A Comparative Study of Vibration Frequency Estimates of the Surface Foundations of Wind Turbines Built on the Sand Dunes of the Ceará Coast

This paper aims at presenting a comparative study of vibration frequency estimates of the surface foundations of wind turbines built on the sand dunes of the Ceará coast. Initially, some basic concepts of foundation dynamics will be addressed along with the main methods available in the literature for the calculation of vibration frequencies of rotational machines. A comparative study shall also be presented of vibration frequency estimates of surface foundations of wind turbines of two wind farms located on the coast of Ceará using different methods.