Water-Level Control for the U-Tube Steam Generator of Nuclear Power Plants Based on Output Feedback Dissipation

U-tube steam generator (UTSG) is one of the most important facilities in a pressurized-water nuclear reactor. The water level control of UTSG is crucial to secure the sufficient cooling inventory for the nuclear reactor and, at the same time, to prevent the damage of turbine blades. Because of high nonlinearity and nonminimum phase characteristics of steam generator dynamics, it is necessary to establish an effective nonlinear water-level controller. After establishing the state-space model of a UTSG, an output feedback dissipation control (OFDC) for nonlinear systems is presented, and then an output feedback dissipative L ₂ disturbance attenuator is also proposed. The robustness of the OFDC is analysis through comparing the two controllers. Furthermore, the OFDC is applied to water-level control for the UTSG of a low temperature reactor (LTR). Numerical simulation results with comparison to a PID-like water-level controller show the high performance of the OFDC.