KR20200077816A - Wireless charging apparatus and the operation method - Google Patents

Abstract

The present invention provides a wireless charging device which easily changes a wireless charging frequency. The wireless charging device comprises: a converter converting input power into set direct current (DC) power; a DC measuring unit measuring a current and voltage of the DC power; an inverter converting the DC power into alternating current (AC) power for wireless charging and supplying the same to a transmission antenna; an antenna current measuring unit measuring an antenna current applied to the transmission antenna; an impedance matching unit adjusting a resonance frequency of the AC power to a set wireless charging frequency by varying impedance of the transmission antenna; and a control unit controlling at least one operation of the inverter and the impedance matching unit when at least one change in the DC power and the AC power occurs based on the current and voltage of the DC power and the antenna current.

Description

Wireless charging apparatus and the operation method

The present invention relates to a wireless charging device and a method for operating the same, and more particularly, to a wireless charging device and an operating method for easily changing the wireless charging frequency according to changes in the wireless charging environment.

With the development of electric, electronic, and information and communication technologies, the spread of mobile devices such as smart phones, tablet PCs, and wearable devices has been rapidly spread in recent years.

In addition, as IT services using mobile devices have dramatically increased, it has become a necessity to occupy a part of life because users can conveniently use various services anytime and anywhere.

Due to this, users spend more time using mobile devices and the frequency of charging increases due to the limitation of battery capacity.

However, frequent battery replacement and charging for power supply have become a major factor that degrades the convenience of using a user's mobile device.

Therefore, in recent years, cases of applying wireless charging technology as a method for increasing charging convenience of electronic devices such as mobile devices are increasing.

In a typical conventional commercial 1:1 wireless charging, since the wireless charging transmitter and receiver are charged in a contact form within a few mm, the wireless charging environment can be kept constant.

However, in a next-generation wireless charging system that can wirelessly charge multiple devices over a long distance, such as resonant wireless charging, there is a high possibility of changes in the wireless charging environment, such as a change in the wireless charging distance and a change in the number of wireless chargers. It may affect the wireless charging system.

Recently, research is underway to detect changes in the wireless charging environment and to maintain optimal wireless charging efficiency at all times.

Domestic Publication No. 2016-0085530 (2016.07.18)

An object of the present invention is to provide a wireless charging device and an operation method of the wireless charging frequency that can be easily changed according to changes in the wireless charging environment.

In addition, an object of the present invention is to provide a wireless charging device and an operation method for maintaining an optimal wireless charging efficiency and improving efficiency when detecting a change in the wireless charging environment.

The objects of the present invention are not limited to the objects mentioned above, and other objects and advantages of the present invention not mentioned can be understood by the following description, and will be more clearly understood by the embodiments of the present invention. In addition, it will be readily appreciated that the objects and advantages of the present invention can be realized by means of the appended claims and combinations thereof.

The wireless charging device according to the present invention, a converter for converting the input power to a set dc power, a dc measuring unit for measuring the current and voltage of the dc power, and converts the dc power into ac power for wireless charging and transmit antenna Inverter supplied to the antenna, an antenna current measuring unit for measuring the antenna current applied to the transmitting antenna, the impedance matching unit to vary the impedance of the transmitting antenna to set the resonant frequency of the ac power to the set wireless charging frequency and the dc power If it is determined that at least one change of the dc power source and the ac power source has occurred based on the current and voltage of the antenna current, the controller may include a control unit that controls operation of at least one of the inverter and the impedance matching unit. have.

The converter may be a dc-dc converter that outputs the dc power that has boosted or reduced the input power.

The dc measuring unit may measure the current and voltage of the dc power input to the inverter.

The antenna current measurement unit may measure the antenna current for the ac power source matched by the impedance matching unit.

When it is determined that the current and voltage of the dc power supply have changed, the controller may control the operation of the inverter to control the impedance matching unit such that the resonance frequency of the ac power supply and the ac power supply is varied.

When it is determined that the change in the antenna current has occurred, the control unit may control only the impedance matching unit such that the resonance frequency of the ac power source is variable.

The wireless charging apparatus according to the present invention may further include an in-band communication unit communicating at the wireless charging frequency during wireless charging and an out-band communication unit communicating at a frequency other than the wireless charging frequency during wireless charging. .

Method of operation of the wireless charging device according to the present invention, the converter converts the input power to a set dc power, the dc measuring unit measures the current and voltage of the dc power, the inverter for wireless charging the dc power converting to ac power and supplying it to a transmitting antenna, measuring an antenna current applied by the antenna current measuring unit to the transmitting antenna, and changing an impedance of the transmitting antenna by an impedance matching unit to set a resonance frequency of the ac power Transmitting according to the charging frequency, the control unit determining that at least one change in the dc power supply and the ac power supply is generated based on the current and voltage of the dc power supply and the antenna current, and the control unit and the dc power supply And when it is determined that at least one of the dc power sources has changed, controlling the operation of at least one of the inverter and the impedance matching unit to vary the resonance frequency of the ac power source.

The wireless charging apparatus and the operation method according to the present invention have the advantage of being able to detect changes in the wireless charging environment.

In addition, the wireless charging apparatus and method of operating the same according to the present invention have an advantage of maximizing wireless charging efficiency by varying the resonance frequency of the ac power transmitted from the transmitting antenna when detecting a change in the wireless charging environment.

In addition to the above-described effects, the concrete effects of the present invention will be described together while describing the specific matters for carrying out the present invention.

1 is a system diagram briefly showing a wireless charging system according to the present invention.
2 is a control block diagram showing a control configuration of a wireless charging device according to the present invention.
3 is a flowchart illustrating an operation method of a wireless charging device according to the present invention.

It should be noted that in the following description, only parts necessary for understanding the embodiments of the present invention are described, and descriptions of other parts will be omitted so as not to distract the subject matter of the present invention.

The terms or words used in the present specification and claims described below should not be interpreted as being limited to ordinary or lexical meanings, and the inventor is appropriate as a concept of terms to describe his or her invention in the best way. It should be interpreted as a meaning and a concept consistent with the technical idea of the present invention based on the principle that it can be defined as such. Therefore, the configuration shown in the embodiments and drawings described in this specification is only a preferred embodiment of the present invention, and does not represent all of the technical spirit of the present invention, and various equivalents that can replace them at the time of this application It should be understood that there may be and variations.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a system diagram briefly showing a wireless charging system according to the present invention, and FIG. 2 is a control block diagram showing a control configuration of the wireless charging device according to the present invention.

1 and 2, the wireless charging system 100 may include a wireless charging receiver 110 and a wireless charging device 150.

The wireless charging receiver 110 may perform wireless charging by receiving the wireless charging signal PT transmitted from the wireless charging device 150.

The wireless charging receiver 110 may be a device capable of wireless charging, such as a mobile terminal, a smart phone, a tablet PC, and a wearable device, but is not limited thereto.

The wireless charging device 150 includes a power supply unit 152, a converter 154, a dc measurement unit 156, an inverter 158, a transmission antenna 160, an antenna current measurement unit 162, an impedance matching unit 164, It may include an in-band communication unit 166, an out-band communication unit 168 and the control unit 170.

The power unit 152 may supply power Vin for generating the wireless charging signal PT to the converter 154 and the control unit 170.

Here, the power source Vin may be a battery power source, but is not limited thereto.

The converter 154 may convert the power supply Vin input from the power supply unit 152 into a set dc power supply Vdc. At this time, the converter 154 may be a dc-dc converter that outputs a dc power supply (Vdc) that boosts or depressurizes the power supply (Vin), but is not limited thereto.

If the power supply Vin is an AC voltage, an ac-dc converter that converts power supplied to the converter 154 into direct current power may be disposed at the front end of the converter 154, but is not limited thereto.

The dc measurement unit 156 may measure the voltage and current of the dc power supply (Vdc) output from the converter 154. That is, the dc measuring unit 156 may measure the voltage (V_value) and the current (I_value) of the dc power supply (Vdc) before the dc power supply (Vdc) output from the converter 154 is input to the inverter 158. And there is no limitation.

The inverter 158 may convert the dc power (Vdc) output to the converter 154 to an ac power (Vac) for wireless charging and supply it to the transmitting antenna 160.

At this time, the inverter 158 may be implemented with a plurality of switch elements (not shown), and may output ac power (Vac) by switching operation under the control of the controller 170.

The transmitting antenna 160 may transmit the wireless charging signal PT corresponding to the ac power Vac applied from the inverter 158 to the wireless charging receiver 110.

The antenna current measuring unit 162 may measure the antenna current (Ia_value) for the ac power supply (Vac) applied to the transmitting antenna 160.

The impedance matching unit 164 may change the impedance so that the resonance frequency of the ac power source Vac is varied so that the wireless charging signal PT corresponding to the wireless charging frequency set by the transmitting antenna 160 is transmitted.

In this case, the impedance matching unit 164 may be implemented by, for example, an LC series resonance circuit or an LC parallel resonance circuit.

In addition, the impedance matching unit 164 may select a plurality of inductors (L) or capacitors (C) under the control of the control unit 170 to vary the impedance, but is not limited thereto.

The in-band communication unit 166 may communicate with the wireless charging receiver 110 during wireless charging, at a wireless charging frequency, and the out-band communication unit 168 may wirelessly charge with the wireless charging receiver 110 during wireless charging. Communication can be performed at other frequencies.

The in-band communication unit 166 and the out-band communication unit 168 may selectively perform wireless communication with the wireless charging receiver 110 under the control of the control unit 170, but are not limited thereto.

The control unit 170 includes a power supply unit 152, a converter 154, a dc measurement unit 156, an inverter 158, a transmission antenna 160, an antenna current measurement unit 162, an impedance matching unit 164, In- The operation of the band communication unit 166 and the out-band communication unit 168 can be controlled.

When performing wireless charging with the wireless communication receiver 110, the control unit 170 includes the voltage (V_value) and current (I_value) of the dc power supply (Vdc) measured by the dc measurement unit 156, and the antenna current measurement unit ( The antenna current (Ia_value) measured in 162 may be received.

Thereafter, the controller 170 may determine whether at least one of the voltage V_value and the current I_value of the dc power supply Vdc and the antenna current Ia_value is changed.

That is, the controller 170 may determine whether at least one of the voltage (V_value) and the current (I_value) of the dc power supply (Vdc) and the antenna current (Ia_value) is changed to determine whether the wireless charging environment is changed. have.

The controller 170 may compare the voltage (V_value) and current (I_value) of the dc power supply (Vdc) with the previous voltage and previous current of the previous dc power supply to determine whether the dc power supply (Vdc) has changed.

At this time, if it is determined that the voltage V_value and the current I_value of the dc power supply Vdc have changed, the controller 170 controls the operation of the inverter 158 to vary the ac power supply Vac, and the ac power supply. The impedance of the impedance matching unit 164 may be controlled such that the resonance frequency of (Vac) is variable.

In addition, the control unit 170 may determine whether the antenna current (Ia_value) is changed by comparing the antenna current (Ia_value) with the previous antenna current.

If it is determined that a change in the antenna current Ia_value has occurred, the controller 170 can control only the impedance matching unit 164 such that the resonance frequency of the antenna current Ia_value is variable.

As described above, when it is determined that the change of the voltage (V_value) and the current (I_value) of the dc power supply (Vdc) and the antenna current (Ia_value) has occurred, the wireless floor device 150 according to the present invention changes the wireless charging environment. By sensing as and varying the resonance frequency of the transmitting antenna 160, there is an advantage that can increase the wireless charging efficiency in the wireless charging receiver (110).

3 is a flowchart illustrating an operation method of a wireless charging device according to the present invention.

Referring to FIG. 3, the converter 154 of the wireless charging device 150 may convert the power Vin input from the power supply unit 152 into a set dc power Vdc (S210).

The dc measuring unit 156 of the wireless charging device 150 may measure the current (I_value) and voltage (V_value) of the dc power supply (Vdc) output from the converter 154 (S220).

Here, the dc measurement unit 156 may measure the current (I_value) and voltage (V_value) of the dc power supply (Vdc) applied to the inverter 158, but is not limited thereto.

The inverter 158 of the wireless charging device 150 may convert dc power (Vdc) into ac power (Vac) for wireless charging and supply it to the transmitting antenna 160 (S230).

The antenna current measuring unit 162 of the wireless charging device 150 may measure the antenna current (Ia_value) applied to the transmitting antenna 160 (S240).

The impedance matching unit 164 of the wireless charging device 150 may vary the impedance of the transmitting antenna 160 and transmit the transmission frequency while setting the resonance frequency of the ac power source Vac to the set wireless charging frequency (S250).

The control unit 170 of the wireless charging device 150 includes the voltage (V_value) and current (I_value) of the dc power supply (Vdc) measured by the dc measurement unit 156, and the antenna current measured by the antenna current measurement unit 162 Based on (Ia_value), it may be determined whether at least one of the dc power supply (Vdc) and the ac power supply (Vac) has changed (S260).

When it is determined that the voltage V_value and the current I_value of the DC power supply VDC have changed, the controller 170 of the wireless charging device 150 controls the operation of the inverter 158 to control the AC power supply Vac. Variable, the impedance of the impedance matching unit 164 can be controlled to be variable so that the resonant frequency of the ac power supply (Vac) is variable, and when it is determined that a change in the antenna current (Ia_value) has occurred, the resonance of the antenna current (Ia_value) Only the impedance matching unit 164 may be controlled such that the frequency is variable (S270).

As described above, when it is determined that the change of the voltage (V_value) and the current (I_value) of the dc power supply (Vdc) and the antenna current (Ia_value) has occurred, the wireless floor device 150 according to the present invention changes the wireless charging environment. By sensing as and varying the resonance frequency of the transmitting antenna 160, there is an advantage that can increase the wireless charging efficiency in the wireless charging receiver (110).

Features, structures, effects, and the like described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, features, structures, effects, and the like exemplified in each embodiment may be combined or modified for other embodiments by a person having ordinary knowledge in the field to which the embodiments belong. Therefore, it should be interpreted that contents related to such combinations and modifications are included in the scope of the present invention.

In addition, although the embodiments have been mainly described above, this is merely an example and does not limit the present invention, and those skilled in the art to which the present invention pertains are exemplified above in a range that does not depart from the essential characteristics of the present embodiment. It will be appreciated that various modifications and applications are possible. For example, each component specifically shown in the embodiment can be implemented by modification. And differences related to these modifications and applications should be construed as being included in the scope of the invention defined in the appended claims.

152: power supply
154: converter
156: dc measuring unit
158: inverter
160: transmit antenna
162: antenna current measuring unit
164: impedance matching unit
166: In-band communication unit
168: out-band communication unit
170: control unit

Claims (8)

A converter that converts the input power to a set dc power;
A dc measuring unit measuring current and voltage of the dc power supply;
An inverter that converts the dc power into ac power for wireless charging and supplies it to a transmission antenna;
An antenna current measuring unit measuring an antenna current applied to the transmitting antenna;
An impedance matching unit configured to vary the impedance of the transmitting antenna and set the resonant frequency of the ac power to a set wireless charging frequency; And
If it is determined that at least one change of the dc power source and the ac power source has occurred based on the current and voltage of the dc power source and the antenna current, a control unit controlling at least one of the inverter and the impedance matching unit Containing,
Wireless charging device. According to claim 1,
The converter,
It is a dc-dc converter that outputs the dc power by boosting or reducing the input power,
Wireless charging device. According to claim 1,
The dc measurement unit,
Measuring the current and voltage of the dc power input to the inverter,
Wireless charging device. According to claim 1,
The antenna current measuring unit,
Measuring the antenna current for the AC power source matched by the impedance matching unit,
Wireless charging device. According to claim 1,
The control unit,
When it is determined that the current and voltage of the dc power supply have changed, the operation of the inverter is controlled to control the impedance matching unit such that the resonance frequency of the ac power supply and the ac power supply is varied.
Wireless charging device. According to claim 1,
The control unit,
If it is determined that a change in the antenna current has occurred, the impedance matching unit is controlled so that the resonance frequency of the ac power is variable.
Wireless charging device. According to claim 1,
In the case of wireless charging, an in-band communication unit communicating with the wireless charging frequency; And
When the wireless charging, further comprising an out-band communication unit for communicating at a frequency other than the wireless charging frequency,
Wireless charging device. A converter converting the input power to a set dc power;
a dc measuring unit measuring current and voltage of the dc power supply;
An inverter converting the dc power into ac power for wireless charging and supplying it to a transmitting antenna;
An antenna current measuring unit measuring an antenna current applied to the transmitting antenna;
An impedance matching unit varying the impedance of the transmitting antenna and transmitting the resonant frequency of the ac power to a set wireless charging frequency;
Determining that at least one change among the dc power supply and the ac power supply has occurred based on the current and voltage of the dc power supply and the antenna current; And
And when the controller determines that at least one of the dc power supply and the dc power supply has changed, controlling an operation of at least one of the inverter and the impedance matching unit to vary the resonance frequency of the ac power supply.
How the wireless charging device works.

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