INSTANTANEOUS POWER AS A TOOL TO DETECT A FAULT IN A DOWNSTREAM MACHINE

Abstract

This paper concerns the possibility of detecting a fault in a downstream machine via the instantaneous power of the drive motor. The proposed method is investigated experimentally throughout a test rig designed to simulate different faults. The considered fault in this study is a tooth breakage in three stages gearbox. However; two degrees of tooth breakage were seeded in the gearbox by machining quarter and half tooth in the pinion helical gear. Using a data acquisition system the data of the motor  instantaneous power was acquired under healthy and faulty operating condition at three different loads. The acquired data was processed through a MATLAB code where the instantaneous power signal investigated both in the time and frequency domain. The obtained results have shown that this approach is capable to detect a small tooth breakage in a downstream gearbox but incapable to diagnose such fault.

Keywords: dawnstrem; gearbox; monitoring; detection; helical gear; power.