Today, the innovation is focused on separating the two coils and allowing a “sloppy” interface while still maintaining high efficiency, low cost and reasonable mechanical form factors.

Third generation systems offer the capability to radically improve mobility and enhance productivity for the marketplace.

After years in the backwoods, inductive wireless power technology has seen a recent resurgence both in the marketplace as well as in fundamental technical innovation. 

Of course, magnetic induction is at the core of every motor and generator in the world, however in this model the two coils are intertwined and fixed relative to each other. Today, the innovation is focused on separating the two coils and allowing a “sloppy” interface while still maintaining high efficiency, low cost and reasonable mechanical form factors. 

In this direction, we have seen steady progress such that today we see three distinct generations of wireless power technology. 

The first generation consisted of a very simple disconnection between the two coils using relatively low frequency for power transfer. These systems typically had large form factors, and were also heavy due to the use of ferrous core materials. 

They have been useful in situations where a contact based solution was not viable or hazardous. The most prominent consumer facing example of this technology has been the electric toothbrush. The second generation has attempted to enlarge the relative number of end applications by reducing the form factors and weight issues.

This has been done primarily by raising the frequency of power transfer. In order to support a reasonably efficient solution around the resonance point, generation two systems employ communication and controls systems to manage the power delivery process.

Generation two systems can support a wide range of consumer devices with reasonably small form factors. Nearly all of these systems, however, require very precise alignment to be operational, and cannot support multiple devices on a single coil. 

The most prominent example of this technology has been the recent Palm Pre announcement, but many startups such as eCoupled and Powermat are also trying to make inroads.

Generation three systems not only raise frequency, but fundamentally change the power electronics to naturally tolerate the “sloppy” interface between the two coils.

With this capability, significant freedom of movement can exist between the two coils and multiple devices can be handled concurrently. Startup companies such as WiPower and Witricity employ generation three solutions, and focus on different optimization points.

WiPower focuses on low-cost at the expense of very long distance. Witricity optimizes on distance with some impact on cost.

In either case, these generation three systems offer the capability to radically improve mobility and thus enhance productivity for the marketplace.

For more information visit WiPower.