CN-115856554-B - Insulator test system and method for synchronously simulating high voltage and high current

CN115856554BCN 115856554 BCN115856554 BCN 115856554BCN-115856554-B

Abstract

The invention discloses an insulator test system and method for synchronously simulating high-voltage heavy current, wherein the insulator test system comprises a heavy current generating device, an energy taking transformer, an insulating bracket, a high-frequency electric energy conversion device, an alternating current power supply, a grounding metal bracket, a load and a data acquisition and processing device, and can simultaneously provide high voltage required by a withstand voltage test and heavy current required by wireless energy transmission; and controlling the trigger sequence of the high voltage and the high current to realize synchronous control of the generation of the high current and the efficiency test. According to the invention, the voltage withstand test of the multi-stage coil high-voltage insulator can be realized by supplying high voltage through the alternating current power supply, and the transmission efficiency of the multi-stage coil high-voltage insulator can be tested in a period of short time of high current by controlling the triggering sequence of the high voltage and the high current.

Inventors

XIONG JUNJIE
LI CHUNLONG
HUANG HUI
ZHAO HAISEN
XIONG JIANHAO
WU KANG

Assignees

国网江西省电力有限公司电力科学研究院
国家电网有限公司
国网智能电网研究院有限公司
华北电力大学

Dates

Publication Date: 20260505
Application Date: 20230118

Claims (10)

1. The insulator test system for synchronously simulating high-voltage and high-current is characterized by comprising a high-current generating device, an energy taking transformer, an insulating bracket, a high-frequency electric energy conversion device, an alternating current power supply, a grounding metal bracket, a load and a data acquisition and processing device; The high-voltage end of the high-voltage insulator of the multi-stage coil to be tested is provided with a grading ring, and the output end of the high-voltage electric energy conversion device is connected with the high-voltage end of the high-voltage insulator of the multi-stage coil to be tested; One end of the alternating current power supply is grounded, and the other end of the alternating current power supply is connected with the high-voltage end of the measured multi-stage coil high-voltage insulator; the load is connected with the low-voltage end of the high-voltage insulator of the multi-stage coil to be tested, and the load is arranged on the cross arm of the grounding metal bracket; the data acquisition and processing device is connected with a voltage dividing capacitor of the alternating current power supply, and is used for being respectively connected with a high-voltage end and a low-voltage end of the multi-stage coil high-voltage insulator when the multi-stage coil high-voltage insulator is tested, and is in communication connection with the large current generating device, the data of the multi-stage coil high-voltage insulator are acquired and processed, the processed data are sent to the large current generating device, and therefore the large current generating device can adjust the large current according to the received data.
2. The synchronous simulation high-voltage high-current insulator test system according to claim 1, wherein a distance d 1 between a wire between an output end of the high-frequency power conversion device and a high-voltage end of the high-voltage side of the measured multi-stage coil high-voltage insulator and a grading ring on the high-voltage side is equal to or greater than an insulation distance between the output end of the high-frequency power conversion device and the high-voltage end of the measured multi-stage coil high-voltage insulator: d 1 ≥U 1 /（（E*K T ）*f 1 (d 1 )); f 1 (d 1 )= 0.9*(1+ d 1 /r 1 ), r 1 =min(r a ,r b ) Wherein U 1 is the equalizing ring voltage, E is the allowable electric field, K T is the atmospheric correction coefficient, f 1 (d 1 ) is a function of the first electric field non-uniformity coefficient, r a is the insulating support radius of curvature, and r b is the equalizing ring equivalent radius of curvature.
3. The synchronous high-voltage high-current simulating insulator test system according to claim 2, wherein a distance d 2 ≥U 1 /（（E*K T ）*f 2 (d 2 between the insulating holder and the grading ring); f 2 (d 2 ) =0.9*(1+d 2 /r 2 ), r 2 =min(r a ,r b ); wherein f 2 (d 2 ) is a function of the second electric field non-uniformity coefficient.
4. The synchronous high-voltage high-current simulating insulator test system according to claim 3, wherein a distance d 3 ≥U 1 /（（E*K T ）* f 3 (d 3 between the grounded metal bracket and the grading ring); f 3 (d 3 ) =0.9*(1+d 3 /r 3 ), r 3 =min(r c ,r b ) wherein f 3 (d 3 ) is a function of the third electric field non-uniformity coefficient, and r c is the radius of curvature of the grounded metal stent.
5. The synchronous high-voltage high-current simulating insulator test system according to claim 4, wherein a distance l 1 between a horizontal section of the high-voltage insulator outgoing line of the multistage coil to be tested and the top of the equalizing ring is: l 1 ≥U 1 /(（E*K T ）*f 4 (l 1 )); f 4 (l 1 )=0.9*(1+l 1 /r 4 ), r 4 =min(r d ,r e ); wherein f 4 (l 1 ) is a function of the fourth electric field non-uniformity coefficient, r d is the radius of curvature of the wire, and r e is the radius of curvature of the nearest end of the tested multi-stage coil high-voltage insulator and the wire.
6. The synchronous high-voltage high-current simulating insulator test system according to claim 5, wherein the distance l 2 between the vertical section of the high-voltage insulator outgoing line of the multistage coil to be tested and the edge of the equalizing ring is: l 2 ≥U 1 /（（E*K T ）*f 5 (l 2 )); f 5 (l 2 )=0.9*(1+l 2 /r 4 ); f 5 (l 2 ) as a function of the fifth electric field non-uniformity coefficient.
7. The synchronous simulation high-voltage high-current insulator test system according to claim 6, wherein a distance D 1 between an outlet of a high-voltage insulator outgoing line of the multi-stage coil to be tested and a high-voltage end of the multi-stage coil high-voltage insulator is larger than or equal to a surface flashover distance: D 1 ≥U 1 /（E l *K T ); Where E l is strong in the following flashover Xu Yongchang.
8. The synchronous simulation high-voltage high-current insulator test system according to claim 7, wherein the function relation between the maximum electric field of the multi-stage coil high-voltage insulator and the curvature radius of the outgoing line of the multi-stage coil high-voltage insulator is calculated according to a poisson equation, and the minimum allowable curvature radius of the outgoing line of the multi-stage coil high-voltage insulator to be tested is obtained.
9. The method for synchronously simulating high-voltage and high-current insulator test, which is based on the insulator test system of claim 1, is characterized by comprising the following steps: Switching on the connection between the alternating current power supply and the measured multi-stage coil high-voltage insulator, controlling the alternating current power supply to apply voltage to the measured multi-stage coil high-voltage insulator, continuously increasing the voltage to the measured multi-stage coil high-voltage insulator, and observing whether the measured multi-stage coil high-voltage insulator generates creeping discharge or gas breakdown in the voltage increasing process; If the tested multi-stage coil high-voltage insulator has no discharge phenomenon in the pressurizing process, the connection among the large current generating device, the energy-taking transformer, the high-frequency electric energy conversion device and the tested multi-stage coil high-voltage insulator is connected, the large current generating device is controlled to directly load the large current generated by the loading of the multi-stage coil high-voltage insulator through the output end of the energy-taking transformer and the high-frequency electric energy conversion device, the loading rate of the large current is controlled to be not more than I N /t 0 ,t 0 , the adjustable stable duration of the large current generated by the loading of the large current generating device is controlled, I N is the rated current of the system, and various indexes of the multi-stage coil high-voltage insulator are measured after the voltage and the large current reach preset stable conditions.
10. An insulator testing method for synchronously simulating high voltage and large current, which is used for testing wireless energy transmission power of a multistage coil high-voltage insulator based on the insulator testing system as claimed in claim 1, and is characterized by comprising the following steps: Switching on the connection between the high-frequency electric energy conversion device, the alternating current power supply and the tested multi-stage coil high-voltage insulator, controlling the high-frequency electric energy conversion device to apply pulse voltage to the tested multi-stage coil high-voltage insulator, applying voltage to the tested multi-stage coil high-voltage insulator by the alternating current power supply, and recording response voltage waveforms of the multi-stage coil high-voltage insulator in response to the pulse voltage; If the high-frequency electric energy conversion device does not generate discharge phenomenon in the process of applying pulse voltage to the tested multi-stage coil high-voltage insulator and the waveform distortion rate of the distorted waveform in the response voltage waveform is within the allowable range, the insulator test system is considered to be capable of tolerating the pulse voltage; After the insulator test system is confirmed to be capable of tolerating pulse voltage, the connection between the high-frequency electric energy conversion device and the tested multi-stage coil high-voltage insulator is disconnected, the connection among the large-current generation device, the energy-taking transformer and the high-frequency electric energy conversion device is connected, voltage and current synchronous triggering control logic is regulated, when the fact that the voltage rising rate is higher than a set value is detected, the connection between the high-frequency electric energy conversion device and the multi-stage coil high-voltage insulator is immediately conducted, voltage and current pulse synchronous excitation is completed, observation signals of the multi-stage coil high-voltage insulator in the process of being applied with voltage and current are recorded, and data of wireless energy transmission power of the multi-stage coil high-voltage insulator are obtained.

Description

Insulator test system and method for synchronously simulating high voltage and high current Technical Field The invention relates to the technical field of electric power high voltage, in particular to an insulator testing system and method for synchronously simulating high voltage and high current. Background The on-line monitoring device is an effective measure for guaranteeing safe and reliable operation of the power transmission line, however, the power transmission line is wide in distribution and long in distance, and the power supply problem of the on-line monitoring device is difficult to effectively solve. Photovoltaic power supply is the mainstream in the power supply mode of the existing power transmission line on-line monitoring equipment, but the effect of photovoltaic power supply is severely limited by local climate conditions, and the problems of large device size, frequent battery replacement, high maintenance cost, easy damage under severe weather conditions and the like exist. Data in practical engineering applications show that a large number of photovoltaic powered devices are damaged annually by bad weather. Aiming at the problems, scholars at home and abroad propose a plurality of novel power supply modes, wherein magnetic resonance coupling wireless energy transmission is the most mature and practical power supply mode at present. Especially under the condition that the multi-coil wireless power transmission has a certain research basis, the wireless power transmission and supply mode based on the multi-coil high-voltage insulator has more obvious advantages. The electric energy supplied to the electric equipment in the mode is directly sourced from the electric transmission line, and meanwhile, the problem of insulation between the high-voltage electric transmission line and the low-voltage electric equipment is avoided due to the adoption of a wireless mode of multistage magnetic resonance coupling for supplying power. For the application of the multi-stage coil high-voltage insulator, firstly, the transmission power, the efficiency and the voltage resistance of the multi-stage coil high-voltage insulator are tested, if the insulator is tested in a practical application scene, huge cost is generated, the influence on a power transmission line is generated, and most importantly, the safety and the stability of the experiment cannot be ensured. Because the multistage coil high-voltage insulator takes energy in the power transmission line under the actual working condition, the laboratory condition generally cannot meet the test conditions of high current and high voltage at the same time. Therefore, how to simultaneously meet the testing conditions of the multi-stage coil high-voltage insulator with high current and high voltage under the experimental conditions becomes a technical problem to be solved. Disclosure of Invention The invention aims to provide a system and a method for synchronously simulating high-voltage and high-current insulator test, which can realize the voltage-withstanding characteristic and wireless energy-transfer test of a multi-stage coil high-voltage insulator in a laboratory. In view of the above, the invention provides an insulator test system for synchronously simulating high-voltage heavy current, which comprises a heavy current generating device, an energy taking transformer, an insulating bracket, a high-frequency electric energy conversion device, an alternating current power supply, a grounding metal bracket, a load and a data acquisition and processing device; The high-voltage end of the high-voltage insulator of the multi-stage coil to be tested is provided with a grading ring, and the output end of the high-voltage electric energy conversion device is connected with the high-voltage end of the high-voltage insulator of the multi-stage coil to be tested; One end of the alternating current power supply is grounded, and the other end of the alternating current power supply is connected with the high-voltage end of the measured multi-stage coil high-voltage insulator; the load is connected with the low-voltage end of the high-voltage insulator of the multi-stage coil to be tested and is arranged on the cross arm of the grounding metal bracket; The data acquisition and processing device is used for being respectively connected with the high-voltage end and the low-voltage end of the multi-stage coil high-voltage insulator when the multi-stage coil high-voltage insulator is tested, is in communication connection with the high-current generating device, acquires and processes data of the multi-stage coil high-voltage insulator, and sends the processed data to the high-current generating device so that the high-current generating device can adjust the magnitude of high current according to the received data. Further preferably, a distance d 1 between a line between the output end of the high-frequency power conversion device and the high-voltage end of th