Induction Motor Operation With Non-Sinusoidal Impressed Voltages

The usual procedure in considering the operation of induction motors has been to neglect the effect of harmonics. Although in most instances this gives results which are sufficiently accurate, the question of how much these effects are or how much is being neglected has yet to be answered in electrical engineering literature. In this paper an attempt is made to answer this question. It is also devoted largely to a statement of results with only such explanation as space permits. The conclusions are that, with harmonics of 10 per cent or less, the harmonics produce an insignificant effect, for all types of induction motors and for all conditions of operation, except for the no-load condition. In this case, significant but not serious increases of I²X occur. Also lightly loaded induction motors may be counted on to smooth out the impressed electromotive force wave.