CN-115718239-B - GIS field electric pulse partial discharge live detection device and detection method

Abstract

The invention discloses a GIS field electric pulse partial discharge live detection device and a detection method, which relate to the field of live detection of electric equipment, wherein equivalent capacitances between a primary winding and a secondary winding of a current transformer coil are used as electric pulse signal coupling channels, two groups of pulse current signals in a GIS high-voltage conductor are obtained through the two electric pulse signal coupling channels, partial discharge voltage signals with specified frequencies are respectively extracted through an electric pulse partial discharge detection loop, the extracted two groups of electric pulse signals are output to a signal differential mode comparison acquisition module, and electric pulse signals input by the two input channels are compared through the signal differential mode comparison acquisition module, so that interference signals are effectively eliminated; the invention solves the two problems of electric pulse coupling and high-voltage side partial discharge interference of the electrified operation faced by GIS electrified partial discharge pulse detection at the same time, realizes accurate detection of partial discharge during GIS operation, and ensures safe and stable operation of GIS electrical equipment.

Inventors

• LONG YINGKAI
• TAN HUAYONG
• DENG BANGFEI
• LI MINGXING
• YE YINAN
• XIAO LEI
• ZHANG SHIHAI
• WANG QIAN
• LI SIQUAN
• DU MINGMING
• JIANG XIPING
• LUO XIAOXIAO
• She Qianhao
• QIN WEI
• An changping

Assignees

• 国网重庆市电力公司电力科学研究院
• 国家电网有限公司

Dates

Publication Date

20260505

Application Date

20221122

Claims (10)

1. 1. GIS field electric pulse partial discharge live detection device, characterized by comprising: the current transformer is used for acquiring pulse current signals in the GIS high-voltage conductor; The input end of the electric pulse partial discharge detection loop is connected with the grounding end of the current measurement module in the current transformer, and the output end of the electric pulse partial discharge detection loop is connected with the signal acquisition module; The pulse current signal enters an electric pulse partial discharge detection loop through a grounding end of the current measurement module, and the electric pulse partial discharge detection loop extracts partial discharge voltage signals with specified frequency and outputs the extracted electric pulse signals to the signal acquisition module for acquisition and detection; Equivalent capacitances between a primary winding and a secondary winding of the current transformer coil are used as electric pulse signal coupling channels, and two groups of pulse current signals in the GIS high-voltage conductor are obtained through the two electric pulse signal coupling channels; The signal acquisition module is a signal differential mode comparison acquisition module, and the signal differential mode comparison acquisition module compares the electric pulse signals input by the two input channels and effectively eliminates interference signals.
2. 2. The GIS on-site electric pulse partial discharge live detection device according to claim 1, wherein an equivalent capacitance between windings of the current transformer coil is used as an electric pulse signal coupling channel, and pulse current signals in the GIS high-voltage conductor are obtained through the electric pulse signal coupling channel.
3. 3. The GIS field electric pulse partial discharge live detection device according to claim 2, wherein the input ends of the two groups of electric pulse partial discharge detection loops are respectively connected with the grounding end of the current measurement module corresponding to the primary winding and the secondary winding, and the output ends of the two groups of electric pulse partial discharge detection loops are respectively connected with the two input channels of the signal differential mode comparison acquisition module.
4. 4. The GIS field electric pulse partial discharge live detection device according to claim 3, wherein the signal differential mode comparison acquisition module does not record electric pulse signals with the voltage difference of less than 10% of two input channels, and records electric pulse signals with the voltage difference of more than 10% of two input channels.
5. 5. The GIS field electric pulse partial discharge live detection apparatus according to claim 1, wherein the electric pulse partial discharge detection circuit comprises: And the frequency-selecting circuit extracts the electric pulse 200 k-1M Hz frequency partial discharge voltage signal.
6. 6. The GIS field electric pulse partial discharge live detection apparatus of claim 5, wherein the electric pulse partial discharge detection circuit further comprises: the signal amplification circuit adopts an adjustable amplification factor which is 20-500 times, amplifies the extracted electric pulse signal, and outputs the amplified electric pulse signal to the signal acquisition module for acquisition and detection.
7. 7. The GIS field electric pulse partial discharge live detection apparatus of claim 5, wherein the electric pulse partial discharge detection circuit further comprises: and the clamping circuit controls the voltage at two ends of the frequency selection circuit to be more than 1V, ensures the grounding of the current measurement module to be reliable, and simultaneously enables pulse current signals to enter the frequency selection circuit.
8. 8. The GIS field electric pulse partial discharge live detection apparatus of claim 5, wherein the electric pulse partial discharge detection circuit further comprises: And the voltage of the protection ball gap is set at 100V, so as to prevent the fault of the electric pulse partial discharge detection loop.
9. 9. A GIS field electric pulse partial discharge live detection method, characterized in that a GIS field electric pulse partial discharge live detection device based on any one of claims 1-8 comprises: step S1, acquiring a pulse current signal in a GIS high-voltage conductor through a current transformer; step S2, pulse current signals enter an electric pulse partial discharge detection loop through a grounding end of a current measurement module; And step S3, extracting partial discharge voltage signals with specified frequency through an electric pulse partial discharge detection loop, and outputting the extracted electric pulse signals to a signal acquisition module for acquisition and detection.
10. 10. The method for detecting the local discharge of the electric pulse in the GIS according to claim 9, wherein the step S1 includes: The equivalent capacitance between the primary winding and the secondary winding of the current transformer coil is used as an electric pulse signal coupling channel, and two groups of pulse current signals in the GIS high-voltage conductor are obtained through the two electric pulse signal coupling channels; the step S2 includes: Two groups of pulse current signals respectively enter a group of electric pulse partial discharge detection loops through the grounding end of the current measurement module; the step S3 includes: based on two groups of pulse current signals, partial discharge voltage signals with the frequency of 200 k-1M Hz of electric pulses are respectively extracted through corresponding electric pulse partial discharge detection loops, and the extracted two groups of electric pulse signals are output to two input channels of a signal differential mode comparison acquisition module; The signal differential mode comparison acquisition module does not record the electric pulse signals with the voltage difference of less than 10% of the two input channels, and records the electric pulse signals with the voltage difference of more than 10% of the two input channels.

Description

GIS field electric pulse partial discharge live detection device and detection method Technical Field The invention relates to the technical field of application of electric power equipment live detection, in particular to a GIS on-site electric pulse partial discharge live detection device and a detection method. Background The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. The GIS gas-insulated metal-enclosed switchgear (GIS) is necessary equipment in a power grid, reliability of the GIS gas-insulated metal-enclosed switchgear relates to whether the power grid can safely and stably operate, faults of GIS internal insulation can have great influence on stable operation of the GIS, defects inevitably exist in the GIS internal insulation, partial discharge (PARTIAL DISCHARGE, PD) phenomenon can occur under the action of an electric field when the GIS is put into the power grid for use, partial discharge can accelerate GIS internal insulation degradation, GIS insulation breakdown can even occur when the GIS internal insulation is serious, and the reasons of the partial discharge phenomenon of the GIS internal insulation mainly include defects that bubbles, cracks, burrs, impurities and the like inevitably occur in GIS insulation in the processes of GIS manufacturing, transporting and installing, and the like under the effect of overvoltage of a power system, the insulation defects of the GIS in operation can occur partial discharge phenomenon, insulation aging is accelerated, and finally GIS insulation breakdown can not normally operate and even break down, so that huge losses are caused. Therefore, the partial discharge is not only the phenomenon and characterization of the defects and degradation of the insulation, but also the important factors for promoting the insulation aging, so that the partial discharge detection is necessary to be carried out in the GIS operation period, and at present, the partial discharge detection is carried out in real time by utilizing an ultrahigh frequency, ultrasonic and ground electric wave method device in the GIS operation period, the long-term working stability of an online monitoring device is poor, the quantitative judgment of the partial discharge quantity can not be carried out, and the insulation performance can not be accurately estimated. Disclosure of Invention Aiming at the problem that no effective means exists in defect development detection before GIS insulation fault operation at present, the invention provides a GIS field electric pulse partial discharge live detection device and a detection method, which solve the problems of GIS operation power supply side and environment interference, solve the problem of GIS live partial discharge quantitative detection, realize accurate detection of partial discharge during GIS operation, discover insulation internal defects in time and hidden danger caused by the long-term occurrence of partial discharge phenomenon, and ensure safe and stable operation of GIS electrical equipment. The technical scheme of the invention is as follows: a GIS field electric pulse partial discharge live detection device, comprising: the current transformer is used for acquiring pulse current signals in the GIS high-voltage conductor; The input end of the electric pulse partial discharge detection loop is connected with the grounding end of the current measurement module in the current transformer, and the output end of the electric pulse partial discharge detection loop is connected with the signal acquisition module; The pulse current signal enters an electric pulse partial discharge detection loop through the grounding end of the current measurement module, the electric pulse partial discharge detection loop extracts partial discharge voltage signals with specified frequency, and the extracted electric pulse signals are output to the signal acquisition module for acquisition and detection. Further, an equivalent capacitor between windings of the current transformer coil is used as an electric pulse signal coupling channel, and a pulse current signal in the GIS high-voltage conductor is obtained through the electric pulse signal coupling channel. Further, the equivalent capacitance between the primary winding and the secondary winding of the current transformer coil is used as an electric pulse signal coupling channel, and two groups of pulse current signals in the GIS high-voltage conductor are obtained through the two electric pulse signal coupling channels; The electric pulse partial discharge detection circuits are divided into two groups, and the signal acquisition module is a signal differential mode comparison acquisition module; the signal differential mode comparison acquisition module compares the electric pulse signals input by the two input channels and effectively eliminates interference signals; The input ends of the two groups of electric