Wireless charging technology has been around for over 100 years
Here’s how it works, and why it could soon show up in everything from homes to robots.
It started with the ability to transmit electricity through the air connecting two circuits, a transmitter and a receiver.
Today, there are nearly a half dozen wireless charging technologies in use today compared to only one or two a decade ago..
They are all aimed at wireless revolution, everything from smartphones and laptops to kitchen appliances and cars.
This technology is revolutionizing the high tech industries
Wireless charging is now in our healthcare, automobiles and many manufacturing industries.
It offers the promise of increased mobility and smart advances as a result, which enables tiny devices their needed power many feet away from a charger.
How wireless charging works
There are three types of wireless charging:
- charging pads: tightly-coupled, short range charging;
- charging bowls: through-surface type, loosely-coupled, resonant charging;
- uncoupled radio frequency: (RF) wireless charging that allows a trickle charging capability at distances of many feet.
Tightly coupled inductive and loosely-coupled resonant chargers operate on the same principle of physics. As a result, in both the time-varying magnetic field induces a current in a closed loop of wire.
It works like this:
First of all, the use of a magnetic loop antenna to create a magnetic field.
This creates a current and is the result of resonant inductive charging or magnetic resonance.
It also enables power transmission at greater distances between transmitter and receiver which increases efficiency.
In addition, the coil size also affects the distance of power transfer.
The bigger the coil, or the more coils there are, the greater the distance a charge can travel.
Finally, most smartphone wireless charging pads provide copper coils that are only a few inches in diameter.
Therefore, this severely limits the distance over which power can travel efficiently.
Advancements in wireless charging technology
The use of resonance charging enables high levels of power to be transmitted efficiently. It also boosts the amount of energy that can be captured and used to charge a battery. Wireless charging up until now has largely remained with charging pads.
In terms of progress and industry readiness, charging pads have been shipping in volume since 2015. The newer charging bowls are really just starting to launch. Over 200 million wireless charging-enabled devices shipped in 2016. Almost all of them were using some form of inductive charging pad type of design.
Wireless charging pads utilize a copper transmitter charger. An on board chip set controls the power delivered to each device. A smart object detection ensures only valid objects receive a charge.