Fast Gradient Method Based on Dynamic Programming in Model Predictive Control for PMSM Drives

This paper proposes a fast gradient method (FGM) adapted in the stationary reference frame to minimize computational resources of a model predictive control (MPC) of synchronous machines. In the proposed FGM, the projection operation is implemented through the offset voltage injection method rather than the conventional geometrical approach, and gradients are calculated by dynamic programming to reduce the computational cost. Based on the proposed FGM, the MPC framework for the flux regulation is devised, which covers both the space vector modulation and the six-step operation. The validity of the proposed work is verified by simulation and experiments. By the proposed FGM, the computation time of the gradient calculation and projection operation are reduced by 53 % and 11 %, respectively.