From a distance, wind turbines have an aura of lofty silence about them as their huge rotor blades turn sedate circles in the air. But up close the reality is rather different. Wind turbine blades vibrate. In fact every wind turbine has its own unique blade vibration pattern – like a fingerprint – which furthermore can be analysed to ascertain how well (or how badly) the turbine is performing.
Collecting this vibration information has an obvious value to energy companies operating wind farms, but it has the drawback of requiring cabling in the blades and supplementary power sources to collect and transmit the information from installed sensors. Extra components mean extra cost and extra complexity in an already highly complex machine.
But as professional journal Ingeniøren (The Engineer) reports, there could now be a smarter solution on the way. In collaboration with DTU Nanotech, the Danish company Ferroperm Piezoceramics has discovered a piezoelectric means of turning blade vibrations of any frequency into electricity which can be used to power vibration sensors and transmit the information wirelessly to a remote monitoring centre.
Denmark's Vestas, the world's leading manufacturer of wind turbines, has expressed interest in using this system to collect data from its wind turbines worldwide, and now the three parties have formed a consortium to develop a prototype, with DKK 12m (USD 2.25m) in support funding over the next three years being provided by the Danish High Technology Foundation.
Ferroperm Piezoceramics' development director Erling Ringgaard sees considerable potential in its piezoelectric invention. He commented to Ingeniøren: "When we have demonstrated that [the system] works for wind turbines, it will be natural to look at other difficult-to-access areas where there is a need for advanced measurements. The aircraft industry is an obvious example, but there could be many others."