0

Full Content is available to subscribers

Subscribe/Learn More  >

On/Off Valve Based Position Control of a Hydraulic Cylinder

[+] Author Affiliations
Michael B. Rannow, Perry Y. Li

University of Minnesota, Minneapolis, MN

Paper No. IMECE2007-42590, pp. 141-149; 9 pages
doi:10.1115/IMECE2007-42590
From:
  • ASME 2007 International Mechanical Engineering Congress and Exposition
  • Volume 4: Design, Analysis, Control and Diagnosis of Fluid Power Systems
  • Seattle, Washington, USA, November 11–15, 2007
  • Conference Sponsors: ASME
  • ISBN: 0-7918-4298-3 | eISBN: 0-7918-3812-9
  • Copyright © 2007 by ASME

abstract

A method of precisely controlling the position of a hydraulic actuator using an on/off valve is developed. Since valves exhibit little power loss when they are fully open or fully closed, the proposed system is more efficient than throttling valve control and can achieve flow variation without the expense or bulk of a variable displacement pump. Mating a pulse-width-modulated (PWMed) on/off valve with a fixed displacement pump and a smoothing accumulator creates a software enabled variable displacement pump. A drawback of using digital valve control for hydraulic systems is that the relatively low speed of the currently available switching valves results in a significant ripple in the pressure and flow rate. We propose a solution to this problem by using a throttling valve to shield the actuator from the ripple in the output. This creates an effective load sensing system with the throttling valve used only to provide a small known pressure drop between the supply and the load. This approach is significantly more efficient than the conventional technique of using throttling to vary the full flow. This paper presents an averaged model of the system, a nonlinear controller to achieve position control of an actuator and a simulation based study of the effectiveness of the controller.

Copyright © 2007 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In