Patent ID: 6998814

Claim:
A method for measuring the electromotive force constant of a motor, comprising steps of: enabling the motor to rotate in single phase mode; measuring phase voltages of the motor when the motor rotates to a predetermined velocity; and obtaining the electromotive force constant of the motor according to the relationship of the phase voltages and the predetermined velocity, wherein the relationship of the phase voltages and the predetermined velocity is v ω ⁡ ( t ) = K emax ⁢ ⁢ cos ( θ r + 2 ⁢ ⁢ π 3 ) ⁢ ⁢ ω r = ( v a + v b - 2 ⁢ v c - 3 ) ⁢ ( P 2 ) , wherein v a , v b , v c are the phase voltages of the motor, ω r is the velocity of the motor, K emax is the electromotive force constant of the motor, θ r is the electrical angle of the rotator of the motor, P is the number of the magnetic pole of the rotator magnet.