Analysis of Icing on Wind Turbines by Combined Wireless and Wired Acceleration Sensor Monitoring

Rotor blade icing negatively affects the operation of wind turbines and its electricity generation. The ice layer increases the blade masses, influences aerodynamics, and can fall off anytime during rotation with unpredictable trajectory and impact on ground. Due to this potential risk to human life, operation needs to be interrupted. Turbines equipped with blade heating face a downtime of some minutes to hours until removal of ice and restart of operation. Older turbines without heating system might stand still for a longer duration, resulting in significant loss of generated electricity. Modern Supervisory Control And Data Acquisition (SCADA) systems either detect icing by sophisticated measurement systems in the rotor blades, for example fiber Bragg grating devices, or predict the presence of ice by a combination of measured moisture, temperature and wind speed. Wireless acceleration sensors on the turbine tower may detect icing, monitor ice growth and even predict time of alert. The present work discusses the surveillance of an existing power plant by both wireless and wired acceleration sensors in parallel to the ice alerts of the turbine’s SCADA system and change of key parameters for indication of icing status.