渝鄂直流背靠背联网工程最后断路器跳闸功能配置

柔性直流输电系统逆变站切除全部交流线路,甩负荷运行,会导致逆变站直流侧及其他部分电压异常升高,危及一次设备安全,因此,在逆变站中配置最后断路器跳闸功能非常必要。结合渝鄂直流背靠背联网工程,提出针对柔性直流输电系统的最后断路器跳闸功能配置方案,并基于RT-LAB实时仿真平台,接入实际控制保护系统和运行人员控制层监控系统,对所提配置方案进行验证。试验结果表明,配置最后断路器跳闸功能后,可保证在交流断路器跳开前或直流电压上升到保护定值前,柔性直流控制系统下发换流器闭锁命令,避免直流侧及交流侧严重过压。

Configuration of Last Breaker Trip Function for Chongqing-Hubei Back-to-Back HVDC Project

The removal of all AC lines and load shedding of inverter station in flexible HVDC system will cause overvoltage at the DC side and other parts in inverter station, which may endanger the safety of primary equipment. Therefore, the configuration of last breaker trip function in inverter station is very necessary. In this paper, based on the Chongqing-Hubei back-to-back HVDC project, a configuration scheme of last breaker trip function for flexible HVDC system is proposed, and is verified by RT-LAB real-time simulation platform which is integrated to the control and protection system and operators monitoring system. The results show that the configuration of last breaker trip function can ensure the locking of converter valves before tripping of the AC circuit breaker or before the DC voltage increasing to the protective setting value so as to avoid serious overvoltage at both AC and DC sides.