A Simple Model Predictive Current Control for PMSM Drives Based on Harmonic Current Extraction

In some special applications, due to operating conditions, a relatively low switching frequency (LSF) is required to reduce the power losses due to switching actions. However, the total harmonic distortion (THD) rate of the motor current is elevated at LSF. Therefore, to reduce the increase in current harmonics due to the decrease in switching frequency, a simple model predictive current control (MPCC) for permanent magnet synchronous motor (PMSM) drives based on harmonic current extraction at LSF (LSF-HCE-MPCC) is proposed. First, the method designs a current harmonic separator with a simple structure; then, the predicted current harmonic component expression can be obtained by simple calculation. Finally, it is introduced into the cost function to balance the effect of current harmonics on the whole system. The feasibility of the LSF-HCE-MPCC is verified experimentally.