Field of the Disclosure
The present disclosure relates to the field of power electronics, and more particularly, to a power receiver, a resonance-type contactless power supply and a control method.
Description of the Related Art
Contactless power supply is widely used in electronic products, especially in low-power electronic products such as cellular phones, MP3 players, digital cameras, laptop computers, and the like, due to their convenience and availability. A conventional resonance-type contactless power supply typically has a resonance and magnetic coupling circuit including a transmitting coil L1 and a receiving coil L2. The transmitting coil L1 and other components in a power transmitter constitute a transmitter-side resonant circuit. The receiving coil L2 and other components in a power receiver constitute a receiver-side resonant circuit. Electric energy is transferred in a contactless manner when the transmitter-side resonant circuit and the receiver-side resonant circuit have the same resonance frequency. The receiver-side resonant circuit is coupled to the transmitter-side resonant circuit by electromagnetic field, and thus resonates when the transmitter-side resonant circuit resonates. Typically, the above resonance frequency is referred to as a self-inductance resonance frequency.
However, there may be varied load when electric energy is supplied. The conventional contactless power supplies cannot maintain system efficiency while the load varies.
USPTO Backgrounds
USPTO Backgrounds