| dc.description.abstract | Promoting green energy in mobile applications, we developed energy management systems of architectural parallelism for a semi-active Direct Methanol Fuel Cell (DMFC) power station of extended life time for Internet of Things (IoT) applications in the field, and, also, for highly energy efficient battery hot swap technology for electric buses and power battery charging and exchange stations. Both of the applications realize the safety backup parallelism in the system for their fault tolerance.
For in field IoT applications, the conventional active DMFC with complexity optimized for the best electro chemical efficiency was simplified and optimized into the semi-active module for better production yield, easier assembly, and parallel operations. New battery management system were developed to coordinate the operation of the modules in parallel to scale up power capacity, to enhance power generation stability and its environmental endurance. The prototype survived 3600 hours of continuous outdoor tests throughout a winter and a summer while maintaining an average power output of 3.3W with a maximum 12W of transient load bearing capacity, complying to its design specifications.
On the other hand, to increase power capability, intelligent mobile battery packs with new integrated network capable battery management system were developed to allow battery hot swap and convenient, safe, reliable, energy efficient operation in parallelism. In the network of the plugged-in battery packs, the emerged primary pack coordinates the packs, through their control network, the mounting of the packs′ electric bus onto the common power bus directly and safely without voltage converters. Meanwhile, all other packs are the minors synchronizing to the whole network control status and getting ready to assume the primary role in case of any plug-in change and individual pack failure so that system is fault tolerant. The reliability of hot swap was verified through the tests of sequential plug-ins and random exchanges of battery packs. Our energy output efficiency is equivalent to a system of batteries connected together through voltage converters of efficiency as high as 99.2%. | en_US |