Yosra Attia

This study investigates the usage of Gallium Nitride (GaN) and Silicon Carbide (SiC), in DC/DC converters; as an alternative to the conventional Si Converters exploiting their high switching capabilities with low losses. This work focuses mainly on the converter used in Electric vehicles for the purposes of charging the battery. A complete model has been developed and a comparison between using SiC and GaN has been performed to determine the viability of using each one in terms of temperature and converter losses. A case study of Nissan Leaf EV is being adopted as a proof of concept and a prototype for it was built in the lab. The experimental results regarding each component and their relationship with the simulation results. It was obvious that the simulation results match perfectly the experimental ones on a system-level basis.

This paper introduces a novel engineering feasibility study for developing a future hybrid metro system, for the first time in Canada, that is of extremely low cost and independent of the utility grid. This system will eliminate the need of the rail cars to rely on the track substations and consequently the utility grid. This paper is based on the load profiles provided by Bombardier Transportation for its advanced rapid transit train running in Vancouver, BC, Canada. Simulation was performed for propulsion with and without auxiliary power with the assumption of an average power of 40 kW. To size the system for the worst case scenario, the regeneration power will not be taken into account in case the propulsion cuts off during regenerative braking. The subsystem modules described in the model are listed for reference purposes. The hydrogen consumption and storage are also calculated for each case with the tank options listed for each energy storage option. Furthermore, an analysis platform is being provided for a sound design of a hybrid metro car for the first time in North America. This systematic modular approach can be easily applied to any transit system worldwide. A successful design for a fuel cell hybrid train is given, which is fully independent on the electricity from the grid. The elimination of the wayside substations system, which is 90% of the cost of the transit system, presents huge initial and running cost savings and makes the rail car ridership very inexpensive.

This paper introduces a unique quantified study about using low-losses fast-switching wide bandgap (WBG) devices, i.e., gallium nitride (GaN) and silicon carbide (SiC), over traditional Silicon (Si) devices in the switching of dc/dc converters, focusing on electric vehicles’ (EVs) machine drive and battery charger. A detailed model of the power train of a Nissan Leaf was developed in PSIM software, with WBG semiconductors’ capability. The model was simulated one time using GaN semiconductors and another time using SiC devices. Simulation results are quantified and a comparison between different semiconductors in terms of total losses and efficiency is presented. The developed PSIM model can also be extended to other EVs like Chevy Volt. A proof of concept prototype for a Nissan Leaf dc/dc converter was built in the laboratory and results were collected. Componentwise experimental results are presented and their correlation with simulation findings is demonstrated. In addition, exper...