| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a compact, low-cost drive unit for automatic transmissions that can be driven by a motor without any sensors. <P>SOLUTION: The drive unit for automatic transmissions is provided with: a means for leading a rotation position from the detection signal of a stroke sensor for driving a motor by using the stroke sensor for detecting the amount of stroke in an actuator; a means for detecting commutation timing from the waveform of a motor current flowing to the motor for driving the motor; and a means for calculating the speed of the motor by using an applied voltage in an inverter for energizing the motor, a motor current, inductance in the motor, wound resistance, and an induced voltage constant. Thereby, a rotational angle is derived by using the stroke sensor for detecting the amount of stroke in the actuator in sensorless drive without any rotation position detectors of a rotor, and by detecting the commutation timing by the current value of the motor, torque control from a zero speed (in stop) can be performed. <P>COPYRIGHT: (C)2004,JPO</p> |
