一种输电线路瞬时故障最佳重合闸时刻实用计算方法

Practical Online Calculation of Optimal Reclosing Time for Transmission Line Under Transient Fault

最佳重合闸操作能够快速平息系统摇摆和联络线功率振荡,在提高供电质量和改善系统暂态稳定性方面起着重要作用。为此基于扩展等面积法则(extended equal areacriterion,EEAC)建立了计算最佳重合闸时刻(optimalreclosing time,ORCT)的两机等值系统暂态动能函数,结合广域同步测量系统(wide area measurement system,WAMS)实测数据对发电机角速度进行了滚动预测,在此基础上给出一种仅依赖发电机惯性时间常数和角速度的输电线路瞬时故障最佳重合闸时刻实用计算新方法。算例仿真表明,该方法能够正确计算输电线路瞬时故障最佳重合闸时刻,在线计算时简单实用,计算时间短且误差较小。

Optimal reclosing can fast pacify power system swing and power oscillation in tie line,so it plays an important role in improving both power supply quality and system transient stability.Based on extended equal area criterion（EEAC）,a transient kinetic energy function of two-machine equivalent system is established to calculate optimal reclosing time,and combining with the data measured by wide area measurement system（WAMS） the rolling forecast of generator’s angular velocity is performed.On this basis,a new practical method,which only depends on inertia time constant and angular velocity of generator,to calculate optimal reclosing time of transmission line under transient fault is proposed.Simulation results show that the proposed method can calculate optimal reclosing time of transmission line under transient fault fast and correctly in online way,and the errors of calculation results are small.