| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power conversion device capable of supplying an optimum flat voltage even at a low speed of a motor by solving the following problems: a conventional configuration, which cannot be controlled at a lower voltage than a voltage after the rectification of an AC voltage, cannot supply an optimum voltage during low-speed operation of the motor. <P>SOLUTION: The magnitude of a ripple voltage is estimated from capacitor capacitance, inverter output current, and output voltage, and step-down chopper control by PWM control synchronous with the estimation result is implemented to supply a lower voltage than a rectified one of an AC voltage and to generate a flat voltage. <P>COPYRIGHT: (C)2012,JPO&INPIT |
