CT断线判据在母线保护中的应用分析

Application Analysis of CT Disconnection Criterion inthe Bus Protection

变电站正常运行过程中存在母线保护间隔电流互感器二次回路断线的概率,而电流互感器二次回路断线会引起母线差动保护误动。为了提高母线保护的整体性能,保障电力系统的安全、稳定、可靠运行,母线保护中配置CT断线告警、CT断线闭锁等功能。介绍了母线保护中CT断线告警、CT断线闭锁、支路CT断线、CT断线快速识别的原理及判据,该原理及判据在母线保护装置中得到了广泛应用。

During the normal operation of the power system,there is a probability of disconnection of the secondary circuit of the current transformer in the bus protection interval.The disconnection of the secondary circuit of the current transformer will cause the misoperation of the bus differential protection.In order to improve the overall performance of the bus differential protection and ensure the safe,stable and reliable operation of the power system,CT disconnection alarm,CT disconnection locking and other functions are configured in the bus protection,this paper introduces the principle and criterion of CT disconnection alarm,CT disconnection locking,branch CT disconnection and fast CT disconnection in bus protection in detail.This principle and criterion have been widely used in bus protection products.