Abstract: The external rotor of permanent magnet hub motor is usually directly connected to the rim tire, which has a larger rotational inertia than the inner rotor permanent magnet drive motor; at the same time, the speed response of the permanent magnet hub motor obviously lags behind the load change. Therefore, under complex operating conditions, the rotational speed of the permanent magnet hub motor drive system is unstable, and the travel path of the electric vehicle is prone to deviation. In order to solve this inherent technical problem of electric vehicles under hub drive, this paper proposes an unweighted cost function model predictive torque control (MPTC) strategy with the magnetic chain as the only constraint, which realizes the stable operation of electric vehicles under complex and variable dynamic working conditions. The cost function proposed in this paper unifies the torque and stator magnetic chain amplitude constraints into the optimization of the stator magnetic chain vector, eliminates the rectification of the weighting factor, and improves the response speed of the hub motor under complex operating conditions. At the same time, the stator magnetic chain at the instant of switching between the effective voltage vector and the zero voltage vector is introduced. This serves as the criterion for selecting the optimal voltage vector, reducing the torque and stator magnetic chain pulsation, and improving the accuracy of hub motor speed control. The experiment verified the correctness and effectiveness of the control method.