Model predictive torque control for permanent magnet synchronous motor based on dynamic finite-control-set using fuzzy control

Abstract

Aiming at the problem of fixed candidate voltage vector (VV) in conventional finite-control-set (FCS) model predictive torque control (MPTC) of permanent magnet synchronous motor (PMSM), fuzzy control is use to determine dynamic candidate VVs based on effects of the value and angle of applying VV on stator flux and torque. The inputs of fuzzy controller are errors of stator flux and torque and outputs are 3 candidate VVs. Simulation results show compared with conventional FCS-MPTC, the proposed strategy can decrease stator flux and torque’s ripples and calculation burden of MPTC, but it will increase average switching frequency. In order to decrease average switching frequency, zero VV is also used as candidate VV, but it will decrease dynamic torque response. Thus the method that zero VV is used only at steady state is given. Simulation results show the control performance of the system remains basically unchanged and the average switching frequency is reduced.

Keywords

• Permanent magnet synchronous motor
• Model predictive control
• Fuzzy control
• Finite-control-set
• Candidate voltage vectors