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Low-RPM Torque Converter (LRTC)
Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Electrical Engineering, Electricity.
Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Electrical Engineering, Electricity.
Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Electrical Engineering, Electricity.
2021 (English)In: Energies, E-ISSN 1996-1073, Vol. 14, no 16, article id 5071Article in journal (Refereed) Published
Abstract [en]

The concept concerned in this paper is based on energy conversion of the ocean waves via rotational generators. The objective of this research is to develop a new type of slow-motion converter. The LRTC device consists of a drum that is connected via wire to a floating buoy. The drum is connected to rotary generators. The generators are heavily braked when the direction of movement changes (up/down); this is because the generators have been charged the maximum load in order to obtain maximum output power. For upcoming improvement, the generators should have some power storage as flywheel. In the future experiments, the torque converter can even be tuned to rotate in resonance with the incoming waves, strongly increasing power absorption. Constant force springs are applied for this purpose. The focus of this project is, therefore, a new generation of wave power device for utility-scale energy conversion offering a cost of energy that can compete with established energy resources.

Place, publisher, year, edition, pages
MDPI AG MDPI, 2021. Vol. 14, no 16, article id 5071
Keywords [en]
wave energy conversion, torque converter, resonance frequency
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering Energy Engineering
Identifiers
URN: urn:nbn:se:uu:diva-455502DOI: 10.3390/en14165071ISI: 000690643600001OAI: oai:DiVA.org:uu-455502DiVA, id: diva2:1601327
Funder
StandUpAvailable from: 2021-10-07 Created: 2021-10-07 Last updated: 2024-12-10Bibliographically approved
In thesis
1. Industrial robot as main equipment for testing and production of Wave Energy Converters
Open this publication in new window or tab >>Industrial robot as main equipment for testing and production of Wave Energy Converters
2025 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Since 2001, research and development on the conversion of ocean wave energy into electricity has been conducted at the Division of Electricity at Uppsala University. Different Wave Energy Converter (WEC) technologies has been developed, such as the point-absorber linear Uppsala University WEC (UU-WEC) and the Low-RPM Torque Converter WEC (LRTC-WEC). 

This thesis focuses primarily on the development of a robotized dry test rig, to facilitate assessment of different WEC technologies in house. An existing industrial six degrees of freedom robot system is used to emulate buoy movement on the sea surface, with regard to the impact of hydrodynamic forces in real time. Two different methods for integrating a hydrodynamic model to the robot controller are presented: the force control and the position control methods. Both methods are evaluated and validated across various regular and irregular wave climates, as well as for different theoretical buoy shapes.  

The secondary focus in this thesis is the development of robotized production methods for the UU-WEC. The surface mounting of Neodymium Iron Boron (Nd2Fe14B) magnets and the cutting of rubber discs are investigated, resulting in viable solutions that include development and validation of robot tooling and robot cell proposals. 

A smaller segment of the thesis examines the use of robotics in teaching a course for bachelor engineering students. At the outbreak of the COVID-19 pandemic a challenging task was imposed: a swift shift to online distant education. A major task was to replace physical lab exercises with video recordings, detailed instructions and simulated laboratory environments. The results indicated that the upgraded online education successfully meet the course objectives.

The final part of the thesis investigates the use of WECs for powering a desalination plant. Desalination presents a viable solution for islands or coastal regions deficient in freshwater resources, but is also an energy intensive process. Practical experiment evaluated the possibility of utilizing the UU-WEC as power source for desalination plants.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2025. p. 78
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 2485
Keywords
Dry test rig, Industrial robotics, Manufacturing automation, Large-scale production, Linear generator, Wave energy converter, Engineering education, Desalination
National Category
Robotics and automation Other Electrical Engineering, Electronic Engineering, Information Engineering Communication Systems Control Engineering
Research subject
Engineering Science with specialization in Science of Electricity; Engineering Science with specialization in Electronics; Engineering science with specialization in Applied Mechanics; Engineering Science with specialization in industrial engineering and management; Electrical Engineering with specialization in Automatic Control; Engineering Science with specialization in industrial engineering and management
Identifiers
urn:nbn:se:uu:diva-544285 (URN)978-91-513-2337-4 (ISBN)
Public defence
2025-02-10, Polhem, Lägerhyddsvägen 1, 75237 Uppsala, Uppsala, 09:15 (English)
Opponent
Supervisors
Available from: 2025-01-17 Created: 2024-12-10 Last updated: 2025-02-05

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fulltext(7688 kB)475 downloads
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Savin, AndrejSalar, DanaHultman, Erik

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