A Bus Differential Protection Blocking Standby Self-casting Circuit

Abstract

An embodiment of the invention provides a bus differential protection latching spare power automatic switching loop. The loop is characterized in that a bus differential action contact I in a first group and a bus differential action contact II in a second group are parallelly connected and then connected into a latching mother stock spare power automatic switching loop to realize 'OR' logic latching mother stock spare power automatic switching, and another bus differential action contact I in the first group and another bus differential action contact II in the second group are serially connected and then connected into a spare power automatic switching main latching loop to realize 'AND' logic latching spare power automatic switching. Latching mother stock spare power automatic switching is ensured when any bus fails, spare power automatic switching success rate can be increased in a spare power automatic switching mode of a line, power supply reliability is improved, and failure of a device is avoided by latching spare power automatic switching when two buses simultaneously fail (possibly with dead zone failure or mother stock switch failure and the like).

Description

technical field [0001] The invention relates to the technical field of electric power system and automation thereof, in particular to a bus differential protection locking standby self-injection circuit. Background technique [0002] With the development of the national economy, the power grid has higher and higher requirements on the reliability of power supply. Bus differential protection and standby automatic switching are important system equipment to ensure the safe and stable operation of the power grid. In the power system, the 110kV busbars of some 110kV stations adopt single-busbar separate wiring, and are usually equipped with busbar differential protection and standby automatic switching. The main relationship of the circuit connection is ( figure 1 ): Connect two circuit breakers to Line I and Line II respectively. Wherein, the line I is the source power supply, and the line II is the backup power supply; or the line I is the backup power supply, and the line I...

AI Technical Summary

Problems solved by technology

[0009] To sum up, the blocking loop of the prior art can only play a good role in the bus distribution backup self-switching mode to ensure the reliability of power supply; while in the line backup self-switching mode, there is no need to block the backup self-switching mode, and even start To the opposite effect, reducing the reliability of power supply

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