A comparative study of acoustic, vibration and stator current signatures for gear tooth fault diagnosis

The condition monitoring of a gearbox is an important task due to its significance in the mechanical power transmission in industrial applications. The vibration analysis has been commonly used as an effective tool for gear fault diagnosis in several researches. Other alternatives, such as stator current analysis or acoustic pressure analysis which are known as non-invasive methods have received great attention over the years. The effect of gearbox torsional vibration in the stator current has been recently studied based on real frequency components observation in the mechanical torque. A possible monitoring of gearbox-based electromechanical system through the stator current analysis has been investigated as well. This paper aims to provide a comparative study of vibration, acoustic pressure and stator current analysis capabilities for a gear tooth wear fault diagnosis. A test-rig based on a 250W squirrel-cage induction machine shaft-connected to a single-stage gearbox has been used for this purpose.