NuEditor

Abstract

The digital software control system in nuclear power plants is a safety-critical system where reliable techniques must be applied to it in order to preserve safety in the whole system. Formal specification and verification technique are known to improve the safety of safety-critical system software. Formal specification techniques especially allow the system to be clearly and completely specified in the early requirements specification phase. Formal verification methods can detect errors which can not be detected using the methods such as inspection, and safety analysis techniques. Since formal specification and verification methods can preserve safety in the whole system, recently there has been a great increase of researches and applications in the industrial field. In this paper, we present NuEditor, an integrated specification and verification environment to perform both specification and verification of requirements specification written in NuSCR. NuEditor offer convenience of specification to specifier through check of syntactic error. Moreover, it can provide information about omitted or conflicted requirements, since NuEditor provide a functionality to preserve the completeness and consistency of the NuSCR specification. More complex system properties can be verified automatically using formal verification techniques by NuEditor. To implement automatic verification environment, we also propose translation rules for NuSCR into SMV. To demonstrate the usefulness of our proposed NuEditor, we present a trip logic of BP(Bistable Processor) in DPPS(Digital Plant Protections System) RPS(Reactor Protection System) in nuclear power plant as an example system, which is currently being developed in Korea. When we specify a trip logic of BP, frequently occurring errors such as omission of input/output variable and logic are effectively identified. Verification using model checking and theorem proving is proven to be applicable and effective to chec...