Stable robustness analysis for temperature control system of state feedback merging PID regulators

The stabilization is the target of a control system designing and the chief condition to improve control performance. The system stability proving is an important work of control theory research. And it has guidance meaning to control system design and application. This paper aim at control strategy of state feedback based on incremental function observer(IFO-KDeltax) merging with conventional PID controller, to investigate stable robustness of several different control systems formed of the strategy, and its stable conditions with corresponding theoretical proof are given for the control systems by mathematical analysis. Parameters adjustment and system commissioning methods for the different control scheme are also proposed. The results of theory research and engineering application show that IFO-KDeltax has strong stable robustness. When PID control is merged with state feedback, it plays a different role. The main function of PID regulator here is compensation for control error which generated by deviation between IFO-KDeltax and controlled object. And it provides with steady operation points for the control systems.