- Electromagnetic Induction
Electromagnetic induction is the core theory of the mobile phone wireless charging system.When the current flows to a wire, it will generate a magnetic field around.The magnetic field is like a bridge, which brings the energy from one place to another. In the wireless charging system, alternating current will be transferred to the direct current by a power adapter. The direct current will fully transferred to the alternating current by the wireless charging module. All the energy will be transformed to the wireless charging coils. The coils will send the variational magnetic fields around. When the mobile phone coils enter into the magnetic fields, the coils will produce the induced current. The current will directly charging the mobile phone battery after rectification and stabilivolt. It is the most popular charging system because of the high efficiency and stability.
- Magnetic Resonance
When two coils which have same resonant frequency are close, it will happen strong magnetic resonance. In magnetic resonance wireless charging system, the coils from transmitting terminal will produce alternating magnetic fields by high frequency current. The magnetic field will produce induced current on the coils from receiving terminal.Compared with the electromagnetic induction, the magnetic resonance technology have longer charging distance and wider charging scope. However the cost is higher and the efficiency is lower.So, it is not popular in the market.
- Radio Wave
Radio wave wireless charging system is also a new technology which need to discover. Even though this technology is not widely used in the mobile phone applicant, it also provide a new idea about the wireless charging. The radio wave wireless charging system use radio wave in the space to covey the energy. It could convey long distance energy without considering the distance and direction. However the radio wave also face many challenges, security of the radio wave, energy transmission and so on. These factors affects the applicant of the radio wave wireless charging system.
All in all, every technology has its advantages and its limits. In the future, there will be more technology in wireless charging fields will appear. They will take more pleasure and convenience to us.
