Modern control theory applied to boiler control

This paper deals with the design of a multivariable control system for a ship boiler. The control system is based on Linear/Quadratic Optimal Control theory but with some additional features included to cope with the practical problems which occur in connection with an installation on a real plant. A Kalman filter is included in order to estimate the process state vector. It is also demonstrated how the most characteristic parameters in the boiler model can be estimated by applying the Extended Kalman filter technique. Computer aided design packages (CAD) and a real-time simulation system have been utilized in the design of control strategies and investigations of the control system performance. The system was installed on board the 285000 tdw tanker T/T "SONGA" in 1974 and experiences from the system in operation prove that it has been a successful implementation of modern control theory.