基于行波理论的滤波器电能质量扰动控制仿真

Simulation of Filter Power Quality Disturbance Control Based on Traveling Wave Theory

传统方法在滤波器电能质量扰动控制时,未对电能扰动的瞬时幅值进行计算,控制效果不佳。为此引入行波理论,分析滤波器噪声产生原因,计算滤波器电能扰动的瞬时幅值,提出了一种新的滤波器电能质量扰动控制方法。分割小波域,在第一个小波域,采用阈值估计法估计期望信号数值大小;在第二个小波域变换含噪信号与小波信号,采用维纳滤波器对信号的小波系数进行估计;通过滤波变换去除含噪信号,获得电能扰动波形的特征参数;根据行波理论计算电能扰动的瞬时幅值,实现对电能质量扰动的准确定位以及类型识别。仿真结果表明,所提方法相比传统方法,具有适应性强、控制效果较好、实时性好等特点。

In the traditional method,the instantaneous amplitude of power disturbance is not calculated,resulting in poor control effect.Therefore,the traveling wave theory was introduced to analyze the reasons of filter noise,so as to calculate the instantaneous amplitude of filter power disturbance.Thus,a new method to control the power quality disturbance was put forward.In the first wavelet domain,the threshold estimation method was used to estimate the ex-pected signal value.In the second wavelet domain,the noisy signal and wavelet signal were transformed.The Wiener filter was used to estimate the wavelet coefficients.Moreover,the noisy signal was removed by the filtering transfor-mation,so that the feature parameters of power disturbance waveform could be obtained.Based on the traveling wave theory,the instantaneous amplitude of power disturbance was calculated,and thus to achieve the accurate location and type recognition of power quality disturbance.Simulation results show that the proposed method has stronger a-daptability,better control effect and better real-time performance than the traditional method.