Grant: Discovery Grants Program - Individual

Climate change has made the integration of renewable energy sources of paramount importance. Solar photovoltaic and wind are intermittent power sources that need to be supplemented with energy storage devices, the utility grid or by non fossil fuel based sources. A promising option is a hydrogen loop, consisting of a fuel cell powered from green hydrogen produced by water electrolyzers from renewable sources. It provides a means for long term energy storage, supporting batteries that perform well for short and medium terms. Hydrogen can be used in buildings and distribution systems as well as in electric vehicles. Actual battery technologies suffer from low energy densities, making hydrogen the most promising energy vector for all-electric aircrafts. The concept of smart grids concerns net-zero energy and resilient buildings and communities. There, the interfaces of energy resources need to be controlled with suitable energy management techniques in grid-connected, or stand-alone, electric power clusters. They should meet the load demand with good power quality while making sure that the energy resources operate with high efficiency and reliability with long lifetimes. For that an in-depth knowledge of the energy resources as well as fast acting, flexible and reliable power electronic interfaces are necessary. These require suitable topologies, semiconductor switches and control strategies. Electricity is supplied to the consumers in the AC form but multiple studies have demonstrated several benefits of DC distribution. Since the transition from AC to DC distribution systems is expected to occur gradually, power interfaces capable of operating connected to DC and AC buses are highly desirable. Wide band-gap semiconductors allow the switching of higher voltages and currents at higher frequencies with higher efficiency. However, other techniques for power topologies must be explored. Partial power converters (PPCs) only process a fraction of the power that flows between the input and the output, resulting in lower power losses, ratings and stresses on the semiconductors. Reconfigurable converters have been proposed for EV chargers that can be supplied from different sources, DC unipolar and bipolar, AC single-phase and three-phase. Non-redundant fault-tolerant topologies have also been conceived and are essential for some applications such as aerospace. This project investigates power converter topologies, modulation schemes and control strategies that can enhance the performance of decarbonized energy systems. They are tailored to the inherent characteristics of the energy resources to improve their efficiency, reliability and lifetime while providing support to the electric system. Power interfaces for hydrogen loops fed from renewable sources will be prioritized. Suitable multi-physics models for the control and fault detection of electrolyzers and fuel cells will be developed and used in stationary and transportation systems.