I. Introduction
The insatiable demand for the energy together with the rising greenhouse gas emissions push for a dramatic shift towards renewable energy. Of all the renewable sources, wind and solar are at the forefront with minimal contribution from other renewable energy sources such as geothermal, biomass. Wind energy being the key renewable energy source has seen a tremendous growth in the past decades with the total installed capacity of 23GW as of 2016. The total installed capacity of wind turbines is anticipated to supply 3.5% of global electricity demand on 2013 [1] . To meet the projected energy demand through the wind energy, the wind industries are pushed to explore technologies beyond conventional land based installations. Offshore wind turbine is one of the identified potential solutions with significant annual energy output due to high wind speed. Albeit, the wind speeds are relatively higher, yet it bundles with new challenges the industry have not experienced so far.