Performance Assessment of FCS-MPCC and DPCC for PMSM Drives Under Matched Average Switching Frequency Conditions

Finite Control Set Model Predictive Current Control (FCS-MPCC) and Deadbeat Predictive Current Control (DPCC) for Permanent Magnet Synchronous Machine (PMSM) drives are comparatively evaluated in this study. To ensure a fair comparison, both control techniques are evaluated using the same machine model and under a variety of operating conditions, including different speed and current commands. The FCS-MPCC method operates with a variable switching frequency, whereas the DPCC method has a constant switching frequency. Therefore, the average switching frequency of the FCS-MPCC method is measured for each operating condition and used to determine the appropriate switching frequency for the DPCC method. This enables a consistent comparison to be made under equivalent switching effort. A comparative analysis is conducted across multiple operating points in order to capture the performance variations of the two control strategies under different speed and current commands. Simulation results indicate that, under identical switching frequency and sampling constraints, the DPCC method generally achieves lower current tracking errors and reduced current Total Harmonic Distortion (THD) compared to the FCS-MPCC method. However, it has also been revealed by the results that the performance of FCS-MPCC is dependent on the selected sampling period. A thorough investigation of the effect of sampling time reveals that reducing the sampling interval greatly improves the current tracking accuracy and harmonic performance of the FCS-MPCC. When the sampling period is small enough, FCS-MPCC can perform comparably to, or even better than, DPCC. However, this comes with a higher switching frequency and more computational burden. Overall, the findings emphasise the trade-off between control performance, switching effort, and implementation complexity. The selection of predictive current control strategies for PMSM drives can be approached via these comparative studies.