Public defence in Industrial Electronics and Electric Drives, M.Sc. Arbër Haxhiu

M.Sc. Arbër Haxhiu will defend the thesis "The Variable DC Approach for Improved Powertrain Energy Efficiency in Fuel Cell-Fed Marine Vessels" on 9 December 2022 at 12 (EET) in Aalto University School of Electrical Engineering, Department of Electrical Engineering and Automation, in lecture hall AS1, Maarintie 8, Espoo.

Opponent: Prof. Frede Blaabjerg, Aalborg University, Denmark
Custos: Prof. Jorma Kyyrä, Aalto University School of Electrical Engineering, Department of Electrical Engineering and Automation

Thesis available for public display 10 days prior to the defence at: https://aaltodoc.aalto.fi/doc_public/eonly/riiputus/
Doctoral theses in the School of Electrical Engineering: https://aaltodoc.aalto.fi/handle/123456789/53

Public defence announcement:

The Maritime industry is undergoing a significant technological transition from environmentally polluting fossil-based fuels used for onboard power generation towards less harmful fuels. Green hydrogen is considered a great means to achieve zero-emission operation where fuel cells are used to convert hydrogen energy to electrical energy which is used to meet the power requirements of a ship. Cost and energy efficient utilization of hydrogen fuel cells on board ships can be achieved using advanced electric integration concepts. However, due to the past dominance of combustion engine-based power systems, existing integration concepts have also been primarily optimized for engine-based power generation, and thus are typically less optimized for fuel cell powered vessels.

This thesis reviews and analyses existing state-of-art electric power integration concepts for fuel cell powered marine vessels and proposes a new electric integration concept for future fuel cell powered vessels which operate either together or without electric energy storage devices such as batteries. The proposed concept is based on variable operation of DC power distribution voltage as a function generated fuel cell power. The DC voltage variation enables switching-free operation of fuel cell power converters resulting in meaningful improvements in ship's fuel consumption, and thus can significantly reduce the operating costs of a ship operator. This thesis develops hardware and control methods associated to the proposed electric integration concept and presents operating results of a system utilizing the said concept. The methods are verified using a marine power system hardware-in-loop test setup developed for the purpose of electric system testing.

Contact information of doctoral candidate: