CN205647023U - Supply power distribution monitoring system - Google Patents

Abstract

The utility model discloses a monitoring system for power supply and distribution, comprising: an on-site monitoring subsystem, a communication network and a monitoring center; Quantity and switching value, and transmit the above collected data to the monitoring center through the communication network; the monitoring center receives and stores, counts, analyzes and processes the collected data information and issues control instructions through the communication network. It improves management efficiency and reliability of system power supply, and provides information needed to reduce power consumption, reduce cost equipment investment and potential consumption of equipment operation. The power supply and distribution monitoring system has established a complete monitoring system for transformer equipment and power distribution equipment through the collection, storage, statistics, analysis, and processing of power parameters. During the real-time monitoring process, abnormal phenomena are found in time and effective measures are taken for equipment transformation. Or compensation to avoid fault expansion and avoid losses.

Description

A power supply and distribution monitoring system

technical field

The utility model relates to the field of power systems, in particular to a power supply and distribution monitoring system.

Background technique

The traditional power supply and distribution system has simple equipment and control, low degree of automation, and requires special personnel on duty and patrolling. If a fault occurs, it needs to be searched along the line, which cannot meet the needs of the rapid development of modern society and economy.

With the development of the power distribution system, the original manual monitoring and inspection can no longer keep up with the current development process, and there are still many inconveniences and defects, which need to be improved urgently. In order to solve these problems, relevant manufacturers have tried their best to find a solution, but there has been no suitable design for a long time. This is obviously a problem that relevant manufacturers are eager to solve.

Contents of the invention

In order to overcome the deficiencies in the above-mentioned prior art, the purpose of this utility model is to provide a power supply and distribution monitoring system, including: on-site monitoring subsystem, communication network and monitoring center;

The on-site monitoring subsystem is used to collect analog quantities of on-site transformer equipment and power distribution equipment compatible with the transformer equipment, including: current, voltage, active power, reactive power, coil temperature, oil temperature on each side of the transformer ; Current, active power, reactive power of the power supply line; voltage and frequency of the bus bar; current of the section/bus coupler; three-phase voltage, three-phase current, zero-sequence voltage, zero-sequence current of the power supply line, and field equipment The switching value includes: high voltage circuit breaker position, isolating switch, grounding knife switch position, 380V circuit breaker switch position, DC main circuit switch position, protection action total signal; substation accident total signal, local/remote transfer switch position , circuit breaker operating mechanism abnormal signal, control circuit disconnection signal, protection alarm signal, protection device fault signal, power supply equipment abnormal signal, automatic device abnormal signal, DC system abnormal signal, fire alarm device fault signal, the on-site monitoring The subsystem transmits the collected data above to the monitoring center through the communication network;

The communication network is used to transmit the on-site data collected by the on-site monitoring layer to the monitoring center;

The monitoring center receives and stores, counts, analyzes and processes the collected data information, and issues control instructions through the communication network.

Preferably, the on-site monitoring subsystem includes: a transformer high-voltage side current detection module, a transformer medium-voltage side current detection module, and a current filtering module;

The transformer high-voltage side current detection module is used to detect the three-phase current on the high-voltage side of the transformer and the zero-sequence current on the high-voltage side;

The transformer medium-voltage side current detection module is used to detect the three-phase current of the transformer medium-voltage side and the zero-sequence current of the medium-voltage side;

The current filtering module filters the collected current;

The monitoring center includes: a transformer zero-sequence current calculation module, a transformer zero-sequence differential judgment module, a transformer zero-sequence differential action module, and a zero-sequence voltage blocking module;

The zero-sequence voltage blocking module is used to detect the zero-sequence voltage when a ground fault occurs in the transformer;

The transformer zero-sequence current calculation module is used to obtain the three-phase current on the high-voltage side of the transformer and the three-phase current on the medium-voltage side of the transformer, through I _op.0 =K ₁ *I _0G +K ₂ *I _0H , wherein, K ₁ Take 1~ _1.2 , K2 take 1.1~1.3, get the zero-sequence current on both sides of the transformer; I _0G is the zero-sequence current on the high-voltage side, I _0H is the zero-sequence current on the medium-voltage side, and I _op.0 is the reference zero-sequence on the high-voltage side current;

The transformer zero-sequence differential determination module is used to determine whether the zero-sequence differential protection condition is met, and when I _op is greater than I _op.0 and I _op is greater than (0.6-0.9)*I _zd , the zero-sequence voltage is blocked When the module detects the zero-sequence voltage, the transformer zero-sequence differential action module starts the transformer zero-sequence protection;

I _op is the differential current of zero-sequence differential protection;

I _zd is the braking current of differential protection ratio.

Preferably, the monitoring center includes: a transformer braking current calculation module;

The transformer braking current calculation module is used to obtain the three-phase current on the high-voltage side of the transformer and the three-phase current on the medium-voltage side of the transformer, through I _zd =K ₃ *I _G -K ₄ *I _H , where K ₃ is 0.7 ～1.3, K ₄ takes 0.6～1.2 to get the differential protection ratio braking current;

I _G ＝max{│I _AG │,│I _BG │,│I _CG │},

Among them, I _AG , I _BG , and I _CG are the three-phase currents on the high-voltage side;

I _D =max{│I _AH │,│I _BH │,│I _CH │},

in

I _AG , I _BG , and I _CG are the three-phase currents at the high voltage side;

I _AH , I _BH , and I _CH are three-phase currents on the medium voltage side.

Preferably, the monitoring center includes: an IP encoding module;

The IP encoding module is used to set the unique IP address of each monitoring unit of the on-site monitoring subsystem;

The on-site monitoring subsystem includes: a humidity sensor, a transformer monitoring unit,

The humidity sensor is used for real-time monitoring of the humidity in the substation room and power distribution room;

The transformer monitoring unit is used for real-time monitoring of the running state of the transformer in the substation.

Preferably, the transformer monitoring unit adopts a camera device;

The camera device includes: a video acquisition module, a video decomposition module, a heat sensing module, and a video transmission module;

The video acquisition module is used to take images of the transformer room and the power distribution room;

The heat sensing module is used to sense the temperature of the transformer in the transformer room and the temperature of the power distribution cabinet in the power distribution room;

The video decomposition module is used to decompose the ingested video picture in a frame-by-frame manner;

The video transmission module is used to transmit each frame of image and the thermal information sensed by the thermal sensing module to the monitoring center;

The monitoring center includes: a standard image setting module, an image comparison module, an image synthesis unit, a video receiving module, and a temperature alarm module;

The standard image setting module is used to set the standard images of the transformer room and the power distribution room;

The video receiving module is used to receive images transmitted by the video transmission module and heat information sensed by the heat sensing module;

The image synthesis unit is used to combine each frame of images received to form a complete image of the transformer room and power distribution room;

The image comparison module is used to compare the received images of the transformer room and the power distribution room with the standard images of the transformer room and the power distribution room respectively. When there is a difference between the received image information and the standard image information, Issue a prompt message;

The temperature alarm module is used for sending out an alarm message when the heat information sensed by the heat sensing module exceeds a set temperature.

Preferably, the camera includes: a face recognition module;

The monitoring center includes: a human body identification module;

The face recognition module is used to recognize the face of the person entering the transformer room or power distribution room, and transmits it to the monitoring center through the video transmission module;

The human body identification module is used to recognize the person entering the transformer room or power distribution room according to the received facial recognition information and combined with the thermal sensor module to sense the temperature information of the human body.

Preferably, the monitoring center includes: a time setting module, a human body judgment alarm module;

The time setting module is used to set the running time period, non-running time period and maintenance time period of the power supply system;

The human body judgment alarm module is used to identify persons entering the transformer room or power distribution room by the human body identification module during the running time period of the power supply system, and the human body judgment alarm module sends out a safety alarm; during the non-running time period of the power supply system , the human body identification module recognizes that a person enters the transformer room or power distribution room, and the human body identification alarm module sends out an anti-theft alarm; during the power supply system maintenance time period, the maintenance personnel are monitored for maintenance operations.

Preferably, the video transmission module includes: a data sending unit, a sending clock, and an error checking unit;

The data sending unit is used to send data in parallel under the drive of the sending clock, sending bit 0 to bit 3 on the rising edge of the clock, sending bit 4 to bit 7 on the falling edge, and completing the data sending of one byte per clock cycle ;

The error checking unit is used for accumulating the eight-bit parallel data to be sent every sixteen consecutive clock cycles, and taking the low eight bits of the accumulated sum as a checksum byte, and each passing through sixteen consecutive clock cycles The seventeenth clock cycle sends a verification accumulation clearing signal, and sends a null byte at the eighteenth clock; the data frame video signal sent by the data sending unit includes: data frame video signal, checksum byte, Null bytes.

Preferably, the video receiving module includes: a data receiving unit, a receiving error checking unit;

The data receiving unit is used to receive data in parallel at the same frequency as the sending clock.

The receiving error checking unit is used to output the eight-bit parallel data of each sixteen consecutive clock cycles as the received data, and at the same time accumulate and sum the data of each sixteen consecutive clock cycles to obtain a local calculation checksum, The locally calculated checksum is compared with the received 8-bit data of the seventeenth clock cycle. If the comparison result is the same, the currently received data is correct; otherwise, the data is wrongly reported to the upper module.

Preferably, the monitoring center includes: an operation report generation module and a peak and valley statistics module;

The operation report generation module is used to automatically generate the operation duty record report, the shift record report, the equipment account, the relay protection fixed value table, the equipment maintenance record table, the load day, month and year report;

The peak-valley statistical module is used to generate peak-valley level electric energy statistics by hour, day, month, and year, and perform time-of-use charging statistics for electric energy according to peak, valley, and normal periods.

As can be seen from the above technical solutions, the utility model has the following advantages:

The power supply and distribution monitoring system improves the management efficiency and the reliability of the system power supply, and provides the information needed to reduce the cost of electric energy, reduce the cost of equipment investment and the potential consumption of equipment operation.

The power supply and distribution monitoring system has established a complete monitoring system for transformer equipment and power distribution equipment through the collection, storage, statistics, analysis, and processing of power parameters. During the real-time monitoring process, abnormal phenomena are found in time and effective measures are taken for equipment transformation. Or compensation to avoid fault expansion and avoid losses.

Description of drawings

In order to illustrate the technical solution of the utility model more clearly, the accompanying drawings that need to be used in the description will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the utility model. Ordinary technicians can also obtain other drawings based on these drawings on the premise of not paying creative work.

Figure 1 is an overall schematic diagram of the power supply and distribution monitoring system;

Fig. 2 is a schematic diagram of an embodiment of a power supply and distribution monitoring system.

detailed description

In order to make the purpose, features and advantages of the utility model more obvious and understandable, the technical solutions protected by the utility model will be clearly and completely described below using specific embodiments and accompanying drawings. Obviously, the following description The embodiments are only a part of the embodiments of the present utility model, but not all embodiments. Based on the embodiments in this patent, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of this patent.

This embodiment provides a power supply and distribution monitoring system, as shown in FIG. 1 , including: an on-site monitoring subsystem 1, a communication network 2 and a monitoring center 3;

On-site monitoring subsystem 1 is used to collect analog quantities of on-site transformer equipment and power distribution equipment compatible with the transformer equipment, including current, voltage, active power, reactive power, coil temperature, and oil temperature on each side of the transformer; The current, active power, and reactive power of the power supply line; the voltage and frequency of the bus bar; the current of the section/bus coupler; Switching value, switching value includes: high voltage circuit breaker position, isolating switch, grounding switch position, 380V circuit breaker switch position, DC main circuit switch position, protection action total signal; substation accident total signal, local/remote transfer switch position, Circuit breaker operating mechanism abnormal signal, control circuit disconnection signal, protection alarm signal, protection device fault signal, power supply equipment abnormal signal, automatic device abnormal signal, DC system abnormal signal, fire alarm device fault signal, the on-site monitoring subsystem will The above-mentioned data collected are transmitted to the monitoring center 3 through the communication network;

The communication network 2 is used to transmit the on-site data collected by the on-site monitoring layer to the monitoring center 3; the monitoring center 3 receives and stores, counts, analyzes and processes the collected data information and issues control instructions through the communication network.

The monitoring center 3 can store, count, analyze and process the status of the power supply system. When there is a failure or accident in the power supply system, an alarm can be given. The content of the alarm includes the alarm of analog quantity over-limit and the alarm of switch state displacement. The alarm is divided into general alarm and accident alarm. General alarms include analog quantity over-limit alarms, switch quantity forecast signal alarms and fault alarms for microcomputer protection itself. Accident alarm refers to the protection action and circuit breaker trip signal caused by the accident. At this time, the monitoring system automatically displays the relevant screen display. The tripped circuit breaker in the screen changes color and flashes, and a special alarm sound is issued. The alarm sound is confirmed by the operator. Finally, it can be manually reset, and the alarm sound can emit different sounds according to different types of alarm signals.

In addition, when the current and voltage of the power supply system exceed the limit, the screen flashes to prompt, and the current limit value is displayed in the alarm prompt window. For events such as switch displacement, protection action, and protection alarm, the corresponding content is displayed in the alarm prompt box. The monitoring center 3 can print and record all the above-mentioned events and write them to disk for storage.

In this embodiment, as shown in Figure 2, the monitoring center 3 includes: an IP encoding module;

The IP coding module is used to set the unique IP address of each monitoring unit of the on-site monitoring subsystem; the IP address can accurately identify the source of the data uploaded by the system, due to the uniqueness of the IP address of the monitoring unit in the monitoring system network, thus The security and reliability of data packet transmission in the system network are guaranteed.

The on-site monitoring subsystem 1 includes: a humidity sensor, a transformer monitoring unit, the humidity sensor is used for real-time monitoring of the temperature and humidity in the substation room and power distribution room; the transformer monitoring unit is used for real-time monitoring of the operation status of the transformer in the substation room .

In this embodiment, the transformer monitoring unit adopts a camera device; the camera device includes: a video acquisition module 11, a video decomposition module 12, a heat sensing module 13, and a video transmission module 14;

The video acquisition module 11 is used to take images of the transformer room and the power distribution room;

The heat sensing module 13 is used to sense the temperature of the transformer in the transformer room and the temperature of the power distribution cabinet in the power distribution room; the video decomposition module 12 is used to decompose the captured video picture in a frame-by-frame manner; the video transmission module 14 is used to Each frame of image and the temperature information sensed by the temperature sensing module 13 are transmitted to the monitoring center;

The monitoring center 3 includes: a standard image setting module 32, an image comparison module 33, an image synthesis unit 34, a video receiving module 31, and a temperature alarm module 35;

Standard image setting module 32 is used to set the standard image of transformer room and power distribution room;

The video receiving module 31 is used for receiving the image transmitted by the video transmission module 14 and the heat information sensed by the heat sensing module 13;

The image synthesis unit 34 is used for synthesizing each frame of images received into images in the complete transformer room and power distribution room;

The image comparison module 33 is used to compare the received images of the transformer room and the power distribution room with the standard images of the transformer room and the power distribution room respectively, and when there is a difference between the received image information and the standard image information, send Prompt information;

The temperature alarm module 35 is used for sending out an alarm message when the heat information sensed by the heat sensing module exceeds a set temperature.

By acquiring the images of the transformer room and power distribution room and uploading them to the monitoring center, the image comparison module 33 of the monitoring center compares the received images of the transformer room and power distribution room with the standard images of the transformer room and power distribution room For comparison, when there is a difference between the received image information and the standard image information, a prompt message is issued; this enables the monitoring center to know the information of the transformer room and power distribution room in real time to ensure the normal operation of the power supply equipment.

In this embodiment, the camera includes: a face recognition module 15;

The monitoring center includes: a human body recognition module 36; a human face recognition module 15 is used to identify the face of a person entering a transformer room or a power distribution room, and is transmitted to the monitoring center 3 through a video transmission module 14; the human body recognition module 36 is used to The face information is recognized, combined with the temperature information of the human body sensed by the heat sensing module 13, to identify the person entering the transformer room or power distribution room. The monitoring center can monitor personnel entering the transformer room and power distribution room in real time.

In this embodiment, the monitoring center 3 includes: a time setting module 38, a human body judgment and alarm module 37;

The time setting module 38 is used to set the operating time period, non-operating time period and maintenance time period of the power supply system;

The human body identification alarm module 37 is used for the human body identification module identification personnel to enter the transformer room or power distribution room during the running time period of the power supply system, and the human body identification alarm module 37 sends a safety alarm; 36 When the identification personnel enters the transformer room or power distribution room, the human body judgment alarm module 37 sends out an anti-theft alarm; during the power supply system maintenance time period, the maintenance personnel are monitored for maintenance operations.

During the running time of the power supply system, after personnel enter the transformer room or power distribution room, a safety alarm will be issued to prevent personnel from getting an electric shock. During the non-operating period of the power supply system, some people are prevented from stealing the transformer room or power distribution room, so that the monitoring center can monitor the status of the transformer room or power distribution room in real time. During the maintenance period of the power supply system, monitor the maintenance work of the maintenance personnel to prevent safety accidents for the maintenance personnel, and after switching from the maintenance time to the running time, if there are maintenance personnel in the transformer room or power distribution room that have not been evacuated, the human body Judgment alarm module 37 sends an alarm, prompting maintenance personnel to evacuate.

In this embodiment, the video transmission module includes: a data sending unit, a sending clock, and an error checking unit;

The data sending unit is used to send data in parallel under the drive of the sending clock, sending bit 0 to bit 3 on the rising edge of the clock, sending bit 4 to bit 7 on the falling edge, and completing the data sending of one byte per clock cycle;

The error check unit is used to accumulate the eight-bit parallel data to be sent every sixteen consecutive clock cycles, and take the low eight bits of the accumulated sum as the checksum byte. The checksum clearing signal is sent in seven clock cycles, and a null byte is sent in the eighteenth clock; the data frame video signal sent by the data sending unit includes: data frame video signal, checksum byte, and null byte.

The video receiving module includes: a data receiving unit, a receiving error checking unit;

The data receiving unit is used to receive data in parallel at the same frequency as the sending clock.

The receiving error checking unit is used to output the eight-bit parallel data of each sixteen consecutive clock cycles as the received data, and at the same time accumulate and sum the data of each sixteen consecutive clock cycles to obtain the local calculation checksum, and the local calculation The checksum of the checksum is compared with the received 8-bit data of the seventeenth clock cycle. When the comparison results are the same, the currently received data is correct; otherwise, the data is incorrectly reported to the upper module. This ensures the accuracy and precision of the video image transmission of the transformer room and power distribution room, and prevents the influence of external signals on the video image transmission of the transformer room and power distribution room.

In this embodiment, the monitoring center 3 includes: an operation report generation module and a peak and valley statistics module;

The operation report generation module is used to automatically generate the operation duty record report, shift record report, equipment account, relay protection value table, equipment maintenance record table, load day, month and year report;

The peak and valley statistics module is used to generate peak and valley level electric energy statistics by hour, day, month, and year, and perform time-of-use billing statistics for electric energy according to peak, valley, and normal periods.

In order to further protect and monitor important equipment in the power supply system, in this embodiment, the on-site monitoring subsystem 1 includes: a transformer high-voltage side current detection module, a transformer medium-voltage side current detection module, and a current filter module;

The transformer high-voltage side current detection module is used to detect the three-phase current on the high-voltage side of the transformer and the zero-sequence current on the high-voltage side;

The current detection module on the medium-voltage side of the transformer is used to detect the three-phase current on the medium-voltage side of the transformer and the zero-sequence current on the medium-voltage side;

The current filter module filters the collected current;

The monitoring center includes: transformer zero-sequence current calculation module, transformer zero-sequence differential judgment module, transformer zero-sequence differential action module, zero-sequence voltage blocking module;

The zero-sequence voltage blocking module is used to detect the zero-sequence voltage when a ground fault occurs in the transformer;

When the zero-sequence current is self-generated by the three-phase current, if TA is disconnected, a "false" self-generated zero-sequence current will appear, which may cause the zero-sequence overcurrent element to malfunction, so the protection can be selected to block the zero-sequence voltage. When a ground fault occurs in the transformer, in addition to generating zero-sequence current, zero-sequence voltage also occurs. However, when TA is disconnected, although the three-phase current can filter out the zero-sequence current by itself, no zero-sequence voltage is generated. Therefore, zero-sequence voltage blocking can prevent malfunction caused by TA disconnection.

The transformer zero-sequence current calculation module is used to obtain the three-phase current on the high-voltage side of the transformer and the three-phase current on the medium-voltage side of the transformer, through I _op.0 =K ₁ *I _0G +K ₂ *I _0H , where K ₁ is 1 ～1.2, K ₂ takes 1.1～1.3 to get the zero-sequence current on both sides of the transformer; I _0G is the zero-sequence current on the high-voltage side, I _0H is the zero-sequence current on the medium-voltage side, and I _op.0 is the reference zero-sequence current on the high-voltage side;

The transformer zero-sequence differential determination module is used to determine whether the zero-sequence differential protection condition is satisfied. When I _op is greater than I _op.0 and I _op is greater than (0.6～0.9)*I _zd , the zero-sequence voltage blocking module detects zero-sequence differential protection. When the sequence voltage is low, the transformer zero-sequence differential action module starts the transformer zero-sequence protection;

I _op is the differential current of zero-sequence differential protection;

I _zd is the braking current of differential protection.

Among them, the monitoring center includes: transformer braking current calculation module;

The transformer braking current calculation module is used to obtain the three-phase current on the high-voltage side of the transformer and the three-phase current on the medium-voltage side of the transformer, through I _zd =K ₃ *I _G —K ₄ *I _H , where K ₃ is 0.7 to 1.3 , K ₄ takes 0.6~1.2 to get the braking current of differential protection;

I _G ＝max{│I _AG │,│I _BG │,│I _CG │},

Among them, I _AG , I _BG , and I _CG are the three-phase currents on the high-voltage side;

I _D =max{│I _AH │,│I _BH │,│I _CH │},

in

I _AG , I _BG , and I _CG are the three-phase currents at the high voltage side;

I _AH , I _BH , and I _CH are three-phase currents on the medium voltage side.

The power supply and distribution monitoring system has zero-sequence current protection, which can improve the sensitivity of the transformer's internal short circuit, avoid the lack of sensitivity of the traditional longitudinal differential protection in reflecting the ground fault and various problems caused by the excitation inrush current to the longitudinal differential protection application, and solve the original There is a problem of zero-sequence protection refusal to move. The zero-sequence protection is not affected by the operation mode of the transformer. The general braking current selection method is applicable to both the two-winding transformer and the autotransformer. Avoid misoperation of out-of-area phase-to-phase fault protection, improve the reliability of protection,

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the differences from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

The above description of the disclosed embodiments enables those skilled in the art to realize or use the utility model. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims (9)

1. A power supply and distribution monitoring system, characterized in that it comprises: an on-site monitoring subsystem, a communication network and a monitoring center; The on-site monitoring subsystem is used to collect analog quantities of on-site transformer equipment and power distribution equipment compatible with the transformer equipment, including: current, voltage, active power, reactive power, coil temperature, oil temperature on each side of the transformer ; Current, active power, reactive power of the power supply line; voltage and frequency of the bus bar; current of the section/bus coupler; three-phase voltage, three-phase current, zero-sequence voltage, zero-sequence current of the power supply line, and field equipment The switching value includes: high voltage circuit breaker position, isolating switch, grounding knife switch position, 380V circuit breaker switch position, DC main circuit switch position, protection action total signal; substation accident total signal, local/remote transfer switch position , circuit breaker operating mechanism abnormal signal, control circuit disconnection signal, protection alarm signal, protection device fault signal, power supply equipment abnormal signal, automatic device abnormal signal, DC system abnormal signal, fire alarm device fault signal, the on-site monitoring The subsystem transmits the collected data above to the monitoring center through the communication network; The communication network is used to transmit the on-site data collected by the on-site monitoring layer to the monitoring center; The monitoring center receives and stores, counts, analyzes and processes the collected data information, and issues control instructions through the communication network; The on-site monitoring subsystem includes: a transformer high-voltage side current detection module, a transformer medium-voltage side current detection module, and a current filter module; The transformer high-voltage side current detection module is used to detect the three-phase current on the high-voltage side of the transformer and the zero-sequence current on the high-voltage side; The transformer medium-voltage side current detection module is used to detect the three-phase current of the transformer medium-voltage side and the zero-sequence current of the medium-voltage side; The current filtering module filters the collected current; The monitoring center includes: a transformer zero-sequence current calculation module, a transformer zero-sequence differential judgment module, a transformer zero-sequence differential action module, and a zero-sequence voltage blocking module; The zero-sequence voltage blocking module is used to detect the zero-sequence voltage when a ground fault occurs in the transformer; The transformer zero-sequence current calculation module is used for obtaining the three-phase current on the high-voltage side of the transformer and the three-phase current on the medium-voltage side of the transformer, through I _op.0 =K ₁ *I _0G +K ₂ *I _0H , wherein, K ₁ Take 1~ _1.2 , K2 take 1.1~1.3, get the zero-sequence current on both sides of the transformer; I _0G is the zero-sequence current on the high-voltage side, I _0H is the zero-sequence current on the medium-voltage side, and I _op.0 is the reference zero-sequence on the high-voltage side current; The transformer zero-sequence differential determination module is used to determine whether the zero-sequence differential protection condition is met, and when I _op is greater than I _op.0 and I _op is greater than (0.6-0.9)*I _zd , the zero-sequence voltage is blocked When the module detects the zero-sequence voltage, the transformer zero-sequence differential action module starts the transformer zero-sequence protection; I _op is the differential current of zero-sequence differential protection; I _zd is the braking current of differential protection ratio. 2. The power supply and distribution monitoring system according to claim 1, characterized in that, The monitoring center includes: a transformer braking current calculation module; The transformer braking current calculation module is used to obtain the three-phase current on the high-voltage side of the transformer and the three-phase current on the medium-voltage side of the transformer, through I _zd =K ₃ *I _G -K ₄ *I _H , where K ₃ is 0.7 ～1.3, K ₄ takes 0.6～1.2 to get the differential protection ratio braking current; I _G ＝max{│I _AG │,│I _BG │,│I _CG │}, Among them, I _AG , I _BG , and I _CG are the three-phase currents on the high-voltage side; I _D =max{│I _AH │,│I _BH │,│I _CH │}, in I _AG , I _BG , and I _CG are the three-phase currents at the high voltage side; I _AH , I _BH , and I _CH are three-phase currents on the medium voltage side. 3. The power supply and distribution monitoring system according to claim 1, characterized in that, The monitoring center includes: an IP encoding module; The IP encoding module is used to set the unique IP address of each monitoring unit of the on-site monitoring subsystem; The on-site monitoring subsystem includes: a humidity sensor, a transformer monitoring unit, The humidity sensor is used for real-time monitoring of the humidity in the substation room and power distribution room; The transformer monitoring unit is used for real-time monitoring of the running state of the transformer in the substation. 4. The power supply and distribution monitoring system according to claim 3, characterized in that, The transformer monitoring unit adopts a camera device; The camera device includes: a video acquisition module, a video decomposition module, a heat sensing module, and a video transmission module; The video acquisition module is used to take images of the transformer room and the power distribution room; The heat sensing module is used to sense the temperature of the transformer in the transformer room and the temperature of the power distribution cabinet in the power distribution room; The video decomposition module is used to decompose the ingested video picture in a frame-by-frame manner; The video transmission module is used to transmit each frame of image and the thermal information sensed by the thermal sensing module to the monitoring center; The monitoring center includes: a standard image setting module, an image comparison module, an image synthesis unit, a video receiving module, and a temperature alarm module; The standard image setting module is used to set the standard images of the transformer room and the power distribution room; The video receiving module is used to receive images transmitted by the video transmission module and heat information sensed by the heat sensing module; The image synthesis unit is used to combine each frame of images received to form a complete image of the transformer room and power distribution room; The image comparison module is used to compare the received images of the transformer room and the power distribution room with the standard images of the transformer room and the power distribution room respectively. When there is a difference between the received image information and the standard image information, Issue a prompt message; The temperature alarm module is used for sending out an alarm message when the heat information sensed by the heat sensing module exceeds a set temperature. 5. The power supply and distribution monitoring system according to claim 4, characterized in that, The camera includes: a face recognition module; The monitoring center includes: a human body identification module; The face recognition module is used to recognize the face of the person entering the transformer room or power distribution room, and transmits it to the monitoring center through the video transmission module; The human body identification module is used to recognize the person entering the transformer room or power distribution room according to the received facial recognition information and combined with the thermal sensor module to sense the temperature information of the human body. 6. The power supply and distribution monitoring system according to claim 5, characterized in that, The monitoring center includes: a time setting module, a human body judgment and alarm module; The time setting module is used to set the running time period, non-running time period and maintenance time period of the power supply system; The human body judgment alarm module is used to identify persons entering the transformer room or power distribution room by the human body identification module during the running time period of the power supply system, and the human body judgment alarm module sends out a safety alarm; during the non-running time period of the power supply system , the human body identification module recognizes that a person enters the transformer room or power distribution room, and the human body identification alarm module sends out an anti-theft alarm; during the power supply system maintenance time period, the maintenance personnel are monitored for maintenance operations. 7. The power supply and distribution monitoring system according to claim 4, characterized in that, The video transmission module includes: a data sending unit, a sending clock, and an error checking unit; The data sending unit is used to send data in parallel under the drive of the sending clock, sending bit 0 to bit 3 on the rising edge of the clock, sending bit 4 to bit 7 on the falling edge, and completing the data sending of one byte per clock cycle ; The error checking unit is used for accumulating the eight-bit parallel data to be sent every sixteen consecutive clock cycles, and taking the low eight bits of the accumulated sum as a checksum byte, and each passing through sixteen consecutive clock cycles The seventeenth clock cycle sends a verification accumulation clearing signal, and sends a null byte at the eighteenth clock; the data frame video signal sent by the data sending unit includes: data frame video signal, checksum byte, Null bytes. 8. The power supply and distribution monitoring system according to claim 7, characterized in that, The video receiving module includes: a data receiving unit, a receiving error checking unit; The data receiving unit is used to receive data in parallel at the same frequency as the sending clock; The receiving error checking unit is used to output the eight-bit parallel data of each sixteen consecutive clock cycles as the received data, and at the same time accumulate and sum the data of each sixteen consecutive clock cycles to obtain a local calculation checksum, The locally calculated checksum is compared with the received 8-bit data of the seventeenth clock cycle. If the comparison result is the same, the currently received data is correct; otherwise, the data is wrongly reported to the upper module. 9. The power supply and distribution monitoring system according to claim 1, characterized in that, The monitoring center includes: an operation report generation module and a peak and valley statistics module; The operation report generation module is used to automatically generate the operation duty record report, the shift record report, the equipment account, the relay protection fixed value table, the equipment maintenance record table, the load day, month and year report; The peak-valley statistical module is used to generate peak-valley level electric energy statistics by hour, day, month, and year, and perform time-of-use charging statistics for electric energy according to peak, valley, and normal periods.