PURPOSE: To accurately compensate the distortion of the output voltage of a current control type PWM inverter caused by dead time through simple arithmetic operation. ;CONSTITUTION: Three-phase voltage commands in U-, V-, and W-phases are calculated from current command signals and output current signals. At the time of generating a compensating voltage for compensating the distortion caused by dead time against the voltage command, the phase compensating value θ' corresponding to dead control time is calculated in step 600 and, after the polarity, positive or negative, of a phase-compensated current command is discriminated in step 602, a distorted voltage vf is used as a compensating voltage Δvu when the discriminated polarity is positive in step 603. When the discriminated voltage is negative, another distorted voltage-vf is used as the compensating voltage Δvu in step 604. In steps 605 to 607, a V-phase compensating voltage Δvv is found in the same way as that used for U-phase and, in steps 608 to 610, a W-phase compensating voltage Δvw is found and outputted. Therefore, the compensating voltages can be easily found and the distortion of the output voltage of a current control type PWM inverter can be compensated accurately.;COPYRIGHT: (C)1996,JPO
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