Multivariable High-Gain Control with Feedforward Compensation - A Design Technique

State space analysis of linear time-invariant multivariable systems has been the subject of many researches in the past 2-3 decades. Trying to find an analogy between single-input, single-output and multi-input multi-output systems, so that the successful classical methods can be applied to multivariable systems, is more recent. Each individual research contributes in part to find a better solution to the main, still not completely solved, problem of designing a good controller for this class of systems. In this paper, results of several works on multivariable systems are combined to give an easy to use design technique for robust high-gain controllers by output feedback, inner-loop feedback and feedforward. An illustrative example is included.