Adaptive controller design for a nonlinear drum-boiler turbine system

This paper analyzes the feasibility of designing nonlinear controllers to regulate the drum pressure and reheater pressure of a drum-boiler turbine system. In the case when all the parameters are precisely known, an exponential stabilizer is constructed using a Lyapunov-based design. In the case when some of the parameters are unknown, we first design a parameter estimator whose estimates are guaranteed to converge to the real values in a finite time. With the help of the estimates, we construct two controller dynamics which regulate the pressures of the drum and heaters to their respective desired values. The controllers are also evaluated through computer-based simulation, which illustrate that the adaptive controllers can achieve good performance while maintaining the controller values within the operational limit.