| 摘要 |
<P>PROBLEM TO BE SOLVED: To positively suppress a surge voltage and prevent voltage accuracy and voltage disturbance due to minimum pulse width limitation without complicating a minimum pulse width limitation circuit. <P>SOLUTION: A PWM operator 105 compares a voltage command with a triangle wave carrier signal to generate a PWM command of a PWM waveform. If the pulse width of the PWM command is smaller than a set value of a minimum pulse width, a minimum pulse width limitation circuit 106 extends the pulse width and limits the minimum pulse width of PWM output of an inverter main circuit 101, thereby suppressing the generation of a surge voltage due to cable connection with a motor 102. The processing includes substantially equalizing an effective value of the PWM output voltage with a command voltage by correcting by the difference of the pulse width, and correcting the voltage disturbance due to the extension the pulse width by feedbacking the difference of the pulse width to the voltage command of the inverter to correct a voltage command of another phase. <P>COPYRIGHT: (C)2008,JPO&INPIT |
