Stress diagnostic and monitoring of blade in rotational motion.

With increasing need for green energy sources and rising popularity of small horizontal axis wind turbines in micro electric installations for household and industrial purposes, the safety measures are gaining supreme interest. Small wind turbine built within the frames of GUST (Generative Urban Small Turbine) project developed by Lodz University of Technology, is an example of such multi-level, security-oriented design. The machine is equipped with fully functional modules and software working on constant supervision of electric and electronic components of the wind turbine. In case of any possible failure mark detected, automated braking system is triggered to stop the rotor. Taking the safety system one step further, there is also a need for monitoring of mechanical aspects of rotor operation, such as blade deflection. To check this aspect, on a surface of the blade based on SG6043 aerofoil we have installed a strain gauge system. Then, a dedicated electronic circuit was developed for data acquisition and storage. Together, they create a fully functional system of blade deflection measurement. The purpose of this article is to introduce our idea to the reader, present the preliminary results followed by signal analysis and show the prospects for improvements in the future. [ABSTRACT FROM AUTHOR]