Research On Fault Analysis Method Based On Digital Prototype For Fluid Circuit System

Fault data is the foundation of fault safety analysis for equipments. However, in thecourse of production, operation and maintenance of the equipments, there is a greatshortage of accumulated fault data owing to various constraints. Meanwhile, thefault-embedded based on a real system is unable to cover most of fault modes becauseof the high cost and low efficiency. Thus, due to the lack of basic data, quantitativeanalysis of fault safety is often difficult to proceed. Therefore, taking propellant fillingsystem as the object, this thesis is to study the modeling of digital prototype and faultsimulation technology based on digital prototype, and try to present a new idea forfault/degradation data acquisition and accumulation.The main work of this thesis is as follows:(1) The research status of digital prototype and fault simulation analysistechnology is investigated and described. The modeling method and software based onbond graph are determined on the basis of comparison in a variety of modelingtechnology.(2) The basic principle, modeling idea, automatic modeling method of bond graphare reviewed, and a brief introduce of AMESim software is given. The method andprocess of co-simulation technique with AMESim and LabVIEW are researched.(3) On the base of module partition, a module library for fluid circuit system isbuilt. Meanwhile, the digital prototype of the propellant filling system is built based onits working principle and structure, and it’s verified to be effective by measured data.(4) The common functional faults are counted while qualitative analysis for faultmode of the key components is presented. And then, the software fault injection methodis discussed. Based on the digital prototype, models on the condition of leak and blockare simulated. Moreover, taking the ball valve after1#pump for instance, performancedegradation process of key component is also studied and simulated.In a word, the modeling and simulation technology of digital prototype and thebasic dynamical foundation of fluid circuit system are studied in this thesis. Takingpropellant filling system for instance, a digital prototype is built to simulate the typicalfault states and degradation process, and the results are effective.