Investigation into core losses due to harmonic voltages in PWM fed induction motors

The paper focuses on mechanisms of harmonic core losses due to PWM characteristics. The relationship between modulation depth, particularly at higher values of PWM strategies, and loss characteristics are discussed. The PWM voltage spectra at higher modulation depth are examined for interpreting core losses associated with the interaction between individual harmonic voltages and machine features. The investigation into harmonic core loss based on no-load tests with minimized rotor copper loss and rotational loss has been made. The experimental results have shown that the increment of core losses due to PWM harmonic voltages is significant compared to a sinusoidal supply and the modulation depth has significant effect on machine core losses