Wireless Charging

Wireless battery charging or wireless inductive charging is a method for transferring electrical energy from a charger to a device without the need for a physical wire connection. Wireless charging is based on the principle of magnetic resonance, or Inductive Power Transfer (IPT). This is the process of transferring an electrical current between two objects through the use of coils to induce an electromagnetic field or to transfer the energy from one to another. The energy is transferred from the source to the receiver where it is typically used to charge the battery in the device.

The Mains voltage is converted into high frequency alternating current and this is sent to the transmitter coil by the transmitter circuit. The alternating current induces a time varying magnetic field in the transmitter coil. Current flowing within the transmitter coil induces a magnetic field which extends to the receiver coil. The magnetic field generates the current within the receiver coil of the device. Current flowing within the receiver coil is converted into direct current (DC) by the receiver circuit, which can then be used to charge the battery. The process of energy flow transmitted between the transmitter and receiver coil is also referred to as magnetic or resonant coupling and is achieved by both coils resonating at the same frequency.

It’s through this process that power is safely transferred over an air gap. As well as any non-metal object that might exist between the coils. Such as wood, plastic or granite. This makes wireless/inductive charging ideal for use with many portable devices such as mobile phones and other wireless applications.