Real-time implementation and comparison of time-varying harmonic measurement methods

Harmonies are an important issue in electric power systems. Therefore, real-time techniques to estimate and quantify harmonies and other indices directly related to waveform distortion are receiving increased attention. This paper presents and compares the outcome of three measurement techniques used to obtain the harmonic content of current and voltage measurements. For this study, Fast Fourier Transform (FFT), a model-based technique and a new approach based on the real wavelet transform of the analytic representation of distorted power signals are considered. The proposed methods are verified by real measurements on the in-house developed prototyping measuring platform. A DSP performance analysis is also given.