KR101833738B1 - Wireless Power Transfer System - Google Patents

Abstract

A wireless power transmission system according to an exemplary embodiment of the present invention includes a transmitter for transmitting a first power; And a receiver for receiving the first power from the transmitter, wherein the transmitter includes a transmission coil and a first temperature sensor, and when the temperature measured from the first temperature sensor is a predetermined power control request temperature, And the transmitting unit transmits the second power lower than the first power.

Description

[0001] WIRELESS POWER TRANSFER SYSTEM [0002]

The present invention relates to a wireless power transmission system.

A wireless power transfer (WPT) system is a technology that delivers power without wires through space, maximizing 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 through the magnetic flux generated thereby.

The self-resonance method is a magnetic resonance technology that uses only electric field or magnetic field without using electromagnetic wave or current. It is characterized by using a band of several tens of MHz because the distance of power transmission is several meters or more.

In this wireless power transmission system, it is important to manage the overheating problem of the system because the overheating problem of the transmitting unit for receiving power and the receiving unit for receiving power is closely related to the power transmission efficiency.

The magnetic induction method is a method of wirelessly transmitting power using two coils, including an inverter, a transformer, a rectifier, and an impedance matching stage.

Continuous impedance matching is needed to improve power efficiency when the power transfer characteristics change in the magnetic induction mode. At this time, the temperature rise of the transmitter and the receiver due to the overheating can change the characteristics of various devices, causing inconsistency of the impedance, and consequently lowering the power efficiency.

This is because impedance matching is essential for a self-resonance method in which a resonance frequency of a coil is matched to a specific frequency and power is transmitted at a corresponding frequency. However, a change in device characteristics due to overheating leads to a problem of lowering the power efficiency.

Another cause of overheating is overheating due to the eddy current due to the change of the magnetic field applied to the conductor when a foreign body is attached to the transmitter.

In addition to the internal factors of such a wireless transmission power system, there is also heat generated by the external environment.

The heat generated at the transmitter and the receiver due to the above factors may cause damage to various devices and systems.

In other words, controlling the heat generation in the wireless power transmission technology is a very important problem not only in solving the technical problem of increasing the power efficiency but also in the stable operation of the system.

In recent years, a technology has been developed in which a transmitter is provided with an overheat protection function and the receiver is overheated to transmit the low power to the transmitter, thereby controlling the heat generation. However, such a heat generation control method has a problem that it is difficult to control the overheating of the transmission part side, and in the self resonance method of transmitting a relatively high power compared to the magnetic induction method, it is more important to control the overheating of the transmission part.

In addition, when power is transmitted to a receiver located at a distance of several meters, or when a plurality of receivers receive power through one transmitter, it is important to control the heat generated by the transmitter rather than to the receiver, .

In addition, when the transmitter reaches the overheating state, the heat generation amplification phenomenon occurs due to the heat weighting phenomenon. Therefore, there is a problem that it is very difficult to manage the system below the expected temperature after reaching the overheated state.

A wireless power transmission system according to an embodiment of the present invention provides a wireless power transmission system capable of solving an amplification phenomenon due to a heat load due to a state where a transmitter is in an overheated state.

Also, the wireless power transmission system according to an embodiment of the present invention provides a wireless power transmission system capable of controlling the heat generation by measuring both the surface temperature of the transmitter and the surface temperature of the receiver adjacent to the transmitter.

The wireless power transmission system according to an embodiment of the present invention also provides a wireless power transmission system that can simplify the system and improve the compatibility between the transmitter and the receiver.

A wireless power transmission system according to an exemplary embodiment of the present invention includes a transmitter for transmitting a first power; And a receiver for receiving the first power from the transmitter, wherein the transmitter includes a transmission coil and a first temperature sensor, and when the temperature measured from the first temperature sensor is a predetermined power control request temperature, And the transmitting unit transmits the second power lower than the first power.

In a wireless power transmission system according to an embodiment of the present invention, the first temperature sensor is disposed on the transmission coil.

In a wireless power transmission system according to an embodiment of the present invention, the wireless power transmission system transmits power in a magnetic induction manner.

In a wireless power transmission system according to an embodiment of the present invention, the wireless power transmission system transmits power in a self-resonant manner.

In the wireless power transmission system according to an embodiment of the present invention, a temperature at which the transmitter is overheated is defined as a critical temperature value, a temperature set according to the power transmission efficiency of the transmitter is defined as a expected temperature, Wherein the threshold temperature value is lower than the expected temperature value.

In the wireless power transmission system according to the embodiment of the present invention, the transmitter includes a substrate including a wireless power controller for controlling power transmitted from the transmitter, and a second temperature sensor. And a ferrite disposed on the substrate, wherein the transmission coil is disposed on the ferrite, the second temperature sensor measures a temperature of the substrate, and the radio power controller controls the second temperature sensor And controls power transmitted from the transmitter if the measured temperature is a predetermined temperature.

In the wireless power transmission system according to an embodiment of the present invention, the transmitter includes an input power unit; A switch mode power supply for receiving power from the input power supply; A power driver receiving power from the switch mode power supply and supplying power to the transmit coil; A wireless power control unit for controlling the switch mode power supply and the power driver according to a temperature measured by the first temperature sensor; And a decoder for decoding the signal received from the receiver and providing the decoded signal to the radio power controller.

A power transmission method of a wireless power transmission system according to an embodiment of the present invention is a power transmission method of a wireless power transmission system including a transmission unit and a reception unit, One sensing one of the others; The receiving unit requesting a first power transmission to the transmitting unit; Measuring a temperature on a transmission coil included in the transmission unit; And transmitting the second power lower than the first power when the measured temperature corresponds to a predetermined power control required temperature.

In a power transmission method of a wireless power transmission system according to an embodiment of the present invention, a temperature at which the transmitter is overheated is defined as a critical temperature value, a temperature set according to a power transmission efficiency of the transmitter is defined as a expected temperature, Wherein the control request temperature is lower than the threshold temperature value and higher than the expected temperature.

In the power transmission method of the wireless power transmission system according to the embodiment of the present invention, when the measured temperature is the power control request temperature, when the receiver requests the transmitter for the first power transmission, And transmits the second power to the receiver with a priority.

In the power transmission method of a wireless power transmission system according to an embodiment of the present invention, the power transmission method of the wireless power transmission system is a method of power transmission in a wireless power transmission system according to a magnetic induction method.

In the power transmission method of the wireless power transmission system according to the embodiment of the present invention, the power transmission method of the wireless power transmission system is a self-resonant method.
A wireless power transmitter according to an embodiment of the present invention includes: a substrate; A shielding portion disposed on the substrate; A first coil, a second coil, and a third coil disposed on the shield; A first temperature sensor disposed in a region overlapping the hollow portion of the first coil; A second temperature sensor disposed in a region overlapping the hollow portion of the second coil; A third temperature sensor disposed in a region overlapping the hollow portion of the third coil; A first connection wiring connected to the first temperature sensor and disposed under the first coil; A second connection wiring connected to the second temperature sensor and disposed under the second coil; And a third connection wiring connected to the third temperature sensor and disposed under the third coil, wherein the third coil is connected to the first coil and the second coil on the first coil and the second coil, And the first temperature sensor and the second temperature sensor may be disposed in an area not overlapped with the third coil.
Also, in the wireless power transmitter according to an embodiment of the present invention, the shield may include a groove provided for the temperature measurement of the first to third temperature sensors.
Further, in the wireless power transmitter according to the embodiment of the present invention, the groove may include: a first groove for the first temperature sensor; A second groove for the second temperature sensor; And a third groove for the third temperature sensor.
Further, in the wireless power transmitter according to the embodiment of the present invention, the first groove is disposed in a region overlapping the hollow portion of the first coil, and the second groove is disposed in a region overlapping the hollow portion of the second coil And the third groove may be disposed in a region overlapping the hollow portion of the third coil.
Further, in the wireless power transmitter according to the embodiment of the present invention, the first groove is disposed in a region corresponding to the first temperature sensor, the second groove is disposed in a region corresponding to the second temperature sensor, And the third groove may be disposed in a region corresponding to the third temperature sensor.
Also, in the wireless power transmitter according to the embodiment of the present invention, the substrate may include a wireless power controller.
Also, in the wireless power transmitter according to the embodiment of the present invention, the outer portion of the third coil may be disposed in a region where the hollow portion of the first coil and the hollow portion of the second coil are in contact with each other.
Further, in the wireless power transmitter according to the embodiment of the present invention, the third temperature sensor may be disposed in an area that is not overlapped with the first coil and the second coil.
In addition, the wireless power transmitter according to the embodiment of the present invention may further include a case in which the first coil, the second coil, and the third coil are housed.
Further, the wireless power transmitter according to the embodiment of the present invention may further include a case in which the shielding portion is housed.

The wireless power transmission system according to the embodiment of the present invention can manage the heat generation of the transmitter before the transmitter reaches the overheated state to prevent the heat amplification phenomenon due to the heat weighting phenomenon, The surface temperature of the transmitting unit and the surface temperature of the receiving unit adjacent to the transmitting unit can be measured to control the heat generation. In addition, in the multi-radio power transmission system having one transmitter and a plurality of receivers, It is possible to manage the heat generation of the transmitter which generates a relatively large amount of power and to control the surface temperature of the transmitter so that it is not necessary to provide a separate temperature sensor in the receiver, Since power control is unnecessary, the system can be simplified and compatibility can be improved.

1 is a block diagram illustrating a wireless power transmission system 10 in accordance with an embodiment of the present invention.
2 is a perspective view of a transmitting apparatus according to an embodiment of the present invention;
Fig. 3A shows one transmission coil and a temperature sensor. Fig.
Figs. 3B and 3C are cross-sectional views taken along line AB of Fig. 3A. Fig.
Figures 4 and 5 show a plurality of transmit coils.
6 and 7 are signal flow diagrams illustrating the operation of a wireless power transmission system in accordance with an embodiment of the present invention.
8 is a graph showing the relationship between the temperature and the amount of transmission power and time.

Hereinafter, a wireless power transmission system according to an embodiment of the present invention will be described in detail with reference to the accompanying 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 use a variety of frequency bands from low frequency (50 kHz) to high frequency (15 MHz) selectively for wireless power transmission, and it is necessary to support a communication system capable of exchanging 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 household appliance industry, an electric car industry, a medical device industry, and a robot industry.

An embodiment may consider a system capable of transmitting power to one or more multiple devices using a single transmit coil provided with the device.

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 multiple-device power receivers in the magnetic field area and manages the entire system.

Receiver (Wireless Power Transfer System-Deivce) : A device that receives wireless power transmission from a power transmitter within a magnetic field region.

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.

<Configuration of Wireless Power Transmission System>

1 is a block diagram illustrating a wireless power transmission system according to an embodiment of the present invention.

Referring to FIG. 1, a wireless power transmission system 10 according to an embodiment of the present invention may include a transmitter 100 for transmitting power wirelessly and a receiver 200 for receiving power from the transmitter 100 have.

The transmitter 100 includes an input power unit 110, a switching mode power supply (SMPS) 120, a power driver 130, a wireless power controller 140, a temperature sensor 160, And may include a transmitter coil 170.

The input power supply unit 110 supplies power to the switch mode power supply 120, which is a source of energy that is the basis of the transmitted power.

The switch mode power supply 120 may be different in type and technique from standard to standard.

The switch mode power supply 120 converts a DC input voltage into a square wave voltage by using a semiconductor device such as a power MOSFET as a switch and then obtains a DC output voltage controlled through a filter. It can do the conversion.

The switch mode power supply 120 includes a DC-DC converter for converting the DC input voltage obtained from the AC input power source through the input rectifying smoothing circuit into a DC output voltage, a feedback control circuit for stabilizing the output voltage, an overvoltage and overcurrent protection circuit .

The power driver 130 receives power from the switch mode power supply 120 and supplies power to the transmission coil 170 under the control of the wireless power control unit 140.

The wireless power control unit 140 may control the switch mode power supply 120 and the power driver 130 based on the signal received from the decoder 150 and the signal received from the temperature sensor 160. [

The decoder 150 may decode the received signal received from the receiver 200 through the antenna and supply the decoded signal to the wireless power controller 140.

The temperature sensor 160 may measure the temperature of the transmitter 100 and transmit the result to the wireless power controller 140.

The coil 170 may include at least one of an induction coil and a resonance coil.

When the wireless power transmission system 10 transmits power only in a self-induction manner, the coil 170 may include only the induction coil, and when power is transmitted only by the self-resonance method, the coil 170 may include only the resonance coil, In the case of transmitting power by using a combination of the magnetic induction type and the magnetic resonance type, both the induction coil and the resonance coil can be provided.

The receiving unit 200 may include a load 210, a battery management unit (BMIC) 220, a DC-DC converter 230, a smoothing circuit 240, a rectifying unit 250, and a receiving coil 260 .

The receiving coil 260 may receive power through a magnetic induction method or a self-resonance method. As described above, the receiving coil 260 may include at least one of an induction coil and a resonance coil according to a power reception scheme.

The rectifying unit 250 may convert the power supplied from the receiving coil 260, which has received the AC power, to DC power.

The rectifier 250 may include one or more silicon diodes, and may be configured as a bridge diode.

Since the rectifying unit 250 can perform a rectifying function to convert received AC power into DC power and the rectifying function allows a current to pass only in one direction, the rectifying unit 250 has a small forward resistance, The resistance is large enough to allow current to flow in only one direction. At this time, power is proportional to voltage or current, so it is assumed that power, voltage, and current are the same concept for convenience.

The smoothing circuit 240 can output the complete DC power by removing the ripple component from the DC power output from the rectifying unit 250, and can be configured as a smoothing capacitor.

The DC-DC converter 230 may output a DC voltage suitable for the battery management unit 220 to operate using the DC voltage output from the smoothing circuit 240, and may output the DC voltage output from the smoothing circuit 240 to the AC Voltage, and then, the converted AC voltage is stepped up or stepped down and rectified to output a DC voltage suitable for the battery management unit 220 to operate.

Meanwhile, a switching regulator or a linear regulator may be used as the DC-DC converter 230.

A linear regulator is a converter that receives an input voltage and outputs an output voltage as needed, while the remaining voltage is discharged as heat. A switching regulator uses a pulse width modulation (PWM) It is an adjustable converter.

The battery management unit 220 may regulate the DC power output from the DC-DC converter 230 and provide the regulated DC power to the load 210. The load 210 may refer to a battery, and the battery management unit 220 may be included within the load 210.

The load 210 may vary the amount of current charged according to the DC voltage applied to both ends of the load 210.

The battery management unit 220 may adjust the DC power to charge the load 210 with a constant DC current and provide the load 210 with the DC power.

3A and 3B are views showing a transmission coil and a temperature sensor, FIGS. 3B and 3C are cross-sectional views taken along line AB of FIG. 3A, and FIGS. 4 and 5 are cross- 5 is a diagram showing a plurality of transmission coils.

Hereinafter, the arrangement relationship and the role of the temperature sensor 160 will be described with reference to FIGS. 2 to 3C.

The transmission unit 100 according to the embodiment of the present invention includes a substrate 190 including a case 101, a transmission coil 170, a temperature sensor 160, a ferrite 180 for shielding, and a radio power control unit 140. [ . &Lt; / RTI &gt;

The ferrite 180 may be made of a high-frequency magnetic material having ferric oxide as its main raw material.

A magnetic shielding effect can be obtained by using the ferrite 180. [

The present invention is not limited to the ferrite 180. The present invention may be applied to the transmission coil 170 of the transmission unit 100 as well as the transmission coil 170 of the reception unit 200 It is required to satisfy international EMI (Electro-Magnetic Interference) and EMC (Electro-Magnetic Copability) EMF (electromagnetic field) regulations.

On the other hand, the ferrite 180 may be formed with a receiving groove (not shown) for receiving the transmitting coil 170.

When the transmission coil 170 is inserted into the receiving groove of the ferrite 180, the entire thickness of the transmitting portion 100 can be reduced. The receiving coil 260 of the receiving unit 200 may also be inserted into the magnetic body included in the receiving unit 200.

The case 101 may receive a substrate 190 including a transmission coil 170, a temperature sensor 160, a ferrite 180, and a radio power control unit 140.

The transmission coil 170 and the temperature sensor 160 and the substrate 190 may be disposed with the ferrite 180 interposed therebetween and the transmission coil 170 and the temperature sensor 160 may be disposed between the control unit 140, respectively.

The transmission coil 170 includes first and second lead wires 171 and 172 extended from both ends so that the transmission coil 170 is connected to the first and second lead wires 171 and 172 (Not shown).

The temperature sensor 160 may be connected to the substrate 190 through a connection wiring 161.

As shown in FIG. 3B, the connection wiring 161 may be drawn to the upper surface of the transmission coil 160.

When the number of the temperature sensors 160 disposed on the transmission coil 160 increases or the thickness of the connection wiring 161 according to the product of the temperature sensor 160 increases, The magnetic field directed to the upper surface of the transmission coil 160 can be influenced. Therefore, in order to minimize the influence, it can be drawn to the lower surface of the transmission coil 160 as shown in FIG. 3C.

In addition, the ferrite 180 may have grooves for accommodating the connection wires 161 connected to the temperature sensor 160 and the temperature sensor 160.

When the temperature sensor 160 and the connection wiring 161 are inserted into the grooves of the ferrite 180, the overall thickness of the transmission part 100 is reduced.

As the temperature sensor 160, a bimetal or a thermistor may be used.

Especially, the thermistor is a device whose electric resistance changes according to temperature, and has advantages of high reliability, robustness, fast response and low cost.

The temperature sensor 160 using the thermistor can change the resistance value according to the change of the ambient temperature and the degree of change of the current value can be sensed by the wireless power control unit 140 of the substrate 190. [

The radio power controller 140 may adjust the amount of power to be supplied to the receiver 200 based on the ambient temperature sensed by the temperature sensor 160.

The temperature sensor 160 can measure the temperature around the transmission coil 170 of the transmission unit 100 and the temperature of the upper surface of the transmission unit 100.

Also, in the magnetic induction method, since the transmitter 100 and the receiver 200 perform wireless power transmission within a distance of a few millimeters, the temperature of the upper surface of the transmitter 100 is measured using the temperature sensor 160, The temperature of the upper surface of the receiver 200 facing the upper surface of the transmitter 100 can be measured together.

That is, the temperature of the upper surface of the transmitter 100 may be determined to be the temperature of the upper surface of the receiver 200. Therefore, the temperature sensor 160 can measure the temperature of the receiving unit 200 as well as the transmitting unit 100.

 The wireless power control unit 140 can control the amount of power transmission based on the measured ambient temperature from the temperature sensor 160.

The transmission coil 100 need not necessarily be provided, but may be constituted by a plurality of transmission coils 100 as shown in FIG. 4 and FIG.

As shown in FIG. 4, three transmission coils 100 may be provided and overlapped, and two transmission coils 100 are provided as shown in FIG. 5, but they may not overlap each other.

When a plurality of transmission coils 100 are provided and overlapped, the overlapped area is determined in consideration of the deviation of the magnetic flux density.

If the overlapping area is too large or too small, it is undesirable. If the area of the coil is 100, the overlapped area may be suitably about 20 to 80. However, the present invention is not limited to this, and may vary depending on the applied product power transmission method.

At least one temperature sensor 160 may be provided in at least one of the areas A, B, and C of the transmission coil 100 to measure the temperature of the periphery of the transmission coil 100 through the temperature sensor 160 .

For example, when three temperature sensors 160 are provided in the areas A, B, and C, power is controlled using the temperature average value measured by the three temperature sensors 160, or three temperature sensors 160 The power can be controlled by using the maximum value of the temperature measured by the temperature measuring unit 160.

On the other hand, a separate temperature sensor (not shown) may be provided on the substrate 190.

If the temperature sensor 160 located at the periphery of the transmission coil 100 is referred to as a first temperature sensor, the temperature sensor provided on the substrate 190 may be referred to as a second temperature sensor.

The second temperature sensor can measure the degree of heat generation on the substrate 190 and the wireless power control unit 140 can measure the temperature of the substrate 190 through the temperature measured from the second temperature sensor separately from the first temperature sensor 160. [ When it is judged that the peripheral portion is overheated, the power transmission amount can be adjusted.

The reason for including both the first and second temperature sensors as described above is that the cause of the heat generation in the peripheral portion of the substrate 190 and the cause of the heat generation in the peripheral portion of the transmission coil 170 may be different from each other.

The first temperature sensor 160 is connected to the upper end of the transmission coil 170 and the upper surface of the transmission unit 100 as well as the upper surface of the transmission unit 100, The temperature of the receiving unit 200 adjacent to the upper surface can also be measured.

Although the shape of the transmitting coil 170 is shown as having a rounded shape and an overall shape as a whole, it is not limited thereto and may be a different shape such as a circular shape.

&Lt; Operation relationship of wireless power transmission system >

6 and 7 are signal flow diagrams illustrating the operation of a wireless power transmission system according to an embodiment of the present invention.

The first step is the sensing step S100.

When the receiving unit 200 approaches the charging area of the transmitting unit 100, the transmitting unit 100 senses the receiving unit 200 or conversely the receiving unit 200 senses the transmitting unit 100 to transmit wireless power You can start.

The sensing step S100 may include a selection step of sensing the receiving unit 200 in a detailed step, a ping receiving a packet, a unique ID Id and an extended ID for the receiving unit 200, And identification and configuration steps for receiving information.

The second step is the power request step S200.

A case where the receiving unit 200 requests the transmitting unit 100 to transmit the first power may include a state of the receiving unit 200, that is, a state of charge of the battery of the receiving unit 200, a state of the receiving unit 200 itself, The amount of power consumed by the battery, the amount of power consumed, and the charging rate of the battery. Therefore, the transmitter 100 can request a specific amount of power. Accordingly, even when the first power amount requested by the receiver 200 exceeds the transmittable power amount of the transmitter 100, the amount of electric power actually transmitted by the transmitter 100 can be reduced, Can not exceed the maximum transmission power of the base station 100. [

And a third step of measuring the degree of heat generation (S300).

8 is a graph showing the relationship between the temperature and the amount of transmission power and time.

The critical temperature value, the expected temperature, and the power control required temperature are defined with reference to FIG.

A second temperature (expected temperature) lower than the first temperature and considering the power transmission efficiency, and a second temperature (expected temperature) lower than the first temperature, wherein the first temperature (critical temperature value; (Power control required temperature) can be defined.

Also, the first to third temperatures may be specified to a specific range other than a specific temperature value.

The first temperature sensor 160 may measure the temperature around the transmission coil 170 and provide the measured temperature value to the radio power controller 140.

The fourth step is the power control step (S400).

When the temperature measured by the first temperature sensor 160 corresponds to a second temperature other than the first temperature, the transmitting unit 100 can transmit the first power requested by the receiving unit 200. However, when the temperature measured by the first temperature sensor 160 corresponds to the third temperature, the wireless power controller 140 controls the switch mode power supply 120 and the power driver 130 Can be controlled.

That is, regardless of the amount of power required by the receiver 200, the power can be controlled by raising the priority of the temperature around the transmission coil 170 of the transmission unit 100.

However, the second power described above may be a specific range of power rather than a specific power value.

Also, as shown in the graph of FIG. 8, the second power provided to the receiver 200 may vary depending on the degree of heat generation of the wireless power transmission system 10.

On the other hand, the reason why the transmitter 100 controls the power when the temperature is not the first temperature, which is the overheat temperature, is as follows.

If the transmitter 100 is already overheated, an impedance mismatch occurs between the transmitter 100 and the receiver 200, resulting in an increase in power consumption for impedance matching and a corresponding heat generation.

This is because it is difficult to get out of the overheated state quickly even if the amount of electric power for transmitting and amplifying the heat amplification phenomenon due to the weighting effect of the heat is greatly reduced.

That is, it is difficult to lower the temperature of the wireless power transmission system 10 to an appropriate temperature unless the charging operation is temporarily stopped when the battery is once overheated. Accordingly, when the temperature measured by the first temperature sensor 160 reaches the overheat temperature, that is, the third temperature before the temperature reaches the first temperature, which is the critical temperature value, the power is controlled to allow the wireless power transmission system 10 to operate stably .

The fifth step is a charging completion judgment step (S500).

When the charging of the receiving unit 200 is completed, the power transmission is stopped. However, if the charging of the receiving unit 200 is not completed, the amount of power requested by the receiving unit 200 and the temperature of the current transmitting unit 100 are determined, The step of controlling the amount of power can be repeated.

The wireless power transmission system 10 according to the embodiment of the present invention has the following effects.

First, before the transmitter 100 reaches the overheated state, the transmitter 100 may manage the heat generation, thereby preventing the heat amplification due to the heat load.

Secondly, a temperature sensor 160 is provided on the transmission coil 170 side of the transmitter 100 so that the surface temperature of the transmitter 100 and the temperature of the receiver 200 adjacent to the transmitter 100, as well as the transmit coil 170, It is possible to control the heat generation by simultaneously measuring the surface temperature of the heater.

Third, there is an effect that it is easy to manage the heat generation of the transmitter 100, which generates a relatively large amount of power in a multi-radio power transmission system having one transmitter 100 and a plurality of receivers 200.

Fourth, by managing the surface temperature of the transmitter 100, there is no need to provide a separate temperature sensor in the receiver 200, and it is not necessary to control the power according to the communication between the transmitter and the temperature sensor separately provided in the receiver. Therefore, the system can be simplified and the compatibility between the transmitter 100 and the receiver 200 can be improved.

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.

10 Wireless Power Transmission System
100 transmitter
110 Input power section
120 Switch Mode Power Supply
130 power driver
140 wireless power control unit
150 decoder
160 first temperature sensor
161 Connection wiring
170 transmission coil
171 First Drawing Line
172 2nd outgoing line
180 ferrite
190 substrate
200 Receiver
210 load
220 Battery management section
230 DC-DC Converter
240 smoothing circuit
250 rectification part
260 receiving coil

Claims (12)

Board;
A shielding portion disposed on the substrate;
A first coil, a second coil, and a third coil disposed on the shield;
A first temperature sensor disposed in a region overlapping the hollow portion of the first coil;
A second temperature sensor disposed in a region overlapping the hollow portion of the second coil;
A third temperature sensor disposed in a region overlapping the hollow portion of the third coil;
A first connection wiring connected to the first temperature sensor and disposed under the first coil;
A second connection wiring connected to the second temperature sensor and disposed under the second coil; And
And a third connection wiring connected to the third temperature sensor and disposed under the third coil,
The third coil is arranged to overlap the first coil and the second coil on the first coil and the second coil,
Wherein the first temperature sensor and the second temperature sensor are disposed in an area not overlapping with the third coil. delete The method according to claim 1,
The shielding portion
Wherein the first temperature sensor to the third temperature sensor include a groove provided to allow temperature measurement. The method of claim 3,
The groove
A first groove for the first temperature sensor;
A second groove for the second temperature sensor; And
And a third groove for the third temperature sensor. 5. The method of claim 4,
Wherein the first groove is disposed in a region overlapping the hollow portion of the first coil,
The second groove is disposed in a region overlapping the hollow portion of the second coil,
And the third groove is disposed in a region overlapping the hollow portion of the third coil. 6. The method of claim 5,
Wherein the first groove is disposed in a region corresponding to the first temperature sensor,
The second groove is disposed in a region corresponding to the second temperature sensor,
And the third groove is disposed in a region corresponding to the third temperature sensor. delete The method according to claim 1,
Wherein the substrate comprises a radio power controller. The method according to claim 1,
And an outer portion of the third coil is disposed in a region of the hollow portion of the first coil and the hollow portion of the second coil. The method according to claim 1,
And the third temperature sensor is disposed in an area not overlapping the first coil and the second coil. The method according to claim 1,
And a case in which the first coil, the second coil, and the third coil are housed. The method according to claim 1,
And a case in which the shield is received.

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