Rotor blades, like aircraft wings, are essentially cantilevered beams with aerodynamic exteriors. Early blades were made of wood. More recently, they consist of fiberglass and epoxy resins manufactured by reaction injection molding in rather complex equipment. The quest for greater power will demand longer blades which has led designers to examine carbon fibers as a…

To improve the efficiency of large turbines, many operators have turned to a rather small, 58-mm dia. absolute encoder from Denmark’s Leine&Linde. The Model 500 series of Incremental and absolute encoders provide speed and positioning  feedback to controls in nacelles. Siemens wind turbines, for example, use a pulse encoder on each rotor blade and one…