Incremental Deadbeat Predictive Current Control Strategy With Disturbance Observer for PMSM Drive Systems Using Four-Leg Inverters

Deadbeat predictive current control (DPCC) has been implemented in four-leg inverters to obtain faster dynamic response and higher system bandwidth, and effectively reduce the machine torque ripple caused by current tracking error after open-phase fault. However, DPCC is a kind of model-parameter-sensitive control method, so inaccurate model parameters may cause deviations in the current prediction and reduce control performance. To address this issue, an incremental deadbeat predictive current control strategy with sliding mode disturbance observer (IDPCC+SMDO) is proposed in this article. Detailed studies are carried out to validate the parameter robustness of the proposed method. Initially, the permanent magnet synchronous motor model with connected neutral point is conducted, followed by the parameter sensitivity analysis of conventional DPCC method. Subsequently, an incremental prediction model is established to eliminate the effects of permanent magnet flux linkage mismatch on the prediction results. Furthermore, a sliding mode observer is designed for the compensation of disturbances and uncertainties caused by inductance and resistance mismatches. Finally, the effectiveness of the proposed IDPCC + SMDO method is verified by comprehensive simulations and experiments. The results demonstrate that the proposed method can suppress the negative impact of parameter mismatches on the control performance in both healthy and open-phase fault-tolerant operation modes.