Analysis on improvement scheme of configuration of current transformer and protection for smallcapacity transformer in 220kV system

Abstract

Abstract: The current transformer for the smallcapacity transformer in a 220kV system was configured improperly. When the fault occurred, the current transformer saturated seriously, which led the protection refused to trip or tripped incorrectly and caused the fault enlargement. In order to ensure the reliability of the protection, the current transformer and the protection configuration must be improved. Aiming at the difficulties in the improvement, the improvement scheme of the current transformer and the improvement scheme of the protection configuration were proposed. The implementation of the improvement schemes can increase the reliability of the protection greatly.
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Key words: current transformer, protection configuration, saturation, refuse to trip, transformation ratio, accuracy class, improvement scheme

WU Zhenghua;WANG Dongjue. Analysis on improvement scheme of configuration of current transformer and protection for smallcapacity transformer in 220kV system[J]. Huadian Technology, 2012, 34(S1): 50-51.

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Analysis on improvement scheme of configuration of current transformer and protection for smallcapacity transformer in 220kV system

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