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Salisbury, Shawn D.

Publications and source records attributed to Salisbury, Shawn D..

Concept Design of Active Shielding for Dynamic Wireless Charging of Light-duty EV

Dynamic wireless charging of electric vehicles is a flexible and state of the art charging technology with the potential capability of enabling fully automated in-motion charging. With charging power increasing to more than 100 kW for light duty vehicles, electromagnetic field (EMF) emission becomes a critical challenge. Due to the high costs of ferrite materials, this paper proposes an active shielding solution with multiple canceling coils installed on the ground side to supplement ferrite passive shielding to ensure electromagnetic safety. Two canceling coils are designed on two sides of the ground side coil. The canceling coils are small in size and 180 degree opposite in phase to the ground coil. Simulation and modeling shows that the canceling coils can reduce EMF emission from 37.2 µT to 18.2 µT at 0.8 m during 100 kW operation with only 2.5% of ground side current flowing in the canceling coils. These results have been preliminarily verified by inductance measurements and magnetic field measurement at 1.1 m distance without canceling coils. By further increasing the canceling coils’ currents to 4%, EMF emission can also be mitigated at 200 kW, although the canceling coils’ shape, position, and phase angle can be further optimized to improve the three-dimensional field distribution.

25 ENERGY STORAGE↗

Analysing the usage and evidencing the importance of fast chargers for the adoption of battery electric vehicles

An appropriate charging infrastructure is one of the key aspects needed to support the mass adoption of battery electric vehicles (BEVs), and it is suggested that publically available fast chargers could play a key role in this infrastructure. As fast charging is a relatively new technology, very little research is conducted on the topic using real world datasets, and it is of utmost importance to measure actual usage of this technology and provide evidence on its importance to properly inform infrastructure planning. 90,000 fast charge events collected from the first large-scale roll-outs and evaluation projects of fast charging infrastructure in the UK and the US and 12,700 driving days collected from 35 BEVs in the UK were analysed. Using multiple regression analysis, we examined the relationship between daily driving distance and standard and fast charging and demonstrated that fast chargers are more influential. Fast chargers enabled using BEVs on journeys above their single-charge range that would have been impractical using standard chargers. Fast chargers could help overcome perceived and actual range barriers, making BEVs more attractive to future users. At current BEV market share, there is a vital need for policy support to accelerate the development of fast charge networks.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Considerations for Corridor and Community DC Fast Charging Complex System Design

The Idaho National Laboratory (INL), a U.S. Department of Energy (DOE) national laboratory located in Idaho Falls, Idaho, has been DOE’s lead laboratory for the field testing of light-duty plug-in electric vehicles (PEVs), charging infrastructure, and other alternative vehicle technologies for 25 years. INL has tested and collected data from more than 17,000 charging stations, documenting efficiencies, charge profiles, and PEV drivers’ behaviors when using charging infrastructure. Based on the experience of INL staff and support personnel, DOE requested that INL perform three tasks: • Identify pertinent lessons learned from previous direct current (DC) fast charger (DCFC) deployment and data collection activities in order to perform an analysis of the experience to date with DC fast charging systems • Establish the criteria for siting DC fast charging systems, including access to current or future sizeable penetrations of PEVs and existing power, the potential to be used by local (intracity) as well as pass-through (intercity) PEV drivers, expandability, and accessible to the federal highway system • Develop a draft system specification that lists the components that will be incorporated in a DC fast charging complexes.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗