A project is underway in Edinburgh to assess whether wireless charging technology can support the introduction of more electric vehicles to the city council’s fleet and those of commercial organisations.
The £1.6m project, led by Flexible Power Systems, will do this by assessing shared charging hubs, dynamic charge scheduling across fleets, and high-power wireless charging for Light Commercial Vehicles. The project is being delivered in partnership with The City of Edinburgh Council and Heriot-Watt University.
Initially, four L2H1 variant Vauxhall Vivaro E vans will take to the streets, each fitted with a 75kW/h battery, Combined Charging System (CCS) rapid charging protocol, and 12kW onboard charger. To recharge, the van’s underslung vehicle assembly (VA) is positioned over a ground assembly (GA) to top the vehicle’s battery up in under an hour. A high-frequency inverter drive generates the 85kHz switching required for recharging via the GA.
In the video below, James Derby, chief electrical engineer at FPS describes how the VA charging coil incorporates a rectifier unit and integrates into the battery, charging mechanism and pre-charge circuitry, the latter allowing safe connection/disconnection of the VA to the battery system.
Funding for the trial is being provided by the UK government’s Office for Zero Emission Vehicles through Innovate UK.
Professor Phil Greening, deputy director of the Centre for Sustainable Road Freight, a joint initiative between Heriot-Watt University and Cambridge University, said wireless charging is a cornerstone technology and an essential requirement if commercial vehicles are to transport goods autonomously in the future.
“While shared infrastructure and collaboration have great potential to reduce the costs of decarbonising last-mile logistics, there are complex scheduling and commercial trade-offs to be considered,” he said.
Prof Greening explained that vehicles currently refuel in minutes, and once refuelled have ranges expressed in hundreds of miles. In the future, EVs refuelling will take tens of minutes and the resulting range is likely to be in tens of miles.
“This means that vehicles will have to coordinate with other vehicles about when and where they can recharge,” he told The Engineer. “Such coordination is also likely to mean that vehicles will have to forecast their energy state and book charging slots at limited facilities. This may result in vehicles having to adopt sub-optimal routes so they can be sure of accessing charging facilities.”
He continued: “This results in a new trade off: should the vehicle travel further – to pick up charge – or deliver later to pick up a charge closer to the ideal route? These problems are best addressed using real time sophisticated coordination platforms.”
The trial runs to April next year.