whose task is to adjust the position (distance or angle of rotation) of an element (e.g. valve control spool, slide) to match a setpoint as closely as possible. The negative feedback for the controlled variable can take the form of mechanical or electrical position feedback (Figure L 4).
Depending on the dynamic characteristics of the controlled subsystem and the demands made in terms of the pilot control behaviour and perturbation response of the closed circuit position control system, single loop control circuits or multi-loop feedback control circuits will be used.
Figure L 4: Closed circuit position control system