Instantaneous Purified Orbit: A New Tool for Analysis of Nonstationary Vibration of Rotor System

• Main Authors: Shi Dongfeng, Qu Liangsheng, Bao Ming
• Format: Article
• Language: English
• Published: Hindawi Limited 2001-01-01
• Series: International Journal of Rotating Machinery
• Subjects: Fault diagnosis; Time-frequency analysis; Rotor system; Nonstationary vibration.
• Online Access: http://dx.doi.org/10.1155/S1023621X01000094

In some circumstances, vibration signals of large rotating machinery possess time-varying characteristics to some extent. Traditional diagnosis methods, such as FFT spectrum and orbit diagram, are confronted with a huge challenge to deal with this problem. This work aims at studying the four intrinsic drawbacks of conventional vibration signal processing method and instantaneous purified orbit (IPO) on the basis of improved Fourier spectrum (IFS) to analyze nonstationary vibration. On account of integration, the benefits of short period Fourier transform (SPFT) and regular holospectrum, this method can intuitively reflect vibration characteristics of’a rotor system by means of parameter analysis for corresponding frequency ellipses. Practical examples, such as transient vibration in run-up stages and bistable condition of rotor show that IPO is a powerful tool for diagnosis and analysis of the vibration behavior of rotor systems.