Robust and adaptive control of a multi-variable system

An on-line robust control and robust adaptive control of a multi-variable system has been developed to solve the problem of plant/model mismatch. An on-line stability index is proposed for stability indication of the control system. Although very small mismatch can be handled by conventional feedback control, moderate and large mismatch must be corrected by on-line robust and robust adaptive control, respectively. Regarding the former, the control algorithm is based on tuning the parameters of designed filters, and the tuning method depends on the robust stability index which is on-line determined. Regarding robust adaptive control, system identification is carried out, and the identified model replaces the original one. Control of a continuous stirred tank reactor (CSTR) is presented to illustrate the proposed method.