| 摘要 |
PROBLEM TO BE SOLVED: To provide a 3-level inverter device in which the fluctuations of a DC neutral voltage can be suppressed, while the amplitude of a modulation wave signal does not increase excessively. SOLUTION: A compensation voltage calculated by a compensation voltage calculating means 6 is added to 3-phase output voltage command values, to obtain modulation wave signals and gate signals by which switching devices S1U-S4W are turned on and turned off are outputted in accordance with the modulation wave signals. With this constitution, as the compensation voltage is very small, the amplitudes of the modulation wave signals obtained by adding the compensation voltage to the output voltage command values are not excessively large and, furthermore, the fluctuation of the neutral voltage can be reduced. |
