| 摘要 |
PURPOSE:To enable to avoid unnecessary current limit of an inverter device by seting the limiting level of the output current of a self-excited inverter to variable value by linking the level to the voltage of a DC intermediate circuit, thereby sufficiently utilizing the commutation capacity at every time. CONSTITUTION:The detected output of an output voltage detector 6 of a self- excited SCR inverter 2 is compared with the set value of a voltage setter 7, and the deviation is applied to a voltage regulator 4. On the other hand, a current detector 8 converts an AC current obtained from a current transformer 10 into a DC current, the detected output is compared with the output of a variable current reference setter 9 connected to a DC intermediate circuit between a DC power source 1 and the inverter 2, and the deviation is applied to a current regulator 5. Since the setter 9 is connected to the DC intermediate circuit, the limiting value of the output current is reduced to a small value when the DC voltage is reduced. In this manner, unnecessary current limit can be avoided by sufficiently utilizing the commutation capacity at every time. |
