skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: An optimization framework for workplace charging strategies

Publication Date:
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
OSTI Identifier:
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Transportation Research Part C: Emerging Technologies
Additional Journal Information:
Journal Volume: 52; Journal Issue: C; Related Information: CHORUS Timestamp: 2016-09-04 14:12:33; Journal ID: ISSN 0968-090X
Country of Publication:
United Kingdom

Citation Formats

Huang, Yongxi, and Zhou, Yan. An optimization framework for workplace charging strategies. United Kingdom: N. p., 2015. Web. doi:10.1016/j.trc.2015.01.022.
Huang, Yongxi, & Zhou, Yan. An optimization framework for workplace charging strategies. United Kingdom. doi:10.1016/j.trc.2015.01.022.
Huang, Yongxi, and Zhou, Yan. 2015. "An optimization framework for workplace charging strategies". United Kingdom. doi:10.1016/j.trc.2015.01.022.
title = {An optimization framework for workplace charging strategies},
author = {Huang, Yongxi and Zhou, Yan},
abstractNote = {},
doi = {10.1016/j.trc.2015.01.022},
journal = {Transportation Research Part C: Emerging Technologies},
number = C,
volume = 52,
place = {United Kingdom},
year = 2015,
month = 3

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.trc.2015.01.022

Citation Metrics:
Cited by: 7works
Citation information provided by
Web of Science

Save / Share:
  • The workplace charging (WPC) has been recently recognized as the most important secondary charging point next to residential charging for plug-in electric vehicles (PEVs). The current WPC practice is spontaneous and grants every PEV a designated charger, which may not be practical or economic when there are a large number of PEVs present at workplace. This study is the first research undertaken that develops an optimization framework for WPC strategies to satisfy all charging demand while explicitly addressing different eligible levels of charging technology and employees’ demographic distributions. The optimization model is to minimize the lifetime cost of equipment, installations,more » and operations, and is formulated as an integer program. We demonstrate the applicability of the model using numerical examples based on national average data. The results indicate that the proposed optimization model can reduce the total cost of running a WPC system by up to 70% compared to the current practice. The WPC strategies are sensitive to the time windows and installation costs, and dominated by the PEV population size. The WPC has also been identified as an alternative sustainable transportation program to the public transit subsidy programs for both economic and environmental advantages.« less
  • Real-time charging strategies, in the context of vehicle to grid (V2G) technology, are needed to enable the use of electric vehicle (EV) fleets batteries to provide ancillary services (AS). Here, we develop tools to manage charging and discharging in a fleet to track an Automatic Generation Control (AGC) signal when aggregated. We also propose a real-time controller that considers bidirectional charging efficiency and extend it to study the effect of looking ahead when implementing Model Predictive Control (MPC). Simulations show that the controller improves tracking error as compared with benchmark scheduling algorithms, as well as regulation capacity and battery cycling.
  • Structured mesh quality optimization methods are extended to optimization of unstructured triangular, quadrilateral, and mixed finite element meshes. N"ew interpretations of well-known nodally-bssed objective functions are made possible using matrices and matrix norms. The matrix perspective also suggests several new objective functions. Particularly significant is the interpretation of the Oddy metric and the Smoothness objective functions in terms of the condition number of the metric tensor and Jacobian matrix, respectively. Objective functions are grouped according to dimensionality to form weighted combinations. A simple unconstrained local optimum is computed using a modiiied N-ewton iteration. The optimization approach was implemented in themore » CUBIT mesh generation code and tested on several problems. Results were compared against several standard element-based quaIity measures to demonstrate that good mesh quality can be achieved with nodally-based objective functions.« less