Modeling and diagnosis for gas turbine lube system

Lube system is one important auxiliary system of the gas turbine, and its operation stability directly related to the security and reliability of gas turbine. Typical faults and its mechanism are analyzed and the mathematic model of lube system is established in MATLAB/Simulink simulation environment, and the variable characteristic parameters of 4 typical faults which are cooler failure, filter block, flow loss due to leakage and damage of lube pump are obtained. Base on the analyzing of signed directed graph (SDG) modeling mythology, the SDG qualitative model of lube system is presented. The states of nodes and branches of lube system SDG Model are quantified by the typical faults simulation results, and the fault diagnostic rule database of lube system are formed. Finally, simulation experiment shows that the SDG fault diagnostic method is feasibility and effective.