Locally optimal solution of robust ex-core detector response using constrained simulated annealing

This note describes the determination of the parameter vector used to estimate the axially 3-level average core power with ex-core detectors. The theoretical result of the previous work is performed by the well-known constrained quadratic programming method with active set method. Sometimes the previous method gives the solutions on the constraint boundaries not far from the inequality constraints although the solutions are feasible and acceptable. In this note, a constrained simulated annealing method is proposed to find the locally optimal but robust solutions. The method is applied to plant measurement data and its performance is demonstrated by core follow calculation for a core depletion cycle. The test results show the improvement in finding solutions not stuck on constraint boundary and its robustness by reconstruction accuracy for saddle type power distributions using the noisy measurement data.