ENERGETIC BEHAVIOR OF SOFT-MAGNETIC MATERIALS IN THE CASE OF INVERTERSUPPLY

The energetic behavior of several samples of soft magnetic materials e xcited by inverter have been analyzed. The authors dealt with the iron loss increase due to the nonconventional voltage supply such as inver ter-fed induction motors. Square-wave and PWM inverter voltages have b een selected as the excitation waveforms for the samples under test. E xtensive experimental results on good-quality nonoriented silicon stee l, medium and high-quality grain-oriented silicon steel, and amorphous alloy would cores are presented. Furthermore, a detailed description of the testing procedure is reported. The results allow one to estimat e the percentage of the iron loss increase with the nonsinusoidal supp ly. The comparison with the results obtained with the sinusoidal suppl y gives useful indications to the electromagnetic device designers abo ut the ''derating factor'' to be used for devices fed by static power sources.