Abstract: Study on planetary gear dynamics in a wind turbine is of great significance to reduce the vibration and noise, extend the service life and improve the operation reliability. Besides the complicated structure, rich nonlinear factors and internal excitations, the planetary gear train has complex external wind load. Many scholars at home and abroad have done many thorough researches. From system modeling, dynamic equation, dynamic characteristics and dynamic optimization design, the development on planetary gear dynamics is reviewed. The progress of dynamic characteristics is introduced in detail from modal properties, parametric instabilities and nonlinear dynamic responses. The main nonlinear factors are backlash, bearing clearance and tooth surface friction. According to the specific working environment and development trends of planetary gear trains in a wind turbine, some critical issues deserving further research are also pointed out.

Key words: planetary gear trains;solving algorithms;dynamic model;dynamic characteristics;optimization design