| 摘要 |
PROBLEM TO BE SOLVED: To provide a controller for a single-phase induction motor that safely performs the switching operation from an operation based on a commercial power source to an operation based on an inverter without temporarily stopping a motor.SOLUTION: A controller for a single-phase induction motor has an inverter 5 for applying to a primary winding 7 and an auxiliary winding 8 an AC voltage having a frequency which is not more than a commercial power source frequency, first opening/closing parts (SW1a, SW1b) connected so as to form a closed circuit together with a commercial power source 1 and the primary winding 7, and a second opening/closing part (SW2) connected to the commercial power source 1 and the auxiliary winding 8 in series so as to form a closed circuit together with the commercial power source 1 and the auxiliary winding 8. When a first driving mode in which the opening/closing parts are set to ON-state, the inverter 5 is set to OFF-state, and a single-phase induction motor 9 is driven by the commercial power source 1 is switched to a second driving mode in which the opening/closing parts are set to ON and the single-phase induction motor 9 is driven by the inverter 5, the inverter 5 is kept to OFF-state while the contact points of the opening/closing parts are set to ON-state. |
