Bus protection algorithm for realizing GIS accurate fault removing and automatic power supply recovery

Abstract

The invention discloses a bus protection algorithm for realizing GIS accurate fault removing and automatic power supply recovery. The bus protection algorithm comprises the steps that bus wide-range differential current, bus small-range differential current and interval differential current are calculated respectively; faults outside a bus area and faults inside the bus area are distinguished according to actuation of a high-difference-ratio element; when the high-difference-ratio element actuates, the segment of bus on which the faults occur is determined by actuation of a low-difference-ratio element; a fault interval is determined by actuation of an interval ratio differential element; and the type of the faults is judged and the faults are responded according to the actuation situation of the high-difference-ratio element, the low-difference-ratio element and the interval ratio differential element. The beneficial effects of the bus protection algorithm are that the fault position can be accurately judged and the faults can be rapidly removed and isolated so that a situation that all connecting elements are tripped by bus protection when single interval internal faults occur can be prevented, selectivity of bus protection actuation can be guaranteed, accident scope can be reduced and system operation stability can be enhanced.

Description

technical field [0001] The invention relates to the technical field of electric power system relay protection, in particular to a busbar protection algorithm that realizes precise removal of GIS faults and automatic restoration of power supply. Background technique [0002] When a fault occurs in the power system, the selectivity of relay protection requires that the control operation of the circuit breaker be realized within the smallest range and in the place where the impact on the system may be the least, and the fault is disconnected from the system to terminate the fault or system accident. development, to ensure that the non-faulty parts of the system can still continue to operate safely. The busbar protection action will cut off all the components connected to the faulty busbar. Once the busbar protection has a misjudgment or wrong action, the load will be lost and the safety of the equipment will be affected. In severe cases, it will cause a large-scale power outage...

AI Technical Summary

Problems solved by technology

Although this configuration ensures reliability, it cannot meet the selectivity requirements

If a fault occurs between the current transformers on the line side and the busbar side, it is still a single-bay internal fault, not a real busbar fault. The fault between the line-side current transformer and the circuit breaker can be isolated by simply opening the single-bay circuit breaker. The fault between the circuit breaker and the current transformer on the bus side can be isolated only by opening the single-interval knife switch. Now the bus protection action will trip all the components connected to the bus, which actually causes the fault range to expand and lose selectivity

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