Experimental model to control and monitor rotating machines

• Published in: Mechanism and machine theory Vol. 44; no. 4; pp. 761 - 771
• Main Authors: Mahfoud, J., Hagopian, J. Der, Lévecque, N., Steffen, V.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2009; Elsevier
• Subjects: Applied sciences; Control; Drives; Engineering Sciences; Exact sciences and technology; Experimental techniques; Fundamental areas of phenomenology (including applications); Identification; Inverse model; Mechanical engineering; Mechanical engineering. Machine design; Mechanics; Physics; Rotor-dynamic; Shafts, couplings, clutches, brakes; Solid mechanics; Structural and continuum mechanics; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Experimental techniques; Control; Identification; Inverse model; Rotor-dynamic; Force measurement; Rotating machine; Time frequency domain method; Displacement sensor; Measurement sensor; State space; State space method; Experimental study; Real time; Modeling; Real time system; Optimization; Machine design; Least squares method; Displacement measurement; Shaft; Force transducer; Reduced order systems; Monitoring
• ISSN: 0094-114X; 1873-3999
• DOI: 10.1016/j.mechmachtheory.2008.04.009

A method to control and monitor rotating machines is proposed in the present contribution. It is based on the idea of representing the rotating machine by an equivalent reduced model that has to be identified experimentally. The identification is performed by using a limited number of exciting forces and displacement sensors located along the axis of the shaft. An optimization procedure based on the least-squares technique was used. The order of the reduced model (the number of degrees of freedom and modes) corresponds to the number of sensors used. Once the state space matrices are identified, the external excitation forces can be determined in real time for the considered frequency range. The proposed method is assessed numerically and experimentally. The results obtained show the effectiveness of the method proposed. As the determination of external forces is very important in the study of the dynamic behaviour of rotating machines, this inverse model could be easily adapted for monitoring applications.