Spatial control of advanced heavy water reactor by fast output sampling technique

In this paper, a spatial control strategy based on Fast Output Sampling (FOS) technique is proposed for Advanced Heavy Water Reactor (AHWR). The non-linear model of AHWR, represented by 90 first order differential equations having 5 inputs and 18 outputs, is linearized to obtain standard state-space representation. Using similarity transformation, the original higher order, ill-conditioned discrete system of AHWR is first decomposed into two comparatively lower order subsystems, namely, `slow' and `fast' subsystem of orders 73 and 17 respectively. Now, state feedback controls are designed separately for slow and fast subsystem and then a composite controller is obtained using these individual state feedback controls, which is then realized using FOS feedback gain. Thus, the states of the system are not required for feedback. The efficacy of the controller has been demonstrated by simulation of transient behavior of non-linear model of AHWR. Performance of the controller is found to be satisfactory.