| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to adjust the output voltage with the DC voltage unchanged even in a region of a high output frequency by setting pulse modes of a plurality of PWM inverters for each arbitrary inverter. SOLUTION: A multiple inverter is constituted of a plurality of PWM inverters 1, 2, 3 which receive DC voltage and output AC voltage and a synthesizing transformer 18 which receives the outputs of the PWM inverters 1, 2, 3 and outputs synthetic voltage. In this multiple inverter, pulse modes of the PWM inverters 1, 2, 3 are set for each arbitrary inverter. By this method, a range of voltage the multiple inverter cannot output at high frequencies can be made small without changing DC voltage. Therefore, in the multiple inverter of a large capacity, the voltage which cannot have been output due to the restrictions of such an element as GTO can be now obtained. |
