| 摘要 |
PURPOSE:To reduce the unbalance rates between the respective phase of the output voltage of the titled device by a method wherein connection of the terminal of the auxiliary winding of the phase converter to the middle terminal of the plural number of the output winding of a transformer to supply electric power to the phase converter thereof is changed selectively corresponding to load capacity of the phase converter. CONSTITUTION:The middle terminals Z1, Z2 having the different output voltages mutually are provided to the output winding 21 of the transformer 10, and the middle terminals Z1, Z2 thereof and the terminal Z of the auxiliary winding 16b of the phase converter 16 are connected selectively accroding to the switch 22a or the switch 22b of a selective switch 22 to close a circuit. When the value of a current to flow in the W phase is increased or reduced to the previously selected value to enable to reduce the unbalance rate of the output voltage of the phase converter 16 at the whole region of load capacity, the switch 22b or 22a of the selective switch 22 is made to the conducting condition. |
