KR20170137494A - A wireless power transmitter - Google Patents

Abstract

A wireless power transmitter according to an embodiment of the present invention transmits wireless power to a wireless power receiver. The wireless power transmitter includes: a control circuit for controlling the wireless power transmitter; at least one transmission coil for transmitting the wireless power to the wireless power receiver; an internal shielding material arranged between the control circuit and the transmission coil; a housing having the control circuit, the internal shielding material, and the transmission coil arranged therein and including a plurality of surfaces; and an external shielding material surrounding other surfaces except for a surface in contact with the wireless power receiver among the plurality of surfaces of the housing. Accordingly, the present invention can prevent electromagnetic interference by shielding electromagnetic waves.

Description

[0001] A WIRELESS POWER TRANSMITTER [0002]

The present invention relates to a wireless power transmitter.

2. Description of the Related Art Generally, various electronic apparatuses are equipped with a battery and are driven by using electric power charged in the battery. At this time, in the electronic device, the battery can be replaced and recharged again. To this end, the electronic device has a contact terminal for contact with an external charging device. That is, the electronic device is electrically connected to the charging device through the contact terminal. However, as the contact terminal is exposed to the outside in the electronic device, it may be contaminated by foreign substances or short-circuited by moisture. In this case, there is a problem that a contact failure occurs between the contact terminal and the charging device, and the battery is not charged by the electronic device.

In order to solve the above problems, a wireless power transfer (WPT) for charging an electronic device wirelessly has been proposed. The wireless power transmission system is a technology that transfers power without a line through space and maximizes the convenience of power supply to mobile devices and digital home appliances. The wireless power transmission system has advantages such as saving energy through real-time power usage control, overcoming space limit of power supply, and reducing waste battery discharge by battery recharging.

As a method of implementing a wireless power transmission system, there are typically a magnetic induction type and a self resonance type. The magnetic induction method is a noncontact energy transmission technique in which two coils are brought close to each other, a current is supplied to one coil, and an electromotive force is generated in the other coil via the magnetic flux generated thereby. The self-resonance method is a magnetic resonance technique that uses only electric fields or magnetic fields without using electromagnetic waves or currents, and the distance capable of power transmission is several meters or more, and a band of several MHz can be used.

The wireless power transmission system includes a transmitting device that transmits power wirelessly and a receiving device that receives power to charge a load such as a battery. At this time, a charging method of a receiving apparatus, that is, a charging method of either a magnetic induction method or a self-resonance method can be adopted, and a transmitting apparatus capable of transmitting power wirelessly corresponding to a charging method of a receiving apparatus has been developed.

A wireless power transmitter according to an embodiment of the present invention blocks electromagnetic waves emitted to the outside of the wireless power transmitter.

The wireless power transmitter according to an embodiment of the present invention includes an external shielding member for shielding electromagnetic waves emitted to the outside of the wireless power transmitter, in addition to an inner shielding member for protecting electronic circuits inside the wireless power transmitter.

A wireless power transmitter disposed within an electric vehicle according to an embodiment of the present invention includes an internal shielding member for protecting electronic circuits inside the wireless power transmitter and a shielding member for shielding electromagnetic waves emitted to the outside of the wireless power transmitter And includes an external shielding material.

A wireless power transmitter for transmitting wireless power to a wireless power receiver according to an embodiment of the present invention comprises: a control circuit for controlling the wireless power transmitter; At least one transmit coil for transmitting the wireless power to the wireless power receiver; An inner shielding material disposed between the transmission coil and the control circuit; A housing including the control circuit, the inner shield, the transmitting coil, and a plurality of surfaces; And an outer shield surrounding the other of the plurality of surfaces of the housing, except for a surface contacting the wireless power receiver.

A wireless power transmitter according to an embodiment of the present invention can block electromagnetic interference to other electronic devices located outside the wireless power transmitter by blocking electromagnetic waves emitted to the outside of the wireless power transmitter.

The wireless power transmitter according to an embodiment of the present invention includes an external shielding material for shielding electromagnetic waves emitted to the outside of the wireless power transmitter in addition to an inner shielding material for protecting the electronic circuit inside the wireless power transmitter, It is possible to block electromagnetic interference to other electronic devices located outside the wireless power transmitter.

A wireless power transmitter disposed within an electric vehicle according to an embodiment of the present invention includes an internal shielding member for protecting electronic circuits inside the wireless power transmitter and a shielding member for shielding electromagnetic waves emitted to the outside of the wireless power transmitter By including the external shielding material, electromagnetic interference to the electronic devices inside the electric vehicle located outside the wireless power transmitter can be blocked.

1 is a magnetic induction equivalent circuit.
2 is a self-resonant-type equivalent circuit.
3A and 3B are block diagrams showing a transmitting apparatus as one of the subsystems constituting a wireless power transmission system.
4A and 4B are block diagrams showing a receiver as one of the subsystems constituting the wireless power transmission system.
5 is a flowchart illustrating an operation of the wireless power transmission system, and is a flowchart illustrating the operation of the wireless power transmission apparatus.
6 shows a wireless power transmission / reception environment according to the prior art.
FIG. 7 illustrates a wireless power transmitter and wireless power transmission and reception environment in accordance with an embodiment of the present invention.
8 is an exploded view of a wireless power transmitter in accordance with an embodiment of the present invention.
9 is a cross-sectional view of a wireless power transmitter in accordance with an embodiment of the present invention.
10 shows a vehicle equipped with a wireless power transmitter according to an embodiment of the present invention.
11 shows a wireless power transmitter according to an embodiment of the present invention.
12 shows a vehicle equipped with a wireless power transmitter according to another embodiment of the present invention.
13 illustrates a wireless power transmitter in accordance with another embodiment of the present invention.
14 illustrates a wireless power transmitter in accordance with another embodiment of the present invention.

Hereinafter, a wireless power transmission system including a transmitter having a function of transmitting power wirelessly and a receiver receiving power wirelessly 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.

S parameter (Scattering parameter): S parameter is the ratio of input voltage to output voltage input port-output port, the ratio of the frequency distribution; in its reflectance value, i.e. their type of (Transmission S ₂₁₎ or each I / O port (Reflection (S ₁₁ , S ₂₂ )).

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 that the electromotive force to generate a source inductor (L _s) and a load inductor (L _ℓ) to the close proximity to each other the magnetic flux to the load inductor as a medium (L _ℓ) generated spill the current source inductor (L _s) of the one side Contact energy transfer technology. 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.

1, in a magnetic induction equivalent circuit, a transmitter includes a source voltage V _s , a source resistance R _s , a source capacitor C _s for impedance matching, It may be implemented as a coupling source coil (L _s) for, receiving a load for the magnetic coupling of the load capacitors (C _ℓ) and the transmission unit for the load resistance (R _ℓ) equivalent resistance of the receiver, impedance matching magnetic coupling of the coils may be implemented in (L _ℓ), the source coil (L _s) and a load coil (L _ℓ) degree may be represented by a mutual inductance (M _sℓ).

In FIG. 1, the ratio (S ₂₁ ) of the input voltage to the output voltage is obtained from a magnetic induction equivalent circuit consisting solely of a coil without a source capacitor C _s and a load capacitor C _l for impedance matching, The maximum power transmission condition satisfies Equation (1) below.

Equation 1

L _s / R _s = L _ℓ / R _ℓ

Maximum power transmission is possible when the ratio of the inductance of the transmission coil L _s to the source resistance R _s and the ratio of the inductance of the load coil L _L to the load resistance R _L are equal to each other. Since there is no capacitor capable of compensating reactance in a system having only inductance, the value of the self reflection value (S ₁₁ ) of the input / output port can not be zero at the point where the maximum power transfer occurs, The power transmission efficiency may vary greatly depending on the value (M _s ). Thus, the source capacitor C _s can be added to the transmitter as a compensation capacitor for impedance matching, and the load capacitor C _l can be added to the receiver. The compensation capacitors C _s , C _l may be connected in series or in parallel to the receiving coil L _s and the load coil L _l , respectively, for example. For impedance matching, a passive element such as an additional capacitor and an inductor may be added to each of the transmitter and the receiver as well as the compensation capacitor.

2 is a self-resonant-type equivalent circuit.

2, in a self-resonant-type equivalent circuit, a transmitter includes a source coil constituting a closed circuit by a series connection of a source voltage V _s , a source resistance R _s and a source inductor L _s , side of the resonance inductor (L1) and is implemented in the transmission side resonance coil (resonant coil) constituting a closed circuit in series connection of the transmission side resonance capacitor (C1), receiving a load resistance (R _ℓ) and a load inductor (L _ℓ) Side resonant coil constituting a closed circuit by a series connection of a load coil constituting a closed circuit in series connection, a resonant inductor L2 on the reception side and a resonant capacitor C2 on the reception side, and the source inductor L _s And the transmission side resonance inductor L1 are magnetically coupled with the coupling coefficient of K01 and the load inductor L _? And the load side resonance inductor L2 are magnetically coupled with the coupling coefficient of K23, (L1) and the reception-side resonance inductor (L2) Channels are magnetically coupled. 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 two resonators have the same resonance frequency, most of the energy of the resonator of the transmitter is transmitted to the resonator of the receiver so that the power transfer efficiency can be improved, and the efficiency in the self resonance method satisfies Equation When it gets better.

Equation 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.

<Transmitter>

FIGS. 3A and 3B are block diagrams showing a transmitter as one of subsystems configuring a wireless power transmission system.

Referring to FIG. 3A, a wireless power transmission system according to an embodiment of the present invention may include a transmitter 1000 and a receiver 2000 that receives power wirelessly from the transmitter 1000. FIG. The transmission unit 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, a transmission unit 101 for generating a magnetic field based on the AC signal output from the power conversion unit 101, The power conversion unit 101 and the power conversion unit 101. The resonance circuit unit 102 and the power conversion unit 101 are connected to the power conversion unit 101 and the power conversion unit 101, And a control unit 103 for sensing impedance, voltage and current information from the power conversion unit 101 and the resonant circuit unit 102 and wirelessly communicating with the receiving unit 2000 can do. 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 transmitting unit 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 transmitting coil unit 1400 And a transmission side communication and control unit 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 transmitting unit 1000 and the receiving unit 2000 are spatially separated and the leakage of the magnetic field is large, the impedance difference between the two connecting ends of the transmitting unit 1000 and the receiving unit 2000 is corrected, . 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 have an inductive coupling between the transmission unit 1000 and the reception unit 2000 The energy loss can be minimized by increasing the coefficient. When the wireless power transmission system transmits power in a self-resonant manner, the transmission-side impedance matching unit 1300 may change the separation distance between the transmission unit 1000 and the reception unit 2000, or may change a foreign object (FO) It is possible to perform real-time correction of the impedance matching according to the change of the matching impedance on the energy transmission line due to the change of the characteristics of the coil due to the mutual influence by the device of the capacitor, A matching method, 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 transmission-side controller 1510 may control the output voltage of the transmission-side AC / DC converter 1100 in consideration of the power demand of the receiver 2000, the current charge 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. Also, the overall operation of the receiver 2000 can be controlled by using an algorithm, a program, or an application required for the control read from the storage unit (not shown) of the receiver 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 receiving unit 2000, the remaining battery level, the number of times of charging, the amount of usage, the battery capacity, the battery ratio, and the transmission power amount of the transmission unit 1000. Side communication unit 1520 can transmit a charging function control signal for controlling the charging function of the receiving unit 2000 and the charging function control signal controls the receiving unit 2000 to enable or disable the charging function And may be a control signal for disabling the control signal.

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 to be transmitted to a transmitter. For example, the receiver may modulate the feedback signal to transmit information such as start of charge, end of charge, battery condition, etc. to the transmitter through a feedback signal. The transmission side communication unit 1520 may be configured separately from the transmission side control unit 1510 and the reception side communication unit 2620 may be included in the control unit 2610 of the reception device or separately have.

In addition, the transmission unit 1000 of the wireless power transmission system according to the embodiment may further include a detection unit 107.

The detection unit 107 detects an input signal of the transmitting side AC / DC converting unit 1100, an output signal of the transmitting side AC / DC converting unit 1100, an input signal of the transmitting side DC / AC converting unit 1200, The input signal of the transmission side impedance matching unit 1300, the output signal of the transmission side impedance matching unit 1300, the input signal of the transmission side coil 1400, or the transmission side coil 1400). &Lt; / RTI &gt; The detected signal is fed back to the communication and control unit 1500 and the communication and control unit 1500 controls the transmission side AC / DC conversion unit 1100, the transmission side DC / AC conversion unit 1200, the transmission side impedance matching The control unit 1300 can be controlled. Also, the communication and control unit 1500 can perform a foreign object detection (FOD) based on the detection result of the detection unit 1600. And the detected signal may be at least one of a voltage and a current. On the other hand, the detection unit 107 may be configured by hardware different from the communication and control unit 1500, or may be implemented by one hardware.

<Receiver>

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

4, the wireless power transmission system may include a transmitting unit 1000 and a receiving unit 2000 receiving radio power from the transmitting unit 1000. The receiving unit 2000 includes a receiving coil unit 2100 A receiving side AC / DC converting unit 2300, a DC / DC converting unit 2400, a load 2500, and a receiving side communication and controlling unit 2600. The receiving side AC / DC converting unit 2300 includes a receiving side impedance matching unit 2200,

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 receiving part 200. [

The receiving-side impedance matching unit 2200 performs impedance matching between the transmitter 1000 and the receiver 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 performs communication with the transmitting side communication and control unit 1500, The operation of the system can be controlled.

The receiving unit 2000 includes a single or a plurality of receiving units 2000, and can simultaneously receive energy from the transmitting unit 1000 wirelessly. That is, in the self-resonant wireless power transmission system, a plurality of target receivers 2000 can receive power from one transmitter 1000. At this time, the transmitter matching unit 1300 of the transmitter 1000 may adaptively perform impedance matching between the plurality of receivers 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 receiving unit 2000 includes a plurality of units, the power receiving systems may be the same system or different types of systems. In this case, the transmitting unit 1000 may be a system for transmitting power by a magnetic induction system or a self-resonance system, or a system for mixing both systems.

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

&Lt; Operation state of the transmitter &

5 is a flowchart illustrating an operation of the wireless power transmission system, and is a flowchart illustrating an operation of the wireless power transmission system.

5, a transmitter according to an embodiment may have at least 1) a standby state, 2) a digital ping state, 3) an authentication state, 4) a power transmission state, and 5) a charge end state.

[Standby]

(1) When the transmitter 1000 is powered from the outside and the transmitter 1000 is started, the transmitter 1000 may be in a standby state. The transmitting unit 1000 in the standby state can detect the presence of an object (for example, the receiving unit 2000 or metallic foreign matter FO) disposed in the charging area. Also, the transmitter 1000 can detect whether or not the object is removed from the charging area.

(2) As a method of detecting the presence of an object in the charging area, the transmitter 1000 may monitor the object by monitoring the change of the magnetic flux, the change in capacitance or inductance between the object and the transmitter 1000, But is not limited thereto.

(3) If the transmitter 1000 detects an object that is the receiver 2000 in the charging area, the digital ping state can be shifted to the next step.

(4) The transmitter 1000 can detect the FO such as metallic foreign matter in the charged area.

(5) On the other hand, if the transmitter 1000 does not acquire enough information to distinguish between the receiver 2000 and the FO in the waiting state, the receiver goes to the digital ping state or goes to the authentication state, .

[Digital ping]

(1) In the digital ping state, the transmission unit 1000 is connected to the chargeable reception unit 2000, and confirms that it is an effective reception unit 2000 that can be charged with radio power provided from the transmission unit 1000. [ The transmission unit 1000 may generate and output a digital ping having a predetermined frequency and timing to be connected to the chargeable reception unit 2000.

(2) If a sufficient power signal for digital ping is transmitted to the receiving unit 2000, the receiving unit 2000 can respond to the digital ping by modulating the power signal according to a communication protocol. If the transmitting unit 1000 receives a valid signal from the receiving unit 2000, the receiving unit 2000 can proceed to the authentication state without removing the power signal. If the EOC request is received from the receiving unit 2000, the transmitting unit 1000 may proceed to the charging end state.

(3) When the effective receiving unit 2000 is not detected or the response time of the object for the digital ping exceeds a preset time, the transmitting unit 1000 can return to the standby state by removing the power signal. Therefore, if the FO is placed in the charging area, the transmitter 1000 can return to the standby state because the FO can not make any response.

[Identification]

(1) When the response of the receiving unit 2000 according to the digital ping of the transmitting unit 1000 is completed, the transmitting unit 1000 transmits the transmitting unit authentication information to the receiving unit 2000 to check compatibility between the transmitting and receiving units 1000 and 2000 . When the compatibility is confirmed, the receiving unit 2000 can transmit the authentication information to the transmitting unit 1000. [ The transmitting unit 1000 can confirm the receiving unit authentication information of the receiving unit 2000.

(2) When the mutual authentication is completed, the transmitter 1000 proceeds to the power transmission state. If the authentication fails, or the authentication time exceeds the predetermined authentication time, the transmitter 1000 can return to the standby state.

[Power Transfer State]

(1) The communication and control unit 1500 of the transmission unit 1000 can provide charging power to the reception unit 2000 by controlling the transmission unit 1000 based on the control data provided from the reception unit 2000.

(2) Further, the transmitter 1000 can verify that the proper operation range is not exceeded or that the stability according to the FOD is not problematic.

(3) If the transmitter 1000 receives a charge completion signal from the receiver 2000 or if it exceeds the preset limit temperature, the transmitter 1000 can stop the power transmission and proceed to the charging completion state .

(4) In the case of a situation where the power is not suitable for transmission, the power signal can be removed and returned to the standby state. If the receiving unit 2000 enters the charging area again after the receiving unit 2000 is removed, the above-described cycle can be performed again.

(5) It is also possible to return to the authenticated state in accordance with the charged state of the load 2500 of the receiving unit 2000, and to provide the adjusted charging power to the receiving unit 2000 based on the state information of the load 2500.

[End of Charge (EOC))

(1) The transmitter 1000 can receive the information that the charging is completed from the receiver 2000 or can go to the charging completion state when receiving information that the receiver 2000 has risen above a predetermined temperature.

(2) When the transmitting unit 1000 receives the charging completion information from the receiving unit 2000, the transmitting unit can stop the power transmission and wait for a predetermined time. After a predetermined time has elapsed, the transmitter 1000 may enter the digital ping state to be connected to the receiver 2000 disposed in the charging area.

(3) When the transmitter 1000 receives information that the preset temperature has been exceeded from the receiver 2000, it can wait for a predetermined time. After a predetermined time elapses, the transmitter 1000 may enter the digital ping state to be connected to the receiver 2000 disposed in the charge area.

(4) The transmitter 1000 can monitor whether the receiver 2000 is removed from the charging area for a predetermined time, and can return to the standby state when the receiver 2000 is removed from the charging area.

6 shows a wireless power transmission / reception environment according to the prior art.

Referring to FIG. 6, the wireless power transmitter 601 and the wireless power receiver 603 may be located close to each other. In addition, external electronic devices 1 to 4 may be located in the vicinity of the wireless power transmitter 601 and the wireless power receiver 603. The number of external electronic devices may vary according to various embodiments of the present invention.

The wireless power transmitter 601 may transmit wireless power to the wireless power receiver 603. [ At this time, the wireless power transmitter 601 may emit harmful electromagnetic waves to the external electronic devices 1 to 4. That is, electromagnetic interference (EMI) may be generated by the wireless power transmitter 601 to the external electronic devices 1 to 4. Accordingly, the external electronic devices 1 to 4 may cause electrical damage due to the electromagnetic interference by the wireless power transmitter 601.

FIG. 7 illustrates a wireless power transmitter and wireless power transmission and reception environment in accordance with an embodiment of the present invention.

Referring to FIG. 7, the wireless power transmitter 701 and the wireless power receiver 705 may be located close to each other. In addition, external electronic devices 1 to 4 may be located near the wireless power transmitter 701 and the wireless power receiver 705. The number of external electronic devices may vary according to various embodiments of the present invention.

The wireless power transmitter 701 according to an embodiment of the present invention may include an external shield 703 capable of shielding electromagnetic interference. That is, outside of the wireless power transmitter 701, an external shield 703 for blocking electromagnetic interference that can electrically damage the external electronic devices 1 to 4 may be disposed.

The external shielding member 703 according to the embodiment of the present invention can block electromagnetic waves of 1 MHz or less. Specifically, the external shielding material 703 can block electromagnetic waves in and out of the 300 kHz band except the frequency of the 110 kHz band for wireless power transmission. For example, the external shielding material 703 may block electromagnetic waves having a frequency within a range of 120 kHz to 300 kHz.

According to an embodiment of the present invention, the outer shield 703 may be arranged to surround the surfaces of the plurality of sides of the wireless power transmitter 701 except the side in contact with the wireless power receiver 705. [ According to another embodiment of the present invention, the outer shield 703 may be coated on the surfaces of the plurality of sides of the wireless power transmitter 701 except the side in contact with the wireless power receiver 705. [ For example, the outer shield 703 may be coated on at least one of the outer and inner surfaces of the wireless power transmitter 701 without a separate adhesive.

In accordance with an embodiment of the present invention, the outer shield 703 may also be disposed on top of the surface where the wireless power receiver 705 is disposed. The wireless power receiver 705 can be disposed on the top of the wireless power receiver 705 except for a space where the wireless power receiver 705 can receive power from the wireless power transmitter 701 to prevent the electromagnetic wave from being leaked to the outside. For example, an external shielding agent 703 may be disposed in the form of a lid surrounding the wireless power receiver 705.

The wireless power transmitter 701 according to the embodiment of the present invention can block and minimize the electromagnetic waves generated between the wireless power transmission and prevent malfunction of the electronic devices such as the environmentally friendly electric vehicle which is recently being spotlighted.

8 is an exploded view of a wireless power transmitter in accordance with an embodiment of the present invention.

8, the wireless power transmitter 801 includes an upper cover 803, a coil frame 805, a plurality of coils 807, an inner shield 809, a metal sheet 811, a control circuit board 813, A lower cover 815, and an external shielding material 817. [

The coil mounted on the wireless power transmitter 801 may have various specifications, and the shape, size, temperature characteristics, power transmission efficiency, connection characteristics, etc. of the coils having various specifications may vary depending on the specifications. Thus, the wireless power transmitter 801 can be tailored to fit the coils that are targets of the various coils.

8 shows an embodiment in which the wireless power transmitter 801 is mounted with three coils 807 overlapping each other, but the scope of the present invention is not limited thereto and any number (e.g., one, four, etc.) May be disposed at arbitrary positions.

Each of the plurality of coils 807 may be formed in the form of a spiral wound wire, and the end face of the wire may include a conductive material (for example, copper (Cu)) and an insulating material surrounding the conductive material.

The coil frame 805 can provide a frame so that the plurality of coils 807 can be mounted. The coil frame 805 may be made of reinforced plastic, but the scope of the present invention is not limited thereto. When the coil frame 805 is made of reinforced plastic, the overall weight of the wireless power transmitter 801 can be reduced while protecting the plurality of coils 807 from external impact and breakage.

Each of the plurality of coils 807 may be overlapped with each other so that a wireless chargeable region is completely separated and a dead spot, which is a non-chargeable region, is not generated. .

The inner shield 809 shields the magnetic field generated by the plurality of coils 807 to prevent the magnetic field from being transmitted to the control circuit board 813. The inner shielding member 809 may be formed of a ferrite sheet, but the scope of the present invention is not limited thereto.

The metal sheet 809 may function as a heat sink to maintain the shape of the wireless power transmitter 801 and to allow heat generated from the plurality of coils 807 to be emitted to the outside. The metal sheet 809 may be implemented to include aluminum (Al), but the scope of the present invention is not limited thereto.

The inner shielding material 809 and the metal sheet 813 may be disposed inside the coil frame 805. The metal sheet 809 may include a connector. The connector allows a plurality of coils 807 to be connected to the control circuit board 813 via the coil frame 805. [

The upper cover 803 and the lower cover 815 may be referred to as housings. A wireless power receiver 801 may be placed on the top surface of the top cover 803. [ The upper cover 803 and the lower cover 803 are used to prevent the coil frame 805, the plurality of coils 807, the inner shielding material 809, the metal sheet 811, .

According to an embodiment of the present invention, the outer shielding material 817 may be disposed to surround at least one of the inner and outer surfaces of the lower cover 815. [ That is, the external shielding material 817 may be disposed to surround other surfaces of the plurality of sides of the wireless power transmitter 801 except the side in contact with the wireless power receiver. Accordingly, the external shielding material 817 can shield the electromagnetic interference by the wireless power transmitter 801. [

9 is a cross-sectional view of a wireless power transmitter in accordance with an embodiment of the present invention.

9, the wireless power transmitter 901 includes an upper cover 903, a coil frame 905, a plurality of coils 907, an inner shielding material 909, a metal sheet 911, a control circuit board 913 ), A lower cover 915, and an external shielding material 917.

The outer side surfaces of the upper cover 903 according to the embodiment of the present invention may be surrounded by the outer shielding material 917. [ For example, the external shielding material 917 may be disposed on outer sides or inner side surfaces of the plurality of sides of the upper cover 903 except for the upper surface that contacts the wireless power receiver.

9, the external shielding member 917 may be disposed on all of a plurality of surfaces of the lower cover 915. [ For example, the external shielding material 917 may be disposed on at least one of an inner surface and an outer surface of the lower cover 915. [

The external shielding member 917 according to the embodiment of the present invention may be disposed in a space between the control circuit board 913 and the lower cover 915 when disposed on the inner surface of the lower cover 915. [ For example, the external shielding material 917 is disposed in the space between the control circuit board 913 and the lower cover 915, and further disposed on the inner or outer surface of the lower cover 915, Thereby enhancing the shielding effect.

The external shielding member 917 may be a magnetic sheet including a magnetic body. For example, the magnetic material may include at least one of an amorphous ribbon, a nanocrystalline ribbon, and a silicon steel sheet.

According to another embodiment of the present invention, of the plurality of surfaces of the upper cover 903, the surface except for the upper surface contacting with the wireless power receiver may be integrated with the outer shielding member 917. For example, the upper cover 903 may be an injection molded article including a magnetic substance of a sendust series constituting the outer shielding member 917. [ Further, the lower cover 915 may be integrated with the external shielding member 917. [ Likewise, the lower cover 915 may be an injection molded product including a magnetic substance of a sensor type constituting the external shielding material 917. [

For example, the magnetic substance of the Sendut series is formed by melting a surface-insulated flake powder and insulating resin powder and forming a core layer composed of an insulating material for separating the flake powders from each other and an outer exposed portion And an insulating coating layer for preventing surface oxidation and antioxidation.

At this time, the core layer may have a high density of metal particles as well as a high planar magnetic performance by uniformly stacking the flake powders. In particular, the flake powder may be composed of a metal alloy soft magnetic powder and a chemical additive applied for surface insulation of the metal alloy soft magnetic powder. In another example, the flake powder may be composed of specific metal particles having conductivity and chemical additives applied for surface insulation of the metal particles.

10 shows a vehicle equipped with a wireless power transmitter according to the present invention.

10, the wireless power transmitter 1003 can be disposed inside the vehicle 1001. [ The wireless power transmitter 1003 may transmit wireless power to the wireless power receiver 1007. The wireless power receiver 1003 may be a smartphone, and the vehicle 1001 may be an electric vehicle. A plurality of electronic devices may be disposed inside the electric vehicle.

Other surfaces of the plurality of outer surfaces of the housing of the wireless power transmitter 1003 other than the upper surface contacting the wireless power receiver 1007 may be surrounded by the outer shield 1005 according to an embodiment of the present invention. The outer shield 1005 may be disposed on at least one of the inner and outer surfaces of the housing of the wireless power transmitter 1003. The external shielding member 1005 shields the electromagnetic field so as to prevent electromagnetic interference to a plurality of electronic devices disposed inside the electric vehicle.

The external shielding member 1005 may be a magnetic sheet including a magnetic body. The magnetic material may include at least one of an amorphous ribbon, a nano-stalin ribbon, and a silicon steel sheet. In accordance with various embodiments of the present invention, the housing of the wireless power transmitter 1003 may be integral with the outer shield 1005. For example, the housing of the wireless power transmitter 1003 may be an injection molded product including a magnetic substance of a sensor type constituting the external shielding material 1005.

11 shows a wireless power transmitter according to an embodiment of the present invention.

11, other surfaces of the plurality of surfaces of the housing of the wireless power transmitter 1101, except for the surface that contacts the wireless power receiver 1107, may be surrounded by the outer shield 1103. According to another embodiment of the present invention, the wireless power transmitter 1101 may include a shielding cover 1105. The shielding cover 1105 may be a magnetic sheet including a magnetic body. The magnetic material may include at least one of an amorphous ribbon, a nano-stalin ribbon, and a silicon steel sheet. One side of the shielding cover 1105 can be opened. A wireless power receiver 1107 may be disposed on the top surface of the wireless power transmitter 1101 via the open surface to receive wireless power from the wireless power transmitter 1101.

A portion of the shielding cover 1105 may be secured to a portion of the housing of the wireless power transmitter 1101. For example, the shielding cover 1105 may close or open the space in which the wireless power transmitter 1101 receives the wireless power receiver 1107.

12 shows a vehicle equipped with a wireless power transmitter according to another embodiment of the present invention.

12, the wireless power transmitter 1203 may be located inside the vehicle 1201. [ The wireless power transmitter 1203 may transmit wireless power to the wireless power receiver 1207. For example, the wireless power receiver 1207 may be a smartphone, and the vehicle 1201 may be an electric vehicle. A plurality of electronic devices may be disposed inside the electric vehicle.

The wireless power receiver 1207 may contact the top surface of the housing of the wireless power transmitter 1203 to receive wireless power from the wireless power transmitter 1203. The housing of the wireless power transmitter 1203 may include a receiving portion 1205 for receiving the wireless power receiver 1207. [ At least one of the inner and outer surfaces of the receiving portion may be surrounded by the shielding material. In addition, other surfaces of the wireless power transmitter 1203, other than the surface that contacts the wireless power receiver 1207, may be surrounded by a shielding material. Accordingly, the wireless power transmitter 1203 can block electromagnetic interference to other electronic devices in the vehicle through the shielding material.

The shielding material may be a magnetic sheet including a magnetic material. The magnetic material may include at least one of an amorphous ribbon, a nano-stalin ribbon, and a silicon steel sheet. The shielding member may be integrated with the receiving portion 1205. For example, the accommodating portion 1205 may be an injection molded product including a magnetic substance of a sensor type that constitutes the shielding material.

13 illustrates a wireless power transmitter in accordance with another embodiment of the present invention.

Referring to FIG. 13, the wireless power transmitter 1301 may be surrounded by an external shielding material 1303. For example, other surfaces of the plurality of sides of the wireless power transmitter 1301 other than the side contacting the wireless power receiver 1307 may be enclosed by the outer shield 1303. Wireless power transmitter 1301 may include receiver 1305. The outer surface of the receiving portion 1305 may be surrounded by a shielding material of the same material as the outer shielding material 1303. The receiving portion 1305 may include a cover 1309 for increasing the shielding effect on the electromagnetic field emitted by the wireless power transmitter 13010. A portion of the cover 1309 may be a receiving portion 1305 or a wireless power transmitter 1301. The cover 1309 can open or close the receiving space of the receiving portion 1305. At least one of the inner and outer surfaces of the cover 1309 is connected to the outer shield 1303 ) Of the same material.

The external shielding member 1303 may be a magnetic sheet including a magnetic body. The magnetic material may include at least one of an amorphous ribbon, a nano-stalin ribbon, and a silicon steel sheet. The external shielding material 1303 may be integrated with the housing of the wireless power transmitter 1301. For example, the housing may be an injection molding material including a magnetic substance of a sensor type constituting the external shielding material 1303. [

14 illustrates a wireless power transmitter in accordance with another embodiment of the present invention.

14A, the housing 1403 of the wireless power transmitter 1401 may include an insertion portion 1405 into which a wireless power receiver 1407 may be inserted. The outer surface of the housing 1403 may be surrounded by a shielding material. The shielding material may be a magnetic sheet including a magnetic material. The magnetic material may include at least one of an amorphous ribbon, a nano-stalin ribbon, and a silicon steel sheet.

14 (b), the wireless power receiver 1407 may be inserted into the insertion portion 1405 to receive wireless power from the wireless power transmitter 1401. [ The wireless power receiver 1407 may be fixed by the inserter 1405 upon charging.

Referring to FIG. 14C, the housing 1403 includes a spring (not shown) for discharging the wireless power receiver 1407 to the outside of the insertion portion 1405 when the charging of the wireless power receiver 1407 is completed ). The spring may be fixed such that the wireless power receiver 1407 is disposed within the insert 1405 when the wireless power receiver 1407 is being charged.

Claims (10)

A wireless power transmitter for transmitting wireless power to a wireless power receiver,
A control circuit for controlling said wireless power transmitter;
At least one transmit coil for transmitting the wireless power to the wireless power receiver;
An inner shielding material disposed between the transmission coil and the control circuit;
A housing including the control circuit, the inner shield, the transmitting coil, and a plurality of surfaces;
And an outer shield surrounding the other of the plurality of sides of the housing except the side in contact with the wireless power receiver. The method according to claim 1,
Wherein the shielding layer shields electromagnetic fields of other frequency bands except for the frequency band for transmitting the wireless power in a frequency band of 1 MHz or less. The method of claim 2,
The frequency band for transmitting the radio power is 110 kHz,
And the other frequency band is 120 kHz to 300 kHz. The method according to claim 1,
Wherein the shielding layer is a magnetic sheet containing a magnetic material,
Wherein the magnetic body comprises at least one of an amorphous ribbon, a nanocrystalline ribbon, and a silicon steel plate. The method according to claim 1,
Wherein the shield layer surrounds at least one of the inner and outer surfaces of the plurality of surfaces of the housing other than the surface that contacts the wireless power receiver. The method according to claim 1,
The housing
A receiving space for receiving the wireless power receiver;
And a cover capable of closing or opening the accommodation space,
Wherein the shield layer surrounds both the receiving space and the outer surface of the cover. The method according to claim 1,
Wherein the housing is integral with the shielding layer and is an injection molded object including a sendust series magnetic body constituting the shielding layer. The method according to claim 1,
Wherein the shielding layer is coated on the other side of the plurality of sides of the housing except for a side in contact with the wireless power receiver. The method according to claim 1,
The housing
An inserter capable of inserting the wireless power receiver;
And a spring for discharging the wireless power receiver to the outside of the insertion portion when charging of the wireless power receiver is completed,
Wherein the spring is fixed such that when the wireless power receiver is charging, the wireless power receiver is positioned to be located inside the insert. The method of claim 9,
Wherein the control circuit controls the spring according to whether the wireless power receiver is charged.

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