Energy

A New Milestone for Electric Car Charging

Electric vehicles have, in the past years, been making remarkable leaps to the mainstream technology and day to day mobility. These vehicles are also more long-term cost-effective as compared to internal combustion counterparts. However, despite all this hype and technology wizardry, EVs are still inferior to conventional cars when it comes to driving range, and also they take a lot of time to charge. This defect has been a significant area of consideration among consumers transitioning from gas to electric vehicles. But, imagine how convenient it will be to have an electric car that never stops to refuel. Two Stanford University engineers have designed a wireless technology that allows electric vehicles to recharge themselves as they speed up along roads with a unique design feature for “refueling.” 

This technology has various applications, such as recharging drones hovering over rooftops and robots on factory floors. Wireless charging is not a very new concept as some smartphones are already using this technology through wireless charging pads, although the phones need to be sitting still. Applying the same technique to an electric car is not very different from plugging it in at a charging station, as the vehicle needs to be stationary, and that is why engineers at Stanford have built a system that can charge objects even in motion.

In wireless charging, wireless chargers transmit electricity by creating a magnetic field that oscillates at a frequency, creating a resonating vibration in magnetic coils on the receiving device. The only limitation to this process is that the resonant frequency changes if the distance between the source and the receiver changes even by a small fraction. According to the scientists, to achieve this, one needs to incorporate an amplifier and a feedback resistor that allows a system to adjust operating frequency automatically, as the distance between the charger and the moving object changes.

In their latest development, the scientists were able to illustrate how to boost a system’s wireless transmission efficiency to an overwhelming 92% by having an efficient switch mode amplifier. This means that at a distance of two to three feet, their prototype can transmit 10 watts of electricity, which is more than fast enough to re-supply a speeding vehicle. Another exceptional feature of the wireless charging system is that it does not pose a health risk to users as the magnetic fields are within the safety guidelines. This means that the magnetic field can transmit electricity through people literally, without them feeling anything.

Although it could take time before this advance in technology, which scientists are considering as a Holy Grill for electric charging, is put to use on a broader scale, it’s a significant development in the world of science and technology. It will one day revamp the automotive industry, offering a better and convenient transport system with self- charging cars.