Anomaly Detection in Turbine Using Blade Vibration Measurement With SAW Sensor

This paper is focused on a new method of noncontact turbine blade vibration measurement using a surface acoustic wave sensor (SAW)-based sensor. The SAW-based vibration sensor is mounted on the rotating blade of the turbine, and the SAW interrogation device is mounted on the stator blade. The SAW sensor freely moves along with the blade of the turbine. The output of the sensor is transmitted to the interrogation unit placed in the stator blade through an antenna. Due to the fast rotation of the blade, vibration may be generated. The generated vibration is captured by the SAW sensor, which gives the response of the vibration in terms of the frequency shift. The response of the SAW sensor is accessed by the SAW interrogation unit. The reference resonant frequency used here is 433 MHz, which comes under the industrial, scientific, and medical radio (ISM) band. The dimensions of the sensor are in the range of millimetres, so it does not affect the rotation of the turbine blade. The saw sensor does not require any on-board power supply, and it can withstand temperatures around $1000^{\circ}\mathrm{C}$.