| 摘要 |
<p>The purpose of the present invention is to inhibit excessive rises in the temperature of a smoothing capacitor. Accordingly, a carrier-wave advance angle adjustor (158) calculates, on the basis of measurement values (Iu^, Iv^, Iw^) of a winding current and target voltages (Vu*, Vv*, Vw*), advance-angle command values (Ta, Tb, Tc) for redeploying non-circulation periods of respective phases so as to be staggered with respect to each other, and outputs the advance-angle command values to a carrier-wave generator (157). The carrier-wave generator (157) generates pulse-width-modulation (PWM) carrier waves (Ca, Cb, Cc) on the basis of the advance-angle command values (Ta, Tb, Tc) inputted from the carrier-wave advance angle adjustor (158), and outputs said PWM carrier waves respectively to multipliers (154, 155, 156). PWM counters (151, 152, 153) generate gate signals (Gu, Gv, Gw) on the basis of the target voltages (Vu*, Vv*, Vw*), and the carrier waves (Ca, Cb, Cc) which have had the amplitudes thereof adjusted by the multipliers (154, 155, 156).</p> |
