In view of the unreasonable structural load distribution of direct-drive wind turbines and the frequent occurrence of tower breaking accidents

this paper improves the structure of direct-drive wind turbines based on the load distribution of direct-drive wind turbines. The mechanical analysis on the structures before and after the improvement is conducted

and the loaddistribution is calculated. The static analysis and prestress modal analysis of the structures before and after the improvement are carried out by using the finite element software. The comparative analysis results show that the maximum displacement after the improvement is reduced by 532.74 mm

the reduction is about 37.68%

and the relative tower height displacement is reduced by 0.33%. The maximum stress after improvement is 141.74 MPa

which is 81.43 MPa lower than that before improvement

with a decrease of about 36.48% and a decrease of 14.81% in the allowable stress. The vibration mode difference of tower drum structures before and after improvement is small

and the vibration mode rule is the same. After the improvement

the natural vibration frequency of the tower structure has increased

but the maximum change is only 0.000 08 Hz.