As a partner in the MARPOWER project, the Technical University of Denmark (DTU, Danmarks Tekniske Universitet) contributes its expertise in magnetic bearing technologies for advanced maritime energy systems. DTU’s research focuses on innovations that enable high-speed rotating machinery to operate safely, quietly, and efficiently even on a moving ship.
The MARPOWER project aims to advance the decarbonization of maritime transport by developing a novel flexible energy conversion system. The MARPOWER Energy Conversion System (MECS) is designed to use a wide range of sustainable fuels such as green methane, green methanol, hydrogen, and ammonia, with no or only minor modifications to the combustion system.
To achieve this level of performance and fuel flexibility, the MARPOWER project relies on cutting-edge technologies such as active magnetic bearings (AMBs). Magnetic bearings use electromagnetic fields instead of oil or mechanical contact to keep the rotor suspended in air. This non-contact design allows machines to spin at very high speeds with minimal energy loss and no mechanical wear. Within the project, this technology is essential for achieving reliable performance under the continuous motion and vibration experienced at sea.
AMBs play a central role in the MECS. By eliminating friction and mechanical contact, they improve system performance, reduce maintenance, and extend the lifespan of critical components. Their active control system adjusts magnetic forces in real time to keep the rotor centred even as the vessel rolls or pitches. This ensures stable operation in demanding marine environments and helps meet the MARPOWER project’s performance targets for efficiency, low noise, and durability.
The absence of mechanical contact also allows for higher rotational speeds and more compact, lightweight designs, which are crucial for increasing power density in shipboard applications. Together, these features make AMBs a cornerstone of the MARPOWER project’s mission to deliver a flexible, zero-emission energy conversion system capable of running on sustainable fuels.
Simulating the motion of the sea in the lab
To validate these technologies under realistic conditions, DTU has developed a small-scale magnetic bearing test rig mounted on a pneumatically actuated moving platform. The setup reproduces the rolling and pitching motions of a ship, allowing researchers to study how the rotor behaves during dynamic operation.
The system includes active and passive magnetic bearings to control and support the rotor, backup ball bearings for safety, high-precision sensors to measure displacement and vibration, and a 5.5 kW electric motor capable of driving the rotor at speeds up to 36,000 rpm. This controlled environment makes it possible to observe how the system responds to motion, contact events, and re-stabilization.
In collaboration with the project coordinator, LUT University, DTU has carried out a series of experiments to examine how a magnetically levitated vertical rotor performs on a moving base. When the platform tilts to reproduce ship motion, the tests show that the rotor occasionally makes brief contact with the backup, or touchdown, bearings. Each event lasts only a fraction of a second and is followed by rapid recovery, as the control system stabilizes the rotor.
These experiments confirm that the AMB control system can quickly restore stability after disturbances, preventing mechanical damage and maintaining continuous operation. The data also provide valuable insight into how contact forces develop during such events, helping to refine bearing design and control strategies for future marine energy systems.
DTU and LUT researchers are now using this experimental data to develop models that simulate friction, thermal effects, and contact dynamics. These models deepen understanding of system behaviour and guide the design of next-generation AMB-supported turbines and generators.
DTU’s contribution to MARPOWER’s objectives
Professor Ilmar Ferreira Santos, who leads the MARPOWER team at the Mechatronics & Tribology Lab of the Department of Civil and Mechanical Engineering (DTU Construct), highlighted the importance of the moving platform experiments for advancing the project’s research goals: “These experiments have given us valuable insight into how magnetic bearings behave under realistic maritime motion. We conduct experimental tests on a small-scale test rig, but similitude theory – based on geometric, kinematic, and dynamic similarities – is being carefully investigated and employed to shed light on the scalability of the results in terms of rotordynamics. This means, among others, that the relative forces on the real turbine levitated by active magnetic bearings will be comparable to the relative forces on the actual small-scale prototype under full levitation as well as under severe contact with backup bearings. The results are helping us refine our control strategies and design more resilient systems, directly supporting MARPOWER’s aim to develop reliable, high-efficiency energy technologies for ships of the future”.
The DTU team involved in MARPOWER includes Bruno Rende, postdoc; August Strandfelt, research assistant; ongoing master’s students Mikkel Gerner Jerlach and Thais Peter Bredal Jørgensen; and former master’s students Johannes Lindgaard Lildholdt and Niels Christian Henriksen, all contributing to the design, modelling, similitude analysis, and testing of magnetic bearing systems within MARPOWER.
Towards a sustainable maritime future
Through the development and testing of magnetic bearing technologies, the Technical University of Denmark and the MARPOWER project are contributing to a new generation of maritime energy systems that combine efficiency, reliability, and environmental responsibility. By combining science and innovation, the MARPOWER project demonstrates how advanced engineering can support a cleaner and more sustainable future for global shipping.