Abstract
In accordance with a complex program to improve the safety of Ukrainian NPP units, a number of “Post-Fukushima” upgrades are being implemented. The upgrades were identified based on the results of “stress-tests” performed after the severe accident at the NPP Fukushima Daiichi (Japan) and aimed at preventing or managing a severe accident. As part of the implementation of upgrades for the possibility of installation and commissioning of new equipment, in accordance with regulatory documentation, is required confirmation that the upgrade will not lead to a degradation of the NPPs safety. For this purpose, the safety analysis report and analytical calculations, including thermal-hydraulic, probabilistic and radiation analysis, are developed. In this paper, on the example of “Post-Fukushima” upgrades, the practical experience of performing analytical calculations in order to justify the safety of Ukrainian NPP power units is described. As an example, Zaporizhzhya NPP Unit 1 (reactor facility type: VVER-1000/V320, reactor type: PWR VVER-1000, operational electric power: 1000 MW) was chosen, which is a pilot for the implementation of “Post-Fukushima” upgrades in Ukraine mainly. In this paper, on the example of “Post-Fukushima” upgrades, the practical experience of performing analytical calculations in order to justify the safety of pilot unit is described.
Company ES Group and its employees took part in the implementation of most upgrades by supporting domestic and foreign companies, as well as the NPP operator, for the successful implementation of upgrades using the best technical solutions and modern calculation justifications.
