Device and method for detecting electric contact state of GIS (Gas Insulated Switchgear) equipment contact

Abstract

The invention discloses a GIS equipment contact electric contact state detection device and method, an FPGA control module generates a repetition frequency pulse large current control signal according to element data of a GIS equipment contact to be detected, an IGBT group controls a battery pack to generate repetition frequency pulse large current according to the control signal, and the FPGA control module controls the battery pack to generate the repetition frequency pulse large current according to a time domain voltage value of a diverter. And calculating the time-domain current value of the test loop according to the time-domain voltage value of the to-be-tested contact, calculating the time-domain contact resistance value of the to-be-tested contact, and further determining the electric contact state of the to-be-tested contact, so that the test environment of the to-be-tested contact is close to the actual high-current operation environment, and the detection accuracy of the electric contact state of the to-be-tested contact is improved. The problem that in the prior art, only the contact resistance change of the contact under the low test current level can be detected, and the contact resistance change of the GIS equipment contact under the large current change cannot be detected, so that the detection accuracy of the electric contact state of the GIS equipment contact is low is solved.

Description

Technical Field

[0001] The present invention relates to the field of electrical contact state detection, and in particular to a device and method for detecting the electrical contact state of a contact of a GIS device. Background Art

[0002] Gas Insulated Switchgear (GIS) or SF6 fully enclosed insulated switchgear plays a pivotal role in the power transmission and transformation system. The main circuit resistance of GIS is composed of the contact resistance between the moving and static contacts, the contact resistance at the connection between the conductive rod and the contact, and the conductive rod resistance. When the electrical contact state of the GIS equipment is abnormal, the contact resistance of the GIS equipment will increase, causing the temperature of the contact element of the GIS equipment to increase, resulting in contact element transmission failure, and ultimately affecting the safety of the power system due to GIS equipment failure. Therefore, accurately detecting the electrical contact state of the contact of the GIS equipment is an important aspect of maintaining the safety of the power system.

[0003] At present, DC loop resistance measurement is the most widely used method to directly evaluate the contact condition of contacts. However, since this method uses a test current of 100A to 200A for measurement, there is a large gap between this method and the rated operating current of common typical GIS equipment (such as LW24-252, with a rated voltage of 252kV and a rated current of 3150A). That is, this method can only detect the contact resistance change of the contact at a lower test current level, but cannot detect the contact resistance change of the GIS equipment contact under a larger current change, which leads to the inability to accurately detect the electrical contact state of the GIS equipment contact. Summary of the invention

[0004] The present invention provides a device and method for detecting the electrical contact status of contacts of GIS equipment, which can solve the problem that the prior art can only detect the contact resistance change of the contacts under a lower test current level, but cannot detect the contact resistance change of the GIS equipment contacts under a larger current change, thereby resulting in the inability to accurately detect the electrical contact status of the GIS equipment contacts.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides an electrical contact state detection device for GIS equipment contacts, comprising: a battery pack, a shunt, an IGBT group and an FPGA control module; wherein the battery pack, the shunt, the IGBT group and the contact to be tested of the GIS equipment form a test main circuit; the common collector of the IGBT group is connected to the positive electrode of the battery pack, the common emitter of the IGBT group is connected to the upper electrode of the contact to be tested, the lower electrode of the contact to be tested is connected to an electrode at one end of the shunt, and the electrode at the other end of the shunt is connected to the negative electrode of the battery pack;

[0006] The FPGA control module is used to generate a high-frequency pulse current control signal according to the component data of the contact to be tested, and send it to the IGBT group;

[0007] The IGBT group is used to control the battery group to generate a heavy-frequency pulse high current according to the heavy-frequency pulse high current control signal;

[0008] The shunt is used to measure the time domain voltage value of the shunt under a high-frequency pulse current;

[0009] The FPGA control module is also used to calculate the time domain current value of the test loop under the repetitive pulse high current according to the time domain voltage value of the shunt under the repetitive pulse high current;

[0010] According to the time domain current value of the test circuit under the high frequency pulse current and the time domain voltage value of the contact to be tested, the time domain contact resistance value of the contact to be tested under the high frequency pulse current is calculated;

[0011] The electrical contact state of the contact to be tested is determined according to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current.

[0012] Furthermore, the FPGA control module is used to generate a high-frequency pulse current control signal according to the component data of the contact to be tested, including:

[0013] The FPGA control module is used to determine the pulse number, pulse width and pulse interval of the repetitive pulse high current control signal according to the component data of the contact to be tested, and send the repetitive pulse high current control signal to the IGBT master-slave driver of the IGBT group.

[0014] Furthermore, the IGBT group is used to control the battery group to generate a high-frequency pulse current according to the high-frequency pulse current control signal, including:

[0015] The IGBT group is used to receive the re-frequency pulse high current control signal sent by the FPGA control module through the IGBT master-slave drive of the IGBT group, so that the IGBT master-slave drive generates a gate drive signal according to the re-frequency pulse high current control signal, and then the IGBT group controls the battery group to generate a re-frequency pulse high current according to the gate drive signal.

[0016] Further, the FPGA control module includes: an FPGA chip, an A / D converter, an instrumentation amplifier and a differential amplifier;

[0017] The FPGA chip is used to generate a high-frequency pulse current control signal according to the component data of the contact to be tested, and send it to the IGBT group, so that the IGBT group controls the battery group to generate a high-frequency pulse current according to the high-frequency pulse current control signal;

[0018] The instrument amplifier is used to obtain the time domain voltage value of the shunt and the time domain voltage value of the contact to be tested under the repetitive frequency pulse large current, and to perform multiple gain on the time domain voltage value of the shunt and the contact to be tested under the repetitive frequency pulse large current according to the gain multiple of the instrument amplifier to obtain the time domain voltage value of the shunt and the time domain voltage value of the contact to be tested after gain, and send the time domain voltage value of the shunt and the time domain voltage value of the contact to be tested after gain to the A / D converter;

[0019] The differential amplifier is used to obtain the voltage value of the battery pack, and adjust the voltage value of the battery pack according to the differential amplification factor of the differential amplifier to obtain the adjusted voltage value of the battery pack, and send the adjusted voltage value of the battery pack to the A / D converter;

[0020] The A / D converter is used to convert the adjusted battery pack voltage value, the time domain voltage value of the shunt after gain, and the time domain voltage value of the contact to be tested into digital signals, and send them to the FPGA chip;

[0021] The FPGA chip is also used to calculate the time domain current value of the test circuit under the repetitive pulse high current based on the time domain voltage value of the shunt after gain, and to calculate the time domain contact resistance value of the contact to be tested under the repetitive pulse high current based on the time domain current value of the test circuit under the repetitive pulse high current and the time domain voltage value of the contact to be tested.

[0022] Furthermore, the FPGA control module further includes: a battery pack power control unit;

[0023] The battery pack power control unit is used to control the voltage of the battery pack and supply power to the FPGA control module.

[0024] Furthermore, the electrical contact state detection device for GIS equipment contacts further includes: a display module;

[0025] The display module is used to generate a time domain change curve of the contact resistance of the contact to be tested according to the time domain contact resistance value of the contact to be tested under a high-frequency pulse current;

[0026] The display module is also used to send control instructions to the FPGA control module.

[0027] Furthermore, the diverter further includes: a diverter heat dissipation module;

[0028] The diverter heat dissipation module is used to adjust the temperature of the diverter.

[0029] Based on the above device embodiment, the present invention provides a method embodiment;

[0030] An embodiment of the present invention provides a method for detecting the electrical contact state of a GIS device contact, which is applicable to an FPGA control module of an electrical contact state detection device for a GIS device contact; the contact state detection device also includes a battery pack, a shunt and an IGBT group; the battery pack, the shunt, the IGBT group and the contact to be tested of the GIS device form a test main circuit; the common collector of the IGBT group is connected to the positive electrode of the battery pack, the common emitter of the IGBT group is connected to the upper electrode of the contact to be tested, the lower electrode of the contact to be tested is connected to an electrode at one end of the shunt, and the electrode at the other end of the shunt is connected to the negative electrode of the battery pack;

[0031] The method for detecting the electrical contact state of a GIS equipment contact comprises:

[0032] Generate a high-frequency pulse current control signal according to the component data of the contact to be tested, and send it to the IGBT group, so that the IGBT group is used to control the battery group to generate a high-frequency pulse current according to the high-frequency pulse current control signal;

[0033] According to the time domain voltage value of the shunt under the high frequency pulse current, calculate the time domain current value of the test loop under the high frequency pulse current;

[0034] According to the time domain current value of the test circuit under the high frequency pulse current and the time domain voltage value of the contact to be tested, the time domain contact resistance value of the contact to be tested under the high frequency pulse current is calculated;

[0035] The electrical contact state of the contact to be tested is determined according to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current.

[0036] Further, the generating of a repetitive pulse current control signal according to the component data of the contact to be tested, and sending it to the IGBT group, so that the IGBT group is used to control the battery group to generate a repetitive pulse current according to the repetitive pulse current control signal, includes:

[0037] According to the component data of the contact to be tested, the pulse number, pulse width and pulse interval of the heavy-frequency pulse high-current control signal are determined;

[0038] The repetitive pulse high current control signal is sent to the IGBT master-slave driver of the IGBT group, so that the IGBT master-slave driver generates a gate drive signal according to the repetitive pulse high current control signal, and then the IGBT group controls the battery group to generate a repetitive pulse high current according to the gate drive signal.

[0039] Furthermore, the method of determining the electrical contact state of the contact to be tested according to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current also includes:

[0040] According to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current, a time domain change curve of the contact resistance of the contact to be tested under the high-frequency pulse current is generated;

[0041] The electrical contact state of the contact to be tested is determined according to the contact resistance time domain variation curve of the contact to be tested under the high-frequency pulse current.

[0042] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0043] The present invention generates a high-frequency pulse current control signal according to the component data of the contact to be tested through an FPGA control module, and sends it to the IGBT group. The IGBT group receives the high-frequency pulse current control signal to control the battery group to generate a high-frequency pulse current of the test loop, and calculates the time-domain current value of the test loop according to the time-domain voltage value of the shunt in the test loop under the high-frequency pulse current through the FPGA integrated module. The time-domain contact resistance value of the contact to be tested under the high-frequency pulse current is calculated according to the time-domain current value of the test loop and the time-domain voltage value of the contact to be tested. Finally, the time-domain current value of the contact to be tested under the high-frequency pulse current is calculated according to the time-domain current value of the test loop and the time-domain voltage value of the contact to be tested. The contact resistance value is used to determine the electrical contact state of the contact to be tested. That is, the present invention generates a test condition of a high-frequency pulse current to make the test environment of the contact to be tested of the GIS device close to the actual high-current power environment, thereby detecting the contact resistance change of the contact to be tested of the GIS device under a large current change, thereby improving the accuracy of the electrical contact state detection of the contact of the GIS device, and solving the problem that the prior art can only detect the contact resistance change of the contact under a lower test current level, but cannot detect the contact resistance change of the contact of the GIS device under a large current change, thereby failing to accurately detect the electrical contact state of the contact of the GIS device. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 : A device structure diagram of a device for detecting the electrical contact state of a GIS equipment contact provided by an embodiment of the present invention;

[0045] Figure 2 : A flow chart of the steps of a method for detecting the electrical contact state of a GIS equipment contact provided by an embodiment of the present invention;

[0046] Figure 3 : A typical current output waveform diagram of a single operation and a repetitive frequency operation of an electrical contact state detection device for a GIS equipment contact under a repetitive frequency pulse high current provided by an embodiment of the present invention;

[0047] Figure 4 :It is the calibration result of the electrical contact state detection device of a GIS equipment contact on a standard 150μΩ shunt of the present invention;

[0048] Figure 5, is a diagram showing the measurement results of contact resistance in one embodiment of the present invention;

[0049] Figure 6 , is another measurement result diagram of contact resistance in one embodiment of the present invention;

[0050] Figure 7 , is another measurement result diagram of the contact resistance in one embodiment of the present invention. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] In the description of the present invention, it should be understood that the term "first" is only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0053] Embodiment 1:

[0054] Reference Figure 1 , is a device structure diagram of an electrical contact state detection device for a GIS equipment contact provided by an embodiment of the present invention, the device, comprising: a battery pack, a shunt, an IGBT group and an FPGA control module; wherein the battery pack, the shunt, the IGBT group and the contact to be tested of the GIS equipment form a test main circuit; the common collector of the IGBT group is connected to the positive electrode of the battery pack, the common emitter of the IGBT group is connected to the upper electrode of the contact to be tested, the lower electrode of the contact to be tested is connected to an electrode at one end of the shunt, and the electrode at the other end of the shunt is connected to the negative electrode of the battery pack;

[0055] The FPGA control module is used to generate a high-frequency pulse current control signal according to the component data of the contact to be tested, and send it to the IGBT group;

[0056] In this embodiment, the FPGA control module is used to determine the pulse number, pulse width and pulse interval of the repetitive pulse high current control signal according to the component data of the contact to be tested, and send the repetitive pulse high current control signal to the IGBT master-slave driver of the IGBT group; wherein, referring to Figure 3 , which is a typical current output waveform diagram of a single operation and a repetitive frequency operation of an electrical contact state detection device for a GIS equipment contact under a repetitive frequency pulse large current provided by an embodiment of the present invention, Figure 3 Figure a in the middle is a typical current output waveform of a single operation of the detection device. Figure 3Figure b in the middle is a typical current output waveform diagram of the repetitive operation of the detection device. The number of pulses can be set to be adjustable from 1 to 9, in steps of 1; the pulse width can be set to be adjustable from 100ms to 1000ms, in steps of 50ms; the pulse width can be set to be adjustable from 100ms to 4000ms, in steps of 50ms.

[0057] The IGBT group is used to control the battery group to generate a heavy-frequency pulse high current according to the heavy-frequency pulse high current control signal;

[0058] In this embodiment, the IGBT group is used to receive the repetitive pulse high current control signal sent by the FPGA control module through the IGBT master-slave drive of the IGBT group, so that the IGBT master-slave drive generates a gate drive signal according to the repetitive pulse high current control signal, and then the IGBT group controls the battery group to generate a repetitive pulse high current according to the gate drive signal; wherein, the battery group can choose to use a group of 6 3.2V / 202AH large-capacity lithium iron phosphate batteries connected in series as a battery group; the voltage of the battery group is between 18.6V and 21.3V, and when the voltage of the battery group is lower than 19.2V, it is charged by connecting the mains to the charging power supply; the IGBT group can choose to use two 3600A large-capacity IGBTs in parallel to form an IGBT group; the IGBT master-slave drive of the IGBT group can be composed of a master driver and a slave driver; the battery group composed of large-capacity lithium iron phosphate batteries and the IGBT group can realize repetitive pulse square wave discharge.

[0059] The shunt is used to measure the time domain voltage value of the shunt under a high-frequency pulse current;

[0060] In this embodiment, the shunt can be a shunt with a resistance of 75μΩ, which can be used to detect the time domain voltage value of the shunt under a high-frequency pulse current, and then provide the time domain voltage value of the shunt for measuring the time domain current value of the test main loop.

[0061] The FPGA control module is also used to calculate the time domain current value of the test loop under the repetitive pulse high current according to the time domain voltage value of the shunt under the repetitive pulse high current;

[0062] According to the time domain current value of the test circuit under the high frequency pulse current and the time domain voltage value of the contact to be tested, the time domain contact resistance value of the contact to be tested under the high frequency pulse current is calculated;

[0063] The electrical contact state of the contact to be tested is determined according to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current.

[0064] In this embodiment, by changing the test conditions of the contact to be tested under high-frequency pulse current, the contact resistance variation trend of the contact to be tested under different test conditions can be obtained, thereby determining the electrical contact state of the contact to be tested.

[0065] In this embodiment, the FPGA control module includes: an FPGA chip, an A / D converter, an instrument amplifier and a differential amplifier; wherein the FPGA chip includes but is not limited to the EP4CE10 model; the A / D converter includes but is not limited to the AD7606 model; the instrument amplifier includes but is not limited to the AD8250ARMZ model; the differential amplifier includes but is not limited to the INA143 model;

[0066] The FPGA chip is used to generate a high-frequency pulse current control signal according to the component data of the contact to be tested, and send it to the IGBT group, so that the IGBT group controls the battery group to generate a high-frequency pulse current according to the high-frequency pulse current control signal;

[0067] The instrument amplifier is used to obtain the time domain voltage value of the shunt and the time domain voltage value of the contact to be tested under the repetitive frequency pulse large current, and to perform multiple gain on the time domain voltage value of the shunt and the contact to be tested under the repetitive frequency pulse large current according to the gain multiple of the instrument amplifier to obtain the time domain voltage value of the shunt and the time domain voltage value of the contact to be tested after gain, and send the time domain voltage value of the shunt and the time domain voltage value of the contact to be tested after gain to the A / D converter;

[0068] In this embodiment, the gain multiple of the instrument amplifier is set according to the resistance range of the contact to be measured. The gain multiple of the instrument amplifier can be set to 1 or 10. When the resistance range of the contact to be measured is between 0μΩ and 250μΩ, the gain multiple of the instrument amplifier is set to 10. When the resistance range of the contact to be measured is between 250μΩ and 2500μΩ, the gain multiple of the instrument amplifier is set to 1 to improve the signal-to-noise ratio of the contact voltage. The resistance range of the contact to be measured can refer to the factory specified value of the manufacturer of the contact to be measured.

[0069] The differential amplifier is used to obtain the voltage value of the battery pack, and adjust the voltage value of the battery pack according to the differential amplification factor of the differential amplifier to obtain the adjusted voltage value of the battery pack, and send the adjusted voltage value of the battery pack to the A / D converter;

[0070] In this embodiment, the differential gain of the differential amplifier is set according to the input analog signal voltage range of the A / D converter. The differential gain of the differential amplifier is set to 0.1 times, which is used to reduce the battery pack voltage by 10 times to meet the input analog signal voltage range of the A / D converter.

[0071] The A / D converter is used to convert the adjusted battery pack voltage value, the time domain voltage value of the shunt after gain, and the time domain voltage value of the contact to be tested into digital signals, and send them to the FPGA chip;

[0072] The FPGA chip is also used to calculate the time domain current value of the test circuit under the repetitive pulse high current based on the time domain voltage value of the shunt after gain, and to calculate the time domain contact resistance value of the contact to be tested under the repetitive pulse high current based on the time domain current value of the test circuit under the repetitive pulse high current and the time domain voltage value of the contact to be tested.

[0073] In this embodiment, the FPGA control module further includes: a battery pack power control unit;

[0074] The battery pack power control unit is used to control the voltage of the battery pack and supply power to the FPGA control module.

[0075] In this embodiment, the battery pack power control unit converts the battery pack voltage into 5V, 3.3V, 15V, -15V control voltages and 12V cooling fan drive voltage. The battery pack power control unit also integrates a Type-C power supply circuit to power the FPGA control module through a Type-C power line.

[0076] In this embodiment, a device for detecting the electrical contact state of a contact of a GIS device further includes: a display module; wherein the display module may be composed of an LCD touch screen and a control device;

[0077] The display module is used to generate a time domain change curve of the contact resistance of the contact to be tested according to the time domain contact resistance value of the contact to be tested under a high-frequency pulse current;

[0078] The display module is also used to send control instructions to the FPGA control module.

[0079] In this embodiment, the diverter further includes: a diverter heat dissipation module;

[0080] The diverter heat dissipation module is used to adjust the temperature of the diverter.

[0081] In this embodiment, a device for detecting the electrical contact status of a contact of a GIS device further includes: a USB storage device; the USB storage device is used to store detection data.

[0082] Embodiment 2:

[0083] Reference Figure 2, is a flowchart of the steps of a method for detecting the electrical contact state of a GIS device contact provided by an embodiment of the present invention, the method is applicable to an FPGA control module of an electrical contact state detection device for a GIS device contact; the contact state detection device also includes a battery pack, a shunt and an IGBT group; the battery pack, the shunt, the IGBT group and the contact to be tested of the GIS device form a test main circuit; the common collector of the IGBT group is connected to the positive electrode of the battery pack, the common emitter of the IGBT group is connected to the upper electrode of the contact to be tested, the lower electrode of the contact to be tested is connected to an electrode at one end of the shunt, and the electrode at the other end of the shunt is connected to the negative electrode of the battery pack;

[0084] At least the following steps are included:

[0085] Step S1: generating a high-frequency pulse current control signal according to the component data of the contact to be tested, and sending it to the IGBT group, so that the IGBT group is used to control the battery group to generate a high-frequency pulse current according to the high-frequency pulse current control signal;

[0086] Step S2: Calculate the time domain current value of the test loop under the high frequency pulse current according to the time domain voltage value of the shunt under the high frequency pulse current;

[0087] Step S3: Calculate the time domain contact resistance value of the contact to be tested under the high frequency pulse current according to the time domain current value of the test loop and the time domain voltage value of the contact to be tested under the high frequency pulse current;

[0088] Step S4: determining the electrical contact state of the contact to be tested according to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current.

[0089] In this embodiment, the generating of the repetitive pulse current control signal according to the component data of the contact to be tested and sending it to the IGBT group so that the IGBT group is used to control the battery group to generate the repetitive pulse current according to the repetitive pulse current control signal includes:

[0090] According to the component data of the contact to be tested, the pulse number, pulse width and pulse interval of the heavy-frequency pulse high-current control signal are determined;

[0091] The repetitive pulse high current control signal is sent to the IGBT master-slave driver of the IGBT group, so that the IGBT master-slave driver generates a gate drive signal according to the repetitive pulse high current control signal, and then the IGBT group controls the battery group to generate a repetitive pulse high current according to the gate drive signal.

[0092] In this embodiment, the step of determining the electrical contact state of the contact to be tested according to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current further includes:

[0093] According to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current, a time domain change curve of the contact resistance of the contact to be tested under the high-frequency pulse current is generated;

[0094] The electrical contact state of the contact to be tested is determined according to the contact resistance time domain variation curve of the contact to be tested under the high-frequency pulse current.

[0095] Embodiment 3:

[0096] Reference Figure 4 , is the calibration result of the electrical contact state detection device of a GIS equipment contact on a standard 150μΩ shunt of the present invention. The present invention selects a standard 150μΩ shunt as a calibration resistor for calibration test. The results are as follows Figure 4 As shown, the resistance measurement value read when stable is about 149.6μΩ, and the test current reaches more than 3000A.

[0097] Reference Figure 5 , Figure 6 and Figure 7 , respectively, are different measurement result diagrams of contact resistance in an embodiment of the present invention, specifically, a GIS equipment contact electrical contact state detection device provided by the present invention, in which only a single spring is used to contact and simulate spring aging, and the contact resistance of the contact under different test conditions of DC circuit method, single / repetitive frequency pulse, and changing pulse interval is measured. First, a 300A DC circuit resistance test is performed on the 4-meter-long tube mother and the contact when a single spring is in contact. When there is a single spring, the DC circuit resistance test result is 22μΩ, and then the device of the present invention is used to set the number of pulses to 1 and the pulse width to 100ms, and a single pulse measurement is performed. The results are as follows Figure 5 As shown in the figure, a device for detecting the electrical contact state of a GIS equipment contact of the present invention uses only a single spring contact to simulate spring aging under the DC loop method and single-frequency pulse test conditions. The value of the relatively stable part is about 14.4μΩ. Compared with the DC test result, the pulse current method test value is significantly smaller, which may be due to the large current causing the oxide film at the contact point to break down, increasing the contact area, thereby reducing the contact resistance.

[0098] Figure 6 and Figure 7 This is a repetitive pulse test. The repetitive test sets the pulse width to 200ms, the pulse interval to 200ms, the number of pulses to 5, and the pulses to be triggered 5 times, generating a total of 25 pulse currents. Two groups of experiments were set up, and the time intervals of the trigger pulses in each group of experiments were 5s and 2s respectively, reducing the heat dissipation time to simulate the contact state at different temperature increases. The experimental data of the last 5 pulse currents were recorded.

[0099] The experimental results of the trigger pulse interval of 5s are as follows Figure 6 As shown in the figure, a contact state detection device for GIS equipment contacts of the present invention is used in combination with a 4-meter-long tube mother and a contact, and only a single spring is used to contact to simulate spring aging, and the interval between repetitive pulses and trigger pulses is 5s. The contact resistance measurement result is about 14μΩ when the single spring is contacted and tested at an interval of 5s. The contact resistance is reduced compared with the single pulse resistance value due to the heat deposition caused by the repeated pulses at the repetitive frequency. However, since the interval between the trigger pulses is still relatively long, the contact is able to dissipate heat between each repetitive pulse action, and the contact resistance changes relatively stably with the increase in the number of pulse emissions.

[0100] The experimental results of the trigger pulse interval of 2s are as follows Figure 7 As shown, a contact state detection device for GIS equipment contacts of the present invention is a contact state detection device for GIS equipment contacts. In the combination of a 4-meter-long tube mother and a contact, only a single spring is used to contact and simulate spring aging, and the interval between repetitive pulses and trigger pulses is 2s. The contact resistance measurement value gradually decreases with the increase of the number of pulse emissions, and is finally about 7.7μΩ, indicating that as the trigger pulse interval is shortened from 5s to 2s, the heat dissipation of the contact is smaller between each repetitive pulse action, and the thermal effect of the current is more significant, resulting in local melting of the contact point, increasing the contact area between the spring contact finger and the busbar, and further reducing the contact resistance value. Finally, the contact resistance time domain change curve shows a decrease with the increase of the pulse emission frequency, that is, the contact resistance change trend under the influence of melting.

[0101] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A device for detecting the electrical contact state of a GIS equipment contact, characterized in that: include: A battery pack, a shunt, an IGBT group and an FPGA control module; wherein the battery pack, the shunt, the IGBT group and the contact to be tested of the GIS device form a test main circuit; the common collector of the IGBT group is connected to the positive electrode of the battery pack, the common emitter of the IGBT group is connected to the upper electrode of the contact to be tested, the lower electrode of the contact to be tested is connected to an electrode at one end of the shunt, and the electrode at the other end of the shunt is connected to the negative electrode of the battery pack; The FPGA control module is used to generate a high-frequency pulse current control signal according to the component data of the contact to be tested, and send it to the IGBT group; The IGBT group is used to control the battery group to generate a heavy-frequency pulse high current according to the heavy-frequency pulse high current control signal; The shunt is used to measure the time domain voltage value of the shunt under a high-frequency pulse current; The FPGA control module is also used to calculate the time domain current value of the test loop under the repetitive pulse high current according to the time domain voltage value of the shunt under the repetitive pulse high current; According to the time domain current value of the test circuit under the high frequency pulse current and the time domain voltage value of the contact to be tested, the time domain contact resistance value of the contact to be tested under the high frequency pulse current is calculated; The electrical contact state of the contact to be tested is determined according to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current.

2. The electrical contact state detection device for GIS equipment contacts according to claim 1, characterized in that: The FPGA control module is used to generate a high-frequency pulse current control signal according to the component data of the contact to be tested, including: The FPGA control module is used to determine the pulse number, pulse width and pulse interval of the repetitive pulse high current control signal according to the component data of the contact to be tested, and send the repetitive pulse high current control signal to the IGBT master-slave driver of the IGBT group.

3. The electrical contact state detection device for GIS equipment contacts according to claim 2, characterized in that: The IGBT group is used to control the battery group to generate a heavy-frequency pulse high current according to the heavy-frequency pulse high current control signal, including: The IGBT group is used to receive the repetitive pulse high current control signal sent by the FPGA control module through the IGBT master-slave drive of the IGBT group, so that the IGBT master-slave drive generates a gate drive signal according to the repetitive pulse high current control signal, and then the IGBT group controls the battery group to generate a repetitive pulse high current according to the gate drive signal.

4. The electrical contact state detection device for GIS equipment contacts according to claim 3 is characterized in that: The FPGA control module includes: an FPGA chip, an A / D converter, an instrument amplifier and a differential amplifier; The FPGA chip is used to generate a high-frequency pulse current control signal according to the component data of the contact to be tested, and send it to the IGBT group, so that the IGBT group controls the battery group to generate a high-frequency pulse current according to the high-frequency pulse current control signal; The instrument amplifier is used to obtain the time domain voltage value of the shunt and the time domain voltage value of the contact to be tested under the repetitive frequency pulse large current, and to perform multiple gain on the time domain voltage value of the shunt and the contact to be tested under the repetitive frequency pulse large current according to the gain multiple of the instrument amplifier to obtain the time domain voltage value of the shunt and the time domain voltage value of the contact to be tested after gain, and send the time domain voltage value of the shunt and the time domain voltage value of the contact to be tested after gain to the A / D converter; The differential amplifier is used to obtain the voltage value of the battery pack, and adjust the voltage value of the battery pack according to the differential amplification factor of the differential amplifier to obtain an adjusted voltage value of the battery pack, and send the adjusted voltage value of the battery pack to the A / D converter; The A / D converter is used to convert the adjusted battery pack voltage value, the shunt time domain voltage value after gain and the contact time domain voltage value to be tested into digital signals and send them to the FPGA chip; The FPGA chip is also used to calculate the time domain current value of the test circuit under the repetitive pulse high current based on the time domain voltage value of the shunt after gain, and to calculate the time domain contact resistance value of the contact to be tested under the repetitive pulse high current based on the time domain current value of the test circuit under the repetitive pulse high current and the time domain voltage value of the contact to be tested.

5. The electrical contact state detection device for GIS equipment contacts according to claim 4, characterized in that: The FPGA control module further includes: a battery pack power control unit; The battery pack power control unit is used to control the voltage of the battery pack and supply power to the FPGA control module.

6. The electrical contact state detection device for GIS equipment contacts according to claim 5, characterized in that: Also includes: Display module; The display module is used to generate a time domain change curve of the contact resistance of the contact to be tested according to the time domain contact resistance value of the contact to be tested under a high-frequency pulse current; The display module is also used to send control instructions to the FPGA control module.

7. The electrical contact state detection device for GIS equipment contacts according to claim 6, characterized in that: The diverter also includes: a diverter heat dissipation module; The diverter heat dissipation module is used to adjust the temperature of the diverter.

8. A method for detecting the electrical contact state of a GIS equipment contact, characterized in that: An FPGA control module for an electrical contact state detection device for a GIS equipment contact; the contact state detection device also includes a battery pack, a shunt and an IGBT group; the battery pack, the shunt, the IGBT group and the contact to be tested of the GIS equipment form a test main circuit; the common collector of the IGBT group is connected to the positive electrode of the battery pack, the common emitter of the IGBT group is connected to the upper electrode of the contact to be tested, the lower electrode of the contact to be tested is connected to an electrode at one end of the shunt, and the electrode at the other end of the shunt is connected to the negative electrode of the battery pack; The method for detecting the electrical contact state of a GIS equipment contact comprises: Generate a high-frequency pulse current control signal according to the component data of the contact to be tested, and send it to the IGBT group, so that the IGBT group is used to control the battery group to generate a high-frequency pulse current according to the high-frequency pulse current control signal; According to the time domain voltage value of the shunt under the high frequency pulse current, calculate the time domain current value of the test loop under the high frequency pulse current; According to the time domain current value of the test circuit under the high frequency pulse current and the time domain voltage value of the contact to be tested, the time domain contact resistance value of the contact to be tested under the high frequency pulse current is calculated; The electrical contact state of the contact to be tested is determined according to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current.

9. A method for detecting the electrical contact state of a GIS equipment contact according to claim 8, characterized in that: The method of generating a repetitive pulse current control signal according to the component data of the contact to be tested and sending the signal to the IGBT group so that the IGBT group is used to control the battery group to generate a repetitive pulse current according to the repetitive pulse current control signal comprises: According to the component data of the contact to be tested, the pulse number, pulse width and pulse interval of the heavy-frequency pulse high-current control signal are determined; The repetitive pulse high current control signal is sent to the IGBT master-slave driver of the IGBT group, so that the IGBT master-slave driver generates a gate drive signal according to the repetitive pulse high current control signal, and then the IGBT group controls the battery group to generate a repetitive pulse high current according to the gate drive signal.

10. A method for detecting the electrical contact state of a GIS equipment contact according to claim 9, characterized in that: The method of determining the electrical contact state of the contact to be tested according to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current also includes: According to the time domain contact resistance value of the contact to be tested under the high-frequency pulse current, a time domain change curve of the contact resistance of the contact to be tested under the high-frequency pulse current is generated; The electrical contact state of the contact to be tested is determined according to the contact resistance time domain variation curve of the contact to be tested under the high-frequency pulse current.

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