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Abstract

Elementary hydraulic switching control aiming at energy efficiency can be done by connecting a hydraulic cylinder alternately with a high pressure and a tank line in a pulse width controlled mode. The switching frequency is crucial for the energetic efficiency as well as for the speed fluctuation of the generated motion. This paper clarifies why and in which way the efficiency optimal switching frequency is related to some resonance condition. A simple non-linear, non-dimensional, second-order differential equation is derived that represents the dynamic behaviour of the drive system. It is investigated by asymptotic expansion methods. If valves with a relatively small nominal flowrate are used the optimal frequency is close to the natural frequency of the load oscillating in the hydraulic cylinder's compressible hydraulic fluid. Larger valves enable higher efficiency and weaken the role of resonance. The optimal frequency becomes smaller.

Keywords

hydraulic switching control hydraulic drives asymptotic expansions resonance

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References

Gall

Senn

Freilaufventile—Ansteuer-ungskonzept zur Energieeinsparung bei hydraulischen Linearantrieben. O+P

“Olhydraulik und Pneumatik”, 1994, 38 (1–2), 38–43.

Scheidl

Schindler

Riha

Leitner

Basics for the energy-efficient control of hydraulic drives by switching techniques. In Proceedings of the 3rd Conference on

Mechatronics and Robotics, Paderborn, Germany, 4–6 October 1995, pp. 118–131 (Teubner, Stuttgart, Germany).

Scheidl

Realisierung von Schalttechniken für ölhydraulische Antriebe durch Nutzung resonanter Wellen. E&I, 1996, 113, 553–558.

Garstenauer

Scheidl

Fast hydraulic switching valves—key components for the introduction of switching techniques in oil hydraulic drives. In Proceedings of 3rd International Heinz Nixdorf Symposium, Paderborn, Germany, May 1999, pp. 281–294.

Nayfey

A. H.

Introduction to Perturbation Techniques, 1981 (John Wiley, New York).

Kevorkian

Cole

J. D.

Perturbation Methods in Applied Mathematics, Series on Applied Mathematical Sciences, Vol. 43, 1980 (Springer-Verlag, Berlin, Germany).

Eckhaus

Asymptotic Analysis of Singular Perturbations, 1979 (North Holland, Amsterdam, The Netherlands).

Scheidl

Riha

Energy Efficient Switching Control by a Hydraulic ‘Resonance Converter'. In Bath Workshop on Power Transmissions and Motion Control (PTMC'99) (Eds Burrows

C. R.

Edge

K. A.

), 1999 (Professional Engineering Publishing, London and Bury St Edmunds).

10.

Wong

Ch.

Brown

A. D.

Analysis, modeling, and simulation of series-parallel resonant converter circuits. IEEE Trans. Power Electronics, 1995, 10, 605–613.

The role of resonance in elementary hydraulic switching control

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