A novel hydromechanical hybrid motion system for construction machines


  • Karl Pettersson Driveline Systems, Volvo Construction Equipment, Eskilstuna, Sweden
  • Kim Heybroek Emerging Technologies, Volvo Construction Equipment, Eskilstuna, Sweden
  • Petter Krus Department of Management and Engineering, Linköping University, Linköping, Sweden http://orcid.org/0000-0002-2315-0680




Hydraulic hybrid, powersplit, secondary control, wheel loader


This paper deals with a novel type of hybrid motion system for construction machines based on a common pressure rail shared between a hydromechanical power-split transmission and secondary controlled work hydraulics. A construction machine with driveline and work functions is a complex coupled motion system and the design of an effective hybrid system needs to take both subsystems into account. Studies on energy efficient hybrid systems for construction machines have hitherto principally focused on one subsystem at a time – work hydraulics or driveline. The paper demonstrates a use case with a specific transmission concept proposal for a medium-sized wheel loader. The system is modelled and simulated using an optimal energy management strategy based on dynamic programming. The results show the benefits of a throttle-free bidirectional link between the machine’s subsystems and the energy storage, while taking advantage of the complex power flows of the power-split transmission.,


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Author Biographies

Karl Pettersson, Driveline Systems, Volvo Construction Equipment, Eskilstuna, Sweden

Karl Pettersson received his MSc degree in Mechanical Engineering from Linköping University, Sweden in 2009. He continued at the university as a PhD student in the division of Fluid and Mechatronic Systems. In 2013 he received his Licentiate degree within design automation of hydromechanical transmissions. He is now working at Volvo Construction Equipment with the focus on the design and control of hydromechanical hybrid drivelines.

Kim Heybroek, Emerging Technologies, Volvo Construction Equipment, Eskilstuna, Sweden

Kim Heybroek received his MSc degree from Linköping University, Sweden, in Mechanical Engineering in 2006. In 2008 he received his Licentiate Degree at the division of Fluid and Mechatronics Systems. In 2008 he was with Volvo Construction Equipment in Eskilstuna as a hydraulics design engineer mainly dealing with valve technologies for wheel loaders. In 2010 he joined the Emerging Technologies department, where he is currently working with electro-hydraulics and new machine concepts.

Petter Krus, Department of Management and Engineering, Linköping University, Linköping, Sweden

Petter Krus is a professor in Fluid and Mechatronic Systems at Linkoping University. Research interests are fluid power, mechanical and mechatronic systems technology, specifically focusing on system dynamics, control, system simulation, optimisation, system design and design automation. Applications are in aircraft design, road vehicles and construction machinery


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Original Article