Wind Turbines

Wind energy occupies a leading place among renewable energy sources for electric power system generation. The cumulative installations of wind turbines are continuously growing, and last year the cumulative capacity increased by nearly 11%, to around 539 GW [Wind Energy Systems. Proceedings of the IEEE, 2017], and it is expected to transcend 760 GW by 2020 [Renewables 2018 Global Status Report—REN21]. Today, the global installed renewable generation capacity has passed 2000 GW, where hydro-power counts for around 1000 GW.

Moreover, in 2017, the offshore wind power sector had its best year yet and its total capacity increased by 30%. This constant increase in the rapid pace of wind power is due to significant technological achievements in recent years, and it has made it possible to lower the cost of energy dramatically from that coming from wind turbines. The size of wind turbines continues to increase, and several manufacturers have announced plans to produce wind turbines of 10 MW and larger [Wind Energy Systems. Proceedings of the IEEE, 2017]. All of the above is achieved through technological advancements, including advanced wind speed prediction; advanced control methods; power electronics and its control; advanced manufacturing techniques; new materials, but also fault detection and diagnostic methods, which can provide a high level of reliability; availability; maintainability; and safety for the wind turbines. The competition between the different renewable energy sources is intense—photovoltaic power is constantly pushing the limits of lowering the cost of energy—and thereby also challenges wind power technology to come up with better and more cost-effective solutions.