Modeling Based On Bond Graph Theory, Two-stage Matrix Converter Excited Doubly-fed Wind Power Generation System

Consisting of multiple assembly parts,like wind turbine,shaft-system,excitation device(ED) and generator,variable-speed constant-frequency wind-power generation system(VSCF-WPGS) is a complex system involving many fields of acknowledge.Most studies with it locally begin,in other words,the establishment of sub-component'mathematic model takes the modeling method of the discipline the sub-component belongs to.As a result,it is difficult to obtain global kinetic model.Generally speaking,Mathematic model has its own disadvantages,like divorcing from practical physical meaning and incapability of visual analysis.As a method capable of dynamically analyzing engineering system,the internal mechanism of Bond Graph (BG) is that it represents the transportation,transformation,depositing and dissipation of power among the system as graphics by itself.It is specially suitable for modeling complex system coupled by various categories of energy.This thesis studies the modeling technology of VSCF-WPGS based on BG.After a thorough analysis to the structure and behavior of the system of doubly-fed WPGS excited by the two-stage matrix converter(TSMC), the establishment of its BG model of four main sub-components is investigated.Focusing on the building of BG models of TSMC and doubly-fed electrical machine(DFEM),the description of ideal switch using the Switched Power Junction is presented and BG models of TSMC and DFEM under rotating frame are given and validated on the platform of the 20-sim software.Based on the above study,the building of BG model of the whole WPGS and how to analyze the set-up Bond graph using temporal causal graph are explored.The above work extends the application study of BG model in the field of power electronics system and provides a brandnew method for modeling WPGS.It is very convenient to dynamically analyze WPGS by means of the set-up BG model.