On Dynamic and Operational Stability of NPP Power Units with VVER-1200

3/18/2024 2024 - #01 Nuclear power plants

Gusev I.N. Smorodinov D.S. Kazakov K.V. Zhudenkov V.V. Mamontov G.A.

https://doi.org/10.26583/npe.2024.1.02

The operating experience of NPP power units with VVER-1200 provides evidence of a possible significant deviation of technological parameters of primary and secondary circuits in transient operating modes from normal operating conditions. Changes in the operating modes of equipment and automatic process control systems in transient operating modes of the mentioned power unit also proved to be possible. These events may lower the margins which trigger the main equipment shutdown. If additional equipment failures coincide with the initial event, it is possible that safety systems may be triggered unnecessarily, followed by a violation of operational limits, disconnection of the power unit from the network, and triggering of scram.

The article, as the first part of a publication on this topic, covers formulation issues of increasing the dynamic stability of NPP power units with VVER-1200, both within projected transient modes of normal operation, and a violation of normal operating conditions. The concept of dynamic and operational stability of NPP power units is introduced. The article also discussed the main approaches and provisions of the methodology for analyzing the dynamic and operational stability of a power unit. Preliminary technical proposals aimed at improving the dynamic and operational stability of power units No. 6 and No. 7 of the Novovoronezh NPP are considered in the article. These proposals are based on the examples of improving the process control algorithms of individual systems and elements of the primary and secondary circuits.

The results of computational analyzes with substantiation of specific proposals for modernizing process control algorithms for NPPs with VVER-1200 will be included in the second part of publications on this topic.

References

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dynamic stability operational stability VVER-1200 transients normal operation

Link for citing the article: Gusev I.N., Smorodinov D.S., Kazakov K.V., Zhudenkov V.V., Mamontov G.A. On Dynamic and Operational Stability of NPP Power Units with VVER-1200. Izvestiya vuzov. Yadernaya Energetika. 2024, no. 1, pp. 18-27; DOI: https://doi.org/10.26583/npe.2024.1.02 (in Russian).