AUTOMATIC OPENING/CLOSING DEVICE FOR VEHICLE

摘要

PROBLEM TO BE SOLVED: To improve followability of an opening/closing body to a target speed by improving a regenerative braking force of an electric motor.

SOLUTION: The electric motor that drives a sliding door so as to be opened or closed is connected to an H-bridge circuit. The H-bridge circuit executes drive control and regenerative braking control of the electric motor. Speed control is executed so that an opening/closing speed of the sliding door becomes identical to the target speed by PWM-controlling a switching element of the H-bridge circuit. When the opening/closing speed of the sliding door becomes faster than the target speed, the electric motor is subjected to regenerative braking while setting a carrier frequency of a PWM signal lower than that of when driving the electric motor in order to improve the regenerative braking force of the electric motor. The carrier frequency of the PWM signal is reduced while increasing a duty ratio in order to further improve the regenerative braking force of the electric motor.

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