| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a PWM pulse generating method for changing an output phase into three levels even in an AC-AC power conversion apparatus having a non-smoothed DC busbar. <P>SOLUTION: In the AC-AC power conversion apparatus where a polyphase AC power supply is directly converted into AC output of arbitrary amplitude and frequency by opening/closing of a plurality of switches 4a to 4f and 5a to 5f, and current can be made to flow in both directions, means 6 to 11 adjusting opening/closing timing of the switches 4a to 4f and 5a to 5f so that potential of the output phase changes stepwise for three levels or above and an input phase connected to the output phase becomes two or below are arranged. <P>COPYRIGHT: (C)2008,JPO&INPIT |
