This paper deals with the issue of position tracking control of a clamp-cylinder for an injection moulding machine with electric-hydrostatic drives. In order to accommodate mismatches between the real plant and the model used for controller design, discrete-time sliding mode control is developed by combining a velocity feedforward loop. From tracking control experiments, it is shown that significant reduction in position tracking error is achieved through the use of a sliding mode control scheme. The effect of dry-cycle time on position tracking error is examined for the possibility of attaining a high-speed injection moulding machine.
HelduserS.‘Development trends in electrohydraulic drives and controls.’ In 6th International Fluid Power Conference (IFK), Dresden, Germany, 2008 vol. 2, pp. 29–64.
2.
HelbigA.Energieeffizientes elektrisch-hydrostatisches Antriebssystem am Beispiel der Kunststoff-Spritzgießmaschine Dissertation, TU Dresden, 2007.
3.
HelduserS.‘Electric-hydrostatic drive - an innovative energy-saving power and motion control system.’Proc. Instn Mech. Engrs, Part I: J. Systems and Control Engineering213 (1999): 427-437 DOI: 10.1243/0959651991540250.
4.
KazmeierB.Energieverbrausoptimierte Regelung eines elektrohydraulischen Linearantriebs kleiner Leistung mit drehzahlgeregeltem Elektromotor und Verstellpumpe Dissertation, Hamburg-Harburg, 1998.
5.
ChiangM. H.LeeL. W.TsaiJ. J.‘The concurrent implementation of high velocity control performance and high energy efficiency for hydraulic injection moulding machines.’Int. J. Advd Mf. Technol.23 (2004): 256–262
6.
LongQ.NeubertTh.‘Hochdynamische Lageregelung fuer Differenzialzylinder mit zwei drehzahlgeregelten Pumpen.’Hydraulik und Pneumatik44 (9). (2000).
7.
RühlickeI.Elektrohydraulische Antriebssysteme mit drehzahlveränderbarer Pumpe Dissertation, TU Dresden. 1997.
8.
RistićM.‘Conversant technology - new key aspects: development of variable-speed drives.’ In 6th International Fluid Power Conference (IFK), Dresden, Germany, 2008, vol. 2, pp. 93–108.
9.
ChoS. H.EdgeK. A.‘Adaptive sliding mode tracking control of hydraulic servosystems with unknown non-linear friction and modelling error.’Proc. Instn Mech. Engrs, Part I: J. Systems and Control Engineering214 (I4) (2000): 247-257 DOI: 10.1243/0959651001540618.
10.
LuckK.StrauchmannH.Auslegung 6gliedriger Doppelkniehebelmechanism für Schließeinheiten mit 100/50/25 Mp Schließkraft Abschlussbericht, TU Dresden, 1978.
11.
ChoS. H.‘Robust discrete time tracking control using sliding surfaces.’J. Mech. Sci. Technol.9 (1) (1995): 80–90
