Method for locating fault source of circuit

Abstract

The invention discloses a method for locating a fault source of a circuit. The method comprises: step one, a spare three-phase line is connected in parallel to an original three-phase line; step two,a plurality of nodes are formed at intervals at the three-phase line between three-phase circuit breakers at the head and tail in a breaking manner and three pairs of electric connection terminals areled out at each node, wherein each pair of electric connection terminals is connected with dotted phases of two paths of three-phase lines; step three, whether a single-phase grounding fault occurs at the three-phase line is determined, the three-phase line and a fault phase with the single-phase grounding fault are determined, and the three-phase circuit breakers at the two ends of the three-phase line with the fault are disconnected; step four, current signals between electric connection terminals at the fault phases of all nodes and corresponding phases at another three-phase line are connected continuously and two continuous largest current signals are taken out; step five, a differential voltage signal between the two largest current signals is measured; and step six, based on the differential voltage signal, the specific location of the fault source is determined. Therefore, quick location of a fault source is realized.

Description

technical field [0001] The invention relates to an intelligent detection system, and more specifically, the invention relates to a method for locating a circuit fault source. Background technique [0002] Single-phase grounding is a single-phase grounding of 10kV (35kV) small current grounding system. Single-phase grounding fault is the most common fault in power distribution system, which mostly occurs in humid and rainy weather. It is caused by many factors such as tree barriers, single-phase breakdown of insulators on distribution lines, single-phase disconnection, and small animal hazards. Single-phase grounding not only affects the normal power supply of users, but also may generate overvoltage, burn out equipment, and even cause phase-to-phase short circuit to expand accidents. [0003] In actual operation, the plastic cloth of the brick factory fell onto the wires due to strong winds, causing the voltage transformers of the substation to burn out, causing equipment d...

AI Technical Summary

Problems solved by technology

Single-phase grounding not only affects the normal power supply of users, but also may generate overvoltage, burn out equipment, and even cause phase-to-phase short circuit to expand accidents

[0003] In actual operation, the plastic cloth of the brick factory fell onto the wires due to strong winds, causing the voltage transformers of the substation to burn out, causing equipment damage and large-scale power outages

After a single-phase ground fault occurs, resonant overvoltage may also occur, which may be several times higher than the normal voltage, endangering the insulation of the substation equipment, and in severe cases, the insulation breakdown of the substation equipment may cause a greater accident

[0004] After a single-phase grounding fault occurs, intermittent arcing grounding may occur, resulting in resonant overvoltage and overvoltage several times higher than the normal voltage. The overvoltage will further cause insulation breakdown of the insulator on the line, resulting in a serious short circuit accident. Burn down part of the distribution transformer, cause the lightning arrester and fuse insulation on the line to break down and burn out, and electrical fires may also occur

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