| The operational reliability of small-scale wind turbines in isolated, harsh environments is examined in this thesis. Bell-Aliant operates nearly 40 micro wind turbines (900 W) at hilltop telecommunication tower sites in Labrador, several of which have experienced catastrophic failure, due in part to the extreme meteorological conditions. Consequently, a technological challenge is presented. What are the external forces that caused these failures? Under what circumstances can failure be expected to recur? What, if any, flaws with the machinery may contribute to failure? How may the risk of failure be reduced? This work responds to these questions and in doing so demonstrates a systematic and analytical approach applicable to similar problems. A literature review discusses wind energy technology, applications and the challenges faced when operating in extreme climates. A statistical analysis of site-specific parameters suggests the best indicators of turbine failure potential at a given site were found to he wind speed and turbulence. A forensic mechanical and material analysis of the primary failure mechanism was conducted, highlighting flawed nacelle design. An experimental program whereby turbine response characteristics are analyzed with respect to machine alterations aimed at improving operational reliability showed simple blade modifications are not sufficient to mitigate the primary failure mechanism. |
