| 摘要 |
PURPOSE:To suppress the power consumption by a suitable motor drive current when the motor is operated in a highest rotating area by controlling the switching of a fundamental power transistor based on a motor input current and the transistor switching time. CONSTITUTION:A motor counter-electromotive voltage estimating unit (g) inputs a motor position current and a motor angle position, and estimates the counter- electromotive voltage of a motor (a) by considering a maximum angle to be decided according to the physical characteristics of the motor (a). A fundamental switching time calculator (h) inputs a motor power source voltage and the motor counter-electromotive voltage, and decides a fundamental switching time of a power transistor (b) according to the previously measured impedances of the motor (a) and the transistor (b). A power transistor switching controller (i) controls the switching of the transistor (b) based on the motor input current and the transistor switching time. |
