A simple dynamic model of the primary circuit in VVER plants for controller design purposes

A simple low dimensional nonlinear dynamic model of the primary circuit in a VVER-type nuclear power plant is developed from first engineering principles that is able to capture the most important dynamics of the system in normal operating modes. The model includes the description of the main control loops in the system, too.The model has been verified and validated by using measured data from three VVER-440 units of Paks Nuclear Power Plant in Hungary, and a good fit has been obtained. This qualifies the model to be the basis for the integrated re-design of the primary control loops.