Method for detecting intermittent high-resistance grounding fault through intermittent detection

A high-resistance ground fault and detection method technology, applied in the direction of measuring electricity, measuring devices, measuring electrical variables, etc., to achieve the effects of reliable work, improved sensitivity, and simple trigger conditions

Active Publication Date: 2014-01-22
STATE GRID CORP OF CHINA +1
View PDF3 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the high-resistance ground fault that is difficult to detect by traditional protection methods is a difficult problem in this type of system.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for detecting intermittent high-resistance grounding fault through intermittent detection

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0046] The present invention will be further described below in conjunction with the accompanying drawings.

[0047] Intermittent high-impedance ground fault detection is mainly used to identify the faults that cannot be detected due to the intermittent occurrence of the fault, and because most of the intermittent faults contain a large amount of high frequency, the distributed capacitance will also be on the sound line. If a large disturbance occurs, it is necessary to identify the fault line; the intermittent fault detection focuses on the change of the zero-sequence current amplitude.

[0048] Therefore, in this technical solution, the focus of intermittent high-resistance ground fault detection is to use the zero-sequence current amplitude to identify the fault line.

[0049] figure 1 In , a schematic block diagram of the detection method of the present invention is given.

[0050] In the fault circuit of the neutral point non-resonant grounding system (the neutral point...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a method for detecting an intermittent high-resistance grounding fault through intermittent detection and belongs to the field of emergency protection circuit devices. The method comprises the steps that detected forward fault pulses of intermittent power counted within a preset time window and the result of pulse counting is compared with a preset counting threshold when the timing is ended; if a counted value exceeds the preset counting threshold, a fierce transient state is deemed to occur within short time and a relay protection system gives out an alarm of the detected grounding fault as the intermittent high-resistance fault. The method for detecting the intermittent high-resistance grounding fault through intermittent detection has the advantages that the intermittent high-resistance grounding fault can be detected more sensitively, the faulted line can be removed, the sensitivity of a power supply line protection device is improved, the protection effect of the existing relay protection system/device is fully exerted, the continuous and stable operation of the entire medium-voltage power distribution system is improved and the safety performance of the entire power supply system is guaranteed. The method can be widely used in the field of high-resistance grounding fault detection and the relay protection of the medium-voltage power distribution system with a neutral point which is effectively grounded.

Description

technical field [0001] The invention belongs to the field of emergency protection circuit devices, in particular to a detection / protection method for high-resistance grounding faults in cable or line systems. Background technique [0002] In my country's power system, the AC voltage level with a nominal voltage of 1kV and below is defined as low voltage, the AC voltage level with a nominal voltage of 1kV and below 330kV is defined as high voltage, and the AC voltage level with a nominal voltage of 330kV and above The voltage level is defined as ultra-high voltage, and the AC voltage level with a nominal voltage of 1000kV and above is defined as ultra-high voltage; the standard document of the Institute of Electrical and Electronic Engineers (IEEE) defines the voltage from 2.4kV to 69kV The level is called medium voltage; in the normative documents of my country's State Grid Corporation (State Grid), the voltage level from 1kV to 20kV is called medium voltage. [0003] The gro...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01R31/02
Inventor 顾劲岳王乃盾许刚任丽佳董秋丽
Owner STATE GRID CORP OF CHINA
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products