Wireless power charging system

This application claims the benefit of Korean Patent Application No. 10-2007-0123750 filed on Nov. 30, 2007, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

1. Field of the Invention

The present invention relates to a wireless power charging system, and more particularly, to a short-distance wireless power charging system, which has a wireless power transmission apparatus formed to charge a plurality of wireless power receiving apparatuses located in a short distance therefrom, wherein the total charging time for a plurality of wireless power receiving apparatuses can be saved.

2. Description of the Related Art

Portable electronic devices, such as cellular phones, personal digital assistants (PDAs), portable media players (PMPs), digital multimedia broadcasting terminal (DMB terminals), MPEG audio layer 3 (MP3) players or notebook computers, cannot be plugged into the regular power at home or office since they are generally used while the users are moving. Accordingly, the portable electronic devices are equipped with batteries or rechargeable batteries.

A charging system has been used to charge electric power, supplied from a regular power source, to the batteries or a battery pack of the portable devices via power supply lines or power supply connectors. However, when the charger and the batteries are connected or disconnected to replenish the electric power of the batteries with this connector supply system, an instant discharge may happen because of the potential differences between the charger connector and the battery connector. Hence the foreign substances will be gradually gathered on both connectors and finally there may be a fire disaster. Further, the collected humidity thereon will cause the discharge of the battery and other problems will be involved like the declining battery life, the low battery quality, and so on.

To solve the above-mentioned problems of the charging system using the power supply connectors, non-contacting charging systems have been developed. In this non-contacting charging system in accordance with the prior art, the device having the battery to be charged is placed over the primary coil of the non-contacting charging system and the battery will be charged by the secondary coil of the battery. The battery is charged with the induced electricity from the induced electromotive force of the secondary coil by the generated magnetic field from the primary coil.

The conventional non-contacting charging systems with the prior art can only be used to supply the electricity to the portable devices. There are limited practical uses because they cannot be used in various alternatives.

Besides, if a metal is placed inside the effective radius of the generated magnetic field of the primary coil, there would be a lot loss of the electricity in the primary coil and non-contacting charging system may be damaged.

To solve the above-mentioned problems, the present invention is directed to a wireless power charging system formed to charge a plurality of wireless power receiving apparatuses placed in a short distance from a wireless power transmission apparatus, wherein the total charging time for a plurality of wireless power receiving apparatuses will be saved.

Moreover, when a plurality of wireless power receiving apparatuses are fully charged, the wireless power transmission system will be automatically changed to a standby mode, wherein the initial pulse signal is sending out. By doing so, the charging efficiency will be maximized while the loss of the electricity will be minimized.

According to an aspect of the present invention, there is provided a wireless power charging system for charging one or a plurality of wireless power receiving apparatuses in a short distance from a wireless power transmission apparatus. The wireless power transmission apparatus includes a power transmission apparatus case as an outside body housing a main control unit and a resonant converter unit, which transmit an electric signal to one or via a resonance signal generated from a primary charge core; an output signal conversion module for transmitting the converted electric signal to the resonant converter unit by the control signal from the main control unit; and a received signal process module, which processes a signal transmitted from the wireless power receiving apparatus via the primary charge core and sends the processed signal out to the main control unit.

Hereupon the resonant converter unit may include an R-L-C series-parallel resonant converter.

The power transmission apparatus case may include a power on/off switch on the front side thereof; an input panel for signal input; and a display panel showing the charging status of the wireless power receiving apparatus and normal/abnormal status of the wireless power transmission apparatus. The power transmission apparatus further includes a power supply unit installed inside the power transmission apparatus case.

The main control unit may include a power supply block connected with the power supply unit for the power supply to the wireless power transmission apparatus; a signal output block for sending the display signal to show the status on a display panel; a gate output signal process block coupled with an output signal conversion module for transmitting a power signal transferred from the primary charge core; a received signal process block for processing a signal transmitted from a received signal process module, which processes the signal transmitted from the wireless power receiving apparatus; and a main controller which controls the power supply block, the signal output block, the gate output signal process block, and the received signal process block.

Furthermore, the wireless power receiving apparatus may include a secondary charge core fronting the primary charge core of the wireless power transmission apparatus in order to receive the power signal via the resonant with the magnetic field; a received power signal conversion module connected with the secondary charge core for converting the received power signal; a charge circuit block linked with the received power signal conversion module in order to charge the battery cell; a protection circuit block formed between the charge circuit block and the battery cell for detecting the charged current into the battery cell and sending the charging status of the battery cell to the wireless device control module; a voltage regulator block for the power supply to the wireless device control module; and a wireless device control module, which controls the received power signal conversion module, the charge circuit block, the protection circuit block, and the voltage regulator block.

The present invention formed with the above-mentioned figures is constructed to charge a plurality of wireless power receiving apparatuses located in a short distance from the wireless power transmission apparatus, wherein the advantageous effect is that the total charging time for a plurality of wireless power receiving apparatuses can be saved.

Moreover, when a plurality of wireless power receiving apparatuses are fully charged, the wireless power transmission system will be changed to a stand-y mode where the initial pulse signal is sending out. By doing so, the charging efficiency will be maximized while the loss of electric power will be minimized.