Method and spare power automatic switching device for detecting faults on basis of GPS (global positioning system) synchronous phase differential method

Abstract

An embodiment of the invention provides a method and a spare power automatic switching device for detecting faults inside and outside a bus area on the basis of a GPS (global positioning system) synchronous phase differential method. The method includes judging that a power system comprising the bus area and a line area fails; acquiring a phase angle beta between a positive-sequence current fault component after the fault and load current before the fault according to the GPS synchronous phase differential method; comparing the phase angle beta with a preset constant value delta which is set according to line parameters and load flow direction; judging that equipment outside the bus area fails if the phase angle beta is larger than the delta; and judging that equipment inside the bus area fails if the phase angle beta is not larger than the delta. The method and the spare power automatic switching device for detecting faults inside and outside the bus areas on the basis of the GPS synchronous phase differential method can judge the types of the faults in a transformer substation without bus protection equipment when the faults occur, and the problem that a faulty area is expanded due to blind spare power automatic switching during faults inside the bus area is avoided.

Description

technical field [0001] The present invention relates to a power system protection device, in particular to a method for detecting internal and external faults in a busbar area based on a Global Positioning System (GPS, Global Positioning System) synchronous phase differential method, and a corresponding method for detecting busbars based on a GPS synchronous phase differential method The device for automatically putting into use the backup power supply for internal and external failures (hereinafter referred to as "preparation and automatic switching device"). Background technique [0002] Identifying bus area faults (bus faults and outgoing side faults) is the main task of bus protection equipment. For substations of 220kV and above, bus protection equipment is installed, and the automatic switching device can use the action blocking signal sent by the bus protection device. To distinguish the fault type when the system fails, whether it is a bus area fault or a line area f...

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Problems solved by technology

[0004] However, in the substations for 110kV and below, most of them do not have busbar protection equipment, so for a long time, when the power system fails and loses voltage, the backup automatic switching device of 110kV and below cannot distinguish the fault area. The bus area or the line area can only be regarded as the line area failure by default, resulting in blind automatic switching of the backup power supply, so that when the bus area fails, the backup automatic switching device controls the backup power supply to be put into operation, causing the fault area to expand

[0005] For the standby automatic switching device of 110kV and below, in order to avoid blind automatic switching in case of a fault in the bus area, resulting in the expansion of the fault area, a new type of standby automatic switching device is needed, which can be used in substations without busbar protection equipment. Distinguish faults in the bus area or line area, so that the power system can accurately and timely automatically turn on the backup power when the line fails, and restore the normal power supply of the load carried by the bus

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