Capstone project

Wind turbine generator tower

The manufacturers of small wind turbine generators specify required maintenance procedures for their products. However, currently available generator towers do not provide for a safe means of access to the turbine generator. Tower manufacturers recommend either to climb the tower or to lower the entire tower to the ground. The tower design presented in this report was modeled to support a 3 KW turbine generator weighing 155 lbs. This design incorporates a thirty-foot freestanding tubular tower with a pivot point, which allows the turbine to be lowered to the ground for maintenance and inspection. This tower design was analyzed for fatigue life, shear stress, bending stress and buckling potential. Additionally, a model was constructed and tested for wind loads up to 130 MPH. Wind loads on the tower and the turbine were considered. It was found that the endurance limit of the tower material occurs at loads expected with winds of 125 MPH. Therefore fatigue was not considered to be a limiting factor in this design. Shear stress was considered to be negligible, representing less than 2% of the bending stress expected. The analysis of buckling potential revealed that the applied loads represent only 1.8% of P[critical]. The potential for buckling was therefore considered to be negligible. Bending stress at 130 MPH reaches the material yield point. Model testing resulted in stress values 11 to 13% higher than calculated values for wind loads above l00MPH.