Vehicle motor control method and device and vehicle

The invention provides a control method and device for a motor of a vehicle and the vehicle. The vehicle includes an inverter. And the motor is connected with the inverter. The control method comprises the following steps: determining that the motor meets flux-weakening control conditions; according to the direct-axis voltage and the quadrature-axis voltage of the motor and the maximum allowable voltage of the inverter, through I-phase control, the initial flux weakening rotating speed is determined; if the initial flux-weakening rotation speed is smaller than the flux-weakening lower limit rotation speed, determining the flux-weakening lower limit rotation speed as the flux-weakening rotation speed; if the initial flux-weakening rotation speed is greater than or equal to the flux-weakening lower limit rotation speed and less than or equal to the flux-weakening upper limit rotation speed, determining the initial flux-weakening rotation speed as the flux-weakening rotation speed; and if the initial weak magnet