H-INFINITY CONTROLLERS WITH A PID STRUCTURE

A review is given of the new H∞ Observations Weighted (HOW) optimal control law. The conditions under which the H∞ controller has a PID structure are identified and some implications for PID controller design are discussed. The simple form of this Hx control law makes it easy to analyse and design. Examples are presented of the design procedure which involves the specification of the cost-function weighting transfer functions. The controller may be applied in applications where fast computational procedures are important. © 1990 by ASME.