摘要
介绍了至今为止国家标准中规定的各项电能质量指标的计算方法,提出了一种将小波变换与短时傅里叶变换相结合的方法对电能质量的暂态和稳态问题监测的方法,其中小波变换选用Mallat算法,短时傅里叶变换窗函数选用Hanning窗。利用小波变换Mallat算法对暂态电能质量问题进行实时监测,并且区分稳态扰动与暂态扰动,再对各频段进行短时傅里叶变换去分析,从而能够很好的对时域和频域进行分析。
It introduced the national standards for electricity power quality algorithm. The dissertation puts forward a method to test for electricity power quality. The method is the combination of the wavelet and the short-time Fourier transform. The wavelet transform selected the algorithm of Mallat and the short-time Fourier transform＇s function of the window is the Hanning By using wavelet transform the algorithm of Mallat for transient power quality problems for real-time monitoring. It distinguished between steady-state disturbance and transient disturbance. To each frequency band for short-time Fourier transform to analysis, which can be good to the time and frequency domain analysis. MATLAB simulation results show the accuracy and validity of this method.
