【摘要】 在暂态电流信号小波分析结果的基础上,借鉴熵权的概念,给出了小波熵权的定义,提出一种利用高频暂态分量的小波熵权实现故障选相方法。该方法直接利用电流互感器的暂态高频电流,使用小波提取暂态信号特征,对提取的信号特征计算其沿尺度分布的权重,得到暂态信号的小波熵权,由此构造故障选相判据进行选相。基于EMTDC和MATLAB环境,利用该方法对某一典型500kV线路进行各种故障类型选相的仿真分析,分析表明该方法具有高速、准确的特点,且不受过渡电阻、故障时间及故障位置等因素的影响,具有一定的实用价值。更多还原

【Abstract】 A definition of wavelet entropy weight is proposed on the basis of both the result of transient current signal wavelet analysis and the idea of entropy weight. By using this definition and high frequency transient signal, a fault phase selecting method is represented. This method takes the transient high-frequency current of current transformer as its signal, and uses wavelet to pick up signal’s feature. Calculating this feature by its scale distribution weight, transient signal wavelet entropy can be obtained. Based on above work, a fault phase selecting criterion is presented. All faults of a typical 500 kV line under EMTDC and MATLAB by using the method are simulated. The result shows that this method is quick, accurate and free from the disturbance of transition resistor, fault time and location.更多还原