Unlock instant, AI-driven research and patent intelligence for your innovation.

Traveling wave ranging method and system in parallel connection of arc suppressing coil with small resistance to ground

A low-resistance grounding and arc-suppressing coil technology, applied in the field of power systems, can solve problems such as weak traveling wave signals, large ranging errors, and lack of fault location methods.

Active Publication Date: 2020-07-24
NORTH CHINA ELECTRIC POWER UNIV (BAODING)
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

A common problem with the fault signal ranging method is that if a fault occurs when the voltage is close to the zero-crossing point, the traveling wave signal generated by the fault will be weak, which will easily cause a large ranging error
[0004] In summary, there is a lack of methods in the prior art that can effectively locate faults

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
  • Traveling wave ranging method and system in parallel connection of arc suppressing coil with small resistance to ground
  • Traveling wave ranging method and system in parallel connection of arc suppressing coil with small resistance to ground
  • Traveling wave ranging method and system in parallel connection of arc suppressing coil with small resistance to ground

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0067] refer to figure 1 , the traveling wave ranging method under the parallel connection of arc suppression coil with small resistance to grounding method, including:

[0068] Step S101, acquiring fault information, and judging the fault type according to the fault information;

[0069] Step S102, when the fault type is a single-phase ground fault, a small resistor connected in parallel with the arc suppressing coil is put into operation;

[0070] Step S103, calculate the difference between the arrival times of the zero-mode component of the current traveling wave and the wave head of the line-mode component according to the current waveform before and after the input of the small resistor, and judge the fault area where the fault point is located according to the difference between the arrival times;

[0071] Step S104, in combination with the fault area where the fault point is located, determine the fault segment according to the fault segment location method;

[0072] ...

Embodiment 2

[0120] The traveling wave distance measuring system under the grounding method of the arc suppressing coil connected in parallel with small resistance includes:

[0121] a fault information judging unit, configured to acquire fault information, and judge a fault type according to the fault information;

[0122] A small resistance input unit is used to input a small resistance connected in parallel with the arc suppression coil when the fault type is a single-phase ground fault;

[0123] The waveform recording unit is used to calculate the difference between the arrival time of the zero-mode component of the current traveling wave and the wave head of the line-mode component according to the current waveform before and after the input of the small resistor, and judge the location of the fault point according to the difference between the arrival times failure area;

[0124] a fault section determining unit, configured to determine the fault section according to the fault secti...

Embodiment 3

[0128] EMTP software pair figure 2 The network shown is simulated and analyzed. Assume figure 2 Between FTU4 and FTU5 is the cable line, and other areas are overhead lines. During the simulation process on ATP / EMTP, the fault phases are all phase A, and the fault occurrence time is set to 0.1s, the neutral point small resistor input time is 0.188s, which is the peak time of the voltage, and the sampling frequency is 2MHz. The line-mode and zero-mode wave velocities of overhead lines and cables are shown in Table B1 of Appendix B.

[0129] (1) Analysis of metallic single-phase ground fault

[0130] Assume that the fault occurs at point K of section S, and the fault point is 10,000m away from point P and 30,000m away from the bus. Figure 4 are the line-mode and zero-mode components detected by FTU9, respectively. pass Figure 5 and Figure 6 It can be seen that FTU9 first detects the zero-mode component, and then detects the line-mode component, indicating that after t...

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 provides a traveling wave distance measuring method and system based on a grounding mode of an arc suppression coil and a small resistor connected in parallel. The method comprises the steps of acquiring fault information, and judging a fault type; in the case of a single-phase grounding fault, adding the small resistor which is connected with the arc suppression coil in parallel; according to current waveforms before and after the small resistor is added, calculating a difference between arrival time of wave heads of an earth mode component and an aerial mode component of a current traveling wave, and judging a fault area where a fault point is located according to the difference between the arrival time; in combination with the fault area where the fault point is located, determining a fault section according to a fault section positioning method; calculating an initial calculated fault distance from a transformer substation detection device to the fault point; and correcting the initial calculated fault distance to obtain a final calculated fault distance. A mode of injecting a signal during electrified operation is adopted; primary equipment investment does not need to be added; distance measurement can be completed by utilizing the existing parallel small resistor; relatively few devices are needed; synchronous sampling is not needed; the overall cost is reduced; and the distance measuring accuracy is remarkably improved.

Description

technical field [0001] The invention relates to the technical field of electric power systems, in particular to a traveling wave ranging method and system in a parallel connection of arc suppressing coils with small resistance to grounding. Background technique [0002] my country's 10-35kV medium-voltage distribution network generally adopts the neutral point grounding method through the arc suppression coil, and the problem of fault location after a single-phase ground fault has plagued the power supply operation department for a long time. Distribution network single-phase ground fault location technology can be divided into two types: section location and fault distance measurement. Section location technology is used to determine the section where the fault is located, usually between two FTUs, DTUs or fault indicators. Fault location technology is to calculate the exact distance from the fault point to the bus or detection device. Section positioning technology has be...

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 Patents(China)
IPC IPC(8): G01R31/08G01R31/52
CPCG01R31/086G01R31/50
Inventor 齐郑杭天琦
Owner NORTH CHINA ELECTRIC POWER UNIV (BAODING)