| 摘要 |
PURPOSE:To ensure a stable synchronous operation of a hysteresis motor by regulating the power source voltage according to a difference between a power factor and a reference power factor thereof. CONSTITUTION:A DC current obtained from an AC power source 1 through a rectifier 2 and filters 3 and 4 is applied to a hysteresis motor 6 after converted to an AC current with an inverter circuit 5. The output (p) of a power factor detection circuit 12 of the motor 6 is compared with the output PR of a reference setting device 13. The resultant difference is inputted into an amplifier 14 as an error signal. When the output of the amplifier 14 is zero, namely, P=PR, it is retained with an integration circuit 15. Based on a set value VR of a rated voltage from a reference voltage setting device 11, a feed back VM of an inverter output voltage and a power factor error signal VP, a signal VR+VP-VM is provided to a control circuit 10 to regulate a DC output voltage of the rectifier 2. |
