Portable wireless power transmitter, wireless power transmission system, and wireless power transmission method

Abstract

To provide a power transmitter that can transmit power to a power receiver more easily, and a wireless power supply system equipped with said power transmitter. [Solution] One aspect of the present disclosure is a portable wireless power transmitter that has a housing that can be carried by a user and wirelessly supplies power to a power receiver, the portable wireless power transmitter comprising, within the housing: a battery unit for storing power; a charge / discharge circuit for supplying charging power to the battery unit and for extracting discharge power from the battery unit; an operation unit for receiving user operations; a power transmission unit for transmitting power transmission radio waves using power supplied from the battery unit; and a control unit for controlling the charge / discharge circuit to extract discharge power from the battery unit and supply it to the power transmission unit based on operations received by the operation unit.

Description

Technical Field

[0001] The present invention relates to a portable wireless power transmitter, a wireless power transmission system, and a wireless power transmission method.

Background Art

[0002] Conventionally, a technology for supplying power from a wireless power transmitter to a power receiver by wireless power feeding is known. For example, Patent Document 1 describes a wireless rechargeable battery, and discloses a configuration in which an antenna is provided on a casing of the wireless rechargeable battery. This enables the power receiver to be charged wirelessly.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] However, most wireless power transmitters that perform wireless power transmission are installed at fixed positions. Furthermore, since the transmittable distance of wireless power transmitters is limited, power transmission may not be possible depending on the distance from the power receiver. Furthermore, when using an existing wireless power transmitter, it is necessary to establish a wireless connection between the wireless power transmitter and the power receiver and perform authentication in advance. Therefore, power transmission cannot be performed using an unregistered wireless power transmitter or power receiver. For example, power transmission between the wireless power transmitter and the power receiver may not be possible due to a communication failure or the like, or power transmission may not be possible to a power receiver installed at a location far from the wireless power transmitter.

[0005] This disclosure is made in view of these circumstances and aims to provide a portable wireless power transmitter that can transmit power to a power receiver more easily, a wireless power transmission system equipped with the portable wireless power transmitter, and a wireless power transmission method. [Means for solving the problem]

[0006] This disclosure has been made to solve the above-mentioned problems, and one aspect of this disclosure is a portable wireless power transmitter that has a housing that can be carried by a user and wirelessly supplies power to a power receiver, the portable wireless power transmitter comprising, within the housing, a battery unit for storing power, a charge / discharge circuit for supplying charging power to the battery unit and for extracting discharge power from the battery unit, an operation unit for receiving user operations, a power transmission unit for transmitting power transmission radio waves using power supplied from the battery unit, and a control unit for controlling the charge / discharge circuit to extract discharge power from the battery unit and supply it to the power transmission unit based on operations received by the operation unit.

[0007] Another aspect of the present disclosure is a portable wireless power transmitter comprising a housing carried by a user and wirelessly supplying power to a power receiver, wherein the housing includes: a battery unit for storing power; a charge / discharge circuit for supplying charging power to the battery unit and for extracting discharge power from the battery unit; an operation unit for receiving user input; a power transmission unit for transmitting power signals using power supplied from the battery unit; a control unit for controlling the charge / discharge circuit to extract discharge power from the battery unit and supply it to the power transmission unit based on the operation received by the operation unit; and a power transmission control unit that transmits a startup log in response to the device being started. A wireless power transmission system comprising: a portable wireless power transmitter comprising a communication unit that transmits to a system and receives coordination information from the power transmission control system based on the operation of electronic equipment connected to the power receiver; a power transmission control system that receives the startup log from the portable wireless power transmitter and transmits coordination information from the electronic equipment connected to the power receiver based on the operation of the electronic equipment to the portable wireless power transmitter; a power receiver that receives radio waves transmitted from the portable wireless power transmitter; and electronic equipment that operates using power supplied from the power receiver and transmits the coordination information to the power transmission control system.

[0008] Another aspect of the present disclosure is a wireless power transmission method comprising the steps of: starting up a portable wireless power transmitter and transmitting a startup log to a power transmission control system; the portable wireless power transmitter starting to transmit a power transmission radio wave to a power receiver; an electronic device operating with power supplied from the power receiver and transmitting coordination information to the power transmission control system; the power transmission control system transmitting the coordination information to the portable wireless power transmitter; and the portable wireless power transmitter stopping the transmission of a power transmission radio wave in response to receiving the coordination information. [Effects of the Invention]

[0009] According to one aspect of the present invention, it is possible to provide a power transmitter that can more easily transmit power to a power receiver, and a wireless power supply system equipped with the power transmitter. [Brief explanation of the drawing]

[0010] [Figure 1] This is a block diagram showing one example configuration of the wireless power supply system 1 in an embodiment. [Figure 2] A block diagram showing another example of the wireless power supply system 1 in the embodiment. [Figure 3] This is a sequence diagram showing an example of the processing of the wireless power supply system 1 in the embodiment. [Modes for carrying out the invention]

[0011] Hereinafter, a portable wireless power transmitter, a wireless power transmission system, and a wireless power transmission method to which the present invention is applied will be described with reference to the drawings.

[0012] Figure 1 is a block diagram showing one example configuration of the wireless power supply system 1 in an embodiment. The wireless power supply system 1 comprises, for example, a portable wireless power transmitter 100, a portable terminal device 200, a power receiver 300, and an electronic device 400. The portable wireless power transmitter 100 and the portable terminal device 200 are carried by the user. The portable wireless power transmitter 100 and the portable terminal device 200 are connected by existing wireless communication technology. In this embodiment, the portable terminal device 200 is a wireless communication device equipped with communication functions, such as a smartphone. The electronic device 400 is various devices that operate using power supplied from the power receiver 300, such as an IoT device. In this embodiment, the portable wireless power transmitter 100, the power receiver 300, and the electronic device 400 correspond to a wireless power transmission system that operates by wireless power transmission, and function as a configuration that realizes a wireless power transmission method. Although Figure 1 shows a portable wireless power transmitter 100, a portable terminal device 200, a power receiver 300, and an electronic device 400, it is not essential to include these components, and a portable wireless power transmitter to which the present invention is applied can be realized with just the portable wireless power transmitter 100 alone.

[0013] In this embodiment, the portable wireless transmitter 100 and the receiver 300 transmit power using existing wireless communication methods, such as microwaves. The receiver 300 and the electronic device 400 may exchange information with each other using existing wireless communication technologies such as WiFi®, BLE (Bluetooth Low Energy), and LPWA (Low Power Wide Area), and the portable wireless transmitter 100 and the receiver 300 may exchange information with each other using existing wireless communication technologies such as WiFi®.

[0014] The portable wireless power transmitter 100 provides wireless power to the power receiver 300 by transmitting radio waves to the power receiver 300. The portable wireless power transmitter 100 includes a housing 100A that is carried by the user. The portable wireless power transmitter 100 comprises a battery unit 102, a charge / discharge circuit 104, an operation unit 106, a power transmission unit 108, and a control unit 110, all housed in a casing 100A.

[0015] The battery unit 102 includes a rechargeable battery for storing power. The charge / discharge circuit 104 includes a circuit that supplies charging power to the battery unit 102 and a circuit that extracts discharge power from the battery unit 102. The charge / discharge circuit 104 charges the battery unit 102 with power from the commercial power supply in response to, for example, the connection of a commercial power supply to the charging terminal. The charge / discharge circuit 104 also supplies power extracted by discharging the battery unit 102 during wireless power transmission to the power transmission unit 108. The operation unit 106 accepts user input. The operation unit 106 includes, for example, an operation button 106a and a detection circuit that detects the operation of the operation button 106a and outputs a detection signal to the control unit 110. The power transmission unit 108 is a communication circuit that includes, for example, a power transmission antenna and an analog circuit that supplies power to the power transmission antenna. The power transmission unit 108 transmits power transmission radio waves using power supplied from the battery unit 102 via the charge / discharge circuit 104. The power transmission unit 108 also controls, for example, the amplitude, frequency, and direction of the power transmission radio waves. The control unit 110 is an integrated circuit or the like that operates in accordance with a preset program or the like. The control unit 110 controls the charging / discharging circuit 104 to extract discharged power from the battery unit 102 and supply the discharged power to the power transmission unit 108 based on an operation received by the operation unit 106.

[0016] It is preferable that the control unit 110 controls the power transmission unit 108 to regulate at least one of the transmission direction θ, transmission distance D, transmission power, and transmission frequency of power transmission radio waves to be transmitted to the power receiver 300 based on regulation information stored in the storage unit 120. For example, the control unit 110 may perform beamforming processing to cause radio waves to be transmitted in the transmission direction θ in accordance with the regulation information. The regulation information is set, for example, in accordance with laws regulating wireless communication specifications such as radio laws. Note that the regulation information may be updated in accordance with the regulation information, the region where the portable wireless power transmitter 100 is used, or the like.

[0017] The portable wireless power transmitter 100 may include an acquisition unit 112, a position setting unit 114, and a presentation unit 116. The acquisition unit 112 is, for example, a wireless communication circuit that communicates with the portable wireless power transmitter 100. The acquisition unit 112 establishes a communication connection with a portable terminal device 200 carried by a user, acquires regulation information from the portable terminal device 200, and causes the regulation information to be stored in the storage unit 120. The acquisition unit 112 may cooperate with the portable terminal device 200 to share the power transmission status of the portable wireless power transmitter 100, information transmitted from the power receiver 300 to the power transmission control system 700, and the like.

[0018] The position setting unit 114 sets the power transmission position of the portable wireless power transmitter 100 based on the regulation information acquired by the acquisition unit 112. The position setting unit 114 sets position information including a distance to the power receiver 300 and an angle relative to the power receiver 300 such that, for example, the regulation indicated by the regulation information is satisfied and the position falls within the transmittable range of the portable wireless power transmitter 100. The position setting unit 114 may set the power transmission position of the portable wireless power transmitter 100 using the angle and distance of the portable terminal device 200 relative to the power receiver 300 detected by an angle sensor and a distance sensor provided in the portable terminal device 200.

[0019] The presentation unit 116 presents the power transmission position set by the position setting unit 114. The presentation unit 116 is, for example, a mechanism that performs display or outputs sound in different forms depending on whether the position of the portable wireless power transmitter 100 is included in the range of the position set by the position setting unit 114 or is not included in the range of the position set by the position setting unit 114. Furthermore, the portable wireless power transmitter 100 may include a mechanism that locks transmission of power transmission radio waves when the position of the portable wireless power transmitter 100 is not included in the range of the position set by the position setting unit 114. This mechanism may be, for example, a mechanism that does not accept an operation even if the operation unit 106 is operated, or may be a mechanism that locks power supply from the battery unit 102 to the power transmission unit 108.

[0020] The portable wireless power transmitter 100 may include a frequency selection unit 118. The frequency selection unit 118 selects a frequency band of power transmission radio waves that can be transmitted from the power transmission unit 108 based on a frequency band of power transmission radio waves around the portable wireless power transmitter 100 or a frequency band supported by the power receiver 300. Accordingly, the portable wireless power transmitter 100 transmits radio waves of a specific frequency band among a plurality of frequency bands that can be supported by the power receiver 300. The radio waves of the specific frequency band are, for example, 5.7 GHz band radio waves or 920 MHz band radio waves. Information indicating the frequency band of power transmission radio waves around the portable wireless power transmitter 100 and information indicating the frequency band supported by the power receiver 300 may be obtained by detecting the frequency of radio waves received by a communication circuit built in the portable wireless power transmitter 100, may be obtained from the portable terminal device 200, or may be obtained from the power receiver 300.

[0021] The portable wireless power transmitter 100 may be equipped with a display unit 130 such as an LCD or organic EL display. The display unit 130 displays the power transmission status of the portable wireless power transmitter 100, etc. For example, it may display the irradiation position and angle of the portable wireless power transmitter 100, the power transmission status of the portable wireless power transmitter 100 itself or the surrounding radio wave conditions, and other information related to power transmission. In addition, information transmitted from the power receiver 300 to the power transmission control system 700 may be displayed on the portable wireless power transmitter 100 via the portable terminal device 200 from the power transmission control system 700.

[0022] The power receiver 300 receives power via radio waves transmitted from the portable wireless power transmitter 100 and supplies the received power to the electronic device 400. The power receiver 300 may or may not be connected to the electronic device 400 by a wired connection. If the power receiver 300 is not connected by a wire, it supplies power to the electronic device 400 by transmitting radio waves to the electronic device 400. The power receiver 300 may also have the electronic device 400 built into it. Furthermore, the power receiver 300 may be equipped with a battery or the like for storing the received power.

[0023] As described above, the portable wireless power transmitter 100 incorporates a battery unit 102, a charge / discharge circuit 104, an operation unit 106, a power transmission unit 108, and a control unit 110 into a casing 100A carried by the user. This allows the transmitter to transmit power to a power receiver 300 as desired by the user (worker) by receiving their input. Thus, the portable wireless power transmitter 100 makes it easier to transmit power to a power receiver.

[0024] Furthermore, the portable wireless power transmitter 100 can regulate at least one of the following based on regulatory information: the transmission direction of the power transmission radio waves, the transmission distance, the power transmission, and the transmission frequency. In addition, the portable wireless power transmitter 100 can set the power transmission position based on regulatory information acquired from the portable terminal device 200 and transmit power from the set power transmission position to the power receiver 300. Moreover, the portable wireless power transmitter 100 can set the power transmission position of the portable wireless power transmitter 100 using the angle and distance of the portable terminal device 200 relative to the power receiver 300, as detected by the angle sensor and distance sensor built into the portable terminal device 200. As a result, the portable wireless power transmitter 100 can easily transmit power while complying with legal regulations.

[0025] Furthermore, the portable wireless power transmitter 100 can select a transmission frequency band based on the frequency band of the transmission radio waves in the vicinity of the portable wireless power transmitter 100, or the frequency band supported by the power receiver 300. This allows power transmission to be performed in accordance with the radio wave conditions of the portable wireless power transmitter 100 and the supported frequency band of the power receiver 300, making it easier to transmit power to the power receiver.

[0026] Figure 2 is a block diagram showing another example of the wireless power supply system 1 in the embodiment. The wireless power supply system 1 includes, for example, a portable wireless power transmitter 100, a portable terminal device 200, a power receiver 300, an edge processing unit 310, an antenna unit 420, a plurality of target items 500, an access point 600, a power transmission control system 700, and an inventory management system 710. In this embodiment, the portable wireless power transmitter 100 is connected to the power transmission control system 700 via a portable terminal device 200. However, the embodiment is not limited to this, and the portable wireless power transmitter 100 may have a communication function so that it can communicate with the power transmission control system 700 without going through the portable terminal device 200.

[0027] The power receiver 300 includes, for example, a power receiving unit 302 and a reader / writer 410 wired to the power receiving unit 302. The power receiving unit 302 receives radio waves from the portable wireless power transmitter 100 and supplies power to the reader / writer 410. The reader / writer 410 performs processing for wireless communication, for example, in the UHF (Ultra High Frequency) band. The reader / writer 410 transmits radio waves in the UHF band from the antenna unit 420 and receives UHF band radio waves returned from the UHF tag 502 via the antenna unit 420.

[0028] The edge processing unit 310 is a communication device that is, for example, wired to the power receiver 300 and also communicates with the access point 600. The edge processing unit 310 transmits the information acquired from the reader / writer 410 to the access point 600 via wireless communication.

[0029] The target items 500 are items whose inventory is managed by the inventory management system 710. A UHF tag 502 is attached to each of the target items 500. When the UHF tag 502 receives radio waves from the antenna unit 420, it returns radio waves containing tag information, including the tag ID and information about the target item 500.

[0030] The access point 600 is a communication device that is wirelessly connected to the portable wireless power transmitter 100 and the edge processing unit 310, and communicates with the power transmission control system 700 and the inventory management system 710 via a communication network such as the Internet.

[0031] The power transmission control system 700 includes, for example, a server device for controlling the operation of the access point 600 and the portable wireless power transmitter 100. The power transmission control system 700 communicates with the portable wireless power transmitter 100 and the server device via the access point 600 and controls the power transmission of the portable wireless power transmitter 100. In this embodiment, the access point 600 and the power transmission control system 700 function as a power transmission system that controls the power transmission of the portable wireless power transmitter 100.

[0032] The inventory management system 710 is a server device that manages the inventory of the target items 500. The inventory management system 710 acquires tag information returned by the UHF tag 502 via the power transmission control system 700 and performs management processing such as registering, updating, or deleting the tag information. The inventory management system 710 transmits inventory information based on the tag information to, for example, the terminal device of a user who manages the target items 500. Although this embodiment includes an inventory management system 710, it is merely an example of a system using a portable wireless power transmitter 100, and the inventory management system 710 is not required.

[0033] Figure 3 is a sequence diagram showing an example of the operation procedure of the wireless power supply system 1 in the first embodiment. First, when a user (worker) carrying the portable wireless power transmitter 100 activates the portable wireless power transmitter 100, the communication unit of the portable wireless power transmitter 100 transmits an activation log S100 (step ST100). The activation log S100 is received by the access point 600, and the access point 600 transmits the activation log S100 to the power transmission control system 700. Upon receiving the activation log S100, the power transmission control system 700 performs logging processing, such as storing the activation log S100 in its memory unit (step ST102).

[0034] The portable wireless power transmitter 100 receives user input via the control unit 106 and, by instructing the start of transmission, transmits a power transmission radio wave S102 to the power receiver 300. At this time, the portable wireless power transmitter 100 transmits power to the power receiver 300, which is located in any direction and at any distance pointed towards it by the worker. The power receiver 300 charges itself using the power received from the power transmission radio wave S102 and activates the reader / writer 410 (step ST106). The reader / writer 410 starts reading tag information by transmitting a UHF radio wave S104 to the UHF tag 502, and the UHF tag 502 returns a UHF radio wave S106 containing the tag information to the reader / writer 410 in response to the UHF radio wave S104.

[0035] The edge processing unit 310 transmits the tag information contained in the UHF radio wave S106 to the access point 600 as the reading information S108 of the UHF tag 502. The access point 600 transmits the information S108 obtained from the edge processing unit 310 to the power transmission control system 700 as the reading information S110 of the UHF tag 502.

[0036] The power transmission control system 700 outputs information S110 to the inventory management system 710, and the inventory management system 710 registers the tag information (step ST108). The inventory management system 710 transmits data update information S112 to the access point 600 via the power transmission control system 700 in response to the update of the tag information, and the access point 600 transmits the data update information S112 to the portable wireless power transmitter 100.

[0037] After receiving data update information S112, the portable wireless power transmitter 100 accepts user input via the operation unit 106 and is instructed to stop transmission (step ST110). This stops the power transmission from the portable wireless power transmitter 100 to the power receiver 300.

[0038] As described above, the portable wireless power transmitter 100 transmits a startup log to the power transmission control system 700 when the portable wireless power transmitter 100 is started up, and can receive coordination information from the power transmission control system 700 based on the operation of the electronic device 400 connected to the power receiver 300. The coordination information in this embodiment is tag information returned by the UHF tag 502, but is not limited to this, and can be any information generated by the operation of the electronic device 400.

[0039] Furthermore, the portable wireless power transmitter 100 can start transmitting a power transmission radio wave in response to receiving a start operation after sending a startup log, and stop transmitting a power transmission radio wave in response to receiving a stop operation after receiving tag information (cooperation information). As a result, the portable wireless power transmitter 100 can stop transmitting power after confirming that the power receiver 300 and the electronic device 400 have responded to the power transmission.

[0040] The functions of the portable wireless power transmitter 100 in the above-described embodiment may be implemented using a computer. In that case, the functions may be implemented by recording a program for implementing these functions on a computer-readable recording medium, loading the program recorded on this recording medium into a computer system, and executing it. Here, "computer system" includes hardware such as an OS and peripheral devices. Furthermore, "computer-readable recording medium" refers to portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and storage devices such as hard disks built into a computer system. Moreover, "computer-readable recording medium" may also include those that dynamically hold programs for a short period of time, such as communication lines used when transmitting programs via networks such as the Internet or communication lines such as telephone lines, and those that hold programs for a certain period of time, such as volatile memory inside a computer system that acts as a server or client in such cases. Furthermore, the above-mentioned program may be for implementing a part of the functions described above, or it may be a program that can implement the above-mentioned functions in combination with a program already recorded in the computer system, or it may be implemented using a programmable logic device such as an FPGA (Field Programmable Gate Array).

[0041] Although various embodiments and variations have been described, these are merely examples and are not limited to these. For example, one embodiment or variation, or a part of one embodiment or variation, may be combined with one or more other embodiments or variations to realize one aspect of the present invention. [Explanation of symbols]

[0042] 1. Wireless power supply system 100 Portable Wireless Power Transmitters 100A enclosure 102 Battery section 104 Charge / discharge circuit 106 Operation section 106a Operation Buttons 108 Power Transmission Section 110 Control Unit 112 Acquisition Department 114 Position setting section 116 Presentation section 118 Frequency Selection Section 120 Storage section 130 Display section 200 Portable terminal devices 300 Power receiver 302 Power receiving section 310 Edge Processing Unit 400 Electronic equipment 410 Reader / Writer 420 Antenna section 500 items 502 UHF tag 600 access points 700 Power transmission control system 710 Inventory Management System

Claims

1. A portable wireless power transmitter equipped with a casing that can be carried by the user, which wirelessly supplies power to a power receiver, Inside the aforementioned housing, A battery unit that stores power, A charge / discharge circuit that supplies charging power to the battery section and extracts discharge power from the battery section, An operating unit that receives user input, A power transmission unit that transmits power transmission radio waves using power supplied from the battery unit, A control unit controls the charging and discharging circuit to extract discharge power from the battery unit and supply it to the power transmission unit based on an operation received by the operation unit, A portable wireless power transmitter equipped with [feature / feature].

2. The portable wireless power transmitter according to claim 1, wherein the control unit controls the power transmission unit to regulate at least one of the transmission direction, transmission distance, transmission power, and transmission frequency of the power transmission radio waves transmitted to the power receiver based on the regulation information stored in the memory unit.

3. The system includes an acquisition unit that establishes a communication connection with a portable terminal device carried by a user, and acquires the regulatory information from the portable terminal device and stores it in the storage unit. A position setting unit sets the power transmission position of the device based on the regulatory information acquired by the acquisition unit, A display unit that displays the power transmission position set by the position setting unit, A portable wireless power transmitter according to claim 2, comprising the following:

4. The portable wireless power transmitter according to claim 3, wherein the position setting unit sets the power transmission position of the device using the angle and distance of the portable terminal device relative to the power receiver detected by the angle sensor and distance sensor provided in the portable terminal device.

5. The portable wireless power transmitter according to claim 1, further comprising a frequency selection unit that selects a frequency band of power transmission radio waves that can be transmitted from the power transmission unit based on the frequency band of power transmission radio waves in the vicinity of the device or the frequency band to which the power receiver corresponds.

6. The device includes a communication unit that transmits a startup log to the power transmission control system in response to its own startup, and receives coordination information from the power transmission control system based on the operation of electronic equipment connected to the power receiver. The control unit, After the communication unit transmits the startup log, the operation unit receives a start operation and controls the power transmission unit to start transmitting the power transmission radio waves. After the communication unit receives the communication information, the operation unit receives a stop operation, and in response, the power transmission unit is controlled to stop transmitting the power transmission radio waves. The portable wireless power transmitter according to claim 1.

7. A portable wireless power transmitter comprising a casing carried by a user and wirelessly supplying power to a power receiver, wherein the casing includes: a battery unit for storing power; a charge / discharge circuit for supplying charging power to the battery unit and for extracting discharge power from the battery unit; an operation unit for receiving user input; a power transmission unit for transmitting power signals using power supplied from the battery unit; a control unit for controlling the charge / discharge circuit to extract discharge power from the battery unit and supply it to the power transmission unit based on the operation received by the operation unit; and a communication unit for transmitting a startup log to a power transmission control system when the device is started and receiving coordination information from the power transmission control system based on the operation of electronic equipment connected to the power receiver. A power transmission control system that receives the startup log from the portable wireless power transmitter and transmits coordination information based on the operation of the electronic device from the electronic device connected to the power receiver to the portable wireless power transmitter, A power receiver that receives radio waves transmitted from the aforementioned portable wireless power transmitter, An electronic device that operates using power supplied from the aforementioned power receiver and transmits the aforementioned cooperation information to the power transmission control system, A wireless power transmission system equipped with the following features.

8. The portable wireless power transmitter starts up and sends a startup log to the power transmission control system, The portable wireless power transmitter starts transmitting a power transmission radio wave to the power receiver, The steps include: operating an electronic device using power supplied from the power receiver and transmitting coordinated information to the power transmission control system; The power transmission control system includes the step of transmitting the coordination information to the portable wireless power transmitter, The portable wireless power transmitter stops transmitting the power transmission radio waves in response to receiving the communication information, A wireless power transmission method including

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