CN107561341A - Arrester resistance current on-line monitoring method based on wireless synchronization Sampling techniques - Google Patents

Abstract

The invention belongs to the technical field of online monitoring of lightning arresters, and in particular relates to an online monitoring method for resistive current of lightning arresters based on wireless synchronous sampling technology, in particular to an online monitoring method for detecting the electrical performance of metal oxide lightning arresters. The invention includes a current signal acquisition device, a voltage signal acquisition device, a handheld device terminal, a data acquisition device, an RS485 bus and a comprehensive state monitoring unit. The hand-held device terminal of the present invention has its own operation keyboard, display screen and communication interface, which is convenient for test personnel to operate, observe and upload data and waveforms. It can realize the display and query functions of stored data, and complies with the "Station Interface Specification of Intelligent Substation Status Monitoring System". Improve the anti-interference ability of each device, have a reliable surge protection circuit, design the overvoltage protection circuit for the voltage and current signal acquisition and measurement circuit, power supply circuit, communication circuit and other interfaces, effectively improve the reliability of each device .

Description

On-line monitoring method of arrester resistive current based on wireless synchronous sampling technology

technical field

The invention belongs to the technical field of online monitoring of lightning arresters, and in particular relates to an online monitoring method for resistive current of lightning arresters based on wireless synchronous sampling technology, in particular to an online monitoring method for detecting the electrical performance of metal oxide lightning arresters.

Background technique

Surge arresters are an important overvoltage protection device and a powerful guarantee for the safe operation of power systems. Among them, metal oxide arresters are widely used in power grids due to their excellent nonlinearity and large flow capacity. If the non-gap metal oxide arrester fails, the problem will be more serious than the valve arrester with series gap, so the work of measuring the resistive current of the non-gap metal oxide arrester in operation has been paid more and more attention.

At present, all lightning arresters in substations are equipped with counting meters, and inspection personnel usually observe the leakage current value and the number of operations displayed by the counting meters to preliminarily judge the operating status of the arresters. With the vigorous development of the smart grid, on-site lightning arresters are equipped with online monitoring devices, and the secondary signal of the PT voltage transformer is introduced into the device. As the online monitoring device runs longer in the outdoor environment, the interior is prone to moisture or damage. It is very easy to cause secondary faults of PT and lead to accidents. Instead of using the voltage reference method, the on-line monitoring device can only measure the trend of resistive current change, and cannot obtain its true value.

According to the routine test requirements, the operation status of the arrester needs to be measured with a portable resistive current measuring instrument. The operation of the resistive current test instrument usually requires 2-3 people to complete the test of the whole station, and the test clip needs to be carried out by the tester. In this way, not only the human body has radiation hazards under high field strength, but also it is easy to cause the danger of human body being in contact with high voltage. Whether it is a traditional substation or a smart substation, it is necessary to use a resistive current tester to detect the operating status of the arrester in routine tests. The existing test system cannot reduce the test workload brought by the arrester resistive current live detection to the inspectors. At the same time, the PT may be operated multiple times, the work efficiency is low, and there are many major safety hazards.

Therefore, it is very necessary to conduct research on the online monitoring method of arrester resistive current based on wireless synchronous sampling technology.

Contents of the invention

Aiming at the problems existing in the above-mentioned prior art, the present invention provides an online monitoring method for arrester resistive current based on wireless synchronous sampling technology. Resistive current measurement workload, and can detect the aging or damp problems of the arrester in time, monitor the operating parameters of the arrester in real time, and prevent the occurrence of faults.

In order to realize the above-mentioned purpose of the invention, the technical scheme that the present invention solves its technical problem adopts is:

The online monitoring method of arrester resistive current based on wireless synchronous sampling technology, including current signal acquisition device, voltage signal acquisition device, handheld device terminal, data acquisition device, RS485 bus and comprehensive state monitoring unit; by installing the current signal acquisition device on the arrester At the end of the main body, the leakage current value of the arrester is obtained, and the current signal acquisition device collects, calculates, processes, stores and displays the current signal on the spot, and communicates with the data acquisition device through 2.4G wireless communication technology; the voltage signal acquisition device is installed On the secondary side of the PT, the working voltage signal of the lightning arrester of each phase is obtained, and the voltage signal acquisition device collects and calculates the voltage signal, and communicates with the data acquisition device through 2.4G wireless communication technology; after the data acquisition device obtains the data, it passes RS485 The bus is connected with the comprehensive state monitoring unit for data communication, and the data acquisition device can also perform data interaction with the handheld device terminal through 433MHz wireless communication at the same time.

The current signal acquisition device is installed at the end of the arrester body, and is used for online monitoring of the arrester's full current, full current fundamental wave phase, fundamental wave frequency, number of actions, and action occurrence time. Check the operating status of the arrester on site. The device has a built-in 2.4G wireless communication module, which can receive instructions and send data through 2.4G wireless communication.

The voltage signal acquisition device is installed on the secondary side of the PT to monitor the secondary side voltage of the PT and parameters such as voltage fundamental wave phase and frequency. The device has a built-in 2.4G wireless communication module to receive instructions and send data through 2.4G wireless communication .

The 2.4G wireless communication module includes a 2.4G wireless module and a 2.4G antenna, and is a resistive current-related data interaction mode between the data acquisition device and the current signal acquisition device and the voltage signal acquisition device.

The data acquisition device is installed in the substation, and sends a wireless synchronous acquisition signal to the current signal acquisition device and the voltage signal acquisition device through a built-in 2.4G wireless communication module, and receives the acquisition data sent by the current signal acquisition device and the voltage signal acquisition device, That is to realize the synchronous acquisition of the PT secondary side voltage and the full current of the three-phase arrester; through wireless communication, the relevant monitoring data of the current signal acquisition device and the voltage signal acquisition device are collected, and then the resistive current of the three-phase arrester is calculated.

The data acquisition device has a remote communication function and adopts the MODBUS-RTU protocol; the data acquisition device has a built-in 433MHz wireless communication module to realize remote wireless communication with the handheld terminal equipment.

The 433MHz wireless communication module includes a 433MHz wireless module and a 433MHz antenna, which is a related data interaction mode between the data acquisition device and the handheld device terminal; the data acquisition device is connected with the comprehensive status monitoring unit in the station through the RS485 bus, and the acquisition calculation is sent through the protocol The data.

The comprehensive status monitoring unit and the handheld device terminal display monitoring data, storage data and configuration parameters in real time; wherein, the standard RS485 bus communication interface, communication parameters can be flexibly configured, and facilitate communication with the comprehensive status monitoring unit, which conforms to the "Smart Substation Status Monitoring System station interface specification"; when the full current value and resistive current value of the arrester monitored by the data acquisition device exceed the user's set value, an alarm signal will be output to detect the aging or damp problems of the arrester in time to prevent the occurrence of failure; the comprehensive The state monitoring unit is connected with the data acquisition device based on wireless data communication technology through the standard RS485 bus communication interface to obtain the online monitoring data of the resistive current of the arrester, and display the full current, resistive current, alarm information, number of actions and action time of the arrester through the software interface and other related parameters.

The handheld device terminal realizes remote acquisition of monitoring data of the data acquisition device, remote setting of relevant parameters of the data acquisition device, voltage signal acquisition device and current signal acquisition device, and realizes hand-held inspection, real-time viewing and setting of online monitoring data.

The online monitoring method of arrester resistive current based on wireless synchronous sampling technology, the specific operation steps are as follows:

(1) Use the current signal acquisition device to collect the current signal of the arrester, and the current signal acquisition device realizes data interaction with the data acquisition device and synchronous sampling of voltage and current through 2.4G wireless synchronization technology;

(2) The voltage signal acquisition device is installed on the secondary side of the PT to collect voltage signals; the voltage signal acquisition device realizes data interaction with the data acquisition device and synchronous sampling of voltage and current through 2.4G wireless synchronization technology;

(3) The data acquisition device is connected with the comprehensive status monitoring unit at the station according to the "Interface Specifications of the Intelligent Substation Status Monitoring System"; the data is uploaded through the MODBUS-RTU communication protocol, and the computer communicates, measures, alarms, and Calibration parameters are configured;

(4) The data acquisition device utilizes the high communication rate of 2.4G wireless communication technology to realize synchronous sampling of the voltage and current of the voltage and current signal acquisition device; the preliminary calculation result data of the voltage signal acquisition device and the current signal acquisition device pass through 2.4G wireless communication uploaded to the data acquisition device;

(5) The data acquisition device calculates the resistive current after obtaining the calculation results and sampling time of the voltage signal acquisition device and the current signal acquisition device, and saves the data to the FLASH memory of the device for subsequent analysis;

(6) The data acquisition device uploads the real-time data or historical data obtained in step 5 to the station-side comprehensive status monitoring unit through the RS485 bus, and the station-side comprehensive status monitoring unit can configure various related parameters for the data acquisition device through the protocol;

(7) The handheld device terminal realizes data communication with the data acquisition device through 433MHz wireless communication technology, and obtains the real-time data or historical data obtained in step 5. The handheld device terminal configures various relevant parameters of the data acquisition device through the protocol.

Advantage of the present invention and beneficial effect are:

Through the implementation of the technical solution of the invention, accurate and stable real-time monitoring of the resistive current of the arrester can be truly realized. The design method of the present invention has the following innovations:

1. Innovation in monitoring methods:

(1) All-wireless communication design to realize the wireless synchronous measurement of the resistive current of the three-phase arrester. The voltage and current signals are completely isolated from the data acquisition device, eliminating the interference between the measurement circuits of each phase, making the measurement data effective and reliable, and easy to install;

(2) Use software anti-interference methods such as harmonic analysis method and digital filter algorithm to make the measurement results accurate and stable; and can overcome the influence of phase-to-phase interference, and correctly measure the resistive current of the side-phase arrester;

(3) In view of the characteristics of the large leakage current measurement range of UHV large-capacity zinc oxide arresters, the current signal acquisition device has the functions of intelligent current detection and automatic range switching to meet the online monitoring test requirements of zinc oxide arresters of various voltage levels.

2. Innovation in structural design:

(1) The shell of the current signal acquisition device is made of cast aluminum, which is divided into upper and lower parts. The upper shell has a window and is sealed by tempered glass. The surface of the tempered glass is mounted with a 2.4GHz communication antenna. The ammeter and the counting meter are installed on the upper shell. body, which can be displayed from the window. The top of the lower shell is equipped with insulating pillars, and the leakage current of the lightning arrester is introduced to the circuit board through the insulating pillars; the bottom of the lower shell is also provided with two mounting holes and two aviation sockets for wiring.

(2) The voltage signal acquisition device adopts a square metal shell with a built-in voltage division measurement unit and an external 2.4GHz communication antenna. There are two aviation sockets for wiring on the upper part and the bottom respectively. The upper aerial socket is used to connect with the PT secondary side voltage signal, and the lower aerial socket is used to connect with the power supply, using a two-core shielded cable to connect.

(3) The data acquisition device adopts a square metal shell with a built-in data processing unit and two external communication antennas of 2.4GHz and 433MHz. There is an aviation socket for wiring at the bottom, which is used to connect with the power supply and the comprehensive state monitoring unit, and is connected with a four-core shielded cable.

3. The handheld device terminal comes with an operation keyboard, a large-screen LCD display and an RJ45 communication interface, which is convenient for the test personnel to operate, observe and upload data and waveforms.

4. The data acquisition device has the test data storage function, which can save the test data in the device memory, and the stored data will not be lost when the power is turned off, and can continuously save the test data for more than one year. Provide a basis for analyzing the operating state of the arrester.

5. The data acquisition device can be connected with the comprehensive status monitoring unit in the station and communicate with the handheld terminal equipment at the same time. The data acquisition device is connected to the comprehensive status monitoring unit in the station through the RS485 bus, and the collected and calculated data is sent through the MODBUS-RTU communication, and the stored data display and query functions are realized by the dedicated upper computer software. Comply with the "Station Interface Specifications of Intelligent Substation Condition Monitoring System".

6. Anti-electromagnetic interference and surge protection circuit design. Since the current signal acquisition device, voltage signal acquisition device and data acquisition device are all in a high voltage and strong magnetic field environment, the electromagnetic interference generated by the electronic equipment may easily lead to inaccurate monitoring data and abnormal operation. For this reason, special measures are taken from hardware and software to improve the anti-interference ability of each device. Each device is designed with a reliable surge protection circuit, and the overvoltage protection circuit is designed for the voltage and current signal acquisition and measurement circuit, power supply circuit, communication circuit and other interfaces, which effectively improves the reliability of each device.

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments, but is not limited by the embodiments.

Description of drawings

Fig. 1 is a schematic diagram of the working principle of the present invention.

In the figure: current signal acquisition device 1, voltage signal acquisition device 2, handheld device terminal 3, data acquisition device 4, RS485 bus 5, and comprehensive status monitoring unit 6.

detailed description

The invention is an online monitoring method for the resistive current of the arrester based on the wireless synchronous sampling technology, which can be used for the online monitoring of the resistive current of the arrester for the whole station. As shown in Figure 1, Figure 1 is a schematic diagram of the working principle of the present invention. The present invention includes a current signal acquisition device 1, a voltage signal acquisition device 2, a handheld device terminal 3, a data acquisition device 4, an RS485 bus 5 and a comprehensive state monitoring unit 6. By installing the current signal acquisition device 1 on the end of the arrester body, the leakage current value of the arrester is obtained. The current signal acquisition device 1 collects, calculates, processes, stores and displays the current signal, and communicates with the data through 2.4G wireless communication technology. The acquisition device 4 communicates; the voltage signal acquisition device 2 is installed on the secondary side of the PT to obtain the working voltage signal of the lightning arrester of each phase, and the voltage signal acquisition device 2 collects and calculates the voltage signal. Through 2.4G wireless communication technology and data The acquisition device 4 communicates; after the data acquisition device 4 obtains the data, it is connected to the comprehensive status monitoring unit 6 through the RS485 bus 5 for data communication, and the data acquisition device 4 can also perform data interaction with the handheld device terminal 3 through 433MHz wireless communication at the same time.

Among them, the current signal acquisition device 1 is installed at the end of the arrester body, and is used for online monitoring of the arrester's full current, full current fundamental wave phase, fundamental wave frequency, number of actions, and action occurrence time. It also has a local mechanical ammeter and counter display, It is convenient to check the operation status of the arrester on site. The device has a built-in 2.4G wireless communication module, which can receive instructions and send data through 2.4G wireless communication.

The voltage signal acquisition device is installed on the secondary side of the PT to monitor the secondary side voltage of the PT and parameters such as the phase and frequency of the voltage fundamental wave. The device has a built-in 2.4G wireless communication module to receive instructions and send data through 2.4G wireless communication. The 2.4G wireless communication module includes a 2.4G wireless module and a 2.4G antenna, which is a resistive current-related data interaction mode between the data acquisition device 4, the current signal acquisition device 1 and the voltage signal acquisition device 2.

The data acquisition device is installed in an open place in the substation. Through the built-in 2.4G wireless communication module, it sends wireless synchronous acquisition signals to the current signal acquisition device 1 and the voltage signal acquisition device 2, and receives the data collected by the current signal acquisition device and the voltage signal acquisition device. Data, that is, to realize the synchronous acquisition of the PT secondary side voltage and the full current of the three-phase arrester. Through wireless communication, the relevant monitoring data of the current signal acquisition device and the voltage signal acquisition device are collected, and then the resistive current of the three-phase arrester is calculated.

The data acquisition device also has remote communication function and adopts MODBUS-RTU protocol. The data acquisition device has a built-in 433MHz wireless communication module, so as to realize remote wireless communication with handheld terminal equipment. Described 433MHz wireless communication module comprises 433MHz wireless module and 433MHz antenna, is the relevant data interaction mode between data collection device 4 and handheld device terminal 3. The data acquisition device is connected to the comprehensive status monitoring unit in the station through the RS485 bus, and the collected and calculated data are sent through the protocol. The comprehensive status monitoring unit 6 and the handheld device terminal 3 can display monitoring data, storage data and configuration parameters in real time. Among them, the standard RS485 bus communication interface, the communication parameters can be flexibly configured, and it is convenient to communicate with the comprehensive status monitoring unit, which is in line with the "Station Interface Specification of Intelligent Substation Status Monitoring System". When the full current value and resistive current value of the arrester monitored by the data acquisition device exceed the user's set value, an alarm signal will be output to detect the aging or damp problems of the arrester in time to prevent the occurrence of faults.

The invention integrates the industry's mainstream PT reference voltage method, AC 220V reference voltage method, phase angle method and third harmonic method, and is an online monitoring method for arresters based on four working principles; it supports single-phase or three-phase simultaneous measurement, and can accurately measure the arrester Parameters such as full current, resistive current, number of actions, action time, operating voltage of the phase arrester under test, voltage harmonic content, voltage fundamental wave and total current fundamental wave, etc. The accuracy and work efficiency of the online monitoring of the operating state of the arrester can be significantly improved.

The present invention also has the functions of real-time monitoring of arrester resistive current data and over-limit alarming. The alarm threshold can be defined by the user. The alarm signal enables the staff to take timely measures to avoid failures and ensure the stable operation of the power system.

The comprehensive status monitoring unit conforming to the "Station Interface Specification of Intelligent Substation Status Monitoring System" is connected with the data acquisition device based on wireless data communication technology through the standard RS485 bus communication interface to obtain the online monitoring data of the resistive current of the arrester, and display the full status of the arrester through the software interface. Related parameters such as current, resistive current, alarm information, number of actions, and action time are convenient for viewing the operating status of the arrester.

Through the handheld device terminal 3, the monitoring data of the data acquisition device 4 is obtained remotely, and the relevant parameters of the data acquisition device 4, the voltage signal acquisition device 2 and the current signal acquisition device 1 are remotely set, so as to realize the hand-held inspection, real-time viewing and monitoring of online monitoring data. set up.

The present invention is an online monitoring method for the resistive current of an arrester based on wireless synchronous sampling technology. The specific operation steps are as follows:

1. Use the current signal acquisition device to collect the current signal of the arrester. The current signal acquisition device realizes data interaction with the data acquisition device and synchronous sampling of voltage and current through 2.4G wireless synchronization technology.

2. The voltage signal acquisition device is installed on the secondary side of the PT to collect voltage signals; the voltage signal acquisition device realizes data interaction with the data acquisition device and synchronous sampling of voltage and current through 2.4G wireless communication technology.

3. The data acquisition device is connected with the comprehensive status monitoring unit of the station according to the "Station Interface Specification of the Intelligent Substation Status Monitoring System"; the data is uploaded through the MODBUS-RTU communication protocol, and the computer can use the serial port debugging assistant and other serial tools to control the data acquisition device. Configure parameters such as communication, measurement, alarm, and calibration.

4. The data acquisition device uses the high communication rate of 2.4G wireless communication technology to realize the synchronous sampling of voltage and current of the voltage and current signal acquisition device; the preliminary calculation result data of the voltage signal acquisition device and current signal acquisition device are uploaded through 2.4G wireless communication on the data acquisition device.

5. The data acquisition device calculates the resistive current after obtaining the calculation results and sampling time of the voltage signal acquisition device and the current signal acquisition device, and saves the data to the FLASH memory of the device for subsequent analysis.

6. The data acquisition device uploads the real-time data or historical data obtained in step 5 to the station-end comprehensive status monitoring unit through the RS485 bus, and the station-side comprehensive status monitoring unit communicates with the data acquisition device 4 to configure various related parameters.

7. The handheld device terminal realizes data communication with the data acquisition device through 433MHz wireless communication technology, obtains the real-time data or historical data obtained in step 5, and configures various relevant parameters of the data acquisition device through the protocol.

Claims (10)

1. The online monitoring method of arrester resistive current based on wireless synchronous sampling technology, which is characterized by: including current signal acquisition device (1), voltage signal acquisition device (2), handheld device terminal (3), data acquisition device (4) , RS485 bus (5) and integrated state monitoring unit (6); by installing the current signal acquisition device (1) on the end of the arrester body, the leakage current value of the arrester is obtained, and the current signal acquisition device (1) collects the current signal , calculation and processing, and on-site storage and display, and communicate with the data acquisition device (4) through 2.4G wireless communication technology; install the voltage signal acquisition device (2) on the secondary side of the PT to obtain the working voltage signals of the arresters of each phase, The voltage signal acquisition device (2) collects and calculates the voltage signal, and communicates with the data acquisition device (4) through 2.4G wireless communication technology; after the data acquisition device (4) obtains the data, it communicates with the The comprehensive status monitoring unit (6) is connected to perform data communication, and the data acquisition device (4) can also perform data interaction with the handheld device terminal (3) through 433MHz wireless communication at the same time. 2. The online monitoring method for arrester resistive current based on wireless synchronous sampling technology according to claim 1, characterized in that: the current signal acquisition device (1) is installed at the end of the arrester body for online monitoring of the arrester's full current, Parameters such as full current fundamental wave phase, fundamental wave frequency, number of actions, and action occurrence time, etc., also have local mechanical ammeter and counter display, which is convenient for viewing the operating status of the arrester on site. The device has a built-in 2.4G wireless communication module, through 2.4G wireless communication to receive commands and send data. 3. The online monitoring method of arrester resistive current based on wireless synchronous sampling technology according to claim 1, characterized in that: the voltage signal acquisition device (2) is installed on the secondary side of the PT for monitoring the secondary side of the PT Voltage and voltage fundamental wave phase, frequency and other parameters, the device has a built-in 2.4G wireless communication module, and receives instructions and sends data through 2.4G wireless communication. 4. the lightning arrester resistive current online monitoring method based on wireless synchronous sampling technology according to claim 3, is characterized in that: described 2.4G wireless communication module comprises 2.4G wireless module and 2.4G antenna, is data collection device (4 ) and the resistive current-related data interaction method between the current signal acquisition device (1) and the voltage signal acquisition device (2). 5. The online monitoring method of arrester resistive current based on wireless synchronous sampling technology according to claim 1, characterized in that: the data acquisition device (4) is installed in the substation, through the built-in 2.4G wireless communication module, to the current The signal acquisition device (1) and the voltage signal acquisition device (2) send out wireless synchronous acquisition signals, and receive the acquisition data sent by the current signal acquisition device (1) and the voltage signal acquisition device (2), that is, to realize the PT secondary side voltage and Synchronous acquisition of the full current of the three-phase arrester; through wireless communication, the relevant monitoring data of the current signal acquisition device (1) and the voltage signal acquisition device (2) are collected, and then the resistive current of the three-phase arrester is calculated. 6. The online monitoring method for arrester resistive current based on wireless synchronous sampling technology according to claim 1, characterized in that: the data acquisition device (4) has a remote communication function and adopts the MODBUS-RTU protocol; the data acquisition device has a built-in 433MHz wireless communication module realizes remote wireless communication with handheld terminal equipment. 7. The online monitoring method for arrester resistive current based on wireless synchronous sampling technology according to claim 1, characterized in that: the 433MHz wireless communication module includes a 433MHz wireless module and a 433MHz antenna, which is a data acquisition device (4) and The relevant data interaction mode between handheld device terminals (3); the data acquisition device (4) is connected to the comprehensive status monitoring unit (6) in the station through the RS485 bus (5), and the collected and calculated data is sent through the protocol. 8. The online monitoring method of arrester resistive current based on wireless synchronous sampling technology according to claim 1, characterized in that: the comprehensive state monitoring unit (6) and the handheld device terminal (3) display monitoring data and store data in real time and configuration parameters; among them, the standard RS485 bus (5) communication interface, the communication parameters can be flexibly configured to facilitate communication with the integrated status monitoring unit (6), which conforms to the "Station Interface Specification for Smart Substation Status Monitoring System"; when the data acquisition device ( 4) When the monitored full current value and resistive current value of the arrester exceed the user's set value, an alarm signal will be output to detect the aging or damp problems of the arrester in time to prevent the occurrence of faults; the comprehensive state monitoring unit (6) and based on The data acquisition device (4) of wireless data communication technology is connected through the standard RS485 bus (5) communication interface to obtain the online monitoring data of the resistive current of the arrester, and display the full current, resistive current, alarm information, number of actions and actions of the arrester through the software interface time and other related parameters. 9. the lightning arrester resistive current online monitoring method based on wireless synchronous sampling technology according to claim 1, is characterized in that: The handheld device terminal (3) realizes remote acquisition of monitoring data of the data acquisition device (4), remotely sets relevant parameters of the data acquisition device (4), voltage signal acquisition device (2) and current signal acquisition device (1), and realizes Hand-held inspection, real-time viewing and setting of online monitoring data. 10. the lightning arrester resistive current online monitoring method based on wireless synchronous sampling technology according to claim 1, is characterized in that: The specific operation steps are as follows: (1) Use the current signal acquisition device to collect the current signal of the arrester, and the current signal acquisition device realizes data interaction with the data acquisition device and synchronous sampling of voltage and current through 2.4G wireless synchronization technology; (2) The voltage signal acquisition device is installed on the secondary side of the PT to collect voltage signals; the voltage signal acquisition device realizes data interaction with the data acquisition device and synchronous sampling of voltage and current through 2.4G wireless synchronization technology; (3) The data acquisition device is connected with the comprehensive status monitoring unit at the station according to the "Interface Specifications of the Intelligent Substation Status Monitoring System"; the data is uploaded through the MODBUS-RTU communication protocol, and the computer communicates, measures, alarms, and Calibration parameters are configured; (4) The data acquisition device utilizes the high communication rate of 2.4G wireless communication technology to realize synchronous sampling of the voltage and current of the voltage and current signal acquisition device; the preliminary calculation result data of the voltage signal acquisition device and the current signal acquisition device pass through 2.4G wireless communication uploaded to the data acquisition device; (5) The data acquisition device calculates the resistive current after obtaining the calculation results and sampling time of the voltage signal acquisition device and the current signal acquisition device, and saves the data to the FLASH memory of the device for subsequent analysis; (6) The data acquisition device uploads the real-time data or historical data obtained in step 5 to the station-side comprehensive status monitoring unit through the RS485 bus, and the station-side comprehensive status monitoring unit can configure various related parameters for the data acquisition device through the protocol; (7) The handheld device terminal realizes data communication with the data acquisition device through 433MHz wireless communication technology, and obtains the real-time data or historical data obtained in step 5. The handheld device terminal configures various relevant parameters of the data acquisition device through the protocol.