection hardware platform.

Contents of the invention

In view of this, the technical problem to be solved by the present invention is to provide a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection method, a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device, and a high-voltage transmission line ultra-high-speed traveling direction longitudinal protection device. The wave direction longitudinal protection device system can accurately and quickly detect the faults and fault types of high-voltage transmission lines, and take corresponding protection actions in time.

The present invention provides a method for longitudinal protection of ultra-high-speed traveling wave directions of high-voltage transmission lines, including: step 102, respectively obtaining the wave head polarity of the initial traveling wave of the current fault on the first side of the high-voltage transmission line and the center of the voltage fault traveling wave The initial polarity of the power frequency component, and obtain the wave head polarity of the current fault initial traveling wave of the second side of the high-voltage transmission line and the initial polarity of the power frequency component in the voltage fault traveling wave respectively; Step 104, the first side Compare the wave head polarity of the current fault initial traveling wave with the initial polarity of the power frequency component in the voltage fault traveling wave to determine the fault direction on the first side, and compare the wave head of the current fault initial traveling wave on the second side head polarity and the initial polarity of the power frequency component in the voltage fault traveling wave, to determine the fault direction on the second side; and step 106, exchanging the information of the fault direction on the first side and the information, when the fault direction on the first side and the fault direction on the second side are both positive faults, it is determined that an internal fault has occurred on the high-voltage transmission line, and the relay protection outlet is activated; when the fault direction on the first side and the second When any one of the fault directions on the two sides is a reverse fault, it is determined that no internal fault occurs in the high-voltage transmission line, and the relay protection outlet does not act.

In the above technical solution, preferably, step 102 may include: step 1022, collect the voltage traveling wave and current traveling wave on the first side after the high-voltage transmission line fault, and collect the voltage traveling wave and current wave on the second side after the high-voltage transmission line fault Popular wave; step 1024, phase-mode transformation is carried out respectively to the current traveling wave and the voltage traveling wave of the first side collected to obtain the current traveling wave modulus and the voltage traveling wave modulus of the first side, and the collected second side The current traveling wave and the voltage traveling wave are respectively subjected to phase-mode transformation to obtain the current traveling wave modulus and the voltage traveling wave modulus of the second side; step 1026, performing wavelet transformation on the current traveling wave modulus of the first side to obtain the The current wavelet transform coefficient, and according to the current wavelet transform coefficient of the first side, the current wavelet transform modulus maximum value and the modulus maximum value polarity of the first side are obtained, and then the wave head pole of the initial traveling wave of the current fault on the first side is determined properties, and wavelet transform the current traveling wave modulus of the second side to obtain the current wavelet transform coefficient of the second side, and obtain the current wavelet transform modulus maximum of the second side according to the current wavelet transform coefficient of the second side value and modulus maximum polarity, and then determine the wave head polarity of the current fault initial traveling wave of the second side; and step 1028, extract the voltage fault traveling wave component from the voltage traveling wave modulus of the first side, for The wavelet transform of the voltage fault traveling wave is carried out to obtain the voltage fault traveling wave wavelet transform coefficient of the first side, and according to the voltage fault traveling wave wavelet transform coefficient of the first side, the modulus maxima and Modulus maximum polarity, and then determine the initial polarity of the power frequency component in the voltage fault traveling wave on the first side, and extract the voltage fault traveling wave component from the voltage traveling wave modulus on the second side, and analyze the voltage fault traveling wave Wavelet transform of the voltage fault traveling wave wavelet transform on the second side to obtain the voltage fault traveling wave wavelet transform coefficient of the second side, and according to the voltage fault traveling wave wavelet transform coefficient of the first side to obtain the voltage fault traveling wave wavelet transform modulus maxima and modulus maxima Value polarity, and then determine the initial polarity of the power frequency component in the voltage fault traveling wave on the second side.

In the above technical solution, preferably, the basis for judging the fault direction in step 104 is: if the initial polarity of the power frequency component in the voltage fault traveling wave is opposite to the wave head polarity of the current fault initial traveling wave, then the fault direction is Forward fault; if the initial polarity of the power frequency component of the voltage fault traveling wave is the same as the wave head polarity of the initial traveling wave of the current fault, the fault direction is a reverse fault.

In the above technical solution, preferably, in step 106, the information on the fault direction on the first side and the information on the fault direction on the second side are exchanged through Ethernet optical fiber communication.

The present invention also provides a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device, which is installed on one side of the high-voltage transmission line and may include: a converter, a traveling wave protector, a monitor and an outlet relay, wherein the converter , connected to the traveling wave protector, which converts the first voltage and current from the high-voltage transmission line into the second voltage and current for the traveling wave protection board; the traveling wave protector, connected to the monitor, receives the The second voltage and current of the converter, process the second voltage and current to determine the fault information of the high-voltage transmission line, transmit the fault information to the monitor, send the fault information to the outside and receive other fault information from the outside, Compare the fault information determined by the traveling wave protector with other fault information from the outside, and judge whether to trip and the phase of tripping according to the comparison results. The fault information includes the fault direction and fault phase; the monitor is connected to the traveling wave protector , display and store the fault information transmitted by the traveling wave protector, monitor the traveling wave protector according to the input preset information, and transmit the fault information to the outside; Determines if a trip command is issued.

In the above technical solution, preferably, the monitor may include: a microprocessor, connected to the first CAN communication module, receiving fault information from the traveling wave protector and input information from the keyboard module, and transmitting the input information of the keyboard module To the traveling wave protector, to control the display content of the liquid crystal display module; the first CAN communication module, connected to the microprocessor, to realize the information interaction with the traveling wave protector; the Ethernet communication module, to receive the fault information from the traveling wave protector , to transmit fault information to the outside; the serial port module, connected to the microprocessor, transmits display content and debugging signals; the liquid crystal display module, connected to the microprocessor, displays the display content from the microprocessor and the information input through the keyboard module; The keyboard module is used to input external information; the first FLASH memory is used to store the control program and fault information of the microprocessor; and the first SDAM memory is used to store the intermediate data processed by the microprocessor; wherein the microprocessor can also Including: the inspection module, connected to the first CAN communication module, regularly inspects the traveling wave protector through the first CAN communication module, and sends an alarm message when the inspection finds an abnormal state; the upload module, connected to the first CAN communication module , receive the fault information from the traveling wave protector through the first CAN communication module, and save it in the FLASH memory; the download module, connected to the first CAN communication module, reset the protection setting set by the user through the first CAN communication module The value is sent to the traveling wave protector.

In the above technical solution, preferably, the traveling wave protector may include: a traveling wave data acquisition module, a traveling wave data processing module, and an information input and output module, wherein the traveling wave data acquisition module includes: a core control module, a second-order active Source low-pass filter module, second-order passive band-pass filter module, protection hardware start-up module, multiplexer switch module, A/D conversion module, dual-port RAM module, among which the second-order active low-pass filter module receives high-voltage The traveling wave analog signal of the transmission line is used to filter the traveling wave analog signal. The traveling wave analog signal includes the voltage traveling wave analog signal and the current traveling wave analog signal; the second-order passive band-pass filter module is connected to the second-order active low-pass The filter module is used to extract the high-frequency signal in the traveling wave from the output signal of the second-order active low-pass filter module; the protection hardware startup module receives the high-frequency signal from the second-order passive band-pass filter module, and determines Whether the high-frequency signal meets the predetermined condition, after the high-frequency signal meets the predetermined condition, send the start signal to the core control module; the multiplexer switch module is connected to the second-order active low-pass filter module, and is used to receive the signal from the core control After the control signal of the module, the traveling wave analog signal is sequentially output to the A/D conversion module; the A/D conversion module is connected to the multi-channel conversion switch module, and performs A/D on the traveling wave analog signal according to the control signal from the core control module. Convert, and output the conversion result to the dual-port RAM module; the dual-port RAM module has two sets of data buses and two sets of address buses, and is used to store the conversion result from the A/D conversion module under the control of the core control module, and The conversion result is read by the traveling wave data processing module; and the core control module receives the start signal from the protection hardware start module, controls the multiplex switch, the A/D converter, and the dual-port RAM, and realizes the address bus and data Decoding of the bus, and sending an interrupt signal to the traveling wave data processing module; the traveling wave data processing module receives the interrupt signal from the core control module, reads the conversion result from the dual-port RAM, and processes the conversion result to obtain the fault information, Among them, the fault information includes the fault direction and fault phase of the high-voltage transmission line; the information input and output modules include: information processing module, Ethernet control module, switch input module, switch output module, among them, the information processing module receives from The fault information of the traveling wave data processing module receives other fault information from the other side of the high-voltage transmission line through the Ethernet control module, and receives the switching value information from the switching value input module, according to the fault information from the traveling wave data processing module , Other fault information from the other side and switch value information to determine whether to trip or not; the Ethernet control module sends the fault information from the information processing module to the traveling wave direction protection device on the other side of the high-voltage transmission line, And receiving other fault information sent from the traveling wave protection device on the other side, and sending the other fault information to the information processing module; the switching value input module is used to input the switching value information used by the traveling wave protection device to the information processing module; and Switching output module, receiving The command for tripping from the information processing module is different from the tripping and sent to the exit relay; the second CAN communication module receives the fault report information from the information processing module and sends it to the monitor; and the 232 communication module receives the pair from the monitor Debug signal for debugging of the traveling wave protector.

In the above technical solution, preferably, the traveling wave data processing module includes: a phase-mode transformation module, a wavelet transformation module, a fault start discrimination module, a traveling wave fault phase selection module, and a polarity comparison traveling wave direction relay module, wherein the phase-mode transformation module , Carry out Karen Bell transform on the conversion result from the dual-port RAM to obtain the modulus traveling wave data; the wavelet transform module receives the modulus traveling wave data from the phase-mode transform module, and performs wavelet transform on the modulus traveling wave data to obtain the wavelet transform The modulus maximum value and the polarity of the modulus maximum value, and obtain the wave head polarity of the fault initial traveling wave according to the polarity of the modulus maximum value; the fault start discrimination module receives the modulus maximum value from the wavelet transform module, According to the singularity detection theory of Lipschitz signal, it is determined whether the line fault causes the start-up of the protection hardware start-up module, and only when it is determined that the line fault causes the start-up of the protection hardware start-up module, start the traveling wave fault phase selection module and the polarity comparison. The wave direction relay module; the traveling wave fault phase selection module receives the modulus maximum value from the wavelet transform module, and confirms the fault type and fault phase of the line according to the modulus maximum value; the polarity comparison traveling wave direction relay module receives The wave head polarity of the fault initial traveling wave from the wavelet transform module, and confirm the fault direction of the line according to the wave head polarity of the fault initial traveling wave, and confirm whether to send the fault direction and fault phase difference information according to the fault direction on the line Input and output modules.

In the above technical solution, preferably, the traveling wave data processing module may further include: a second SDRAM memory for storing the data required for processing by the traveling wave data processing module; a second FLASH memory for storing the data for processing the traveling wave data The algorithm program adopted by the module; and the SPI communication control module enable the traveling wave data processing module to perform SPI communication with the information input and output module, and send the fault information to the information input and output module.

The present invention also provides a longitudinal protection system for ultra-high-speed traveling wave direction of high-voltage transmission lines. The first side of the high-voltage transmission line is provided with the above-mentioned first ultra-high-speed traveling wave direction longitudinal protection device for high-voltage transmission lines, the first voltage The transformer, the first current transformer, the first circuit breaker and the first Ethernet communication device, and the second side of the high-voltage transmission line are provided with the above-mentioned second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device, the second Two voltage transformers, a second current transformer, a second circuit breaker and a second Ethernet communication device, wherein the first voltage transformer and the second voltage transformer convert the voltage on the high-voltage transmission line into the first The voltage of a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device and the second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device; the first current transformer and the second current transformer, the current on the high-voltage transmission line converted into currents respectively provided to the first high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device and the second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device; the first high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device A device for obtaining the wave head polarity of the current fault initial traveling wave and the power frequency of the voltage fault traveling wave on the first side of the high-voltage transmission line from the voltage and current from the first voltage transformer and the first current transformer respectively The initial polarity of the component, and determine the fault direction of the first side of the high-voltage transmission line according to the wave head polarity of the initial traveling wave of the current fault on the first side and the initial polarity of the power frequency component in the voltage fault traveling wave, and through the Ethernet The communication device receives other fault information from the ultra-high-speed traveling wave direction longitudinal protection device of the second high-voltage transmission line on the second side, and determines the fault of the high-voltage transmission line according to the fault information on the first side and other fault information on the second side type and fault, and determine whether to send a trip command to the first outlet relay; the second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device, from the voltage and current from the second voltage transformer and the second current transformer Obtain the wave head polarity of the initial traveling wave of the current fault on the second side of the high-voltage transmission line and the initial polarity of the power frequency component in the voltage fault traveling wave respectively, and according to the wave head polarity of the initial traveling wave of the current fault on the second side Determine the fault direction of the second side of the high-voltage transmission line based on the initial polarity of the power frequency component in the voltage fault traveling wave, and receive the ultra-high-speed traveling wave direction longitudinal connection of the first high-voltage transmission line from the first side through the Ethernet communication device Other fault information of the protection device, according to the fault information on the second side and other fault information on the first side, determine the fault type and fault phase of the high-voltage transmission line, and determine whether to send a trip command to the second outlet relay; the first Ethernet The network communication device transmits the fault information on the first side of the high-voltage transmission line to the second Ethernet communication device on the second side of the high-voltage transmission line through the optical fiber communication network, so as to realize the interaction of fault information at both ends of the high-voltage transmission line; the second Ethernet The communication device transmits the fault information on the second side of the high-voltage transmission line to the first Ethernet communication device on the first side of the high-voltage transmission line through the optical fiber communication network; the first circuit breaker is installed on the high-voltage transmission line; On the high-voltage transmission line, it receives the trip command from the first high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device to open or close the high-voltage transmission line; and the second circuit breaker, installed on the high-voltage transmission line, receives the trip command from the second The trip command of the traveling wave directional protection device opens or closes the high voltage transmission line.

Description of drawings

Fig. 1 shows the flow chart of the ultra-high-speed traveling wave direction longitudinal protection method for high-voltage transmission lines according to an embodiment of the present invention;

Fig. 2 shows a block diagram of a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device according to an embodiment of the present invention;

3 shows a block diagram of a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection system according to an embodiment of the present invention;

4 shows a schematic diagram of a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection system according to an embodiment of the present invention;

Fig. 5 shows a schematic structural diagram of a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device according to an embodiment of the present invention;

Fig. 6 shows a schematic structural diagram of a traveling wave protector according to an embodiment of the present invention;

Fig. 7 shows the program execution flowchart of the digital processing chip TMS320C6713 according to an embodiment of the present invention;

Fig. 8 shows a schematic diagram of multi-resolution decomposition of wavelet transform according to an embodiment of the present invention;

Fig. 9 shows the program flowchart of the traveling wave fault phase selection module according to an embodiment of the present invention;

Figures 10a and 10b show schematic diagrams of a polarizing current fault traveling wave direction relay according to an embodiment of the present invention;

Fig. 11 shows the program flowchart of microprocessor MCF5282 in the traveling wave protector according to an embodiment of the present invention;

Fig. 12 shows a block diagram of hardware configuration of a monitoring board according to an embodiment of the present invention;

Fig. 13 shows the block diagram of monitoring board embedded system software design according to an embodiment of the present invention;

Figure 14a shows a schematic diagram of an Ethernet optical fiber communication system according to an embodiment of the present invention; and

Fig. 14b shows a schematic diagram of an Ethernet optical fiber communication system according to an embodiment of the present invention.

Detailed ways

In order to understand the above-mentioned purpose, features and advantages of the present invention more clearly, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

In the following description, many specific details are set forth in order to fully understand the present invention, but the present invention can also be implemented in other ways different from those described here, therefore, the present invention is not limited to the specific embodiments disclosed below limit.

Fig. 1 shows a flow chart of a method for longitudinal protection of a high-voltage transmission line in an ultra-high-speed traveling wave direction according to an embodiment of the present invention.

As shown in FIG. 1 , the method for longitudinal protection of high-voltage transmission lines in the direction of ultra-high-speed traveling waves according to an embodiment of the present invention includes: step 102, respectively obtaining the wave head polarity of the initial traveling wave of the current fault on the first side of the high-voltage transmission line and the initial polarity of the power frequency component in the voltage fault traveling wave, and respectively obtain the wave head polarity of the current fault initial traveling wave of the second side of the high voltage transmission line and the initial polarity of the power frequency component in the voltage fault traveling wave; step 104. Comparing the head polarity of the initial traveling wave of the current fault on the first side with the initial polarity of the power frequency component in the voltage fault traveling wave to determine the direction of the fault on the first side, and the current on the second side comparing the wave head polarity of the fault initial traveling wave with the initial polarity of the power frequency component in the voltage fault traveling wave to determine the fault direction on the second side; and step 106, exchanging the information of the fault direction on the first side with the second The fault direction information on the two sides, when the fault direction on the first side and the fault direction on the second side are both positive faults, it is determined that an internal fault has occurred on the high-voltage transmission line, and the relay protection outlet is activated. When any one of the fault direction on the upper side and the fault direction on the second side is a reverse fault, it is determined that no internal fault has occurred on the high-voltage transmission line, and the relay protection outlet does not act.

In the above technical solution, preferably, step 102 may include: step 1022, collect the voltage traveling wave and current traveling wave on the first side after the high-voltage transmission line fault, and collect the voltage traveling wave and current wave on the second side after the high-voltage transmission line fault Popular wave; step 1024, phase-mode transformation is carried out respectively to the current traveling wave and the voltage traveling wave of the first side collected to obtain the current traveling wave modulus and the voltage traveling wave modulus of the first side, and the collected second side The current traveling wave and the voltage traveling wave are respectively subjected to phase-mode transformation to obtain the current traveling wave modulus and the voltage traveling wave modulus of the second side; step 1026, performing wavelet transformation on the current traveling wave modulus of the first side to obtain the The current wavelet transform coefficient, and according to the current wavelet transform coefficient of the first side, the current wavelet transform modulus maximum value and the modulus maximum value polarity of the first side are obtained, and then the wave head pole of the initial traveling wave of the current fault on the first side is determined properties, and wavelet transform the current traveling wave modulus of the second side to obtain the current wavelet transform coefficient of the second side, and obtain the current wavelet transform modulus maximum of the second side according to the current wavelet transform coefficient of the second side value and modulus maximum polarity, and then determine the wave head polarity of the current fault initial traveling wave of the second side; and step 1028, extract the voltage fault traveling wave component from the voltage traveling wave modulus of the first side, for The wavelet transform of the voltage fault traveling wave is carried out to obtain the voltage fault traveling wave wavelet transform coefficient of the first side, and according to the voltage fault traveling wave wavelet transform coefficient of the first side, the modulus maxima and Modulus maximum polarity, and then determine the initial polarity of the power frequency component in the voltage fault traveling wave on the first side, and extract the voltage fault traveling wave component from the voltage traveling wave modulus on the second side, and analyze the voltage fault traveling wave Wavelet transform of the voltage fault traveling wave wavelet transform on the second side to obtain the voltage fault traveling wave wavelet transform coefficient of the second side, and according to the voltage fault traveling wave wavelet transform coefficient of the first side to obtain the voltage fault traveling wave wavelet transform modulus maxima and modulus maxima Value polarity, and then determine the initial polarity of the power frequency component in the voltage fault traveling wave on the second side.

In the above technical solution, preferably, the basis for judging the fault direction in step 104 is: if the initial polarity of the power frequency component in the voltage fault traveling wave is opposite to the wave head polarity of the current fault initial traveling wave, then the fault direction is Forward fault; if the initial polarity of the power frequency component of the voltage fault traveling wave is the same as the wave head polarity of the initial traveling wave of the current fault, the fault direction is a reverse fault.

In the above technical solution, preferably, in step 106, the information on the fault direction on the first side and the information on the fault direction on the second side are exchanged through Ethernet optical fiber communication.

Fig. 2 shows a block diagram of a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device according to an embodiment of the present invention.

As shown in Figure 2, the ultra-high-speed traveling wave direction longitudinal protection device 200 for high-voltage transmission lines according to the embodiment of the present invention is installed on one side of the high-voltage transmission line, and may include: a converter 202, a traveling wave protector 204, a monitoring Converter 206 and outlet relay 208, wherein the converter 202 is connected to the traveling wave protector 204, and converts the first voltage and current from the high-voltage transmission line into the second voltage and current used by the traveling wave protection board; The wave protector 204 is connected to the monitor 206, receives the second voltage and current from the converter 202, processes the second voltage and current to determine the fault information of the high-voltage transmission line, and transmits the fault information to the monitor The device 206 sends fault information to the outside and receives other fault information from the outside, compares the fault information determined by the traveling wave protector 204 with other fault information from the outside, and judges whether it is tripped or not according to the comparison result. The information includes fault direction and fault phase difference; the monitor 206 is connected to the traveling wave protector 204, displays and stores the fault information transmitted by the traveling wave protector 204, monitors the traveling wave protector 204 according to the input preset information, and reports the fault The information is transmitted to the outside; and the traveling wave protector 208 receives the judgment result of the traveling wave protector 204, and determines whether to issue a trip command according to the judgment result.

In the above technical solution, preferably, the monitor 206 may include: a microprocessor 2062, connected to the first CAN communication module 2064, receiving fault information from the traveling wave protector 204 and input information from the keyboard module, and connecting the keyboard module The input information is transmitted to the traveling wave protector 204 to control the display content of the liquid crystal display module; the first CAN communication module 2064 is connected to the microprocessor 2062 to realize information interaction with the traveling wave protector 204; the Ethernet communication module 2066, Receive the fault information from the traveling wave protector 204, and transmit the fault information to the outside; the serial port module, connected to the microprocessor 2062, transmits the display content and debugging signal; the liquid crystal display module 2068, connected to the microprocessor 2062, displays the The display content of the processor 2062 and the information input through the keyboard module; the keyboard module 20610, inputting external information; the first FLASH memory 20612, used to store the control program and fault information of the microprocessor 2062; and the first SDAM memory 20614, It is used to store the intermediate data processed by the microprocessor 2062; wherein, the microprocessor 2062 may also include: an inspection module, connected to the first CAN communication module 2064, and regularly inspects the traveling wave protector 204 through the first CAN communication module 2064 , sending an alarm message when the inspection finds an abnormal state; the upload module is connected to the first CAN communication module 2064, receives the fault information from the traveling wave protector 204 through the first CAN communication module 2064, and stores it in the FLASH memory; The downloading module is connected to the first CAN communication module 2064, and transmits the protection setting reset by the user to the traveling wave protector 204 through the first CAN communication module 2064.

In the above technical solution, preferably, the traveling wave protector 204 may include: a traveling wave data acquisition module 2042, a traveling wave data processing module 2044, and an information input and output module 2046, wherein the traveling wave data acquisition module 2042 may include: a core control Module, second-order active low-pass filter module, second-order passive band-pass filter module, protection hardware startup module, multiplexer switch module, A/D conversion module, dual-port RAM module, among which second-order active low-pass filter The module receives the traveling wave analog signal from the high-voltage transmission line, and filters the traveling wave analog signal. The traveling wave analog signal includes the voltage traveling wave analog signal and the current traveling wave analog signal; the second-order passive bandpass filter module is connected to the second The first-order active low-pass filter module is used to extract the high-frequency signal in the traveling wave from the output signal of the second-order active low-pass filter module; the protection hardware startup module receives the high-frequency signal from the second-order passive band-pass filter module Frequency signal, and determine whether the high-frequency signal meets the predetermined condition, after the high-frequency signal meets the predetermined condition, send the start signal to the core control module; the multiplexer module is connected to the second-order active low-pass filter module, used in the After receiving the control signal from the core control module, the traveling wave analog signal is sequentially output to the A/D conversion module; the A/D conversion module is connected to the multiplex switch module, and the traveling wave analog signal is simulated according to the control signal from the core control module. The signal is A/D converted, and the conversion result is output to the dual-port RAM module; the dual-port RAM module has two sets of data buses and two sets of address buses, which are used to store data from the A/D conversion module under the control of the core control module. The conversion result, and the conversion result is read by the traveling wave data processing module 2044; and the core control module receives the start signal from the protection hardware start module, controls the multiplexer switch, the A/D converter, and the dual-port RAM, and Realize the decoding of address bus and data bus, and send interrupt signal to traveling wave data processing module 2044; Traveling wave data processing module 2044 receives the interrupt signal from core control module, reads conversion result from dual-port RAM, and converts The results are processed to obtain fault information, wherein the fault information includes the fault direction and fault phase of the high-voltage transmission line; the information input and output module 2046 can include: an information processing module, an Ethernet control module, a switch input module, and a switch output module, wherein the information processing module receives the fault information from the traveling wave data processing module 2044, receives other fault information from the other side of the high-voltage transmission line through the Ethernet control module 2, and receives the switching value from the switching value input module information, according to the fault information from the traveling wave data processing module 2044, other fault information from the other side, and switch value information to determine whether to trip and trip; the Ethernet control module sends the fault information from the information processing module to The traveling wave direction protection device on the other side of the high-voltage transmission line receives other fault information sent from the traveling wave direction protection device on the other side, and sends other fault information to the information processing module block; a switch input module, which inputs the switch information used by the traveling wave protection device to the information processing module; and a switch output module, which receives the tripping command and the trip phase difference from the information processing module and sends it to the traveling wave protector 208 ; the second CAN communication module receives the fault report information from the information processing module and sends it to the monitor 206 ; and 232 the communication module receives the debugging signal for debugging the traveling wave protector 204 from the monitor 206 .

In the above technical solution, preferably, the traveling wave data processing module 2044 includes: a phase-mode transformation module, a wavelet transformation module, a fault start discrimination module, a traveling-wave fault phase selection module, and a polarity comparison type traveling-wave direction relay module, wherein the phase-mode transformation module, which performs Karen Bell transform on the conversion result from the dual-port RAM to obtain the modulus traveling wave data; the wavelet transform module receives the modulus traveling wave data from the phase-mode transform module, and performs wavelet transform on the modulus traveling wave data to obtain the wavelet Transform the modulus maximum and the polarity of the modulus maximum, and obtain the wave head polarity of the initial traveling wave of the fault according to the polarity of the modulus maximum; the fault start discrimination module receives the modulus maximum from the wavelet transform module According to the singularity detection theory of Lipschitz signal, it is determined whether the line fault causes the start-up of the protection hardware start-up module, and only when it is determined that the line fault leads to the start-up of the protection hardware start-up module, start the traveling wave fault phase selection module and polarity comparison Traveling wave direction relay module; traveling wave fault phase selection module, receiving the modulus maximum value from the wavelet transform module, and confirming the fault type and fault phase of the line according to the modulus maximum value; polarity comparison traveling wave direction relay module, Receive the wave head polarity of the fault initial traveling wave from the wavelet transform module, and confirm the fault direction of the line according to the wave head polarity of the fault initial traveling wave, and confirm whether to send the fault direction and fault phase to Information input and output module 2046.

In the above technical solution, preferably, the traveling wave data processing module 2044 may also include: a second SDRAM memory for storing the data required for processing by the traveling wave data processing module 2044; a second FLASH memory for storing the traveling wave data processing module 2044 The algorithm program adopted by the data processing module 2044 ; and the SPI communication control module, so that the traveling wave data processing module 2044 and the information input and output module 2046 perform SPI communication, and send the fault information to the information input and output module 2046 .

Fig. 3 shows a block diagram of a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection system according to an embodiment of the present invention.

As shown in Figure 3, according to the high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection system 300 of the embodiment of the present invention, the first high-voltage transmission line ultra-high-speed line as illustrated in Figure 2 is provided on the first side of the high-voltage transmission line. The wave direction longitudinal protection device 302a, the first voltage transformer 304a, the first current transformer 306a, the first circuit breaker 308a and the first Ethernet communication device 310a, and the second side of the high-voltage transmission line are provided with The illustrated second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device 302b, the second voltage transformer 304b, the second current transformer 306b, the second circuit breaker 308b and the second Ethernet communication device 310b, wherein the first The voltage transformer 304a and the second voltage transformer 304b convert the voltage on the high-voltage transmission line into the ultra-high-speed traveling wave direction longitudinal protection device 302a of the first high-voltage transmission line and the ultra-high-speed traveling wave direction of the second high-voltage transmission line respectively. The voltage of the longitudinal protection device 302b; the first current transformer 306a and the second current transformer 306b convert the current on the high-voltage transmission line into the ultra-high-speed traveling wave direction longitudinal protection device 302a and the first high-voltage transmission line respectively The current of the second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device 302b; the first high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device 302a, from the first voltage transformer 304a and the first current transformer 306a Obtain the wave head polarity of the current fault initial traveling wave on the first side of the high-voltage transmission line and the initial polarity of the power frequency component in the voltage fault traveling wave from the voltage and current respectively, and according to the current fault initial line of the first side The wave head polarity and the initial polarity of the power frequency component in the voltage fault traveling wave determine the fault direction on the first side of the high-voltage transmission line, and receive the second high-voltage transmission line ultra-high speed from the second side through the Ethernet communication device Other fault information of the longitudinal protection device in the traveling wave direction, determine the fault type and fault phase of the high-voltage transmission line according to the fault information on the first side and other fault information on the second side, and determine whether to send a trip to the first exit relay Command; the second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device obtains the current fault initial of the second side of the high-voltage transmission line from the voltage and current from the second voltage transformer 304b and the second current transformer 306b respectively The wave head polarity of the traveling wave and the initial polarity of the power frequency component in the voltage fault traveling wave, and according to the wave head polarity of the current fault initial traveling wave on the second side and the initial polarity of the power frequency component in the voltage fault traveling wave Determine the fault direction of the second side of the high-voltage transmission line, and receive other fault information from the first-side ultra-high-speed traveling wave direction longitudinal protection device of the first high-voltage transmission line through the Ethernet communication device, according to the fault information of the second side and other fault information on the first side to determine the fault type and fault phase of the high-voltage transmission line, and determine whether to send a trip command to the second exit relay; the first Ethernet communication device 310a transmits the high-voltage transmission line to the second one side of the story The fault information is transmitted to the second Ethernet communication device 310b on the second side of the high-voltage transmission line to realize the interaction of fault information at both ends of the high-voltage transmission line; the second Ethernet communication device 310b transmits the fault information on the second side of the high-voltage transmission line The fault information is transmitted to the first Ethernet communication device 310a on the first side of the high-voltage transmission line; the first circuit breaker 308a is installed on the high-voltage transmission line, and receives information from the first high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device The trip command is to open or close the high-voltage transmission line; and the second circuit breaker 308b is installed on the high-voltage transmission line to receive a trip command from the second traveling wave direction protection device to open or close the high-voltage transmission line.

Fig. 4 shows a schematic diagram of a high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection protection system according to an embodiment of the present invention.

As shown in Figure 4, the high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection system of the embodiment of the present invention can be applied to a typical 750kV transmission line, and may include: a transmission line 1, current transformers 2 and 10, Capacitive voltage transformers 3 and 11, equivalent power systems 4 and 12, busbars 5 and 13, and ultra-high-speed traveling-wave direction protection devices 6 and 14 are the ultra-high-speed traveling-wave direction longitudinal protection devices for high-voltage transmission lines shown in Figure 2 , multiplexing interface devices 7 and 15, SDH/PDH optical transmission equipment 8 and 16, SDH/PDH optical fiber communication network 9 and circuit breakers 17 and 18.

The function of each component in the high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection system shown in Figure 4 is explained as follows:

(1) Transmission line 1 is a protected transmission line.

(2) The current transformers 2 and 10 are used to transform the large current on the high-voltage transmission line into a small current such as 1 ampere.

(3) Capacitive voltage transformers 3 and 11 are used to transform the high voltage on the high voltage transmission line into a low voltage such as 57.7 volts.

(4) Equivalent power systems 4 and 12 represent power systems connected to both ends of the high-voltage transmission line.

(5) Busbars 5 and 13 represent the busbars of the substations at both ends of the high-voltage transmission line.

(6) The circuit breakers 17 and 18 are used to close and break the high voltage transmission line.

(7) SDH/PDH optical transmission devices 8 and 16 are used to convert electrical signals into optical signals and transmit them to the SDH/PDH optical fiber communication network.

(8) SDH/PDH optical fiber communication network 9, used to transmit information of each node in the SDH/PDH optical fiber network.

In this high-voltage transmission line, two ultra-high-speed traveling wave direction protection devices (such as 6 and 14) and Ethernet optical fiber communication systems (such as 7, 8 and 16, 15, 9) arranged at both ends of the protected transmission line 1 constitute An important part of the ultra-high-speed traveling-wave direction longitudinal protection system for high-voltage transmission lines is developed, in which the ultra-high-speed traveling-wave direction protection device is used to realize relay protection; and the Ethernet optical fiber communication system is used to exchange fault information of the two protection devices. The structure and detailed functions of the two important parts are described as follows:

1. The ultra-high-speed traveling-wave direction protection device applied in the ultra-high-speed traveling-wave direction longitudinal protection system of this high-voltage transmission line can have a composition structure as shown in Figure 5, which can include a power board 21, a precision current converter and Precision voltage converter board 22, ultra-high-speed traveling wave protection board 23, monitoring board 24, outlet relay board 25, these device boards are connected on the motherboard 20 side by side and fixed in the cabinet 19, on the front panel of the outer surface of the cabinet There are also a liquid crystal display 191 and operation buttons 192 .

The models and functions of each device in the ultra-high-speed traveling wave direction protection device are described as follows:

(1) Chassis 19: install and fix various functional boards, and have the function of shielding external electromagnetic interference.

Liquid crystal display screen 191: used to display line information during normal operation and fault information such as fault reports and fault recordings after faults. The LCD screen adopts a color 3.5-inch TFT LCD screen with a resolution of 320×240.

Operation button 192: used to set the protection value, display fault information such as fault report and fault recording, and realize related operations of human-computer interaction. The operation keys adopt a 3×4 matrix keyboard to realize the user’s operation of the ultra-high-speed traveling wave direction protection device.

(2) Motherboard 20 : for transmitting interaction signals between function boards.

(3) Power supply board 21: provide direct current power to each function board, can provide digital power supply 5 volts and digital ground, analog power supply plus or minus 5 volts, plus or minus 12 volts, plus or minus 24 volts and analog ground. The power supply is 500 watts.

(4) Precision current converter and precision voltage converter board 22: consists of 4 precision current converters modeled as UCT-01-5A/3.53mA and 4 precision voltage converters modeled as TV3154-100V/3.53V. The function of this function board is to transform the 57.7 volt voltage on the secondary side of the capacitive voltage transformer and the 1 ampere current on the secondary side of the current transformer into positive and negative 2.5 volt weak current signals for use by the ultra-high-speed traveling wave protection board.

(5) Ultra-high-speed traveling wave protection board 23: the function of this function board is to collect the current traveling wave signal and voltage traveling wave signal after the fault, and perform phase-mode conversion and Multi-resolution decomposition algorithm of wavelet transform, software discrimination of fault startup, phase selection of traveling wave fault and processing of protection relay algorithm for polarized current fault traveling wave direction. At the same time, send the fault direction information of the own side of the high-voltage transmission line to the ultra-high-speed traveling wave direction protection device on the opposite side of the high-voltage transmission line, receive the fault direction information of the ultra-high-speed traveling wave direction protection device on the opposite side, and receive local binary input information, and carry out the logical judgment of the direction protection of the traveling wave longitudinal connection, and send out output information according to the judgment result.

The hardware structure of the ultra-high-speed traveling wave protection board can be shown in Figure 6, which consists of a high-speed data acquisition circuit 602, a high-speed digital signal processing circuit 604, and a protection logic judgment and input-output interface circuit 606.

The composition and functions of the three parts are described as follows:

1. High-speed data acquisition circuit 602:

The high-speed data acquisition circuit 602 may include a second-order active low-pass filter module 6022, a second-order passive band-pass filter module 6024, a protection hardware startup module 6026, a multiplex switch module 6028, an A/D conversion module 60210, and a dual-port RAM Module 60212, complex programmable device (CPLD) EMP7128S control and decoding module 60214. in:

1) Second-order active low-pass filter module 6022:

After the 8-channel analog signal is input to the ultra-high-speed traveling wave protection board 23 through the motherboard terminals, it enters the second-order active low-pass filter module 6022. The cut-off frequency of the second-order active low-pass filter module 6022 is 250 kHz, which satisfies Shannon's sampling theorem and filter out high frequency interference.

2) Second-order passive bandpass filter module 6024:

The second-order passive band-pass filter module 6024 has a band-pass frequency of 3 kHz to 30 kHz, and extracts the high-frequency signal in the traveling wave of the current fault as the start signal of the traveling wave protection hardware.

3) The protection hardware startup module 6026 can be a level comparison circuit as shown in the figure:

The module constitutes a level comparison circuit through an operational amplifier. When the level of the high-frequency part (3kHz~30kHz) in the current fault traveling wave after passing through the band-pass filter exceeds the preset hardware start-up level, the hardware start-up circuit sends a start The signal is sent to the complex programmable logic device EMP7128S60214, and the complex programmable logic device EMP7128S60214 triggers the interrupt of the high-speed digital signal processor TMS320C6713 and enters the fault handling program.

4) Multiplexer switch module 6028:

The multi-channel switch MAX46396028 is a four-way high-speed switch, which outputs four analog signals to the A/D conversion module 60210 in turn. Two pieces of MAX4639 can realize the conversion of 8 analog signals.

5) A/D conversion module 60210:

The A/D conversion module 60210 uses two AD9240 high-speed analog/digital conversion switches 60210a and 60210b to realize high-speed analog/digital conversion of analog signals, and the data sampling rate of each analog signal reaches 1MHz.

6) Dual-port RAM module 60212:

2 pieces of dual-port RAM60212 are used to store the 8 digital signals converted by the A/D conversion module 60210, and the storage space is 128Kbyte.

7) Complex programmable logic device EMP7128S control and decoding module 60214:

The complex programmable logic device EMP7128S60214 is the core control part of the high-speed data acquisition circuit 602, which realizes the coordinated control of the multiplex switch module 6028, the A/D conversion module 60210 and the dual-port RAM module 60212 and the decoding of address/data signals , to convert 8 channels of analog signals into digital signals and store them in the dual-port RAM module 60212. At the same time, the complex programmable logic device EMP7128S60214 triggers the high-speed digital signal processor TMS320C6713 to enter the fault handling program after the traveling wave protection hardware is started.

2. High-speed digital signal processing circuit 604

The high-speed digital signal processing circuit 604 takes DSP TMS320C67136042 as the core, including: high-speed digital signal processor (DSP) TMS320C67136042, SPI communication module 6044, SDRAM memory 6046, FLASH memory 6048, phase-to-mode transformation algorithm module and wavelet transformation algorithm integrated in TMS320C67136042 module, a fault starting software discrimination algorithm module, a traveling wave fault phase selection algorithm module, and a polarizing current fault traveling wave direction relay.

The functions of each part in the high-speed digital signal processing circuit 604 are as follows:

1) TMS320C67136042:

This is a high-speed digital signal processing chip with a 32-bit data bus, which can perform floating-point calculations with high precision. There are 8 computing units inside the chip, which can execute 1.6 billion instructions per second, which can meet the needs of ultra-high-speed traveling wave protection at the same time. To meet the requirements of data processing speed and precision, the core algorithm program of ultra-high-speed traveling wave protection is integrated in TMS320C6713.

2) SPI communication control 6044:

TMS320C67136042 communicates with processor MCF52826062 through SPI serial communication, and transmits fault information data such as fault direction and fault recording to MCF52826062, so that MCF5282 can perform subsequent protection logic judgment and communication operations. The SPI communication rate reaches 5Mbtye/s.

3) SDRAM memory 6046:

Two pieces of SDRAM memory with the model of HY57V641620 are used to form a 32-bit 2Mbyte random access memory, which is used to store the data required by the algorithm and the fault recording data.

4) FLASH memory 6048:

The FLASH program memory SST39LF of 512K bytes is used to store the algorithm program. After the TMS320C67136042 is powered on, the program in the FLASH memory 6048 is automatically read into the internal RAM of the TMS320C67136042 to run.

The algorithm program flow chart in TMS320C67136042 is shown in Figure 7. The program is solidified in the FLASH memory. After power-on, TMS320C6713 automatically reads the program in the FLASH into the internal RAM of TMS320C6713 to run. The main functions completed by the program are:

As shown in the flow chart on the left side of Fig. 7, it is the self-inspection when the high-speed digital signal processing chip runs normally, at first carry out initialization (702), judge whether there is fixed value modification (704), under the situation that judged result is yes, Carry out step (706), under the situation that judgment result is negative, carry out step (708), judge whether to have report (708) after revising fixed value (706), when judgment result is yes, send this report (710), After sending, judge whether the self-inspection time has arrived (712), if not yet, then re-judge whether there is fixed value modification, if arrived, then carry out self-inspection (714);

Continue as shown in the flow process on the right side of Figure 7, TMS320C6713 detects whether there is a fault interruption in real time, and when there is a fault interruption, read the fault data (716);

Carry out phase-mode transformation (718) to the fault data read;

Calculating multi-resolution decomposition of wavelet transform and its modulus maximum (720);

Determine whether the fault is started (722), if not started, then the fault interruption process ends, if started, then carry out the fault direction judgment of the fault phase selection and polarizing current fault direction relay (724);

Judging whether the fault direction is a forward fault (726), when the judgment result is a forward fault, then the fault information is sent to the MCF5282 (728), and the fault processing interruption ends, and when the judgment result is not a forward fault, the fault processing interruption ends.

According to the process shown in Figure 7, the functions of each software module are as follows:

1) TMS320C6713 starts: After the traveling wave direction protection device is powered on, TMS320C6713 starts.

2) Initialization module: initialize the internal registers of TMS320C6713, initialize the relevant variables and flag bits in the protection algorithm, and open the DSP interrupt.

3) Self-inspection module: perform self-inspection on the SDRAM memory and SPI communication module on the periphery of TMS320C6713.

4) Interrupt start: The interrupt controller in the TMS320C6713 chip will monitor in real time whether there is a fault interrupt, and if there is a fault interrupt, it will immediately go to the fault interrupt processing program.

5) Read fault data: TMS320C6713 reads current traveling wave and voltage traveling wave data from dual-port RAM to prepare for fault handling.

6) Phase-mode transformation: The three-phase current traveling wave and voltage traveling wave data are respectively subjected to Karen Bell transformation, and transformed into three line-mode components and one zero-mode component.

$\left[\begin{array}{c}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}\\ {\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}\\ {\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}\\ {\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}\end{array}\right]<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}\left[\begin{array}{ccc}\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}\\ \mathrm{<span\; class="notranslate">\; 1</span>}& <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 0</span>}\\ <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 0</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}\\ \mathrm{<span\; class="notranslate">\; 0</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}& <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}\end{array}\right]\left[\begin{array}{c}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}\\ {\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}}\\ {\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; c</span>}}\end{array}\right]<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

$\left[\begin{array}{c}{\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}\\ {\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}\\ {\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}\\ {\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}\end{array}\right]<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}\left[\begin{array}{ccc}\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}\\ \mathrm{<span\; class="notranslate">\; 1</span>}& <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 0</span>}\\ <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; 0</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}\\ \mathrm{<span\; class="notranslate">\; 0</span>}& \mathrm{<span\; class="notranslate">\; 1</span>}& <span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}\end{array}\right]\left[\begin{array}{c}{\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}\\ {\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}}\\ {\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; c</span>}}\end{array}\right]<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

7) Calculate the multi-resolution decomposition of wavelet transform and its modulus maximum:

The schematic diagram of multi-resolution decomposition of wavelet transform is shown in Fig. 8. The decomposition formula of binary discrete wavelet transform is as formula (3):

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; V</span>}}_{{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; j</span>}}}\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; V</span>}}_{{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}}\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span>\\ {\mathrm{<span\; class="notranslate">\; W</span>}}_{{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; j</span>}}}\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; V</span>}}_{{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}}\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span>\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

In the above formula, f(n) is the discrete sampling value point of the current traveling wave or voltage traveling wave, h _k and g _k are the filter bank coefficients in the binary discrete wavelet transform decomposition algorithm,

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 0.125,0.375,0.375,0.125</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1,0,1,2</span>}<span\; class="notranslate">\; )</span>\\ {\mathrm{<span\; class="notranslate">\; g</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2,2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0,1</span>}<span\; class="notranslate">\; )</span>\end{array}\right\}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

Perform wavelet transform multi-resolution decomposition on the current traveling wave signal to obtain the modulus maxima and the polarity of the modulus maxima in the sub-frequency spaces W2, W3, W4, so as to obtain the wave head polarity SI of the initial traveling wave of the current fault _α , SI _β , SI _γ .

For the voltage traveling wave modulus, first extract the fault traveling wave component in the voltage traveling wave according to the formula (5):

u _fm (n)＝u _m (n)-2u _m (nN)+u _m (n-2N) (5)

In the above formula, u _m (n) is the value of the voltage traveling wave modulus after the fault of the high-voltage transmission line. .

Decompose the voltage fault traveling wave u _fm (n) with multi-resolution wavelet transform, and obtain the polarity of the modulus maximum value in the frequency space V12 (0-61.0Hz), so as to obtain the power frequency component in the voltage fault traveling wave initial polarity.

8) Software discrimination of fault startup: According to the singularity detection theory of the lipschitz signal, if the transmission line fault starts, the modulus maxima of the wavelet transform modulus maxima of the current traveling wave in the spaces W2, W3 and W4 will increase sequentially , and carry out corresponding follow-up fault handling procedures. If the high-frequency interference signal causes the traveling wave protection hardware to start, the modulus maxima of the wavelet transform in the W2, W3 and W4 spaces do not increase sequentially. At this time, immediately exit the fault handling interrupt program and return to TMS320C6713 main loop program.

9) Traveling wave fault phase selection module: The fault phase selection module is constructed according to the wavelet transform modulus maximum value of the current traveling wave. The flow of the fault phase selection algorithm is shown in Figure 9, and the basic work flow is:

First determine the fault type:

In step 902, it is judged whether the zero-mode component of the current traveling wave is zero;

If the zero-mode component of the current traveling wave after the fault is not 0, it is judged as a ground fault, otherwise it is a phase-to-phase short circuit.

In step 906, if it is a ground fault, then determine whether there is a wavelet transform modulus maximum value of 0 among the three current line-mode wavelet transform modulus maxima, and if there is a wavelet transform modulus maxima value of 0, then it is single-phase Ground short circuit, otherwise it is a two-phase ground short circuit.

Not at 904, but for phase-to-phase short circuit, the absolute maximum value MMImax and the absolute minimum value MMImin among the three current line-mode wavelet transform modulus maxima are further obtained.

In step 908, it is judged whether MMImax is equal to 2MMImin, if MMImax=2MMImin, then it is judged as two-phase short circuit, otherwise it is three-phase short circuit.

According to the fault type, further determine the fault phase:

Phase-to-phase judgment of two-phase short-circuit faults:

If MMIα＝MMIγ, the fault phase difference: CA

If MMIβ=MMIγ, the fault phase difference: AB

If MMIα＝MMIβ, the fault phase difference: BC

Phase identification of three-phase short-circuit fault: then fault phase identification: ABC

Judgment of single-phase ground short circuit phase:

If MMIγ＝0, the fault phase difference: A

If MMIβ=0, the fault phase is different: B

If MMIα=0, then the fault phase is different: C

Phase-to-ground short-circuit fault judgment:

In step 910, inverse Karen Bell transform is performed to obtain MMIa, MMIb, MMIc from MMIα, MMIβ, MMIγ;

In step 912, find the minimum absolute value among MMIa, MMIb, and MMIc:

MMImin=min(abs(MMIa), abs(MMIb), abs(MMIc))

If MMImin=abs(MMIa), the faults are different: BC

If MMImin=abs(MMIb), the faults are different: CA

If MMImin=abs(MMIc), then the faults are different: AB

10) Polarization current fault traveling wave direction relay:

According to the modulus maxima MMIα, MMIβ, MMIγ of current traveling wave wavelet transform multi-resolution decomposition in W2 space and voltage fault wavelet transform multi-resolution decomposition of wavelet transform multi-resolution decomposition of modulus maxima MMUα, MMUβ, MMUγ in V12 space to determine the fault direction. The forward criterion and reverse criterion of the polarizing current fault traveling wave direction relay are shown in Fig. 10a and Fig. 10b:

As shown in Fig. 10a, positive direction fault: any line modulus voltage fault traveling wave modulus maximum value and current fault traveling wave modulus maximum value are opposite in polarity.

As shown in Figure 10b, reverse direction fault: the maximum values of the three line modulus voltage fault traveling wave moduli and the current fault traveling wave modulus have the same polarity.

11) SPI serial communication module

When the polarizing current fault travel wave direction relay is judged to be a forward fault, TMS320C6713 communicates with the processor MCF5282 through SPI serial communication, and transmits data such as fault direction and fault recording to MCF5282, so that MCF5282 can carry out subsequent protection logic judgment and communications etc.

3. Protection logic judgment and input/output interface circuit 606

Protection logic judgment and input/output interface circuit 606 takes microprocessor MCF52826062 as the core, including: microprocessor MCF5282 module 6062, SPI communication module 6044, Ethernet control module 6066, switch value input module 6068, switch value output module 6068, CAN Communication module 60610, 232 communication module 6064, integrated in MCF5282 inside the traveling wave direction longitudinal protection logic judgment algorithm. As shown in Figure 6, the functions of each functional module are as follows:

1) Microprocessor MCF5282 module 6062: MCF5282 is a 32-bit high-performance industrial control chip produced by Freescale, which integrates a wealth of commonly used peripheral function modules, such as integrating 3 timers , 2 SPI communication ports, 1 CAN communication controller, 1 Ethernet controller, a large number of general-purpose input and output interfaces (GPIO), etc. At the same time, the chip integrates 256Kbyte FALSH and 64Kbyte SRAM, and the operation performance is stable and reliable.

2) SPI communication module 6044: MCF5282 communicates with TMS320C6713 through SPI to obtain results such as fault direction, fault phase difference, and fault recording.

3) Ethernet control module 6066: transmit the fault information such as the fault direction and fault phase difference on the own side of the line to the longitudinal protection device in the traveling wave direction on the opposite side of the transmission line through Ethernet communication; at the same time receive the longitudinal protection device in the traveling wave direction on the opposite side The device transmits the fault information to the longitudinal protection device in the traveling wave direction of the local side through Ethernet.

4) Switching value input module 6068: transmits the relevant switching value information for the traveling wave direction protection device on this side to the microprocessor MCF5282 for subsequent protection logic judgment.

5) Switching value output module 60612: According to the judgment result of the longitudinal protection in the traveling wave direction, a switch trip command and related alarm information are issued when there is a fault in the area.

6) CAN communication module 60610: transmit the fault report information related to the fault handling of the longitudinal protection in the traveling wave direction to the monitoring board, so as to realize the storage and display of the fault report.

7) 232 communication module 6064: Realize online debugging of ultra-high-speed traveling wave direction protection board.

8) The logical judging algorithm flow of longitudinal protection in the traveling wave direction in MCF5282 is shown in Figure 11. The flow chart on the left is the self-inspection of MCF5282 during normal operation, and the flow of judgment is on the right. The vertical direction protection constitutes the protection trip logic according to the permission signal. The MCF5282 receives the local fault information transmitted by the DSP through the SPI communication interruption, reads the fault information (1102), and transmits the fault information to the The contralateral traveling wave direction protection device (1104), simultaneously detects whether the Ethernet controller receives the fault information of the contralateral traveling wave direction protection device (1106), and judges whether the waiting delay reaches the set value (1108), if it is within the specified delay time If no fault information is received from the protection device in the traveling wave direction on the opposite side, it is judged to be an external fault of the protected line; The traveling wave direction protection device on the local side will combine the binary input information on the local side to determine whether it is tripped or not (1110), and finally send a fault report and fault recording to the monitoring board.

(6) Monitoring board 24

The main function of the monitoring board is to monitor and manage the traveling wave protection device, which may include: microprocessor MCF5282, serial port module, CAN communication module, Ethernet communication module, clock module, FLASH memory module, SDRAM memory module, integrated in MCF5282 Embedded operating system, liquid crystal display module, keyboard operation module, inspection module, upload fault report and fault recording module, download fixed value module, equipment debugging module.

The structure of the hardware of this monitoring board 24 is as shown in Figure 12, and each module function is as follows:

1) Microprocessor MCF52821202: The microprocessor used in the monitoring board is a 32-bit embedded microprocessor chip MCF5282 produced by Freescale. This processor is the core calculation and control component of the monitoring board. All functions of the board are It is completed by the chip and the program modules integrated in it.

2) FLASH memory 1218: the memory module adopts AMD AM29LV160DB-90EI, which is 16-bit 2M byte FLASH. It is mainly used to store the MCF5282 embedded operating system kernel, application programs, wave recording data and fault reports, etc.

3) SDRAM memory 1216: The monitoring board uses two 16-bit 8M-byte SDRAMs to form a 32-bit 16M-byte memory space. The SDRAM model is MT48LC4M16A2-75, which is used to store the intermediate data of MCF5282 program operation.

4) Clock module 1210: PCF8563 clock chip is used for timing and provides unified clock information to the protection device, which can be accurate to the second level.

5) Serial port module 1204: The monitoring board uses two RS232 serial port level conversion chips MAX3232EEPE, one for controlling the display of the LCD screen, and one for outputting and inputting debugging information.

6) Ethernet module 1208: The monitoring board completes the remote transmission of data through the Ethernet module 1208. The Ethernet physical layer chip is LXT971ALC, the Ethernet isolation transformer is HR601680, and the Ethernet physical interface is RJ45.

7) CAN communication module 1206: The monitoring board completes the information interaction with the high-speed data acquisition and ultra-high-speed traveling wave protection board through the CAN communication module 1206, and the CAN communication chip adopts CTM8251AT.

8) Embedded module 1300 integrated in MCF5282: the structural diagram of the embedded module is shown in FIG. 13 .

The monitoring board adopts embedded uClinux operating system to complete the control of hardware equipment and realize various functions, including: liquid crystal display, keyboard control, patrol inspection, equipment debugging, downloading fixed value, uploading fault report and fault recording, various functions The specific functions of the module are as follows:

Liquid crystal display module 1302: real-time display of line current and voltage values, fault reports, fault recording waveforms, and protection settings.

Keyboard operation module 1304: change the protection setting, view the fault report and fault recording waveform, and perform machine debugging.

Inspection module 1306: After the protection device is powered on for 1 minute, the monitoring board 24 inspects the high-speed data acquisition and ultra-high-speed traveling wave protection board once every 10 seconds through CAN communication. If the inspection is abnormal, an alarm message will be issued.

Upload fault report and fault recording module 1312: Receive high-speed data acquisition and fault report and fault recording data from the ultra-high-speed traveling wave protection board 23 through CAN communication, and store them in the FLASH memory.

Downlink fixed value module 1310: reset the protection fixed value by the user, and send it to the high-speed data acquisition and ultra-high-speed traveling wave protection board through CAN communication.

Equipment debugging module 1308: the user can debug the traveling wave protection device through human-computer interaction interfaces such as keyboards and liquid crystals.

(7) Export relay board 25

There are three-phase export tripping relays, closing relays, alarm relays, etc. in the exit relay board. Realize the tripping exit, closing operation, alarm and other functions of the ultra-high-speed traveling wave direction protection device.

2. Ethernet communication system

The Ethernet communication system may include: Ethernet optical port of traveling wave protection device; multiplexing interface device; SDH/PDH optical transmission equipment and SDH/PDH optical fiber communication network, as shown in Figure 14b, the functions of each part are as follows:

Ethernet optical port of traveling wave protection device: The ultra-high-speed traveling wave direction protection device adopts single-mode HFBR5203 optical port, which converts the fault information electrical signal of the traveling wave protection on this side into an optical signal, and sends it to the ultra-high-speed The traveling wave direction protection device converts the optical signal transmitted by the opposite side traveling wave protection through the optical fiber network into an electrical signal.

Multiplexing conversion devices C1 and C2: realize the conversion between the optical port and the standard electrical interface G703E1, so that the signal enters the SDH/PDH optical transmission equipment for transmission.

SDH/PDH optical transmission equipment D1 and D2: Convert the electrical signal converted by the multiplexing conversion device into an optical signal through the optical transceiver, and transmit it to the opposite side SDH/PDH optical transmission equipment through the SDH/PDH optical fiber communication network.

The Ethernet optical fiber communication system for longitudinal protection in the traveling wave direction can use dedicated optical fiber communication, as shown in Figure 14a, or multiplex (2M) SDH/PDH optical fiber communication network communication, as shown in Figure 14b.

In other words, in the case of using dedicated optical fiber communication, the Ethernet communication device includes: the Ethernet optical port of the traveling wave protection device, which is used to convert the fault information electrical signal of the traveling wave protection device at the local end into a fault information optical signal. The communication network sends to the traveling wave protection device at the other end of the high-voltage transmission line, and at the same time receives other fault information optical signals transmitted through the dedicated optical fiber communication network at the other end and converts other fault information optical signals into other fault information electrical signals;

In the case of using SDH/PDH optical fiber communication, the Ethernet communication device includes: traveling wave protection device Ethernet optical port, multiplexing interface device, SDH/PDH optical transmission equipment, among which,

The multiplexing interface device is connected to the Ethernet optical port of the traveling wave protection device, receives the fault information optical signal sent by the Ethernet optical port of the traveling wave protection device, and converts the fault information optical signal into a fault information electrical signal;

SDH/PDH optical transmission equipment, connected to the multiplexing interface device, converts the information electrical signal converted by the multiplexing interface device into an information optical signal, and transmits it to the SDH/PDH optical transmission at the other end through the SDH/PDH optical fiber communication network equipment.

After describing in detail the composition, structure and function of each component of the present invention, the technical solution of the present invention will be further described in conjunction with the following examples.

The working process of the technical solution of the present invention is illustrated in conjunction with the accompanying drawings:

1) Assume that a fault occurs inside the protected line 1, as shown in Figure 4;

2) The fault point will generate current fault traveling waves and voltage fault traveling waves moving to both sides of the line.

3) The current transformers 2 and 10 on both sides of the line transform the primary side current traveling wave to the secondary side; the capacitive voltage transformers 3 and 11 transform the primary side voltage traveling wave to the secondary side.

4) In the ultra-high-speed traveling wave direction protection devices 6 and 14, the precision current converter and the precision voltage converter on the precision current converter and precision voltage converter board 22 further convert the current traveling wave and the voltage traveling wave into positive and negative 2.5 Volts of weak electrical signals. The signal is transmitted to the ultra-high speed traveling wave protection board 23 via the motherboard 20 .

5) In the ultra-high-speed traveling wave protection board 23, after the voltage traveling wave and current traveling wave signals pass through the second-order active low-pass filter circuit, after being converted by a multi-channel switch and A/D high-speed (500kHz) digital conversion, they become The digital signal is stored in the dual-port RAM; at the same time, the output signal of the second-order active low-pass filter circuit is transmitted to the traveling wave protection hardware start-up circuit through the second-order band-pass filter to generate a fault start signal, and start the TMS320C6713 to enter the fault handling program.

6) After TMS320C6713 enters the fault processing program, it first reads the fault data from the dual-port RAM, performs phase-mode transformation on the voltage traveling wave and current traveling wave fault data, and then performs multi-resolution decomposition of wavelet transform to obtain the current traveling wave Modulus maxima in frequency space W2{62.5, 125kHz}, W3{31.25, 62.5kHz}, W4{15.625, 31.25kHz}. According to the singularity detection theory of the Lipschitz signal, the software judgment of the fault start is carried out. If the traveling wave protection is started due to the interference signal, the traveling wave direction protection will immediately exit the fault processing procedure; if the traveling wave protection is started due to the line fault, the protection device will Enter the algorithm program of traveling wave fault phase selection and polarizing current fault traveling wave direction relay. If it is a reverse fault, the traveling wave direction protection immediately exits the fault handling procedure; if it is a forward fault, TMS320C6713 starts the SPI communication with MCF5282, and transmits the relevant fault information to MCF5282 for subsequent fault handling procedures.

7) MCF5282 transmits the fault information transmitted by TMS320C6713 immediately through the Ethernet optical fiber communication network, and transmits the fault information to the ultra-high-speed traveling-wave direction protection device on the opposite side, and at the same time detects whether it receives the ultra-high-speed traveling-wave direction protection device on the opposite side through the Ethernet If the fault information transmitted by the network does not receive the fault information from the ultra-high-speed traveling wave direction protection device on the opposite side within the set waiting delay, it will be judged as an out-of-area fault; if within the set waiting delay After receiving the fault information from the ultra-high-speed traveling wave direction protection device on the opposite side, the traveling wave direction protection combines the binary input information of this side to make a logical judgment to determine whether to trip and the difference between trips. The tripping signal is outputted by the microprocessor MCF5282 to drive the tripping relay on the outlet relay board 25 to send a tripping command. Finally, the MCF5282 transmits the fault report and fault recording information to the monitoring board 24 through CAN communication.

8) The monitoring board 24 receives the fault report and fault recording transmitted by the ultra-high-speed traveling wave protection board through CAN communication. On the one hand, it displays the fault information on the LCD screen, and at the same time transmits the fault report and fault recording data through Ethernet To substation monitoring system and dispatch center monitoring system.

The technical scheme of the present invention overcomes the deficiencies of the existing protection technology, uses high-speed data acquisition technology, high-speed digital signal processing technology, and multi-resolution decomposition technology using wavelet transform to extract the wave head polarity of the initial traveling wave of the high-voltage transmission line current fault and the initial polarity of the power frequency fault component in the voltage fault traveling wave form a directional relay based on the polarization current fault traveling wave, and use the Ethernet optical fiber communication technology to form a directional longitudinal protection system. The ultra-high-speed traveling wave direction longitudinal protection system for high-voltage transmission lines has ultra-high-speed action performance (the fastest action speed is about 10ms), and is not affected by the saturation of current transformers, and is not affected by capacitive voltage transformers. It is not affected by the voltage fault traveling wave signal, not affected by the power system oscillation, not affected by the charging capacitor current of the transmission line, not affected by the series capacitor and shunt reactor of the transmission line, not affected by the transition resistance, and can be used as a high voltage Primary protection of transmission lines. The following performance indicators can be achieved:

1. The data sampling rate of the ultra-high-speed traveling wave direction protection device is optional from 0 to 1MHz;

2. The exit time of the polarizing current fault traveling wave direction relay is less than 5ms;

3. The Ethernet communication time in the ultra-high-speed traveling wave direction longitudinal protection system is less than 5ms;

4. The action exit time of the whole set of protection is less than 15ms;

5. Able to record 30 groups of protection action fault reports and fault recording data.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (4)

1. A high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device is characterized in that it is installed on one side of the high-voltage transmission line, including: a converter, a traveling wave protector, a monitor and an outlet relay, wherein, The converter, connected to the traveling wave protector, converts the first voltage and current from the high-voltage transmission line into a second voltage and current for use by the traveling wave protector; The traveling wave protector is connected to the monitor, receives the second voltage and current from the converter, processes the second voltage and current to determine the fault information of the high-voltage transmission line, and converts the transmit the fault information to the monitor, send the fault information and receive other fault information from the outside, and compare the fault information determined by the traveling wave protector with the other fault information from the outside , and determine whether to trip and the phase difference according to the comparison result, and the fault information includes the fault direction and the fault phase; The monitor, connected to the traveling wave protector, displays and stores the fault information transmitted by the traveling wave protector, monitors the traveling wave protector according to input preset information, and stores the fault information sent externally; and The exit relay receives the judgment result of the traveling wave protector, and determines whether to issue a trip command according to the judgment result; The monitors include: A microprocessor, connected to the first CAN communication module, receives fault information from the traveling wave protector and input information from the keyboard module, transmits the input information of the keyboard module to the traveling wave protector, and controls the liquid crystal Display the display content of the module; The first CAN communication module is connected to the microprocessor to realize information interaction with the traveling wave protector; An Ethernet communication module, receiving the fault information from the traveling wave protector, and transmitting the fault information to the outside; A serial port module, connected to the microprocessor, transmits the display content and debugging signals; A liquid crystal display module, connected to the microprocessor, displays the display content from the microprocessor and the information input through the keyboard module; The keyboard module inputs external information; The first FLASH memory is used to store the control program of the microprocessor and the fault information; and The first SDAM memory is used to store the intermediate data processed by the microprocessor; in, The microprocessor also includes: An inspection module, connected to the first CAN communication module, regularly inspects the traveling wave protector through the first CAN communication module, and sends an alarm message when the inspection finds an abnormal state; An upload module, connected to the first CAN communication module, receives the fault information from the traveling wave protector through the first CAN communication module, and stores it in the FLASH memory; The download module is connected to the first CAN communication module, and transmits the protection setting reset by the user to the traveling wave protector through the first CAN communication module; The traveling wave protector includes: a traveling wave data acquisition module, a traveling wave data processing module and an information input and output module, wherein, The traveling wave data acquisition module includes: a core control module, a second-order active low-pass filter module, a second-order passive band-pass filter module, a protection hardware startup module, a multiplexer switch module, an A/D conversion module, a dual port RAM module, where The second-order active low-pass filter module receives a traveling wave analog signal from the high-voltage transmission line, and filters the traveling wave analog signal, and the traveling wave analog signal includes a voltage traveling wave analog signal and a current traveling wave analog signal; The second-order passive band-pass filter module is connected to the second-order active low-pass filter module, and is used to extract the high-frequency signal in the traveling wave from the output signal of the second-order active low-pass filter module ; The protection hardware startup module receives the high-frequency signal from the second-order passive bandpass filter module, and determines whether the high-frequency signal satisfies a predetermined condition, after the high-frequency signal satisfies the predetermined condition , sending a start signal to the core control module; The multiplexing switch module is connected to the second-order active low-pass filter module, and is used to sequentially output the traveling wave analog signal to the A/D converter after receiving the control signal from the core control module module; The A/D conversion module is connected to the multi-channel conversion switch module, performs A/D conversion on the traveling wave analog signal according to the control signal from the core control module, and outputs the conversion result to the dual-port RAM module; The dual-port RAM module has two sets of data buses and two sets of address buses, which are used to store the conversion results from the A/D conversion module under the control of the core control module, and are used by the traveling wave The data processing module reads the conversion result; and The core control module receives the startup signal from the protection hardware startup module, controls the multiplexer, the A/D converter, and the dual-port RAM, and implements the address bus Decoding with the data bus, and sending an interrupt signal to the traveling wave data processing module; The traveling wave data processing module receives an interrupt signal from the core control module, reads the conversion result from the dual-port RAM, and processes the conversion result to obtain fault information, wherein the fault information Including the fault direction and fault phase of the high-voltage transmission line; Information input and output modules, including: information processing module, Ethernet control module, switch input module, switch output module, wherein, The information processing module receives fault information from the traveling wave data processing module, receives other fault information from the other side of the high-voltage transmission line through the Ethernet control module, and receives fault information from the switch input The switching value information of the module, according to the fault information from the traveling wave data processing module, other fault information from the other side and the switching value information, determine whether to trip or not; The Ethernet control module sends the fault information from the information processing module to the traveling wave direction protection device on the other side of the high-voltage transmission line, and receives the traveling wave direction protection device from the other side The other fault information sent by the device, sending the other fault information to the information processing module; The switching value input module inputs the switching value information used by the traveling wave protection device to the information processing module; and The switch value output module receives the tripping command and the trip phase difference from the information processing module and sends it to the outlet relay; The second CAN communication module receives the fault report information from the information processing module and sends it to the monitor; and The RS232 communication module receives a debugging signal from the monitor for debugging the traveling wave protector. 2. The ultra-high-speed traveling wave direction longitudinal protection device for high-voltage transmission lines according to claim 1, wherein the traveling wave data processing module includes: a phase-mode transformation module, a wavelet transformation module, a fault start discrimination module, a traveling wave Fault phase selection module, polarity comparison traveling wave direction relay module, in which The phase-mode transformation module performs Karen Bell transformation on the conversion result from the dual-port RAM to obtain modulus traveling wave data; The wavelet transform module receives the modulus traveling wave data from the phase-to-mode transform module, and performs wavelet transform on the modulus traveling wave data to obtain the modulus maximum value of the wavelet transform and the modulus maximum value polarity, and obtain the wave head polarity of the fault initial traveling wave according to the polarity of the modulus maximum; The fault start discrimination module receives the modulus maximum value from the wavelet transform module, determines whether it is a line fault that causes the start of the protection hardware start module according to the singularity detection theory of the Lipschitz signal, and only when When it is determined that the line fault causes the start of the protection hardware start module, start the traveling wave fault phase selection module and the traveling wave direction relay module when comparing the polarity; The traveling wave fault phase selection module receives the modulus maximum value from the wavelet transform module, and confirms the fault type and fault phase of the line according to the modulus maximum value; The polarity comparison type traveling wave direction relay module receives the wave head polarity of the fault initial traveling wave from the wavelet transform module, and confirms the fault direction of the line according to the wave head polarity of the fault initial traveling wave , and confirm whether to send the fault direction and the fault phase to the information input and output module according to the fault direction on the line. 3. The ultra-high-speed traveling wave direction longitudinal protection device for high-voltage transmission lines according to claim 2, wherein the traveling wave data processing module further comprises: The second SDRAM memory is used to store the data required for processing by the traveling wave data processing module; The second FLASH memory is used to store the algorithm program adopted by the traveling wave data processing module; and The SPI communication control module enables the traveling wave data processing module to perform SPI communication with the information input and output module, and sends the fault information to the information input and output module. 4. A high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection system, characterized in that the first side of the high-voltage transmission line is provided with a high-voltage transmission line ultra-high-speed traveling wave as described in any one of claims 1 to 3. The first high-voltage transmission line ultra-high-speed traveling wave directional longitudinal protection device of the directional longitudinal protection device, the first voltage transformer, the first current transformer, the first circuit breaker and the first Ethernet communication device, and the high-voltage The second side of the transmission line is provided with the second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device as described in any one of claims 1 to 3, the second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device, the second A voltage transformer, a second current transformer, a second circuit breaker and a second Ethernet communication device, wherein, The first voltage transformer and the second voltage transformer convert the voltage on the high-voltage transmission line into voltages respectively provided to the ultra-high-speed traveling wave direction longitudinal protection device for the first high-voltage transmission line and the first voltage transformer. 2. The voltage of the longitudinal protection device in the ultra-high-speed traveling wave direction of the high-voltage transmission line; The first current transformer and the second current transformer convert the current on the high-voltage transmission line to provide to the ultra-high-speed traveling wave direction longitudinal protection device of the first high-voltage transmission line and the first high-voltage transmission line respectively. 2. The current of the longitudinal protection device in the ultra-high-speed traveling wave direction of the high-voltage transmission line; The ultra-high-speed traveling wave direction longitudinal protection device for the first high-voltage transmission line obtains the first side of the high-voltage transmission line from the voltage and current from the first voltage transformer and the first current transformer, respectively. The polarity of the wave head of the initial traveling wave of the current fault and the initial polarity of the power frequency component in the voltage fault traveling wave, and according to the wave head polarity of the initial traveling wave of the current fault on the first side and the power frequency component of the voltage fault traveling wave The initial polarity of the frequency component determines the fault direction of the first side of the high-voltage transmission line, and receives the ultra-high-speed traveling wave direction longitudinal protection device of the second high-voltage transmission line from the second side through the Ethernet communication device other fault information, determine the fault type and fault phase of the high-voltage transmission line according to the fault information on the first side and the other fault information on the second side, and determine whether to send a trip command to the first outlet relay ; The second high-voltage transmission line ultra-high-speed traveling wave direction longitudinal protection device obtains the second side of the high-voltage transmission line from the voltage and current from the second voltage transformer and the second current transformer respectively. The wave head polarity of the initial traveling wave of the current fault and the initial polarity of the power frequency component in the voltage fault traveling wave, and according to the wave head polarity of the current fault initial traveling wave of the second side and the power frequency component of the voltage fault traveling wave The initial polarity of the frequency component determines the fault direction of the second side of the high-voltage transmission line, and receives the ultra-high-speed traveling wave direction longitudinal protection device of the first high-voltage transmission line from the first side through the Ethernet communication device other fault information, determine the fault type and fault phase of the high-voltage transmission line according to the fault information on the second side and the other fault information on the first side, and determine whether to send a trip command to the second outlet relay ; The first Ethernet communication device transmits the fault information on the first side of the high-voltage transmission line to the second Ethernet communication device on the second side of the high-voltage transmission line through an optical fiber communication network, so as to realize the Interaction of the fault information at both ends of the high-voltage transmission line; The second Ethernet communication device transmits the fault information on the second side of the high-voltage transmission line to the first Ethernet communication device on the first side of the high-voltage transmission line through an optical fiber communication network; The first circuit breaker is installed on the high-voltage transmission line, receives a trip command from the ultra-high-speed traveling wave direction longitudinal protection device of the first high-voltage transmission line, and disconnects or closes the high-voltage transmission line; and The second circuit breaker is installed on the high-voltage transmission line, receives a trip command from the ultra-high-speed traveling wave direction longitudinal protection device of the second high-voltage transmission line, and disconnects or closes the high-voltage transmission line.

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