Inductive Coupling: Power of the Future?
SplashPower claims to be offering practical wireless power solutions in the near future.
According to Wikipedia:
In electronics, inductive coupling refers to the transfer of energy from one circuit component to another through a shared magnetic field. A change in current flow through one device induces current flow in the other device. The two devices may be physically contained in a single unit, as in the primary and secondary sides of a transformer, or may be separated as in the antennae on a transmitter and a receiver. Coupling may be intentional or unintentional. Unintentional coupling is called cross-talk, and is a form of interference. Inductive coupling favors low frequency energy sources. High frequency energy sources generally use capacitive coupling.
I wonder what the range is on these things!
I think the range is extremely limited (ie, your phone has to be sitting on the platform). If it is any more than a foot, I’d be very surprised. If it is more than a foot, the thing might really screw up any electronics you had near it. Also, its efficiency would be terrible, as it would take a lot of current to induce a magnetic field that would be big enough from that distance to, in turn, induce the current to charge the phone batteries.
What I would like to know about this product is how they induce a current strong enough to charge the battery without affecting the other electronics in the phone. That changing magnetic field would induce a current in all of the conductors within range. My phone charger says it outputs 0.7 A! That’s more than most communications electronics would be rated for I believe.
I can’t see this technology becoming something that you can use while walking around talking… It might happen someday, but I’m thinking it would be from microwaves, or some electromagnetic radiation, instead of simple induction.
There was a mention of this in a recent magazine. The product was a deskpad. You electronic devices need to be modified/adapted to use this. The idea is that each evening you simply place your devices on top of the pad and they’ll be charged overnight and ready to go in the morning. Not practical yet but the idea can be developed further.
Also, back in the “OLD” days, I heard farmers in the midwest who lived near powerlines would wind up coils of wire in a ring, attach a light bulb and have free wireless, portable light when they go milk the cows.
While inductive coupling may not seem practical for every day uses it is an intriguing technology for biomedical applications. Batteries cannot supply enough power to implants and MEMS that stimulate muscles and may also see use in wireless capsule endoscopy since batteries are a limiting factor on their lifetime and size.
If only they would have allowed Nikola Tesla to fully develop this technology back in 1901, we’d probably all be experiencing the benefits of wireless power today.