AN INTELLIGENT BLADE FOR WIND TURBINES

Simulation and testing to develop an Intelligent Blade for wind turbines is presented in this paper. The concept blade has an integrated sensor system for structural health monitoring that will continuously monitor the condition of the blade, warn of initiating damage, and provide instant information that can be used to regulate loading in the blade to reduce or prevent fatigue damage. This can decrease maintenance costs, improve the reliability of wind power, and may make wind energy more affordable. Modeling and simulation of wave propagation in a plate was performed and different configurations of active and passive piezoceramic sensor systems were evaluated and shown to be capable of measuring propagating strain waves and identifying damage. A preliminary experiment to determine the damage detection capability of the sensors was done during a static test of a wind turbine blade. The stress wave propagation characteristics of the blade were monitored as the load level on the blade was increased until blade failure occurred. The effects of the blade stress and curvature on wave propagation need further study, but the results indicate that the technique has the potential for the detection of evolving damage in composite wind turbine blades.

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