To study the dynamic response characteristics of the wind turbines under typhoons, an involvement of the complex coupling of multiple models and methods from different disciplines is needed. A lot of research has been done that mainly focused on the models calculating the aerodynamic loads [7; 8; 9; 10; 11; 12], the dynamic models calculating the effect on the complete wind turbine [13; 14; 15] and aeroelastic analysis methods [16; 17; 18]. However, there are a few studies that compare the reliability and accuracy of a simulating typhoon wind field. [PERSON] [19] measured the whole process of typhoon from landing to departure. It is found that the turbulence intensity and turbulence integral scale at different times are significantly different. The power spectrum fitted by the measured data is quite different from the Von Karman spectrum in the low frequency part. According to the measured data of typhoon Usagi, [PERSON] [20; 21; 22] fitted the wind profile to construct the wind field of typhoon using solely the average speed, and carried out the static analysis of wind turbine. In other reports, the fluctuating wind field was simulated by combining the power spectrum and the wind profile [23; 24]. The spectrums used in these simulations are fitted according to the data of the normal wind. [PERSON] [25] combined the typhoon profiles with the CFD (Computational Fluid Dynamics) method to improve the accuracy of aerodynamic calculation of wind turbines, but the power spectrum of the typhoon was not used when the turbulence characteristics of far-field boundary are input, and the calculation amount of this method is huge. Based on the above research findings in literature, there is significant room for the improvement in accuracy of the typhoon fluctuating wind field simulation.  
On the other hand, the wind direction in the eyewall region of the typhoon varies dramatically [26]. Although the wind turbine would be shut down in typhoons, and the yaw system would still be in working condition so as to adjust the position of the rotor to keep it against the incoming flow, there still exists a delay for a certain period of time (typically, 10 min) due to the statistical time consumed for the wind direction changes [27]. Therefore, the wind turbine may run for a long time at large yaw angle under typhoon, which will bring serious hazards in terms of structural safety of the wind turbine blades and towers. At present, most of the research working on the impact of yaw on wind turbines focuses on the aerodynamic performance affected by the yaw-induced inclined wake on blades [28; 29; 30]. There are a few further studies on the vibration response and structural damage caused by yawing of wind turbines. It was found that, when the deflection of the incoming flow reached 30 degrees and 40 degrees, the thrust of the wind turbine changed by 17% and 44%, respectively [31; 32]. When the yaw angle was between 40 and 50 degrees, the wind turbine blades stalled. The vibration response analysis of the wind turbine under various conditions was carried out based on experiments, which showed that the existence of yaw angle increased the vibration of the blades at low natural frequencies [33]. Through the structural health monitoring [34; 35], it was found that the yaw angle affected the dynamic response of the wind turbine blades in a frequency domain that changed to lower frequency. Once the wind turbine exhibited a significant yaw in extreme weather, it would lead to an increase in the tower stress with a risk of being damaged.  
Figure 1: The schematic of typhoon structure.  
In view of the shortcomings of the current research, this paper combines the measured data of typhoon eye wall region with the power spectrum method to simulate the fluctuating wind with typhoon characteristics, and combines them with the aerodynamic and dynamic models of the wind turbines to study the aeroelastic response characteristics of wind turbines with different yaw angles.