This digest presents a robust model predictive control (MPC) based fault tolerant control of a six-phase permanent magnet synchronous motor (PMSM) under single-phase open circuit fault without control structure reconfiguration. In postfault operation, the calibrated voltage vectors are no longer stable but dependent on machine parameters. Therefore, two causes of the prediction error, namely the voltage vectors calibration and the predictive model are jointly considered in the postfault operation. The parameters including the stator resistance and inductance in the fault condition is estimated online using extended Kalman filter. In this way, the robustness of the fault tolerant control scheme in two aspects, including the voltage vector calibration and the predictive model, against the parameter mismatch is enhanced. Experimental results are presented to validate the feasibility of the proposed method.