Wireless Charging of Electric Cars

Qualcomm Halo – Wireless Electric Vehicle Charging

  • Twitter
  • Facebook
  • Google+
  • Pinterest

One of the biggest problems with electric vehicles is charging them. Consider a situation when the battery of your cell phone is dying and you are unable to find an electric charging spot or source where you can plug in and charge your cell phone. Same is the case with electric cars. Imagine how difficult it would be when the battery of your car is running out of charge during the drive in an area where there is no spot available for charging.

Qualcomm Halo Wireless Electric Vehicle Charging (WEVC) technology seeks to solve this problem with wireless inductive charging for electric vehicles. Qualcomm Halo WEVC has basically taken inductive charging to the next level by making it possible to send kilowatts over an air gap of hundreds of millimeters while still maintaining high energy transfer of electricity. This is the same technology which is generally used in wireless charging of cell phones placing them on the wireless charging dock or which you probably already have seen in your electric toothbrushes.

Halo WEVC consists of two parts:

  • a charging plate that attaches to the bottom of the vehicle
  • a charging mat that can be placed on or below the ground

Inductive charging uses magnetism to transfer power, and Halo WEVC can transfer up to 3.5 kilowatts of power at greater than 90 percent efficiency. That is as good as, or even better than the wired charging.

In other words, the car should charge wirelessly as fast as it would if it is wired. This technology is very tolerant and flexible. Meaning thereby that it is not necessary to park the car precisely over the mat. Parking the car close enough would also charge the car as efficiently as it would if it was exactly on the top.

The London Trial

The London Trial by Qualcomm
Qualcomm Carrying Out Trial of its Wireless Electric Vehicle Charging Technology in London Supported by the then U.K. PM, David Cameron (left)

While Halo WEVC is still in prototype mode, Qualcomm announced that it will launch a trial of the prototype in London. The trial was conducted with a fleet of 50 vehicles including Delta Motorsport, Delta E4 Coupe, and Renault’s Fluence ZE EV. The trial spanned for about over two years. For this trial, Qualcomm worked with Chargemaster, a charging station specialist with several installations in both private and public areas across the city. The company says that adding Qualcomm Halo WEVC to those sites was less expensive than installing new sites since up to 70 percent of the charging bay cost is in providing the utilities. Qualcomm said that the objectives of the London trial were;

  1. To evaluate the commercial viability of the wireless charging of electric vehicles
  2. To develop a further understanding of the issues relating to the integration of WEVC technology into EVs
  3. To build knowledge associated with the development of WEVC into a megacity
  4. To gain user feedback on the use of WEVC enabled electric vehicles

Dynamic Electric Vehicle Charging

Electric Car Charging

This new technology of charging the car while driving is called dynamic electric vehicle charging (DEVC), the technology is integrated into a specially-built track, cutting out the need for electric cars to stop at charging stations. The breakthrough could pave the way for the building of more roads capable of charging cars, and an eventual move to other electric vehicles. The key features of DEVC system are as under;

  • Charging over big gaps

Unlike some other inductive charging solutions that need pads to be closely aligned or almost touching, Qualcomm Halo technology delivers high energy transfer over a wide air gap. The idea is even applicable keeping in mind the ground clearance of an SUV.

  • Charging even when misaligned

The charging pad’s multi-coil design delivers high energy–transfer efficiency and high power even if pads are misaligned. The power is estimated to be between 3.3 KW to 6.6 KW.

  • Efficiency comparable to cables

Cable does not offer significantly better power transfer efficiency as they have losses too because of the material being used. Qualcomm Halo actually benefits from its lack of physical connection with an efficiency that increases with power level. It almost gives 90% of the result as used with cables.

Based on the Qualcomm Halo wireless electric vehicle charging technology (WEVC), the DEVC tech can charge two vehicles on the same track simultaneously. The technology is flexible enough that vehicles can pick up charge while traveling forwards and in reverse even.

The technology was demonstrated at the 100-metre FABRIC test track at Satory Versailles, France, where the two vehicles were able to charge at up to 20 kilowatts while traveling at high speed.

The pseudo-acronym FABRIC stands for feasibility analysis and development of on-road charging solutions for future electric vehicles and is a €9 million (£7.6m) project, mostly funded by the European Commission. Built by VEDECOM, the FABRIC test track was fitted with charging tech by Qualcomm, while VEDECOM and Renault worked together to equip two Renault Kangoo vehicles with the receiving part of the technology.

FABRIC Track
The FABRIC Test Track Being Laid – Built by VEDECOM, Fitted with Charging Tech by Qualcomm

The FABRIC project began in January 2014 and is scheduled to continue until December 2017. The initiative is being undertaken by 25 organizations from nine European countries, including car makers, suppliers, and automotive research groups. It is hoped the breakthrough in dynamic charging will make electric vehicles a far more attractive option for car users. Here are the systems that make up the full Qualcomm Halo DEVC system at FABRIC:

  1. The 100-meter track comprised of 4 x 25-meter stubs, each running from its own power supply.
  2. Each stub powers 14 Base Array Network (BAN) blocks coupled magnetically into the backbone cable.

The power is transmitted across the air gap to two 10 kW vehicle pads (VP) located under the EV. The vehicle system converts the 85-kHz AC and delivers DC power as requested to the EV’s battery management system. Qualcomm Halo technology was designed with interoperability in mind. This means EV drivers will be able to wirelessly charge at any WEVC Bay independent of which supplier provides the hardware, or EV they drive. BP magnetics support a range of power transfer levels and varying vehicle ground clearances from SUVs to roadsters and they are also suitable for the surface, flush and buried installations.

Companies like Honda are also testing the concept, but with a higher charging rate of 180 kW at a speed of 155 km/h. There are still some ways to go before we see dynamic charging become a part of the streets. EVs will still have to rely on charging stations or home sockets to power up. The DEVC technology, however, if tested successfully, can be used in say highways, to give some extra miles to EVs and autonomous cars.

Qualcomm has handed over the DEVC charging system to VEDECOM, which will evaluate the operation, safety and efficiency of energy transfer to the vehicles for a wide range of practical scenarios, including vehicle identification and authorisation on entering the track, power level agreement between track and vehicle, speed and alignment of vehicle along the track.

Leave a Reply

Your email address will not be published.
Required fields are marked *