| 摘要 |
<P>PROBLEM TO BE SOLVED: To augment output of an inverter by improving utilization factor of DC voltage input in the inverter by a simple means. <P>SOLUTION: In the inverter controller, a phase-voltage distribution control system and a modulation bias control system are combinedly utilized. In the phase-voltage distribution control system, the output command maximum value MB (equivalent to the maximum utilization factor obtained by the modulation bias control system) to be a first threshold is set in advance with respect to three-phase voltage command values Vu, Vv, Vw computed in the control part. Voltage amount exceeding the output command maximum value is distributed to the other two phases. In the modulation bias control system, while the voltage command value after distribution by the phase-voltage distribution control system exceeds the maximum modulation M (a second threshold), an arm on one side of a full-bridge inverter arm is made in a completely conductive condition, wherein the modulation is set to be 1. In the modulation of the arm on the other side, only the difference between the voltage of the modulation of 1 and the voltage command value is biased, thereby increasing the total modulation of both arms. <P>COPYRIGHT: (C)2004,JPO |
