Answer 7—Because the magnetizing current is basically current through an inductor, the waveform is the integral of the voltage waveform. If the voltage drive waveform is a sinusoid, the current waveform is also a sinusoid, delayed by 90°. If the drive waveform is a square wave, the current waveform is a triangle wave.

Note however that the in-phase primary current caused by loading the secondary will be a square wave, so the net current in the primary winding will be a combination of both waveforms.

Contributor: David Tweed