Rotor power loss in a PM SM by calculation, simulation and measurements, mutual verification of methods

The subject of the paper is the comparison of four complementary methods of the rotor loss estimation in a PM SM, supplied by a PWM voltage source. An ANSYS based finite element model produces values of W, the magnetic energy stored, and P, the rotor losses. On analytical level the machine is represented by a parallel two elements equivalent circuit for each voltage harmonic. Its parameters are estimated using P and W values. Finally, the eddy current losses representation in the ANSYS code is verified for magnets under study by direct losses measurements. The calculation results are compared with some measured values resulting from analysis and harmonic decomposition of the machine total losses.