Decentralized multivariable PID controller with pre compensator for gas turbine system

In this paper, a restricted structure of PID controller is proposed for automobile gas turbine by considering a LQG cost function. So PID Controller coefficients are calculated by minimizing this cost function. One of the most important characteristics of this approach, its ability to design various structure PID controllers by solving optimization problem only for one time, moreover it can approximate main optimization problem by a repetitive Quadratic optimization Problem (QP). This approach is convex optimization and has an analytic solution; therefore its calculations are not complicated. In defined cost function, there are two weighting functions, control error and control action; they are adjusted to meet economical (control action) and operational (control error) requirement. Moreover, using restricted structure control criterions prepare appropriate conditions for designer. Restricted structure controller based on LQG, has proper low frequency gain and limited output variance. At first, appropriate input and output for gas turbine system is chosen and pre compensator is designed for decoupling of loops. After that mentioned controller is designed and applied. Simulation results indicate desired performance of gas turbine closed loop system with designed controller.