KR20170005589A - Apparatus for transmitting wireless power and system for transmitting wireless power - Google Patents

Abstract

A wireless power transmission apparatus according to an embodiment of the present invention is a wireless power transmission apparatus according to an embodiment of the present invention includes a transmission coil unit including a plurality of transmission coils for transmitting AC power to a wireless power reception apparatus, And a transmitting side controller for determining the size of the wireless power receiving device based on the unique information (RXID) received from the receiving device and selecting one of the plurality of transmitting coils according to the size of the wireless power receiving device.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a wireless power transmission apparatus and a wireless power transmission system,

The present invention relates to a wireless power transmission apparatus and a wireless power transmission system.

Recently, as the information and communication technology rapidly develops, a ubiquitous society based on information and communication technology is being made. In order for information communication devices to be connected anytime and anywhere, sensors equipped with a computer chip having a communication function must be installed in all facilities of the society. Therefore, power supply problems of these devices and sensors are becoming a new challenge. In addition, mobile devices such as Bluetooth headsets and iPods, as well as mobile phones, have been rapidly increasing in number, and charging the battery has required users time and effort. As a way to solve this problem, wireless power transmission technology has recently attracted attention.

The wireless power transmission technology (wireless power transmission or wireless energy transfer) is a technology to transmit electric energy from the transmitter to the receiver wirelessly using the induction principle of the magnetic field. In the 1800s, electric motor or transformer Thereafter, a method of transmitting electric energy by radiating an electromagnetic wave such as a radio wave or a laser was tried. Our electric toothbrushes and some wireless shavers are actually charged with electromagnetic induction.

Until now, energy transmission using radio has been largely divided into a magnetic induction system, a magnetic resonance system, and a power transmission system using a short wavelength radio frequency.

In the magnetic induction method, when two coils are adjacent to each other and a current is supplied to one coil, a magnetic flux generated at this time causes an electromotive force to the other coils. As a technology, . The magnetic induction method has the disadvantage that it can transmit power of up to several hundred kilowatts (kW) and the efficiency is high, but the maximum transmission distance is 1 centimeter (cm) or less, so it is usually adjacent to the charger or the floor.

The self-resonance method is characterized by using an electric field or a magnetic field instead of using electromagnetic waves or currents. The self-resonance method is advantageous in that it is safe to other electronic devices or human body since it is hardly influenced by the electromagnetic wave problem. On the other hand, it can be used only at a limited distance and space, and has a disadvantage that energy transfer efficiency is somewhat low.

Short wavelength wireless power transmission - simply, the RF method - takes advantage of the fact that energy can be transmitted and received directly in the form of RadioWaves. This technology is a RF power transmission system using a rectenna. Rectena is a combination of an antenna and a rectifier, which means a device that converts RF power directly into direct current power. That is, the RF method is a technique of converting an AC radio wave into DC and using it. Recently, as the efficiency has improved, commercialization has been actively researched.

Wireless power transmission technology can be applied not only to mobile, but also to various industries such as IT, railroad, and household appliance industry.

In recent years, the development of a transmitter having a combination of a magnetic induction method and a magnetic resonance method has been actively developed. This is because power can be supplied to the receiving unit irrespective of the type of the power supply system of the receiving unit.

Meanwhile, a wireless power transmission apparatus including a plurality of coils is provided according to various kinds of wireless power receiving apparatuses. However, there is a problem that a receiving apparatus requiring less power ruptures by receiving high power.

An object of the present invention is to provide a wireless power transmission apparatus in which a plurality of transmission coils for selectively transmitting power are disposed according to the size of a wireless power receiving apparatus.

The present invention aims to provide a method for the wireless power transmission apparatus to identify a wireless power reception apparatus.

A wireless power transmission apparatus according to an embodiment of the present invention includes a transmission coil unit including a plurality of transmission coils for transmitting AC power to a wireless power reception apparatus, and a transmission coil unit for transmitting, based on the unique information (RXID) received from the wireless power reception apparatus And a transmitting side controller for determining the size of the wireless power receiving device and selecting one of the plurality of transmitting coils according to the size of the wireless power receiving device.

A wireless power transmission system according to an embodiment includes the wireless power transmission apparatus and a wireless power reception apparatus that receives power from the wireless power transmission apparatus.

The present invention has the effect of selectively improving the transmission efficiency by selectively driving the transmission coil according to the size of the wireless power receiving apparatus.

In addition, a transmission coil according to the size of the wireless power receiving apparatus is selected to have a high coupling coefficient, thereby improving the transmission efficiency.

1 is a magnetic induction equivalent circuit.
2 is a self-resonant-type equivalent circuit.
3A and 3B are block diagrams showing a transmitter as one of sub-systems constituting a wireless power transmission system.
4 is a block diagram illustrating a receiving unit as one of the subsystems constituting the wireless power transmission system.
5 is a plan view showing a transmission coil part according to an embodiment of the present invention.
6 is a plan view showing a transmission coil according to another embodiment of the present invention.
7 is a plan view showing a transmitting coil part according to another embodiment of the present invention.
8 is a plan view showing a transmission coil according to another embodiment of the present invention.
9 and 10 are circuit diagrams illustrating a driving unit according to an embodiment of the present invention.
11 is a flowchart illustrating a charging method of a wireless power transmission apparatus according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a wireless power transmission system including a wireless power transmission apparatus having a function of wirelessly transmitting power and a wireless power reception apparatus wirelessly receiving power according to an embodiment of the present invention will be described in detail with reference to the drawings. The following embodiments are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention. Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the size and thickness of an apparatus may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification.

Embodiments may include a communication system that selectively uses various types of frequency bands from a low frequency (50 kHz) to a high frequency (15 MHz) for wireless power transmission and can exchange data and control signals for system control .

The embodiments can be applied to various industrial fields such as a mobile terminal industry using a battery or an electronic device required, a smart clock industry, a computer and notebook industry, a household appliance industry, an electric car industry, a medical device industry, and a robot industry .

Embodiments may consider a system capable of power transmission to one or more multiple devices using one or more transmission coils.

According to the embodiment, it is possible to solve the battery shortage problem in a mobile device such as a smart phone and a notebook. For example, when a wireless charging pad is placed on a table and a smart phone or a notebook is used on the table, the battery is automatically charged and can be used for a long time . In addition, by installing wireless charging pads in public places such as cafes, airports, taxis, offices, restaurants, etc., mobile devices manufacturers can charge various mobile devices regardless of charging terminals. In addition, when wireless power transmission technology is applied to household electrical appliances such as cleaners, electric fans, etc., there is no need to look for power cables and complex wires can be eliminated in the home, which can reduce wiring in buildings and increase the space utilization. In addition, it takes a lot of time to charge the electric car with the current household power, but if the high power is transmitted through the wireless power transmission technology, the charging time can be reduced. If the wireless charging facility is installed at the bottom of the parking lot, It is possible to solve the inconvenience of having to prepare.

The terms and abbreviations used in the examples are as follows.

Wireless Power Transfer System: A system that provides wireless power transmission within a magnetic field region

Wireless Power Transfer System-Charger: A device that provides wireless power transmission to a power receiver within a magnetic field area and manages the entire system.

Wireless Power Transfer System-Device: A device that is provided with a wireless power transmission from a power transmitter within a magnetic field area.

Charging Area: A region where actual wireless power transmission occurs within the magnetic field region, and may vary depending on the size, required power, and operating frequency of the application product.

Scattering parameter: The S parameter is the ratio of the input port to the output port in terms of the input voltage to the output voltage on the frequency distribution (Transmission S21) or the self reflection value of each input / output port, Reflection (S11, S22) of the reflected output.

Quality factor Q: The value of Q in resonance means the quality of frequency selection. The higher the Q value, the better the resonance characteristics. The Q value is expressed as the ratio of the energy stored in the resonator to the energy lost.

The principles of wireless power transmission include magnetic induction and self-resonance.

The magnetic induction method is a noncontact energy transfer technique in which an electromotive force is generated in the load inductor Ll via a magnetic flux generated when the source inductor Ls and the load inductor Ll are brought close to each other and a current is supplied to one of the source inductors Ls. to be. The self-resonance method combines two resonators to generate self-resonance by the natural frequency between the two resonators. By resonating at the same frequency and using the resonance technique to form an electric field and a magnetic field in the same wavelength range, Technology.

1 is a magnetic induction equivalent circuit.

Referring to FIG. 1, in a magnetic induction equivalent circuit, a wireless power transmission apparatus includes a source voltage Vs, a source resistance Rs, a source capacitor Cs for impedance matching, And the wireless power receiving device may be implemented as a load resistance Rl that is an equivalent resistance of the wireless power receiving device, a load capacitor Cl for impedance matching, And the magnetic coupling between the source coil Ls and the load coil Ll can be expressed by mutual inductance Msl.

In FIG. 1, the ratio S21 of the input voltage to the output voltage is obtained from the magnetic induction equivalent circuit consisting only of the coil without the source capacitor Cs and the load capacitor Cl for impedance matching, The power transmission condition satisfies Equation (1) below.

[Equation 1]

Ls / Rs = L1 / R1

The maximum power transmission is possible when the ratio of the inductance of the transmission coil Ls to the source resistance Rs and the ratio of the inductance of the load coil Ll to the load resistance Rl are equal to each other. Since there is no capacitor capable of compensating for reactance in a system in which there is only an inductance, the value of the self reflection value S11 of the input / output port can not be zero at the point where the maximum power is transmitted, and the mutual inductance Msl, The power transfer efficiency can vary greatly depending on the value. Therefore, the source capacitor Cs can be added to the wireless power transmission apparatus as a compensation capacitor for impedance matching, and the load capacitor Cl can be added to the wireless power reception apparatus. The compensation capacitors Cs and Cl may be connected in series or in parallel to the receiving coil Ls and the load coil Ll, respectively. Further, for the impedance matching, each of the wireless power transmitting apparatus and the wireless power receiving apparatus may be further provided with a passive element such as an additional capacitor and an inductor as well as a compensation capacitor.

2 is a self-resonant-type equivalent circuit.

2, in a self-resonant type equivalent circuit, a radio power transmission apparatus includes a source coil constituting a closed circuit by a series connection of a source voltage Vs, a source resistance Rs and a source inductor Ls, Side resonant coil constituting a closed circuit by a series connection of the side resonant inductor L1 and the transmission side resonant capacitor C1 and the wireless power receiving apparatus is implemented by a load resistor R1 and a load inductor L1, Side resonance coil constituting a closed circuit by a series connection of a load coil constituting a closed circuit by a series connection of the resonance inductor L2 and a resonance inductor L2 on the reception side and a resonance capacitor C2 on the reception side, The load inductor L1 and the load side resonance inductor L2 are magnetically coupled to each other by a coupling coefficient of K23 and the transmission side inductor L1 is magnetically coupled to the transmission side inductor L1 ) And the receiving-side resonance inductor (L2) And is magnetically coupled to the coupling coefficient. In the equivalent circuit of another embodiment, the source coil and / or the load coil may be omitted and only the transmission-side resonance coil and the reception-side resonance coil may be formed.

When the resonance frequencies of the two resonators are the same, most of the energy of the resonator of the wireless power transmission apparatus is transmitted to the resonator of the wireless power receiving apparatus so that the power transmission efficiency can be improved, and the efficiency in the self- It is better when the equation (2) is satisfied.

&Quot; (2) "

k / Γ >> 1 (k is the coupling coefficient, Γ attenuation factor)

In order to increase the efficiency in the self-resonant mode, an element for impedance matching can be added, and the impedance matching element can be a passive element such as an inductor and a capacitor.

Based on such a wireless power transmission principle, a wireless power transmission system for transmitting power by a magnetic induction method or a self resonance method will be described.

<Wireless power transmission device>

FIGS. 3A and 3B are block diagrams illustrating a wireless power transmission apparatus as one of the sub-systems constituting the wireless power transmission system.

Referring to FIG. 3A, a wireless power transmission system according to an embodiment may include a wireless power transmission apparatus 1000 and a wireless power reception apparatus 2000 receiving wireless power from a wireless power transmission apparatus 1000. FIG. The wireless power transmission apparatus 1000 includes a power conversion unit 101 for converting an input AC signal into an AC signal and outputting the AC signal as an AC signal, and a magnetic field generator for generating a magnetic field based on the AC signal output from the power conversion unit 101, A resonance circuit section 102 for providing power to the wireless power receiving apparatus 2000 and a control section for controlling the power conversion of the power conversion section 101 and adjusting the amplitude and frequency of the output signal of the power conversion section 101, Voltage, and current information from the power conversion unit 101 and the resonance circuit unit 102 and performs wireless communication with the wireless power reception apparatus 2000. The wireless power reception apparatus 2000 performs impedance matching of the resonance circuit unit 102, And a control unit 103 that can control the operation of the apparatus. The power conversion unit 101 may include at least one of a power conversion unit that converts an AC signal to DC, a power conversion unit that outputs a DC by varying the level of the DC, and a power conversion unit that converts DC into AC . The resonance circuit unit 102 may include a coil and an impedance matching unit capable of resonating with the coil. The control unit 103 may include a sensing unit and a wireless communication unit for sensing impedance, voltage, and current information.

 3B, the wireless power transmission apparatus 1000 includes a transmitting side AC / DC converting unit 1100, a transmitting side DC / AC converting unit 1200, a transmitting side impedance matching unit 1300, A portion 1400 and a sender communication and control portion 1500. [

The transmitting side AC / DC converting unit 1100 is a power converting unit for converting an AC signal provided from the outside under the control of the transmitting side communication and control unit 1500 to a DC signal. The transmitting side AC / DC converting unit 1100 includes: May include a rectifier 1110 and a transmission side DC / DC converter 1120 as a subsystem. The rectifier 1110 converts a supplied AC signal into a DC signal. The rectifier 1110 may be a diode rectifier having a relatively high efficiency in high-frequency operation, a synchronous rectifier capable of one-chip operation, And a hybrid rectifier capable of saving space and having a high degree of freedom in dead time. However, the present invention is not limited to this, and can be applied to a system that converts AC to DC. The transmitting side DC / DC converting unit 1120 adjusts the level of the DC signal provided from the rectifier 1110 under the control of the transmitting side communication and control unit 1500. As an example of implementing the DC signal, A buck converter, a boost converter that boosts the level of the input signal, a buck-boost converter or a Cuk converter that can raise or lower the level of the input signal. Also, the transmission side DC / DC converter 1120 includes a switch element that performs a power conversion control function, an inductor and a capacitor that perform a power conversion medium function or an output voltage smoothing function, a voltage gain control function or an electrical isolation function (insulation function) And may have a function of removing a ripple component or a ripple component (AC component included in the DC signal) included in the input DC signal. The error between the command value of the output signal of the transmitting side DC / DC converting unit 1120 and the actual output value can be adjusted through the feedback method and can be performed by the transmitting side communication and control unit 1500 .

The transmission side DC / AC conversion unit 1200 converts the DC signal output from the transmission side AC / DC conversion unit 1100 into an AC signal under the control of the transmission side communication and control unit 1500 and outputs the converted AC signal frequency A half bridge inverter or a full bridge inverter is an example of implementing this system. In the wireless power transmission system, various amplifiers for converting direct current to alternating current can be applied. For example, class A, class B, class AB, class C, class E class F amplifier. The transmission side DC / AC conversion unit 1200 may include an oscillator for generating a frequency of an output signal and a power amplifier for amplifying an output signal.

The transmission-side impedance matching unit 1300 minimizes the reflected waves at points having different impedances to improve the signal flow. Since the two coils of the wireless power transmitting apparatus 1000 and the wireless power receiving apparatus 2000 are spatially separated and have a large leakage of magnetic field, the wireless power transmitting apparatus 1000 and the wireless power receiving apparatus 2000, The power transmission efficiency can be improved. The impedance matching unit 1300 may include an inductor, a capacitor, and a resistor. Under the control of the communication and control unit 1500, the inductance of the inductor, the capacitance of the capacitor, The impedance value can be adjusted. When the wireless power transmission system transmits power in a self-induction manner, the transmission-side impedance matching unit 1300 may have a series resonance structure or a parallel resonance structure, and may include a wireless power transmission apparatus 1000 and a wireless power reception apparatus 2000) can be increased to minimize the energy loss. When the wireless power transmission system transmits power in a self-resonant manner, the transmission-side impedance matching unit 1300 may determine that the distance between the wireless power transmission apparatus 1000 and the wireless power reception apparatus 2000 is changed or the metallic foreign matter FO ; Foreign Object), mutual influences by a plurality of devices, and the like, it is possible to make real-time correction of impedance matching according to a change in matching impedance on an energy transmission line due to a change in characteristics of a coil, Method, a matching method using a multi-antenna, a method using a multi-loop, and the like.

The transmitting coil 1400 may be implemented as a plurality of coils or a plurality of coils. If a plurality of transmitting coils 1400 are provided, they may be spaced apart from each other, The overlapping area can be determined in consideration of the deviation of the magnetic flux density. Also, when the transmission coil 1400 is manufactured, it can be manufactured in consideration of the internal resistance and the radiation resistance. If the resistance component is small, the quality factor can be increased and the transmission efficiency can be increased.

The communication and control unit 1500 may include a transmission side control unit 1510 and a transmission side communication unit 1520. The transmitting-side controller 1510 may control the output voltage of the transmitting-side AC / DC converter 1100 in consideration of the power demand of the wireless power receiving apparatus 2000, the current charging amount, and the wireless power scheme . The frequency and switching waveforms for driving the transmission side DC / AC conversion unit 1200 may be generated in consideration of the maximum power transmission efficiency to control power to be transmitted. In addition, the transmitting-side control unit 1510 can determine the size of the wireless power receiving apparatus based on the unique information (RXID) received from the wireless power receiving apparatus. That is, one of the plurality of transmission coils can be selected according to the size of the wireless power receiving apparatus. The unique information RXID may include an RXID message, a certification version, identification information, and an error detection code (CRC), but is not limited thereto. The RXID message may include information on the amount of power of the wireless power receiving apparatus.

Also, the overall operation of the wireless power receiving apparatus 2000 can be controlled using an algorithm, a program, or an application required for the control read from the storage unit (not shown) of the wireless power receiving apparatus 2000. Meanwhile, the transmission-side controller 1510 may be referred to as a microprocessor, a microcontroller unit, or a microcomputer. The transmission-side communication unit 1520 can perform communication with the reception-side communication unit 2620, and can use a short-distance communication scheme such as Bluetooth, NFC, Zigbee, etc. as a communication scheme. The transmission side communication unit 1520 and the reception side communication unit 2620 can transmit and receive the charging status information and the charging control command to each other. The charging status information may include the number of the wireless power receiving apparatuses 2000, the battery remaining amount, the number of charging times, the usage amount, the battery capacity, the battery ratio, and the transmission power amount of the wireless power transmission apparatus 1000. Further, the transmission side communication unit 1520 can transmit a charging function control signal for controlling the charging function of the wireless power receiving apparatus 2000, and the charging function control signal controls the wireless power receiving apparatus 2000 to perform the charging function And may be a control signal that enables or disables the device.

As described above, the transmitting-side communication unit 1520 may be communicated in an out-of-band format, which is a separate module, but the present invention is not limited thereto. And may perform communication in an in-band format using a feedback signal transmitted from the wireless power receiving apparatus to the wireless power transmitting apparatus. For example, the wireless power receiving apparatus may modulate the feedback signal to transmit information such as start of charge, end of charge, battery state, etc. to the transmitter through a feedback signal. The transmitting side communication unit 1520 may be configured separately from the transmitting side control unit 1510 and the receiving side communication unit 2620 may be included in the control unit 2610 of the receiving apparatus, Lt; / RTI &gt;

<Wireless Power Receiving Device>

4 is a block diagram illustrating a wireless power receiving apparatus as one of the subsystems constituting the wireless power transmission system.

4, a wireless power transmission system may include a wireless power transmission device 1000 and a wireless power reception device 2000 receiving wireless power from the wireless power transmission device 1000, The receiving apparatus 2000 includes a receiving side coil part 2100, a receiving side impedance matching part 2200, a receiving side AC / DC converting part 2300, a receiving side DC / DC converting part 2400, a load 2500, And a receiving-side communication and control unit 2600.

The receiving side coil part 2100 can receive power through a magnetic induction method or a self resonance method. As described above, at least one of the induction coil and the resonance coil may be included according to the power reception scheme. The receiving side coil part 2100 may be equipped with a near field communication (NFC) antenna. The receiving side coil part 2100 may be the same as the transmitting side coil part 1400 and the dimensions of the receiving antenna may be changed according to the electrical characteristics of the wireless power receiving device 2000.

The reception side impedance matching unit 2200 performs impedance matching between the wireless power transmission apparatus 1000 and the wireless power reception apparatus 2000.

The receiving-side AC / DC converter 2300 rectifies the AC signal output from the receiving-side coil part 2100 to generate a DC signal.

The receiving-side DC / DC converting section 2400 can adjust the level of the DC signal output from the receiving-side AC / DC converting section 2300 to the capacity of the load 2500.

The load 2500 may include a battery, a display, a voice output circuit, a main processor, and various sensors.

The receiving side communication and control unit 2600 can be activated by the wake-up power from the transmitting side communication and control unit 1500 and perform communication with the transmitting side communication and control unit 1500, Can control the operation of the subsystem of the &lt; / RTI &gt;

The wireless power receiving apparatus 2000 may include a single or a plurality of wireless power receiving apparatuses 2000 and may simultaneously receive energy from the wireless power transmitting apparatus 1000. That is, in the wireless power transmission system of the self resonance type, a plurality of target wireless power receiving apparatuses 2000 can receive power from one wireless power transmission apparatus 1000. At this time, the transmitting-side matching unit 1300 of the wireless power transmission apparatus 1000 may adaptively perform impedance matching between the plurality of wireless power receiving apparatuses 2000. This can be equally applied to a case where a plurality of reception side coil portions independent from each other in the magnetic induction system are provided.

When the plurality of wireless power receiving apparatuses 2000 are provided, the power receiving systems may be the same system or different systems. In this case, the wireless power transmission apparatus 1000 may be a system that transmits power by a magnetic induction method or a self-resonant method, or a system that mixes both methods.

Meanwhile, in the case of the wireless power transmission of the magnetic induction type, the transmission side AC / DC conversion unit 1100 in the wireless power transmission apparatus 1000 may transmit data of several tens or several hundreds V ( (For example, 10V to 20V), by receiving AC signals of several tens or hundreds of Hz (for example, 60Hz) of a predetermined voltage (for example, 110V to 220V) And the transmitting side DC / AC converting unit 1200 can receive an AC signal and output an AC signal of KHz band (for example, 125 KHz). The receiving AC / DC converting unit 2300 of the wireless power receiving apparatus 2000 receives AC signals of KHz band (for example, 125KHz) and receives AC signals of several V to several tens V, several hundred V (for example, 10V to 20V And the receiving side DC / DC converting section 2400 can output a DC signal of, for example, 5V suitable for the load 2500 and transmit the DC signal to the load 2500. In the case of the wireless power transmission of the self-resonance type, the transmitting side AC / DC converting unit 1100 in the wireless power transmitting apparatus 1000 may transmit power of several tens or hundreds of Hz (for example, 110V to 220V) (For example, 60 Hz), and can convert and output a DC signal of several V to several tens V and several hundred V (for example, 10 V to 20 V), and the transmission side DC / AC conversion unit 1200 can output DC It is possible to output an AC signal of MHz band (for example, 6.78 MHz). The receiving AC / DC converting unit 2300 of the wireless power receiving apparatus 2000 receives the AC signal of MHz (for example, 6.78 MHz) and receives the AC signal of several V to several tens V, several hundred V (for example, 10V to 20V) And the DC / DC conversion unit 2400 can output a DC signal of, for example, 5V suitable for the load 2500 and transmit it to the load 2500. The DC /

5 is a plan view showing a transmission coil part according to an embodiment of the present invention.

Referring to FIG. 5, the transmitting coil part 1400 of FIG. 4 may be implemented as a transmitting coil part 100a including a plurality of transmitting coils, and the transmitting coil part 100a may include a first transmitting coil 110a, And a second transmission coil 120a disposed inside the first transmission coil 110a.

The first transmission coil 110a and the second transmission coil 120a substantially transmit power in the wireless power transmission apparatus 1000. [ In this case, the first transmission coil 110a and the second transmission coil 120a may include at least one of a transmission induction coil and a transmission resonance coil according to a charging scheme. The first transmission coil 110a and the second transmission coil 120a are formed to have a space in the central region. Here, the first transmission coil 110a and the second transmission coil 120a may be wires wound several times. For example, the first transmission coil 110a and the second transmission coil 120a may be formed of a helical type or a spiral type. The first transmission coil 110a and the second transmission coil 120a may be formed in a circular or rectangular shape. Further, the lead wire is made of a conductive material and can be coated with an insulating material.

Side controller 1510 can determine the size of the wireless power receiving apparatus 2000 based on the unique information (RXID) received from the wireless power receiving apparatus. That is, one of the plurality of transmission coils can be selected according to the size of the wireless power receiving apparatus 2000. For example, when the size of the wireless power receiving apparatus 2000 is larger than the reference value, the first transmission coil may operate, and when the size of the wireless power receiving apparatus 2000 is smaller than the reference value, can do. The reference value may be an average value of the diameters of the plurality of transmission coils, but is not limited thereto.

The first transmission coil 110a and the second transmission coil 120a may have a circular shape and the diameter d1 of the first transmission coil 110a is 54 mm or more and 56 mm or less, The diameter d2 of the protrusion 120a may be 29 mm or more and 31 mm or less, but is not limited thereto.

The center of the first transmission coil 110a and the center of the second transmission coil 120a may coincide with each other, but the present invention is not limited thereto.

The first transmission coil 110a and the second transmission coil 120a may have the same charging scheme. According to an embodiment, the first transmission coil 110a and the second transmission coil 120a may have different charging schemes.

That is, when the wireless power receiving apparatus 2000 is identified, the wireless power transmitting apparatus 1000 according to an embodiment of the present invention may include a first transmitting coil 110a and a second transmitting coil 110b depending on the size of the coil of the wireless power receiving apparatus 2000 The second transmission coil 120a is selectively driven to improve the transmission efficiency of the wireless power transmission apparatus. At this time, the size of the coil of the wireless power receiving apparatus 2000 can be calculated by interpreting the unique information received from the wireless power receiving apparatus 2000.

6 is a plan view showing a transmission coil according to another embodiment of the present invention.

Referring to FIG. 6, the transmitting coil part 1400 of FIG. 4 may be implemented as a transmitting coil part 100b including a plurality of transmitting coils, the transmitting coil part 100b may include a first transmitting coil 110b, And a second transmission coil 120b disposed inside the first transmission coil 110b.

The first transmission coil 110b and the second transmission coil 120b may have an elliptical shape and the transverse width d3 of the first transmission coil 110b is 54 mm or more and 56 mm or less and the longitudinal width d6 is 47 mm And the width d4 of the second transmission coil 120b may be 29 mm or more and 31 mm or less and the longitudinal width d5 may be 19 mm or more and 21 mm or less.

The center of the first transmission coil 110b and the center of the second transmission coil 120b may coincide with each other, but the present invention is not limited thereto.

The first transmission coil 110b and the second transmission coil 120b may have the same charging scheme. According to the embodiment, the first transmission coil 110b and the second transmission coil 120b may have different charging schemes.

That is, in the wireless power transmission apparatus 1000 according to the embodiment of the present invention, when the wireless power receiving apparatus 2000 is detected, according to the size of the coil of the wireless power receiving apparatus 2000, The second transmission coil 120b is selectively driven to improve the transmission efficiency of the wireless power transmission apparatus. At this time, the size of the coil of the wireless power receiving apparatus 2000 can be calculated by interpreting the unique information received from the wireless power receiving apparatus 2000.

7 is a plan view showing a transmitting coil part according to another embodiment of the present invention.

Referring to FIG. 7, the transmission coil section 1400 of FIG. 4 may be implemented as a transmission coil section 100c including a plurality of transmission coils, and the transmission coil section 100c may include a first transmission coil 110b, A second transmission coil 120b disposed inside the first transmission coil 110b and a shielding portion 130a between the first transmission coil 110b and the second transmission coil 120c.

The first transmission coil 110c and the second transmission coil 120c may be in the form of a circle and the diameter of the first transmission coil 110c is 54 mm or more and 56 mm or less and the diameter of the second transmission coil 120c is 29 mm Or more and 31 mm or less, and the diameter of the shielding portion 130a may be 41 mm or more and 43 mm or less, but the present invention is not limited thereto.

The center of the first transmission coil 110c and the center of the second transmission coil 120c may coincide with each other, but the present invention is not limited thereto.

The first transmission coil 110c and the second transmission coil 120c may have the same charging scheme. According to the embodiment, the first transmission coil 110c and the second transmission coil 120c may have different charging schemes.

That is, in the wireless power transmission apparatus 1000 according to the embodiment of the present invention, when the wireless power receiving apparatus 2000 is detected, according to the size of the coil of the wireless power receiving apparatus 2000, The second transmission coil 120c is selectively driven to improve the transmission efficiency of the wireless power transmission apparatus. At this time, the size of the coil of the wireless power receiving apparatus 2000 can be calculated by interpreting the unique information received from the wireless power receiving apparatus 2000.

Also, in the embodiment, the shielding portion 130a can change the transmission path of some of the magnetic fields generated in the first transmission coil 110c and the second transmission coil 120c. The shielding portion 130a may include a magnetic material of a different type and may include, for example, a spinel type, a hexa type, a sandust type, a fermalloy type magnetic material, It does not. That is, the transmitting coil part 100c can improve the transmission efficiency by preventing the interference between the transmitting coils by arranging the shielding part 130a between the first transmitting coil 110c and the second transmitting coil 120c.

8 is a plan view showing a transmission coil according to another embodiment of the present invention.

Referring to FIG. 8, the transmitting coil part 1400 of FIG. 4 may be implemented as a transmitting coil part 100d including a plurality of transmitting coils, and the transmitting coil part 100d may include a first transmitting coil 110d, A second transmission coil 120d disposed inside the first transmission coil 110d and a shielding device 130b between the first transmission coil 110d and the second transmission coil 120d.

The first transmission coil 110d and the second transmission coil 120d may have an elliptic shape. The width of the first transmission coil 110d may be 54 mm or more and 56 mm or less, the vertical width may be 47 mm or more and 49 mm or less, 2 Transmission coil 120d may have a transverse width of 29 mm or more and 31 mm or less and a transverse width of 19 mm or more and 21 mm or less, but the invention is not limited thereto.

The center of the first transmission coil 110d and the center of the second transmission coil 120d may coincide with each other, but the present invention is not limited thereto.

The first transmission coil 110d and the second transmission coil 120d may have the same charging scheme. According to an embodiment, the first transmission coil 110d and the second transmission coil 120d may have different charging schemes.

That is, when the wireless power receiving apparatus 2000 is detected, the wireless power transmitting apparatus 1000 according to an exemplary embodiment of the present invention may include a first transmitting coil 110d and a second transmitting coil 110d according to the size of the coil of the wireless power receiving apparatus 2000 The second transmission coil 120d is selectively driven to improve the transmission efficiency of the wireless power transmission apparatus. At this time, the size of the coil of the wireless power receiving apparatus 2000 can be calculated by interpreting the unique information received from the wireless power receiving apparatus 2000.

In addition, in the embodiment, the shielding portion 130b can change the transmission path of some of the magnetic fields generated in the first transmission coil 110d and the second transmission coil 120d. The shielding portion 130b may include a magnetic material of a different type and may include, for example, a spinel type, a hexa type, a sandust type, a fermalloy type, It does not. That is, the transmitting coil part 100d can improve the transmission efficiency by preventing the interference between the transmitting coils by disposing the shielding part 130b between the first transmitting coil 110d and the second transmitting coil 120d.

9 and 10 are circuit diagrams illustrating a driving unit according to an embodiment of the present invention.

9, the transmitting side DC / AC converting unit 1200 of FIG. 4 is implemented as a half bridge inverter, and the power (power) The switch SW0 is turned on so that the inductor L1 operates so that the power of the wireless power receiving apparatus 2000 is the same as the power received from the wireless power receiving apparatus 2000. [ When the power is less than the reference power or the size of the wireless power receiving apparatus 2000 is smaller than the reference value according to the information RXID, the switch SW1 may be turned on so that the inductor L2 is operated. The capacitors C1 and C2 may be operated to perform impedance matching. For example, in an embodiment, the reference power may be 5 W, but is not limited thereto.

The reference value may be an average value of the diameters of the plurality of transmission coils, and the reference power may be 5 W, but is not limited thereto.

That is, the inductor L1 may be the first transmission coil 110a, 110b, 110c, or 110d of FIGS. 5 to 8 and the inductor L2 may be the second transmission coil 120a, 120b, 120c, and 120d.

10, the transmitter-side DC / AC converting unit 1200 of FIG. 4 is implemented as a full bridge inverter, and power (power) The switch SW0 is turned on so that the inductor L1 is operated and the specific information received from the wireless power receiving apparatus 2000 is transmitted to the wireless power receiving apparatus 2000. [ The switch SW1 may be turned on so that the inductor L2 is operated when the power is less than the reference power or the size of the wireless power receiving apparatus 2000 is smaller than the reference value according to the RXID. The capacitors C1 and C2 may be operated to perform impedance matching. For example, in an embodiment, the reference power may be 5 W, but is not limited thereto.

That is, the inductor L1 may be the first transmission coil 110a, 110b, 110c, or 110d of FIGS. 5 to 8 and the inductor L2 may be the second transmission coil 120a, 120b, 120c, and 120d.

According to the embodiment, when the power is higher than the reference power or the size of the wireless power receiving apparatus 2000 is larger than the reference value, according to the unique information (RXID) received from the wireless power receiving apparatus 2000, If the power is less than the reference power or the size of the wireless power receiving apparatus 2000 is smaller than the reference value according to the unique information (RXID) received from the wireless power receiving apparatus 2000, The bridge inverter may be driven, but is not limited thereto. The reference value may be an average value of the diameters of the plurality of transmission coils, and the reference power may be 5 W, but is not limited thereto.

11 is a flowchart illustrating a charging method of a wireless power transmission apparatus according to an embodiment of the present invention.

Referring to FIG. 11, the wireless power transmission apparatus 1000 transmits an analog signal in a standby state (S1210).

When the wireless power receiving apparatus 2000 is searched, the wireless power transmitting apparatus 1000 transmits a digital signal to the wireless power receiving apparatus 2000 (S1220). The frequency of the digital signal may be 285 kHz or higher and 315 kHz or lower, for example, five or less digital signals may be transmitted for a time period of 28 ms or less, and the wireless power receiving apparatus 2000 may return to a standby state have.

The wireless power receiving apparatus 2000 can transmit the power signal to the wireless power transmitting apparatus 1000 (S1230). The frequency of the power signal may be 215 kHz or more and 220 kHz or less, but is not limited thereto.

The wireless power transmission apparatus 1000 can receive the unique information RXID of the wireless power receiving apparatus 2000 when the power signal received from the wireless power receiving apparatus 2000 is valid (S1130) (S1140).

The wireless power transmission apparatus 1000 determines whether the unique information RXID is valid in step S1150 and may compare the power of the wireless power receiving apparatus 2000 with the reference power according to the unique information RXID (S1160).

When the power of the wireless power receiving apparatus 2000 is larger than the reference power, the wireless power transmitting apparatus 1000 can select the first transmitting coil to transmit the power (S1170), and the power of the wireless power receiving apparatus 2000 If it is smaller than the reference power, the wireless power transmission apparatus 1000 may select the second transmission coil and transmit the power (S1180).

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

100a, 100b, 100c; Transmitting coil part
110a, 110b, 110c, 110d; The first transmission coil
120a, 120b, 120c, 120d; The second transmission coil
130a, 130b; Shielding portion

Claims (12)

A transmitting coil part including a plurality of transmitting coils for transmitting AC power to a wireless power receiving device; And
And a transmitting side control unit for determining the size of the wireless power receiving apparatus based on the unique information (RXID) received from the wireless power receiving apparatus and selecting one of the plurality of transmitting coils according to the size of the wireless power receiving apparatus Gt; The method according to claim 1,
Wherein the transmit coils comprise a first transmit coil,
And a second transmission coil disposed inside the first transmission coil,
Wherein when the size of the wireless power receiving apparatus is larger than a reference value, the first transmission coil operates. 3. The method of claim 2,
Wherein when the size of the wireless power receiving apparatus is smaller than a reference value, the second transmission coil operates. The method according to claim 1,
Further comprising a driver for selectively driving one of a half bridge or a full bridge depending on a size of the wireless power receiving apparatus. The method according to claim 1,
Wherein the transmitting coils have the same charging scheme. The method according to claim 1,
Wherein the transmit coils have a different charging scheme. 3. The method of claim 2,
The transmitting coils are circular,
The diameter of the first transmission coil is 54 mm or more and 56 mm or less, and the diameter of the second transmission coil is 29 mm or more and 31 mm or less. 3. The method of claim 2,
The transmitting coils are elliptical,
The first transmission coil has a transverse width of 54 mm or more and 56 mm or less, a longitudinal width of 47 mm or more and 49 mm or less,
Wherein the width of the second transmission coil is 29 mm or more and 31 mm or less and the vertical width is 19 mm or more and 21 mm or less. 5. The method of claim 4,
Wherein the driving unit drives the half bridge when the size of the wireless power receiving apparatus is smaller than a reference value. 5. The method of claim 4,
Wherein the driving unit drives the full bridge when the size of the wireless power receiving apparatus is larger than a reference value. 3. The method of claim 2,
The center of the first transmission coil coincides with the center of the second transmission coil. 11. A wireless power transmission apparatus according to any one of claims 1 to 11; And
And a wireless power receiving device for receiving power from the wireless power transmitting device.

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