Wind Turbine Rotor Blade Ice Detection via Drive Excitation

The patent applies mechanical vibration by exciting the rotor blade with oscillations from the pitch drive and recording these vibrations with sensors. By analyzing the natural frequencies and oscillation patterns of the blade, the system can detect ice build-up or damage without requiring high-resolution sensors. The vibration-based approach transforms the detection problem into a frequency analysis problem that can be solved with simpler, more cost-effective sensor technology.

The patent employs periodic action by utilizing the regular, cyclic oscillations generated by the pitch drive during normal operation. These periodic movements naturally excite the rotor blade at its resonant frequencies, providing consistent vibration patterns that can be recorded and analyzed. This approach ensures detection capability is maintained during low-wind or stationary conditions without requiring additional energy input or external excitation sources.

The patent applies universality by making the pitch drive serve a dual function: its primary function of adjusting blade pitch for optimal wind energy capture, and a secondary function of exciting oscillations for ice build-up and damage detection. By leveraging the existing multi-functional capability of the pitch drive, the system achieves reliable detection without adding separate excitation mechanisms, thereby maintaining detection reliability while minimizing additional device complexity.