城市轨道交通35kV供电系统允许式电流选跳保护分析

Analysis of Selective Trip Protection for Urban Rail Transit 35 kV Power Supply System

针对我国城市轨道交通35 kV供电系统通常采用的闭锁式电流选跳保护存在保护配置复杂及发生过误动作等问题,提出一种允许式电流选跳保护。通过分析其在不同类型故障时的动作情况,阐述其动作逻辑与原理。该电流选跳保护借助数字通信保护技术实现电流选跳保护之间的信息交换,通过不同类型的允许信号逐级加速,实现故障点相邻若干级保护的动作时间配合,有选择性地快速切除故障,使可靠性更高且保护配置简单。

Since the complex protection configuration and malfunction problems of the blocking current selective trip protection adopted widely in urban rail transit 35 kV power supply system in China,a selective trip protection method is proposed.Through analyzing the performances of the new method in different fault conditions,its operational logic and working principle are expounded.The new protection method supports the information exchanges between different current selective trip protections based on digital communication protection technology,ensures the escalated acceleration through different types of permissive signals,also realizes the action time coordination between levels of protection adjacent to fault points,removes the fault selectively and quickly,solves the complex protection configuration and malfunction problems effectively.