CN116047156A - System and method for monitoring resistive current of wireless zinc oxide arrester - Google Patents

Abstract

The invention discloses a wireless zinc oxide arrester resistive current monitoring system which comprises a voltage transformer, a wireless voltage sensor, a wireless current sensor and a field data processing terminal, wherein the voltage transformer is connected to a bus of alternating current; the wireless voltage sensors are sleeved on wires connecting the voltage transformer with the ground wire, the number of the wireless current sensors is 3, and the wireless current sensors are respectively sleeved on wires connecting the phase A, the phase B and the phase C of the lightning arrester with the ground wire; the wireless current sensor and the wireless voltage sensor are connected with the field data processing terminal in a signal connection mode through wireless communication. The method realizes synchronous measurement of the resistive current of the zinc oxide arrester equipment of the transformer substation, and more accurately and effectively judges the operation safety state of the arrester; the monitoring data is uploaded in a wireless mode, so that the back-and-forth running meter reading of operators is reduced, and the working efficiency is greatly improved.

Description

Wireless zinc oxide arrester resistive current monitoring system and monitoring method

technical field

The invention relates to a resistive current monitoring system and a monitoring method of a wireless zinc oxide arrester, belonging to the technical field of arrester monitoring systems.

Background technique

In recent years, explosion accidents caused by valve aging and electrical performance deterioration of AC non-gap oxide surge arresters in substations have occurred from time to time, which has brought huge economic losses to the national economy and brought great harm to the safe operation of the power grid. serious threat. For this reason, experts and scholars in scientific research institutes and electric power departments have researched and developed a variety of instruments and devices for monitoring the insulation performance of arresters. The use of these instruments and devices has played a certain role in ensuring the safe operation of the power grid.

Zinc oxide surge arresters (MOA) have the advantages of large flow capacity, low residual voltage, fast response, long life, etc., can effectively protect power equipment, and are widely used in overvoltage protection of power systems. Since MOA has good non-linear resistance characteristics, there is no gap inside the zinc oxide arrester. It is precisely because there is no gap that the valve plate is subjected to the operating voltage of the power system for a long time during normal operation, as well as the influence of factors such as internal moisture or overheating, which will cause the deterioration of the non-linear resistance characteristics of the valve plate. The main manifestation of this deterioration is the increase of resistive current under normal voltage. The increase of resistive current causes the increase of calorific value, the rise of internal temperature of arrester, and the rise of temperature accelerates the aging of valve plate, forming a vicious cycle. Finally, the MOA is damaged due to overheating, which may cause the explosion of the arrester in severe cases, causing a large-scale power outage.

The leakage current of the zinc oxide arrester can be divided into two parts: the capacitive part and the resistive part. Under normal circumstances, the component of the resistive current in the full current is relatively small, so the increase of the resistive current has a small increase in the full current. The monitoring of the full current is not very sensitive to the change of the resistive current. The best way to monitor the non-linear resistance characteristics of the valve is to directly monitor the resistive current.

MOA resistive current live detection equipment is commonly used in the power grid, but there are many on-site wiring, the test layout is relatively cumbersome, and the MOA action during the measurement process will cause risks to personnel and equipment. Therefore, in recent years, there have been products using wireless sensors, but they cannot To solve the problem of synchronous measurement of voltage and current, the acquisition of current signals still requires the installation of current leads, which brings a large workload to field applications.

Contents of the invention

The technical problem to be solved by the present invention is to provide a wireless zinc oxide arrester resistive current monitoring system, which completely uses wireless means to monitor the resistive current, and can solve the problem of synchronous measurement of voltage and current, greatly reducing the workload of field use.

The technical solution adopted by the present invention is: a wireless zinc oxide arrester resistive current monitoring system, including a voltage transformer, a wireless voltage sensor, a wireless current sensor and a field data processing terminal, and one end of the A phase, B phase and C phase of the three-phase arrester They are respectively electrically connected to phase A, phase B and phase C of the alternating current, and the other end of the phase A, phase B and phase C of the three-phase arrester is grounded, and the voltage transformer is connected to the busbar of the alternating current; the wireless voltage sensor It is set on the wire connecting the voltage transformer and the ground wire, and the number of the wireless current sensors is set to 3, and they are respectively set on the wires connecting the A phase, B phase, and C phase of the arrester and the ground wire ; The wireless current sensor and the wireless voltage sensor are connected to the field data processing terminal through wireless communication.

Preferably, satellite signal receiving devices are installed on the wireless voltage sensor and the wireless current sensor.

Preferably, the wireless current sensor includes a signal acquisition module, a signal conditioning module, a processor, a data storage module, a control module and a power supply module,

The signal acquisition module is used to acquire current signals;

The signal conditioning module transmits the collected current signal to the processor after conditioning;

The processor is used to process the conditioned current signal, and the processor is connected to a CMA through a local area network signal, and the CMA is connected to the on-site data processing terminal signal through wireless communication;

The data storage module is used for storing the processed data;

The power module is used to provide power.

Preferably, an ADC high-speed acquisition chip is arranged between the signal conditioning module and the processor.

Preferably, the processor is an FPGA processor.

Preferably, the data storage module is a high-speed SRAM.

Preferably, the CMA is signal-connected with the on-site data processing terminal through WIFI communication.

Preferably, the control module sends the positions of the wireless current sensor and the wireless voltage sensor to the remote terminal through the GPS communication module. .

A method for monitoring a resistive current of a wireless zinc oxide arrester comprises the following steps:

S1, installing a wireless current sensor between the lightning arrester and the ground wire, installing a wireless voltage sensor between the voltage transformer and the ground wire, and installing a field data processing terminal on site, the wireless current sensor and the wireless voltage sensor are both compatible with the The on-site data processing terminal is connected through wireless communication;

S2, satellite signal receiving devices are installed on the wireless voltage sensor and the wireless current sensor, and the wireless voltage sensor and the wireless current sensor use satellite second pulses to synchronize clock signals to obtain data time scales when collecting signals ;

S3, the cloud-edge collaborative technology of sampling data, completes the harmonic analysis and quality analysis of voltage and current signals in real time at the "edge end", and combines time scale information with voltage and current signal acquisition data, edge computing results, and edge computing results Including voltage and current harmonic components, mixed coding and direct access to the cloud.

Preferably, the calculation method of resistive current includes:

First, the edge computing data is decoded in the cloud, and based on the unique voltage sampling point of the same substation, the characteristics of MOAs distributed in different locations of the whole substation are compared to achieve real-time comparison and analysis;

Second, carry out intelligent analysis, based on the advantages of cloud data processing, and based on a large amount of historical data to realize the intelligent judgment of MOA damp.

Beneficial effects of the present invention:

1. The present invention realizes the synchronous measurement of resistive current by the zinc oxide arrester equipment in the substation, that is, realizes the synchronous measurement of voltage and current, and more accurately and effectively judges the operating safety state of the arrester.

2. The present invention realizes the wireless data uploading of the resistive current of the substation zinc oxide arrester, reduces the operator's running back and forth to read the meter, greatly improves the work efficiency, enhances the intelligence of the substation equipment, and accumulates experience for improving the automation level of the substation; The real-time monitoring level of power station operation reduces management costs.

Description of drawings

Fig. 1 is the overall structure diagram of the present invention;

Figure 2 is a structural diagram of the wireless current sensor.

Detailed ways

The present invention will be further introduced below in conjunction with the accompanying drawings and specific embodiments.

The reference signs in the accompanying drawings include: high-voltage bus 1, A-phase arrester 21, B-phase arrester 22, C-phase arrester 23, first wireless current sensor 31, second wireless current sensor 32, third wireless current sensor 33, Wireless voltage sensor 4, power supply module 41, data acquisition module 42, signal conditioning module 43, signal acquisition module 44, processor 45, data storage module 46, processor 47, LAN48, CPU-based edge computing CMA49, on-site data processing terminal 5. Beidou satellite 6. Voltage transformer 7.

Example 1:

The wireless zinc oxide arrester resistive current monitoring system, as shown in Figure 1, includes a voltage transformer 7, a wireless voltage sensor 4, a wireless current sensor and a field data processing terminal 5, and the wireless current sensor includes a first wireless current sensor 31, a second wireless current sensor Wireless current sensor 32, the 3rd wireless current sensor 33, three-phase lightning arrester comprises A phase lightning arrester 21, B phase lightning arrester 22 and C phase lightning arrester 23, the A phase of three-phase lightning arrester 21, B phase and one end of C phase and high-voltage busbar respectively Phase A, Phase B, and Phase C of 1 are electrically connected, the other end of Phase A, Phase B, and Phase C of the three-phase arrester 21 is grounded, and the voltage transformer 7 is connected to the busbar of the alternating current; the wireless voltage sensor 4 is set on Connect the wires connecting the voltage transformer 7 and the ground wire, the number of wireless current sensors is set to 3 and they are respectively sleeved on the wires connecting the A phase, B phase, and C phase of the arrester and the ground wire; the wireless current sensor and the wireless current sensor The voltage sensors 4 are all signal-connected with the on-site data processing terminal 5 through wireless communication.

As shown in Figure 2, the wireless current sensor includes a signal acquisition module 44, a signal conditioning module 43, a processor 45, a data storage module 46, a control module and a power supply module 41,

Signal collection module 44 is used for collecting current signal;

The signal conditioning module 43 transmits the collected current signal to the processor 45 after conditioning;

The processor 45 is used to process the conditioned current signal. The processor 45 is connected to the CPU-based edge computing CMA through the LAN signal, and the CPU-based edge computing CMA is connected to the on-site data processing terminal 5 through WIFI communication;

Data storage module 46 is used for storing the processed data;

The power module 41 is used to provide power.

Preferably, an ADC high-speed acquisition chip is arranged between the signal conditioning module 43 and the processor 45 .

Preferably, the processor 45 is an FPGA processor 45 .

Preferably, the data storage module 46 is a high-speed SRAM.

Preferably, the CMA is signal-connected with the on-site data processing terminal 5 through WIFI communication.

Preferably, the control module sends the position of the current sensor to the remote terminal through GPS communication.

In this embodiment, the wireless voltage sensor 4 and the wireless current sensor are equipped with a GPS signal receiving device, the GPS signal receiving device is connected to the processor 45 signal, and the GPS signal receiving device is used to receive the Beidou satellite 6 signal.

This embodiment also includes a method for monitoring the resistive current of a wireless zinc oxide arrester, including the following steps:

S1, a wireless current sensor is installed between the arrester and the ground wire, a wireless voltage sensor 4 is installed between the voltage transformer 7 and the ground wire, and a field data processing terminal 5 is installed on site. Both the wireless current sensor and the wireless voltage sensor 4 are connected to the field The data processing terminal 5 is connected by means of wireless communication;

S2, a satellite signal receiving device is installed on the wireless voltage sensor 4 and the wireless current sensor, and the wireless voltage sensor 4 and the wireless current sensor use the satellite second pulse to synchronize the clock signal to obtain the data time scale when collecting signals;

S3, the cloud-edge collaborative technology of sampling data, completes the harmonic analysis and quality analysis of voltage and current signals in real time at the "edge end", and combines time scale information with voltage and current signal acquisition data, edge computing results, and edge computing results Including voltage and current harmonic components, mixed coding and direct access to the cloud.

Preferably, the calculation method of resistive current includes:

First, the edge computing data is decoded in the cloud, and based on the unique voltage sampling point of the same substation, the characteristics of MOAs distributed in different locations of the whole substation are compared to achieve real-time comparison and analysis;

Second, carry out intelligent analysis, based on the advantages of cloud data processing, and based on a large amount of historical data to realize the intelligent judgment of MOA damp.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention, therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. The resistive current monitoring system of the wireless zinc oxide arrester is characterized in that it includes a voltage transformer, a wireless voltage sensor, a wireless current sensor and an on-site data processing terminal, and one end of the A phase, the B phase and the C phase of the three-phase arrester is connected to the The A phase, B phase and C phase of the AC power are electrically connected, the other end of the A phase, B phase and C phase of the three-phase arrester is grounded, and the voltage transformer is connected to the bus bar of the AC power; the wireless voltage sensor is set On the wire connecting the voltage transformer and the ground wire, the number of the wireless current sensors is set to 3 and are respectively set on the wires connecting the A phase, B phase, and C phase of the arrester and the ground wire; Both the wireless current sensor and the wireless voltage sensor are signal-connected with the field data processing terminal through wireless communication. 2. The wireless zinc oxide arrester resistive current monitoring system according to claim 1, wherein satellite signal receiving devices are installed on the wireless voltage sensor and the wireless current sensor. 3. wireless zinc oxide lightning arrester resistive current monitoring system according to claim 1, is characterized in that, described wireless current sensor comprises signal acquisition module, signal conditioning module, processor, data storage module, control module and power supply module, The signal acquisition module is used to acquire current signals; The signal conditioning module transmits the collected current signal to the processor after conditioning; The processor is used to process the conditioned current signal, and the processor is connected to a CMA through a local area network signal, and the CMA is connected to the on-site data processing terminal signal through wireless communication; The data storage module is used for storing the processed data; The power module is used to provide power. 4. The wireless zinc oxide arrester resistive current monitoring system according to claim 3, wherein an ADC high-speed acquisition chip is arranged between the signal conditioning module and the processor. 5. The wireless zinc oxide arrester resistive current monitoring system according to claim 3, wherein the processor is an FPGA processor. 6. The wireless zinc oxide arrester resistive current monitoring system according to claim 3, wherein the data storage module is a high-speed SRAM. 7. The wireless zinc oxide arrester resistive current monitoring system according to claim 3, characterized in that, the CMA is connected to the on-site data processing terminal signal through a WIFI communication mode. 8. The wireless zinc oxide arrester resistive current monitoring system according to claim 3, wherein the control module sends the positions of the wireless current sensor and the wireless voltage sensor to a remote terminal through a GPS communication module. 9. The method for monitoring the resistive current of a wireless zinc oxide arrester, comprising the following steps: S1, installing a wireless current sensor between the lightning arrester and the ground wire, installing a wireless voltage sensor between the voltage transformer and the ground wire, and installing a field data processing terminal on site, the wireless current sensor and the wireless voltage sensor are both compatible with the The on-site data processing terminal is connected through wireless communication; S2, satellite signal receiving devices are installed on the wireless voltage sensor and the wireless current sensor, and the wireless voltage sensor and the wireless current sensor use satellite second pulses to synchronize clock signals to obtain data time scales when collecting signals ; S3, the cloud-edge collaborative technology of sampling data, completes the harmonic analysis and quality analysis of voltage and current signals in real time at the "edge end", and combines time scale information with voltage and current signal acquisition data, edge computing results, and edge computing results Including voltage and current harmonic components, mixed coding and direct access to the cloud. 10. The wireless zinc oxide arrester resistive current monitoring system according to claim 9, wherein the calculation method of the resistive current comprises: The edge computing data is decoded in the cloud, and based on the unique voltage sampling point of the same substation, the characteristics of MOA distributed in different locations of the whole station are compared to realize real-time comparison and analysis; Second, carry out intelligent analysis, based on the advantages of cloud data processing, and based on a large amount of historical data to realize the intelligent judgment of MOA damp.

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