On switching H∞ controllers for nuclear steam generator water level: A multiple parameter-dependent Lyapunov functions approach

Poor control of the steam generator (SG) water level in the secondary circuit of a nuclear power plant can lead to frequent reactor shutdowns. From the viewpoint of economic operation, it is critical to keep the water level of SG in well control. This paper presents a new framework for addressing this problem based on switching control to linear parameter varying (LPV) systems. A family of LPV controllers are designed, and each of them is suitable for a specific operating range. Under the admissible switching logic, the closed-loop system remains stable and achieves prescribed H∞ performance in the entire operating range. The approach is based on multiple parameter-dependent Lyapunov functions, which is less conservative than the employment of a single Lyapunov function. The switching LPV control scheme is then applied to the level control problem.