Magnetic particle clutches are useful actuator devices for high power requirements because they can typically provide a 200-W mechanical power output. The particle clutches provide a high torque-to-inertia ratio and fast time-constant response. A particle clutch positioning system for nuclear reactor rods is shown in Figure P10.4. The motor drives two counter-rotating clutch housings.
The clutch housings are geared through parallel gear trains, and the direction of the servo output is dependent on the clutch that is energized. The time constant of a 200-W clutch is T = 1/40 s. The constants are such that KTn/J - 1. We want the maximum overshoot for a step input to be in the range of 10% to 20%. Design a compensating network so that the system is adequately stabilized. The settling time (with a 2% criterion) of the system should be less than or equal to 2 seconds.
