Spatial control of a large PHWR via reduced model

The paper presents the design of state feedback control for a large pressurized heavy water reactor (PHWR) by developing a reduced-order model for the same. The nonlinear mathematical model of the PHWR is linearized around an operating point corresponding to fullpower operation of the reactor. The linear model has 14 inputs and outputs each and 56 states. Application of the reduction technique leads to a simplified model characterized by only 14 states. This 14th-order simplified model is used to design a linear quadratic regulator, and state feedback gains for the original 56th-order system are obtained without any significant difficulty. The transient performance of the closed-loop system is tested by simulation of the original nonlinear model of the PHWR