Design evaluation of hardwired F-LIC module for ITER AC/DC converters by FMEDA method

The Fast Local Interlock Controllers (F-LIC) are important components for the fast protection of ITER AC/DC converters and super conducting coils in the event of quench or converter faults. When the quench signal or converter fault is detected over the threshold set-point, it triggers fast bypass switch, gate block switch, Make Switch and/or Protective Make Switch (MS-PMS) and Circuit Breaker (CB) trip for the protection. To meet the requirements of the ITER local interlock system, the F-LIC design should assure that its safety integrity is attained by evaluation of the Safety Integrity Level (SIL), as per IEC 61508. The design and evaluation of the F-LIC of ITER AC/DC converters have been studied and developed in Korea Domestic Agency (KO-DA) of the National Fusion Research Institute (NFRI) and Dawonsys Corp. In this paper, the hardwired F-LIC design is introduced and the SIL analysis of the F-LIC module has been performed to meet the requirements of IEC 61508. The Failure Mode, Effect, and Diagnostic Analysis (FMEDA) technique is used for the evaluation method.