KR20230055720A - Wireless power transmitting apparatus and control method thereof - Google Patents

Abstract

A wireless power transmission device is disclosed. A wireless power transmission device is connected in parallel with a receiver that receives power from the outside, a resonator that converts the power received through the receiver into wireless power and supplies it to a first external device, and the resonator, and converts the power received through the receiver into wireless power. It identifies whether the electrode unit supplied to the second external device and whether or not the second external device and the electrode unit are contact-connected to each other, and controls the electrode unit to provide received power to the second external device when the second external device and the electrode unit are contact-connected. contains a controller that

Description

Wireless power transmission device and its control method { WIRELESS POWER TRANSMITTING APPARATUS AND CONTROL METHOD THEREOF }

The present invention relates to a wireless power transmitter and a control method thereof, and more particularly, to a wireless power transmitter providing wireless power using a plurality of wireless power transmitters and a control method thereof.

Wireless power transfer refers to a technology that can transfer power without wires. It is also called Wi-power because it compares it to Wi-Fi technology that allows you to access the Internet wirelessly anytime, anywhere.

Wireless power transmission and reception methods include the Inductive Power Transfer System (IPTS) method used for wireless charging of smartphones, the Magnetic Resonance System (CMRS) method that is being promoted for use in electric vehicles and high-speed trains, and the space There are various methods, such as the long-distance microwave method, which is being developed for use in photovoltaic power generation.

Recently, thanks to the development of electronic technology, there is a movement to improve the inconvenience of wires and to apply wireless power transmission technology to various types of electronic devices in terms of interiors.

On the other hand, since there is a connection line between the conventional power transmitter and the wireless power transmitter, and the possible separation distance between the wireless power transmitter and the wireless power receiver is only a few cm, even though the wireless power transmission/reception function is used, from the user's point of view There were inconveniences and limitations in not feeling the difference from using a wired power transmission/reception function.

The present disclosure is in accordance with the above-mentioned necessity, and an object of the present disclosure is a wireless power transmitter capable of connecting another wireless power transmitter to the wireless power transmitter and providing power to the other wireless power transmitter, and controlling the same. in providing a way.

A wireless power transmission device according to an embodiment of the present disclosure for achieving the above object is a receiver that receives power from the outside, converts the power received through the receiver into wireless power, and supplies it to a first external device. A resonance unit connected in parallel with the resonance unit, an electrode unit supplying the power received through the receiver to a second external device, and whether or not the second external device and the electrode unit are connected in contact with each other; 2 includes a controller that controls the electrode unit to provide the received power to the second external device when the external device and the electrode unit are contact-connected.

Here, the controller controls the resonator to provide the wireless power to the first external device when it is identified that the first external device is located within a threshold distance from the wireless power transmitter, and the resonator controls the wireless power. Controls the electrode unit to provide the power to the second external device independently of whether it is being provided to the wireless power receiver, wherein the first external device is a wireless power receiver, and the second external device It may be a wireless power transmission device.

The controller may further include a surge protection unit connected in parallel with the resonator unit, and if the controller identifies that the first external device is not located within a threshold distance while providing the wireless power to the first external device, the wireless The resonator unit may be controlled to stop supplying power and the surge prevention unit may be controlled to isolate residual power of the resonator unit.

Here, the surge prevention unit may be implemented with at least one of a single pole double throw (SPDT) relay and a semiconductor switch element.

In addition, the controller may provide the power to the second external device when it is identified that the electrode unit and the receiver provided in the second external device are connected to each other in contact.

In addition, the second external device may be connected in parallel with the wireless power transmitter to receive the power provided to the wireless power transmitter from the outside.

In addition, the wireless power transmitter receives the power from a power supply device, the power supply device identifies an inverter and a magnetization current value of the inverter, and the power supply device provides the magnetization current value based on the magnetization current value. and an OCP controller for identifying the number of wireless power transmitters receiving the power to receive the power and adjusting an Over Current Protection (OCP) level of the power supply device based on the identified number, wherein the OCP level is May be proportional to the number identified.

Here, the OCP controller may identify the magnetizing current value of the inverter based on the falling edge signal of the high-side FET.

In addition, when the first external device receives the power from a resonator that receives the wireless power from the wireless power transmitter, a variable inductor serially connected to the resonator, and another wireless power transmitter, After increasing the inductance value of the variable inductor, a controller may be included to gradually decrease the inductance value to match the operating frequency of the inverter provided in the other wireless power transmitter.

Here, the variable inductor may be implemented as a saturable inductor or a transformer.

A system including a wireless power transmitter and a wireless power receiver, wherein the wireless power transmitter includes: a receiver that receives power from the outside; and converts the power received through the receiver into wireless power to the wireless power receiver. A resonance unit supplied to the resonance unit, an electrode unit connected in parallel with the resonance unit and supplying the power received through the receiver to an external device, and when the external device and the electrode unit are connected in contact, the received power is transferred to the external device and a controller controlling the electrode unit to provide a resonator unit for receiving the wireless power from the wireless power transmitter, a variable inductor serially connected to the resonator unit, and the wireless power transmitter When receiving the power from another wireless power transmitter, increasing the inductance value of the variable inductor in an initial transient state and then gradually decreasing the inductance value to match the operating frequency of an inverter provided in the other wireless power transmitter contains the controller

Meanwhile, a control method of a wireless power transmission device including a receiver, a resonator, and an electrode unit according to an embodiment of the present disclosure includes receiving power from the outside through the receiver, transmitting the power received through the receiver to the wireless converting power into electric power and providing it to a first external device through the resonance unit, identifying whether or not the second external device and the electrode unit are contact-connected to each other, and when the second external device and the electrode unit are contact-connected, the and providing the power to the second external device through an electrode unit.

Here, the providing of the wireless power to the first external device may include supplying the wireless power to the first external device through the resonator when it is identified that the first external device is located within a threshold distance from the wireless power transmitter. In the step of providing the power to the second external device, the power is contacted to the electrode part independently of whether the resonator unit is providing the wireless power to the wireless power receiver. It may be provided as the second external device.

The wireless power transmitter further includes a surge protection unit connected in parallel to the resonator unit, and when the first external device is identified as not located within a threshold distance while providing the wireless power to the first external device, , The method may further include controlling the resonance unit to stop providing the wireless power and controlling the surge prevention unit to isolate residual power of the resonance unit.

Here, the surge prevention unit may be implemented with at least one of a single pole double throw (SPDT) relay and a semiconductor switch element.

In addition, providing the received power to the other wireless power transmission device may include providing the power to the second external device when it is identified that the electrode unit and the receiving unit provided in the second external device are contacted. steps may be included.

In addition, the second external device may be connected in parallel with the wireless power transmitter to receive the power provided to the wireless power transmitter from the outside.

In addition, the step of receiving power from the outside includes receiving the power from a power supply device, wherein the power supply device includes an inverter and an OCP controller, and the OCP controller includes a magnetization current value of the inverter. Identifying, by the OCP controller, identifying the number of wireless power transmitters receiving the power provided by the power supply based on the magnetizing current value, and by the OCP controller based on the identified number The method may further include adjusting an Over Current Protection (OCP) level of the power supply, and the OCP level may be proportional to the number of identified numbers.

Here, identifying the magnetizing current value of the inverter may include identifying, by the OCP controller, the magnetizing current value of the inverter based on a falling edge signal of a high-side FET.

In addition, after the first external device increases the inductance value of the variable inductor included in the wireless power receiver in an initial transient state, the inductance value is adjusted to match the operating frequency of an inverter included in the other wireless power transmitter. A gradual decrease may be further included.

As described above, according to various embodiments of the present disclosure, since each of the plurality of wireless power transmitters does not need to be individually connected to the power supply device, the length, thickness, and number of connection lines can be reduced compared to the prior art, and the user's aesthetic It can increase satisfaction.

When the number of electronic devices capable of receiving wireless power increases indoors, ease of expansion and convenience of the wireless power transmitter may increase.

1 is a diagram for explaining a conventional wireless power transmission device.
2 is a diagram for explaining a wireless power transmission device according to an embodiment of the present disclosure.
3 is a circuit diagram for specifically explaining a wireless power transmission device according to an embodiment of the present disclosure.
4 is a diagram for explaining a power supply device according to an embodiment of the present disclosure.
5 is a diagram for explaining a power supply device according to another embodiment of the present disclosure.
6 is a diagram for explaining a wireless power receiver according to an embodiment of the present disclosure.
7 is a diagram for explaining a magnetization current according to an exemplary embodiment of the present disclosure.
8 is a diagram for explaining OCP (Over Current Protection) according to an embodiment of the present disclosure.
9 is a diagram for explaining an OCP according to an embodiment of the present disclosure.
10 is a diagram for explaining a wireless power receiving apparatus according to an embodiment of the present disclosure.
11 is a diagram for explaining a size of a variable inductor according to an exemplary embodiment of the present disclosure.
12 is a diagram for explaining types of variable inductors according to an exemplary embodiment of the present disclosure.
13 is a flowchart for explaining a control method of a wireless power transmitter according to an embodiment of the present disclosure.

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

The terms used in the embodiments of the present disclosure have been selected from general terms that are currently widely used as much as possible while considering the functions in the present disclosure, but they may vary depending on the intention or precedent of a person skilled in the art, the emergence of new technologies, and the like. . In addition, in a specific case, there is also a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the disclosure. Therefore, terms used in the present disclosure should be defined based on the meaning of the term and the general content of the present disclosure, not simply the name of the term.

In this specification, expressions such as “has,” “can have,” “includes,” or “can include” indicate the existence of a corresponding feature (eg, numerical value, function, operation, or component such as a part). , which does not preclude the existence of additional features.

The expression at least one of A and/or B should be understood to denote either "A" or "B" or "A and B".

Expressions such as "first," "second," "first," or "second," as used herein, may modify various components regardless of order and/or importance, and may refer to one component It is used only to distinguish it from other components and does not limit the corresponding components.

A component (e.g., a first component) is "(operatively or communicatively) coupled with/to" another component (e.g., a second component); When referred to as "connected to", it should be understood that an element may be directly connected to another element, or may be connected through another element (eg, a third element).

Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, the terms "comprise" or "consist of" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other It should be understood that the presence or addition of features, numbers, steps, operations, components, parts, or combinations thereof is not precluded.

In the present disclosure, a “module” or “unit” performs at least one function or operation, and may be implemented in hardware or software or a combination of hardware and software. In addition, a plurality of "modules" or a plurality of "units" are integrated into at least one module and implemented by at least one processor (not shown), except for "modules" or "units" that need to be implemented with specific hardware. It can be.

In this specification, the term user may refer to a person using an electronic device or a device (eg, an artificial intelligence electronic device) using an electronic device.

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

1 is a diagram for explaining a conventional wireless power transmission device.

Referring to FIG. 1 , a power line of a wireless power transmitter (eg, a Tx Module) for providing wireless power to home appliances may receive power from the outside. For example, the power line of the wireless power transmission device may be a power supply (eg, Power Supply) or a power outlet (or power strip) providing commercial power (eg, 90 to 264V). ), etc., and the wireless power transmitter may transmit commercial power to a wireless power receiver (eg, Rx Module).

Here, the wireless power receiver may receive power wirelessly transmitted by the wireless power transmitter (or generate a voltage by induced electromotive force) and provide it to the home appliance. The wireless power receiver may be included as a component in a home appliance that provides a wireless power reception function, or may be electrically connected to the home appliance as a separate module to provide power transmitted by the wireless power transmitter to the home appliance. Of course there is.

As shown in FIG. 1, only when the separation distance between the wireless power transmitter and the wireless power receiver is within several cm, wireless power transmission and reception of a certain efficiency or higher is possible, and long-distance (exceeding several cm) wireless power transmission and reception is possible. There is a problem in which the efficiency drops rapidly.

Therefore, each of the plurality of wireless power transmitters provided in the home should be located adjacent to a home appliance (or a wireless power receiver provided in the home appliance) for providing wireless power, and each of the plurality of wireless power transmitters The power line must be connected to the power supply.

In this case, since a plurality of connection lines are located indoors, aesthetics are spoiled, and a user cannot feel a difference from conventional wired power transmission/reception due to the presence of a plurality of connection lines.

Hereinafter, each of a plurality of wireless power transmitters provided in the house does not need to be directly connected to the power supply device, and the thickness and length of the connection line can be adjusted. Let's explain the power transmission device.

2 is a diagram for explaining a wireless power transmission device according to an embodiment of the present disclosure.

Referring to FIG. 2 , a first wireless power transmitter among a plurality of wireless power transmitters is connected to a power supply device and may receive power from the outside (eg, a power supply device).

In addition, a second wireless power transmitter among a plurality of wireless power transmitters is connected to the first wireless power transmitter, and power provided by the power supply device through the first wireless power transmitter even if not directly connected to the power supply device. can receive

Therefore, the power supply device is connected to the outlet located on the wall by wire, and one of the plurality of wireless power transmitters is connected to the power supply device, and the others are connected to other wireless power transmitters to be expandable. Referring to FIG. 2 , a plurality of wireless power transmission devices may be connected in a cascade form to receive power provided by a power supply device.

As shown in FIG. 2, since each of the plurality of wireless power transmitters does not need to be directly connected to the power supply, the length of the connection line is shortened, and the new wireless power transmitter is connected to the power supply to receive power. Rather, it has the advantage of being easy to expand because power can be received when connected to the wireless power transmitter located last among the plurality of wireless power transmitters.

Hereinafter, the configuration of the wireless power transmission device will be described with reference to a circuit diagram.

3 is a circuit diagram for specifically explaining a wireless power transmission device according to an embodiment of the present disclosure.

Referring to FIG. 3 , the wireless power transmitter 120 receives power from the power supply device 110 .

First, the wireless power transmitter 120 is connected to the power supply device 110 through the receiver 121 and receives power from the power supply device 110 . Next, the wireless power transmitter 120 includes a resonator 122 that converts the received power into wireless power.

The resonator 122 includes a transmission coil, and an induced electromotive force is generated by a voltage applied to the transmission coil or a current flowing through the transmission coil. Here, the induced electromotive force has a unit of voltage.

As will be described later, the receiving coil provided in the wireless power receiving device receives electromagnetic energy from the transmitting coil. For example, the receiving coil may receive wireless power through magnetic coupling with the transmitting coil.

Meanwhile, the wireless power transmitter 120 according to an embodiment of the present disclosure includes a controller, and the controller controls a first external device within a critical distance (eg, several cm) from the wireless power transmitter 120. When identified as located, the resonator 122 may be controlled to provide wireless power to the wireless power receiver. Here, the first external device may include a wireless power receiver. Hereinafter, for convenience of explanation, an external device that receives wireless power from the wireless power transmitter 120 will be collectively referred to as a wireless power receiver.

For example, the wireless power transmitter 120 includes a switch 123, and the controller turns on the switch 123 when it is identified that the wireless power receiver is located within a threshold distance from the wireless power transmitter 120. It can be (switch 123 closed state (Close)). As another example, if it is identified that the wireless power receiver is not located within the threshold distance from the wireless power transmitter 120, the controller may turn off the switch 123 (the switch 123 is open).

For example, the switch 123 is implemented as a physical switch or a reed switch using a magnet. When the wireless power receiver is located within a critical distance from the wireless power transmitter 120, the switch 123 is turned on. state, and if the wireless power receiver is not located within the threshold distance from the wireless power transmitter 120, the switch 123 may be converted to an off state. As another example, the controller performs wireless communication with the wireless power receiver to identify whether the wireless power receiver is located within a threshold distance (eg, based on the strength of a signal received from the wireless power receiver), and identify the wireless power receiver. On or off of the switch 123 may be controlled based on the result.

The wireless power transmitter 120 according to an embodiment includes an electrode unit 124 connected in parallel with a resonator unit 122 . For example, when the electrode unit 124 and the second external device are connected to each other, the controller may provide power received from the power supply device 110 to the second external device through the electrode unit 124 . Here, the second external device may be another wireless power transmission device. For example, another wireless power transmitter has the same or similar configuration as the wireless power transmitter 120, converts power received from the outside into wireless power, and transfers power to an external device (eg, another wireless power receiver). can supply Hereinafter, for convenience of description, an external device that receives power through the electrode unit 124 of the wireless power transmitter 120 is collectively referred to as another wireless power transmitter.

Referring to FIG. 3 , among a plurality of wireless power transmitters, a first wireless power transmitter 120-1 is connected to a power supply 110, and a second wireless power transmitter 120-2 is a first wireless power transmitter 120-2. It is connected to the power transmission device 120-1. In this case, the first wireless power transmitter 120-1 converts the power received from the power supply device 110 into wireless power, and the wireless power receiver positioned adjacent to the first wireless power transmitter 120-1. can be provided with In addition, since the electrode unit 124 of the first wireless power transmitter 120-1 and the receiving unit of the second wireless power transmitter 120-2 are contact-connected, the first wireless power transmitter 120-1 may provide the power received from the power supply device 110 to the second wireless power transmitter 120-2. Here, the contact connection may mean that the electrode unit 124 of the first wireless power transmitter 120-1 and the receiver unit of the second wireless power transmitter 120-2 are physically connected or bound.

Meanwhile, the first wireless power transmitter 120-1 is independent of whether wireless power is being provided to the wireless power receiver, the electrode unit 124 of the first wireless power transmitter 120-1 and the second When the receiving unit of the wireless power transmitter 120-2 is connected, the first wireless power transmitter 120-1 transfers the power received from the power supply device 110 to the second wireless power transmitter 120-2. can be provided with

Although not shown in FIG. 3, the second wireless power transmitter 120-2 also converts the power received from the power supply device 110 through the first wireless power transmitter 120-1 into wireless power to generate power. 2 may be provided to a wireless power receiver located adjacent to the wireless power transmitter 120-2. In addition, the second wireless power transmitter 120-2 is also provided in the electrode unit provided in the second wireless power transmitter 120-2 and in another wireless power transmitter (eg, the third wireless power transmitter). When the received unit is connected, the power received from the power supply device 110 may be provided to other wireless power transmitters.

That is, each of a plurality of wireless power transmitters connected in parallel in a cascade form may receive power from the power supply device 110 .

Referring to FIG. 3 , the wireless power transmitter 120 may include a resonator 122 and a surge prevention unit 125 connected in parallel.

According to an embodiment, if the wireless power transmitter 120 is providing wireless power to the wireless power receiver and it is identified that the wireless power receiver is not located within the threshold distance, the controller 122 transmits wireless power. The switch 123 may be turned off so as to stop providing (or not output). In this case, the residual power of the resonator 122 (for example, the remaining electromagnetic energy of the transmission coil) may be discharged through the anti-surge unit. Here, the surge prevention unit 125 may be referred to as a surge protector. The surge prevention unit 125 may discharge residual power of the resonance unit 122 .

According to an embodiment of the present disclosure, the surge prevention unit 125 can be implemented with various devices. For example, the surge prevention unit 125 may be implemented with at least one of a single pole double throw (SPDT) relay switch and a semiconductor switch element. For example, since the parallel switch operates complementary to the series switch, a freewheeling path of the current flowing in the resonator 122 toward the parallel switch is formed, so that excessive voltage may not be applied to the switch, and residual power may be reduced by the switch. Vibration can be prevented by resistance and coil resistance.

However, this is an example and is not limited thereto. Of course, the surge prevention unit 125 can be implemented by combining one or more elements such as a gas discharge tube, an air gap, a thyristor, a suppressor diode, and a varistor. In addition to the above examples, the surge prevention unit 125 can be implemented with various devices capable of isolating residual power.

4 is a diagram for explaining a power supply device according to an embodiment of the present disclosure.

Referring to FIG. 4 , the power supply device 110 is wired to a wall outlet and can receive commercial power. The power supply device 110 includes an EMI filter, a Power Factor Correction (PFC) circuit, an electrode unit 111, an inverter 112, and an Over Current Protection (OCP) controller 113.

The EMI filter rectifies and smooths commercial power and outputs it as a DC voltage of a certain level. A half-wave or full-wave rectification circuit may be used for rectification, and a capacitor may be connected in parallel to the output of the rectification circuit for smoothing.

A power factor correction (PFC) circuit can reduce the phase difference between DC voltage and DC current input through an EMI filter. Therefore, power efficiency can be increased by offsetting the reactive power.

The inverter 112 may convert the DC voltage output after power factor correction from the PFC circuit back into an AC voltage and output the converted AC voltage to the electrode unit 111 . That is, when the electrode unit 111 provided in the power supply device 110 and the receiver 121 provided in the wireless power transmitter 120 are connected, the power supply device 110 is transferred to the wireless power transmitter 120. power can be provided. Subsequently, the resonator 122 provided in the wireless power transmitter 120 may transmit electromagnetic energy to the wireless power receiver.

Meanwhile, the power supply device 110 according to an embodiment of the present disclosure may not include a DC/DC converter such as an Inductor-Inductor-Capacitor (LLC) converter or a flyback converter.

Referring to FIG. 4 , the inverter 112 may be implemented as a Half-Bridge inverter including a plurality of switches. The Half-Bridge inverter controls two switches, high-side and low-side, and can convert DC voltage back to AC voltage using the input voltage of Vdc/2 (current of I).

5 is a diagram for explaining a power supply device according to another embodiment of the present disclosure.

Referring to FIG. 5 , the inverter 112 may be implemented as a Full-Bridge inverter including a plurality of switches. The Full-Bridge inverter can convert DC voltage back to AC voltage using Vdc input voltage (I/2 current) by controlling four switches.

Hereinafter, the OCP (Over Current Protection) controller 113 of the power supply device 110 identifies the number of wireless power transmitters 120 receiving power from the power supply device 110, and based on the identified number. Thus, an embodiment of controlling the OCP level will be described.

6 is a diagram for explaining a wireless power receiver according to an embodiment of the present disclosure.

Referring to FIG. 6 , the first wireless power transmitter 120-1 may provide wireless power to the first wireless power receiver 200-1 adjacent to the first wireless power transmitter 120-1. . Subsequently, the first wireless power receiver 200-1 may provide power to a load (eg, a load of an electronic device (display device, etc.)).

In addition, while the second wireless power transmitter 120-2 is connected to the first wireless power transmitter 120-1, the second wireless power receiver 200-2 is connected to the second wireless power transmitter 120. -1), the second wireless power transmitter 120-2 may provide wireless power to the second wireless power receiver 200-2. Subsequently, the second wireless power receiver 200-2 may provide power to a load (eg, a load of an electronic device (display device, etc.)).

The waveform of the current flowing through the switch of the inductor 112 of the power supply device 110 according to the operation shown in FIG. 6 will be described in detail with reference to FIG. 7 .

7 is a diagram for explaining a magnetization current according to an exemplary embodiment of the present disclosure.

7(a) shows the first wireless power transmitter 120-1 and the first wireless power transmitter 120-1 when providing wireless power to the first wireless power receiver 200-1. It is a graph showing the waveform of the current flowing through the first wireless power receiver 200-1.

The current (I _LIkg1 ) flowing in the first wireless power transmitter 120-1 (ie, the primary circuit) is the current flowing in the magnetizing inductor (L _m1 ) of the first wireless power transmitter 120-1. (That is, the sum of the magnetizing current (I _Lm1 )) and the current flowing in the inductor (L _Iks1 ) provided in the first wireless power receiver 200-1 (ie, the current flowing in the secondary circuit (I _LIks1 )) ( I _Lm1 + I _LIks1 ).

7(b) shows the second wireless power transmitter 120-2 and the second wireless power transmitter 120-2 when providing wireless power to the first wireless power receiver 200-2. It is a graph showing the waveform of the current flowing through the second wireless power receiver 200-2.

The current (I _LIkg2 ) flowing in the second wireless power transmitter 120-2 (ie, the primary circuit) is the current flowing in the magnetizing inductor (L _m2 ) of the second wireless power transmitter 120-2. (That is, the sum of the magnetizing current (I _Lm2 )) and the current flowing in the inductor (L _Iks2 ) provided in the second wireless power receiver 200-2 (ie, the current flowing in the secondary circuit (I _LIks2 )) ( I _Lm2 + I _LIks2 ).

Referring to (a) and (b) of FIG. 7 , the waveform of the current (I _LIkg ) flowing through the wireless power transmitter 120 is the current flowing through the magnetizing inductor (Lm) of the wireless power transmitter 120. It is equal to the sum of (I _Lm ) and the current (I _LIks ) flowing through the wireless power receiver 200 . Here, the current (I _LIks ) flowing through the wireless power receiver 200 is the resonance current required by the wireless power receiver 200 (eg, an electronic device to which the wireless power receiver 200 provides power). (eg, a resonance current required for operation of a TV).

From the perspective of the power supply 110, the first wireless power transmitter 120-1 and the second wireless power transmitter 120-2 are connected in parallel, and the inverter 112 of the power supply 110 The waveform of the current flowing through the switch may be represented by a waveform of a sum of currents flowing through each of the first wireless power transmitter 120-1 and the second wireless power transmitter 120-2.

Referring to (c) of FIG. 7, the current IR flowing through the switch Gate H of the inverter 112 _of the power supply 110 is the current flowing through the first wireless power transmitter 120-1 ( It may be the sum of I _LIkg1 ) and the current (I _LIkg2 ) flowing through the second wireless power transmitter 120-2.

On the other hand, as shown in (c) of FIG. 7, the current IR flowing through the switch (Gate H) of the inverter 112 of the power supply 110 at the time when the resonance ends (see gray area) _is It may be the sum of the magnetization current (I _Lm1 ) of one wireless power transmitter 120-1 and the magnetization current (I _Lm2 ) of the second wireless power transmitter 120-2.

That is, the OCP controller 113 controls the first wireless power transmitter 200-1 and the second wireless power transmitter 200-2 regardless of the size of the resonance current required by each of the first wireless power receiver 200-1 and the second wireless power receiver 200-2. A wireless power transmitter that receives power from the power supply 110 based on the sum of the magnetization current (I _Lm1 ) of the 120-1) and the magnetization current (I _Lm2 ) of the second wireless power transmitter 120-2 The number of (120) and whether or not the wireless power transmitter 120 is providing wireless power to the adjacent wireless power receiver 200 may be identified.

8 is a diagram for explaining OCP (Over Current Protection) according to an embodiment of the present disclosure.

The OCP controller 113 may detect whether an overcurrent exceeding an OCP level flows through the power supply device 110 to protect the power supply device 110 .

As described above, due to the resonance current required by the wireless power receiver 200 (that is, the current required for the operation of the load (eg, TV)), the power supply device 110 exceeds the OCP level. When an overcurrent flows, protection of the power supply device 110 may be required.

In contrast, when a plurality of wireless power transmitters 120 are connected to the power supply device 110 and each of the plurality of wireless power transmitters 120 provides wireless power to the wireless power receiver 200, Due to the increase in magnetization current flowing through each of the plurality of wireless power transmitters 120, the OCP controller 113 supplies the OCP to the power supply device 110 even though the resonance current required by the wireless power receiver 200 is not large. Since overcurrent exceeding the level flows, it can be identified as a situation in which protection of the power supply device 110 is required.

As the plurality of wireless power transmitters 120 are connected to the power supply 110, the OCP controller 113 according to an embodiment of the present disclosure determines whether overcurrent exceeding the OCP level flows in the power supply 110. Power provided by the power supply 110 to identify whether overcurrent exceeding the OCP level flows in the power supply 110 due to the resonance current required by the wireless power receiver 200, rather than to identify It is possible to identify the number of wireless power transmitters 120 receiving the , and adjust the OCP level based on the identified number. Here, the OCP level may be proportional to the identified number.

First, referring to FIG. 8 , the OCP controller 113 may identify a magnetizing current value based on the magnitude of the current _IR flowing through the switch Gate H of the inverter 112 .

9 is a diagram for explaining an OCP according to an embodiment of the present disclosure.

For example, the OCP controller 113 may identify a magnetizing current value based on a falling edge signal of a high-side FET of the inverter 112 .

According to an embodiment, as the number of wireless power transmitters 120 receiving power provided by the power supply 110 increases, the magnitude of the falling edge signal of the high-side FET of the inverter 112 (or the magnetization current value) may also increase. Therefore, as shown in FIG. 8 , the OCP controller 113 may increase the OCP level stepwise as the level of the falling edge signal of the high-side FET increases.

10 is a diagram for explaining a wireless power receiving apparatus according to an embodiment of the present disclosure.

The resonant coil receiver of the wireless power receiver 200 receives electromagnetic energy from the resonator 122 of the wireless power transmitter 120 . For example, the resonant coil receiver may receive wireless power through magnetic coupling with the resonator 122 .

The rectifier may rectify power received through the resonant coil receiver. For example, the rectifier may generate DC current by rectifying the AC current received by the resonant coil receiver. For example, the rectifier may rectify and smooth the AC voltage provided from the resonant coil receiver again, and convert it into a DC voltage.

The switch may operate together with the switch 123 included in the wireless power transmitter 120. For example, if the switch is adjacent to the wireless power transmitter 120, turn on the switch 123 provided in the wireless power transmitter 120 or switch on the controller provided in the wireless power transmitter 120 ( 123) may provide a signal for turning on.

Subsequently, the wireless power receiver 200 may provide the rectified power to an electronic device or a load (eg, a power board of a TV). The wireless power receiver 200 may provide power required for driving a load.

In particular, the wireless power receiver 200 according to an embodiment of the present disclosure may include a variable inductor.

11 is a diagram for explaining a size of a variable inductor according to an exemplary embodiment of the present disclosure.

First, the inverter 112 included in the power supply device 110 may include a soft start circuit. For example, when the first wireless power receiver 200-1 is adjacent to the first wireless power transmitter 120-1 and receives wireless power from the first wireless power transmitter 120-1, the initial transient state Since the capacitor included in the first wireless power receiver 200-1 is not charged in , the output voltage V _out of the first wireless power receiver 200-1 is 0 [V]. At this time, there is a problem in that inrush current (overcurrent) flows in the inverter 112 because the power provided by the power supply device 110, that is, the input voltage, is all applied to the leakage inductance.

Therefore, the soft start circuit provided in the inverter 112 drives the switch of the inverter 112 at a relatively high frequency compared to the resonance frequency in the initial transient state (or driven at a relatively small pulse width modulation (PWM) duty ratio). Then, as time elapses, the switch can be operated by lowering the driving frequency (or by increasing the PWM duty ratio) (steady state).

6 according to an embodiment of the present disclosure, while the first wireless power transmitter 120-1 transmits wireless power to the first wireless power receiver 200-1, the first wireless It is assumed that the second wireless power transmitter 120-2 connected to the power transmitter 120-1 starts to transmit wireless power to the second wireless power receiver 200-2 located within a critical distance. can

In this case, the first wireless power transmitter 120-1 and the first wireless power receiver 200-1 are in a normal state, and the switch of the inverter 112 is driven under the control of a soft start circuit. The frequency may correspond to the resonant frequency.

Since the capacitor included in the second wireless power receiver 200-2 is not charged, the second wireless power transmitter 120-2 and the second wireless power receiver 200-2 are in an initial transient state. , The switch of the inverter 112 should be driven at a relatively high frequency compared to the resonance frequency according to the control of the soft start circuit, but the first wireless power transmitter 120-1 and the first wireless power receiver ( Since 200-1) is in a normal state, the driving frequency of the switch of the inverter 112 cannot be changed to a high frequency.

Therefore, the wireless power receiver 200 according to an embodiment of the present disclosure includes a variable inductor, and adjusts the inductance value of the variable inductor so that the driving frequency of the switch of the inverter 112 is at a frequency relatively high compared to the resonance frequency. It can provide the same effect as gradually reaching the resonance frequency.

For example, referring to FIG. 6 , the second wireless power receiver 200-2 may increase the inductance value of the variable inductor in an initial transient state. In this case, as shown in FIG. 11, when the frequency ratio (Fs/Fr) of the driving frequency (Fs) of the switch and the resonant frequency (Fr) is 1, increasing the inductance value of the variable inductor increases the driving frequency (Fs) of the switch. ) is maintained, since the resonant frequency (Fr) decreases, the switch of the inverter 112 is driven at a relatively high frequency compared to the original resonant frequency to provide the same effect as the gain (GA _AC ) decreases. .

Subsequently, the second wireless power receiver 200-2 gradually reduces the inductance value of the variable inductor and matches the resonance frequency Fr to the original resonance frequency while maintaining the driving frequency Fs of the switch. , the soft start method may provide the same effect as that of providing power to the second wireless power receiver 200-2.

12 is a diagram for explaining types of variable inductors according to an exemplary embodiment of the present disclosure.

Referring to FIG. 12 , the variable inductor included in the wireless power receiver 200 may be implemented as a saturable inductor or a transformer.

13 is a flowchart for explaining a control method of a wireless power transmitter according to an embodiment of the present disclosure.

In the method for controlling a wireless power transmission device including a receiver, a resonance unit, and an electrode unit according to an embodiment of the present disclosure, first, power is received from the outside through the receiver (S1310).

Subsequently, the power received through the receiver is converted into wireless power and provided to the first external device through the resonator (S1320).

Subsequently, whether or not the second external device and the electrode unit are mutually contacted is identified (S1330).

Subsequently, when the second external device and the electrode unit are contact-connected, power is provided to the second external device through the electrode unit (S1340).

Here, step S1320 of providing wireless power to the first external device includes providing wireless power to the first external device through a resonator when it is identified that the first external device is located within a threshold distance from the wireless power transmitter. In step S1340 of providing power to the second external device, power may be provided to the second external device contact-connected to the electrode unit independently of whether or not the resonance unit is providing wireless power to the wireless power receiver.

In addition, the wireless power transmitter further includes a surge protector connected in parallel with the resonator, and the control method according to an embodiment includes not placing the first external device within a critical distance while providing wireless power to the first external device. If it is identified that the wireless power is not provided, the method may further include controlling the resonance unit to stop providing wireless power and controlling the surge prevention unit to discharge residual power of the resonance unit.

Here, the surge prevention unit may be implemented with at least one of a single pole double throw (SPDT) relay and a semiconductor switch element.

In addition, the step S1340 of providing the received power to the second external device may include providing the power to the second external device when it is identified that the electrode unit and the receiving unit provided in the second external device are connected to each other in contact. .

According to an embodiment, the second external device may be connected in parallel with the wireless power transmitter and receive power provided to the wireless power transmitter from the outside.

Step S1310 of receiving power from the outside according to an embodiment includes receiving power from a power supply device, the power supply device includes an inverter and an OCP controller, and the OCP controller determines the magnetizing current value of the inverter. Identifying, by the OCP controller, identifying the number of wireless power transmitters receiving power provided by the power supply based on the magnetizing current value, and by the OCP controller based on the identified number of OCP (Over OCP) of the power supply Current Protection) level, and the OCP level may be proportional to the identified number.

Here, identifying the magnetizing current value of the inverter may include identifying, by the OCP controller, the magnetizing current value of the inverter based on the falling edge signal of the high-side FET.

In a control method according to an embodiment of the present disclosure, after a first external device increases the inductance value of a variable inductor included in a wireless power receiver in an initial transient state, the operating frequency of an inverter provided in another wireless power transmitter is changed. A step of gradually decreasing the value of the inductance to match may be further included.

However, it goes without saying that various embodiments of the present disclosure may be applied to all electronic devices capable of transmitting/receiving wireless power as well as a wireless power transmission device.

Meanwhile, various embodiments described above may be implemented in a recording medium readable by a computer or a similar device using software, hardware, or a combination thereof. In some cases, the embodiments described herein may be implemented by a processor itself. According to software implementation, embodiments such as procedures and functions described in this specification may be implemented as separate software modules. Each of the software modules may perform one or more functions and operations described herein.

Meanwhile, computer instructions for performing the processing operation of the wireless power transmitter according to various embodiments of the present disclosure described above may be stored in a non-transitory computer-readable medium. . When the computer instructions stored in the non-transitory computer readable medium are executed by the processor of the specific device, the processing operation in the audio output device 100 according to various embodiments described above is performed by the specific device.

A non-transitory computer readable medium is a medium that stores data semi-permanently and is readable by a device, not a medium that stores data for a short moment, such as a register, cache, or memory. Specific examples of the non-transitory computer readable media may include CD, DVD, hard disk, Blu-ray disk, USB, memory card, ROM, and the like.

Although the preferred embodiments of the present disclosure have been shown and described above, the present disclosure is not limited to the specific embodiments described above, and is common in the technical field belonging to the present disclosure without departing from the gist of the present disclosure claimed in the claims. Of course, various modifications are possible by those with knowledge of, and these modifications should not be individually understood from the technical spirit or perspective of the present disclosure.

110: power supply device 120: wireless power transmission device
200: wireless power receiving device

Claims (20)

In the wireless power transmission device,
a receiving unit that receives power from the outside;
a resonance unit that converts the power received through the receiver into wireless power and supplies it to a first external device;
an electrode unit connected in parallel with the resonance unit and supplying the power received through the receiver to a second external device; and
Identify whether or not the second external device and the electrode unit are connected in contact with each other;
and a controller configured to control the electrode unit to provide the received power to the second external device when the second external device and the electrode unit are contact-connected. According to claim 1,
The controller,
When it is identified that a first external device is located within a threshold distance from the wireless power transmitter, controlling the resonator to provide the wireless power to the first external device;
Controlling the electrode unit to provide the power to the second external device independently of whether the resonance unit is providing the wireless power to the wireless power receiver;
The first external device is a wireless power receiver,
The second external device is another wireless power transmission device, a wireless power transmission device. According to claim 1,
It further includes; a surge protection unit connected in parallel with the resonator unit;
The controller,
When it is identified that the first external device is not located within a threshold distance while providing the wireless power to the first external device, the resonator is controlled to stop providing the wireless power and the remaining power of the resonator is oscillated. A wireless power transmission device that controls a surge protection unit to According to claim 3,
The surge prevention unit,
A wireless power transmission device implemented as at least one of a single pole double throw (SPDT) relay or a semiconductor switch element. According to claim 1,
The controller,
When the electrode unit and the receiver provided in the second external device are identified as contact-connected, the wireless power transmitter provides the power to the second external device. According to claim 1,
The second external device,
A wireless power transmitter connected in parallel with the wireless power transmitter to receive the power provided to the wireless power transmitter from the outside. According to claim 1,
The wireless power transmission device,
receiving the power from a power supply;
The power supply device,
inverter; and
Identifying the magnetizing current value of the inverter;
Identifying the number of wireless power transmitters receiving the power provided by the power supply based on the magnetization current value;
An OCP controller for adjusting an Over Current Protection (OCP) level of the power supply device based on the identified number; includes,
The OCP level is proportional to the identified number, wireless power transmission device. According to claim 7,
The OCP controller,
A wireless power transmission device for identifying the magnetizing current value of the inverter based on the falling edge signal of the high-side FET. According to claim 1,
The first external device,
a resonance unit receiving the wireless power from the wireless power transmitter;
a variable inductor serially connected to the resonator; and
When receiving the power from another wireless power transmitter, increasing the inductance value of the variable inductor in an initial transient state and then gradually decreasing the inductance value to match the operating frequency of an inverter provided in the other wireless power transmitter A wireless power transmission device comprising a; controller. According to claim 9,
The variable inductor,
A wireless power transmission device implemented as a saturable inductor or a transformer. In a system including a wireless power transmitter and a wireless power receiver,
The wireless power transmission device,
a receiving unit that receives power from the outside;
a resonance unit that converts the power received through the receiver into wireless power and supplies it to the wireless power receiver;
an electrode unit connected in parallel with the resonance unit and supplying the power received through the receiver to an external device; and
A controller controlling the electrode unit to provide the received power to the external device when the external device and the electrode unit are contact-connected;
The wireless power receiver,
a resonance unit receiving the wireless power from the wireless power transmitter;
a variable inductor serially connected to the resonator; and
When the wireless power transmitter receives the power from another wireless power transmitter, the inductance value of the variable inductor is increased in an initial transient state, and then the inductance is matched to the operating frequency of the inverter provided in the other wireless power transmitter. A system comprising: a controller that gradually reduces the value of In the control method of a wireless power transmission device including a receiver, a resonator, and an electrode,
Receiving power from the outside through the receiver;
converting the power received through the receiver into wireless power and providing the wireless power to a first external device through the resonator;
identifying whether or not the second external device and the electrode unit are contact-connected; and
and providing the power to the second external device through the electrode unit when the second external device and the electrode unit are contact-connected. According to claim 12,
Providing the wireless power to the first external device includes:
When it is identified that the first external device is located within a threshold distance from the wireless power transmitter, providing the wireless power to the first external device through the resonator;
Providing the power to the second external device includes:
The control method of claim 1 , wherein the resonator provides the power to the second external device contacted to the electrode part independently of whether or not the resonator is providing the wireless power to the wireless power receiver. According to claim 12,
The wireless power transmission device,
It further includes; a surge protection unit connected in parallel with the resonator unit;
controlling the resonator to stop providing the wireless power when it is identified that the first external device is not located within a threshold distance while providing the wireless power to the first external device; and
Controlling the surge prevention unit to isolate residual power of the resonance unit; further comprising a control method. According to claim 14,
The surge prevention unit,
A control method implemented with at least one of a Single Pole Double Throw (SPDT) relay or a semiconductor switch element. According to claim 12,
Providing the received power to the second external device includes:
and providing the electric power to the second external device when it is identified that the electrode unit and the receiver provided in the second external device are contact-connected. According to claim 12,
The second external device,
A control method for receiving the power provided to the wireless power transmitter from the outside by being connected in parallel with the wireless power transmitter. According to claim 12,
The step of receiving power from the outside,
Receiving the power from a power supply; includes,
The power supply includes an inverter and an OCP controller,
identifying, by the OCP controller, a magnetizing current value of the inverter;
Identifying, by the OCP controller, the number of wireless power transmitters receiving the power provided by the power supply based on the magnetization current value; and
Further comprising, by the OCP controller, adjusting an Over Current Protection (OCP) level of the power supply device based on the identified number,
The OCP level is proportional to the identified number, the control method. According to claim 18,
The step of identifying the magnetizing current value of the inverter,
And identifying, by the OCP controller, a magnetizing current value of the inverter based on a falling edge signal of the high-side FET. According to claim 12,
After the first external device increases the inductance value of the variable inductor included in the wireless power receiver in an initial transient state, the inductance value is gradually decreased to match the operating frequency of the inverter included in the other wireless power transmitter The step of doing; further comprising a control method.

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