| 摘要 |
<P>PROBLEM TO BE SOLVED: To minimize excessive current flow due to pulsation of the output current from an inverter device for driving a three-phase induction motor when a transition is made from three-phase PWM control where three-phases are switched entirely to a two-phase PWM control where switching of one phase is brought to rest. <P>SOLUTION: In the inverter device which inverts a DC voltage to an AC voltage of an arbitrary frequency by PWM control, phase voltage waveforms calculated in a phase voltage waveform generation processing block 201 for three-phase PWM where the output phase voltage waveform of the inverter is calculated from an output frequency command and an output voltage command, a phase voltage waveform generation processing block 202 for two-phase PWM, and a voltage waveform transient processing block 203 for three-phase/two-phase transition are switched in a PWM output block 205 based on a signal from a switching determination processing block 204, and output to a PWM output generation block 207 thus generating a PWM wave. <P>COPYRIGHT: (C)2012,JPO&INPIT |
