高压输电线路双端暂态电压保护新算法

Novel Protection Criterion for High Voltage Transmission Line Based on Two-end Transient Voltage

研究了利用高压输电线路两端暂态电压信号实现保护的方法。分析了区内和区外故障时线路两端高频暂态电压信号的差异,推导出暂态电压含量比和暂态电压奇异度比。利用信号的小波变换结果计算出以上比值,并由此构造出了双端暂态电压保护判据,同时给出保护定值的设定原则。利用不同位置和类型故障的仿真对算法进行了验证,算法判别准确可靠,选择性好。

The protection method for high voltage transmission line using two-end voltage transient signals is discussed in the paper. The differences of high frequency transient voltage signals at the two ends of the transmission line are analyzed under both in-zone fault and out-zone fault. And then the transient voltage content ratio and transient voltage singularity ratio are deduced with wavelet transform results of the voltage transients. Based on the ratios, two-end transient voltage protection criterion is obtained. Meanwhile, the principles of protection settings are given. Simulations under different fault locations and different fault types are carried out, which prove the accuracy and selectivity of the proposed protection criterion