Method and device for determining rotating speed of motor and electronic equipment

The invention provides a method and device for determining a rotating speed of a motor and electronic equipment. The method comprises the steps of determining a voltage of the motor under an alpha axis and the voltage of the motor under a beta axis; determining a current of the motor under the alpha axis and the current of the motor under the beta axis; determining a back electromotive force underthe alpha axis and the back electromotive force under the beta axis according to the determined voltage under the alpha axis, the voltage under the beta axis, the current under the alpha axis and thecurrent under the beta axis; according to the determined back electromotive force under the alpha axis and the determined back electromotive force under the beta axis, determining an axis error of the motor, wherein the axis error is used for representing a difference value between an estimated value of the position of the motor rotor and an actual value of the position of the motor rotor; and determining the rotating spe