Wind turbine blade health monitoring with piezoceramic-based wireless sensor network

In this paper, a piezoceramic-based wireless sensor network (WSN) was developed for health monitoring of wind turbine blades with active sensing approach. The WSN system has an access point that coordinates the network and connects to a PC to control the wireless nodes. One wireless node functions as an actuator to excite an embedded piezoceramic patch with desired guided waves. The remaining wireless nodes function as sensors to detect and transmit the wave responses at distributed locations. The damage status inside the blade was evaluated through the analysis of the sensor signals. Based on wavelet packet analysis results, a damage index and a damage matrix were developed to evaluate the damage status at different locations. To verify the effectiveness of the proposed approach, a static loading test and a wind tunnel test were performed in the Laboratory of Joint Wind Tunnel and Wave Flume at Harbin Institute of Technology (HIT), China. Experimental results show that damage in wind turbine blades can be detected and evaluated by the proposed approach.