复龙站阀水冷流量保护跳闸隐患分析及处理

Analysis and Solution of Valve Cooling System Flow Protection Trip in Fulong Converter Station

阀内水冷系统安全稳定运行对于保证特高压直流输电系统的可靠运行具有重大意义。介绍了复龙换流站验收期间,通过阀内水冷主泵功能试验时发现低流量保护跳闸的重大隐患,分析了保护跳闸的主要原因是:变频器低电压控制功能设置不当、启动备用主泵的时间过长、低流量跳闸二段定值设置过高、站用电400V备自投时间定值设置过长。现场经过优化变频器控制功能、阀内水冷控制系统软件、阀内水冷低流量跳闸二段定值、400V备自投时间定值,有效解决了跳闸隐患,提高了特高压直流输电系统的运行可靠性。

Valve cooling system is very important in UHVDC transmission system.A valve cooling system low flow protection trip occurs during Fulong converter station in functional acceptance test,the reasons caused the failure are: the setting of undervoltage control of frequency converter is not correct,the time of starting redundant pump is too long,the setting of low flow trip protection is too high,the time of setting 400V auto-switch system is too long.Then four solution methods are given to prevent low flow protection trip failure.