Estimation of core losses when the flux waveform contains the fundamental plus a single odd harmonic component

This paper examines the behaviour of the core losses in thin laminations when the flux density waveform is highly distorted at peak flux densities of up to 2.0 T. It is shown that the presence of harmonics can increase the loss significantly over the value that exists when the flux density waveform is purely sinusoidal. A simple method that corrects the eddy current component of core loss for the effects of flux harmonics is used to estimate the total loss due to a distorted waveform. Provided the waveform does not contain harmonics greater than the 5th, it is shown that such a method of estimation yields acceptable results for the distortion levels encountered in practice.