The design of a direct current generator field controller

A controller was built utilizing transistors and silicon controlled rectifiers to allow torque control of the General Electric dynamometer, type TLC-50. The current gain of the controller was approximately 10⁶ such that the field current could be controlled by an input current of zero to approximately two microaaperes. The transfer function for the controller-dynamometer system was experimentally determined. The results indicate that the gain of the open loop torque control system is constant for frequencies up to 1.1 radians per second. Satisfactory values of gain for proportional and proportional plus integral control, were experimentally determined by operating the closed loop systems at different gain values, and looking at the response of the system to a step input. The desired response was to reach the new set point as fast as possible with a minimum amount of overshoot. The time required for the system to reach the steady-state operating point was approximately 0.5 seconds with no detectable overshoot --Abstract, page ii