This paper proposes a solar energy harvesting based modular battery balance system for electric vehicles. The proposed system is designed to charge the battery module with minimum SOC/voltage by solar power during charging and discharging. With the solar power input, the useful energy of the battery can be improved while vehicle driving. For vehicle charging, the charging energy from grid and total charging time can be reduced as well. Simulation analysis shows that for a 50Ah rated battery pack, the overall pure electric drive mileage can be improved by 22.9%, while consumed grid energy and total charging time can be reduced by 9.6% and 9.3% respectively. In addition, the battery life can be improved around 10%~11%. The prototype design and test of a 48V battery pack vehicle consisting of four 12V battery modules are carried out. The experimental results validate that the system has good modular balance performance for the 100Ah battery modules with 5~7A charging current from solar power, and the overall usable battery energy has been increased.
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An inductively powered line-mounted time-synchronized micro point-on-wave recorder
The distribution system is an integral part of the electric power system, but not much is known about how it behaves in real-time. To address this knowledge gap, a low-cost, time-synchronized, micro point-on-wave recorder is designed, built, and characterized in this paper. The inductively powered recorder operates wirelessly by using the current flowing through a typical distribution conductor. The recorder is designed to be small, lightweight, and is intended to be installed directly on the power line. To validate the performance of this recorder, tests of measurement accuracy, electric current requirements, and susceptibility to electromagnetic interference from both steady-state and arc-induced sources are performed. The results indicate that the proposed recorder satisfies both the technical as well as the economical constraints required for bulk deployment in an actual distribution network.
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- Award ID(s):
- 1934766
- PAR ID:
- 10290371
- Date Published:
- Journal Name:
- IEEE Power Energy Society General Meeting
- ISSN:
- 1944-9933
- Page Range / eLocation ID:
- 1-5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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