Stability analysis of a wind turbine tower using reachability properties of switched systems

Wind turbines are increasingly installed to generate electricity around the whole, as an alternative energy source to conventional fossil fuels in order to reduce fossil fuel energy dependence and environment impact. It is well known that wind towers must be designed to sustain continuous vibration forces throughout their operational life, which are more critical at offshore locations. The paper aims to analyze the structural stability of a wind turbine tower made of steel. The wind turbine tower is modeled as the addition of various (infinitesimal) simplified beam-columns, which mathematically can be represented by a switched system. Each beam-column section is equivalently modeled as a Hamiltonian system which allows simplifying the system and providing the stability general response. An eigenvalue analysis has been done in order to analyze the stability of the system; finally, also, some transient simulations of the system are presented to verify the results obtained.