Research on fuzzy-PID switch controller applied to pressure control of once-through steam generator

Once-through steam generator in concentric annuli tube is a new type steam generator which adopts structure of double-face heat transfer. The model of steam generator is built by lumped parameters with moving boundary. In the basis of the built model, static and dynamic characteristics are analyzed. Because thermal capacity is relatively less, it enhances difficulty of control. On the basis of trails of PID controller and fuzzy controller, fuzzy-PID switch controller is applied to regulate tightly pressure of exit steam, using feed water flow as controlled variable in this paper. A mathematic model of once-through steam generator in concentric annuli tube is derived. The application of designed fuzzy-PID switch controller to once-through steam generator in concentric annuli tube pressure control of exit steam is discussed and simulation results show that this algorithm possesses better dynamic performance and robustness than conventional PID strategy.