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This paper presents a general approach and techniques for design and verification of Field Programmable Gates Arrays (FPGA)based Instrumentation and Control (I&C) systems for Nuclear Power Plants (NPP). Appropriate regulatory documents used for I&C systems design, development, verification and validation (V&V) are discussed considering the latest international standards and guidelines. Typical development and V&V processes of FPGA electronic design for FPGA-based NPP I&C systems are presented. Some safety-related features of implementation process are discussed. Corresponding development artifacts, related to design and implementation activities are outlined. An approach to test-based verification of FPGA electronic design algorithms, used in FPGA-based reactor trip systems is proposed. The results of application of testbased techniques for assessment of FPGA electronic design algorithms for reactor trip system (RTS) produced by Research and Production Corporation (RPC) Radiy are presented. Some principles of invariantoriented verification for FPGA-based safety-critical systems are outlined.

This paper addresses the problems associated with dependability analysis of complex information and control systems (I&CS). FME(C)A-technique is proposed as a unified approach to I&CS dependability assessment. Classic philosophy is extended by introducing new items into assessed objects, relevant causes, assessed effects, assessed attributes and used means. FME(С)А-tables and models for dependability (reliability, survivability and safety) attributes assessment are constructed. Elements of information technology of I&CS analysis are presented.

To protect safety-critical systems from common-cause failures that can lead to potentially dangerous outcomes, special methods are applied, including multi-version technologies operating at different levels of diversity. A model representing different diversity types during the development of safety-critical systems is suggested. The model addresses diversity types that are the most expedient in providing required safety. The diversity of complex electronic components (FPGA, etc.), printed circuit boards, manufacturers, specification languages, design, and program languages, etc. are considered. The challenges addressed are related to factors of scale and dependencies among diversity types, since not all combinations of used diversity are feasible. Taking these dependencies into consideration, the model simplifies the choice of diversity options. This chapter presents a cost effective approach to selection of the most diverse NPP Reactor Trip System (RTS) under uncertainty. The selection of a pair of primary and secondary RTS is named a diversity strategy. All possible strategies are evaluated on an ordinal scale with linguistic values provided by experts. These values express the expert’s degree of confidence that evaluated variants of secondary RTS are different from primary. All diversity strategies are evaluated on a set of linguistic diversity criteria, which are included into a corresponding diversity attribute. The generic fuzzy diversity score is an aggregation of the linguistic values provided by the experts to obtain a collective assessment of the secondary RTS’s similarity (difference) with a primary one. This rational diversity strategy is found during the exploitation stage, taking into consideration the fuzzy diversity score and cost.