SOFT SWITCHING, PWM CONTROLLER AND METHOD FOR REDUCING TORQUE RIPPLE IN MULTIPHASE DC MOTOR
    1.
    发明授权
    SOFT SWITCHING, PWM CONTROLLER AND METHOD FOR REDUCING TORQUE RIPPLE IN MULTIPHASE DC MOTOR 失效
    用于减少转矩脉动多相DC电动机软开关PWM控制器和控制方法

    公开(公告)号:EP0832513B1

    公开(公告)日:2001-10-17

    申请号:EP96907637.1

    申请日:1996-04-16

    IPC分类号: H02P6/10

    CPC分类号: H02P7/29 H02P6/10

    摘要: A PWM controlled multiphase DC motor apparatus has a multiphase DC motor, a current sensor, and a PWM controller. The DC motor has multiple windings which turn on and off during commutation at a commutation frequency. The current sensor is coupled to sense power supply current flowing in all windings of the DC motor. The PWM controller is coupled to control the DC motor using a PWM signal at selected PWM frequency with variable duty cycle. Using the feedback from the current sensor, the PWM controller maintains approximately constant torque in the DC motor by adjusting the duty cycle of the PWM signal. The PWM controller includes a soft switching circuit which manipulates a voltage used to generate the controlling PWM signal in a manner which causes linear slewing of currents in the windings during commutation. The linear current slewing occurs at a slew rate that is slow relative to the PWM frequency to thereby reduce torque ripple during commutation. The combined features of continuous PWM duty cycle control and linear current slewing during commutation significantly reduces torque ripple at the fundamental commutation frequency, as well as at the first few harmonics. A method for PWM control of a multiphase DC motor is also described.

    DEVICE FOR DRIVING A MULTI-PHASE D.C. MOTOR
    2.
    发明公开
    DEVICE FOR DRIVING A MULTI-PHASE D.C. MOTOR 审中-公开
    装置于驱动的多相DC MOTOR

    公开(公告)号:EP1060561A1

    公开(公告)日:2000-12-20

    申请号:EP99959418.7

    申请日:1999-12-17

    IPC分类号: H02P6/08 H02P6/24 H02P6/22

    摘要: The device for driving a multi-phase d.c. motor (8) includes a multi-phase inverter (11) for supplying drive signals to the windings (2, 4, 6) of the motor. The multi-phase inverter (11) supplies a first and a second drive signal at a time to at least one winding (2) of the motor. The first and the second drive signal flow in opposite directions in the at least one winding (2). The device further has pulse width modulation means (40.1-40.6) for applying a first pulse width modulation to the first drive signal and a second pulse width modulation to the second drive signal. The pulse width modulation means (40.1-40.6) are adapted to vary the pulse width of the pulse width modulation in order to accelerate, actively decelerate or maintain the speed of the motor (8) and to select a direction of rotation of the motor.

    SOFT SWITCHING, PWM CONTROLLER AND METHOD FOR REDUCING TORQUE RIPPLE IN MULTIPHASE DC MOTOR
    3.
    发明公开
    SOFT SWITCHING, PWM CONTROLLER AND METHOD FOR REDUCING TORQUE RIPPLE IN MULTIPHASE DC MOTOR 失效
    用于减少转矩脉动多相DC电动机软开关PWM控制器和控制方法

    公开(公告)号:EP0832513A1

    公开(公告)日:1998-04-01

    申请号:EP96907637.0

    申请日:1996-04-16

    IPC分类号: H02P6 H02P7

    CPC分类号: H02P7/29 H02P6/10

    摘要: A PWM controlled multiphase DC motor apparatus has a multiphase DC motor, a current sensor, and a PWM controller. The DC motor has multiple windings which turn on and off during commutation at a commutation frequency. The current sensor is coupled to sense power supply current flowing in all windings of the DC motor. The PWM controller is coupled to control the DC motor using a PWM signal at selected PWM frequency with variable duty cycle. Using the feedback from the current sensor, the PWM controller maintains approximately constant torque in the DC motor by adjusting the duty cycle of the PWM signal. The PWM controller includes a soft switching circuit which manipulates a voltage used to generate the controlling PWM signal in a manner which causes linear slewing of currents in the windings during commutation. The linear current slewing occurs at a slew rate that is slow relative to the PWM frequency to thereby reduce torque ripple during commutation. The combined features of continuous PWM duty cycle control and linear current slewing during commutation significantly reduces torque ripple at the fundamental commutation frequency, as well as at the first few harmonics. A method for PWM control of a multiphase DC motor is also described.