Converter-Fed Induction Motor Finite Element Analysis With Different Time Steps

Abstract

This paper investigates the losses of a 5-kW converter-fed induction motor. The loss evaluation sensitivity in Finite Element Analysis using different calculation time steps is studied. The motor losses are studied experimentally using a sinusoidal or PWM voltage supply at different operation points. In the experiments, the recorded voltage sampling interval is $1\ \mu\mathrm{s}$ to include all the PWM – induced harmonic content in the data. However, $1\ \mu\mathrm{s}$ time step leads to a long calculation time in time stepping FEA, therefore the data is down sampled to 10 us, 50 and 100 us. The length of the FEA time step is analyzed against the calculation speed and accuracy of the results.