Abstract:
There is provided a wireless power transmitting device capable of simply being carried by a user and wirelessly transmitting a power to a power receiving device with a high transmission efficiency regardless of time and space. The wireless power transmitting device includes a power storage unit configured to store a direct current power, and a power transmitting unit configured to be operated by the direct current power stored in the power storage unit and to wirelessly transmit the power to a power receiving device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a national stage of International Application No. PCT/KR2012/011322, filed Dec. 21, 2012, which claims priority to U.S. Provisional Application No. 61/579,203, filed Dec. 22, 2011. All disclosures of the documents named above are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a device and a method for wirelessly transmitting a power capable of easily being carried by a user and wirelessly transmitting a power to a power receiving device regardless of time or location. 
     Description of the Background Art 
     In general, a power receiving device for supplying an operating power is attached to various mobile terminals such as a cellular phone or a PDA (Personal Digital Assistant). 
     The power receiving device receives a power supplied from an external charging device, and supplies the received power to the mobile terminal as the operating power. 
     The power receiving device may include a battery that is charged with the power, and a charging/discharging circuit that receives the power supplied from the external charging device to charge the battery with the power, and that discharges the power charged in the battery to supply the discharged power to the mobile terminal as the operating power. 
     As a method for electrically connecting the charging device with the power receiving device, a terminal connecting method which directly connects a power output terminal of the charging device to a power input terminal of the power receiving device through a cable and a connector is widely known. 
     The power output terminal of the charging device and the power input terminal of the power receiving device have different potentials from each other. 
     Accordingly, when a terminal of the charging device from which the power is output and a terminal of the power receiving device to which the power is input are connected to each other or are separated from each other, instantaneous discharging may be caused due to a potential difference. 
     The instantaneous discharging causes abrasion in the terminal of the charging device and the terminal of the power receiving device. Further, when a foreign substance exists in the terminal of the charging device or the terminal of the power receiving device, heat is generated in the foreign substance due to the instantaneous discharging, so that there is a concern that a negligent accident such as fire may occur. 
     Furthermore, the power charged in the battery of the power receiving device is naturally discharged to the outside through the terminal of the power receiving device due to moisture, so that a lifespan of the power receiving device may be shortened, and performance thereof may be degraded. 
     In recent years, in order to solve various problems of the terminal connecting method, a wireless power transmitting device that wirelessly transmits the power to the power receiving device has been proposed. 
     The wireless power transmitting device wirelessly transmits the power by using, for example, an electromagnetic induction method. The power receiving device receives the power that is wirelessly transmitted from the wireless power transmitting device, and charges the battery with the received power. 
     Much research and development has gone into allowing the wireless power transmitting device to stably transmit the power with a high efficiency in a wireless manner and allowing the power receiving device to receive the power transmitted from the wireless power transmitting device to charge the battery with the power. 
     The wireless power transmitting device is typically operated by an alternating current power input from the outside to wirelessly transmit the power to the power receiving device. 
     Accordingly, the wireless power transmitting device can wirelessly transmit the power to the power receiving device only in a place where the alternating current power is supplied from the outside, and does not wirelessly transmit the power to the power receiving device in a place where the alternating current power is not supplied. 
     SUMMARY OF THE INVENTION 
     Technical Problem 
     An object of the present invention is to provide a device and a method for wirelessly transmitting a power capable of easily being carried by a user and wirelessly transmitting a power to a power receiving device regardless of time or location. 
     Another object of the present invention is to provide a device and a method capable of wirelessly transmitting a power to a power receiving device by storing the power to a power storage unit and using the power stored in the power storage unit. 
     Another object of the present invention is to provide a device and a method for wirelessly transmitting a power which receives the power from the outside in a wired or wireless manner to store the power in the power storage unit. 
     The objects of the present invention are not limited to the aforementioned technical objects, and other technical objects that are not mentioned should be clearly understood by those skilled in the art from the following description. 
     Technical Solution 
     An exemplary embodiment of the present invention provides a wireless power transmitting device including a power storage unit configured to store a direct current power; and a power transmitting unit configured to be operated by the direct current power stored in the power storage unit and to wirelessly transmit the power to a power receiving device. 
     The power storage unit and the power transmitting unit may be respectively provided in separate cases, and may be connected by a cable. 
     The power storage unit and the power transmitting unit may be integrally provided in a single case. 
     The power storage unit and the power transmitting unit may be respectively provided in separate cases, and may be slidably combined. 
     The power storage unit may further include an alternating/direct current converter configured to convert an external alternating current power to a direct current power; a battery configured to store the direct current power and to output the stored direct current power to the power transmitting unit; and a charging unit configured to charge the battery with the direct current power converted by the alternating/direct current converter under the control of the power transmitting unit. 
     The power storage unit may include a power receiving coil configured to wirelessly receive an external alternating current power; a rectifier configured to rectify the alternating current power received by the power receiving coil to the direct current power; a battery configured to store the direct current power and to output the stored direct current power to the power transmitting unit; and a charging unit configured to charge the battery with the direct current power rectified by the rectifier under the control of the power transmitting unit. 
     The power storage unit further may include an alternating/direct current converter configured to convert the external alternating current power into the direct current power; and a power transmitting switch that is provided between the alternating/direct current converter and the charging unit to be switched under the control of the power transmitting unit. 
     The power storage unit further may include a first signal receiving unit configured to receive a signal transmitted from an external wireless power transmitting device through the power receiving coil to provide the received signal to the power transmitting unit; and a first signal transmitting unit configured to transmit a signal generated by the power transmitting unit to the outside through the power receiving coil. 
     The power transmitting unit may include a power transmitting coil configured to wirelessly transmit an alternating current power; and a power transmitting controller configured to apply the alternating current power to the power transmitting coil to control such that the applied alternating current is transmitted. 
     The power transmitting unit further may include a driving driver configured to amplify a PWM driving signal generated by the power transmitting controller; and a series resonance type converter configured to switch the direct current power stored in the power storage unit to generate the alternating current power in response to the PWM signal amplified by the driving driver, and to apply the generated alternating current power to the power transmitting coil. 
     The power transmitting unit further may include a second signal receiving unit configured to receive a signal transmitted from the power receiving device through the power transmitting coil to provide the received signal to the power transmitting controller; and a second signal transmitting unit configured to transmit a signal generated by the power transmitting controller to the power receiving device through the power transmitting coil. 
     Another exemplary embodiment of the present invention provides a method for wirelessly transmitting a power. The method includes charging a battery with a power received by a power receiving coil from the outside under the control of a power transmitting controller; and applying the power charged in the battery to a power transmitting coil under the control of the power transmitting controller to wirelessly transmit the power to the outside. 
     The operation of charging a battery with a power received by a power receiving coil from the outside under the control of a power transmitting controller may include transmitting, by the power transmitting controller, an ID signal when an ID request signal is received, and determining whether the power is received through the power receiving coil; and when the power is received, charging the battery with the received power. 
     The method may further include charging, by the power transmitting controller, the battery with an output power of an alternating/direct current converter when the power is not received by the power receiving coil from the outside. 
     The method may further include determining, by the power transmitting controller, a power charging status of the battery; and generating, by the power transmitting controller, a charging status signal including the power charging status to transmit the generated charging status signal to the outside through the power receiving coil. 
     The operation of applying the power charged in the battery to a power transmitting coil under the control of the power transmitting controller to wirelessly transmit the power to the outside may include detecting a power receiving device through the power transmitting coil; converting the power charged in the battery into an alternating current power under the control of the power transmitting controller when the power receiving device is detected; and applying the converted alternating current power to the power transmitting coil to wirelessly transmit the alternating current power to the outside. 
     Still another exemplary embodiment of the present invention provides a wireless power transmitting device including a power transmitting coil configured to wirelessly transmit a power and to wirelessly receive the power; a power storage unit configured to store the power received by the power transmitting coil; and a power transmitting controller configured to control the power received by the power transmitting coil to be stored in the power storage unit, and to apply the power stored in the power storage unit to the power transmitting coil to wirelessly transmit the power to the outside. 
     The power storage unit may include a rectifier configured to rectify the power received by the power transmitting coil to a direct current power; a battery configured to store the power; and a charging unit configured to charge the battery with the direct current power rectified by the rectifier under the control of the power transmitting controller. 
     The power storage unit further may include an alternating/direct current converter configured to convert an alternating current power into a direct current power; and a power transmitting switch configured to output the converted direct current power by the alternating/direct current converter to the charging unit under the control of power transmitting controller. 
     Still another exemplary embodiment of the present invention provides a wireless power transmitting device that may further include a driving driver configured to amplify a PWM driving signal generated by the power transmitting controller; a series resonance converter configured to switch the direct current power stored in the power storage unit to generate the alternating current power in response to the PWM signal amplified by the driving driver, and to apply the generated alternating current power to the power transmitting coil; and a transmitting/receiving switch configured to be switched under the control of the power transmitting controller to apply the alternating current power generated by the series resonance converter to the power transmitting coil, and to output the power received by the power transmitting coil to the power storage unit. 
     Still another exemplary embodiment of the present invention provides a method for wirelessly transmitting a power. The method includes storing a power received through a power transmitting coil from the outside in a power storage unit under the control of a power transmitting controller; and applying the power stored in the power storage unit to the power transmitting coil to wirelessly transmit the power to the outside under the control of the power transmitting controller. 
     The operation of storing a power received through a power transmitting coil from the outside in a power storage unit under the control of a power transmitting controller may include transmitting, by the power transmitting controller, an ID signal through a power transmitting coil when an ID request signal is received, and determining whether the power is received through the power transmitting coil; and when the power is received, charging a battery with the received power. 
     Still another exemplary embodiment of the present invention provides a method for wirelessly transmitting a power. The method may further include charging, by the power transmitting controller, the battery with an output power of an alternating/direct current converter when the power is not received by the power transmitting coil from the outside. 
     Still another exemplary embodiment of the present invention provides a method for wirelessly transmitting a power. The method may further include determining, by the power transmitting controller, a power charging status of the battery; and generating, by the power transmitting controller, a charging status signal including the power charge status to transmit the generated charging status signal to the outside through the power receiving coil. 
     The operation of applying the power stored in the power storage unit to the power transmitting coil to wirelessly transmit the power to the outside under the control of the power transmitting controller may include detecting a power receiving device through the power transmitting coil: and applying the power charged in the battery to the power transmitting coil to wirelessly transmit the power to the outside under the control of the power transmitting controller when the power receiving device is detected. 
     Advantageous Effects 
     According to a wireless power transmitting device of the present invention, a power storage unit is provided to charge a power, and a power transmitting unit is operated by the power charged in the power storage unit to wirelessly transmit the power to a power receiving device. 
     Accordingly, a user can easily carry the wireless power transmitting device and wirelessly transmit the power to the power receiving device regardless of time or location. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Hereinafter, the present invention will be described in more detail, in connection with embodiments that do not limit the present invention, with reference to the accompanying drawings, and the same part will be assigned the same reference numeral in the drawings. 
         FIG. 1  is a block diagram illustrating a configuration of one embodiment of a wireless power transmitting device of the present invention, 
         FIGS. 2A to 2C  are diagrams describing usage examples of the one embodiment of the wireless power transmitting device of the present invention, 
         FIG. 3  is a signal flowchart illustrating an operation of a power transmitting controller according to one embodiment of a method for wirelessly transmitting a power of the present invention. 
         FIG. 4  is a signal flowchart illustrating a power transmitting operation in the method for wirelessly transmitting a power of the present invention, 
         FIG. 5  is a block diagram illustrating a configuration of another embodiment of the wireless power transmitting device of the present invention, 
         FIGS. 6A to 6C  are diagrams describing usage examples of the another embodiment of the wireless power transmitting device of the present invention, 
         FIG. 7  is a signal flowchart illustrating an operation of the power transmitting controller according to another embodiment of the method for wirelessly transmitting a power of the present invention, 
         FIG. 8  is a block diagram illustrating a configuration of still another embodiment of the wireless power transmitting device of the present invention, 
         FIGS. 9A to 9C  are diagrams describing usage examples of the still another embodiment of the wireless power transmitting device of the present invention, and 
         FIG. 10  is a signal flowchart illustrating an operation of the power transmitting controller according to still another embodiment of the method for wirelessly transmitting a power of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The following detailed description is merely an example, and is merely illustrative of embodiments of the present invention. Further, the principle and concept of the present invention are provided for the purpose of the most useful and easy description. 
     Therefore, it is appreciated that detailed structures unnecessary to understand the essential features of the present invention have not been provided, and various embodiments that are implemented by those skilled in the art in the substance of the present invention are exemplified through the drawings. 
       FIG. 1  is a block diagram illustrating a configuration of one embodiment of a wireless power transmitting device of the present invention. Here, reference numeral  100  denotes a power storage unit that stores a power, and reference numeral  200  denotes a power transmitting unit that is operated by the power stored in the power storage unit  100  to wirelessly transmit the power to a power receiving device (not illustrated in the drawing). 
     The power storage unit  100  may include an alternating/direct current converter  110 , a charging unit  120 , and a battery  130 . 
     The alternating/direct current converter  110  converts an alternating current power input through a power plug P from the outside into a direct current power. 
     The charging unit  120  is configured to charge the battery  130  with the direct current power output from the alternating/direct current converter  110  under the control of the power transmitting unit  200 , and provides power charging information of the battery  130  to the power transmitting unit  200 . 
     The battery  130  supplies the charged power to the power transmitting unit  200 , as an operating power. 
     The power transmitting unit  200  may include a power transmitting controller  210 , a driving driver  220 , a series resonance converter  230 , a plurality of power transmitting coils  240  ( 240 - 1 ,  240 - 2 ), a signal receiving unit  250 , and a signal transmitting unit  260 . 
     The power transmitting controller  210  generates an ID request signal to request an ID signal to the power receiving device, and generates a driving signal to wirelessly transmit the power to the power receiving device when the ID signal is received from the power receiving device. For example, the power transmitting controller  210  generates a PWM (Pulse Width Modulation) driving signal to control such that the power is wirelessly transmitted to the power receiving device. 
     Furthermore, when a charging status signal is received from the power receiving device, the power transmitting controller  210  controls such that the power is wirelessly transmitted to the power receiving device in response to the received charge status signal. 
     The driving driver  220  amplifies the PWM driving signal generated by the power transmitting controller  210 . 
     The series resonance converter  230  switches the direct current power supplied from the power charging unit  100  to generate an alternating current power in response to the PWM driving signal amplified by the driving driver  220 , and outputs the generated alternating current power to the power transmitting coil  240  to wirelessly transmit the power to the power receiving device. 
     The signal receiving unit  250  receives the ID signal and the charging status signal transmitted from the power receiving device through the power transmitting coil  240  to output the received ID signal and charging status signal to the power transmitting controller  210 . 
     The signal transmitting unit  260  transmits the ID request signal generated by the power transmitting controller  210  to the power receiving device through the power transmitting coil  240 . 
     According to the embodiment of the wireless power transmitting device of the present invention having the aforementioned configuration, when the alternating current power is input from the outside through the power plug P, the alternating/direct current converter  110  of the power storage unit  100  converts the alternating current power into the direct current power, and outputs the converted direct current power to the charging unit  120 . 
     The power transmitting controller  210  of the power transmitting unit  200  monitors the charging unit  120  to determine whether or not the direct current power is input from the alternating/direct current converter  110 , and when the direct current power is input, the power transmitting controller  210  controls the charging unit  120  to charge the battery  130  with the direct current power. 
     Furthermore, the power transmitting controller  210  receives the power charging information from the charging unit  120  to determine a power charging status of the battery  130 . When it is determined that the power charging of the battery  130  is completed, the power transmitting controller  210  controls the charging unit  120  to stop the power charging such that the battery  130  is not overcharged. 
     As described above, the power charged in the battery  130  is supplied to the power transmitting unit  200  as the operating power. 
     Meanwhile, in order for the power transmitting controller  210  of the power transmitting unit  200  to wirelessly transmit the power to the power receiving device, it is necessary to determine whether or not the power receiving device is placed on the power transmitting coil  240 . 
     To achieve this, the power transmitting controller  210  generates a load detecting driving signal for detecting whether or not a load of the power transmitting coil  240  is changed. The load detecting driving signal is amplified by the driving driver  220  to be input to the series resonance converter  230 . 
     The series resonance converter  230  switches the operating power supplied from the battery  130  to generate the alternating current power in response to the load detecting driving signal, and the generated alternating current power is applied to the power transmitting coil  240 . 
     Here, the load detecting driving signal has a high frequency of, for example, about 180 kHz which does not cause resonance in the power transmitting coil  240 . 
     Accordingly, the series resonance converter  230  switches the direct current power to generate the alternating current power in response to the load detecting driving signal, and even though the generated alternating current power is applied to the power transmitting coil  240 , since the resonance does not occur in the power transmitting coil  240 , power consumption is very low, and the alternating current power is rarely transmitted in a wireless manner. 
     In this state, the signal receiving unit  250  receives a signal of the power transmitting coil  240 , and outputs the received signal to the power transmitting controller  210 . The power transmitting controller  210  determines whether or not the load is changed by using frequency of the received signal input from the signal receiving unit  250 . 
     That is, when the load is not placed on the power transmitting coil  240 , the frequency of the alternating current power applied to the power transmitting coil  240  is rarely changed. 
     However, when the load is placed on the power transmitting coil  240 , an impedance is changed between the power transmitting coil  240  and the load, and the frequency of the alternating current power applied to the power transmitting coil  240  is changed depending on the change of the impedance. 
     The power transmitting controller  210  determines whether or not the frequency of the signal input from the signal receiving unit  250  is changed, and when the frequency is changed, it is determined that the load such as the power receiving device is placed on the power transmitting coil  240 . 
     That is, when the frequency of the signal input from the signal receiving unit  250  and the frequency of the load detecting driving signal are different from each other, the power transmitting controller  210  determines that the load is placed on the power transmitting coil  240 . 
     When it is determined that the load is placed on the power transmitting coil  240 , the power transmitting controller  210  needs to determine whether or not the load is the power receiving device. 
     To achieve this, the power transmitting controller  210  generates the ID request signal for requesting the ID signal of the power receiving device, and the generated ID request signal is transmitted to the load through the signal transmitting unit  260  and the power transmitting coil  240 . 
     Moreover, the power transmitting controller  210  receives the signal of the signal receiving unit  250  to determine whether or not the ID signal is received. 
     That is, when the load placed on the power transmitting coil  240  is the power receiving device, the power receiving device transmits the ID signal in response to the ID request signal. The ID signal transmitted from the power receiving device is received by the signal receiving unit  250  through the power transmitting coil  240  to be output to the power transmitting controller  210 , and the power transmitting controller  210  receives the signal of the signal receiving unit  250  to determine whether or not the ID signal is received. 
     When the ID signal is received, the power transmitting controller  210  determines that the load placed on the power transmitting coil  240  is the power receiving device. The power transmitting controller  210  generates the PWM driving signal for wirelessly transmitting the power, and the generated PWM driving signal is amplified by the driving driver  220  and is input to the series resonance converter  230 . 
     The series resonance converter  230  switches the direct current power of the battery  130  to generate the alternating current power in response to the PWM driving signal, and the generated alternating power is applied to the power transmitting coil  240 . 
     Here, the power transmitting coil  240  is designed to cause the resonance in a frequency of 100 kHz, for example, and the power transmitting controller  210  generates the PWM driving signal having a frequency of 100 kHz. 
     The series resonance converter  230  switches the direct current power to generate the alternating current power of 100 kHz in response to the PWM driving signal of 100 kHz, and the generated alternating current power of 100 kHz is applied to the power transmitting coil  240 . Thus, the power transmitting coil  240  causes the resonance by the alternating current power of 100 kHz. 
     When the resonance occurs in the power transmitting coil  240 , a large amount of current flows to the power transmitting coil  240  to allow the alternating current power to be wirelessly transmitted to the power receiving device. 
     In this state, the power receiving device detects the power charging status to generate the charging status signal, and transmits the generated charging status signal. The power transmitting controller  210  receives the charging status signal received by the signal receiving unit  250  to determine whether or not the power receiving device is overheated or the power charging of the power receiving device is completed. 
     When it is determined that the power receiving device is overheated, the power transmitting controller  210  adjusts the frequency of the PWM control signal. That is, the power transmitting controller  210  generates the PWM control signal having a frequency which is slightly deviated from a resonance frequency of the power transmitting coil  240 . 
     As the power transmitting controller  210  adjusts the frequency of the PWM control signal, the alternating current power applied to the power transmitting coil  240  is slightly deviated from a resonance point of the power transmitting coil  240 . Thus, a magnitude of the power that is wirelessly transmitted to the power receiving device from the power transmitting coil  240  is decreased, so that the power receiving device is prevented from being overheated. 
     In addition, when it is determined that the power charging of the power receiving device is completed by using the charging status signal, the power transmitting controller  210  does not generate the PWM driving signal, and ends the operation of wirelessly transmitting the power to the power receiving device. 
     According to the one embodiment of the wireless power transmitting device of the present invention, the power charging unit  100  and the power transmitting unit  200  may be respectively provided in separate cases, as illustrated in  FIG. 2A , and the power charging unit  100  converts the alternating current power input through the power plug P into the direct current power to charge the battery. Further, the power charging unit  100  and the power transmitting unit  200  may be connected to each other by a cable C to allow the direct current power charged in the power charging unit  100  to be supplied to the power transmitting unit  200 . 
     In this case, a user simply can carry the wireless power transmitting device while separating the power charging unit  100  from the power transmitting unit  200 , and use the wireless power transmitting device while connecting the power charging unit  100  to the power transmitting unit  200  by the cable C when charging the power receiving unit with the power. 
     According to an alternative embodiment of the wireless power transmitting device of the present invention, the power charging unit  100  and the power transmitting unit  200  may be integrally provided in a single case, as illustrated in  FIG. 2B . 
     Moreover, according to an alternative embodiment of the wireless power transmitting device of the present invention, the power charging unit  100  and the power transmitting unit  200  may be separated from each other and slidably combined with each other, as illustrated in  FIG. 2C . In addition, when the power charging unit  100  and the power transmitting unit  200  are slidably combined, the power charging unit and the power transmitting unit may be connected through a contact point (not illustrated in the drawing) to allow the power charging unit  100  to supply the operating power to the power transmitting unit  200 . 
     Similar to the embodiment depicted in  FIG. 2A , the user can simply carry the wireless power transmitting device while separating the power charging unit  100  from the power transmitting unit  200 , and use the wireless power transmitting device while slidably combining the power charging unit  100  and the power transmitting unit  200  when charging the power receiving device with the power. 
       FIG. 3  is a signal flowchart illustrating an operation of the power transmitting controller according to one embodiment of a method for wirelessly transmitting a power of the present invention. Referring to  FIG. 3 , the power transmitting controller  210  receives the signal of the charging unit  120  (S 300 ). Further, the power transmitting controller  210  determines whether or not the direct current power is input to the charging unit  120  from the alternating/direct current converter  110  by using the signal of the charging unit  120  (S 302 ). 
     When it is determined that the direct current power is input to the charging unit  120  from the alternating/direct current converter  110 , the power transmitting controller  210  controls the charging unit  120  to charge the battery  130  with the direct current power (S 304 ), and determines whether or not the charging of the battery  130  is completed (S 306 ). 
     As the determining result, when the charging of the battery  130  is not completed, the power transmitting controller  210  is returned to the operation S 302  to repeatedly perform the operation of controlling the charging unit  120  to charge the battery  130  with the direct current power input from the alternating/direct current converter  110  and determining whether or not the charging of the battery  130  is completed. 
     In this state, when the charging of the battery  130  is completed, the power transmitting controller  210  controls the charging unit  120  to stop the charging of the battery  130  by the direct current power (S 308 ) such that the battery  130  is not overcharged. 
     In addition, in the operation S 302 , when the direct current power is not input to the charging unit  120  from the alternating/direct current converter  110 , the power transmitting controller  210  performs a power transmitting operation of wirelessly transmitting the power to the power receiving device (S 310 ). 
     In the above embodiments of the present invention, it has been described that the operation of charging the battery  130  with the power and the operation of wirelessly transmitting the power through the power transmitting coil  240  are separately performed by the power transmitting controller  210 . 
     In implementing the present invention, the operation of charging the battery  130  with the power and the operation of wirelessly transmitting the power through the power transmitting coil  240  may be simultaneously performed by the power transmitting controller  210 . 
     As illustrated in  FIG. 4 , in the power transmitting operation, the power transmitting controller  210  generates the load detecting driving signal for detecting the change of the load (S 400 ). 
     The load detecting driving signal generated by the power transmitting controller  210  is amplified by the driving driver  220  and is input to the series resonance converter  230 . The series resonance converter  230  switches the direct current power of the battery  130  to generate the alternating current power in response to the load detecting driving signal, and the generated alternating current power is applied to the power transmitting coil  240 . 
     In such a state, the signal receiving unit  250  receives the signal of the power transmitting coil  240 , and outputs the received signal to the power transmitting controller  210 . 
     The power transmitting controller  210  detects the frequency of the signal input from the signal receiving unit  250  to determine whether or not the load is changed (S 402 ). 
     As the determining result, when the load is not changed, the power transmitting controller  210  is returned to the operation S 400  to repeatedly perform the operation of generating the load detecting driving signal for detecting the change of the load and detecting the frequency of the signal received by the signal receiving unit  250  to determine whether or not the load is changed. 
     Further, when the change of the load is detected in the operation S 402 , the power transmitting controller  210  generates the ID request signal for requesting the ID signal of the power receiving device, and the generated ID request signal is transmitted to the power receiving device through the signal transmitting unit  260  and the power transmitting coil  240  (S 404 ). 
     In such a state, the power transmitting controller  210  receives the received signal of the signal receiving unit  250  to determine whether or not the ID signal is received from the power receiving device (S 406 ). 
     As the determining result, when the ID signal is not received, the power transmitting controller  210  determines whether or not a preset time elapses (S 408 ). 
     When the preset time does not elapse, the power transmitting controller is returned to the operation S 406  to repeatedly perform the operation of determining whether or not the ID signal is received from the power receiving device. 
     Furthermore, even though the preset time elapses, when the ID signal is not received, since a foreign substance other than the power receiving device is placed on the power transmitting coil  240 , the power transmitting controller  210  is returned to the operation S 400  to repeatedly perform the operation of generating the load detecting driving signal. 
     Moreover, when the ID signal is received before the preset time elapses, the power transmitting controller  210  determines that the power receiving device is placed on the power transmitting coil  240 , and generates the PWM driving signal for wirelessly transmitting the power (S 410 ). 
     The PWM driving signal generated by the power transmitting controller  210  is amplified by the driving driver  220 , and is input to the series resonance converter  230  to generate the alternating current power, and the generated alternating current power is applied to the power transmitting coil  240  to wirelessly transmit the power to the power receiving device. 
     In this state, the power transmitting controller  210  receives the charging status signal transmitted by the power receiving device through the signal receiving unit  250  (S 412 ), and analyzes the received charging status signal to determine whether or not the power receiving device is overheated (S 414 ). 
     As the determining result, when the power receiving device is overheated, the power transmitting controller  210  adjusts the frequency of the PWM driving signal to prevent the overheating (S 416 ). 
     Furthermore, the power transmitting controller  210  determines whether or not the power charging of the power receiving device is completed by using the charging status signal (S 418 ). 
     When the power charging of the power receiving device is not completed, the power transmitting controller  210  is returned to the operation S 412  to perform the operation of receiving the charging status signal transmitted by the power receiving device and determining whether or not the power charging of the power receiving device is completed using the received charging status signal. When the power charging of the power receiving device is completed, the power transmitting controller ends the operation of transmitting the power. 
       FIG. 5  is a block diagram illustrating a configuration of another embodiment of the wireless power transmitting device of the present invention. The another embodiment of the wireless power transmitting device of the present invention is different from aforementioned embodiments in that the power storage unit  100  may further include a power supply switch  140 , a power receiving coil  150 , a rectifier  160 , a first signal receiving unit  170 , and a first signal transmitting unit  180 . 
     The power supply switch  140  is provided between the alternating/direct current converter  110  and the charging unit  120 , and is switched under the control of the power transmitting controller  210  to input or block the direct current power output from the alternating/direct current converter  110  to the charging unit  120 . 
     The power receiving coil  150  receives the alternating current power that is wirelessly transmitted from the outside. 
     The rectifier  160  converts the alternating current power received by the power receiving coil  150  into the direct current power to output the converted direct current power to the charging unit  120 . 
     The first signal receiving unit  170  receives the ID request signal through the power receiving coil  150  to output the received ID request signal to the power transmitting controller  210 . 
     The first signal transmitting unit  180  transmits the ID signal and the charging status signal generated by the power transmitting controller  210  to the outside through the power receiving coil  150 . 
     In the another embodiment of the wireless power transmitting device of the present invention having the aforementioned configuration, the power transmitting controller  210  controls the power supply switch  140  to connect. 
     In this state, the alternating current power input from the outside through the power plug P is converted into the direct current power by the alternating/direct current converter  110 , and the converted direct current power is provided to the charging unit  120  through the power supply switch  140 . 
     The power transmitting controller  210  receives the signal of the charging unit  120  to determine whether or not the direct current power is input from the alternating/direct current converter  110 , and when the direct current power is input, the power transmitting controller controls the charging unit  120  to charge the battery  130  with the direct current power. 
     Furthermore, the power transmitting controller  210  receives the received signal of the first signal receiving unit  170  to determine whether or not the ID request signal is received. 
     That is, when an external wireless power transmitting device (not illustrated in the drawing) wirelessly transmits a power signal, the ID request signal is firstly transmitted, and the transmitted ID request signal is received by the first signal receiving unit  170  through the power receiving coil  150  to be input to the power transmitting controller  210 . The power transmitting controller  210  receives the received signal of the first receiving unit  170  to determine whether or not the ID request signal is received. 
     When the ID request signal is received, the power transmitting controller  210  opens the power supply switch  140  to block the direct current power output from the alternating/direct current converter  110  not to be input to the charging unit  120 . 
     Moreover, the power transmitting controller  210  generates a unique ID signal assigned to the power transmitting controller, and the generated ID signal is transmitted to the external wireless power transmitting device through the first signal transmitting unit  180  and the power receiving coil  150 . 
     In this state, when the external wireless power transmitting device wirelessly transmits the power signal, the power receiving coil  150  receives the transmitted power signal, and the rectifier  160  converts the received power signal into the direct current power to output the converted direct current power to the charging unit  120 . 
     In such a state, the power transmitting controller  120  receives the signal of the charging unit  120  to check whether or not the direct current power is input from the rectifier  160  to the charging unit  120 . As the checking result, when the direct current power is input to the charging unit  120 , the power transmitting controller  210  controls the charging unit  120  to charge the battery  130  with the direct current power. 
     In addition, the power transmitting controller  210  receives the signal of the charging unit  120  to determine the power charging status of the battery  130 , and generates the charging status signal including the determined power charging status. The generated charging status signal is transmitted to the outside through the first signal transmitting unit  180  and the power receiving coil  150 . 
     Further, when the power charging of the battery  130  is completed, the power transmitting controller  210  generates the charging status signal indicating that the power charging is completed, and the generated charging status signal is transmitted to the outside through the first signal transmitting unit  180  and the power receiving coil  150 . 
     Furthermore, the power transmitting controller  210  controls the charging unit  120  to stop the charging of the battery  130  with the direct current power such that the battery  130  is not overcharged. 
     Meanwhile, the operation of wirelessly transmitting the power by the power transmitting unit  200  through the power transmitting coil  240  to the external power receiving device is the same as that in the aforementioned embodiments, and, thus, detailed description thereof will not be repeated. 
     Similarly to the aforementioned embodiments, in the another embodiment of the wireless transmitting device of the present invention, the power charging unit  100  and the power transmitting unit  200  may be separated from each other, as illustrated in  FIG. 6A , and the power charging unit  100  converts the alternating current power input through the power plug P or the power receiving coil  150  into the direct current power to charge the battery. Furthermore, the power charging unit  100  and the power transmitting unit  200  may be connected by the cable C to allow the direct current power charged in the power charging unit  100  to be supplied to the power transmitting unit  200 . 
     In addition, according to another alternative embodiment of the wireless power transmitting device of the present invention, the power charging unit  100  and the power transmitting unit  200  may be integrally installed in a single case, as illustrated in  FIG. 6B . 
     In another alternative embodiment of the wireless power transmitting device of the present invention, the power charging unit  100  and the power transmitting unit  200  may be separated, and slidably combined with each other, as illustrated in  FIG. 6C . Moreover, when the power charging unit  100  and the power transmitting unit  200  are slidably combined, the power charging unit and the power transmitting unit may be connected by the contact point (not illustrated in the drawing) to allow the power charging unit  100  to supply the operating power to the power transmitting unit  200 . 
     In the another embodiment of the present invention, it has been described that the operation of charging the battery  130  with the power and the operation of wirelessly transmitting the power through the power transmitting coil  240  have been separately performed by the power transmitting controller  210 . 
     In implementing the present invention, the operation of charging the battery  130  with the power and the operation of wirelessly transmitting the power through the power transmitting coil  240  may be simultaneously performed by the power transmitting controller  210 . 
       FIG. 7  is a signal flowchart illustrating an operation of the power transmitting controller  210  according to another embodiment of the method for wirelessly transmitting a power of the present invention. Referring to  FIG. 7 , the power transmitting controller  210  firstly connects the power supply switch  140  (S 700 ). 
     The alternating current power input from the outside through the power plug P is converted into the direct current power by the alternating/direct current converter  110 , and the converted direct current power is input to the charging unit  120  through the power supply switch  140 . 
     In this state, the power transmitting controller  210  receives the signal of the charging unit  120  (S 702 ), and determines whether or not the direct current power is input by using the received signal of the charging unit  120  (S 704 ). 
     When it is determined that the direct current power is input, the power transmitting controller  210  controls the charging unit  120  to charge the battery  130  with the direct current power (S 706 ). 
     Further, the power transmitting controller  210  determines whether or not the charging of the battery  130  with the direct current power is completed (S 708 ), and ends the operation of charging the battery  130  with the direct current power when the charging is completed. 
     Meanwhile, when the direct current power is not input in the operation S 704 , or when the charging is not completed in the operation S 708 , the power transmitting controller  210  receives the received signal from the first signal receiving unit  170  to determine whether or not the ID request signal is received (S 710 ). 
     When it is determined that the ID request signal is not received, the power transmitting controller  210  performs the power transmitting operation (S 712 ). 
     Here, the power transmitting operation of the operation S 712  is the same as that in  FIG. 4 , and, thus, detailed description thereof will not be repeated. 
     When it is determined that the ID request signal is received in the operation S 710 , the power transmitting controller  210  opens the power supply switch  140  to block the direct current power output from the alternating/direct current converter  140  not to be input to the charging unit  120  (S 714 ). 
     Further, the power transmitting controller  210  generates the unique ID signal, and the generated ID signal is transmitted to the outside through the first signal transmitting unit  180  and the power receiving coil  150  (S 716 ). 
     In this state, the power transmitting controller  210  receives the signal of the charging unit  120  (S 718 ), and determines whether the direct current power is input by using the received signal of the charging unit  120  (S 720 ). 
     That is, when the external wireless power transmitting device wirelessly transmits the power signal, the power receiving coil  150  receives the transmitted power signal, and the rectifier  160  converts the received power signal into the direct current power to output the converted direct current power to the charging unit  120 . The power transmitting controller  210  receives the signal of the charging unit  120  to determine whether or not the direct current power is input to the charging unit  120  from the rectifier  160 . 
     When it is determined that the direct current power is input to the charging unit  120 , the power transmitting controller  210  controls the charging unit  120  to charge the battery  130  with the direct current power (S 722 ). 
     Furthermore, the power transmitting controller  210  receives the signal of the charging unit  120  to determine the power charging status of the battery  130  (S 724 ), and determines whether or not the power charging of the battery  130  is completed (S 726 ). 
     When the power charging of the battery  130  is not completed; the power transmitting controller  210  generates the charging status signal including the power charging status of the battery  130 . The generated charging status signal is transmitted to the outside through the first signal transmitting unit  180  and the power receiving coil  150  (S 728 ), and the power transmitting controller is returned to the operation S 724  to repeatedly perform the operation of determining the power charging status of the battery  130 . 
     In this state, when the power charging of the battery  130  is completed, the power transmitting controller  210  generates a charging status signal including power charging completion information of the battery  130 , and the generated charging status signal is transmitted to the outside through the power receiving coil  150  (S 730 ). 
     Moreover, the power transmitting controller  210  controls the charging unit  120  not to charge the battery  130  with the direct current power (S 732 ), and ends the power charging operation. 
       FIG. 8  is a block diagram illustrating a configuration of still another embodiment of the wireless power transmitting device of the present invention. Referring to  FIG. 8 , in the still another embodiment of the present invention, transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4  that are controlled by the power transmitting controller  210  are provided between the rectifier  160  and the series resonance converter  230  and between the rectifier  160  and the power transmitting coil  240 , so that the power transmitting coil  240  is connected to the rectifier  160  or the series resonance converter  230  according to the switching of the transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4 . 
     That is, by connecting the power transmitting coils  240  to operation terminals of the transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4 , one fixation terminals a1, a2, a3 and a4 of the transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4  are connected to an output terminal of the series resonance converter  230 , and the other fixation terminals b1, b2, b3 and b4 of the transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4  are connected to an input terminal of the rectifier  160 . 
     In the still another embodiment of the wireless power transmitting device of the present invention having the aforementioned configuration, when the battery  130  is charged with the power, the power transmitting controller  210  firstly connects the power supply switch  140 . The alternating current power input from the outside through the external power plug P is converted into the direct current power by the alternating/direct current converter  110 , and is input to the charging unit  120  through the power supply switch  140 . 
     In this state, the power transmitting controller  210  receives the signal of the charging unit  120  to determine whether or not the direct current power is input, and controls the charging unit  120  to charge the battery  130  with the direct current power when it is determined that the direct current power is input. 
     Moreover, the power transmitting controller  210  receives the received signal of the signal receiving unit  250  to determine whether or not the ID request signal is received. 
     When the ID request signal is received, the power transmitting controller  210  firstly opens the power supply switch  140  to block the direct current output from the alternating/direct current converter  110  not to be input to the charging unit  120 . 
     In addition, the power transmitting controller  210  generates the ID signal, and the generated ID signal is transmitted through the signal transmitting unit  260  and the power transmitting coil  240 . Further, the power transmitting controller  210  controls the transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4  to connect the operation terminals to the other fixation terminals b1, b2, b3 and b4. 
     In such a state, when the external wireless power transmitting device wirelessly transmits the power, the transmitted power is received by the power transmitting coil  240 , the received power is converted into the direct current power by the rectifier  160 , and then the converted power is output to the charging unit  120 . 
     Moreover, the power transmitting controller  210  receives the signal of the charging unit  120  to check whether or not the direct current power is input to the charging unit  120  from the rectifier  160 , and controls the charging unit  120  to charge the battery  130  with the direct current power when it is checked that the direct current power is input. 
     In addition, the power transmitting controller  210  determines the power charging status of the battery  130  by using the signal of the charging unit  120 , and generates the charging status signal including the determined power charging status. The generated charging status signal is transmitted to the outside through the signal transmitting unit  260  and the power transmitting coil  240 . 
     Meanwhile, when the power transmitting unit  200  wirelessly transmits the power to the outside, the power transmitting controller  210  controls the transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4  to connect the operation terminals to the one fixation terminals a1, a2, a3 and a4. 
     As stated above, the operation of connecting the operation terminals of the transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4  to the one fixation terminals a1, a2, a3 and a4 and then wirelessly transmitting the power to the outside is the same as that in the aforementioned embodiments, and, thus, detailed description thereof will not be repeated. 
     Similarly to the aforementioned embodiments, in the still another embodiment of the wireless power transmitting device of the present invention, the power charging unit  100  and the power transmitting unit  200  may be separated from each other, as illustrated in  FIG. 9A , and the power charging unit  100  converts the alternating current power input through the power plug P or the power receiving coil  240  into the direct current power to charge the battery. Further, the power charging unit  100  and the power transmitting unit  200  may be connected by the cable C to supply the direct current power charged in the power charging unit  100  to the power transmitting unit  200 . 
     Furthermore, in still another alternative embodiment of the wireless power transmitting device of the present invention, the power charging unit  100  and the power transmitting unit  200  may be integrally provided in a single case, as illustrated in  FIG. 9B . 
     Moreover, in still another alternative embodiment of the wireless power transmitting device of the present invention, the power charging unit  100  and the power transmitting unit  200  may be separated from each other, and slidably combined with each other, as illustrated in  FIG. 9C . In addition, when the power charging unit  100  and the power transmitting unit  200  are slidably combined, the power charging unit and the power transmitting unit may be connected through a contact point (not illustrated in the drawing) to allow the power charging unit  100  to supply the operating power to the power transmitting unit  200 . 
       FIG. 10  is a signal flowchart illustrating an operation of the power transmitting controller according to the still another embodiment of the method for wirelessly transmitting a power the present invention. Referring to  FIG. 10 , the power transmitting controller  210  firstly connects the power supply switch  140  (S 1000 ). 
     The direct current power output from the alternating/direct current converter  110  is input to the charging unit  120  through the power supply switch  140 . 
     Furthermore, the power transmitting controller  210  receives the signal of the charging unit  120  (S 1002 ), and determines whether or not the direct current power is input by using the received signal of the charging unit  120  (S 1004 ). 
     When it is determined that the direct current power is input, the power transmitting controller  210  controls the charging unit  120  to charge the battery  130  with the direct current power (S 1006 ). 
     In this state, the power transmitting controller  210  determines whether or not the charging of the battery  130  with the direct current power is completed (S 1008 ), and ends the operation of charging the battery  130  with the direct current power when the charging is completed. 
     Meanwhile, when the direct current power is not input in the operation S 1004 , or when the charging is not completed in the operation S 1008 , the power transmitting controller  210  receives the received signal of the signal receiving unit  250  to determine whether or not the ID request signal is received (S 1010 ). 
     When it is determined that the ID request signal is received, the power transmitting controller  210  opens the power supply switch  140  to block the direct current power output from the alternating/direct current converter  140  not to be input to the charging unit  120  (S 1012 ). Further, the power transmitting controller  210  generates the unique ID signal, and the generated ID signal is transmitted to the outside through the signal transmitting unit  260  and the power transmitting coil  240  (S 1014 ). 
     Moreover, the power transmitting controller  210  controls the transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4  to connect the operation terminals to the other fixation terminals b1, b2, b3 and b4 (S 1016 ), receives the signal of the charging unit  120  (S 1018 ), and then determines whether or not the direct current power is input by using the received signal of the charging unit  120  (S 1020 ). 
     When the direct current power is input to the charging unit  120 , the power transmitting controller  210  controls the charging unit  120  to charge the battery  130  with the direct current power (S 1022 ). 
     In addition, the power transmitting controller  210  receives the signal of the charging unit  120  to determine the power charging status of the battery  130  (S 1024 ), and determines whether or not the power charging of the battery  130  is completed (S 1026 ). 
     When the power charging of the battery  130  is not completed, the power transmitting controller  210  controls the first signal transmitting unit  180  to generate the charging status signal including the current power charging status of the battery  130 , and the generated charging status signal is transmitted to the outside through the power transmitting coil  240  (S 1028 ). The power transmitting controller is returned to the operation S 1024  to repeatedly perform the operation of determining the power charging status of the battery  130 . 
     In this state, when the power charging of the battery  130  is completed, the power transmitting controller  210  generates the charging status signal including the power charging completion information of the battery  130 , and the generated charging status signal is transmitted to the outside through the power transmitting coil  240  (S 1030 ). 
     Further, the power transmitting controller  210  controls the charging unit  120  not to charge the battery  130  with the power (S 1032 ), and ends the power charging operation. 
     Meanwhile, when the ID request signal is not received in the operation S 1010 , the power transmitting controller  210  controls the transmission/reception switches  270 - 1 ,  270 - 2 ,  270 - 3  and  270 - 4  to connect the operation terminals to the one fixation terminals a1, a2, a3 and a4 (S 1034 ), and performs the power transmitting operation (S 1036 ). 
     Here, the operation of wirelessly transmitting the power by the power transmitting unit  200  is the same as that in the aforementioned embodiments, and, thus, detailed operation description thereof will not be repeated. 
     In the still another embodiment of the present invention, it has been described that the operation of charging the battery  130  with the power and the operation of wirelessly transmitting the power through the power transmitting coil  240  have been separately performed by the power transmitting controller  210 . 
     However, when the battery  130  is charged with the direct current power by using the alternating current power input through the power plug P, the operation of charging the battery  130  with the power and the operation of wirelessly transmitting through the power transmitting coil  240  may be simultaneously performed by the power transmitting controller  210 . 
     As described above, the present invention has been described in detail in connection with the representative embodiments, but it should be understood to those skilled in the art that the aforementioned embodiments can be modified in various manners without departing from the scope of the present invention. 
     Therefore, the scope of the present invention is not limited to the aforementioned embodiments, and should be decided by the appended claims and their equivalents.