Wireless power transmitter and method of managing thereof

Abstract

A wireless power system including a power supply device configured to generate AC power; a transmitter configured to transmit the AC power generated by the power supply device; and a receiver configured to receive the AC power. The receiver includes a receiving unit to receive AC power through a resonance frequency band from the transmitter; a rectifying unit to rectify the received AC power to DC power; a DC-DC converter to convert the rectified DC power into a specific DC power required by a load; a voltage restricting unit disposed before the load; and a controller to detect a first rectified DC power, which is rectified from the received AC power, that is less than a predetermined threshold to prevent an instant overvoltage from being transferred to the load, to transmit, via a modulation unit through out-of-band communication at a specific frequency band other than the resonant frequency band, a signal to increase the AC power to be received from the transmitter and control the voltage restricting unit to allow the detected first rectified DC power to be transferred to the load in response to the detected first rectified DC power also being less than a charge quantity of the load, to detect a second rectified DC power, which is rectified from the received AC power, that is equal to or greater than the predetermined threshold to prevent the instant overvoltage from being transferred to the load, and to transmit, via the modulation unit, a signal to decrease the AC power to be received from the transmitter and control the voltage restricting unit to prevent the detected second rectified DC power from being transferred to the load in response to the detected second rectified DC power being equal to or greater than the predetermined threshold. Further, the predetermined threshold is different than the charge quantity of the load, and the transmitter includes a transmission resonant coil configured to transmit the AC power through the resonance frequency band to the receiver; and an out-of-band communication module configured to receive the signal from the receiver through the out-of-band communication.

What is claimed is: 
     
         1 . A wireless power system, comprising:
 a power supply device configured to generate AC power;   a transmitter configured to transmit the AC power generated by the power supply device; and   a receiver configured to receive the AC power,   wherein the receiver includes:   a receiving unit to receive AC power through a resonance frequency band from the transmitter;   a rectifying unit to rectify the received AC power to DC power;   a DC-DC converter to convert the rectified DC power into a specific DC power required by a load;   a voltage restricting unit disposed before the load; and   a controller to:   detect a first rectified DC power, which is rectified from the received AC power, that is less than a predetermined threshold to prevent an instant overvoltage from being transferred to the load,   transmit, via a modulation unit through out-of-band communication at a specific frequency band other than the resonant frequency band, a signal to increase the AC power to be received from the transmitter and control the voltage restricting unit to allow the detected first rectified DC power to be transferred to the load in response to the detected first rectified DC power also being less than a charge quantity of the load,   detect a second rectified DC power, which is rectified from the received AC power, that is equal to or greater than the predetermined threshold to prevent the instant overvoltage from being transferred to the load, and   transmit, via the modulation unit, a signal to decrease the AC power to be received from the transmitter and control the voltage restricting unit to prevent the detected second rectified DC power from being transferred to the load in response to the detected second rectified DC power being equal to or greater than the predetermined threshold,   wherein the predetermined threshold is different than the charge quantity of the load, and   wherein the transmitter includes:   a transmission resonant coil configured to transmit the AC power through the resonance frequency band to the receiver; and   an out-of-band communication module configured to receive the signal from the receiver through the out-of-band communication.