DECENTRALIZED PID CONTROLLER DESIGN FOR UNCERTAIN LINEAR SYSTEM

A state space approach to designing decentralized (multi-loop) PID robust controllers is studied for linear time varying uncertain system with affine (polytopic) uncertainty. The bounded parameter variation rate is assumed. Both continuous PID and discrete time PSD controller design is discussed for constrained structure of controller matrix. The Lyapunov stability approach with parameter dependent Lyapunov function is considered to decrease conservativeness of quadratic stability approach. For parameter varying systems with the bounded parameter variations, the parameter variation upper bound is included in stability conditions and control design procedure.