As of my last knowledge update in September 2021, transformers have not been widely used in electric vehicle (EV) wireless charging systems. In wireless charging systems, the primary component responsible for transferring power without direct electrical contact is typically an inductive coupling system, not a traditional electromagnetic transformer.
Inductive charging systems work based on the principles of electromagnetic induction, where a primary coil generates a magnetic field, and a secondary coil in the EV picks up this magnetic field, inducing a current that charges the vehicle's battery. The primary and secondary coils are generally designed to be in close proximity to each other to achieve efficient power transfer.
Traditional transformers, on the other hand, are used for stepping up or stepping down AC voltages in electrical distribution systems. They are not suitable for wireless power transfer over distances, as they require direct physical contact between their windings.
However, there have been advancements in wireless charging technology since my last update, and it's possible that new developments have emerged. Some researchers and companies are exploring different methods, such as using resonant inductive coupling or even using high-frequency transformers for wireless power transfer.
It's essential to consult more recent sources and research papers to get up-to-date information on the latest advancements in wireless charging systems for electric vehicles. As technology evolves, new and innovative solutions may have been developed.