A kind of insulator test system and method of synchronous analog high voltage large current

Abstract

This invention discloses a synchronous simulation system and method for testing insulators under high voltage and high current. The insulator testing system includes a high current generating device, an energy harvesting transformer, an insulating support, a high-frequency power conversion device, an AC power supply, a grounding metal support, a load, and a data acquisition and processing device. This insulator testing system can simultaneously provide the high voltage required for withstand voltage testing and the high current required for wireless power transmission; it controls the sequence of high voltage and high current excitation to measure various insulator parameters; and it controls the triggering sequence of high voltage and high current to achieve synchronous control of high current generation and efficiency testing. This invention enables withstand voltage testing of multi-stage coil high-voltage insulators by providing high voltage through an AC power supply, and controls the triggering sequence of high voltage and high current to test the transmission efficiency of multi-stage coil high-voltage insulators during short-term high current occurrences.

Description

Technical Field

[0001] This invention relates to the field of high-voltage power technology, specifically to an insulator testing system and method for synchronously simulating high-voltage and high-current conditions. Background Technology

[0002] Online monitoring devices are an effective measure to ensure the safe and reliable operation of transmission lines. However, due to the wide distribution and long distances of transmission lines, the power supply problem for online monitoring devices is difficult to solve effectively. Photovoltaic power supply is the mainstream power supply method among existing online monitoring equipment for transmission lines, but the effectiveness of photovoltaic power supply is severely limited by local climate conditions. In addition, it also suffers from problems such as large device size, frequent battery replacement, high maintenance costs, and susceptibility to damage under severe weather conditions. Data from actual engineering applications show that a large number of photovoltaic power supply devices are damaged every year due to severe weather.

[0003] To address the aforementioned issues, scholars both domestically and internationally have proposed numerous novel power supply methods. Among them, magnetic resonant coupling wireless power transmission is currently the most mature and practical method. Especially given the existing research foundation for multi-coil wireless power transmission, the advantages of wireless power transmission based on multi-stage coil high-voltage insulators are even more pronounced. In this method, the electrical energy supplied to the equipment comes directly from the transmission line; simultaneously, the use of multi-stage magnetic resonant coupling avoids the insulation problems between high-voltage transmission lines and low-voltage equipment.

[0004] For the application of multi-stage coil high-voltage insulators, the transmission power, efficiency, and withstand voltage performance of the insulators must first be tested. Testing the insulators in real-world applications would incur significant costs, impact transmission lines, and, most importantly, compromise the safety and stability of the experiment. Since multi-stage coil high-voltage insulators extract energy from transmission lines in actual operation, and laboratory conditions generally cannot simultaneously meet the testing requirements of high current and high voltage, finding a way to simultaneously meet the testing conditions of high current and high voltage for multi-stage coil high-voltage insulators under experimental conditions has become a pressing technical problem. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a synchronous simulation of high voltage and high current insulator testing system and method, which can realize laboratory testing of the withstand voltage characteristics and wireless power transmission of multi-stage coil high voltage insulators.

[0006] In view of this, the present invention provides a synchronous simulation of high voltage and high current insulator testing system, including a high current generating device, an energy harvesting transformer, an insulating support, a high frequency power conversion device, an AC power supply, a grounding metal support, a load, and a data acquisition and processing device.

[0007] An insulating bracket supports the energy harvesting transformer, which is installed in the series circuit of the high-current generator. The output terminal of the energy harvesting transformer is directly connected to the input terminal of the high-frequency power conversion device. The high-voltage end of the multi-stage coil high-voltage insulator under test is equipped with an equalizing ring, and the output terminal of the high-frequency power conversion device is connected to the high-voltage end of the multi-stage coil high-voltage insulator under test. The high-current generator is used to apply a large current to the multi-stage coil high-voltage insulator under test through the energy harvesting transformer and the high-frequency power conversion device.

[0008] One end of the AC power supply is grounded, and the other end of the AC power supply is connected to the high-voltage end of the multi-stage coil high-voltage insulator under test; the load is connected to the low-voltage end of the multi-stage coil high-voltage insulator under test and is arranged on the crossarm of the grounded metal bracket; the grounded metal bracket is connected to the low-voltage end of the multi-stage coil high-voltage insulator under test, and the bottom end of the grounded metal bracket is grounded; the AC power supply is used to apply voltage to the multi-stage coil high-voltage insulator under test.

[0009] The data acquisition and processing device is used to connect to the high-voltage end and low-voltage end of the multi-stage coil high-voltage insulator during testing, communicate with the high-current generator, collect and process the data of the multi-stage coil high-voltage insulator, and send the processed data to the high-current generator so that the high-current generator can adjust the magnitude of the high current according to the received data.

[0010] Further optimization involves adjusting the distance between the connection between the output terminal of the high-frequency power conversion device and the high-voltage terminal of the high-voltage insulator of the multi-stage coil under test, and the equalizing ring on the high-voltage side. d 1 is greater than or equal to the insulation distance between the output terminal of the high-frequency power conversion device and the high-voltage terminal of the high-voltage insulator of the multi-stage coil under test:

[0011] d 1≥ U 1 / ( E * K T )* f 1( d 1)).

[0012] f 1( d 1) = 0.9*(1+ d 1 / r 1), r1=min(r a ,r b )

[0013] in, U 1 represents the voltage of the equalizing ring. E For permitted electric fields, K T This is the atmospheric correction factor. f 1( d1) is a function of the first electric field inhomogeneity coefficient, r a Let r be the radius of curvature of the insulating support. b The equivalent radius of curvature of the equalizing ring is given.

[0014] Further optimization involves adjusting the distance between the insulating support and the equalizing ring. d 2≥ U 1 / ( E * K T )* f 2 ( d 2));

[0015] f 2 ( d 2) = 0.9*(1+ d 2 / r 2 ), r=min(r a ,r b );

[0016] in, f 2( d 2) is a function of the second electric field non-uniformity coefficient.

[0017] Further optimization involves adjusting the distance between the grounding metal support and the equipotential ring. d 3≥ U 1 / ( E * K T )* f 3 ( d 3)) ;

[0018] f 3 ( d 3) =0.9*(1+ d 3 / r 3 ), r3=min(r c ,r b )

[0019] in, f 3( d 3) is a function of the third electric field non-uniformity coefficient, r c The radius of curvature of the grounding metal support.

[0020] Further optimization involves the distance between the horizontal section of the lead wire of the high-voltage insulator of the multi-stage coil under test and the top of the equalizing ring.l 1 is:

[0021] l 1≥ U 1 / ( E * K T )* f 4( l 1)).

[0022] f 4( l 1) = 0.9 * (1 + l 1 / r 4), r4=min(r d ,r e );

[0023] in, f 4( l 1) is a function of the fourth electric field inhomogeneity coefficient, r d Let r be the radius of curvature of the conductor. e The radius of curvature is the closest point between the high-voltage insulator of the multi-stage coil being tested and the conductor.

[0024] Further optimization involves the distance between the vertical section of the lead-out wire of the high-voltage insulator of the multi-stage coil under test and the edge of the equalizing ring. l 2 is:

[0025] l 2≥ U 1 / ( E * K T )* f 5 ( l 2 ));

[0026] f 5 ( l 2 )=0.9*(1+ l 2 / r 4);

[0027] f 5 ( l 2 ) is a function of the fifth electric field non-uniformity coefficient.

[0028] Further optimization involves determining the distance between the outlet of the lead wire of the multi-stage coil high-voltage insulator and the high-voltage end of the multi-stage coil high-voltage insulator. D 1 is greater than or equal to its surface flashover distance:

[0029] D 1≥ U 1 / ( E l *K T )

[0030] In the formula, E l The allowable field strength for surface flashover.

[0031] Further optimization involves calculating the relationship between the maximum electric field of the multi-stage coil high-voltage insulator and the radius of curvature of the lead wires on the surface of the multi-stage coil high-voltage insulator based on the Poisson equation, thereby obtaining the minimum allowable radius of curvature of the lead wires of the multi-stage coil high-voltage insulator under test.

[0032] This invention provides a method for synchronously simulating high voltage and high current insulator testing. Based on the aforementioned insulator testing system, a withstand voltage test is performed on a multi-stage coil high voltage insulator. The method includes: connecting the AC power supply to the multi-stage coil high voltage insulator under test; controlling the AC power supply to apply voltage to the multi-stage coil high voltage insulator under test; continuously increasing the voltage on the multi-stage coil high voltage insulator under test; and observing whether the multi-stage coil high voltage insulator under test generates surface discharge or gas breakdown during the voltage increase process.

[0033] If the tested multi-stage coil high-voltage insulator shows no discharge during the pressurization process, then connect the high-current generator, the energy harvesting transformer, the high-frequency power conversion device, and the tested multi-stage coil high-voltage insulator. Control the high-current generator to directly apply the generated high current to the multi-stage coil high-voltage insulator through the output terminal of the energy harvesting transformer and the high-frequency power conversion device, and control the high current loading rate to not exceed [a certain value]. I N / t 0, t 0 represents the adjustable and stable duration of the large current generated by the high-current generator. I N The rated current of the system is used; after the voltage and high current reach the preset stable conditions, various indicators of the high-voltage insulator of the multi-stage coil are measured.

[0034] This invention also provides a method for synchronously simulating high voltage and high current insulator testing. Based on the aforementioned insulator testing system, the method tests the wireless power transmission power of multi-stage coil high voltage insulators. The method includes: connecting the high-frequency power conversion device, the AC power supply, and the multi-stage coil high voltage insulator under test; controlling the high-frequency power conversion device to apply a pulse voltage to the multi-stage coil high voltage insulator under test; and controlling the AC power supply to apply a voltage to the multi-stage coil high voltage insulator under test; and recording the response voltage waveform of the multi-stage coil high voltage insulator in response to the pulse voltage.

[0035] If the high-frequency power conversion device applies a pulse voltage to the multi-stage coil high-voltage insulator under test, and the multi-stage coil high-voltage insulator does not discharge, and the waveform distortion rate of the distorted waveform in the response voltage waveform is within the allowable range, then the insulator test system is considered to be able to withstand the pulse voltage.

[0036] After confirming that the insulator testing system can withstand pulse voltage, disconnect the high-frequency power conversion device from the multi-stage coil high-voltage insulator under test, and connect the high-current generator, the energy harvesting transformer, and the high-frequency power conversion device. Adjust the voltage and current synchronous trigger control logic. When the voltage rise rate is detected to be higher than the set value, immediately connect the high-frequency power conversion device to the multi-stage coil high-voltage insulator to complete the voltage and current pulse synchronous excitation. Record the observed signals of the multi-stage coil high-voltage insulator during the application of voltage and current to obtain the wireless power transmission data of the multi-stage coil high-voltage insulator.

[0037] The present invention has the following advantages:

[0038] This invention can simultaneously simulate the high voltage and high current of transmission lines under laboratory conditions; it can not only realize the withstand voltage test of multi-stage coil high voltage insulators during wireless power transmission, but also realize the withstand voltage test of power equipment such as cables, bushings and ordinary insulators under loaded current conditions.

[0039] Due to laboratory capacity limitations, it is difficult for a single device to simultaneously provide high voltage and high current to the multi-stage coil high-voltage insulator under test (otherwise, the device capacity would be too large). Therefore, the voltage and current generating devices can only generate the required voltage and current for the multi-stage coil high-voltage insulator under test separately, and then apply them simultaneously. A high-current generating device is used to generate a current with a maximum amplitude of 1 kA. The current flows through the energy harvesting transformer, which can then obtain energy. The energy harvesting transformer is fixed with a height-adjustable insulating bracket to meet the energy transmission distance of multi-stage coil high-voltage insulators of different voltage levels. The distance between the energy harvesting transformer and the high-voltage end of the multi-stage coil high-voltage insulator is designed to be adjustable to prevent the energy harvesting transformer, which is close to ground potential, from discharging into the high-voltage equalization ring or affecting the surface insulation of the multi-stage coil high-voltage insulator under test. In addition, the distance between the grounding metal bracket and the equalization ring is also adjustable to prevent the grounding metal bracket from discharging into the high-voltage end of the multi-stage coil high-voltage insulator.

[0040] When testing the insulation performance of multi-stage coil high-voltage insulators during wireless power transfer, the AC power supply and high-current generator can be operated simultaneously. Before testing, the insulating support needs to be adjusted so that the distance between the high-voltage lead of the multi-stage coil high-voltage insulator under test and the equalizing ring at the high-voltage end is the same as the actual distance; the distance between the energy harvesting transformer and the high-voltage end of the multi-stage coil high-voltage insulator must be sufficiently large to avoid affecting the insulation performance of the multi-stage coil high-voltage insulator; and the grounding metal support must be kept sufficiently far from the high-voltage end of the multi-stage coil high-voltage insulator to prevent discharge to ground at the high-voltage end of the multi-stage coil high-voltage insulator. Furthermore, to verify whether the multi-stage coil high-voltage insulator can stably harvest energy under power frequency withstand voltage, the energy harvesting characteristics of the multi-stage coil high-voltage insulator under different withstand voltage times can also be tested. When testing the withstand voltage performance of power equipment such as cables, bushings, and ordinary insulators, the high-current generator and AC power supply can be directly connected to the power equipment, with the AC power supply and high-current generator operating simultaneously to verify the operating status of the power equipment under high-voltage and high-current conditions. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the test system structure of the present invention.

[0042] In the diagram: 1-High current generator, 2-Energy transformer, 3-Insulating support, 4-High frequency power conversion device, 5-AC power supply, 6-Grounding metal support, 7-Load, 8-Data acquisition and processing device, 9-High current generator, 10-Protective resistor, 11-Adjustable resistor, 12-Multi-stage coil high-voltage insulator, 13-Crossarm, 14-Voltage divider capacitor, 15-Equalizing ring. U 0 represents the load voltage. I 0 represents the load current. U in The input voltage at the high-voltage end of the multi-stage coil high-voltage insulator. I in This refers to the input current at the high-voltage end of the multi-stage coil high-voltage insulator; U The voltage applied by the AC power source. Specific implementation methods

[0043] The specific implementation method of the present invention will be further described in detail below with reference to the accompanying drawings.

[0044] like Figure 1 As shown, an insulator testing system for synchronously simulating high voltage and high current includes a high current generating device 1, an energy harvesting transformer 2, an insulating support 3, a high frequency power conversion device 4, an AC power supply 5, a grounding metal support 6, a load 7, and a data acquisition and processing device 8. The high current generating device includes a high current generator 9, a protective resistor 10, and an adjustable resistor 11.

[0045] An insulating bracket 3 supports the energy harvesting transformer 2, ensuring its insulation from ground. The energy harvesting transformer 2 is installed in the series circuit of the high-current generating device 1, and its output terminal is directly connected to the input terminal of the high-frequency power conversion device 4. The high-voltage end of the multi-stage coil high-voltage insulator 12 under test is equipped with an equalizing ring 15. The output terminal of the high-frequency power conversion device 4 is connected to the high-voltage end of the multi-stage coil high-voltage insulator 12 under test. The high-current generating device is used to apply a large current to the multi-stage coil high-voltage insulator under test through the energy harvesting transformer and the high-frequency power conversion device. One end of the AC power supply 5 is grounded, and the other end of the AC power supply 5 is connected to the high-voltage end of the multi-stage coil high-voltage insulator 12 under test. The AC power supply is used to apply voltage to the multi-stage coil high-voltage insulator under test.

[0046] Load 7 is connected to the low-voltage end of the multi-stage coil high-voltage insulator 12 under test, and load 7 is arranged on the crossarm of the grounding metal support 6; the grounding metal support 6 is connected to the low-voltage end of the multi-stage coil high-voltage insulator 12 under test, and the bottom end of the grounding metal support 6 is grounded; the data acquisition and processing device 8 is connected to the voltage dividing capacitor 14 of the AC power supply 5 respectively. When testing the multi-stage coil high-voltage insulator 12, the data acquisition and processing device 8 is also connected to the high-voltage end and the low-voltage end of the multi-stage coil high-voltage insulator 12. The data acquisition and processing device 8 transmits information to the high-current generating device 1 through carrier communication; the data acquisition and processing device 8 is used to acquire and process data during the testing of the multi-stage coil high-voltage insulator 12, and send the processed data to the high-current generating device so that the high-current generating device 1 can adjust the magnitude of the high current according to the received data.

[0047] The high-voltage insulator 12 of the multi-stage coil under test is arranged according to the following method:

[0048] The distance between the connection between the output terminal of the high-frequency power conversion device 4 and the high-voltage terminal of the high-voltage insulator 12 of the multi-stage coil under test, and the high-voltage side equalizing ring. d 1 is greater than or equal to the insulation distance between the two: d 1≥ U 1 / ( E * K T )* f 1( d 1)).

[0049] f 1( d 1) = 0.9*(1+ d 1 / r 1), r1=min(r a ,r b )

[0050] Distance between insulating support 3 and equalizing ring 15 d 2≥U 1 / ( E * K T )* f 2 ( d 2)

[0051] f 2 ( d 2) = 0.9*(1+ d 2 / r 2 ), r=min(r a ,r b ),

[0052] Distance between grounding metal bracket 6 and equalizing ring 15 d 3≥ U 1 / ( E * K T )* f 3 ( d 3) );

[0053] f 3 ( d 3) =0.9*(1+ d 3 / r 3 ), r3=min(r c ,r b ),

[0054] Where, r a Let r be the radius of curvature of the insulating support. b r is the equivalent radius of curvature of the equalizing ring. c The radius of curvature of the grounding metal support; U 1 represents the voltage of the equalizing ring, taken as 35kV. E Permissible electric field ， Take 30 kV / cm as the atmospheric correction factor. K T Take 0.987; f 1( d 1) is a function of the first electric field non-uniformity coefficient. f 2( d 2) is a function of the second electric field non-uniformity coefficient. f 3( d 3) is a function of the third electric field non-uniformity coefficient, which is ultimately determined in this embodiment. d 1 is 3cm.d 2 is 3.1cm. d 3 is 3.2cm.

[0055] The 12 lead wires of the high-voltage insulator of the multi-stage coil under test are arranged according to the following method:

[0056] The distance between the horizontal section of the lead wire of the multi-stage coil high-voltage insulator 12 and the top of the equalizing ring 15 l 1 is:

[0057] l 1≥ U 1 / ( E * K T )* f 4( l 1)).

[0058] f 4( l 1) = 0.9 * (1 + l 1 / r 4), r4=min(r d ,r e );

[0059] in, f 4( l 1) is a function of the fourth electric field inhomogeneity coefficient, r d Let r be the radius of curvature of the conductor. e The radius of curvature is the closest point between the high-voltage insulator of the multi-stage coil under test and the conductor.

[0060] The distance between the vertical section of the lead wire of the high-voltage insulator of the multi-stage coil under test and the edge of the equalizing ring l 2 is:

[0061] l 2≥ U 1 / ( E * K T )* f 5 ( l 2 ));

[0062] f 5 ( l 2 )=0.9*(1+ l 2 / r 4);

[0063] f 5 ( l 2 ) is a function of the fifth electric field non-uniformity coefficient.

[0064] The distance between the outlet of lead 12 of the multi-stage coil high-voltage insulator under test and the high-voltage end of the multi-stage coil high-voltage insulator D 1 is greater than or equal to its surface flashover distance:

[0065] D 1≥ U 1 / ( E l * K T )

[0066] In the formula, E l To determine the allowable field strength for surface flashover, we take 10 kV / cm. This is the final value determined in this embodiment. l 1 is 2.8cm. D 1 is 4.1cm.

[0067] Minimum permissible radius of curvature of lead 12 of the high voltage insulator of the multi-stage coil under test r The minimum permissible radius of curvature of the 12 leads of the multi-stage coil high-voltage insulator was determined by the following method: Based on finite element analysis software, the relationship between the maximum electric field of the multi-stage coil high-voltage insulator and the radius of curvature of the lead wires on the surface of the multi-stage coil high-voltage insulator was calculated according to the Poisson equation. r It is 1 cm.

[0068] After setting up the high-voltage insulator 12 and its leads for the multi-stage coil under test, the experiment can be carried out.

[0069] The withstand voltage test of a multi-stage coil high-voltage insulator is conducted as follows: The connection between the AC power supply and the multi-stage coil high-voltage insulator under test is established. The AC power supply 5 is controlled to apply voltage to the multi-stage coil high-voltage insulator 12 under test, and the voltage is continuously increased. Care is taken to ensure that the voltage increase rate does not exceed 10V / s, so as to observe whether surface discharge or gas breakdown occurs in the multi-stage coil high-voltage insulator 12 during the voltage increase process. If no obvious discharge phenomenon is observed in the multi-stage coil high-voltage insulator 12 when the voltage increases to 1.1 times the system operating voltage (the system operating voltage is equal to the equalizing ring voltage), then the voltage is adjusted to the system operating voltage. If, 10 minutes after the voltage is adjusted to the system operating voltage, the high-voltage insulator 12 of the multi-stage coil under test still shows no discharge, then the current loop between the high-frequency power conversion device 4 and the high-voltage insulator 12 of the multi-stage coil under test is connected (i.e., the connection between the high-current generating device 1, the energy harvesting transformer 2, the high-frequency power conversion device 4, and the high-voltage insulator 12 of the multi-stage coil under test is connected). The high-current generating device 1 is then controlled to apply the generated high current to the high-voltage insulator 12 of the multi-stage coil under test through the energy harvesting transformer 2 and the high-frequency power conversion device 4, while controlling the loading rate of the high current to not exceed [a certain value]. I N / t 0 (unit: A / s)t 0 represents the adjustable and stable duration of the high-current process applied by the high-current generator 1. I N The rated current of the system; after the voltage and high current stabilize and the preset stability conditions are met, various indicators of the multi-stage coil high-voltage insulator 12 can be measured.

[0070] The current can be reduced more quickly while the voltage remains constant (to prevent voltage changes during the voltage reduction process from causing coupling-induced overvoltage in current-carrying devices), until the current drops to the system's rated current. I N When the voltage drops to 5%, disconnect the connection between the high-frequency power conversion device 4 and the multi-stage coil high-voltage insulator 12, and disconnect the connection between the AC power supply 5 and the multi-stage coil high-voltage insulator 12; and turn off the AC power supply 5; wherein the rate of voltage reduction is twice the rate of voltage increase.

[0071] The wireless power transmission power of a multi-stage coil high-voltage insulator was tested. The process involved connecting the high-frequency power conversion device, AC power supply, and the multi-stage coil high-voltage insulator under test. The high-frequency power conversion device was controlled to apply a pulse voltage to the multi-stage coil high-voltage insulator (e.g., controlling the high-frequency power conversion device 4 to generate a pulse voltage exceeding 185kV). The response voltage waveform of the multi-stage coil high-voltage insulator 12 in response to the pulse voltage was recorded. If, during the process of the high-frequency power conversion device applying pulse voltage to the multi-stage coil high-voltage insulator under test, after the high-frequency power conversion device applied 5 pulse voltages to the multi-stage coil high-voltage insulator under test, no discharge phenomenon occurred in the multi-stage coil high-voltage insulator 12, and the distorted waveform in the response voltage waveform... If the distortion rate is within 5%, the insulator testing system is considered to be able to withstand pulse overvoltage. Then, the connection between the high-frequency power conversion device and the multi-stage coil high-voltage insulator under test is disconnected, and the connection between the high current generator 1, the energy harvesting transformer 2 and the high-frequency power conversion device 4 is connected. The voltage and current synchronous triggering control logic is adjusted. According to the rising edge triggering method, when the voltage rise rate is detected to be higher than 1000V / s, the high-frequency power conversion device 4 is immediately connected to the multi-stage coil high-voltage insulator 12 to complete the voltage and current pulse synchronous excitation. The observation signal of the multi-stage coil high-voltage insulator 12 during the application of voltage and current is recorded to obtain the wireless power transmission data of the multi-stage coil high-voltage insulator.

[0072] After completing the test and recording of the wireless power transmission power of the multi-stage coil high-voltage insulator, first disconnect the connection between the high current generator 1, the energy harvesting transformer 2, the high-frequency power conversion device 4 and the multi-stage coil high-voltage insulator, and then disconnect the connection between the AC power supply 5 and the multi-stage coil high-voltage insulator 12.

[0073] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A synchronous simulation system for testing insulators under high voltage and high current, characterized in that, include: High current generating device, energy harvesting transformer, insulating support, high frequency power conversion device, AC power supply, grounding metal support, load, data acquisition and processing device; An insulating bracket supports the energy harvesting transformer, which is installed in the series circuit of the high-current generator. The output terminal of the energy harvesting transformer is directly connected to the input terminal of the high-frequency power conversion device. The high-voltage end of the multi-stage coil high-voltage insulator under test is equipped with an equalizing ring, and the output terminal of the high-frequency power conversion device is connected to the high-voltage end of the multi-stage coil high-voltage insulator under test. The high-current generator is used to apply a large current to the multi-stage coil high-voltage insulator under test through the energy harvesting transformer and the high-frequency power conversion device. One end of the AC power supply is grounded, and the other end of the AC power supply is connected to the high-voltage end of the multi-stage coil high-voltage insulator under test. The load is connected to the low-voltage end of the multi-stage coil high-voltage insulator under test, and the load is arranged on the crossarm of the grounding metal bracket; the grounding metal bracket is connected to the low-voltage end of the multi-stage coil high-voltage insulator under test, and the bottom end of the grounding metal bracket is grounded; the AC power supply is used to apply voltage to the multi-stage coil high-voltage insulator under test. The data acquisition and processing device is connected to the voltage divider capacitor of the AC power supply. The data acquisition and processing device is used to connect to the high voltage end and low voltage end of the multi-stage coil high voltage insulator when testing it. It is also connected to the high current generator for communication. The device collects and processes the data of the multi-stage coil high voltage insulator and sends the processed data to the high current generator so that the high current generator can adjust the magnitude of the high current according to the received data.

2. The insulator testing system for synchronously simulating high voltage and high current as described in claim 1, characterized in that, The distance d1 between the connection between the output terminal of the high-frequency power conversion device and the high-voltage terminal of the multi-stage coil high-voltage insulator under test and the equalizing ring on the high-voltage side is greater than or equal to the insulation distance between the output terminal of the high-frequency power conversion device and the high-voltage terminal of the multi-stage coil high-voltage insulator under test. d1≥U1 / ((E*K T )*f1(d1); f1(d1)= 0.9*(1+ d1 / r1), r1=min(r a ,r b ) Where U1 is the equalizing ring voltage, E is the allowable electric field, and K T Here, f1(d1) is the atmospheric correction coefficient, f1(d1) is a function of the first electric field inhomogeneity coefficient, and r a Let r be the radius of curvature of the insulating support. b The equivalent radius of curvature of the equalizing ring is given.

3. The insulator testing system for synchronously simulating high voltage and high current according to claim 2, characterized in that, The distance d2 between the insulating support and the equalizing ring is greater than or equal to U1 / (E*K). T )*f2(d2) ) f2(d2) = 0.9*(1+d2 / r2), r2=min(r a ,r b ); Where f2(d2) is a function of the second electric field inhomogeneity coefficient.

4. The insulator testing system for synchronously simulating high voltage and high current according to claim 3, characterized in that, The distance d3 between the grounding metal support and the equipotential ring is greater than or equal to U1 / (E*K). T )* f3(d3) ) f3(d3) =0.9*(1+d3 / r3), r3=min(r c ,r b ) Where f3(d3) is a function of the third electric field inhomogeneity coefficient, r c The radius of curvature of the grounding metal support.

5. The insulator testing system for synchronously simulating high voltage and high current according to claim 4, characterized in that, The distance l1 between the horizontal section of the lead wire of the high-voltage insulator of the multi-stage coil under test and the top of the equalizing ring is: l1≥U1 / ((E*K T )*f4(l1)); f4(l1)=0.9*(1+l1 / r4), r4=min(r d ,r e ); Where f4(l1) is a function of the fourth electric field inhomogeneity coefficient, r d Let r be the radius of curvature of the conductor. e The radius of curvature is the closest point between the high-voltage insulator of the multi-stage coil being tested and the conductor.

6. The insulator testing system for synchronously simulating high voltage and high current according to claim 5, characterized in that, The distance l2 between the vertical section of the lead wire of the high-voltage insulator of the multi-stage coil under test and the edge of the equalizing ring is: l2≥U1 / ((E*K T )*f5 (l2)); f5 (l2)=0.9*(1+l2 / r4)； f5 (l2) is a function of the fifth electric field inhomogeneity coefficient.

7. The insulator testing system for synchronously simulating high voltage and high current as described in claim 6, characterized in that, The distance D1 between the outlet of the lead wire of the multi-stage coil high-voltage insulator under test and the high-voltage terminal of the multi-stage coil high-voltage insulator is greater than or equal to its surface flashover distance. D1≥U1 / (E l *K T ); In the formula, E l The allowable field strength for surface flashover.

8. The insulator testing system for synchronously simulating high voltage and high current according to claim 7, characterized in that, The relationship between the maximum electric field of a multi-stage coil high-voltage insulator and the radius of curvature of the lead wires on the surface of the multi-stage coil high-voltage insulator is calculated based on the Poisson equation, and the minimum allowable radius of curvature of the lead wires of the multi-stage coil high-voltage insulator under test is obtained.

9. A method for synchronously simulating high-voltage, high-current insulator testing, based on the insulator testing system described in claim 1, for conducting withstand voltage tests on multi-stage coil high-voltage insulators, characterized in that... include: Connect the AC power supply to the high-voltage insulator of the multi-stage coil under test, control the AC power supply to apply voltage to the high-voltage insulator of the multi-stage coil under test, and continuously increase the voltage to the high-voltage insulator of the multi-stage coil under test. Observe whether the high-voltage insulator of the multi-stage coil under test generates surface discharge or gas breakdown during the voltage increase process. If the tested multi-stage coil high-voltage insulator shows no discharge during the pressurization process, then connect the high-current generator, the energy harvesting transformer, the high-frequency power conversion device, and the tested multi-stage coil high-voltage insulator. Control the high-current generator to directly apply the generated high current to the multi-stage coil high-voltage insulator through the output terminal of the energy harvesting transformer and the high-frequency power conversion device, ensuring the high-current loading rate does not exceed I. N / t0, where t0 is the adjustable stable duration of the large current generated by the large current generator, I N The rated current of the system is used; after the voltage and high current reach the preset stable conditions, various indicators of the high-voltage insulator of the multi-stage coil are measured.

10. A method for synchronously simulating high-voltage, high-current insulator testing, based on the insulator testing system described in claim 1, for testing the wireless power transmission of multi-stage coil high-voltage insulators, characterized in that... include: The connection between the high-frequency power conversion device, the AC power supply and the high-voltage insulator of the multi-stage coil under test is established. The high-frequency power conversion device is controlled to apply a pulse voltage to the high-voltage insulator of the multi-stage coil under test, and the AC power supply is controlled to apply a voltage to the high-voltage insulator of the multi-stage coil under test. The response voltage waveform of the high-voltage insulator of the multi-stage coil in response to the pulse voltage is recorded. If the high-frequency power conversion device applies a pulse voltage to the multi-stage coil high-voltage insulator under test, and the multi-stage coil high-voltage insulator does not discharge, and the waveform distortion rate of the distorted waveform in the response voltage waveform is within the allowable range, then the insulator test system is considered to be able to withstand the pulse voltage. After confirming that the insulator testing system can withstand pulse voltage, disconnect the high-frequency power conversion device from the multi-stage coil high-voltage insulator under test, and connect the high-current generator, the energy harvesting transformer, and the high-frequency power conversion device. Adjust the voltage and current synchronous trigger control logic. When the voltage rise rate is detected to be higher than the set value, immediately connect the high-frequency power conversion device to the multi-stage coil high-voltage insulator to complete the voltage and current pulse synchronous excitation. Record the observed signals of the multi-stage coil high-voltage insulator during the application of voltage and current to obtain the wireless power transmission data of the multi-stage coil high-voltage insulator.

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