초록 ▼

Methods and apparatuses are provided for use in driving a multiple-phase brushless motor. The methods and apparatuses include generating a slewed phase control signal for each phase of the motor. The slewed phase control signals are substantially proportional to a speed control signal during non-tra

Methods and apparatuses are provided for use in driving a multiple-phase brushless motor. The methods and apparatuses include generating a slewed phase control signal for each phase of the motor. The slewed phase control signals are substantially proportional to a speed control signal during non-transitioning periods, and are slewed from one state to the next state over time during transitioning periods. The transitioning periods being associated with a commutation point. The slewed phase control signals are used to generate pulse width modulated (PWM) driving signals, for each phase of the motor. Thus, the shape of the resulting PWM driving signal will include additional PWM pulses during the transitioning period that provide for a trapezoidal shaping of the current supplied to each of the phase coils in the motor. The result is that torque ripple is reduced because the overall current applied to the motor and the torque resulting therefrom will tend to be more constant during commutation.

대표청구항 ▼

[ What is claimed is:] [1.] A method for driving a multiple-phase motor, the method comprising:generating a pair of slewed phase control signals that are opposite in polarity, the slewed phase control signals representing at least two operating states, wherein a first one of the operating states is

[ What is claimed is:] [1.] A method for driving a multiple-phase motor, the method comprising:generating a pair of slewed phase control signals that are opposite in polarity, the slewed phase control signals representing at least two operating states, wherein a first one of the operating states is directly proportional to a speed control signal, wherein the phase control signals switch between the operating states in response to a commutation event, the commutation event having a transitioning period associated therewith, wherein the phase control signals are slewed between the operating states during the transition period;generating a pulse width modulated (PWM) phase driving signal for each of the slewed phase control signals; andsupplying the PWM phase driving signals to the motor.