liu.seSearch for publications in DiVA
Change search
Refine search result
1 - 6 of 6
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Axin, Mikael
    et al.
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, The Institute of Technology.
    Eriksson, Björn
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, The Institute of Technology.
    Krus, Petter
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, The Institute of Technology.
    Flow versus pressure control of pumps in mobile hydraulic systems2014In: Proceedings of the Institution of mechanical engineers. Part I, journal of systems and control engineering, ISSN 0959-6518, E-ISSN 2041-3041, Vol. 228, no 4, p. 245-256Article in journal (Refereed)
    Abstract [en]

    This work studies an innovative working hydraulic system design for mobile applications, referred to as flow control. The fundamental difference compared to load-sensing systems is that the pump is controlled based on the operator’s command signals rather than feedback signals from the loads. This control approach enables higher energy efficiency since the pressure difference between pump and load is given by the system resistance rather than a prescribed pump pressure margin. Furthermore, load-sensing systems suffer from poor dynamic characteristics since the pump is operated in a closed-loop control mode. This might result in an oscillatory behaviour. Flow control systems have no stability issues attached to the load pressure feedback since there is none. This allows the pump to be designed to meet the response requirements without considering system stability. Pressure compensators are key components in flow control systems. This study addresses the flow matching problem which occurs when using traditional compensators in combination with a flow-controlled pump. Flow sharing pressure compensators solve this problem since the pump flow will be distributed between all active functions. Simulation results and measurements on a wheel loader application demonstrate the energy-saving potentials and the dynamic improvements for the flow control system.

  • 2.
    Edström, Krister
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Glad, Torkel
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Algorithmic, Physically based Mode Initialization when Simulating Hybrid Systems2002In: Proceedings of the Institution of mechanical engineers. Part I, journal of systems and control engineering, ISSN 0959-6518, E-ISSN 2041-3041, Vol. 216, no I1, p. 65-72Article in journal (Refereed)
    Abstract [en]

    In the simulation of hybrid systems, discontinuities can appear at mode changes. An algorithm is presented that gives initial values for the continuous state variables in a new mode. The algorithm is based on a switched bond graph representation of the system, and it handles discontinuities introduced by a changed number of state variables at a mode change. The algorithm is obtained by integrating the bond graph relations over the mode change and assuming that the physical variables are bounded. This gives a relation between the variables before and after the mode change. It is proved here that the equations for the new initial conditions are solvable. The algorithm is related to a singular perturbation theory by replacing the discontinuity by a fast continuous change. The action is considered of a single switch and the corresponding continuous change, tuned by a single parameter. By letting this parameter tend to zero, the same initial state values are achieved as those derived by the presented algorithm. The algorithm is also related to physical principles such as charge conservation.

  • 3.
    Eriksson, Björn
    et al.
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Palmberg, Jan-Ove
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Individual Metering Fluid Power Systems: Challenges and Opportunities2011In: Proceedings of the Institution of mechanical engineers. Part I, journal of systems and control engineering, ISSN 0959-6518, E-ISSN 2041-3041, Vol. 225, no 12, p. 196-211Article in journal (Refereed)
    Abstract [en]

    A review of recent and current research on individual metering fluid power systems is presented. An overview of different systems and their pros and cons is given. General challenges related to independent metering fluid power systems are discussed. The major choices in the design of these systems are the hardware layout and the control strategy. The evolution of existing independent metering fluid power systems from the 1970s until the present day is also presented.

  • 4.
    Johansson, Andreas
    et al.
    Parker Hannifin, Sweden.
    Ölvander, Johan
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Palmberg, Jan-Ove
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Experimental verification of cross-angle for noise reduction in hydraulic piston pumps2007In: Proceedings of the Institution of mechanical engineers. Part I, journal of systems and control engineering, ISSN 0959-6518, E-ISSN 2041-3041, Vol. 221, no 3, p. 321-330Article in journal (Refereed)
    Abstract [en]

    One of the most important drawbacks with hydraulic systems is noise and vibration, which mainly originate from the hydrostatic pump. A great number of noise-reducing design features have been developed, but they are all, to a greater or lesser extent, sensitive to variations in operational conditions. The present paper is concerned with optimal design and experimental verification of the cross-angle in an axial piston pump. The cross-angle is a small fixed incline of the swash plate in the direction that is perpendicular to the traditional displacement direction. It enables effective noise reduction throughout the whole range of displacement angles.

    Simulation-based optimization is used to design a pump with optimal cross-angle and a matching valve plate. The design is manufactured and experimentally evaluated. Source flow measurements using the two-microphone method show good agreement between simulation and experiments, which verifies the applicability of the simulation model used. The benefits from using the cross-angle are then verified by comparing it with a pump with a traditional swash plate design, i.e. without the cross-angle. Both source flow measurements and sound level measurements in an anechoic chamber show good improvements from using the cross-angle.

  • 5.
    Liu, Bin
    et al.
    ABB Corp Research Centre, Sweden.
    Sjöberg, Johan
    Linköping University, Department of Electrical Engineering. Linköping University, Faculty of Science & Engineering.
    Laiho, Antti
    ABB, Finland.
    Optimization-based radial active magnetic bearing controller design and verification for flexible rotors2016In: Proceedings of the Institution of mechanical engineers. Part I, journal of systems and control engineering, ISSN 0959-6518, E-ISSN 2041-3041, Vol. 230, no 4, p. 339-351Article in journal (Refereed)
    Abstract [en]

    Engineering costs, especially cost for controller design, are substantial and obstruct active magnetic bearings for broader industrial applications. An optimization-based active magnetic bearing controller design method is developed to solve this problem. Optimization criteria are selected to describe active magnetic bearing practical performance. Controller components are chosen considering that the parameters can be manually interpreted and modified on-site for commissioning. A multi-objective optimization toolbox can be used to tune the controller parameters automatically by minimizing the optimization criteria. The method has been verified within a controller design process for an active magnetic bearing levitated machine. With this method, engineering effort for controller design can be reduced significantly.

  • 6.
    Pohl, Jochen
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Fluid and Mechanical Engineering Systems .
    Sethson, Magnus
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Fluid and Mechanical Engineering Systems .
    Krus, Petter
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Machine Design .
    Palmberg, Jan-Ove
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Fluid and Mechanical Engineering Systems .
    Modelling and validation of a fast switching valve intended for combustion engine valve trains2002In: Proceedings of the Institution of mechanical engineers. Part I, journal of systems and control engineering, ISSN 0959-6518, E-ISSN 2041-3041, Vol. 216, no 2, p. 105-116Article in journal (Refereed)
    Abstract [en]

    In recent years much research has been done in the area of variable-valve actuation in order to improve the efficiency of combustion engines. Currently, a number of different concepts for variable-valve actuation are under development or at a prototype stage. Hydraulic actuation has been an obvious candidate, but the lack of sufficiently fast switching valves with appropriate flowrates has been the major shortcoming. Design of such highly dynamic systems requires accurate models of the actual included components. In this paper a model of a fast 2/2 switching valve is presented, where both the magnetic path as well as the spool assembly are modelled. The model presented here is primarily aimed at system simulations, therefore it has to be kept simple with the number of parameters low. Some of the parameters are often hard to obtain, especially when it comes to magnetic material properties. In this study, an optimization strategy has been utilized in order to parameterize the model against measured data. However, even for major deviations from the operational point used for the model adaptation, the model predicts the valve response sufficiently accurately.

1 - 6 of 6
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf