Results of reactor core symmetry measurements at Bohunice and Mochovce NPPs

Reactor core symmetry measurement is carried out as one of the reload start-up physics tests at the Bohunice and Mochovce NPPs. The paper deals with the symmetry measurement results obtained in the Bohunice and Mochovce NPPs since the Gd-2 fuel has been applied in core loads. At first, the symmetry measurement procedure and evaluation method is presented. Then, measurements results from reactor cores loaded with Gd-2 fuel at Bohunice Units 3 and 4 and Mochovce Units 1 and 2 are summarized. The results obtained from the Mochovce Unit 1, the ninth fuel cycle are analysed in detail, because these results did not met their acceptance criterion. The procedures applied in the case of the acceptance criterion non-fulfilment together with possible reasons of the acceptance criterion non-fulfilment are described in the paper. (Authors)