基于小波变换的单频时变电压闪变检测仿真研究

Simulation Study on Single-frequency Time-varying Voltage Flicker Detection Based on Wavelet Transform

电压波动与闪变是衡量电力系统电压质量的重要参数,而小波变换以其优异性在电压闪变检测中得到了越来越多的应用。为了验证小波变换在电压闪变检测方面的有效性与可行性,搭建了含单一闪变分量的电压闪变信号模型。采用小波变换对电压闪变信号的检测进行了仿真分析,并将仿真结果与基于平方检测法的仿真结果进行了对比分析。仿真结果表明,小波变换不仅能够检测出电压闪变分量的幅值与频率信息,而且能够根据小波变换的模极大值确定电压闪变发生与结束的时刻,基于小波变换的检测效果优于基于平方检测法的检测效果。

Voltage fluctuation and flicker are important parameters for measuring voltage quality of the electric power system.Wavelet transform has found more and more application in voltage flicker detection because of its excellent performance.In order to verify the effectiveness and feasibility of wavelet transform in voltage flicker detection,a voltage flicker signal model with a single flicker component was established in this paper.Detection of voltage flicker signal was simulated through wavelet transform,and the simulation results were compared with those based on the square detection method.Simulation results showed that wavelet transform could not only detect the amplitude and frequency information of the voltage flicker component,but also determine voltage flicker start and end time according to the modulus maximum of wavelet transform.The detection effect based on wavelet transform was better than that based on square detection method.