A simplified model predictive control (S-MPC) for open-winding permanent magnet synchronous motor system fed by two isolated power sources is proposed in order to remove the complex tuning work of weighting factors and reduce the calculation burden in the conventional MPC. Control constraints torque and flux in the conventionalMPC are converted into an equivalent flux vector for the purpose of eliminating the weighting factor in the cost function. Moreover, a novel prediction strategy and a fast voltage selection scheme are presented to reduce the system calculation burden. As a result, the optimal voltage is selected through only twice evaluations. Furthermore, a switching states distribution strategy is introduced to reduce the switching frequency of a dual inverter. Comparative experiments are conducted to verify the effectiveness of the proposed method.