Adaptive Backstepping PID Control for Boiler-turbine Units

Based on adaptive backstepping PID method, a control scheme for boiler-turbine units is presented in this paper. Firstly, a typical nonlinear model of the boiler-turbine units is considered. A coordinate transformation is introduced to move the equilibrium points to the coordinate origin. Then, the model is divided into two subsystems. Next, the backstepping control laws for the coordinated control system are proposed and the adaptive update rates of uncertain parameters are deduced. Finally, based on the Laplace transform, the PID form of the controllers is provided. By constructing the Lyapunov functions, the global regulation of the system is realized. The control method proposed in this paper can overcome the impact of typical nonlinear characteristics on the operating conditions, and effectively improve the adaptability of the system under large-scale variable operating conditions.