RADIOELECTRONIC AND COMPUTER SYSTEMS

Ensuring the safe operation of nuclear power plants remains one of the most important tasks. An important role in ensuring the safety of nuclear power plants is played by instrumentation and control systems (ICS). Extremely high demands are made on such systems, first of all, on their reliability and functional safety. The object of research and analysis in this work is the Nuclear Island I&C Instrumentation System and Reactor Protection System, which are developed based on programmable RadICS Platform with self-diagnostic. The failure trees of such platforms and ICS based on them were developed. In the next stage, several Markov models of redundant ICS are developed. The article aims to develop and analyze the results of research on Markov models for reliability and safety assessment of ICS based on self-checking programmable platforms. The models take into account errors of checking and diagnostic tools, namely errors associated with identifying failures and failures of the corresponding components of the hardware and software/FPGA and channels of redundant structures. Models have been developed for various options of redundant structures and taking into account the diversity principle for ISC structure and failure rate caused by design defects. Multiple-fragment Markov Models of ICS were also investigated. The scientific novelty lies in the fact that the proposed models take into account an expanded set of parameters of self-diagnosing programmable platforms, ICS, the processes of their use and maintenance. Recommendations on the selection of parameters and structural ICS are formulated.

Information and Control System; Reactor Protection System; Fault Tree; Functional Safety; Availability Function; Multiple-fragment Markov Model

IEC 61513. Nuclear power plants – instrumentation and control for systems important for safety – general requirements for systems. International Electrotechnical Commission, 2011. 86 p.

IEC 61508, Electric / Electronic / Programmable Electronic safety-related systems, parts 1-7. International Electrotechnical Commission, 2010. 594 p.

Medoff, M., Faller, R. Functional Safety - An IEC 61508 SIL 3 Compliant Development Process. Exida, 2010. 282 p.

Kharchenko, B. C., Odarushchenko, O. N., Odarushchenko, E. B. Bazovie mnohofrahmentnie makromodely otsenky nadezhnosty otkazoustoychyvikh komp'yuternыkh system ynformatsyonno-upravlyayushchykh kompleksov [The Basic Multiple-fragment Markov Model reliability assesment of fault-tolerant computer systems for instrumentation and control systems]. Radioelektronni i komp'uterni sistemi - Radioelectronic and computer systems, 2006, no. 5(17), pp. 62-70.

Sklyar, V. V., Odarushchenko, O. N., Ponochovnyy, Yu. L., Bulba, E. N., Ivasjuk, A. O. Modely otkazov ynformatsyonno-upravlyayushchykh system na osnove samodyahnostyruemikh prohrammyruemikh platform v systemakh avaryynoy zashchyti reaktorov [Failure modes of information-control systems based self-checking soft platforms protection systems]. Radioelektronni i komp'uterni sistemi - Radioelectronic and computer systems, 2015, no. 4(74), pp. 19-24.

Trivedi, K. S., Kim, D. S., Roy, A., Medhi, D. Dependability and security models. Design of Reliable Commu-nication Networks, 2009. DRCN 2009. 7th International WS, Washington, DC, 2009, pp. 11-20.

Junior, R. M., Guimaraes, A. P., Camboim, K. M. A., Maciel, P. R. M., Trivedi, K. S. Sensitivity analysis of availability of redundancy in computer networks. In Proc. of the 4th International Conference on Communication Theory, Reliability, and Quality of Service, 2011, pp. 115-121.

Solve stiff differential equations and DAEs – variableorder method – MATLAB ode15s. Available at: https://www.mathworks.com/help/matlab/ref/ode15s.html (accessed: 01.10.2019).

Zheng Z. Markov Regenerative Models of WebServers for Their User-Perceived Availability and Bottlenecks. IEEE Transactions on Dependable and Secure Computing, 2017, pp. 1-1. DOI: 10.1109/TDSC.2017.2753803.

Hashemian, H. M. Predictive maintenance in nuclear power plants through online monitoring. Nuclear and Radiation Safety Journal, 2013, no. 4, pp. 42-50.

Kharchenko, V., Odarushchenko, O., Popov, P., Odarushchenko, V. Availability assessment of Computer Systems Described by Stiff Markov Chains: Case Study.CCIS, vol. 412, Springer, 2013, pp. 112-135.

Yastrebenetsky, M. A., Rozen, Yu. V., Vynohradskaya, S. V., Johnson, G., Eliseev, V. V., Siora, A. A., Sklyar, V. V., Spektor, L. Y., Kharchenko, V. S. Bezopasnost' atomnykh stantsii: sistemy upravleniya i zashchity yadernykh reaktorov [Safety of nuclear power plants: control and protection systems for nuclear reactors]. Kiev, Osnova-Print Publ., 2011. 768 p.

Yastrebenetsky, M. A., Vasylchenko, V. N., Vynohradskaya, S. V., Goldrin, V. M., Rozen, Yu. V., Spektor, L. Y., Kharchenko, V. S. Bezopasnost' atomnykh stantsii: Informatsionnye i upravlyayushchie sistemy [Safety of nuclear power plants: Information and control systems]. Kiev, Tekhnika Publ., 2004. 472 p.