KR102315924B1 - Apparatus and method for wirless power transfer - Google Patents

Abstract

A device for wirelessly transmitting power to an external device is provided.
A wireless power transmission device according to an embodiment includes an adaptive circuit including at least one variable capacitor and a first inductor inductively coupled to an external device, a resonant circuit configured to transmit power to an external device using inductive coupling, and a first DC power supply configured to apply a DC voltage to the adaptive circuit based on a control signal; The capacitance of the variable capacitor is adjusted based on the DC voltage applied to the adaptive circuit.

Description

Apparatus and method for wireless power transfer {APPARATUS AND METHOD FOR WIRLESS POWER TRANSFER}

The present disclosure relates to an apparatus and method for wirelessly transmitting power through inductive coupling.

Various techniques using inductive wireless power transmission have been proposed to wirelessly transmit power.

In the inductive wireless power transmission system, in order to increase the transmission efficiency of power, to control the amount of transmission power or to prevent the negative influence that may have on peripheral devices and the power transmission system due to the electromagnetic properties of the wireless power transmission technology, wireless power Skills to control the transmission system are required.

Conventionally, a technique for controlling an inductive wireless power transmission system using a switching circuit or a controllable DC-DC converter has been proposed, but there are problems in that the efficiency of the entire system decreases and the system cost increases.

The present disclosure relates to an apparatus and method for wirelessly transmitting power through inductive coupling according to various embodiments of the present disclosure, and more particularly, to a wireless power transmitting apparatus and method for adjusting transmission power.

A wireless power transmission device for wirelessly transmitting power to an external device according to an embodiment includes an adaptive circuit including at least one variable capacitor and a product inductively coupled to an external device. A resonant circuit including one inductor, configured to transmit power to an external device using inductive coupling, and a first DC power supply configured to apply a DC voltage to the adaptive circuit based on a control signal A device comprising: a capacitance of the at least one variable capacitor can be adjusted based on a direct current voltage applied to the adaptive circuit.

The wireless power transmission device according to an embodiment may further include a control circuit configured to generate a control signal and apply the generated control signal to the first DC power supply.

According to an embodiment, the wireless power transmission device may further include a first current sensor for measuring a current flowing in the first inductor. Further, the control circuit may be configured to receive information regarding the measured current flowing in the first inductor, and to generate a control signal based on the received information.

According to an embodiment, the control circuit may include a signal receiver.

According to an embodiment, the first inductor may be inductively coupled to a second inductor of an external device, and the control circuit may be configured to receive data regarding a current flowing in the second inductor through a signal receiver.

According to an embodiment, the control circuit may be configured to receive data regarding a current flowing in a load of an external device through a signal receiver and generate a control signal based on the received data.

According to an embodiment, the wireless power transmission device may further include a driving circuit configured to receive DC power output from the second DC power supply and supply AC power to the resonance circuit. Further, the driving circuit may be configured to convert the received DC power into AC power.

According to an embodiment, the wireless power transmission device may further include at least one of a voltage sensor measuring an output voltage of the second DC power supply and a second current sensor measuring an output current. Further, the control circuit may be configured to receive at least one of information about an output voltage and information about an output current measured through the signal receiver, and generate a control signal based on the received at least one information. .

At least one variable capacitor according to an embodiment may be connected in series or in parallel with the first inductor.

The at least one variable capacitor according to an embodiment may be one of a ferroelectric capacitor and a liquid crystal capacitor.

A wireless power transmission device including an adaptive circuit including at least one variable capacitor and a resonant circuit including a first inductor, and a first DC power supply according to an embodiment wirelessly transmits power to an external device The wireless power transmission method includes the steps of applying a control signal to a first DC power supply device, applying a DC voltage output from the first DC power supply device to an adaptive circuit based on the control signal, based on the DC voltage , adjusting a capacitance of the at least one variable capacitor, and transmitting wireless power through the first inductor based on the adjusted capacitance.

The step of applying the control signal to the first DC power supply device according to an embodiment may include measuring a current flowing in the first inductor, and generating a control signal based on information about the measured current flowing in the first inductor may include the step of

The applying of the control signal to the first DC power supply according to an embodiment may include receiving data regarding a current flowing in a second inductor of an external device inductively coupled to the first inductor, and based on the received data to generate a control signal.

The step of applying the control signal to the first DC power supply apparatus according to an embodiment includes receiving data regarding a current flowing in a load of an external device, and generating a control signal based on the received data. can do.

The wireless power transmission device according to an embodiment further includes a driving circuit configured to receive the DC power output from the second DC power supply device and the second DC power supply device, and supply AC power to the resonance circuit, and wireless power The step of applying the control signal to the first DC power supply may include measuring at least one of an output voltage and a current of the second DC power supply, and at least one of information about the measured output voltage and information about the output current. It may include generating a control signal based on one piece of information.

At least one variable capacitor according to an embodiment may be connected in series or in parallel with the first inductor.

The at least one variable capacitor according to an embodiment may be one of a ferroelectric capacitor and a liquid crystal capacitor.

In a computer program product including a computer-readable storage medium according to an embodiment, the storage medium includes an adaptive circuit including at least one variable capacitor, a resonance circuit including a first inductor, and a first direct current Computer program instructions for performing a power transmission method performed by a wireless power transmission device including a power supply and wirelessly transmitting power to an external device, the power transmission method comprising: supplying a control signal to a first DC power supply applying to the device, applying a DC voltage output from the first DC power supply to the adaptive circuit based on the control signal, adjusting the capacitance of the at least one variable capacitor based on the DC voltage, and based on the adjusted capacitance, transmitting wireless power through the first inductor.

The present disclosure relates to an apparatus and method for wirelessly transmitting power through inductive coupling according to various embodiments of the present disclosure, and a wireless power transmission apparatus and method for adjusting transmission power without significantly increasing system cost while increasing overall system efficiency this is provided

1 is a diagram schematically illustrating a wireless power transmission system according to an embodiment.
2 is a diagram illustrating a block diagram of a wireless power transmission device according to an embodiment.
3 is a diagram illustrating a block diagram of a wireless power transmission device according to an embodiment.
4 is a diagram illustrating a wireless power transmission system according to an embodiment.
5 is a diagram illustrating a flowchart of a method for transmitting power wirelessly according to an embodiment.
6 is a diagram illustrating a method for wirelessly transmitting power by a wireless power transmitting device according to an embodiment.
7 is a diagram illustrating an implementation example of a wireless power transmission system according to an embodiment.

In general, a wireless power supply system uses an inductive wireless power transfer (WPT) scheme to wirelessly transmit power. In addition, the inductive wireless power transmission system is an inductive power supply (transmitter) using a primary coil to wirelessly transmit power in the form of various electromagnetic fields and a remote device using a secondary coil to convert electromagnetic field energy into electric power ( receiver) may be included.

In the inductive wireless power transmission system, the adaptive wireless power transmission control improves power transmission efficiency, controls the amount of transmission power, and due to the electromagnetic properties of the wireless power transmission technology, peripheral devices and power transmission systems It has the advantage of being able to adjust operating parameters over time in order to prevent operation in a specific mode that may have a negative effect on the .

In general, an inductive wireless power transmission system may include a transmitter and a receiver. For example, the transmission unit may include at least one transmission inductor and a driving current circuit for allowing current to flow in the transmission inductor. In addition, the receiving unit may include at least one receiving inductor and a rectifying circuit.

The transmitter may be connected to a direct current (DC) or alternating current (AC) power source, for example a voltage source and/or a current source. In general, changes in the coupling between the transmitter and receiver, load pick-up current or In order to adjust the amount of power transmitted while different operating conditions change, a control function needs to be implemented in the wireless power transfer system.

For example, in a charger having a charging area of a size larger than the maximum size of the device to be charged, as well as a device having various power consumption and/or a wireless charger designed to simultaneously charge a plurality of devices, the control function described above is implemented need to be

Using several approaches, control functions can be implemented in a wireless power transfer system. For example, a method using a controllable DC-DC converter in a transmitter and a receiver, implementing an adjustment function in a circuit that drives a current in an inductor for transmission, and applying an adaptive matching technique There is this. In order to increase the control function, several approaches can be used simultaneously.

As an example of an approach for implementing a control function in a wireless power transmission system, an approach for adjusting a current in a transmission inductor is to couple the transmission inductor to a driving circuit in a resonant circuit. and changing the switching frequency of the driving circuit. For example, a resonant circuit may be implemented as a series or parallel resonant circuit or a more complex combination of an inductor and a capacitor. Also, in order to adjust the current in the transmission inductor, frequency dependence, which is a characteristic of a resonant circuit, may be used.

The approach is described in Wireless Power Consortium (QI Compatibility Specification), System Technology Wireless Power Transmission, Volume 1, Low Power, Part 1: Interface Definition 1.0.2. Version, according to the specification of June 2013 (hereafter Specification [1]), used in several power transmitter designs, and patent literature (US 2013/0082536, Taylor JB, Moor CJ, Baarman DW, Mollema SA, Moes BC, Kuyvenhoven) NW, Control Enhancement System and Method in a Wireless Power Supply System, announced on April 4, 2013) (hereinafter, [2]).

This approach may have a problem in that the frequency of the current flowing in the transmission inductor changes as the switching frequency in the driving circuit changes.

In general, in a wireless power transmission system, in order to eliminate a phase shift between the induced current and the induced voltage in the receiving inductor, the inductance of the receiving inductor is compensated by a capacitor or a matching circuit. can be In order to obtain maximum power transfer efficiency, or maximum power transfer performance factor, it may be necessary to eliminate the phase difference between the induced current and the induced voltage flowing in the receiving inductor.

For example, the inductance of the receiving inductor may be compensated by a single capacitor or matching circuit at a specific frequency. For example, when the operating frequency is changed, the power transmission efficiency may change due to a change in impedance in the circuit, which may cause a phase difference between the induced current and the induced voltage flowing in the receiving inductor.

In addition, according to the requirements of the wireless power transmission standard developed by the AirFuel Alliance working group, which is the predecessor of the wireless power alliance, the band of the operating frequency allocated to the current flowing in the transmission inductor is relatively Due to the narrow and narrow operating frequency band range, it may be difficult to apply this approach. Therefore, under the wireless power transmission system according to the above standard, a constant switching frequency must be used in the driving circuit.

Another example of an approach for regulating the current in an inductor for transmission is to use a controllable DC-DC converter to vary the input DC voltage.

This approach is also used in the design of various power transmitters conforming to the standard [1], and is disclosed in the patent document [2]. The disadvantage of this approach stems from the need for a separate DC-DC converter with a controllable output voltage prior to the driving circuit of the current flowing in the transmission inductor. The DC-DC converter reduces the efficiency of the overall system and increases the system cost. In addition, only the adjustment function according to the corresponding approach cannot guarantee stable operation of the wireless power transmission system under all possible operating conditions.

European Patent Publication (WO 2016/01362, NN Olyunin, AG Chernokalov, "Method for control in wireless power transfer systems") discloses a method between complementarily turned-on switches in a bridge-type circuit. Another approach is disclosed for controlling the current in an inductor for transmission by varying the difference in duty cycle. This approach has the disadvantage of being complicated to implement at operating frequencies above 1 MHz. This complexity is related to the increasing complexity of driving circuits with variable duty cycles as frequency increases.

According to an embodiment, in order to adjust the current in the transmission inductor, frequency dependence, which is a characteristic of a resonance circuit, may be used. For example, the operating frequency of the driving circuit of the transmission unit may be kept constant. Instead of changing the operating frequency, the characteristics of the resonant circuit, for example impedance, may be changed. By changing the capacitance of one or more voltage controlled variable capacitors that are part of the resonant circuit, the impedance of the resonant circuit can be changed.

To change the capacitance of the variable capacitor, an additional DC power supply with a controllable variable output voltage may be required. However, the added DC power supply does not transmit power, so it does not significantly increase the system cost.

Accordingly, power transfer efficiency can be improved in a wireless power transfer system designed to simultaneously charge a plurality of devices without increasing complexity and size.

One embodiment allows for more flexible positioning of the device being charged in relation to the charger, increases the charging area, reduces the power consumption of the wireless power transfer system, and allows for variations in charging rate and input voltage may increase the error. In addition, by reducing power loss and heating of both the device being charged and the charger, reliability, safety, and life can be extended.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art to which the present disclosure pertains can easily implement them. However, the present disclosure may be implemented in several different forms and is not limited to the embodiments described herein. And in order to clearly explain the present disclosure in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Hereinafter, the present disclosure will be described in detail with reference to the accompanying drawings.

1 is a diagram schematically illustrating a wireless power transmission system according to an embodiment.

The wireless power transmission system may include a wireless power transmission device 100 and a wireless power reception device 120 .

The wireless power transmitting device 100 according to an embodiment may inductively transmit power to the wireless power receiving device 120 . For example, the transmission inductor included in the wireless power transmission device 100 may be inductively coupled to the reception inductor included in the wireless power reception device 120 . Also, the wireless power transmitting device 100 may transmit power to the wireless power receiving device 120 using inductive coupling.

The wireless power transmission device 100 may include a first DC power supply, a variable capacitor, and an inductor for transmission.

The wireless power transmitting device 100 may adjust power transmitted to the wireless power receiving device 120 . For example, the wireless power transmitting device 100 may adjust the power transmitted to the wireless power receiving device 120 by adjusting the amplitude of the current flowing in the inductor for transmission.

For example, the wireless power transmission device 100 may adjust the DC voltage applied from the first DC power supply to the variable capacitor. Also, the capacitance of the variable capacitor may be adjusted based on the DC voltage supplied from the first DC power supply. In addition, as the capacitance of the variable capacitor is adjusted, the current flowing in the transmission inductor may be adjusted. In addition, as the current flowing in the transmission inductor is adjusted, the power transmitted to the wireless power receiving device 120 may be adjusted.

2 is a diagram illustrating a block diagram of a wireless power transmission device 100 according to an embodiment.

Referring to FIG. 2 , the wireless power transmission device 100 may include a first DC power supply 210 and at least one variable capacitor 220 .

The first DC power supply 210 according to an embodiment may be configured to apply a DC voltage to the at least one variable capacitor 220 based on a control signal.

The first DC power supply 210 according to an embodiment may be a controllable DC voltage source. For example, the first DC power supply 210 may be a current controlled DC voltage source, and the control signal may be a current signal. As another example, the first DC power supply 210 may be a voltage controlled DC voltage source, and the control signal may be a voltage signal.

The first DC power supply 210 according to an embodiment may be configured to receive a control signal. Also, the first DC power supply 210 may be configured to adjust the output DC voltage based on the control signal.

The first DC power supply 210 according to an embodiment may be configured to apply the output DC voltage to the at least one variable capacitor 220 .

At least one variable capacitor 220 according to an embodiment may be a voltage variable capacitor. The capacitance of the at least one variable capacitor 220 according to an embodiment may be adjusted based on a DC voltage supplied from the first DC power supply device 210 .

As the capacitance of the at least one variable capacitor 220 according to an embodiment is adjusted, the impedance of the resonance circuit including the at least one variable capacitor and the transmission inductor may be adjusted. Also, as the impedance of the resonance circuit is adjusted, the current flowing in the transmission inductor may be adjusted. As the current flowing in the inductor for transmission according to an embodiment is adjusted, the power transmitted to the wireless power receiving device 120 may be adjusted.

In general, a series of fixed capacitors may be used as capacitors in an adaptive circuit to obtain a suitable capacitance in a resonant circuit. A series of fixed capacitors may be connected to a switching circuit assigned to each of the fixed capacitors. The switching circuit may determine whether a fixed capacitor coupled to the switching circuit affects the impedance of the resonant circuit based on a state of the switching circuit, eg, an open or short state. However, circuits using fixed capacitors can be relatively large and complex, and can be inaccurate because the contribution of each capacitor to impedance is discontinuous. In addition, since the withstand voltage and withstand current of the switching element are relatively large, the complexity and cost of the switching element may be increased.

In order to solve the problem of using a series of fixed capacitors and switching circuits, it is preferable to use a DC voltage control variable capacitor. As the adjustment range of each of the variable capacitors is wide, the number, size, complexity, and loss of capacitors used in the adaptive circuit may be reduced, and reliability may be increased.

When a variable capacitor is used, a DC voltage supply having a controllable and variable output voltage is required, but since the DC voltage supply has low power, no loss, and is small compared to the above-mentioned gate circuit arrangement, the system It does not substantially affect the overall complexity and characteristics. Further, even if the number of variable capacitors in the adaptive circuit increases from one to two or more, a DC voltage supply for each capacitor is not required. That is, even if the adjustment range of the capacitance is further increased, the complexity and cost of the system are not excessively increased.

At least one variable capacitor 220 according to an embodiment may include a nonlinear dielectric material. As the DC voltage applied to the at least one variable capacitor 220 according to an embodiment is adjusted, the magnetic permeability of the dielectric constituting the at least one variable capacitor 220 may change. A ratio of the maximum capacitance to the minimum capacitance of the at least one variable capacitor 220 according to an embodiment may be 1.4 or more. For example, the at least one variable capacitor 220 may include, but is not limited to, a ferroelectric capacitor, a liquid crystal capacitor, or the like.

Various embodiments of the present disclosure provide variable coupling between a variable load, a variable input voltage, or a power transmitter, for example, the wireless power transmitting device 100 and a power receiver, for example, the wireless power receiving device 120 . It can be applied to a wireless power transmission system with

In particular, various embodiments of the present disclosure provide a wireless charger capable of charging a mobile device having different power consumption, such as a wearable device, a smart phone, and a tablet computer, and a device to be charged It can be applied to a wireless charger that has a charging area of a size larger than the maximum size of the wireless charger and allows charging devices to be relatively freely placed and a wireless charger capable of charging a plurality of devices at the same time.

3 is a diagram illustrating a block diagram of a wireless power transmission device 100 according to an embodiment.

Referring to FIG. 3 , the wireless power transmission device 100 may include a first DC power supply 210 and a resonance circuit 310 . Also, the resonance circuit 310 may include an adaptive circuit 320 including at least one variable capacitor 220 and at least one transmission inductor 330 .

The first DC power supply 210 and the resonance circuit 310 according to an embodiment may be electrically connected. For example, the resonance circuit 310 may be connected to an output terminal of the first DC power supply 210 .

The first DC power supply 210 according to an embodiment may be configured to apply a DC voltage to the adaptive circuit 320 based on the control signal 340 .

The first DC voltage supply device 200 according to an embodiment may be configured to receive the control signal 340 . For example, the first DC power supply 210 may be configured to receive the control signal 340 from other components of the wireless power transmission device 100 . In order to adjust the output voltage of the first DC power supply device 210 , the control signal 340 according to an embodiment includes information about the current and/or voltage in the wireless power transmission device 100 and the wireless power receiving device. may be determined based on at least one of data relating to current and/or voltage in 120 .

The first DC power supply 210 according to an embodiment may be configured to adjust the output DC voltage based on the control signal 340 . For example, the first DC power supply 210 may be configured to increase or decrease the output DC voltage based on the control signal 340 .

The first DC power supply 210 according to an embodiment may be configured to apply an output DC voltage to the adaptive circuit 320 . For example, the first DC power supply 210 may be configured to apply the output DC voltage to the variable capacitor 220 included in the at least one adaptive circuit 320 .

The first DC power supply 210 according to an embodiment may be configured to apply a DC voltage for adjusting the capacitance of at least one variable capacitor to the adaptive circuit. For example, the first DC power supply 210 converts a DC voltage for adjusting the impedance of the resonance circuit 310 including the at least one variable capacitor by adjusting the capacitance of the at least one variable capacitor to the adaptive circuit ( 320) may be configured to authorize.

As described above, the resonance circuit 310 according to an embodiment may include an adaptive circuit 320 and at least one transmission inductor 330 . Also, the adaptive circuit 320 may include at least one variable capacitor 220 .

The adaptive circuit 320 according to an embodiment may include one or more variable capacitors 220 . In addition, the adaptive circuit 320 may include a fixed reactive element such as an inductor, a fixed capacitor, and a transformer.

The adaptive circuit 320 according to an embodiment may include a plurality of variable capacitors 220 . For example, the plurality of variable capacitors 220 may be connected in series or parallel to each other.

At least one variable capacitor 220 according to an embodiment may be connected in series or in parallel with the transmission inductor 330 .

The impedance of the resonance circuit 310 according to an embodiment may be determined based on the impedance of the adaptive circuit 320 and the impedance of the at least one transmission inductor 330 . For example, the impedance of the resonance circuit 310 may be determined based on the impedance of the at least one variable capacitor 220 included in the adaptive circuit 320 and the impedance of the at least one transmission inductor 330 .

The adaptive circuit 320 according to an embodiment may be configured to adjust the capacitance of the at least one variable capacitor 220 based on the DC voltage applied to the adaptive circuit 320 .

The capacitance of the at least one variable capacitor 220 according to an embodiment may be adjusted based on a DC voltage supplied to the at least one variable capacitor 220 . For example, the capacitance of the at least one variable capacitor 220 may be adjusted based on the DC voltage supplied from the first DC power supply 210 .

For example, as the DC voltage supplied to the at least one variable capacitor 220 increases, the capacitance of the at least one variable capacitor 220 may increase. As another example, as the DC voltage supplied to the at least one variable capacitor 220 decreases, the capacitance of the at least one variable capacitor 220 may increase.

At least one transmission inductor 330 according to an embodiment may be configured to transmit power to the wireless power receiving device 120 through inductive coupling with the wireless power receiving device 120 .

For example, the at least one inductor for transmission 330 may be inductively coupled to the inductor for reception of the wireless power receiving device 120 . In addition, the at least one inductor for transmission 330 may be inductively coupled to a plurality of inductors for reception of a plurality of wireless power receiving devices.

For example, the at least one transmission inductor 330 may transmit power to the wireless power receiving device 120 through inductive coupling. For example, as an AC current flows in the transmission inductor 330 , power may be transmitted in the form of electromagnetic energy to the reception inductor of the wireless power receiving device 120 . For example, the transmitted electromagnetic energy may be converted into electrical energy in a receiving inductor. For example, as the transmitted electromagnetic energy is converted into electrical energy in the receiving inductor, an alternating current may flow in the receiving inductor.

Also, as the amplitude of the alternating current flowing in the at least one transmission inductor 330 is adjusted, the power transmitted to the wireless power receiving device 120 may be adjusted.

4 is a diagram illustrating a wireless power transmission system according to an embodiment.

Referring to FIG. 4 , a wireless power transmission system according to an embodiment may include a wireless power transmission device 100 and a wireless power reception device 120 .

The wireless power transmission device 100 may be, for example, a charger. The wireless powered device 120 may be, for example, a charged device.

Although only one wireless power receiving device 120 is illustrated in FIG. 4 , the wireless power transmission system according to an embodiment may include a plurality of wireless power receiving devices.

Hereinafter, in the description of FIG. 4 , content overlapping with the description of FIG. 3 will be omitted.

The wireless power transmission device 100 according to an embodiment includes a second DC power supply 410 , a driving circuit 420 , a control circuit 430 , a first DC power supply 210 , and a resonance circuit 310 . ) may be included. Also, the resonance circuit 310 according to an embodiment may include an adaptive circuit 320 including at least one variable capacitor 220 and an inductor 330 for transmission.

In addition, the wireless power receiving device 120 according to an embodiment may include a receiving inductor 460 and a load 470 .

The second DC power supply 410 according to an embodiment may be configured to apply DC power to the driving circuit 420 . The second DC power supply 410 according to an embodiment may be configured to apply an output DC voltage or an output DC current to the driving circuit 420 .

The driving circuit 420 according to an embodiment may be configured to apply AC power to the resonance circuit 310 based on the DC power supplied from the second DC power supply device 410 .

For example, the driving circuit 420 may be configured to apply an AC voltage or an AC current to the resonance circuit 310 . In addition, the driving circuit 420 may apply AC power to the resonance circuit 310 so that an AC current flows in the transmission inductor 330 . For example, the driving circuit 420 may be configured to apply an AC voltage or AC current having a predetermined driving frequency to the resonance circuit 310 .

The driving circuit 420 according to an embodiment may be configured to convert DC power received from the second DC power supply 410 into AC power. For example, the driving circuit 420 may be configured to convert a DC voltage or a DC current received from the second DC power supply device 410 into an AC voltage or an AC current.

The driving circuit 420 according to an embodiment may be configured to apply the converted AC power to the resonance circuit 310 . For example, the driving circuit 420 may be configured to apply the converted AC voltage or AC current to the resonance circuit 310 .

The control circuit 430 according to an embodiment may be configured to generate a control signal 340 and apply the generated control signal 340 to the first DC power supply device 210 .

The wireless power transmission device 100 according to an embodiment may further include a current sensor (not shown) for measuring a current flowing in the transmission inductor 330 . The control circuit 430 may be configured to receive information about a current flowing in the transmission inductor 330 from a current sensor of the transmission inductor 330 . For example, the control circuit 430 may be configured to receive information related to the amplitude of the current flowing in the transmission inductor 330 from a current sensor of the transmission inductor 330 .

The wireless power transmission device 100 according to an embodiment may further include a voltage sensor (not shown) for measuring the voltage of the transmission inductor 330 . For example, the control circuit 430 may be configured to receive information regarding the induced voltage of the transmission inductor 330 .

The wireless power transmission device 100 according to an embodiment may further include a power sensor (not shown) for measuring power consumed by the transmission inductor 330 . The control circuit 430 may be configured to receive information regarding the power consumed by the measured transmission inductor 330 .

The wireless power transmission device 100 according to an embodiment may include a voltage sensor (not shown) for measuring an output voltage of the second DC power supply 410 . For example, the wireless power transmission device 100 may include a voltage sensor for measuring an output voltage applied to the driving circuit 420 from the second DC power supply 410 . For example, the control circuit 430 may be configured to receive information regarding the measured output voltage.

The wireless power transmission device 100 according to an embodiment may include a current sensor (not shown) for measuring the output current of the second DC power supply 410 . For example, the wireless power transmission device 100 may include a current sensor for measuring an output current applied from the second DC power supply 410 to the driving circuit 420 . The control circuit 430 may be configured to receive information regarding the measured output current.

The wireless power transmission device 100 according to an embodiment may include a power sensor (not shown) that measures the output power of the second DC power supply 410 . For example, the wireless power transmission device 100 may include a power sensor that measures output power applied from the second DC power supply 410 to the driving circuit 420 . The control circuit 430 may be configured to receive information regarding the measured output power.

The control circuit 430 according to an embodiment includes a signal receiver (not shown), and transmits the control signal 340 generated based on data received by the wireless power receiving device 120 through the signal receiver to the first DC power. It may be configured to apply to the supply device 210 .

The wireless power receiving device 120 according to an embodiment may further include a current sensor (not shown) for measuring a current flowing through the receiving inductor 460 or the load 470 . The control circuit 430 may be configured to receive data regarding the current flowing in the reception inductor 460 or the load 470 through the signal receiver.

The wireless power receiving device 120 according to an embodiment may further include a voltage sensor (not shown) for measuring the voltage of the receiving inductor 460 or the load 470 . The control circuit 430 may be configured to receive data regarding the voltage of the receiving inductor 460 or the load 470 through the signal receiver.

The wireless power receiving device 120 according to an embodiment may further include a power sensor (not shown) for measuring power consumed by the receiving inductor 460 or the load 470 . The control circuit 430 may be configured to receive data regarding power consumed by the receiving inductor 460 or the load 470 through the signal receiver.

The control circuit 430 according to an embodiment may include a desired current, a desired voltage, and/or a receiving inductor 460 or a load 470 included in the wireless power receiving device 120 . A request to change the current flowing in the inductor for transmission including data on desired power consumption may be received through the signal receiver.

The control circuit 430 according to an embodiment of the present invention provides data from the wireless power receiving device 120 through a signal receiver, for example, using Bluetooth, ZigBee, modulation of a load, or another method according to a standard. can receive

The control circuit 430 according to an embodiment may be configured to generate a control signal 340 based on received information and/or data. For example, the control circuit 430 may generate the control signal 340 for adjusting the output DC voltage of the first DC power supply 210 based on information and/or data received through the signal receiver. have. For example, the control circuit 430 may determine an appropriate output DC voltage of the first DC power supply 210 . The appropriate output DC voltage according to an embodiment may provide an appropriate capacitance of the capacitor to obtain a predetermined operating frequency of the resonance circuit. Also, the control circuit 430 may generate the control signal 340 based on the determined appropriate output DC voltage.

The control circuit 430 according to an embodiment may be configured to apply the generated control signal 340 to the first DC power supply 210 . For example, the control circuit 430 applies the control signal 340 to the first DC power supply 210 based on the received information and/or data and a control algorithm implemented in the control circuit 430 . can do.

5 is a diagram illustrating a flowchart of a method for wirelessly transmitting power by the wireless power transmitting device 100 according to an embodiment.

The method shown in FIG. 5 may be performed by each configuration of the wireless power transmission device 100 shown in FIG. 3 or FIG. 4 .

The wireless power transmission device 100 according to an embodiment may include an adaptive circuit including at least one variable capacitor and a first DC voltage supply device.

In operation 510 , the wireless power transmission device 100 according to an embodiment may apply a control signal to the first DC power supply included in the wireless power transmission device 100 .

The wireless power transmission device 100 according to an embodiment may generate a control signal for adjusting the output DC voltage of the first DC power supply included in the wireless power transmission device 100 .

The wireless power transmission device 100 according to an embodiment may include a control circuit including a signal receiver. The control circuit 100 according to an embodiment may receive information and/or data through a signal receiver. The control circuit 100 according to an embodiment may generate a control signal based on the received information and/or data.

The wireless power transmission device 100 according to an embodiment may apply the generated control signal to the first DC power supply of the wireless power transmission device 100 . The control circuit 100 according to an embodiment may apply a control signal to the first DC power supply included in the wireless power transmission device 100 . The control circuit 100 according to an embodiment may apply the control signal in the form of a voltage signal or a current signal to the first DC power supply included in the wireless power transmission device 100 .

In step 520 , the wireless power transmission device 100 according to an embodiment applies the DC voltage output from the first DC power supply device to the adaptive circuit included in the wireless power transmission device 100 based on the control signal. can

The wireless power transmission device 100 according to an embodiment may apply a control signal to the first DC voltage supply device included in the wireless power transmission device 100 to adjust the output DC voltage of the first DC power supply device. . Also, the wireless power transmission device 100 may apply the DC voltage output from the first DC power supply device to the adaptive circuit included in the wireless power transmission device 100 . For example, the wireless power transmission device 100 may apply the DC voltage output from the first DC power supply to at least one variable capacitor included in the adaptive circuit.

In operation 530, the wireless power transmission device 100 according to an embodiment may adjust the capacitance of at least one variable capacitor based on the DC voltage.

The wireless power transmission device 100 according to an embodiment may adjust the capacitance of the at least one variable capacitor based on the DC voltage output from the first DC power supply. For example, the wireless power transmission device 100 may adjust the impedance of the resonance circuit including the at least one variable capacitor by adjusting the capacitance of the at least one variable capacitor. In addition, the wireless power transmission device 100 may adjust the amplitude of the current flowing in the transmission inductor included in the resonance circuit by adjusting the impedance of the resonance circuit.

6 is a diagram illustrating a method for wirelessly transmitting power by the wireless power transmitting device 100 according to an embodiment.

The wireless power transmission device 100 according to an embodiment may include an adaptive circuit including at least one variable capacitor, a resonance circuit including an inductor for transmission, and a first DC voltage supply device. In addition, the wireless power transmission device 100 may include a control circuit configured to apply the control signal generated based on the received information and/or data to the first DC power supply. Also, the wireless power transmission device 100 may include a driving circuit configured to apply AC power to the resonance circuit based on the DC power received from the second DC power supply.

In step 610 , the wireless power transmission device 100 receives information and/or data from at least one of the current sensor of the inductor for transmission, the voltage and/or current sensor of the second DC power supply, and the wireless power receiving device 120 . can receive For example, the received data may include information and/or data regarding measured currents and/or voltages.

The wireless power transmission device 100 according to an embodiment may include a current sensor for measuring a current flowing in an inductor for transmission. For example, the wireless power transmission device 100 may measure a current flowing in an inductor for transmission using a current sensor. In addition, the control circuit may receive information regarding the current flowing in the transmission inductor. For example, the control circuit may receive information about the current flowing in the transmission inductor from a current sensor of the transmission inductor.

The wireless power transmission device 100 according to an embodiment may include a voltage sensor and/or a current sensor for measuring an output voltage and/or an output current of the second DC power supply.

The wireless power transmission device 100 according to an embodiment may measure an output voltage and/or an output current of the second DC power supply using a voltage sensor and/or a current sensor. The control circuit according to an embodiment may receive information about an output voltage and/or an output current of the second DC power supply. For example, the control circuit may receive information about the output voltage and/or output current of the second DC power supply from a voltage sensor and/or current sensor of the second DC power supply.

The control circuit according to an embodiment may receive data regarding the current flowing in the receiving inductor or the load included in the wireless power receiving device 120 through the signal receiver. The control circuit according to an embodiment may receive data regarding an appropriate current of a receiving inductor or a load included in the wireless power receiving device 120 .

In operation 620, the wireless power transmission device 100 according to an embodiment may determine whether a change in the current flowing in the inductor for transmission is required based on the information and/or data received in operation 610. For example, the control circuit included in the wireless power transmission device 100 may determine whether a change in current flowing in the inductor for transmission is required.

The wireless power transmission device 100 according to an embodiment may determine whether a change in the current flowing in the transmission inductor is required according to information about the current flowing in the transmission inductor.

The wireless power transmission device 100 according to an embodiment may determine whether it is necessary to change the current flowing in the transmission inductor according to information about the output voltage and/or output current of the second DC power supply device.

The wireless power transmission device 100 according to an embodiment may determine whether a change in the current flowing in the transmission inductor is required according to data regarding the current flowing in the receiving inductor or the load included in the wireless power receiving device. According to an embodiment, the wireless power transmission device 100 may determine whether it is necessary to change the current flowing in the transmission inductor based on data regarding the appropriate current of the reception inductor or load included in the wireless power reception device. .

In step 620 , the wireless power transmission device 100 according to an embodiment determines that a change in current flowing in the inductor for transmission is not required, and returns to step 610 to repeat the process. Also, in step 620, the wireless power transmission device 100 according to an embodiment may perform step 630 when it is determined that a change in current flowing in the inductor for transmission is required.

In operation 630 , the wireless power transmission device 100 according to an embodiment may apply a control signal to the first DC power supply included in the wireless power transmission device 100 . For example, the wireless power transmission device 100 may apply a control signal generated by the control circuit to the first DC voltage supply device. For example, the wireless power transmission device 100 may apply a control signal in the form of a voltage signal or a current signal to the first DC voltage supply device.

In operation 640, the wireless power transmission device 100 may adjust the output voltage of the first DC power supply. For example, the wireless power transmission device 100 may adjust the output DC voltage of the first DC power supply device by applying a control signal to the first DC power supply device included in the wireless power transmission device 100 . For example, the wireless power transmission device 100 may adjust the output DC voltage of the first DC power supply by applying a control signal in the form of a voltage signal or a current signal to the first DC power supply.

In operation 650, the wireless power transmission device 100 according to an embodiment may adjust the capacitance of at least one variable capacitor.

The wireless power transmission device 100 according to an embodiment may apply the output DC voltage of the first DC power supply to an adaptive circuit including at least one variable capacitor. For example, the wireless power transmission device 100 may apply the output DC voltage of the first DC power supply to at least one variable capacitor included in the adaptive circuit.

The wireless power transmission device 100 according to an embodiment may adjust the capacitance of the at least one variable capacitor by applying the DC voltage output from the first DC power supply to the adaptive circuit. For example, the wireless power transmission device 100 may adjust the capacitance of the at least one variable capacitor by applying the DC voltage output from the first DC power supply to the at least one variable capacitor.

The wireless power transmission device 100 according to an embodiment may adjust the resonance characteristics of the resonance circuit including the at least one variable capacitor by adjusting the capacitance of the at least one variable capacitor. For example, the wireless power transmission device 100 may adjust the impedance of the resonance circuit including the at least one variable capacitor by adjusting the capacitance of the at least one variable capacitor.

In operation 660, the wireless power transmission device 100 according to an embodiment may adjust the current flowing in the inductor for transmission. For example, the wireless power transmission device 100 may adjust the current flowing in the transmission inductor by adjusting the capacitance of the at least one variable capacitor. For example, the wireless power transmission device 100 may maintain a driving frequency of a driving circuit coupled to the transmission inductor and adjust the amplitude of a current flowing in the transmission inductor.

The wireless power transmission device 100 according to an embodiment may adjust the power transmitted to the wireless power reception device by adjusting the current flowing in the transmission inductor. For example, the wireless power transmitting device 100 may adjust the power transmitted to the wireless power receiving device by adjusting the amplitude of the current flowing in the transmission inductor.

7 is a diagram illustrating an implementation example of a wireless power transmission system according to an embodiment.

Referring to FIG. 7 , a plurality of wirelessly powered devices, for example, a device 722 , a device 724 , and a device 726 are optionally on the charging pad 710 of the wireless powered device 100 . can be placed.

A plurality of wireless power receiving devices disposed on the charging pad 710 according to an embodiment, for example, the device 722 , the device 724 , and the receiving inductor included in each of the device 726 are wireless It may be inductively coupled to an inductor for transmission included in the power transmission device 100 .

The wireless power transmission device 100 according to an embodiment wirelessly transmits power to a plurality of wireless power receiving devices, for example, the device 722 , the device 724 , and the device 726 through inductive coupling. can receive

Although only an example in which a plurality of wireless power receiving devices are disposed on the charging pad 710 is illustrated in FIG. 7 , the wireless power transmitting device 100 provides a plurality of wireless power receiving devices disposed in an area other than the charging pad 710 to the plurality of wireless power receiving devices. Power can be transmitted wirelessly. Also, the wireless power transmitting device 100 may wirelessly transmit power to a plurality of wireless power receiving devices that are physically separated from the wireless power transmitting device 100 .

The wireless power transfer system according to an embodiment is charged in relation to a charger due to the improved power transfer efficiency of the wireless power transfer system designed to charge multiple devices, for example, multiple devices at the same time without increasing complexity and size. Allows for more flexible arrangement of devices.

Although various embodiments of the present disclosure have been described in detail with reference to the accompanying drawings, these are illustrative and not intended to limit the present invention, and the present invention is not to be construed as being limited to specific embodiments. In addition, it will be apparent to those skilled in the art based on the information contained in the detailed description and common knowledge in the art that the specific layout and design of the present disclosure, and various modifications of the embodiments, are encompassed by the rights herein.

Although not specifically stated, it should be understood that storing data, programs, control algorithms, etc. implies the presence of machine-readable media. For example, machine-readable media include read only memory (ROM), random access memory (RAM), registers, caches, solid-state storage, and internal hard disks. and magnetic media, such as removable disks, and magneto-optical and optical media, such as CD-ROM and digital versatile disc (DVD), and any other storage media known in the art. can do.

Although this disclosure does not define specific hardware and software for implementing the blocks in the drawings, those skilled in the art will know that the present invention is not limited to implementation by specific hardware or software, and any conventional hardware and/or software may be used as embodiments of the present disclosure. You will be able to understand what is used to implement it. Accordingly, hardware may include one or more application specific integrated circuits, digital signal processors, digital signal processing devices, programmable logic devices, for performing the functions of the present disclosure. devices), field programmable gate arrays, processors, controllers, microcontrollers, microprocessors, electronic devices and other electronic modules, computers, and combinations thereof can be implemented as

The design of the components disclosed herein, unless otherwise stated, is known to those skilled in the art and is not specifically described herein. The components of the device, for example the housing, may be made of any suitable material, such as aluminum, copper, stainless steel, titanium, carbon fiber composite materials, plastic, or the like. These components can be manufactured by known methods, for example machining and lost wax casting. In addition, since operations such as assembly and connection according to the above description are known to those skilled in the art, they will not be described in detail herein.

A functional link of a component should be understood as a link that provides precise interaction between the elements and the realization of a specific function of the component. For example, a functional link may include a function capable of exchanging information, a function of transmitting an electric current, a function of transmitting mechanical motion, a function of transmitting light, sound waves, electromagnetic or mechanical vibration, and the like. Links are defined by the nature of the mutual cooperation of the components and, unless otherwise stated, are provided by conventional means using known principles.

The components/units of the proposed wireless power transmission device 100 are disposed on the same frame/circuit board, are functionally connected through communication links, are structurally connected by a mounting (assembly) operation, and have the same housing (housing). ) can be included. A communication link or channel is a conventional standard communication link, unless otherwise stated, and no creative effort is required to implement it in practice. The communication link may be a wire, a set of wires, a bus, a path, a wireless communication link, for example, a wireless communication link using inductive coupling, radio frequency, infrared, or ultrasound. Protocols for communication over a communication link are known in the art and are not specifically detailed herein.

A function of a component represented by a single component in the description or claims of the present disclosure may be implemented by several components of a device when actually implemented, and conversely, the function of the component represented by several components is the actual implementation. If possible, it can be implemented by a single component.

As used herein, the terms “first,” “second,” and the like may be used to describe various components, parts, regions, hierarchies, and/or sections. These terms are only used to distinguish one element from another, and the elements are not limited to these terms, unless otherwise stated or clearly used in context. Accordingly, without departing from the scope of the present disclosure, a first component, component, region, layer, and/or section may be defined as a second component, component, region, layer, and/or section. As used herein, the term “and/or” includes any and all combinations of each of one or more of the listed items. Elements denoted in the singular do not exclude plural elements unless otherwise specified.

As used herein, a method includes one or more steps or acts for implementing the disclosed method. If a specific order of steps and/or actions is not determined, one or more steps and/or actions may be performed outside the order described in this disclosure. For example, two steps and/or operations described in succession may be executed at substantially the same time, or in reverse order, depending on the functionality involved.

Claims (18)

A device for wirelessly transmitting power to an external device, comprising:
an adaptive circuit including at least one variable capacitor and a first inductor inductively coupled to the external device, using the inductive coupling a resonance circuit configured to transmit power to the external device; and
a first DC power supply configured to apply a DC voltage to the adaptive circuit based on a control signal;
and a capacitance of the at least one variable capacitor is adjusted based on the DC voltage applied to the adaptive circuit. The method of claim 1,
and a control circuit configured to generate the control signal and apply the generated control signal to the first DC power supply. 3. The method of claim 2,
A first current sensor for measuring the current flowing in the first inductor,
and the control circuit is configured to receive information regarding the measured current flowing in the first inductor and generate the control signal based on the received information. 3. The method of claim 2,
The control circuit comprises a signal receiver,
the first inductor is inductively coupled to a second inductor of the external device;
and the control circuit is configured to receive data regarding a current flowing in the second inductor via the signal receiver and generate the control signal based on the received data. 3. The method of claim 2,
The control circuit further comprises a signal receiver,
The control circuit is configured to receive data regarding a current flowing in a load of the external device through the signal receiver, and generate the control signal based on the received data. 3. The method of claim 2,
a second DC power supply; and
and a driving circuit configured to receive the DC power output from the second DC power supply and supply AC power to the resonance circuit. 7. The method of claim 6,
and the driving circuit is configured to convert the received DC power into AC power. 7. The method of claim 6,
At least one of a voltage sensor measuring an output voltage of the second DC power supply and a second current sensor measuring an output current,
The control circuit is configured to receive at least one of information about the measured output voltage and information about an output current, and generate the control signal based on the received at least one information. . The method of claim 1,
The at least one variable capacitor is connected in series or parallel with the first inductor. The method of claim 1,
The at least one variable capacitor is one of a ferroelectric capacitor and a liquid crystal capacitor. A method for a wireless power transmission device including an adaptive circuit including at least one variable capacitor and a resonant circuit including a first inductor, and a first DC power supply to wirelessly transmit power to an external device, the method comprising:
applying a control signal to the first DC power supply;
applying a DC voltage output from the first DC power supply to the adaptive circuit based on the control signal;
adjusting the capacitance of the at least one variable capacitor based on the DC voltage; and
and transmitting wireless power through the first inductor based on the adjusted capacitance. 12. The method of claim 11,
The step of applying the control signal to the first DC power supply device comprises:
measuring a current flowing in the first inductor; and
and generating the control signal based on information about the measured current flowing in the first inductor. 12. The method of claim 11,
The step of applying the control signal to the first DC power supply includes:
receiving data regarding a current flowing in a second inductor of the external device inductively coupled with the first inductor; and
and generating the control signal based on the received data. 12. The method of claim 11,
The step of applying the control signal to the first DC power supply device comprises:
receiving data on a current flowing through a load of the external device; and
and generating the control signal based on the received data. 12. The method of claim 11,
The wireless power transmission device,
a second DC power supply device and a driving circuit configured to receive DC power output from the second DC power supply device and supply AC power to the resonance circuit;
The step of applying the control signal to the first DC power supply includes:
measuring at least one of an output voltage and a current of the second DC power supply; and
and generating the control signal based on at least one of information about the measured output voltage and information about the output current. 12. The method of claim 11,
The at least one variable capacitor is connected in series or parallel with the first inductor, wireless power transmission method. 12. The method of claim 11,
The at least one variable capacitor is one of a ferroelectric capacitor and a liquid crystal capacitor. A computer program product comprising a computer-readable storage medium,
The storage medium includes an adaptive circuit including at least one variable capacitor, a resonance circuit including a first inductor, and a first DC power supply to a wireless power transmission device for wirelessly transmitting power to an external device. computer program instructions for performing a power transfer method performed by
The power transmission method is
applying a control signal to the first DC power supply;
applying a DC voltage output from the first DC power supply to the adaptive circuit based on the control signal;
adjusting the capacitance of the at least one variable capacitor based on the DC voltage; and
and transmitting wireless power through the first inductor based on the adjusted capacitance.

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