2-DEGREE-OF-FREEDOM CONTROLLERS FOR MULTIVARIABLE MODEL-MATCHING SYSTEMS - APPLICATION TO A CONTINUOUS STIRRED-TANK REACTOR (CSTR)

In this paper we study a robust control problem by the approach of mod el-matching design with a two-degree-of-freedom controller. First we g ive a parametrization of all stabilizing compensators from the viewpoi nt of independent design of feedforward and feedback controllers. Seco nd, utilizing the modern Wiener-Hopf method, we solve the optimal robu st control problem. The proposed controller can directly deal with the intrinsic problem of process interaction, plant uncertainty and contr oller saturation irrespective of whether the plant is stable or unstab le. The design method is applied to a continuous stirred tank reactor (CSTR) system. Computer simulation shows results with satisfactory per formance.