Analysis of SIL to LSIS Train Control System

다국어 초록 (Multilingual Abstract)

Applying a quantitative approach, this paper demonstrates the results of LSIS (LSIS Co., Ltd.) Safety IntegrityLevel (SIL) allocation for a Train Control System (TCS). TCS is defined in this paper as the set of Automatic TrainProtection (ATP), Automatic Train Operation (ATO) and Computer Based Interlocking (CBI). SIL allocation is performedfor these constituent subsystems of TCS. Systematic approaches for SIL allocation widely used in railway applicationsare compared in terms of the quantity of allocation results. The quantitative method, based on a risk matrix andthe relationship between Tolerable Hazard Rate (THR) and SIL, is more credible than the qualitative method, in thesense that it utilizes more information (e.g., risk reduction factors involved in hazard occurrence) than the qualitativemethod, which purely depends on the configuration of the Risk Matrix Graph. Based on the principles of the quantitativemethod, the SIL allocation process is performed for the subsystems composing TCS. In conclusion, total hazardwas verified such that THR is fulfilled to the corresponding SIL level, which was allocated to each function of ATP,ATO and CBI through quantitative Fault Tree Analysis (FTA) for TCS. THR allocations of each hazard are verifiedbased on calculated failure frequency of the top event. This study has been able to enhance the reliability and safety ofTCS under international standards.

참고문헌 (Reference)

1 장승환, "Study on the Analysis of Safety Integrity Level to Railway Signaling" 대한설비관리학회 20 (20): 69-76, 2015

2 International electronical committee, "Railway applications – Specification and demonstration of reliability, availability, maintainability and safety (RAMS), IEC 62278"

3 International electronical committee, "Railway applications – Communication, signalling and processing systems – Software for railway control and protection systems, IEC 62279"

4 International electronical committee, "Railway applications – Communication, signalling and processing systems Safety related electronic systems for signaling, IEC 62425"

5 International electronical committee, "Fault Tree Analysis (FTA), IEC 61025"

6 P. Gruhn, "Different SIL(Safety Integrity Level) Selection Techniques Can Yield Significantly Different Answers" 2004