Wind turbines under atmospheric icing conditions - Ice accretion modeling, aerodynamics, and control strategies for mitigating performance degradation

This paper presents an efficient engineering methodology to study the performance of wind turbines subject to atmospheric icing conditions. The Turbine Icing Operation Control System (TIOCS) is based on strip theory for both ice accretion and aerodynamic modeling. Small amounts of accreted ice on the order of a few percent of the sectional airfoil chord are considered. The TIOCS methodology can serve the wind industry and wind turbine operators by providing guidelines for wind turbine operation during and post moderate icing events. Preliminary results obtained for the NREL Phase VI rotor and the in-house designed utility-scale PSU-2.5 wind turbine subject to a representative icing condition indicate that alterations in performance due to surface icing can be mitigated through appropriate control strategies during and post an icing event.