Control system improvements: Feed-forward, adaptive,fuzzy control

摘要

A proportional-integral-derivative (PID) controller has limits and can be improved and optimized. Expansion of other control architectures doesn't mean PID-based control systems are dying. Control systems are advancing with other technologies. Examples of control system advances follow. Feed-forward control itself is another name for an open loop control. Such a control is not precise and cannot cope with the system disturbances, so it is very rarely used. However, it can be combined effectively with feedback control. There are actually two options of the feed-forward combined with feedback control. They differ based on a variable, which is processed by the feedforward path. Figure 1 shows both possibilities of feed-forward control (compensation).