정형 소프트웨어 요구사항으로부터 PLC 디자인의 체계적 생성

Systematic Generation of PLC-based Design from Formal Software Requirements

  • 유준범 (한국과학기술원 전자전산학과) ;
  • 차성덕 (한국과학기술원 전자전산학과) ;
  • 김창회 (한국원자력연구소 I&C-HMI) ;
  • 송덕용 ((주)엑트 엔지니어링 사업팀)
  • 발행 : 2005.02.01

초록

원자력 발전소의 디지털 제어 시스템은 안전성이 중요시되는 safety-critical 소프트웨어로서 충분한 수준의 안전성을 보장하기 위해서 여러 기법들이 적용되고 있다. 특히, 정형명세 기법은 개발의 초기 단계에서 소프트웨어 요구 사항들을 명확하고 완전하게 명세하도록 유도함으로써 안전성을 크게 향상시킬 수 있는 기법으로 인정받고 있다. 본 논문에서는 정형명세 기법인 NuSCR을 이용해서 작성된 요구사항 명세로부터, 설계 단계의 내용으로 사용될 수 있는 PLC 기반의FBD 프로그램을 체계적으로 생성하는 기법을 제안하고 있다. 제안된 기법은 기존의 수동 명세 작업에서 발생할 수 있는 오류들을 크게 줄일 수 있으며, 소프트웨어의 개발 비용과 기간을 줄일 수 있다. 또한, 제안된 기법의 유용성을 증명하기 위해서, 현재 KNICS에서 개발 중인 DPPS RPS의 BP를 구성하는 트립 논리 중의 하나인 고정 설정치 상승 트립을 예제로 설명하고 있다.

The software of the nuclear power plant digital control system is a safety-critical system where many techniques must be applied to it in order to preserve safety in the whole system. Formal specifications especially allow the system to be clearly and completely specified in the early requirements specification phase, therefore making it a trusted method for increasing safety. In this paper, we discuss a systematic method, which generates PLC-based FBD programs from the requirements specification using NuSCR, a formal requirements specification method. This FBD programs takes an important position in design specification. The proposed method can reduce the possible errors occur in the manual design specification, and the software development cost and time. To investigate the usefulness of our proposed method, we introduce the fixed set-point rising trip example, a trip logic of BP in DPPS RPS, which is presently being developed at KNICS.

키워드

참고문헌

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