Order reduction of a complete PWR-plant model and optimal design of an overall plant observer

A computer code capable of reliably predicting an optimal control strategy for a complete pressurized water reactor nuclear power plant is developed. The state, control, disturbance, and output vectors for the reactor, steam generator, pressurizer, reactor coolant pump, and turbogenerator unit are defined. The overall system is found to be of order 38, and calculational management requires an order reduction. This is accomplished using the Litz method of dominance measures. Order reduction based solely on the location of the eigenvalues in the s plane is also investigated. For the same reduced-order model, the Litz method dominance hierarchy of the plant states seems to make better sense, and unlike the conventional eigenvalue approach it gives accurate results when compared to original system responses. Finally, an overall plant observer is designed based on a seventeenth reduced-order system model. It is based on greatly reduced calculations, thus requiring less hardware, and is a more reliable predictor.