Abstract:The multi point fatigue loading system was simplified for the coupling problem occuring in case of wind turbine blade loading multi point excitation. The dynamic mathematical model was established by using the two eccentric block vibration loading as object, constructed electro mechanical coupling equations for the system, and then the electro mechanical coupling was solved by the small parameter cycle average method in resonance conditions. Electromechanical coupling characteristics and stability conditions of vibration system were obtained by the phase plane method. The mechanism of system coupling was revealed. The mechanical and electrical coupling characteristics of primary resonance, system dynamic bifurcation coupling and synchronization control were studied. The coupling characteristics of dynamic bifurcation and its avoidance method were obtained. Finally, the correctness of theoretical analysis through the test, provide guidance for the engineering application of the fatigue loading system, and which provides a reference for similar engineering application and test.
