| 摘要 |
PROBLEM TO BE SOLVED: To suppress the fluctuation in a DC voltage by preparing an AC side voltage command value, by adding an AC power supply voltage detection value to a line voltage command value which keeps the voltage of a DC capacitor to the command value. SOLUTION: An AC current regulator 11 prepares a line voltage command value Vtr* to be applied to an exciting transformer 2 based on the deviation between the AC side current detected value Ic from an AC current detector 7 and an AC side current command value Ic* from a DC voltage regulator 8. Because the AC side voltage command value Vc* is prepared by adding the AC power supply voltage detected value Vs to the above, the voltage Vc responds instantly to a sudden change in voltage Vs→Vs' and quickly changes to a voltage Vc', and the voltage Vtr hardly changes. Therefore, a current Ic' hardly changes from the initial current Ic. This means that there is almost no fluctuation in energy which passes the power converter 3 before and after the fluctuation in voltage Vs. As a result, the DC voltage Ed as its output is kept constant. Thus, the inverter 5 is able to perform a stable operation with a high accuracy continuously.
|
