A strategy and technologies for blade health management from manufacturing to operation

Wind energy is a form of renewable energy which has gained much attention due to the need for clean and inexpensive energy source. With the need for more energy, the size of wind turbines has become physically larger making the maintenance and repair work difficult. Thus there is a need to perform the quality control of blades during the manufacturing to ensure the production of defect-free wind turbines. An ultrasonic wave propagation imaging (UPI) system that uses Q-switched laser (QL) ultrasonic scanning excitation and piezoelectric sensors has been devised and implemented for the in-process quality control of blades. This technology can be used as a smart factory concept for real-world application to detect any damages in the wind blades during the manufacturing process. To improve safety during operation, to minimize the risk of sudden failure and to ensure reliable power generation, a structural health monitoring technology is required during the operation as well. Thus, this study also proposes a single laser displacement sensor (LDS) system in which all of the rotating blades could be cost-effectively monitored during its operating condition. It is impractical to monitor the wind blades very high above the ground level or in offshore condition through wired connection, so we have devised a wireless solution using Zigbee technology. The output from the LDS is fed to analog to digital converter (ADC) which is connected to Zigbee transceiver module that transmits the data to the remote location for real time monitoring of wind blades.