CN203929887U - The phase identification device of current transformation module in three-phase alternating current input power system - Google Patents

Abstract

The utility model discloses a phase recognition device of a current conversion module in a three-phase AC input power supply system, which comprises: a characteristic signal generating circuit connected with the output ends of the current conversion modules of each phase respectively, and receiving the output voltage of the current conversion module Signal, through the voltage signal, different phase characteristic signals are generated for the current transformation modules in different phases, and the current transformation module performs conversion processing, and the phase recognition circuit compares the phase characteristic signals after the transformation and processing of the current transformation module with the phase characteristic signals before processing. The voltage signal at the output terminal of the current conversion module is compared, and the comparison result is compared with a preset range to determine the phase of the current conversion module. The phase recognition device of the utility model is simple in design, easy to implement and low in cost, and effectively solves the problem that the devices for recognizing the phase of the load in a system powered by a three-phase AC power supply in the prior art are relatively complicated.

Description

Phase recognition device for current conversion module in three-phase AC input power system

technical field

The utility model relates to the field of power supplies, in particular to a phase identification device for a current conversion module in a three-phase AC input power supply system.

Background technique

In an ideal situation, the quality of the three-phase AC grid power supply is not affected by the load, but because the actual grid has a certain output impedance, if the loads on each phase of the three-phase grid are unbalanced, the output voltage will be distorted and The rise of the neutral line voltage will cause the pollution of the power grid and the decline of the power supply quality, and in severe cases, the automatic protection switch of the power grid will trip. The power supply system for communication is a kind of power conversion equipment between the grid and the electrical equipment. Its input terminal is connected to the grid, and its output terminal supplies power to the communication equipment. In the three-phase input type communication power supply system, if the loads at the input terminals of each phase can be automatically balanced, the pollution and adverse effects on the power grid can be reduced. For a communication power supply system connected to a three-phase power grid, if the current conversion module is a single-phase input module, it is necessary to realize the automatic balance control of the loads carried by each phase in the power system, and report the actual load borne by each phase to the user. There is an identification device corresponding to the position of the current conversion module and the phase line. However, the identification device in the prior art needs to use an isolation unit, so the circuit connection is relatively complicated.

Utility model content

The utility model provides a phase identification device for a current conversion module in a three-phase AC input power supply system to solve the problem of complicated circuit connection of the device for identifying the phase of the current conversion module in a system powered by a three-phase AC power supply in the prior art question.

The utility model provides a phase identification device for a current conversion module in a three-phase AC input power supply system, comprising:

A phase identification device for a current conversion module in a three-phase AC input power system, comprising:

The characteristic signal generation circuit is respectively connected to the output terminals of the current conversion modules of each phase, receives the voltage signal output by the current conversion module, and generates different phase characteristic signals for the current conversion modules on different phases through the voltage signal, by The current conversion module performs conversion processing;

The phase identification circuit compares the phase characteristic signal converted by the current conversion module with the voltage signal output by the current conversion module, compares the comparison result with a preset range, and determines the phase of the current conversion module.

Preferably, the phase characteristic signal is a voltage signal.

Preferably, the characteristic signal generating circuit includes a first switch, a second switch, and a first resistor, a second resistor, and a third resistor connected in series in sequence;

The two output terminals of the current transformation module are respectively connected to the first terminal of the first resistor and the second terminal of the third resistor;

The second end of the first resistor and the first end of the second resistor are connected to one end of the first switch, the second end of the second resistor and the first end of the third resistor are connected to the second switch One end of the first switch and the other end of the second switch are connected to an input end of the current conversion module, and the second end of the third resistor is connected to the current conversion module. The other input is connected;

Different phase characteristic signals are generated for current conversion modules of different phases by controlling the opening and closing of the first switch and the second switch.

Preferably, the resistance values of the first resistor, the second resistor and the third resistor are all the same.

Preferably, the current conversion module further includes: a signal sampling and conditioning circuit and a signal analog-to-digital conversion circuit;

The signal sampling and conditioning circuit performs amplification/attenuation and anti-interference signal conditioning on the phase characteristic signal, and sends the conditioned signal to the signal analog-to-digital conversion circuit;

The signal analog-to-digital conversion circuit performs analog-to-digital conversion on the signal output by the signal sampling and conditioning circuit to obtain corresponding digital information.

Preferably, the signal sampling and conditioning circuit is a differential amplifier circuit composed of operational amplifiers. The signal analog-to-digital conversion circuit is an analog-to-digital converter.

Preferably, the device also includes a power supply circuit;

The power supply circuit supplies power to the signal sampling and conditioning circuit, the signal analog-to-digital conversion circuit and the phase identification circuit.

Preferably, the characteristic signal generation circuit is installed on the power distribution wiring backplane, and the signal sampling and conditioning circuit, the signal analog-to-digital conversion circuit and the phase identification circuit are all integrated into the current conversion module.

Preferably, the current conversion module is a rectifier.

Preferably, a monitoring module is also included, and the monitoring module includes the phase identification circuit and the monitoring circuit;

The monitoring circuit controls the balance of loads on each phase line according to the phase of the current conversion module judged by the phase identification circuit, and provides query and display for the user.

The beneficial effects of the utility model are as follows:

The utility model connects the output ends of the current conversion modules of different phases with the characteristic signal generation circuit, and generates different phase characteristics for the current conversion modules at different phases through the characteristic signal generation circuit according to the voltage signal output by the output end of the current conversion module. The signal is converted and processed by the current conversion module, and finally the phase identification circuit compares the phase characteristic signal processed by the current conversion module with the voltage signal at the output end of the current conversion module to determine whether the current conversion module is in the three-phase grid Which phase (phase), the phase identification device of the utility model is simple in design, easy to implement, and low in cost, effectively solving the circuit connection of the device for identifying the phase of the load in a system powered by a three-phase AC power supply in the prior art more complex issue.

Description of drawings

Fig. 1 is a schematic structural diagram of a phase identification device of a current conversion module in a three-phase AC input power supply system according to an embodiment of the present invention;

Fig. 2 is a schematic diagram of the characteristic signal generating circuit when the current conversion module of the embodiment of the present invention is connected to phase A of the three-phase AC grid;

3 is a schematic diagram of a characteristic signal generating circuit when the current conversion module of the embodiment of the present invention is connected to the B phase of the three-phase AC power grid;

Fig. 4 is a schematic diagram of the characteristic signal generating circuit when the current conversion module of the embodiment of the present invention is connected to the phase C of the three-phase AC grid;

Fig. 5 is a schematic structural diagram of a phase identification device of a current conversion module in another three-phase AC input power supply system according to an embodiment of the present invention;

Fig. 6 is a schematic structural diagram of another phase identification device of a current conversion module in a three-phase AC input power supply system according to an embodiment of the present invention.

Detailed ways

In order to solve the complex circuit problem of the device for identifying the phase of the current conversion module in a system powered by a three-phase AC power supply in the prior art, the utility model provides a phase identification of a current conversion module in a three-phase AC input power supply system device, through the characteristic signal generating circuit to generate different voltage signals corresponding to different phase lines according to the voltage signal output by the current conversion module, after processing by the current conversion module, the phase identification circuit is based on the processed phase characteristic signal and the original input of the current conversion module The voltage signals are compared to determine which phase (phase) the current conversion module is in in the three-phase power grid. The phase identification device of the utility model has a simple structure, low cost and is easy to implement. Below in conjunction with accompanying drawing and embodiment, the utility model is described in further detail. It should be understood that the specific embodiments described here are only used to explain the utility model, not to limit the utility model.

The embodiment of the utility model provides a phase identification device of the current conversion module in the three-phase AC input power system, and Fig. 1 is a schematic structural diagram of the phase identification device of the current conversion module in the three-phase AC input power system of the embodiment of the utility model , as shown in Figure 1, the current conversion module phase identification device in the three-phase AC input power system according to the embodiment of the present invention includes: a characteristic signal generation circuit 101, a current conversion module 12 and a phase identification circuit 104, the following implementation of the utility model Each circuit of the example is described in detail.

The characteristic signal generating circuit 101 is respectively connected to the output terminals of the current conversion modules 12 of each phase, receives the voltage signal output by the current conversion module 12, and generates different voltage signals for the current conversion modules 12 on different phases through the voltage signal. The phase characteristic signal is converted and processed by the current conversion module 12;

The phase identification circuit 104 compares the phase characteristic signal converted by the current conversion module 12 with the voltage signal output by the current conversion module 12, compares the comparison result with a preset range, and judges that the current conversion module 12 the phase in which it is located. Specifically: the phase identification circuit 104 compares the ratio of the digital information of the phase characteristic signal converted by the current conversion module 12 and the digital information corresponding to the voltage signal output by the current conversion module itself with the preset range, and judges The phase of the current conversion module is obtained.

The utility model generates different phase characteristic signals corresponding to different phase lines through the characteristic signal generating circuit, and obtains corresponding digital quantity information after being processed by the current conversion module, and then the phase identification circuit obtains the digital quantity information according to the processing and the current conversion module itself The digital information corresponding to the output voltage signal is used to judge which phase (phase) the current conversion module is in in the three-phase power grid. The phase identification device of the utility model has a simple structure, low cost, and is easy to implement.

The characteristic signal generating circuit 101 of the embodiment of the present utility model is connected to the two output terminals of the current conversion module 12 in the power supply system or both ends of the output signal of which each current conversion module has a common terminal, and a phase is generated by the characteristic signal generating circuit 101 The characteristic signal, the phase characteristic signal is a preset voltage corresponding to the phase where the current conversion module 12 is located, and the preset voltage amplitudes are different for different phases where the current conversion module 12 is located. The phase characteristic signal in the embodiment of the utility model is a voltage signal. The current conversion module of the embodiment of the utility model is a rectifier.

Specifically, the characteristic signal generating circuit 101 includes a first switch K1 and a second switch K2, and a first resistor R1, a second resistor R2 and a third resistor R3 connected in series in sequence;

The two output ends of the current conversion module 12 are respectively connected to the first end of the first resistor R1 and the second end of the third resistor R2. When the current conversion modules 12 have a common end, the The output end and the common end of the current conversion module 12 are respectively connected to the first end of the first resistor R1 and the second end of the third resistor R2;

The second end of the first resistor R1 and the first end of the second resistor R2 are connected to one end of the first switch K1, the second end of the second resistor R2 and the first end of the third resistor R3 end is connected to one end of the second switch K2, the other end of the first switch K1 and the other end of the second switch K2 are both connected to one of the input ends of the current conversion module 12, and the third resistor R3 The second end of the second end is connected to the other input end of the current conversion module 12, by controlling the opening and closing of the first switch K1 and the second switch K2 to generate different phases for the current conversion modules 12 of different phases characteristic signal. The resistance values of the first resistor R1 , the second resistor R2 and the third resistor R3 in the embodiment of the present invention may be completely the same, or other arbitrary settings may be made according to actual needs.

The current conversion module 12 of the embodiment of the utility model further includes: a signal sampling and conditioning circuit 102 and a signal analog-to-digital conversion circuit 103;

Wherein, the signal sampling and conditioning circuit 102 performs amplification/attenuation and anti-interference signal conditioning on the phase characteristic signal, and sends the conditioned signal to the signal analog-to-digital conversion circuit 103; the signal sampling and conditioning circuit in the embodiment of the utility model is based on A differential amplifier circuit composed of operational amplifiers.

The signal analog-to-digital conversion circuit 103 performs analog-to-digital conversion on the signal output by the signal sampling and conditioning circuit 102 to obtain corresponding digital quantity information; the signal analog-to-digital conversion circuit in the embodiment of the utility model is an analog-to-digital converter, specifically, a current The existing control in the conversion module 12 is implemented with a processor built-in analog-to-digital converter.

The phase identification circuit 104 compares the digital quantity information converted by the signal analog-to-digital conversion circuit 103 and the digital quantity information corresponding to the voltage signal output by the current conversion module itself with the preset range, and determines where the current conversion module 12 is located. phase. That is, the phase identification circuit 104 compares the ratio of the digital information corresponding to the output voltage signal of the current conversion module itself to the digital information converted by the signal analog-to-digital conversion circuit 103 and the preset range to determine the current conversion module. 12's aspect. Specifically, the characteristic signal generation circuit 101 has different phase characteristic signals input by different current conversion modules, and the digital quantities obtained through the processing and conversion of the signal sampling and conditioning circuit 102 and the signal analog-to-digital conversion circuit 103 are also different, and the converted digital quantities The information is compared with the digital quantity of the known output voltage signal, and the phase of the current conversion module can be judged from the corresponding digital quantity range (reference: the phase characteristic signal voltage digital quantity is below 0% to 10% of the output voltage digital quantity Corresponding to phase A, 25-40% of the output voltage digital quantity corresponds to phase B, and 55-75% of the output voltage digital quantity corresponds to phase C), the phase identification circuit 104 uploads the judgment result to the monitoring module 13, and the monitoring module 13 can Control the number of current conversion modules (rectifiers) working on each phase line to achieve a balanced load. Customers can also check the phases where the rectifiers are located and the load status on each phase line.

The phase identification circuit 104 of the embodiment of the present invention is implemented by using the existing software in the control processor in the current conversion module 12 to carry out logical operation, or it is realized by the software identification in the existing processor in the monitoring module 13 .

An application scenario of the embodiment of the present invention is the phase identification of a single-phase rectifier in a three-phase input DC power supply system for communication. By installing a phase identification device on the rectifier and the wiring backplane of each phase of the three-phase AC power supply, the rectifier Judgment of the input phase, and report the judgment result to the monitoring system, which is used to control the load balance of each phase line, and can also be used for user query and display. The above-mentioned embodiments of the present invention will be described in detail below in combination with examples, taking a rectifier as an example.

The characteristic signal generation circuit 101 of the embodiment of the utility model is connected to both ends of the output voltage of the rectifier, and according to several sets of voltage signals with different amplitudes set up in advance, the voltage signals corresponding to different phases are selected and connected as a certain voltage signal through a toggle switch. The phase characteristic signal of the rectifier; preferably, in the utility model embodiment, wherein, the characteristic signal generating circuit 101 can be a voltage divider circuit composed of a group of equal resistance resistors connected in series, for the convenience of preset use, by dialing The code switch selects the phase characteristic signals corresponding to different phase lines.

Fig. 2 is a schematic diagram of the characteristic signal generation circuit when the current conversion module of the embodiment of the utility model is connected to the phase A of the three-phase AC grid, and Fig. 3 is the generation of the characteristic signal when the current conversion module of the embodiment of the utility model is connected to the phase B of the three-phase AC grid The schematic diagram of the circuit, Fig. 4 is the schematic diagram of the characteristic signal generation circuit when the current conversion module of the embodiment of the present invention is connected to the phase C of the three-phase AC grid, as shown in Fig. 2, Fig. 3 and Fig. 4:

As shown in Figure 4, phase A is the power supply for the rectifier. During the installation and wiring configuration, the switch K1 and K2 of the phase identification device are predetermined to be turned off. At this time, the voltage signal of the characteristic signal generating circuit is close to zero.

As shown in Figure 5, phase B is the power supply for the rectifier. During the installation and wiring configuration, the switch K1 of the phase identification device is opened and K2 is closed. At this time, the voltage signal of the characteristic signal generating circuit is about 1% of the output voltage of the rectifier. one third.

As shown in Figure 6, phase C is the power supply for the rectifier. During the installation and wiring configuration, the switch K1 of the phase identification device is scheduled to be closed and K2 is opened. At this time, the voltage signal of the characteristic signal generating circuit is about 100% of the output voltage of the rectifier. two thirds.

As shown in Fig. 2, Fig. 3 and Fig. 4, the signal sampling conditioning circuit 102 in the embodiment of the present invention includes two input ends and two output ends, wherein one input end is connected to one end of the rectifier output, and the other input end Connected to the other end of the rectifier in the power system (the common end of the module output on different phases), a circuit that amplifies, attenuates, and filters the phase characteristic signal from the characteristic signal generation circuit 101. The signal sampling and conditioning circuit 102 can be integrated into the rectifier.

The signal analog-to-digital conversion circuit 103 is connected to one of the output terminals of the signal sampling and conditioning circuit 102 and the ground terminal, and is used for converting the analog signal output by the signal sampling and conditioning circuit 102 into digital information. The signal analog-to-digital conversion circuit 103 can be integrated into the rectifier and implemented by using an existing processor-built analog-to-digital converter.

The phase recognition circuit 104 is connected to the output of the signal analog-to-digital conversion circuit 103, and is used to judge the range of the digital value output by the signal analog-to-digital conversion circuit 103, and compare and identify the phase corresponding to the preset feature. The phase recognition circuit 104 can be integrated into the rectifier and realized by software by means of an existing processor, or realized in the monitoring module 13 .

Fig. 5 is a schematic structural diagram of a current conversion module phase identification device in another three-phase AC input power system according to an embodiment of the present invention; as shown in Fig. 5, in the embodiment of the present invention, the current conversion module 12 includes a characteristic Generating circuit 101, signal sampling conditioning circuit 102, signal analog-to-digital conversion circuit 103, phase recognition circuit 104 and power supply circuit 105, the signal sampling conditioning circuit 102, the signal analog-to-digital conversion circuit 103 and the described signal sampling conditioning circuit 105 are provided by the power supply circuit 105 The phase identification circuit 104 is powered. And the characteristic signal generating circuit 101 is installed on the power distribution wiring backplane 11 . The phase identification circuit 104 reports the judgment result to the monitoring module 13, and the monitoring module 13 controls the balance of the load on each phase line, and provides the user with query and display.

Fig. 6 is a schematic structural diagram of another three-phase AC input power supply system in the embodiment of the utility model, as shown in Fig. 6, compared with the embodiment in Fig. 5, in the embodiment of the utility model In this method, the phase identification circuit 104 is integrated in the monitoring module 13, and the monitoring module 13 also includes a monitoring circuit 106 according to the phase identification circuit 104 to determine that the phase where the current conversion module 12 is located controls the balance of the load on each phase line, And for users to query and display.

It can be seen from the above processing and specific embodiments that a certain phase in the three-phase AC input power supply system outputs a DC voltage after passing through the rectifier, and the DC voltage can be output by default after passing through the characteristic signal generating circuit 101 of the phase identification device. The corresponding voltage signal is sent to the signal sampling and conditioning circuit 102, the signal output by the signal sampling and conditioning circuit 102 is passed through the signal analog-to-digital conversion circuit 103 to obtain a digital quantity, and the phase identification circuit 104 is based on the range of the digital quantity and the corresponding digital quantity of the output voltage The phase of the rectifier in the three-phase power supply can be judged, and only one path is needed for more phases. The phase identification device in the three-phase AC power supply system according to the embodiment of the utility model is simple in design, easy to implement, and low in cost, and can be popularized and applied to other occasions that need to identify the phase of the three-phase AC power supply.

The utility model can at least achieve the following beneficial effects:

The utility model generates different voltage signals corresponding to different phase lines through the characteristic signal generation circuit, and obtains corresponding digital quantity information after being processed by the signal sampling conditioning circuit and the signal analog-to-digital conversion circuit, and the phase identification circuit according to these digital quantity information and current The voltage signal output by the conversion module itself is used to determine which phase (phase) the current conversion module is in in the three-phase grid. The phase identification device of the utility model is simple in design, easy to implement, and low in cost.

Although preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various improvements, additions and substitutions are possible, and therefore, the scope of the present invention should not be limited to the above-described embodiments.

Claims (10)

1. A phase identification device of a current conversion module in a three-phase AC input power system, characterized in that it comprises: The characteristic signal generation circuit is respectively connected to the output terminals of the current conversion modules of each phase, receives the voltage signal output by the current conversion module, and generates different phase characteristic signals for the current conversion modules on different phases through the voltage signal, by The current conversion module performs conversion processing; The phase identification circuit compares the phase characteristic signal converted by the current conversion module with the voltage signal output by the current conversion module, compares the comparison result with a preset range, and judges where the current conversion module is located. phase. 2. The device according to claim 1, wherein the phase characteristic signal is a voltage signal. 3. The device according to claim 2, wherein the characteristic signal generating circuit comprises a first switch, a second switch, and a first resistor, a second resistor and a third resistor connected in series in sequence; The two output terminals of the current transformation module are respectively connected to the first terminal of the first resistor and the second terminal of the third resistor; The second end of the first resistor and the first end of the second resistor are connected to one end of the first switch, the second end of the second resistor and the first end of the third resistor are connected to the second switch One end of the first switch and the other end of the second switch are connected to an input end of the current conversion module, and the second end of the third resistor is connected to the current conversion module. The other input is connected; Different phase characteristic signals are generated for current conversion modules of different phases by controlling the opening and closing of the first switch and the second switch. 4. The device according to claim 3, wherein the resistance values of the first resistor, the second resistor and the third resistor are all the same. 5. The device according to claim 1, wherein the current conversion module further comprises: a signal sampling conditioning circuit and a signal analog-to-digital conversion circuit; The signal sampling and conditioning circuit performs amplification/attenuation and anti-interference signal conditioning on the phase characteristic signal, and sends the conditioned signal to the signal analog-to-digital conversion circuit; The signal analog-to-digital conversion circuit performs analog-to-digital conversion on the signal output by the signal sampling and conditioning circuit to obtain corresponding digital information. 6. The device according to claim 5, characterized in that, The signal sampling and conditioning circuit is a differential amplifier circuit composed of an operational amplifier; The signal analog-to-digital conversion circuit is an analog-to-digital converter. 7. The device according to claim 5, further comprising a power supply circuit; The power supply circuit supplies power to the signal sampling and conditioning circuit, the signal analog-to-digital conversion circuit and the phase identification circuit. 8. The device of claim 5, wherein: The characteristic signal generation circuit is installed on the power distribution wiring backplane, and the signal sampling and conditioning circuit, the signal analog-to-digital conversion circuit and the phase identification circuit are all integrated into the current conversion module. 9. The device according to any one of claims 1-8, wherein the current conversion module is a rectifier. 10. The device according to any one of claims 1-7, further comprising a monitoring module, the monitoring module comprising the phase identification circuit and a monitoring circuit; The monitoring circuit controls the balance of loads on each phase line according to the phase of the current conversion module judged by the phase identification circuit, and provides query and display for the user.