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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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A Localized and Packetized Approach to Distributed Power Inverter Management
Abstract—Local management of solar photovoltaic and battery inverters is seen as a means to mitigate many grid issues that can result from large penetrations of distributed and variable solar energy. This work demonstrates through simulation how local inverter operation can fit within an operational paradigm referred to as packetized energy management. In particular, the power factor at which energy packets are injected in to the grid from a distributed set of energy resources (i.e., batteries) are adjusted in discrete steps over the range of operation. Unlike approaches where a device’s power factor is adapted continuously over time, the discrete-time and asynchronous nature of the investigated approach avoids potential system oscillations. We present simulation results for a feeder line consisting of 100 battery systems comparing our distributed, locally-controlled approach to one centrally determined and controlled.
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- Award ID(s):
- 1722008
- PAR ID:
- 10084299
- Date Published:
- Journal Name:
- Proc. of the 2019 IEEE Power and Energy Society General Meeting
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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