An RC filter for hydraulic switching control with a transmission line between valves and actuator
DOI:
https://doi.org/10.13052/14399776.2014.970974Keywords:
digital hydraulics, hydraulic switching control, hydraulic RC filter, pulsation attenuationAbstract
Hydraulic switching control with fast switching valves may excite unacceptable hydraulic and mechanical oscillations. Particularly if transmission lines are used, which have many oscillation modes, the avoidance of resonances by a proper timing of the switching pulses is hardly feasible. Then, passive filters may be a good solution. A simple RC filter applied to a cylinder drive with a transmission line to the switching valves is investigated by a transfer function analysis, numerical methods, and experiments. Properties of the dynamic behaviour are elucidated by approximate relations derived from the transfer function by asymptotic methods. A simple dimensioning rule recommends sizing the filter resistance close to the hydraulic impedance of the transmission line. The capacitance’s sizing is a trade off between a potential reduction of the resonance peak due to the cylinder natural frequency and a softness of the hydraulic drive system.
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References
Brown, F.T., 1987. Switched reactance hydraulics: a new way
to control fluid power. In: National conference on fluid
power. Chicago: NFPA, 25–34.
Brown, F.T., Tentarelli, S.C., and Ramachandran, S., 1988. A
hydraulic rotary switched-inertance servo-transformer.
ASME Journal of Dynamic Systems, Measurement, and
Control, 110 (2), 144–150.
D’Souza, A. and Oldenburger, R., 1964. Dynamic response of
fluid lines. ASME, Journal of Basic Engineering, 86,
–598.
De Negri, V.J., et al., 2014. Behavioural prediction of hydraulic
step-up switching converters. International Journal of Fluid
Power, 15 (1), 1–9.
Edge, K.A. and Johnston, D.N., 1990a. The secondary source
method for the measurement of pump pressure ripple characteristics.
Part 1 – Description of Method. Proceedings of
the Institution of Mechanical Engineers, Part I: Journal of
Systems and Control Engineering, 204, 33–40.
Edge, K.A. and Johnston, D.N., 1990b. The secondary source
method for the measurement of pump pressure ripple characteristics.
Part 2 – Experimental results. Proceedings of
the Institution of Mechanical Engineers, Part I: Journal of
Systems and Control Engineering, 204, 41–46.
Gradl, C. and Scheidl, R., 2013. A basic study on the response
dynamics of pulse-frequency controlled digital hdyraulic
drives. In: E. Barth, and A. Vacca, eds. The Bath/ASME
Symposium on Fluid Power & Motion Control,
FPMC2013, 6–9 October, Sarasota, Florida, paper ID:
FPMC2013-4438.
Hayward, A.T.J., 1976. A linear orifice-plate flowmeter.
Journal of Physics E: Scientific Instruments, 9,
–442.
HydroLib3, 2014. http://imh.jku.at [Accessed 20 June 2014].
Kogler, H., 2012. The Hydraulic Buck Converter – Conceptual
Study and Experiments. ACCM Schriftenreihe Advances in
Mechatronis, Bd. 16, Trauner Verlag, Linz.
Kojima, E. and Ichiyanagi, T., 1998. Development research of
new types of multiple volume resonators. In: C.R. Burrows,
and K.A. Edge, eds. 1st Bath Workshop on Power Transmission
and Motion Control (PTMC 1998), Bath, UK,
–206.
Kribayashi, T., et al., 2010. Research on the attenuation characteristics
of a multi-degree of freedom type Helmholtz Resonator
for hydraulic systems. Proceedings of Mechanical
Engineering Congress 2010 Japan, 7, 79–80.
Linjama, M., 2011. Digital fluid power – state of the art. In: H.
Sairiala, and K.T. Koskinen, eds. The Twelfth Scandinavian
International Conference on Fluid Power, 2 (4), SICFP’11,
–20 May, Tampere, Finland.
Linjama, M., Huova, M., and Vilenius, M., 2007. On stability
and dynamic characteristics of hydraulic drives with distributed
valves. In: D.N. Johnston, and A.R. Plummer, eds.
Power Transmission and Motion Control (PTMC 2007),
–14 September University of Bath, UK. 297–314.
Manhartsgruber, B., 2010. The influence of transmission line
dynamics on the performance of digital flow control units.
The third workshop on digital fluid power, DFP’10, 13–14
October 2010. Finland: Tampere, 107–118.
Mikota, J., 2001. A novel, compact compensator to reduce
pressure pulsations in hydraulic systems. In: Proceedings of
ICANOV – International conference on noise, acoustics
and vibration. Ottawa, Canada.
Ortig, H., 2005. Experimental and analytical vibration analysis
in fluid power systems. International Journal of Solids and
Structures, 42, 5821–5830.
Pan, M., et al., 2014. Theoretical and experimental studies of a
switched inertance hydraulic system. Proceedings of the
Institution of Mechanical Engineers, Part I: Journal of Systems
and Control Engineering, 228 (1), 12–25.
Plöckinger, A., Scheidl, R., and Huova, M., 2012. Simulation
and experimental results of PWM for digital hydraulics. In:
A. Laamanen, and M. Linjama, eds. The fifth workshop on
digital fluid power, DFP’12, 24–25 October, 2012. Tampere,
Finland, 133–152.
Scheidl, R., Garstenauer, M., and Manhartsgruber, B., 2000.
Switching type control of hydraulic drives – a promising
perspective for advanced actuation in agricultural machinery.
SAE-Technical Paper Series 2000-01-2559, Society of
Automotive Engineers.
Scheidl, R. and Hametner, G., 2003. The role of resonance in
elementary hydraulic switching control. Proceedings of the
Institution of Mechanical Engineers, Part I: Journal of Systems
and Control Engineering, 217, 469–480.
Scheidl, R., Lukachev, E., and Haas, R., 2014. A hydraulic
switching control concept exploiting a hydraulic low pass
filter. In: L.J. De Vin, and J. Solis, eds. The 14th mechatronics
forum international conference, 16–18 June,
Karlstad, Sweden.
Scheidl, R. and Kogler, H., 2013. Hydraulische Schaltverfahren:
Stand der Technik und Herausforderungen. Ölhydraulik
und Pneumatik, 57 (2), 6–18.
Suzuki, K., 1991. Improving Zielke’s method of simulating frequency-
dependent friction in laminar pipe flow. Journal of
Fluids Engineering, 113, 569–573.
Viersma, T.J., 1980. Analysis, synthesis and design of hydraulic
servosystems and pipelines (Studies in Mechanical Engineering).
Amsterdam: Elsevier.
White, P.R.S., et al., July-Sept 1984. The development of novel
linear air dampers for use in sea-wave energy converter
model tests. Transactions of the Institute of Measurement
and Control, 6 (4), 182–188.
Zielke, W., 1968. Frequency-dependent friction in transient pipe
flow. ASME Journal of Basic Engineering, 90 (1),
–115.
