Dynamic Sliding Mode Control of Nuclear Steam Generators Using Out-Put Feedback Based on a Nonlinear Model

U-Tube Steam Generator (UTSG) is a crucial component in nuclear power plant with the pressurized-water reactor. Ineffective control of the Steam Generator (SG) water level in the secondary circuit of a nuclear power plant can lead to frequent reactor shutdowns or damage the turbine blades. The difficulties in designing an effective level controller for UTSG arise mainly from the following two factors: first, high nonlinearity and second, non-minimum phase characteristics due to the so-called “swell and shrink” effect. Therefore, designing a suitable controller is a necessary step to enhance the nuclear power plant availability factor. The purpose of this paper is to design, analyze and evaluate a water level controller for U-tube steam generators using dynamic sliding mode control based on a nonlinear model of them. The above mentioned method is easy to implement in practical applications. Moreover, the dynamic sliding mode control exhibits the desired dynamic properties during the entire output-tracking process, independent of disturbances and uncertainties. To validate the designed controller, a steam generator simulator is used with simulation of occurance of an accident in a real nuclear power plant. The simulation results show the performance, robustness, and stability of the proposed controller.