| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a motor dive that has an inexpensive construction, accurately detects phase current, and can provide a high-quality drive from low-speed regions to high-speed regions. <P>SOLUTION: The motor drive is provided with an inverter 2, a current detecting section 11 that detects the inverter busbar current, an induced voltage estimating section 17 that estimates the motor induced voltage from the inverter output voltage value and the current value from the current detecting section, a rotor position speed detecting section 18 that estimates the rotor position of the motor based on the estimated value of the induced voltage, a pulse width modulation (PWM) signal generating section 9 that generates PWM signals to control the inverter based on information on the estimated rotor position, and a duty ratio correcting section 19 that corrects the duty ratio of the PWM signal generated in the PWM signal generating section. The duty ratio correcting section 19 corrects the duty ratio of the PWM signal generated in the PWM generating section to suck level as giving no change to the PWM signal during the period that the current detecting section detects the inverter busbar current. <P>COPYRIGHT: (C)2003,JPO |
