Table of Contents Author Guidelines Submit a Manuscript
Advances in Acoustics and Vibration
Volume 2013 (2013), Article ID 659650, 6 pages
http://dx.doi.org/10.1155/2013/659650
Research Article

Petroleum Pumps’ Current and Vibration Signatures Analysis Using Wavelet Coherence Technique

Advanced Industrial Diagnostic Centre, Digital Signal Processing Research Group, School of Engineering, Manchester Metropolitan University, Manchester M1 5GD, UK

Received 28 February 2013; Revised 7 May 2013; Accepted 22 May 2013

Academic Editor: K. M. Liew

Copyright © 2013 Rmdan Shnibha and Alhussein Albarbar. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Vibration analysis is widely used for rotating machinery diagnostics; however measuring vibration of operational oil well pumps is not possible. The pump’s driver’s current signatures may provide condition-related information without the need for an access to the pump itself. This paper investigates the degree of relationship between the pump’s driver’s current signatures and its induced vibration. This relationship between the driver’s current signatures (DCS) and its vibration signatures (DVS) is studied by calculating magnitude-squared coherence and phase coherence parameters at a certain frequency band using continuous wavelet transform (CWT). The CWT coherence-based technique allows better analysis of temporal evolution of the frequency content of dynamic signals and areas in the time-frequency plane where the two signals exhibit common power or consistent phase behaviour indicating a relationship between the signals. This novel approach is validated by experimental data acquired from 3 kW petroleum pump’s driver. Both vibration and current signatures were acquired under different speed and load conditions. The outcomes of this research suggest the use of DCS analysis as reliable and inexpensive condition monitoring tool, which could be implemented for oil pumps, real-time monitoring associated with condition-based maintenance (CBM) program.