侯家湾变电站低频低压减载装置的改进

Improvement of low-voltage and low-frequency load shedding devices in Houjiawan transformer substation

为解决侯家湾变电站在110kV双母线分列运行(不同系统供电)时,一段母线频率实际下降到低频自动减载动作定值而低频低压自动减载装置不发出跳闸命令而只发出装置异常告警的问题,从低频低压自动减载装置的动作条件及装置发出频率或电压异常信号的原理入手,分析了侯家湾变电站低频低压自动减载装置拒动的原因,指出了侯家湾变电站在110kV双母线分列运行时,低频、低压自动减载装置不能适应同一变电站分列运行的母线由不同系统供电的运行方式造成装置据动。提出了现有装置的适应这种分裂运行方式的改进方案。经严格的测试及挂网运行验证表明改进后的装置完全适用于双母并运、双母分列运行(同一系统)、双母分列运行(不同系统)等多种方式。

In order to solve the problem that the low frequency and low voltage load shedding devices of Houjiawan transformer substation send out anomalous signal instead of trip signal when the frequency of 110kV bus falls below the threshold value under bus splitting operation condition（supplied from different system）, based on the low frequency and low voltage load shedding logic and frequency/voltage anomalous signal sending principle, this paper analyzes the reasons that the low frequency and low voltage load shedding devices in Houjiawan transformer substation reject action, and points out that the devices do not adapt to the condition that the 110kV split buses supplied from different systems. What＇s more, the paper puts forward the measurements of improving the devices to adapt to the bus splitting operation mode. Strict tests and practice experiments validate that the devices are applicable to all kinds of operation conditions such as double bus apposed operation mode, duplicate-bus segmentation mode （supplied from one system or from different systems）.