【摘要】 输电线路继电保护中的高频保护故障信号在传输过程中存在延时与衰耗,导致信号偏移及能量损耗;另外故障发生点的不同,使得故障电流产生相位差。小波变换所具有的时频局部化特性非常适合对复杂信号进行多分辨率分析以及奇异点检测。利用db小波对相差高频保护中的故障电流进行分解并以此识别内部、外部故障。通过Matlab进行实例仿真,仿真结果证明了该方法的可行性和有效性。更多还原

【Abstract】 In HF (High-Frequency) protection of transmission line relay protection, fault signal will be delayed and attenuated in the transmission process, which will lead to signal excursion and energy consumption. Furthermore, fault current will have phase differential because faults occur at different palaces. With the characteristic of time-frequency location, Wavelet transform is very suitable for complex signal to make multi-resolution analysis and singularity detection. Db Wavelet is used to decompose the fault current of phase differential HF protection and then recognize the interior and exterior fault. Simulation is made through Matlab and the Simulation results show the method is feasible and effective.更多还原