CN201937579U - Power grid communication system based on medium-voltage PLC technology - Google Patents

Abstract

A power network communication system based on medium-voltage power carrier technology, which includes: the master station is composed of interconnected workstations and servers, and the server is connected to the optical transceiver of the master station through the optical modem of the master station; the master station Start the calling and testing process, and send the calling and testing command to the substation carrier master station; the substation carrier master station, which is composed of substation optical transceiver, substation optical Modem and master station carrier machine, and the substation optical transceiver is connected to the main station carrier machine through the substation optical Modem ; Among them, the substation optical terminal is connected to the optical terminal of the master station, and the carrier machine of the master station receives the calling test command of the master station, converts it into a carrier signal and couples it to the cable outlet line, and transmits it to the carrier slave station; at least one carrier slave station , which is composed of a transformer, a power distribution collection device, a slave station carrier machine and a filter device; the power distribution collection device obtains a test command from the output line of the transformer and forwards it to the slave station carrier machine.

Description

Power Network Communication System Based on Medium Voltage Power Carrier Technology

technical field

The utility model relates to a power network communication system based on medium-voltage power carrier technology.

Background technique

With the further deepening of the power system reform, the degree of enterprise and marketization of power system management and operation is increasingly strengthened, and the degree of automation of distribution network is getting higher and higher. Load control management, station area management, meter reading system, reactive power investment Cutting, low-voltage meter reading system and other projects spread all over the distribution network.

What follows is the management, maintenance, upgrade, etc. of each system, among which the channel part is the part with the largest investment and the most complicated. The requirements for the communication system in the distribution automation part depend on the scale, complexity and expected automation level of the distribution network automation project. Generally speaking, the distribution network automation project requires the communication system in the following points: communication reliability, construction cost, communication speed, two-way communication capability, and the ease of maintenance of the communication system.

At present, the load management system that is widely used in the province has played an important role in reducing line loss and improving economic benefits. However, with the promulgation of the "05 version load control protocol" of the State Grid Corporation of China, the amount of information to be collected by the system has suddenly increased. , so the current means of communication has caused a certain delay in the real-time collection. Therefore, it is absolutely necessary to adopt new means of communication, and 10KV power line carrier is a desirable means of communication. The power line carrier communication technology has its own unique networking method, and grouping by frequency is a communication scheme that conforms to the limited resources of the carrier line. The carrier network is a "pyramid" or "tree structure" network topology model, the communication and control processes between the upper and lower layers can be processed in parallel, and the concept of "subgroup" is adopted for complex power grids to improve It improves the timeliness of data transmission, effectively eliminates the bottleneck of data transmission, and facilitates the rapid diagnosis of network transmission failure points.

Therefore, actively adopting advanced information collection technology, network technology, and decision-making support technology, giving full play to the advantages of all parties, establishing a number of demonstration projects at a high starting point, and avoiding the existing low-level redundant development are of great significance for promoting the leapfrog development of power system informatization. very important strategic significance.

Overcome various difficulties in the transmission of carrier signals at 10KV, such as: the structure of the distribution network is relatively complex, there are many T contacts, and the line structure changes greatly, wave traps cannot be used, and the randomness of line load switching causes the randomness of signal attenuation Very big wait.

Utility model content

The purpose of the utility model is to provide a power network communication system based on medium-voltage power carrier technology that does not require wave blocking and has a relatively simple carrier channel.

To achieve the above object, the utility model adopts the following technical solutions: it comprises:

Bureau master station, it is made up of interconnected workstation and server, and described server connects bureau master station optical end machine through bureau master station optical Modem; Described bureau master station starts calling and testing process, and sends calling and testing order to transformer substation carrier master stand;

Substation carrier master station, it is made up of substation optical terminal, substation optical Modem and main station carrier machine, described substation optical terminal is connected main station carrier machine through substation optical Modem; After receiving the test command from the master station, convert it into a carrier signal and couple it to the cable outlet line, and transmit it to the carrier slave station;

At least one carrier slave station, which is made up of a transformer, a power distribution acquisition device, a slave station carrier machine and a filter device; the power distribution acquisition device obtains a call test command from the transformer output line and forwards it to the slave station carrier machine, and the slave station The carrier machine analyzes the call-to-test command and outputs response information, and the response information is filtered by the filter device and sent back to the substation carrier master station and bureau master station.

Both the master station carrier machine and the slave station carrier machine include:

Receive filter, filter the received call-to-test command;

Sending filter, which filters the response information to be sent;

A power amplification module, which amplifies the power of the response information to be sent;

The modulation and demodulation module performs DPSK encoding and decoding operations on the calling test command and the response information to be sent;

The digital signal processing module processes the calling test command and response information after modulation and demodulation; and the digital signal processing module communicates with the upper computer through the interface circuit.

The interface circuit includes an RS232 interface circuit and an RS485 interface circuit.

The digital signal processing module is also connected with the watchdog module.

Each carrier slave station is also connected to at least one substation.

In the power distribution acquisition device, the inductive coupler is coupled to the cable shielding layer.

The utility model adopts the above technical solution, DLC-2100 power line multiple access digital carrier technology, adopts DPSK modulation technology, the whole network does not need wave blocking, the carrier channel is relatively simple, only includes: DLC-2100 carrier communication machine, coupling equipment (coupling capacitor , coupled inductance), power distribution lines; in addition, due to the low transmission power and high receiving sensitivity, the requirements for coupling equipment are also low.

Description of drawings

Fig. 1 is the overall structural representation of the utility model;

Fig. 2 is a functional block diagram of the master station carrier machine and the slave station carrier machine of the present invention.

Fig. 3 is a structural diagram of the power distribution collection device of the present invention.

Detailed ways

As shown in Figure 1, the utility model uses a 10KV power supply line to transmit data. The main station of the distribution network uses polling to communicate with the communication terminal, and the response mode is used to complete. The utility model is composed of three parts: a bureau master station, a substation carrier master station, and at least one carrier carrier slave station. The specific description and communication process are as follows.

The office master station is composed of interconnected workstations and servers. The above-mentioned servers are connected to the optical transceivers of the office master station through the optical Modem of the office master station. The front-end computer of the master station starts the call-to-test process, sends out the call-to-test command, and transmits it to the corresponding substation carrier master station through the optical transmitter through the fiber channel.

Substation carrier main station is composed of substation optical transceiver, substation optical Modem and main station carrier machine. The above-mentioned substation optical transceiver is connected to the main station carrier machine through the substation optical Modem; among them, the substation optical transceiver is connected to the main station optical transceiver, and the main station carrier machine converts it into a carrier signal and couples it to the cable outlet after receiving the calling test command from the bureau master station. On, send to the carrier slave station.

At least one carrier slave station, which is composed of a transformer T, a power distribution collection device, a carrier machine of a slave station and a filtering device F. The above-mentioned power distribution acquisition device obtains the test call command from the output line of the transformer and forwards it to the carrier machine of the slave station. A collection terminal is set in the carrier machine of the slave station. After analyzing the call test command, the collection terminal outputs response information. It is transformed into a carrier signal from the carrier machine of the substation, and then sent back to the substation carrier master station and bureau master station after being filtered by the filter device F0. The above-mentioned carrier slave stations can be set according to local actual conditions. As shown in FIG. 1, there are three carrier slave stations, and of course there can be five, ten or even more. It should be noted that, the carrier devices in each carrier slave station share channel resources in a time-division multiplexing manner. In addition, each carrier slave station can also be connected with multiple sub-stations, and the sub-stations serve as the subordinate communication units of the carrier slave station, which can facilitate the call-and-test order to reach smaller and more specific power grid departments.

After receiving the uplink response information, the carrier machine of the main station in the carrier main station of the substation converts the response information into digital-to-analog conversion, converts the electrical signal into an optical signal through the optical transmitter, and then sends it back to the main station through the optical fiber channel.

After the optical receiver of the master station receives the response information, it becomes an electrical signal and sends it to the front-end processor of the master station.

As shown in Figure 2, the above-mentioned master station carrier machine and slave station carrier machine both include a receiving filter, a sending filter, a power amplification module, a modulation and demodulation module, a digital signal processing module and a watchdog module. Among them, the receiving filter will filter the received test command; the modulation and demodulation module will perform DPSK modulation on the filtered test command, so that the whole network does not need to block the wave, and the carrier channel is relatively simple. Next, the digital signal processing module processes the modulated test command. The above processing includes interleaving error correction, balance comparison, etc., and the above processing processes are well known to those skilled in the art. In addition, the digital signal processing module communicates with the host computer through an interface circuit. The host computer can be a collection terminal device, and the interface circuit includes an RS232 interface circuit and an RS485 interface circuit. After analysis and processing, the acquisition terminal replies with response information. The response information is first sent to the digital signal processing module for processing through the RS232 interface circuit or RS485 interface circuit, then demodulated through the modulation and demodulation module, and then amplified through the power amplification module, and finally It is filtered by the sending filter to prevent the carrier signal from being interfered by external clutter during transmission. It should be noted that the utility model is also equipped with a watchdog module, which can reset the carrier machine forcibly when the carrier signal is severely interfered by the outside world.

As shown in FIG. 3 , in the power distribution acquisition device of the present invention, an inductive coupler is coupled to the cable shielding layer 2 . Generally speaking, a 10KV power transmission cable 1 is composed of a shielding layer 2, an insulating layer 3 and an inner core 4 in sequence from outside to inside. The inductive coupler 5 is installed on the utility pole, and its high-voltage end is connected to the B phase on the 10KV line 1 . Connect one end of the 16MM ² aluminum core wire to the B-phase line, and screw the other end to the high-voltage port of the coupling device. The channel line is led out from the cable port of the coupling device and connected to the load terminal box. The installation height of the integrated coupling device should be as high as possible under the premise of safety. It should be noted that the ground terminal of the integrated coupling device must be well grounded.

Claims (6)

1. A power grid communication system based on medium-voltage power carrier technology, characterized in that it includes: Bureau master station, it is made up of interconnected workstation and server, and described server connects bureau master station optical end machine through bureau master station optical Modem; Described bureau master station starts calling and testing process, and sends calling and testing order to transformer substation carrier master stand; Substation carrier master station, it is made up of substation optical terminal, substation optical Modem and main station carrier machine, described substation optical terminal is connected main station carrier machine through substation optical Modem; After receiving the test command from the master station, convert it into a carrier signal and couple it to the cable outlet line, and transmit it to the carrier slave station; At least one carrier slave station, which is made up of a transformer, a power distribution acquisition device, a slave station carrier machine and a filter device; the power distribution acquisition device obtains a call test command from the transformer output line and forwards it to the slave station carrier machine, and the slave station The carrier machine analyzes the call-to-test command and outputs response information, and the response information is filtered by the filter device and sent back to the substation carrier master station and bureau master station. 2. The power network communication system based on medium-voltage power carrier technology according to claim 1, wherein said master station carrier machine and slave station carrier machine both include: Receive filter, filter the received call-to-test command; Sending filter, which filters the response information to be sent; A power amplification module, which amplifies the power of the response information to be sent; The modulation and demodulation module performs DPSK encoding and decoding operations on the calling test command and the response information to be sent; The digital signal processing module processes the calling test command and response information after modulation and demodulation; and the digital signal processing module communicates with the upper computer through the interface circuit. 3. The power network communication system based on medium-voltage power carrier technology according to claim 2, wherein the interface circuit includes an RS232 interface circuit and an RS485 interface circuit. 4. The power network communication system based on medium voltage power carrier technology according to claim 2, characterized in that: said digital signal processing module is also connected with a watchdog module. 5. The power network communication system based on medium-voltage power carrier technology according to any one of claims 1-4, characterized in that each carrier slave station is also connected to at least one sub-station. 6. The power network communication system based on medium-voltage power carrier technology according to claim 1, characterized in that: in the power distribution acquisition device, an inductive coupler is coupled to the cable shielding layer.

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