Research On Condition Evaluation Methods And Fault Diagnosis For Digital Electro-Hydraulic Control System

The condition evaluation and fault diagnosis are important parts for the DEH Control System's condition base maintenance.The main faults of DEH Control System are confirmed by FMEA firstly in the paper, The character parameters of evaluation are distilled according to the main faults. Put the entropy theory and fuzzy theory on the condition evaluation of DEH Control System. It's not only reflects objective datum, but also accord with subjective opinion. This model can be used on the other equipments of power plant usually. And the result of evaluation can afford scientific basis for condition base maintenance.The electro-hydraulic servovalve and oil pump are prone to failure in DEH Control System. Build their model by the modular model on the basis of analyzing their elements, composing, function. Then simulate in the computer use Matlab/Simulink.The results indicate the different faults have the different response curves, the different main faults of DEH Control System can be diagnosis by the different response curves.