| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor controller which exhibits lower loss and is capable of controlling a motor over a range wider than that with direct-current voltage control methods, based on boosting chopper. SOLUTION: The motor controller comprises a rectifying circuit which rectifies alternating-currents; smoothing capacitors formed by connecting capacitors in series; an inverter; and a bidirectional switch placed between the motor and the alternating-current side of the rectifying circuit, and the point of series connection of the smoothing capacitors. In a first operation mode, the pulse width of the inverter is controlled, and the speed of the motor is thereby controlled. In a second operation mode, the on-phase of the bidirectional switch to alternating-current voltage is controlled, and the motor is thereby controlled. Thus, direct-current stage voltage is controlled without use of a boosting chopper. As a result, the switching loss of a boosting chopper is eliminated. |
