Christoph Gradl, Ivo Kovacic, Rudolf Scheidl,
"Simulation and Experimental Investigations of a Hydraulic Stepper Drive"
: Proceedings of the ASME/BATH 2015 Symposium on Fluid Power & Motion Control (FPMC2015), October 12-14, 2015, Chicago, Illinois, USA, Vol. accepted for publication, 10-2015
Simulation and Experimental Investigations of a Hydraulic Stepper Drive
Sprache des Titels:
Proceedings of the ASME/BATH 2015 Symposium on Fluid Power & Motion Control (FPMC2015), October 12-14, 2015, Chicago, Illinois, USA
This paper presents simulation and experimental results of an energy saving hydraulic stepper drive prototype. Different concepts, advantages and the mechanical design of such kind of stepper drive were discussed in a previous publication. The excellent efficiency, the possibility of energy recuperation, and the control by switching and check valves only, may help to open new applications for hydraulic drives. Also the flow rate can be controlled rather directly by adjusting the switching frequency. This characteristic makes the sensorless position and speed control relatively easy.
The drive is realized by a hydraulic cylinder piston unit which displaces a defined fluid quantum by the limited forward stroke of the piston controlled by a fast switching valve. This end to end motion of the piston in its cylinder generates a precise, incremental motion of an additional load cylinder; this enables a sensorless position control. Energy saving is achieved by storing the pressure surplus intermediately in the kinetic energy of the piston to displace a part of the fluid quantum without hydraulic energy from the supply line.