Robust Controller Design for Boiler System

In this paper, a robust controller is designed for boiler system based on loop-shaping H_infin control. Loop shaping method is to choose compensator to shape open-loop singular frequency property, so get close-loop performance, and trade off between robust performance and robust stability. its essentiality is to shape systempsilas frequency property. The method by regulating systempsilas frequency property to get desired performance is familiar with technician. Because state space has property of numeration convenient, so transform shaped model to state space for numeration to get accuracy solution. The procedure gives how to choose pre-compensator determined the performance of the final closed-loop system for Loop shaping method. In order to implement the complex H_infin controller, a method is proposed to reduce high controller which get from Loop shaping H_infin method to a multivariable PID controller. Simulation shows that the designed multivariable PID controller have good robust stability and performance.