Two-time Scale Optimized Model Predictive Cascaded Speed and Current Control for PMSM Drives

Abstract

This paper proposes the two-time scale optimized model predictive speed and current control with for permanent magnet synchronous motor (PMSM). The specific sampling time are assigned to the speed control and current control subsystems respectively based on the characteristics of time scale for different subsystems. The prediction sequence of slow-sampling model during asynchronous sampling period remains the holding state in the conventional model predictive process, which weaken the dynamic performance of system. This paper proposes an estimation method by conducting linear function based on the virtual instants to further improve the predictive accuracy at asynchronous sampling instants. Compared to the conventional method, the improvement of proposed strategy is verified in simulation and experiment.