A discharge protection monitoring and early warning device for high-voltage switchgear

Abstract

This utility model discloses a discharge protection monitoring and early warning device for high-voltage switchgear, including a high-voltage switchgear body, a protection monitoring unit, an ionization pulse sensor, and a discharge energy impact sensor. The protection monitoring unit is connected to the ionization pulse sensor via an RF coaxial cable to collect the pulse signals acquired by the ionization pulse sensor. The protection monitoring unit interacts with the discharge energy impact sensor via a CAN bus to collect data on changes in sound, vibration, pressure, smoke, and ozone content during discharge. The protection monitoring unit is also connected to a main circuit voltage transformer via a two-core cable to collect the voltage signals from the main circuit voltage transformer to form a phase diagram. This allows for comprehensive analysis and judgment of the insulation degradation and discharge type of the high-voltage switchgear body, which is beneficial for maintenance personnel to accurately formulate maintenance plans after partial discharge occurs, achieving efficient maintenance and avoiding large-scale power outages.

Description

Technical Field

[0001] The utility model relates to the technical field of high-voltage switch cabinets, and specifically relates to a discharge protection monitoring and warning device for high-voltage switch cabinets. Background Art

[0002] As is well known, current high-voltage switch cabinet discharge monitoring products are only limited to the collection of partial discharge signals, equipped with transient earth voltage sensors and ultrasonic sensors, usually used alone or in combination. Their function is to detect the electromagnetic wave signals and ultrasonic signals generated when partial discharge occurs in high-voltage equipment, and to judge whether the insulation of the high-voltage switch cabinet is abnormal and issue an alarm. In practical applications, it only tells the maintenance personnel whether there is a problem, which is far from enough. There are two reasons: First, it cannot calibrate the partial discharge characterization indicators such as the discharge type, and the integrity and accuracy of the maintenance plan formulation will deviate, which is not conducive to the implementation of efficient maintenance; Second, due to the lack of sensor types, it cannot comprehensively collect and judge the characteristic signals of electricity, heat, light, vibration, and ozone generated during discharge, and there are certain limitations in the accuracy of partial discharge judgment and the early warning of sudden rapid discharge. Summary of the Invention

[0003] The purpose of the utility model is to provide a discharge protection monitoring and warning device for high-voltage switch cabinets, which can effectively solve the problems raised in the background art.

[0004] To achieve the above purpose, the utility model provides the following technical solution: A discharge protection monitoring and warning device for high-voltage switch cabinets, including the high-voltage switch cabinet body and a protection monitoring unit, an ionization pulse sensor, and a discharge energy impact sensor that are configured to support the high-voltage switch cabinet body. The protection monitoring unit is connected to the ionization pulse sensor by a radio frequency coaxial cable. The ionization pulse sensor generates pulse signals during the gas ionization process caused by high voltage breakdown of gas when collecting discharge. The protection monitoring unit is used to collect the pulse signals collected by the ionization pulse sensor; The protection monitoring unit exchanges data with the discharge energy impact sensor through a CAN bus. The discharge energy impact sensor is used to collect the energy impact signals, as well as the smoke and ozone concentration signals generated when the high-voltage switch cabinet body discharges. The protection monitoring unit is used to collect the changes in sound, vibration, pressure, smoke, and ozone content during discharge collected by the discharge energy impact sensor; The protection monitoring unit is also connected to the main circuit voltage transformer through a two-core cable. The protection monitoring unit is used to collect the voltage signals of the main circuit voltage transformer to form a phase diagram; The protection monitoring unit comprehensively analyzes various signal changes during discharge, combines the discharge phase diagram, and analyzes and judges the insulation deterioration situation and discharge type situation of the high-voltage switch cabinet body.

[0005] Furthermore, the protection monitoring unit adopts a high-efficiency, low-power, and high-speed 32-bit microcontroller CPU based on the FSMC bus, with an external 8MSRAM and 16MFlash as the main processing system. At the same time, it connects to Ethernet module, WIFI module, acquisition module, clock module, non-volatile memory module, RS485 communication module and sensor module through SPI, IIC, UART and CAN peripheral interfaces to form a peripheral processing system. The input of all sensor modules adopts electromagnetic isolation and optocoupler isolation technology.

[0006] Furthermore, the protection and monitoring unit is also equipped with a signal conditioning circuit to improve the acquisition sensitivity. The signal conditioning circuit adopts a four-stage conditioning method. The first stage is a follower circuit, which uses a high-slew rate, high-bandwidth operational amplifier and is designed as a follower circuit. The second stage is a fourth-order active filter circuit in low-pass mode. The third stage is a current-mode amplifier circuit, which uses the frequency-insensitive characteristic of current amplifiers to amplify high-frequency small signals, which is convenient for signal processing in subsequent circuits. The fourth stage is an active detector circuit, which detects the amplified high-frequency signal and reduces the frequency to a medium-level frequency band that can be acquired by the ADC.

[0007] Furthermore, the protection monitoring unit is connected to the main circuit voltage signal of the secondary side of the high-voltage PT of the main circuit voltage transformer, which is used to generate the phase at the moment of discharge. It adopts a three-stage conditioning circuit. The first stage is a follower circuit, which uses a general operational amplifier and is designed as a follower circuit. The second stage is a fourth-order active filter circuit in low-pass mode. The third stage is a voltage-type amplifier circuit, which conditions the signal into a voltage input acquisition module that can be directly acquired.

[0008] Furthermore, the pulse signal generated by the ionization pulse sensor includes electromagnetic wave signals and ultrasonic signals. The ionization pulse sensor acquires the electromagnetic wave signals generated during discharge through capacitive coupling technology, and the ionization pulse sensor acquires the ultrasonic signals generated during discharge using a piezoelectric ceramic sensor.

[0009] Furthermore, the discharge energy impact sensor is an intelligent sensor, employing a high-efficiency, low-power, and high-speed 32-bit microcontroller CPU as the main system. It connects to the acquisition module and CAN communication module via SPI and CAN peripheral interfaces to form a peripheral processing system. The smoke sensor, ozone concentration sensor, sound sensor, vibration sensor, and pressure transformer are connected to their respective conditioning circuits via cables. The conditioning circuits employ a three-stage conditioning scheme: the first stage is a follower circuit using a general-purpose operational amplifier; the second stage is a second-order active filter circuit; and the third stage is a voltage-type amplifier circuit that conditions the signal into a directly measurable voltage input to the acquisition module. All sensor inputs utilize electromagnetic isolation and optocoupler isolation technologies.

[0010] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0011] This high-voltage switchgear discharge protection monitoring and early warning device collects electromagnetic wave signals and ultrasonic signals generated during the discharge process through ionization pulse sensors and discharge energy impact sensors, as well as changes in sound, vibration, smoke, and ozone content generated during strong discharges. It reflects the degree and speed of insulation degradation in the switchgear, and has a good identification effect on sudden and rapid insulation degradation. This helps maintenance personnel to accurately formulate maintenance plans after partial discharge occurs, achieve efficient maintenance, and avoid large-scale power outages that could have adverse effects on society and the national economy. Attached Figure Description

[0012] Figure 1 This is a diagram showing the overall frame connection of this utility model;

[0013] Figure 2 This is a connection diagram of the protection and monitoring unit module of this utility model;

[0014] Figure 3 This is a circuit diagram of the signal acquisition part of the protection and monitoring unit of this utility model;

[0015] Figure 4 This is a block diagram of the discharge energy impact sensor of this utility model.

[0016] Figure 5 This is a circuit diagram of the signal acquisition part of the discharge energy impact sensor of this utility model.

[0017] In the diagram: 1. Protection and monitoring unit; 2. Ionization pulse sensor; 3. Discharge energy impact sensor; 4. High-voltage switchgear body; 5. Main circuit voltage transformer. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Please see Figure 1This embodiment provides a discharge protection monitoring and early warning device for a high-voltage switchgear, including a high-voltage switchgear body 4 and a protection monitoring unit 1, an ionization pulse sensor 2, and a discharge energy impact sensor 3, which are configured in conjunction with the high-voltage switchgear body 4. The protection monitoring unit 1 is connected to the ionization pulse sensor 2 via a radio frequency coaxial cable. The radio frequency coaxial cable has the characteristics of low signal transmission loss, strong anti-interference ability, wide bandwidth, and high shielding performance. The ionization pulse sensor 2 generates a pulse signal during the ionization process of gas caused by high voltage breakdown during discharge. The protection monitoring unit 1 is used to collect the pulse signal collected by the ionization pulse sensor 2. The protection monitoring unit 1 uses a CAN bus to exchange data with the discharge energy impact sensor 3. The CAN bus adopts a multi-point communication mode and has high throughput. The system features high data transmission speed (up to 10Mbps), reliable data transmission, and real-time network data transmission, enabling convenient, fast, and accurate proactive data uploading. The discharge energy impact sensor 3 collects energy impact signals generated during the discharge of the high-voltage switchgear body 4, as well as smoke and ozone concentration signals. The protection monitoring unit 1 collects the changes in sound, vibration, pressure, smoke, and ozone content during discharge collected by the discharge energy impact sensor 3. The protection monitoring unit 1 is also connected to the main circuit voltage transformer 5 via a two-core cable, and collects the voltage signal from the main circuit voltage transformer 5 to form a phase diagram. The protection monitoring unit 1 comprehensively analyzes and judges the insulation degradation and discharge type of the high-voltage switchgear body 4 by considering the changes in various signals generated during discharge and the overall discharge phase diagram.

[0020] like Figure 2 As shown, in the above embodiment, the protection monitoring unit 1 uses a high-efficiency, low-power, high-speed 32-bit microcontroller CPU based on the FSMC bus, with external 8MSRAM and 16MFlash as the main processing system. Simultaneously, it connects to an Ethernet module, WIFI module, acquisition module, clock module, non-volatile memory module, RS485 communication module, and sensor module via SPI, IIC, UART, and CAN peripheral interfaces to form a peripheral processing system. All sensor module inputs employ electromagnetic isolation and optocoupler isolation technology. To improve the signal acquisition sensitivity of the protection monitoring unit 1, retain useful frequency band signals to the maximum extent, and effectively filter out interference signals, such as... Figure 3As shown: The protection monitoring unit 1 is equipped with a signal conditioning circuit to improve the acquisition sensitivity. The signal conditioning circuit adopts a four-stage conditioning method. The first stage is a follower circuit, which uses a high-slew rate, high-bandwidth operational amplifier and is designed as a follower circuit to increase the input impedance, reduce the primary signal attenuation, and improve the signal transmission quality. The second stage is a fourth-order active filter circuit in bandpass mode, which filters out interference signals to the maximum extent, retains useful signals, and reduces signal attenuation. The third stage is a current-mode amplifier circuit, which uses the frequency-insensitive characteristic of current amplifiers to amplify high-frequency small signals, which is convenient for signal processing in subsequent circuits. The fourth stage is a detector circuit, which detects the amplified high-frequency signal and reduces the frequency to a frequency band that can be acquired by a medium-level ADC. In order to improve the signal acquisition performance, this detector circuit adopts a high-performance active detector circuit.

[0021] In addition, the protection monitoring unit 1 receives the main circuit voltage signal from the secondary side of the high-voltage PT of the main circuit voltage transformer 5. This signal is used to generate the phase at the moment of discharge. A three-stage conditioning circuit is employed to filter out interference and noise, maximizing the retention of the 50Hz power frequency signal. The first stage is a follower circuit, using a general-purpose operational amplifier designed as a follower circuit to increase input impedance, reduce primary signal attenuation, and improve signal transmission quality. The second stage is a fourth-order active filter circuit in low-pass mode to maximize the filtering of high-frequency interference signals and reduce signal attenuation. The third stage is a voltage-type amplifier circuit that conditions the signal into a voltage input acquisition module that can be directly acquired. The acquisition of the main circuit phase is used to determine the discharge type, solving the problem mentioned in the background technology that only providing maintenance personnel with information on the presence or absence of discharge affects the completeness and accuracy of maintenance plans and hinders efficient maintenance execution.

[0022] In the above embodiments, the pulse signal generated by the ionization pulse sensor 2 includes electromagnetic wave signals and ultrasonic signals. The ionization pulse sensor 2 acquires the electromagnetic wave signals generated during discharge using capacitive coupling technology, and the ionization pulse sensor 2 uses a piezoelectric ceramic sensor to acquire the ultrasonic signals generated during discharge. The electromagnetic wave signals are sensitive to internal discharges in insulation, while the ultrasonic signals are sensitive to surface discharges in dielectrics. The sensor combines the electromagnetic wave and ultrasonic signals generated during discharge for joint analysis and judgment, solving the problem mentioned in the background technology that the use of a simple transient ground voltage sensor is insensitive to surface discharge models and insulator surface discharge models.

[0023] In this embodiment, the discharge energy impact sensor 3 is an intelligent sensor that collects the energy impact signal generated during discharge, as well as smoke and ozone concentration signals. When a high-voltage discharge occurs in the high-voltage switchgear body 4, energy is radiated outward, generating phenomena such as electricity, heat, sound, vibration, smoke, and ozone gas. When the discharge energy is strong, the impact sensor can collect sound, vibration, pressure, smoke concentration, and ozone content. It utilizes acoustic signature analysis technology, vibration waveform spectrum analysis technology, changes in environmental pressure and smoke density, and environmental ozone content to reflect the discharge phenomenon (ozone is generated during discharge by ionizing the air). When the sensor detects drastic changes in these signals, it can indicate that the switchgear insulation is rapidly deteriorating, solving the problem mentioned in the background technology where the incomplete detection sensors have limitations in providing early warning of sudden insulation deterioration. Specifically, as... Figure 4 As shown: The discharge energy impact sensor 3 of this utility model uses a high-efficiency, low-power, high-speed 32-bit microcontroller CPU as the main system. It connects to the acquisition module and CAN communication module via SPI and CAN peripheral interfaces to form a peripheral processing system. The smoke sensor, ozone concentration sensor, sound sensor, vibration sensor, and pressure transformer are connected to the corresponding conditioning circuits via cables. The conditioning circuits adopt a three-stage conditioning scheme. For example... Figure 5 As shown: The first stage is a follower circuit, which uses a general-purpose operational amplifier and is designed as a follower circuit to increase the input impedance, reduce the primary signal attenuation, and improve the signal transmission quality; the second stage is a second-order active filter circuit, which filters out high-frequency interference signals to the maximum extent and reduces signal attenuation; the third stage is a voltage-type amplifier circuit, which conditions the signal into a voltage input acquisition module that can be directly acquired. All sensor inputs use electromagnetic isolation and optocoupler isolation technology.

[0024] In summary, this utility model's high-voltage switchgear discharge protection monitoring and early warning device can determine the phase of the discharge and thus the discharge type by collecting the main circuit voltage waveform, enhancing the completeness and accuracy of maintenance plan formulation and facilitating efficient maintenance execution. Secondly, by collecting electromagnetic wave signals and ultrasonic signals generated during the discharge process through the ionization pulse sensor 2 and the discharge energy impact sensor 3, as well as changes in sound, pressure, vibration, smoke, and ozone content generated during intense discharge, it reflects the degree and speed of switchgear insulation degradation. It has a good identification effect on sudden and rapid insulation degradation. Furthermore, the increased types and applications of detection sensors allow for the collection of more characteristic parameters generated by the discharge, better solving the current limitations of early warning for sudden insulation degradation. This avoids large-scale power outages caused by misjudgments by maintenance personnel after partial discharge occurs in the switchgear, preventing adverse impacts on society and the national economy.

[0025] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0026] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A discharge protection monitoring and early warning device for a high-voltage switchgear, comprising a high-voltage switchgear body (4) and a protection monitoring unit (1), an ionization pulse sensor (2), and a discharge energy impact sensor (3) configured in conjunction with the high-voltage switchgear body (4), characterized in that: The protection monitoring unit (1) is connected to the ionization pulse sensor (2) by a radio frequency coaxial cable. The ionization pulse sensor (2) generates a pulse signal during the gas ionization process caused by high voltage breakdown of gas during the discharge. The protection monitoring unit (1) is used to collect the pulse signal collected by the ionization pulse sensor (2). The protection monitoring unit (1) uses a CAN bus to interact with the discharge energy impact sensor (3). The discharge energy impact sensor (3) is used to collect the energy impact signal generated by the high voltage switchgear body (4) during discharge, as well as the smoke and ozone concentration signals. The protection monitoring unit (1) is used to collect the changes in sound, vibration, pressure, smoke and ozone content collected by the discharge energy impact sensor (3) during discharge. The protection monitoring unit (1) is also connected to the main circuit voltage transformer (5) via a two-core cable. The protection monitoring unit (1) is used to collect the voltage signal of the main circuit voltage transformer (5) to form a phase diagram. The protection monitoring unit (1) integrates the changes of various signals generated during discharge, integrates the discharge phase diagram, and analyzes and judges the insulation degradation and discharge type of the high voltage switchgear body (4).

2. The discharge protection monitoring and early warning device for high-voltage switch cabinet according to claim 1, characterized in that: The protection monitoring unit (1) adopts a high-efficiency, low-power, and high-speed 32-bit single-chip microcomputer CPU based on the FSMC bus, with an external 8MSRAM and 16MFlash as the main processing system. At the same time, it connects to the Ethernet module, WIFI module, acquisition module, clock module, non-volatile memory module, RS485 communication module and sensor module through SPI, IIC, UART and CAN peripheral interfaces to form a peripheral processing system. The input of all sensor modules adopts electromagnetic isolation and optical isolation technology.

3. The discharge protection monitoring and early warning device for high-voltage switch cabinet according to claim 2, characterized in that: The protection monitoring unit (1) is also equipped with a signal conditioning circuit for improving the acquisition sensitivity. The signal conditioning circuit adopts a four-stage conditioning method. The first stage is a follower circuit, which adopts a high slew rate and high bandwidth operational amplifier and is designed as a follower circuit. The second stage is a fourth-order active filter circuit in low-pass mode. The third stage is a current-type amplifier circuit, which adopts the characteristic of the current amplifier being insensitive to frequency to amplify high-frequency small signals, which is convenient for signal processing of subsequent circuits. The fourth stage is an active detector circuit, which detects the amplified high-frequency signal and reduces the frequency to a medium-level frequency band that can be acquired by the ADC.

4. The discharge protection monitoring and early warning device for high-voltage switch cabinet according to claim 3, characterized in that: The protection monitoring unit (1) is connected to the main circuit voltage signal of the secondary side of the high voltage PT of the main circuit voltage transformer (5) to generate the phase at the moment of discharge. It adopts a three-stage conditioning circuit. The first stage is a follower circuit, which uses a general operational amplifier and is designed as a follower circuit. The second stage is a fourth-order active filter circuit in low-pass mode. The third stage is a voltage-type amplifier circuit, which conditions the signal into a voltage input acquisition module that can be directly acquired.

5. The discharge protection monitoring and early warning device for high-voltage switch cabinet according to claim 1, characterized in that: The pulse signal generated by the ionization pulse sensor (2) includes electromagnetic wave signal and ultrasonic signal. The ionization pulse sensor (2) collects the electromagnetic wave signal generated during discharge through capacitive coupling technology, and the ionization pulse sensor (2) uses a piezoelectric ceramic sensor to collect the ultrasonic signal generated during discharge.

6. The discharge protection monitoring and early warning device for high-voltage switch cabinet according to claim 1, characterized in that: The discharge energy impact sensor (3) is an intelligent sensor. It uses a high-efficiency, low-power, and high-speed 32-bit microcontroller CPU as the main system. It connects the acquisition module and the CAN communication module through the SPI and CAN peripheral interfaces to form a peripheral processing system. The smoke sensor, ozone concentration sensor, sound sensor, vibration sensor, and pressure transformer are connected to the corresponding conditioning circuits through cables. The conditioning circuit adopts a three-stage conditioning scheme. The first stage is a follower circuit, which uses a general operational amplifier and is designed as a follower circuit. The second stage is a second-order active filter circuit. The third stage is a voltage-type amplifier circuit, which conditions the signal into a voltage that can be directly acquired and inputs it to the acquisition module. The inputs of all sensors adopt electromagnetic isolation and optocoupler isolation technology.

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