Fuzzy Fault Tree Analysis of Conventional Propellant Temperature Control System

Fuzzy fault tree analysis method is applied to study the reliability of the conventional temperature control system. Firstly, fault tree model of the conventional temperature control system is established. Secondly, based on the fuzzy mathematics theory, ascending method is applied to solve the minimum cut set of the fault tree. The expression of bottom event occurrence probability is described by normal type fuzzy numbers, and the calculation method of top event fuzzy sets is put forward. Finally, a fault location and screening method based on the fuzzy probability importance is provided. PLC communication faults are calculated and analyzed as an example. The results show that the troubleshooting methods based on the fuzzy probability importance can effectively improve the efficiency of fault location.