Introduction
High power transportations account for a great amount of greenhouse gas. For example, maritime transportation is responsible for 3% of global greenhouse gas emissions; rail transport is responsible for 4%. To reduce the emission, high power transportation sectors are going through electrification with the utilization of clean energy sources. Fuel cell is a promising sustainable energy source for future high power transportation due to its lower or zero greenhouse-gas emission, less noise, and high efficiency features compared to convention generators. However, a main shortcoming of fuel cell is its unregulated low-output voltage characteristics that is significantly impacted by loading profile. Thus, a power electronic converter plays an essential role to boost and regulate the output voltage of fuel cell to a designed value under different loading profiles. Moreover, the high frequency current ripple in the system may degrade lifespan of fuel cell, and thus the power electronic converter is required to mitigate the high frequency current ripple. Also, the power electronic converter is required to stabilize the system under the changing load profiles of high power transportations.

Objectives
This project is conducted with ABB. This project is to design power electronic converter with associate control strategies for the integration of fuel cells in high power transportation with optimized performance. Specifically, the converter will achieve high voltage gain with accurate output voltage regulation, suppressed input current ripple, and guaranteed stability under changing load profiles. Tasks include:

• Literature review of power converter topologies and associated control strategies for fuel cell integration, and select 3 candidates based on requirements.
• Build simulation models for the selected converter.
• Evaluate and down-select the topology. New topologies will also be explored to further enhance the performance.
• Advanced control strategies will be further developed to enhance the performance of the selected/designed topology.
• Write the master thesis.

Requirements on students:
We are looking for one master thesis student (30 hp) in the field of electric power systems with:
• Good knowledge of power electronics, especially in modeling and control of power electronic converters
• Strong MATLAB/Simulink skill
• Good hardware skill

Contact persons and supervisors:
At ABB: Dr. Ahmed Abdelhakim ahmed.abdelhakim@se.abb.com
At KTH: Dr. Qianwen Xu qianwenx@kth.se