| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power conversion device wherein it is possible to reduce the capacitance of a capacitor located between a power converter and a switch means more than before, suppress fluctuation in the voltage of the capacitor, and reduce the size and weight of the power conversion device. <P>SOLUTION: The power conversion device includes: a first capacitor 5 connected in parallel with a direct-current power supply 6; the power converter 2 that drives a synchronous machine 1; a second capacitor 3 connected in parallel with the direct current side of the power converter 2; the switch means 4 placed in the first capacitor 5 and the second capacitor 3; and a controlling means 9 that controls the power converter 2 based on the respective pieces of detection information from a speed detecting means 7 for detecting the speed of the synchronous machine 1 and a second voltage detecting means 8 for detecting the voltage of the second capacitor 3. The controlling means 9 keeps the switch means 4 off when the power converter 2 is at a stop. When the operation of the power converter 2 is started, it turns on the switch means 4 and simultaneously starts the power converter 2 and thereby controls an exciting current so that the terminal voltage of the synchronous machine 1 becomes equal to a predetermined value. <P>COPYRIGHT: (C)2010,JPO&INPIT |
