A detector and detection method for the action status of disconnecting switches in GIS equipment

Abstract

This invention relates to the field of power equipment testing technology, specifically to a detector and method for detecting the operational status of disconnecting switches in GIS equipment. The method first generates an action signal based on a first current; then generates a second current and a trigger signal based on the action signal; next, it calculates the current change rate based on the first and second currents; and based on the trigger signal, it determines whether the current change rate is less than a first threshold. If the current change rate is less than the first threshold, an alarm signal is generated. Finally, it determines whether the closing and opening of the circuit breaker are qualified based on the alarm signal. By detecting the induced current generated on the conductor of the grounding switch in the energized part of the GIS equipment, the opening and closing status of the internal disconnecting switch of the GIS equipment is judged. Regardless of whether the mechanical structure of the equipment is normal, it can accurately determine whether the disconnecting switch is properly closed or open, effectively avoiding faults such as discharge, short circuit, and explosion caused by improper closing or opening of the equipment.

Description

Technical Field

[0001] This invention relates to the field of switchgear testing technology, and more specifically, to a detector and testing method for the operational status of a disconnector switch in a GIS device. Background Technology

[0002] GIS equipment is a fully sealed design, making it impossible to directly observe the opening and closing status of internal components such as disconnect switches. Therefore, there are generally two methods for indicating the opening and closing of disconnect switches in GIS equipment: one is the opening / closing indication via an indicator plate installed inside the disconnect switch mechanism box, and the other is the position indication via the transmission linkage of the disconnect switch operating mechanism. Remote indication methods rely on position signals from auxiliary nodes.

[0003] The specific principle is as follows:

[0004] Upon receiving an operating command, the operating mechanism rotates the main shaft and the crank arm plate mounted on it by a specific angle. The crank arm plate pushes the guide sleeve, insulating rod, and moving contact to move linearly along the centerline of the disconnector, thus achieving the opening and closing operation. Simultaneously, the operating mechanism rotates the opening / closing indicator plate, indicating the opening / closing position corresponding to the disconnector's location. When a transmission linkage is present, one end of it will shift closer to the designated point representing the disconnector's open / closed position. After the operating mechanism completes its operation, it activates the corresponding auxiliary node signal, allowing remote detection to determine whether the disconnector is open or closed.

[0005] Current indication methods all rely entirely on indirect indication from the mechanical structure of the operating mechanism: the opening and closing indicator is driven by the spring or other structure of the operating mechanism, and the indication position changes when the mechanical structure changes; the auxiliary node also relies on changes in the mechanical structure to drive the node to open or close.

[0006] When the operating mechanism malfunctions, or when the internal disconnect conductor driven by the operating mechanism malfunctions or falls off, both methods will fail to accurately reflect the true position of the internal disconnect conductor of the GIS equipment, resulting in defects such as incomplete opening and closing of the equipment, and further leading to serious accidents such as discharge, short circuit, and explosion. Summary of the Invention

[0007] This invention addresses the problem that the aforementioned indication methods cannot accurately reflect the true position of the disconnectors inside GIS equipment, leading to incomplete opening and closing of the equipment and causing serious discharge, short circuit, and explosion accidents. It proposes a detector and detection method for the operating status of disconnectors in GIS equipment. This method first generates an action signal based on a first current; secondly, it generates a second current and a trigger signal based on the action signal; then, it calculates the current change rate based on the first and second currents; and based on the trigger signal, it determines whether the current change rate is less than a first threshold. If the current change rate is less than the first threshold, an alarm signal is generated. Finally, it determines whether the closing and opening are qualified based on the alarm signal. By detecting the induced current generated on the conductor of the grounding disconnector in the energized parts of the GIS equipment, the opening and closing status of the disconnectors inside the GIS equipment is judged. Regardless of whether the mechanical structure of the equipment is normal, it can accurately determine whether the disconnector is in place, effectively avoiding faults such as discharge, short circuit, and explosion caused by incomplete opening and closing of the equipment.

[0008] The specific implementation details of this invention are as follows:

[0009] A GIS equipment disconnect switch operation status detector, connected to the disconnect switch unit; includes a current transformer unit and a processor;

[0010] The input terminal of the current transformer unit is connected to the output terminal of the disconnecting switch unit, and the output terminal of the current transformer unit is connected to the input terminal of the processor.

[0011] The isolating switch unit is used to generate an action signal based on the input first current;

[0012] The current transformer unit is used to generate a second current according to the action signal, record the waveform of the second current and generate a trigger signal;

[0013] The processor first calculates the current change rate based on the first current and the second current; then, based on the trigger signal, it determines whether the current change rate is less than a first threshold. If the current change rate is less than the first threshold, an alarm signal is generated; finally, based on the alarm signal, it determines whether the closing and opening of the disconnecting switch unit are qualified.

[0014] To better implement the present invention, the processor further includes: firstly, calculating the three-phase current imbalance rate based on the second current; then determining whether the three-phase current imbalance rate exceeds a second threshold; if the three-phase current imbalance rate exceeds the second threshold, generating an alarm signal; and finally determining whether the closing and opening of the disconnecting switch unit are qualified based on the alarm signal.

[0015] To better realize the present invention, the disconnecting switch unit further includes a circuit breaker, a first main disconnect switch, a second main disconnect switch, a first grounding disconnect switch, a second grounding disconnect switch, and a third grounding disconnect switch;

[0016] The first main disconnect switch receives a first current at its input terminal and its output terminal is connected to the input terminal of the circuit breaker.

[0017] One end of the first grounding switch is connected between the output terminal of the first main switch and the input terminal of the circuit breaker, and the other end of the first grounding switch is connected to the ground.

[0018] The output terminal of the circuit breaker is connected to the input terminal of the second main disconnect switch;

[0019] One end of the second grounding switch is connected between the output terminal of the circuit breaker and the input terminal of the second main switch, and the other end of the second grounding switch is connected to the ground.

[0020] One end of the third grounding switch is connected between the output end of the second main switch and the ground end, and the other end of the second grounding switch is connected to the ground end.

[0021] To better realize the present invention, the current transformer unit further includes a first current transformer, a second current transformer, and a third current transformer.

[0022] One end of the first current transformer is connected between the first grounding switch and the ground terminal, and the other end of the first current transformer is connected to the first input terminal of the processor.

[0023] One end of the second current transformer is connected between the second grounding switch and the ground terminal, and the other end of the second current transformer is connected to the second input terminal of the processor.

[0024] One end of the third current transformer is connected between the first grounding switch and the ground terminal, and the other end of the third current transformer is connected to the third input terminal of the processor.

[0025] To better realize the present invention, the first current transformer, the second current transformer, and the third current transformer are ZLB-C61-SP1 type closed-loop zero-flux AC leakage current sensors.

[0026] To better realize the present invention, the processor further includes an AD converter and a microcontroller;

[0027] The input terminal of the AD converter is connected to the output terminal of the current transformer unit, and the output terminal of the AD converter is connected to the input terminal of the microcontroller.

[0028] The microcontroller outputs the detection result; the detection result is used to indicate whether the closing and opening of the disconnecting switch unit is qualified.

[0029] To better realize the present invention, the microcontroller is further described as an STC12C5A60S2 microcontroller.

[0030] To better realize the present invention, the AD converter is further described as an HT7038 chip.

[0031] Based on the aforementioned GIS equipment disconnector operation status detector, to better realize the present invention, a GIS equipment disconnector operation status detection method is further proposed. The disconnector operation status detector is connected to the disconnector unit. The disconnector operation status detector includes a current transformer and a processor. The detection method includes first calculating the current change rate based on a first current obtained from the disconnector unit and a second current obtained from the current transformer; then determining whether the current change rate is less than a first threshold based on a trigger signal generated by the current transformer unit; if the current change rate is less than the first threshold, an alarm signal is generated; finally, determining whether the current disconnector's closing and opening operations are qualified based on the alarm signal.

[0032] To better implement the present invention, the detection method further includes calculating the three-phase current imbalance rate based on the second current; then determining whether the three-phase current imbalance rate exceeds a second threshold; if the three-phase current imbalance rate exceeds the second threshold, generating an alarm signal; and finally determining whether the closing and opening of the disconnecting switch unit are qualified based on the alarm signal.

[0033] The present invention has the following beneficial effects:

[0034] (1) This invention determines the opening and closing status of the disconnectors inside the GIS equipment by detecting the induced current generated on the conductor of the grounding disconnector by the energized parts in the GIS equipment. This eliminates the reliance on mechanical mechanisms in traditional methods and realizes automatic detection and judgment of the disconnector position. Regardless of whether the mechanical structure of the equipment is normal, the detector can accurately determine whether the disconnector is in place, effectively avoiding faults such as discharge, short circuit, and explosion caused by the equipment not being in place.

[0035] (2) This invention can be installed on gas-insulated metal-enclosed switchgear in power systems, enabling analysis of each action of the internal disconnecting switch and determining whether the disconnecting switch is in the correct opening or closing position. It is applicable to equipment with voltage levels from 110kV to 500kV and can be widely used on high-voltage and ultra-high-voltage equipment.

[0036] (3) The detector of the present invention does not rely on an external power supply, but uses its own internal power supply to realize real-time detection of the position of the switch without power interruption; the test is simple, does not affect the normal operation of the equipment, and has high reliability. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the main wiring of a 110kV single busbar outgoing line bay provided in an embodiment of the present invention.

[0038] Figure 2 The equivalent circuit diagrams for all disconnectors provided in the embodiments of the present invention are shown below.

[0039] Figure 3 The equivalent circuit diagram for closing the 1511 disconnect switch and opening the 15130 grounding disconnect switch is provided for the embodiments of the present invention.

[0040] Figure 4 The equivalent circuit diagram for opening the 1511 disconnect switch and closing the 15130 grounding disconnect switch is provided for the embodiments of the present invention.

[0041] Figure 5 This is a schematic diagram of the disconnector operation status detector provided in an embodiment of the present invention.

[0042] Figure 6 This is a schematic diagram of the detection process of the disconnector switch operation status detector provided in an embodiment of the present invention.

[0043] Figure 7 The schematic diagram of the processor circuit for the disconnector operation status detector provided in the embodiment of the present invention.

[0044] Figure 8 The schematic diagram of the AD converter circuit for the isolating switch operation status detector provided in the embodiment of the present invention.

[0045] Figure 9 This is a schematic diagram of a current transformer structure provided in an embodiment of the present invention.

[0046] Figure 10 The schematic diagram of the printer unit circuit for the isolating switch operation status detector provided in the embodiment of the present invention.

[0047] Figure 11 The schematic diagram of the liquid crystal display unit circuit for the disconnector switch operation status detector provided in the embodiment of the present invention.

[0048] Figure 12 The schematic diagram of the real-time clock unit circuit for the isolating switch operation status detector provided in the embodiment of the present invention.

[0049] Figure 13 The schematic diagram of the keyboard unit circuit for the isolating switch operation status detector provided in the embodiment of the present invention. Detailed Implementation

[0050] To more clearly illustrate the technical solutions of the embodiments of the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments, and therefore should not be regarded as a limitation on the scope of protection. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0052] Example 1:

[0053] This embodiment proposes a method for detecting the operational status of a disconnector switch in a GIS device. The method connects a disconnector switch operational status detector to a disconnector switch unit. The detector includes a current transformer and a processor. The detection method includes: first, calculating the current change rate based on a first current obtained from the disconnector switch unit and a second current obtained from the current transformer; then, determining whether the current change rate is less than a first threshold based on a trigger signal generated by the current transformer unit; if the current change rate is less than the first threshold, generating an alarm signal; and finally, determining whether the closing and opening of the current disconnector switch are qualified based on the alarm signal.

[0054] Furthermore, the detection method also includes calculating the three-phase current imbalance rate based on the second current; then determining whether the three-phase current imbalance rate exceeds a second threshold; if the three-phase current imbalance rate exceeds the second threshold, generating an alarm signal; and finally determining whether the closing and opening of the disconnecting switch unit are qualified based on the alarm signal.

[0055] Working principle: This embodiment first generates an action signal based on a first current; then generates a second current and a trigger signal based on the action signal; then calculates the current change rate based on the first and second currents; and determines whether the current change rate is less than a first threshold based on the trigger signal. If the current change rate is less than the first threshold, an alarm signal is generated; finally, it determines whether the closing and opening are qualified based on the alarm signal. By detecting the induced current generated on the grounding switch conductor by the live parts in the GIS equipment, the opening and closing status of the internal switch of the GIS equipment is judged. Regardless of whether the mechanical structure of the equipment is normal, it can accurately determine whether the isolating switch is in place, effectively avoiding faults such as discharge, short circuit, and explosion caused by the equipment not being in place.

[0056] Example 2:

[0057] This embodiment is based on the above embodiment 1, such as... Figure 1 , Figure 2 , Figure 3 , Figure 4 The following is a detailed description using a specific embodiment.

[0058] This embodiment provides a device for monitoring the opening and closing actions of disconnecting switches inside gas-insulated metal-enclosed switchgear (GIS). Based on the detection and analysis of induced current, this embodiment provides a more reliable assessment of the disconnecting switch status, effectively preventing serious malfunctions caused by incomplete opening or closing of the switch. The key aspects of this embodiment are the acquisition of micro-current signals and the method for determining the signal current.

[0059] This embodiment can analyze the operation of each disconnecting switch inside the equipment and determine whether the disconnecting switch is in the correct opening or closing position. It is applicable to equipment with voltage levels from 110kV to 500kV and can be widely used in high voltage and ultra-high voltage equipment.

[0060] This embodiment presents a method for real-time detection of the switch position without power interruption, utilizing the device's internal power supply instead of an external power source. The method is simple to test, does not affect the normal operation of the device, and has high reliability. Its basic principle is as follows:

[0061] During normal power supply, the initial state is that the busbar conductor is energized, the grounding switch is closed, and the main isolating switch is open. Due to the equivalent capacitance between the switches, a microampere-level ground current will be induced in the spacer conductor and the grounding switch. After the grounding switch operates, the busbar conductor is energized, the grounding switch is open, and the main isolating switch is open. At this time, because there are two breaks between the grounding switch and the energized conductor, the induced ground current will be greatly reduced. Therefore, by installing a current sensor on the grounding electrode of the grounding switch to monitor and record the current waveform for a period of time after the grounding switch knob is turned, it can be determined whether the grounding switch has actually opened.

[0062] The main isolating switch can be used to change the number of breaks between the grounding electrode and the conductor by switching on and off the switch and the grounding switch, and then the same principle can be used to make the determination.

[0063] When the busbar is energized and all disconnectors are open, its equivalent circuit and the current flowing through the 15130 grounding disconnector are as follows: Figure 2 As shown.

[0064] Figure 2 In the diagram, Us represents the induced electromotive force; C1 is the equivalent capacitance of the 1511 disconnect switch; C2 is the equivalent capacitance of the 15130 grounding switch; C3 is the equivalent capacitance of the remaining parts; i2 is the current flowing through the 15130 grounding switch; and ω is the system voltage angular frequency.

[0065]

[0066] After closing disconnector 1511, disconnector 15130 remains open. Its equivalent circuit diagram and the current flowing through the 15130 grounding switch will change as follows: Figure 3 ;

[0067] After closing disconnector 15130, disconnector 1511 remains open. Its equivalent circuit diagram and the current flowing through disconnector 15130 will change as follows: Figure 4 ;

[0068] The rate of change of current before and after the disconnector operation is δ=(I'-I) / I. Where, I is the current detected by the high-precision current transformer before operation, and I' is the current detected by the high-precision current transformer after operation;

[0069] Three-phase current imbalance rate:

[0070]

[0071] Among them, IA, IB, and IC are the induced current values ​​detected by the high-precision current transformers of phase A, phase B, and phase C of the equipment, respectively.

[0072] The judgment method in this embodiment can realize the opening and closing judgment of all disconnectors and circuit breakers inside the GIS equipment.

[0073] Logic for judging test data:

[0074] The alarm signal is triggered when the change in the test value before and after the switch action does not match the theoretical change and reaches the following threshold: I is the current detected by the high-precision current transformer before the action, and I' is the current detected by the high-precision current transformer after the action.

[0075] Logically, when I' increases compared to I, the rate of change of current δ = (I'-I) / I < a, including the case where δ is negative.

[0076] When I' should be smaller than I, and δ = (I - I') / I < a, this includes the case where δ is negative.

[0077] Where 'a' is the set first threshold;

[0078] Note the signal: the device should issue an alarm signal when the test value falls within the following range;

[0079] Three-phase current imbalance rate Where IA, IB, and IC are the test values ​​of the three-phase induced current of the device A, B, and C, respectively, and b is the set second threshold.

[0080] A, B, and C refer to the phases in the power system. High-voltage transmission systems are all three-phase systems, and the structures of the three-phase equipment are completely identical. The system is usually named and distinguished by phase A, phase B, and phase C. In this embodiment, the detectors mentioned above will also be installed on the three-phase equipment. Since the structures are completely identical, only a single phase is described in the figure.

[0081] This embodiment determines the opening and closing status of the disconnectors inside the GIS equipment by detecting the induced current generated on the conductor of the grounding disconnector by the energized parts in the GIS equipment. This eliminates the reliance on mechanical mechanisms in traditional methods and realizes electrical detection and judgment of the disconnector position. Regardless of whether the mechanical structure of the equipment is normal, this device can accurately determine whether the disconnector is fully open or closed, effectively avoiding faults such as discharge, short circuit, and explosion caused by improper opening or closing of the equipment.

[0082] The other parts of this embodiment are the same as those in Embodiment 1 above, so they will not be described again.

[0083] Example 3:

[0084] Based on any one of Embodiments 1-2 above, this embodiment proposes a GIS equipment disconnect switch operation status detector.

[0085] Connected to the disconnector unit; includes a current transformer unit and a processor;

[0086] The input terminal of the current transformer unit is connected to the output terminal of the disconnecting switch unit, and the output terminal of the current transformer unit is connected to the input terminal of the processor.

[0087] The isolating switch unit is used to generate an action signal based on the input first current;

[0088] The current transformer unit is used to generate a second current according to the action signal, record the waveform of the second current and generate a trigger signal;

[0089] The processor first calculates the current change rate based on the first current and the second current; then, based on the trigger signal, it determines whether the current change rate is less than a first threshold. If the current change rate is less than the first threshold, an alarm signal is generated; finally, based on the alarm signal, it determines whether the closing and opening of the disconnecting switch unit are qualified.

[0090] Furthermore, the processor also includes: firstly, calculating the three-phase current imbalance rate based on the second current; then determining whether the three-phase current imbalance rate exceeds a second threshold; if the three-phase current imbalance rate exceeds the second threshold, generating an alarm signal; and finally determining whether the closing and opening of the disconnecting switch unit are qualified based on the alarm signal.

[0091] Furthermore, the disconnecting switch unit includes a circuit breaker, a first main disconnect switch, a second main disconnect switch, a first grounding disconnect switch, a second grounding disconnect switch, and a third grounding disconnect switch;

[0092] The first main disconnect switch receives a first current at its input terminal and its output terminal is connected to the input terminal of the circuit breaker.

[0093] One end of the first grounding switch is connected between the output terminal of the first main switch and the input terminal of the circuit breaker, and the other end of the first grounding switch is connected to the ground.

[0094] The output terminal of the circuit breaker is connected to the input terminal of the second main disconnect switch;

[0095] One end of the second grounding switch is connected between the output terminal of the circuit breaker and the input terminal of the second main switch, and the other end of the second grounding switch is connected to the ground.

[0096] One end of the third grounding switch is connected between the output end of the second main switch and the ground end, and the other end of the second grounding switch is connected to the ground end.

[0097] Furthermore, the current transformer unit includes a first current transformer, a second current transformer, and a third current transformer;

[0098] One end of the first current transformer is connected between the first grounding switch and the ground terminal, and the other end of the first current transformer is connected to the first input terminal of the processor.

[0099] One end of the second current transformer is connected between the second grounding switch and the ground terminal, and the other end of the second current transformer is connected to the second input terminal of the processor.

[0100] One end of the third current transformer is connected between the first grounding switch and the ground terminal, and the other end of the third current transformer is connected to the third input terminal of the processor.

[0101] Furthermore, the processor includes an AD converter and a microcontroller;

[0102] The input terminal of the AD converter is connected to the output terminal of the current transformer unit, and the output terminal of the AD converter is connected to the input terminal of the microcontroller.

[0103] The microcontroller outputs the detection result; the detection result is used to indicate whether the closing and opening of the disconnecting switch unit is qualified.

[0104] The other parts of this embodiment are the same as any one of the above embodiments 1-2, so they will not be described again.

[0105] Example 4:

[0106] This embodiment is based on any one of embodiments 1-3 above, such as Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 , Figure 10 , Figure 11 , Figure 12 , Figure 13 The specific structure of the disconnector operation status detector is described in detail using a specific embodiment.

[0107] The disconnector operation status detector provided in this embodiment includes 1. a processor, 2. an AD converter, 3. a current transformer, 4. a printer unit, 5. a liquid crystal display unit, 6. a real-time clock unit, and 7. a keyboard unit.

[0108] like Figure 7As shown, the processor uses an STC12C5A60S2 microcontroller, which has two standard serial ports and can drive a printer and an LCD display via serial ports. The microcontroller exchanges data with the real-time clock via analog I2C and with the AD converter via analog SPI. The keyboard interacts with the microcontroller via a tri-state bus converter and parallel port P0.

[0109] like Figure 8 As shown, the AD converter uses the HT7038 series multi-functional high-precision three-phase energy metering chip. The HT7038 series multi-functional high-precision three-phase energy metering chip is suitable for three-phase three-wire and three-phase four-wire applications. The HT7038 integrates a 6-channel second-order Σ-Δ ADC, a reference voltage circuit, and digital signal processing circuits for all power, energy, RMS value, power factor, and frequency measurements. It can measure the active power, reactive power, active and reactive quantities of each phase and the combined phase, and can also measure parameters such as current, voltage RMS value, power factor, phase angle, and frequency of each phase, fully meeting the needs of a three-phase multi-tariff multi-functional energy meter. The HT7038 provides an SPI interface for convenient transmission of metering and calibration parameters with an external MCU; all metering and calibration parameters can be read through the SPI interface.

[0110] like Figure 9 As shown, the induced current flowing through the grounding switch is collected by a precision current transformer. The current transformer adopts a ZLB-C61-SP1 type closed-loop zero-flux AC leakage current sensor. The sensor is installed on the grounding conductor of the grounding switch of the GIS equipment. The collected current is converted into an AC signal of 0-5V by a current transmitter. The signal is then reduced to the range acceptable to the AD converter by a resistor voltage divider. Finally, it is provided to the AD converter through RC filtering.

[0111] like Figure 10 As shown, the printer used is the Weihuang E26 thermal micro printer, which can connect to the microcontroller via a standard serial port and print test data of the test results.

[0112] like Figure 11 As shown, the LCD display uses a DMG85480C050_03WN color display, which has an 854*480 dot matrix resolution and can clearly display test data and real-time curves. The LCD connects to the microcontroller via a standard serial port.

[0113] like Figure 12As shown, the PCF8563 real-time clock is an industrial-grade, low-power, multi-functional clock / calendar chip from PHILIPS, featuring an integrated I2C bus interface. The PCF8563's various alarm functions, timer functions, clock output functions, and interrupt output functions can perform a variety of complex timing services, and can even provide a watchdog function for microcontrollers. It is a highly cost-effective clock chip widely used in products such as electricity meters, water meters, gas meters, telephones, fax machines, portable instruments, and battery-powered instruments. The PCF8563 exchanges data with the microcontroller via the I2C bus.

[0114] like Figure 13 As shown, the keyboard is connected to the parallel port P0 of the microcontroller via a tri-state bus converter 74HC245. The microcontroller reads the operation of the external keyboard through P0 and then executes the corresponding action.

[0115] Pin connection relationship:

[0116] The current transformer outputs U1A, U1AN, U1B, U1BN, U1C, and U1CN are connected to the AD converter pins 1, 2, 4, 5, 7, and 8, respectively; the AD converter pins 25, 26, 27, 28, and 32 are connected to the processor pins 21, 20, 19, 18, and 11, respectively; the real-time clock pins 5 and 6 are connected to the processor pins 28 and 27, respectively; the printer pins 1 and 4 are connected to the processor 43, pins 5 and 6 are connected to the processor 40, pins 12 and 13 are connected to the processor pin 41, and pin 8 is connected to the processor pin 42; the LCD pins 2 and 3 are connected to the processor pins 7 and 5, respectively; the real-time clock pins 5 and 6 are connected to the processor pins 27 and 28, respectively; and the keyboard pins 2-9 are connected to the processor pins 37-30, respectively.

[0117] After receiving the trigger signal to start detection, the detector will record the current waveform for a period of time before and after the trigger. The algorithm set in the detection host will automatically judge the operation status of the disconnect switch and automatically store, output the detection waveform and conclusion.

[0118] The detector provided in this embodiment can be installed on gas-insulated metal-enclosed switchgear in power systems to analyze the operation of each disconnecting switch inside the equipment and determine whether the disconnecting switch is in the correct opening or closing position. It is suitable for equipment with voltage levels from 110kV to 500kV and can be widely used in high-voltage and ultra-high-voltage equipment.

[0119] The other parts of this embodiment are the same as any one of the embodiments 1-3 above, so they will not be described again.

[0120] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A detector for the operational status of a disconnecting switch in a GIS device, connected to a disconnecting switch unit; characterized in that, Includes current transformer units and processors; The input terminal of the current transformer unit is connected to the output terminal of the disconnecting switch unit, and the output terminal of the current transformer unit is connected to the input terminal of the processor. The disconnecting switch unit is used to generate an action signal based on the input first current; The current transformer unit is used to generate a second current according to the action signal, record the waveform of the second current and generate a trigger signal; The processor first calculates the current change rate based on the first current and the second current; then, based on the trigger signal, it determines whether the current change rate is less than a first threshold. If the current change rate is less than the first threshold, an alarm signal is generated; finally, based on the alarm signal, it determines whether the closing and opening of the disconnecting switch unit are qualified. The processor further includes: firstly, calculating the three-phase current imbalance rate based on the second current; then determining whether the three-phase current imbalance rate exceeds a second threshold; if the three-phase current imbalance rate exceeds the second threshold, generating an alarm signal; and finally determining whether the closing and opening of the disconnecting switch unit are qualified based on the alarm signal. The disconnecting switch unit includes a circuit breaker, a first main disconnect switch, a second main disconnect switch, a first grounding disconnect switch, a second grounding disconnect switch, and a third grounding disconnect switch; The first main disconnect switch receives a first current at its input terminal and its output terminal is connected to the input terminal of the circuit breaker. One end of the first grounding switch is connected between the output terminal of the first main switch and the input terminal of the circuit breaker, and the other end of the first grounding switch is connected to the ground. The output terminal of the circuit breaker is connected to the input terminal of the second main disconnect switch; One end of the second grounding switch is connected between the output terminal of the circuit breaker and the input terminal of the second main switch, and the other end of the second grounding switch is connected to the ground. One end of the third grounding switch is connected between the output end of the second main switch and the ground end, and the other end of the second grounding switch is connected to the ground end; The current transformer unit includes a first current transformer, a second current transformer, and a third current transformer; One end of the first current transformer is connected between the first grounding switch and the ground terminal, and the other end of the first current transformer is connected to the first input terminal of the processor. One end of the second current transformer is connected between the second grounding switch and the ground terminal, and the other end of the second current transformer is connected to the second input terminal of the processor. One end of the third current transformer is connected between the third grounding switch and the ground terminal, and the other end of the third current transformer is connected to the third input terminal of the processor.

2. The GIS equipment disconnect switch operation status detector according to claim 1, characterized in that, The first current transformer, the second current transformer, and the third current transformer are ZLB-C61-SP1 type closed-loop zero-flux AC leakage current sensors.

3. A GIS equipment disconnect switch operation status detector according to claim 1, characterized in that, The processor includes an AD converter and a microcontroller; The input terminal of the AD converter is connected to the output terminal of the current transformer unit, and the output terminal of the AD converter is connected to the input terminal of the microcontroller. The microcontroller outputs the detection result; the detection result is used to indicate whether the closing and opening of the disconnecting switch unit are qualified.

4. A GIS equipment disconnect switch operation status detector according to claim 3, characterized in that, The microcontroller is an STC12C5A60S2 microcontroller.

5. A GIS equipment disconnect switch operation status detector according to claim 3, characterized in that, The AD converter is an HT7038 chip.

6. A method for detecting the operational status of a disconnector switch in a GIS device, comprising connecting a disconnector switch operational status detector to a disconnector switch unit, characterized in that, The disconnector switch operation status detector includes a current transformer and a processor. The detection method includes first calculating the current change rate based on a first current obtained from the disconnector switch unit and a second current obtained from the current transformer; then determining whether the current change rate is less than a first threshold based on a trigger signal generated by the current transformer unit; if the current change rate is less than the first threshold, an alarm signal is generated; finally, determining whether the closing and opening of the disconnector switch are qualified based on the alarm signal. The detection method also includes calculating the three-phase current imbalance rate based on the second current; then determining whether the three-phase current imbalance rate exceeds a second threshold; if the three-phase current imbalance rate exceeds the second threshold, an alarm signal is generated; finally, determining whether the closing and opening of the disconnector switch unit are qualified based on the alarm signal.

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