An Appropriate Magnetic Coupling Co-Efficient for the Design and Comparison of ICPT Pickups

Coupling factor k is widely used when referring to magnetically coupled circuits such as transformers and induction motors. It is also used in the system-level design of inductively coupled power transfer systems, but for distributed applications it does not provide a useful measure to compare the magnetic performance of different pickup designs. As such, a more appropriate magnetic coupling coefficient, kappa
_phi
, is proposed. It is simple to determine, provides an excellent measure as the magnetic efficiency of a pickup design, and provides a mechanism to decouple the design of the magnetic geometry of a pickup from the rest of the system design. It can be incorporated into traditional lumped-circuit models, providing a specific reference to the system's underpinning magnetic geometry which can often appear invisible in traditional lumped-circuit models