Deadbeat predictive current control of permanent magnet synchronous motor with current harmonics minimization

Deadbeat predictive current control (DBPCC) based on space vector modulation (SVM) has been widely used in the high-performance control of permanent magnet synchronous motor drives, due to its simple principle, fast dynamic response and fixed switching frequency. However, the conventional DBPCC adopts a single 7-segment vector sequence, which results in relatively large current harmonics at high modulation indices such as high speed and heavy load. The prior studies have proved that the current harmonics of bus-clamping space vector pulse width modulation are smaller at high modulation indexes, but the choice of optimal vector sequence is complex and it is only verified under the conditions of open-loop operation. After deriving the analytical expressions for the current harmonics of four voltage vector sequences, this paper proposes a variable-sequence-SVM DBPCC. According to the modulation index, this method online selected the optimal voltage vector sequence with minimal current harmonics, which is simple and effectively reduces the current harmonics. Simulation and experimental results confirm that, compared to conventional DBPCC based on the fixed vector sequence, the current harmonics and total harmonic distortion (THD) of the proposed method are minimized at full modulation indices. The current THD can be reduced by more than 30% when the modulation index is above 0. 92. © 2023 Editorial Department of Electric Machines and Control. All rights reserved.