A three-vector model predicting torque control of permanent magnet synchronous motor with a fixed weight coefficient

Abstract

The difficulty of adjusting the weighting coefficients of the cost function in traditional model predictive torque control is addressed by proposing a fixed weighting coefficient three-vector model predictive torque control (FWC-MPTC) strategy. The strategy applies three voltage vectors in a control period. The first voltage vector is selected by a fixed coefficient cost function, the second and third voltage vectors are determined by a cost function that includes only torque and flux, and the third voltage vector is no longer just a traditional zero vector. In addition, to solve the problem of poor disturbance immunity of the speed loop PI controller, an active disturbance rejection controller (ADRC) is introduced in the speed loop, and the error non-linear function in the controller is rewritten into a smoother new function. The proposed control strategy reduces the torque and speed fluctuation of the traditional three-vector model predictive control (TTV-MPTC), improves the robustness of the system, avoids the difficulty of adjusting the weight coefficient in the traditional cost function, and reduces the computational complexity of the cost function.