固定串补线路的潜供电流分析及抑制

单相重合闸的成功取决于故障点潜供电流的自熄,而固定串补FSC可改变原有输电线路参数均匀分布的特性,为了单相重合闸成功,分析了串补线路潜供电流中的低频振荡分量的形成机理,同时针对串补线路潜供电流提出了旁路开关联动的抑制措施。仿真证明该措施不但有效降低了串补线路潜供电流,而且减小了断路器暂态恢复电压。该措施在实际运行中取得较好效果。

Secondary Arc in FSC Transmission Lines and Its Restraining Measures

Successful single-phase-reclose is determined by the self-extinguish of secondary arc.The serial compensation has a negative effect on the secondary arc self-extinguishment.Mechanism of low-frequency oscillation component in secondary arc of FSC transmission line is analyzed in this paper.There is energy oscillatory discharge between the serial compensation and the inductance of transmission line.This discharge is a low frequency attenuation component.This component increases the amplitude of secondary arc and decreases the cross-zero times of arc.Some measures are taken in this paper to restrain the secondary arc in FSC transmission line.The secondary arc in serial compensation transmission lines is simulated based on the parameters of Yangcheng project.Modern series compensations protected by MOVs include forced triggered gaps,for fast by-pass if energy dissipation on MOVs or energy rate-of-rise happens to exceed the design values.By-pass by forced triggering of gaps with an external order,initiated by line protection relays,is feasible in the design of series compensations in Yangcheng project.The measures to reduce the secondary arc in serial compensated lines are as follows:use the line protection to trigger gaps,by-pass series capacitors of faulted phase prior to tripping the faulted conductor.The simulation confirmed that the measures not only suppress the secondary arc effectively,but also reduce the transient recovery voltages(TRV)between the circuit breakers.And some problems encountered in the application are also stated.