Investigation and comparison of system efficiency on the PMSM considering Nd-Fe-B magnet and Ferrite magnet

This paper studies the influence of permanent magnet on the total system efficiency of permanent magnet synchronous motors (PMSM). Two PMSM with Nd-Fe-B and Ferrite magnets which have same back-EMF and output power have been designed. First, the dynamic simulation is performed with these two motors' parameters. The current waveforms and switching losses of transistors can be evaluated. And then, by means of the obtained current waveforms and a series of numerical methods, the iron losses of these two motors will be calculated. Finally, comparing the sum of the switching losses and iron losses, the result can be used to reflect the influence of the magnet on the total motor system efficiency.