A practical multiphase IPT system for AGV and roadway applications

Recent advances in Inductive Power Transfer (IPT) technology have made it possible to transfer enough power across an air gap of sufficient size that electric vehicles can receive operational power and be charged while they are in motion on a roadway. However, in order to provide the vehicle with the required tolerance to lateral movement, bulky pickups or complex track arrangements are required. The challenge is to provide the vehicle as much freedom of movement as possible so that drivers are not artificially restricted, while utilizing a simple and low cost pickup, track and power supply. This paper will show that a simple, low cost two-phase track and power supply system can provide similar benefits to a more complex three-phase system, while also lowering the system cost with a simpler installation. A quadrature pickup provides additional benefits in maintaining a constant power transfer across the width of the roadway. Used together, these provide the vehicle with high freedom of movement, and a low total system cost.