Fault Diagnostic Expert System Of Turbine Generator Sets Based On Models

A major accident occurred in the steam turbine generator set can cause great losses to the society and the economic development. It put forward higher requirements for the safety monitoring ability of the operation status to make sure the security, stable and efficient operation of large steam turbine generator unit. Research and development of fault diagnosis expert system for steam turbine generator unit is helpful for steam turbine generator unit to diagnose and prognose failure accurately and efficiently. It also of great significance for monitoring the good working conditions.The main contents include:(1) The expert system based on the model and rule case reasoning are compared. On the basis of the advantages and disadvantages of the two meth ods. An integrated inference mechanism of fault diagnosis based on model and rule reasoning is proposed.(2) Fault model database for fault diagnosis expert system of steam turbine generator set is constructed. It is established by the simplified model of the turbo generator rotor system of three typical fault models such as rotor misalignment, rub and bending. Then dynamic models of three typical fault are also built and the differential equations of motion of the rotor are obtained. Through numerical simulation results, the vibration characteristics of each fault are summarized. The model base of fault diagnosis expert system for the turbine generator set with the above three kinds of faults is established.(3) Analyzing the practical situation of steam turbine generator rotor system, a kind of oil film force model for tilting-pad bearing is put forward in paper, which considered the process parameters such as turbulence coefficient, viscosity coefficient. Based on the model, the dynamics differential equations of the rotor system with rubbing fault of tilting-pad bearing is established. And the accuracy of the model is verified with result in the rotor test rig.(4) A fault diagnosis expert system for steam turbine generator set is designed and developed by using CLIPS, Visual Studio C#, SQL Server and MATLAB. Combining with their respective advantages of four software mixed development, the research and development of expert system speed up effectively. Finally, the expert system is tested by severed cases, the practicability and reliability of the system is verified.