| 摘要 |
PROBLEM TO BE SOLVED: To expand an overmodulation rate while suppressing harmonic components when a PWM voltage is generated in an inverter.SOLUTION: An overmodulation rate calculation part is provided for calculating an overmodulation rate by dividing a voltage command amplitude by Vdc/√2. The proportion between two voltage vector time ratios used for outputting a voltage command is changed depending on the calculated overmodulation rate to expand the overmodulation rate. For this expansion, setting of the proportion between the two voltage vector time ratios is performed while referring to a parameter that is set so as to correspond to the overmodulation rate preliminarily stored in a table. |
