Power supply system convenient for processing interphase short circuit

Abstract

The invention discloses a power supply system convenient for processing interphase short circuit, which comprises a power supply and a three-phase line, a plurality of partition switches are arranged on the three-phase line and divide the three-phase line into a plurality of protection areas, and a plurality of section switches are arranged in the protection areas. A lower port of the section switch is connected with the ground or a common wire through a grounding switch, a bus of the three-phase line or a system neutral point is connected with the ground or the common wire through a signal generation switch, and the section switch can detect current signals and can trip according to preset current conditions. The section switch can also detect a voltage signal and can trip according to a preset voltage condition. The system can cut off section switches closest to the two sides of an inter-phase short-circuit fault point so as to cut off the short-circuit fault and enable the system to be self-healed, operation is convenient, hardware used is relatively reduced, and cost is low.

Description

technical field [0001] The invention relates to the field of power system protection, in particular to a power supply system that is convenient for handling interphase short circuits. Background technique [0002] Regarding the treatment of phase-to-phase short-circuit in a three-phase power system, the current common practices are: 1. The method of reclosing: first cut off the first circuit breaker on the line and then close the first circuit breaker, if it is instantaneous phase-to-phase The short circuit is eliminated after closing the first circuit breaker, and the normal power supply is continued. 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. The time difference matching method is adopted: that is, the same circuit breaker can set different overcurrent trip times according to the distance from the power source. The closer the distance to the power source, th...

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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 patent application adopts the method of constructing the detection circuit twice, which requires a lot of hardware, complicated operation, and not convenient to use

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