Assessing harmonic impedance by synchronously layered distortion waves based on wavelet

In this paper, a method assessing harmonic impedance by synchronously classifying distortion waves is proposed, which is based on the distortion quantity method, a simple and effective means. However the method is based on the Fourier transform, which can just precisely analyze the signals whose cycle is integer times as broad as that of fundamental wave. With sampling windows widening, the variations of distorted signals in a fundamental period are weakened. Moreover, the higher harmonic order is, the lower distinguish ability, and, as a result, the assessment accuracy becomes bad. Considered its prominent localization both in time-domain and in frequency-domain, wavelet is used to the field of assessing harmonic impedance for the first time.