Review Of The Structure Technique Research On The Wind Generator Set And The Building Of Blades Equivalent Model

Along with the large-size of the wind generator set, the structure dynamics problem of that becomes more important. In this paper, dynamics characteristic of the wind turbine is summarized, including four aspects:(1) Dynamics characteristic, including that of blades,tower and large wind generator system.(2) Fatigue problem, consisting of the source of fatigue load, classification of the fatigue problem and the methods of fatigue resistance design.(3) Stability problem ,consisting of elastic hinge method and aggregative method.(4) The exiting condition of design software of the wind turbine ,including the software widely applied at present.When summarizing the domestic and foreign research methods of the above four aspects, this paper introduces present methods, and new achievement, and these methods are analyzed and compared.Since the shape of the real blades is complicated, it is difficult to establish the physical models directly. If it adopts a simpler model instead of the real blades to do the dynamics analysis, the problem will be simplified. In this paper, referring to the deflection curve, mass and stiffness distribution curve, the blades are simplified to cantilever member in variable cross-section, to be a special beam member. There are many kinds of blades in style, so it is difficult to obtain the general formula of equivalence .But the method in this paper can be consulted.In this paper, the element stiffness matrix of the special beam member in variable cross-section is deduced by energy method; the element mass matrix of that is deduced by principle of virtual work of deformation member.