Detailed explanation of automobile wireless charging principle

The wireless charging technology of electric vehicle transmits the electric energy in the form of high-frequency alternating magnetic field to the electric energy pickup mechanism at the receiving end of the vehicle through the buried power supply guide rail, and then supplies power to the on-board energy storage equipment.

When charging is started, the power transmitter PTx generates alternating current through its coil, thus generating an alternating magnetic field according to Faraday's law. This magnetic field is picked up by the coil in the power receiver PRx and converted back to DC current, which can be used by the power converter to charge the battery.

A key feature of magnetic field is that it can pass through any nonmetallic and nonferrous materials, such as plastic, glass, water, wood and air. In other words, there is no need for wires and connectors between the power transmitter PTx and the power receiver PRx, thus realizing the wireless charging function.

Extended data:

App application

Volvo has added a wireless induction charging device to its classic C30 model, so that when charging the car, the driver only needs to drive the car to a fixed position without touching the charging cable.

The device consists of a battery, a charging sensor, an AC /DC converter and a control system. It takes about 20 minutes to fully charge the battery by feeding alternating current into the ground charging board, and it usually takes 6-8 hours if household lighting electricity is used.

References:

Baidu Encyclopedia-Wireless Charging Technology for Electric Vehicles