V. I. Skalozubov, O. M. Vierinov, A. V. Kanivets, V. Yu. Kochnieva, D. S. Bundiev, H. Hayo
Interagency Center for Fundamental Scientific Research in Energy and Ecology Sector, 1, Shevchenko Ave, Odessa, 65044
DOI: doi.org/10.31717/2311-8253.23.3.2
Abstract
A reasonable reduction in the time of scheduled preventive maintenance of nuclear power units is a current direction for increasing the operational efficiency of the nuclear power industry in Ukraine. The main indicator of the operating efficiency of nuclear power plants (capacity factor) actually directly depends on the time of scheduled preventive maintenance of nuclear power units. One of the most effective approaches to reducing the time of scheduled preventive maintenance of power units is related to optimizing strategies of scheduled repair according to the technical condition of safety related systems. The introduction into operational practice of the concept of repair according to the technical condition of systems and equipment of nuclear power units determines the need to develop methods for substantiating strategies for optimizing the organization of scheduled repairs of the safety related systems of nuclear power plants, that take into account the impact of modernization of strategies for scheduled repairs of safety related systems on the safe operation conditions. A risk-informed method for optimizing safety related systems of nuclear power plants has been developed, which takes into account the impact of modernization of strategies of repairs according to technical condition on probabilistic safety factors. The developed risk-informed method defines permissible strategies of repairs according to technical condition of safety related systems in the three-parameter format “compliance of the determining parameters of the technical condition with the established criteria, Fussel-Veseli safety importance factor, Birnbaum safety importance factor”. Based on the
developed method, a simplified example of optimizing strategies of repairs according to technical condition for the fittings of safety related systems of the 1st power unit of the South Ukrainian NPP is given, and the conditions of admissibility of modernization of the regulations of scheduled repairs are determined. The operating organization National Nuclear Energy Generating Company “Energoatom” can use the developed risk-informed method to reasonably reduce the time of scheduled preventive maintenance of power units and increase the capacity factor of Ukrainian nuclear power plants
Keywords: repair, technical condition, safety system, nuclear power plant.
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