220 kV系统小容量变压器电流互感器和保护配置改进方案分析

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

220 kV系统小容量变压器的电流互感器由于配置不当,在故障时造成严重饱和,导致保护拒动或误动,使故障扩大化。为保证保护的可靠性,应对电流互感器和保护配置进行改进。针对改进中的难点,提出了电流互感器改进方案和保护配置改进方案。改进后,保护的可靠性大大提高。

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.