| 摘要 |
PURPOSE:To readily obtain desired braking force in a motor by firing only special element to supply DC current thereto when the generation of an AC motor is controlled. CONSTITUTION:When generated voltage signal set at a generating brake voltage setting potentiometer 60 is applied through a switch 61 closed upon request of braking to a voltage controlled amplifier 52, it is compared with the output voltage of a rectifier 21, and is erroneously amplified to become a current reference. This reference is compared with the output current of the rectifier 21 and is erroneously amplified by a current controlled amplifier 53 to obtain a phase control signal. This control signal determines the arcing angle of the gate of the thyristor to control the output voltage of the rectifier 21 to become proportional to the set position of the speed setting potentiometer 50. In this manner it can obtain desired braking force for dynamic braking of the motor. |
