A time-encoded signal-processing approach to fault classification of an electrohydraulic pressure control system and its application to a hot steel strip rolling mill

Abstract

A technique is presented whereby time domain signals may be classified in terms of four shape parameters. These parameters are processed to create a condition indicator, its variation being used to identify system faults. In this study, the leakage flowrate and a faulty servo-valve are identified on a pressure control system and a comparison is made with a conventional fast Fourier transform approach and a commercial software package, time-encoded signal processing and recognition. A new code, CARCODE, is then applied to 28 servo-valve-controlled work roll bending circuits on a seven-stand hot steel strip rolling mill and a simple graphics presentation is developed to aid real-time condition monitoring.

Keywords

fault diagnosis fluid power control time-encoded signal processing

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References

Darling

Tilley

D. G.

Progress towards a general purpose technique for the condition monitoring of fluid power systems. In Proceedings of the IMechE Seminar on

Aerospace Hydraulics and Systems, London, 1993, pp. 47–55 (Mechanical Engineering Publications Limited, London).

Watton

Kwon

K. S.

Neural network modelling of fluid power control systems using internal state variables. Mechatronics, 1996, 6 (7), 817–827.

T. T.

Watton

Pham

D. T.

An artificial neural network level approach to fault diagnosis and classification of fluid power systems. Proc. Instn Mech. Engrs, Part I, Journal of Systems and Control Engineering, 1997, 211 (I4), 307–317.

T. T.

Watton

Pham

D. T.

Fault classification of fluid power systems using a dynamic features extraction technique and neural networks. Proc. Instn Mech. Engrs, Part I, Journal of Systems and Control Engineering, 1998, 212 (I2), 87–97.

Requicha

A. A. G.

The zeros of entire functions: Theory and engineering applications. Proc. IEEE, 1980, 68 (3), 308–328.

Holbeche

Hughes

R. D.

King

R. A.

Time encoded speech (TES) descriptors as a symbol feature set for voice recognition systems. In Proceedings of the IEE International Conference on

Speech Input/Output Techniques and Applications, London, 1986, pp. 310–315 (Institution of Electrical Engineers, London).

Rodwell

G. M.

King

R. A.

TESPAR/FANN architectures for low power, low cost condition monitoring applications. In Proceedings of COMADEM, 1996, pp. 1089–1101 (Sheffield Academic Press, Sheffield).

Gale

Watton

The implementation of an on-line computer system for the condition monitoring of the hydraulic performance of a hot strip steel finishing mill. In Proceedings of the Fifth International Conference on

Fluid Power, Linköping, Sweden, 1997, pp. 397–411.