LQG Self-Tuner Design for an Asymmetric Hydraulic System

Abstract

Due to the asymmetric features of this control system, the STR strategy with a fixed reference model is no longer valid. Thus, the LQG self-tuner incorporated with the simplified 1st-order ARMAX model is proposed. By minimizing the cost function, this proposed scheme not only provides a tuned optimal reference model, but also avoids concealing the additional zero and transient oscilation. In addition, an implicit integrator is deduced from the cost function to reduce steady-state error and the effect of disturbance. Thus, by verification of robustness measurement, it is proven that the LQG self-tuner is always superior to the classical STR and insensitive to various operating conditions.