Comparison between different real-time harmonic analysis methods for control of electrical machines

This paper proposes a critical analysis of different methods to analyse waveforms in power electronic systems. After having presented classical methods, it is shown that a generalised Park transformation is well suited to the case of electrical drives. This method allows the harmonic analysis of signals. The two signals resulting from the transformation have two DC components and ripple. The two DC components contain the amplitude and the phase of the harmonic selected. As a conclusion, it is shown that the interest of this method is that the undesirable ripple has a frequency at least six times higher than the fundamental frequency. Consequently the response time of the low-pass filter is very attractive. This method seems the more suitable for real-time measurements of the electrical machine drive