Evgeny Lukachev, Rudolf Scheidl,
"Hydraulic switching type position control of a large cylinder drive"
, in GFPS: Proceedings of the Global Fluid Power Society PhD Symposium (GFPS2018), Samara, Russia, 7-2018, ISBN: 978-1-5386-4785-1
Original Titel:
Hydraulic switching type position control of a large cylinder drive
Sprache des Titels:
Englisch
Original Buchtitel:
Proceedings of the Global Fluid Power Society PhD Symposium (GFPS2018), Samara, Russia
Original Kurzfassung:
Hydraulic drives are well known for their
outstanding force and power density and drive stiffness. They are
indispensable when heavy load applications have to meet strict
demands on fast response and high precision. A typical example
is the steel rolling mill where the majority of material forming
operations is hydraulically actuated. Before long the only
available control unit for these drives were servo valves. The
latter have numerous disadvantages intrinsic to their concept and
design: extreme sensitivity to oil cleanliness, vast leakages and
high prices. The resulting high maintenance and installation
costs, low efficiency, and reliability motivate to find a
replacement for the servo valves, which do not have these
disadvantages and provide similar or better performance. One of
the possible solutions is employing one of the many digital
hydraulic concepts, in this paper an elementary switching
concept using fast switching valves. Basically, such valves do
much better than the servos in terms of robustness to oil
contamination and leakage, and they have also a reasonable
potential for significantly lower price provided sufficient
production quantities are reached. The main challenges of
switching control are oscillations excited by fast switching and
cavitation caused by fast valve closure. Oscillations have negative
influence on the tracking performance and can be a source of
unwanted noise. The problem is likely to be worsened by a
transmission line between the cylinder and the valve control unit
if the latter has to be placed some distance away from the
cylinder or if the cylinder wall is thick and the connecting
channel length cannot be neglected even by a directly mounted
valve block...
Forschungs-