| 摘要 |
PURPOSE:To simplify a constitution of the whole system and lower its price by enabling an induction motor to be driven at a variable speed through a separately excited inverter. CONSTITUTION:When an induction motor 9 is started, a switch 15 is closed and AC power is supplied from an AC power supply 1 directly to said induction motor 9 and to a capacitor 13 connected in parallel therewith to start said motor 9. After that, a separately excited power converter is first placed in a load-commutable state, and then a switch 14 is closed and the switch 15 is opened to switch said power converter to a separately excited inverter 11. In this manner, the separately excited inverter 11 is made load-commutable and operates as a separately excited apparatus to drive the induction motor 9 at a variable speed. |
