| 摘要 |
<p>An electromagnetic compatibility filter circuit of a PWM(Pulse Width Modulation) controller is provided to cut off a ripple current of a motor by applying a pi-type filter of a power unit and an LC filter of a freewheeling unit at the same time. An electromagnetic compatibility filter circuit of a pulse width modulation controller includes a motor(301), a pi-type filter unit(303), a PWM ECU(Electronic Control Unit) unit(309), a motor driver unit(307), and a freewheeling unit(305). The pi-type filter unit filters a noise of the motor and a battery power applied from a vehicle battery. The PWM ECU unit regulates the filter power, converts and outputs a signal having motor driving information, which is applied from a vehicle engine ECU, into a PWM signal. The PWM ECU unit detects an over-current state of the motor. The motor driver unit determines an on/off of a transistor in response to the PWM signal outputted from the PWM ECU unit. If the transistor is tuned on, the freewheeling unit applies the filtered power to the motor. If the transistor is turned off, the freewheeling unit drives the motor consecutively by returning a remaining current of the motor. The freewheeling unit filters and provides the returned ripple current of the motor to the motor driver unit.</p> |
