Method for processing interphase short circuit of three-phase power system

Abstract

The invention discloses a three-phase power system interphase short circuit processing method. A plurality of partition switches are arranged on a line, the plurality of partition switches divide the line into a plurality of protection areas, and a plurality of section switches are arranged in the protection areas; when an inter-phase short-circuit fault occurs in a line, the electric energy inlet partition switch cuts off fault current, then a detection loop comprising an inter-phase short-circuit fault point and a fault phase is constructed, controllable current is injected, and the section switch detects the controllable current and trips according to a preset condition so as to cut off the inter-phase short-circuit fault. According to the method, the interphase short circuit fault can be effectively removed, the power failure area can be reduced, and meanwhile, the use of a large-current cut-off switch can be reduced, so that the switch cost is effectively reduced.

Description

technical field [0001] The invention relates to the field of power system protection, in particular to a method for processing short circuits between phases in a three-phase power system. Background technique [0002] At present, when a phase-to-phase short circuit occurs in a certain line of a three-phase power system, the following processing methods are usually adopted: 1. The method of reclosing is adopted: first cut off the first circuit breaker on the line and then close the first circuit breaker, If it is an instantaneous phase-to-phase short circuit and it is eliminated after closing the first circuit breaker, the normal power supply will continue. If the phase-to-phase short-circuit fault still exists after closing the first circuit breaker, cut off the first circuit breaker and wait for maintenance. 2. Adopt the time-level difference coordination method: that is, the same line circuit breaker sets different over-current tripping times according to the distance fro...

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Problems solved by technology

2. Adopt the time-level difference coordination method: that is, the same line circuit breaker sets different over-current tripping times according to the distance from the power supply. The closer the distance to the power supply, the longer the tripping time. Generally, the setting level difference is 100ms. This time is determined by the mechanical switch. The action duration is determined by the time spent on the algorithm. This method can isolate the fault area. However, for faults where the fault point is close to the power supply, the power supply system can withstand short-circuit current for a long time and have a large impact on the power grid.

This method does not carry out partition protection. First, the first circuit breaker must be tripped, so that users on the entire line will be affected, and the blackout area will be large. Reduce switching costs

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