Optimal control solutions for PMSM drives: A comparison study with experimental assessments

In this paper, a general optimum control for power converters and drives is proposed. The proposed optimum control will select an optimum voltage vector from the whole hexagonal plane, leading to the best control performance fulfilling a predefined performance index. With the proposed concept, two subsolutions, i.e., both continuous and discrete solutions, are derived and unified in the frame of optimum control. The continuous solution utilizes the averaged continuous-time model of the system and is capable of dealing with multiple system constraints, showing good performance with less calculation efforts, while the discrete solution takes the finite set of the power converter switching vectors into consideration and the state transition of the system can be predicted with a chosen vector. Both methods require less calculation efforts compared with the well-known finite-control-set model predictive control method, which makes it very suitable for practical realizations. Finally, as a case of study, the proposed concept is tested at a current-controlled 3-kW surface-mounted permanent magnet synchronous motor drive under different scenarios. The experimental results validate the effectiveness of both solutions.