Reliability Analysis of Safety Critical Computer System Considering Common Cause Failure

Abstract

The rail transit operation control system and nuclear reactor control system are extremely high for safety and reliability, especially the high speed maglev of more than 600 kilometers per hour. Therefore, the effect of common cause failure on the reliability of safety critical computer must be considered.The safety critical system is the key of the above-mentioned safety demanding system. In this paper, the structure and working principle of a safety critical computer with two-out-of-three and double two-out-of-two are analyzed.Considering the common cause failure and maintenance rate, by using Markov model, the reliability models of safety critical computer system with with two-out-of-three and double two-out-of-two are established. The simulation results show that the existence of common cause failure greatly reduces the reliability of the system. The maintenance rate can improve the reliability of the system. At the same time, considering the common cause failure and the maintenance rate, it is proved that the reliability of the two-out-of-three safety critical computer system is higher than double two-out-of-two safety critical computer system. Therefore, it provides theoretical support for the design of the subsequent differentiated security computer platform.