Adaptive time–frequency decomposition for transient vibration monitoring of rotating machinery

Monitoring the vibration behaviour of large rotating machinery is an effective way to reduce production losses and enhance safety, efficiency, reliability, availability and longevity in manufacturing processes. As large rotating machinery is increasingly employed in continuous operations at high speeds and with heavy loads, the vibration behaviour of the rotor systems is more and more complex. Focusing on the defects of different joint time–frequency representations, we present an adaptive time–frequency decomposition (ATFD) technique to describe transient vibration. This approach provides a precise interpretation of complex signals that consist of various time–frequency structures through decomposing it into paramedic, redundant and well-localised components in the time–frequency plane. Both computer simulation and an actual case show that this technique has high time–frequency resolution and no interference terms. The analysis results proved this approach could specify critical speed as well as acceleration rate accurately and is very effective in ensuring machinery passing through critical speed field safely. r 2003 Elsevier Ltd. All rights reserved.