Effect of carrier frequency and circuit resistance on iron loss of non-oriented electrical steel sheet under single-phase full-bridge PWM inverter excitation

Recently, because of the development of the power electronics technology, PWM inverters have been used to drive motors for achieving precise and energy efficient control. The precise estimation of the increase in iron loss due to high harmonic components of flux, including carrier frequency, is important in the design of motors excited by a PWM inverter. We measured the iron losses of non-oriented electrical steel sheets that were excited by using a single-phase full-bridge PWM inverter and examined the influence of carrier frequency and circuit resistance on the iron losses. We showed that the iron loss increased because of the generation of minor loops when the circuit resistance was high. Therefore, the circuit resistance should be decreased in an actual motor system.