Minimization of common-mode voltage for matrix converter-fed permanent magnet synchronous motor system with model predictive control

Purpose – To eliminate common-mode voltage (CMV), this paper aims to use rotation vectors as an alternative vector set for model predictive control (MPC). Design/methodology/approach – Aiming at the problem of large current harmonics and torque fluctuations caused by uneven distribution of rotation vectors, this paper uses virtual vectors synthesized by rotation vectors to expand the control set, and synthesizes 2, 1 or 0 virtual vectors under different input voltage phase conditions, so that the overall distribution of alternative vectors tends to be uniform. Findings – It can be seen through experiments that the steady-state performance of MC-PMSM system under the proposed MPC method is better than that of conventional MPC using rotation vector, and the elimination of CMV is also achieved. Originality/value – MPC is commonly used for permanent magnet synchronous motor systems fed by various converters. For PMSM systems fed by matrix converters (MCs), the active vectors and zero vectors of MC are mainly used as alternative vector sets. However, this creates CMV, which negatively affects system stability and security.