A fault backward reasoning method of complex equipment based on Petri nets

Backward reasoning is an algorithm to seek for sufficient conditions of fault based on monitored system level faults. Aiming at characteristics of modern complex communication equipment fault treatment and combining with fault Petri nets theory, a fault backward reasoning method of complex equipment based on Petri nets was presented. The algorithm uses depth-first search (DFS) strategy to access sufficient source fault set cause communication equipment system level fault through access to time record of fault node. Any fault in the sufficient source fault set be solved can solve system level fault. The paper also gives specific steps of the algorithm and analyzes on time and space complexity. Fault diagnosis example based on some large scale communication system verifies the effectiveness of the algorithm.