| 摘要 |
<P>PROBLEM TO BE SOLVED: To perform the switching from usual action to protective action safely and perform the recover from protective action to usual action safely and smoothly, without needing complicated control algorithm, in a multilevel PWM inverter controller. <P>SOLUTION: In case that a measured current value I is over a first reference value I<SB>1</SB>and smaller than a second reference value 2, a zero vector which begins from a certain state where middle potential is outputted as to all phases(step 22). In case that the current value I is over the second reference value I<SB>2</SB>and smaller than a third reference value I3, base block action which turns off all switching elements after output of a zero vector is performed (step 28). In case that the reference value I is over the third reference value I<SB>3</SB>, emergency stop is performed (step 29). When recovering to usual action after performing the base block action, the recovery to the usual action after performing the output action of the zero vector is performed. <P>COPYRIGHT: (C)2004,JPO |
