110kV终端变电站小电源故障解列实例研究

Study on Disconnection of Small Power Source Fault in 110 kV Terminal Substation

带小电源的终端变电站在发生进线瞬时故障时,一般由故障解列装置在重合闸延时时间内迅速将其所带的小电源解列,再进行重合。而贺州电网带小水电的110 kV金牛变电站在发生进线故障时,却出现了故障解列装置不动作的现象,导致进线断路器无法重合,全站失压。通过故障录波文件对110 kV金牛变电站发生的几次故障解列装置未及时动作情况作出了分析,分析指出由于电压和频率的波动导致装置发生了功能闭锁,并针对这一现象提出了改进方法和防治措施。

When transient fault occurs in transmission line,the small power source of terminal substation will be rapidly broke down by fault disconnection apparatus in the delay time of reclosing,and then it is reclosed.But when the breakdown of transmission line happened on 110 kV Jinniu Terminal Substation with small hydropower in Hezhou power grid,the phenomenon that there is no action of fault disconnection apparatus occurred,which causes the circuit-breaker cannot be reclosed,and the entire substation lost the voltage.Through fault record files,the situation that fault disconnection apparatus can not act in time for several times occurring in 110 kV Jinniu Terminal Substation is analyzed.It is pointed out that the function of fault disconnection apparatus is blocked because the fluctuation of voltage and system frequency.At last,the improvement methods and prevention measures are proposed.