发电厂送出线重合闸时机的优选与捕捉

Optimal Autoreclosure and its Application Technique

在超高压电力系统中广泛采用三相和单相重合闸来提高电力系统的稳定性，传统的超高压输电线路重合闸采用继电保护跳闸经固定延时起动断路器再次重合的方法。对于瞬时性故障重合成功，但可能造成由于再次重合冲击使摇摆幅度暂时增大。对于永久性故障由于故障的再次冲击可能使电力系统失步。本文经理论分析和仿真计算后提出，对于不同的故障条件存在最佳重合时机。文中给出了优化重合闸的实现方法，经模拟仿真表明，重合时机捉捕正确，并能适应不同的故障前运行条件、故障种类、故障地点远近等，在各种情况下均能实现有效地阻尼系统的摇摆，使系统快速进入稳定运行状态。

Three and single phase autoreclosure are widely used in high voltage systems,to improve system transient stability.However,when a fault occures,the system can suffer from a restrike of the fault if breakers are reclosed at fixed time.When a transient fault occures,the reclosure would be successful,the effect of reclosuring at fixed time is that the system oscillations can be enhanced for a period time. When a permanent fault occurs,the effect could threaten system stability (i. e. loss of synchronization). However,careful choice of reclosure time,could damp the system oscillations for the transient fault,and stabilize the system for the permanent fault.Based on thoroughly theory analysis,the authors raised the optimal reclosure conditions and the optimal autoclosure. Extensive simulation studies,with respect to different operating conditions before fault occurs,different type of faults, and fault locations,show that there exists a optimal autoclosure. Under the optimal reclosure condition,the oscillation of the faulted system will be greatly damped and quickly entre a stable operating condition for both transient and permanent fault. The technique can be realized economically.