We develop hierarchical coordination frameworks to optimally manage active and reactive power dispatch of number of spatially distributed electric vehicles (EVs) incorporating distribution grid level constraints. The frameworks consist of detailed mathematical models, which can benefit the operation of both entities involved, i.e., the grid operations and EV charging. The first model comprises of a comprehensive optimal power flow model at the distribution grid level, while the second model represents detailed optimal EV charging with reactive power support to the grid. We demonstrate benefits of coordinated dispatch of active and reactive power from EVs using a 33-node distribution feeder with large number of EVs (more than 5,000). Case studies demonstrate that, in constrained distribution grids, coordinated charging reduces the average cost of EV charging if the charging takes place at non-unity power factor mode compared to unity power factor. Similarly, the results also demonstrate that distribution grids can accommodate charging of increased number of EVs if EV charging takes place at non-unity power factor mode compared to unity power factor.
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Microgrid Simulation Analysis of Critical Loads: Distribution Planning for Nonhomogenous EV Distributions
In the last several decades, public interest for electric vehicles (EVs) and research initiatives for smart AC and DC microgrids have increased substantially. Although EVs can yield benefits to their use, they also present new demand and new business models for a changing power grid. Some of the challenges include stochastic demand profiles from EVs, unplanned load growth by rapid EV adoption, and potential frequency (harmonics) and voltage disturbances due to uncoordinated charging. In order to properly account for any of these problems, an accurate and validated model for EV distributions in a power grid must be established. This model (or several models) may then be used for economic and technical analyses. This paper supplies insight into the impact that EVs play in effecting critical loads in a system, and develops a theoretical model to further support a hardware in-the-loop (HIL) real time simulation of modelling and analysis of a distribution feeder with distributed energy resources (DERs) and EVs based on existing data compiled.
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- NSF-PAR ID:
- 10294199
- Date Published:
- Journal Name:
- 2021 IEEE International Electric Machines & Drives Conference (IEMDC)
- Page Range / eLocation ID:
- 1 to 4
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/iemdc47953.2021.9449554
