REVIEWS - LETTERS - REPORTS ROBUST CONTROL METHODS A SYSTEMATIC SURVEY

The paper addresses the problem how to recognize a level of robust controller design and is aimed show the difficulties of implementation for practical use. In the first part of paper we introduce the survey of robust controller design for SISO systems with generalization design procedure for structured and unstructured uncertainties. The second part of paper is devoted to MIMO systems. In the frequency domain robust controller design procedure we reduce to independent design of SISO subsystems and in time domain the LMI or BMI approaches with polytopic system description are favorable. During the last decades, robustness has been recognized as a key issue in the analysis and design of control systems. The history of robust control design method based on small-gain-like robustness condition started by developing with the pioneering work of Zames. Only at the end of the 1980’s was a practical solution to this problem was found. It is worth to mention some algebraic approaches which followed the seminal works of [4] ;[2] and [1]. Theory of robust control system design belongs to those theories which work with a real plant described by a nominal model and model uncertainty. It is a model approval of real plant then there is no gap within the results obtained by control theory and real measurements. Therefore, robust control theory is very fruitful theory to study for practical purposes. In this paper, we focus our attention in two robust design problems. At first, a problem of robust stabilization of an uncertain system with structured uncertainty when plant is described by the transfer function with linear or multilinear interval for SISO systems and for MIMO systems the polytopic description of systems are considered. In the second, a problem of generalization of robust stabilization of an uncertain system with unstructured uncertainty for SISO and MIMO system is considered for robust decentralized controller design. The last part of paper is devoted to results of three laboratory practice. In this course described basic theory of robust controller design can be consulted also in [4]; [2]; [7]; [5]; [8]; [6]; [3].