Harmonic analysis of induction motor flux density waveform using wavelets in speed control application

The lack of a numerical model in the literature for harmonic analysis of the air gap flux density waveform in an induction motor speed control application, by changing pole numbers, inspires this study. One of the methods for speed control of an induction motor is to change the number of poles of the stator winding. The change in the pole numbers introduces additional harmonics in the air gap flux density waveforms which are harmful to machine performance as well as equipment connected to it. The wavelet packet transform is used to quantify the harmonics in the flux density waveform. The results are useful in the design and development of both motor and drive diagnosis systems. The originality and significance of this research is to enable researchers to choose a proper induction motor in speed control applications by changing pole numbers.