Wireless charging technology II

2021-06-28 09:46:35
       1、 Basic principles

        Electromagnetic induction

        The alternating current of a certain frequency in the primary coil generates a certain current in the secondary coil through electromagnetic induction, thus transferring the energy from the transmission end to the receiving end. At present, electromagnetic induction is the most common charging solution. In fact, there is not much mystery in the technical realization of electromagnetic induction solution. BYD, a local Chinese company, applied for the patent of non-contact induction charger as early as December 2005, and used electromagnetic induction technology

        Magnetic resonance

        It is composed of an energy sending device and an energy receiving device. When the two devices are tuned to the same frequency, or resonate at a specific frequency, they can exchange energy with each other. It is a technology currently being studied. The research team led by Marin soljacic, a physics professor at MIT, used this technology to light a 60 watt light bulb two meters away, And it's called WiTricity. The coil used in this experiment has a diameter of 50cm, which can not be commercialized. If the coil size is to be reduced, the received power will naturally decrease.

        Radio wave type

        This is a relatively mature technology, similar to the ore radio used in the early days. It mainly consists of a microwave transmitting device and a microwave receiving device. It can capture the radio wave energy bouncing back from the wall and maintain a stable DC voltage while adjusting with the load. This method only needs a transmitter installed on the wall plug and a "mosquito type" receiver that can be installed on any low voltage product.