Outcomes of lifetime re-extension of the Novovoronezh NPP unit 4

Outcomes of lifetime re-extension of the Novovoronezh NPP unit 4.

Asmolov V. G., Povarov V. P., Vitkovskiy S. L., Meremyanin A. Y., Tarasenko I. A.

Lifetime re-extension for the Novovoronezh NPP unit 4 beyond 45 years is described. Works within the modernization period made it possible to broaden the range of design-basis accidents from the primary coolant leak from the DN100 mm hole to the accident associated with the main circulation pipeline rupture DN500 mm and ensured the compliance of the power unit 4 with the modern safety requirements in the nuclear power industry.
In addition, a unique experience was gained in using safety systems of the power of the Novovoronezh NPP unit 3 that was finally shutdown in 2016 for additional back-up of the safety systems and improving reliability of the power unit 4. The executed set of works demonstrated the correctness of the adopted concept of lifetime re-extension of the power unit 4, including, in terms of impact on safety, according to the Level 1 probabilistic safety analysis model for internal initiating events.

► Keywords: NPP, lifetime, security systems, evaluation of the modernization.

Article language: Russian. Pp. 5–24. [in Russian]. 10.26277/ SECNRS.2023.110.4.001.