Dynamic Current Trajectory Tracking Strategy with Optimized Overmodulation Method for Permanent Magnet Synchronous Motor Drives

Deadbeat predictive current control (DPCC) can track the command with a two-sample step response. However, voltage insufficiency is common during abrupt torque changes, and the current command tracking performance is inevitably degraded. To address this issue, an optimized overmodulation method is proposed in this paper. By predicting the current hexagon in the subsequent switching period, the crossing point between the current hexagon boundary and the expected current trajectory is determined as an optimized current reference. The purpose is to mitigate the current trajectory drift in the overmodulation zone, thus ensuring optimal trajectory tracking performance and voltage utilization. The solution of the crossing point is solved by the dichotomy due to the randomness of the expected trajectory. By combining DPCC with the proposed optimized overmodulation method, dynamic current reference optimization and deadbeat response in the overmodulation zone are achieved. The analysis results are compared with the DPCC with a traditional constant saturation limitation method. The experimental results validate the effectiveness of the proposed method.