Ehydraulics

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The aim of the project is to promote the electrification of working machines. Neither the hydraulic systems nor the pumps are currently optimised for use with an electrical primary source of energy.

Hydraulic systems can work with high efficiency, and the project is eager to preserve this. In combination with electric power supply to the pump, in particular in mobile applications, it is important that the combined unit, known as an “E-pump”, unites the advantages of electricity and hydraulic systems. This project is based on the suggestion to create an integrated component in which an electric motor and power-supply electronics are combined with a suitable hydraulic pump concept. The combined unit will have higher power density and efficiency, with a lower noise level.

Current hydraulic systems do not exploit the potential of electrical systems to provide varying rates of revolution, nor their ability to distribute and recycle the available energy. If these benefits can be used, it will give better system efficiency, which in turn means that the required battery capacity in the vehicle is lower.

Electrohydraulic

Many different electrohydraulic systems have been proposed, but none of them has taken a comprehensive view of how, where and when the various system solutions are to be used to achieve optimal functionality in combination with best energy efficiency. Considering the needs of many OEMs within same project will result in a broader and deeper understanding of electrohydraulic systems and their potential to reduce energy consumption. It will be possible for the project to draw high-quality conclusions by validation of theoretical solutions in both simulated and laboratory environments.

E-pump

A satisfactory solution for an integrated solution with an electric motor and a hydraulic pump/motor has not been presented, but the need for new solutions for E-pumps for electrically operated mobile machine has become clear. The proposed pump has good noise properties, in combination with high efficiency and compactness. In addition, it has unique possibilities for integration with an electric motor. The design of the pump allows many different E-pump solutions to be created for different systems and operating conditions, and one, two or four-quadrant pumps can be built. This will require cross-functional development that involves discussion with OEMs to determine their requirements and expectations.

The result of the E-pump development will benefit all applications that use hydraulic systems, such as manufacturing facilities, forestry machines, trucks and aircraft.

Hypotheses

1

The specification of requirementsfor the mobile hydraulic system will change when the primary source of powerchanges from combustion engines to electric motors.

2

It will be possible to integratethe hydraulic pump/motor with the electric motor to create a more compact andefficient unit adapted for mobile applications.

3

The smart integration andco-optimisation of the hydraulic system and the electrohydraulic pump will leadto improvements in both system components.

Brief facts about the project

Funding

The Swedish Energy Agency – FFI Energy and Environment

FFI, a strategic initiative in vehicle research and innovation, is a collaboration between the government (VINNOVA, the Swedish Transport Administration, and the Swedish Energy Agency) and the motor industry (Scania CV, AB Volvo, Volvo Personvagnar and FKG). It provides collaborative funding for research, innovation and development with a focus in two areas: climate & environment, and safety. The initiative has an annual budget of around SEK 1 billion, half of which is public funding.

Project partners

Epiroc Rock Drills AB
Volvo Construction Equipment
Volvo personvagnar

Schedule

April 2020-March 2023

Electrohydraulic is to be of three years’ duration and is one component of the FFI, a national initiative in vehicle research and innovation.

Contacts

Project Leader

Researcher

viktor.larsson@liu.se

PhD student

News

A hydraulic pump powered by electricity

Fossil-free applies also to heavy mobile working machines. Liselott Ericson, Flumes, has received SEK 11.6 million to collaborate with industry in developing technology that uses a hydraulic pump in electrically operated working vehicles.

Fluid Power

LiU has the largest university laboratory for fluid power systems in Sweden. We aim to develop smarter and more energy efficient hydraulic systems, components and methods to reduce energy losses.

Organisation

Fluid and Mechatronic Systems (FLUMES)

The division Fluid and Mechatronic Systems belongs to Department of Management and Engineering and carries out research and education in fluid power systems and aeronautics.

Department of Management and Engineering (IEI)

The Department of Management and Engineering (IEI) strengthens and develops tomorrow’s industry, business world and society by ground-breaking research, education and innovation.

Studenthuset on Campus Valla in Linköping

About LiU

Linköping University, LiU, offers innovative education and boundary-crossing research. The students are among the most desirable in the labour market and international rankings consistently place LiU as a leading global university.