| 摘要 |
An inverter apparatus includes a rotor position/speed measuring block (8) for measuring the position/speed of a rotor from a terminal voltage of a motor (4), a speed control block (10) for controlling the motor speed to a target speed, a power application period setting block (11) for setting the period of power application to the motor (11), a PWM position setting block (12) for setting the PWM position in power application to the motor, and a power application control block (9) for controlling power application to the motor. The power application control block (9) controls power application in accordance with the position of a magnetic pole of the rotor, so that the power application period is in a range not smaller than 120 degrees and smaller than 180 degrees. The first portion of one power application period includes a first section during which switching elements are PWM-controlled, a second section after the first section during which a predetermined switching element is kept on, and a third section after the second section during which the switching elements are PWM-controlled. |
