Comparative Structural and Modal Analysis of a Wind Turbine Planetary Gear Based on Material Cut Criteria using FEM

Compared to other gear systems, the input torque of the planetary gear (speed multiplier) of the wind turbine is bigger than the output torque, and the input speed is less than the output speed, so weight and overall dimensions should be reduced as much as possible to provide a better performance and to ensure a good life cycle of the entire planetary gear. This paper presents the steps completed in order to determine and to compare the stress distributions, the deformations, the displacements and the natural frequencies of the both gear geometries considering the criteria of the material cut on the planet gear using FEM simulations. The obtained results show that the deviation for the stress distribution for the two planet gear geometries (with and without cut) does not exceed a value of 0.4 %, which favors the use of planet gear with material cut.