Measurement of VVÉR Control Rod Efficiency

The reasons for the large discrepancies between the computed and experimentally measured values of the efficiency of control rods observed during startup experiments on a VVER reactor are discussed. The spatial distribution of the neutron flux has the greatest effect. A method for eliminating the influence of spatial effects on the measurements of control rod efficiency is proposed. The possibilities of the proposed method are illustrated for examples of the analysis of experiments performed on power-generating units with VVER-440 and -1000 reactors.