Optimization of the Test Frequency of NPP Active Safety Systems in the Over-Design Operation Life

V. I. Skalozubov, V. Yu. Kochnyeva,
Alali Mohammad, Algerby Rabia K. Ali

Odessa National Polytechnic University,
1, Shevchenko ave, Odesa, 65044, Ukraine

DOI: doi.org/10.31717/2311-8253.21.3.2

Abstract

The need to optimize the test frequency of thermal mechanical equipment of active safety systems of nuclear power plants is determined by the fact that, on the one hand, an increase in the test frequency reduces the probability of “latent” defects, critical for reliability and operability, in the “standby” mode of performing safety functions, and on the other hand, the probability of failure because of equipment wear during testing increases. Based on operating experience and the actual technical condition of the equipment, a method for optimizing the test frequency of active safety systems during the over-design operation period is presented. The calculated substantiations clarified that the optimal test frequency is two times less than the design onewith the extension of the service life; and when the operation life is extended for 12 and 20 years, the optimal test frequency decreases by 65% and 95%, respectively.

Keywords: active safety system, optimization, test frequency, periodicity, operation life extension, nuclear power plant.

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