WO2022114615A1

WO2022114615A1 - Power transmitting device, and method for tracking maximum efficiency operating point of system comprising same power transmitting device and power receiving device

Info

Publication number: WO2022114615A1
Application number: PCT/KR2021/016369
Authority: WO
Inventors: 김도현; 조치현; 최영복
Original assignee: 삼성전자 주식회사
Priority date: 2020-11-25
Filing date: 2021-11-10
Publication date: 2022-06-02
Also published as: KR20220072611A

Abstract

A power transmitting device may be disclosed. The power transmitting device may comprise: a power supply unit; a converter; an inverter; a transmitting coil; and a control unit. The control unit may be configured to obtain a rectified voltage transferred from a rectifier to a regulator, change a first parameter from among a plurality of parameters related to power transmission of the transmitting coil, determine whether a difference value between the rectified voltage and a target rectified voltage is equal to or greater than a threshold value, adjust a second parameter from among the plurality of parameters on the basis of a change in the first parameter so that the rectified voltage is maintained when the difference value is equal to or greater than the threshold value, calculate power transmission efficiency of a system after the first parameter and the second parameter have changed, maintain a change direction of the first parameter when the power transmission efficiency increases, set the change direction of the first parameter to be reversed when the power transmission efficiency decreases, and track a maximum efficiency operating point at which the power transmission efficiency of the system is maximized by changing the first parameter every first period. Various other embodiments identified by the specification are possible.

Description

Power transmission device and method for tracking maximum efficiency operating point of a system including the power transmission device and the power reception device

Various embodiments disclosed in this document relate to a power transmitting apparatus, and a method for tracking a maximum efficiency operating point of a system including the power transmitting apparatus and the power receiving apparatus.

A power transmitting device such as a power supply device or a charging device may wirelessly transmit power to a power receiving device such as a portable electronic device or a wearable electronic device. A portable electronic device or a wearable electronic device may be charged wirelessly.

Meanwhile, wireless power transmission efficiency may be affected by various factors such as load impedance, operating frequency, and/or transmission distance. In order to increase the wireless power transmission efficiency, the minimum power input point can be tracked while changing the inverter voltage output of the power transmitting device. An optimal load impedance may be tracked using a change in the input impedance of the converter of the power receiving device.

Even if the inverter voltage output of the power transmitting device is changed, it may not be easy to track the optimum impedance by adjusting the output voltage of the rectifier of the power receiving device.

In addition, when the method of tracking the optimal impedance while maintaining a constant output voltage using a switch at the input terminal of the rectifier is applied, the communication method for switching the switch connected to the rectifier and the communication method between the power transmitter and the power receiver are different. may be duplicated. When the communication methods overlap, it may not be easy to apply the switching for adjusting the output voltage of the rectifier to the rectifier because it collides with a load modulation operation of in-band communication.

Also, the operating point at which the efficiency of the power transmitting apparatus is maximized may be different from the operating point at which the efficiency of the entire system including the power transmitting apparatus and the power receiving apparatus is maximized.

Various embodiments disclosed in this document provide a method and system for increasing power transmission efficiency of a system by tracking maximum efficiency point tracking (MEPT) of a system while maintaining a rectified voltage of a power receiving device want to

A power transmission apparatus according to an embodiment disclosed in this document may include a power supply unit, a converter, an inverter, a transmission coil, and a control unit. The control unit obtains a rectified voltage transferred from the rectifier to the regulator, changes a first parameter among a plurality of parameters related to power transmission of the transmitting coil, and the difference value between the rectified voltage and the target rectified voltage is check whether it is equal to or greater than a threshold value, and if the difference value is equal to or greater than the threshold value, adjust a second parameter among the plurality of parameters based on a change in the first parameter so that the rectified voltage is maintained, and the first parameter and calculating the power transmission efficiency of the system after the second parameter is changed, maintaining the change direction of the first parameter when the power transmission efficiency increases, and changing the direction of the first parameter when the power transmission efficiency decreases may be set to be reversed, and the first parameter may be changed every first period to track a maximum efficiency operating point at which the power transmission efficiency of the system is maximized.

In addition, the maximum efficiency operating point tracking method of a system including a power transmitting device and a power receiving device according to an embodiment of the present disclosure includes an operation of obtaining a rectified voltage transmitted from a rectifier to a regulator, the rectified voltage and a target Checking whether the difference value between the rectified voltages is equal to or greater than a threshold value, when the difference value is equal to or greater than the threshold value, changing a first parameter among a plurality of parameters related to power transmission of a transmitting coil, the rectified voltage is adjusting a second parameter of the plurality of parameters based on a change in the first parameter to be maintained, calculating the power transmission efficiency of the system after the first parameter and the second parameter change; Maintaining the change direction of the first parameter when the power transmission efficiency increases, and reversely setting the change direction of the first parameter when the power transmission efficiency decreases, and changing the first parameter every first period and tracking a maximum efficiency operating point at which the power transmission efficiency of the system is maximized.

According to the embodiments disclosed in this document, when the power transmitting device transmits power to the power receiving device having a predetermined impedance at the input terminal of the rectifier under the condition of maintaining a specific rectifier circuit output voltage, the power transmitting device and the power receiving device are The maximum efficiency operating point at which the power transmission efficiency of the including system is maximized may be tracked.

In addition, according to the embodiments disclosed in this document, it is possible to track the maximum efficiency operating point of the system without adding a separate component to the power receiving device.

In addition, according to the embodiments disclosed in this document, it is possible to increase the wireless power transmission efficiency of the entire system including the power transmitting apparatus and the power receiving apparatus.

In addition, various effects directly or indirectly identified through this document may be provided.

1 is a block diagram of an electronic device in a network environment according to various embodiments of the present disclosure;

2 is a block diagram of a power management module and a battery according to various embodiments of the present disclosure;

3 is a block diagram illustrating a system including a power transmitter and a power receiver according to an embodiment.

4 is a flowchart illustrating a method for tracking a maximum efficiency operating point using a system according to an embodiment.

5 is a flowchart illustrating a method for tracking a maximum efficiency operating point using a system according to an embodiment.

6 is a flowchart illustrating a method for tracking a maximum efficiency operating point using a system according to an exemplary embodiment.

7 is a graph showing constant maintenance of an inverter voltage variation according to a comparative example.

8 is a graph illustrating adjustment of an inverter voltage change amount based on system efficiency according to an exemplary embodiment.

9 is a graph illustrating adjusting the maximum efficiency operating point tracking period based on the efficiency of the system according to an exemplary embodiment.

10 is a graph illustrating adjustment of an inverter voltage change amount and a maximum efficiency operating point tracking period based on system efficiency according to an exemplary embodiment.

In connection with the description of the drawings, the same or similar reference numerals may be used for the same or similar components.

Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings. However, this is not intended to limit the present invention to specific embodiments, and it should be understood that various modifications, equivalents, and/or alternatives of the embodiments of the present invention are included.

1 is a block diagram of an electronic device 101 in a network environment 100 according to various embodiments. Referring to FIG. 1 , in a network environment 100 , an electronic device 101 communicates with an electronic device 102 through a first network 198 (eg, a short-range wireless communication network) or a second network 199 . It may communicate with the electronic device 104 or the server 108 through (eg, a long-distance wireless communication network). According to an embodiment, the electronic device 101 may communicate with the electronic device 104 through the server 108 . According to an embodiment, the electronic device 101 includes a processor 120 , a memory 130 , an input module 150 , a sound output module 155 , a display module 160 , an audio module 170 , and a sensor module ( 176), interface 177, connection terminal 178, haptic module 179, camera module 180, power management module 188, battery 189, communication module 190, subscriber identification module 196 , or an antenna module 197 may be included. In some embodiments, at least one of these components (eg, the connection terminal 178 ) may be omitted or one or more other components may be added to the electronic device 101 . In some embodiments, some of these components (eg, sensor module 176 , camera module 180 , or antenna module 197 ) are integrated into one component (eg, display module 160 ). can be

The processor 120, for example, executes software (eg, a program 140) to execute at least one other component (eg, a hardware or software component) of the electronic device 101 connected to the processor 120 . It can control and perform various data processing or operations. According to one embodiment, as at least part of data processing or operation, the processor 120 converts commands or data received from other components (eg, the sensor module 176 or the communication module 190 ) to the volatile memory 132 . may be stored in the volatile memory 132 , and may process commands or data stored in the volatile memory 132 , and store the result data in the non-volatile memory 134 . According to an embodiment, the processor 120 is the main processor 121 (eg, a central processing unit or an application processor) or a secondary processor 123 (eg, a graphic processing unit, a neural network processing unit) a neural processing unit (NPU), an image signal processor, a sensor hub processor, or a communication processor). For example, when the electronic device 101 includes the main processor 121 and the sub-processor 123 , the sub-processor 123 may use less power than the main processor 121 or may be set to be specialized for a specified function. can The auxiliary processor 123 may be implemented separately from or as a part of the main processor 121 .

The auxiliary processor 123 is, for example, on behalf of the main processor 121 while the main processor 121 is in an inactive (eg, sleep) state, or the main processor 121 is active (eg, executing an application). ), together with the main processor 121, at least one of the components of the electronic device 101 (eg, the display module 160, the sensor module 176, or the communication module 190) It is possible to control at least some of the related functions or states. According to an embodiment, the co-processor 123 (eg, an image signal processor or a communication processor) may be implemented as part of another functionally related component (eg, the camera module 180 or the communication module 190). have. According to an embodiment, the auxiliary processor 123 (eg, a neural network processing device) may include a hardware structure specialized for processing an artificial intelligence model. Artificial intelligence models can be created through machine learning. Such learning may be performed, for example, in the electronic device 101 itself on which artificial intelligence is performed, or may be performed through a separate server (eg, the server 108). The learning algorithm may include, for example, supervised learning, unsupervised learning, semi-supervised learning, or reinforcement learning, but in the above example not limited The artificial intelligence model may include a plurality of artificial neural network layers. Artificial neural networks include deep neural networks (DNNs), convolutional neural networks (CNNs), recurrent neural networks (RNNs), restricted boltzmann machines (RBMs), deep belief networks (DBNs), bidirectional recurrent deep neural networks (BRDNNs), It may be one of deep Q-networks or a combination of two or more of the above, but is not limited to the above example. The artificial intelligence model may include, in addition to, or alternatively, a software structure in addition to the hardware structure.

The memory 130 may store various data used by at least one component of the electronic device 101 (eg, the processor 120 or the sensor module 176 ). The data may include, for example, input data or output data for software (eg, the program 140 ) and instructions related thereto. The memory 130 may include a volatile memory 132 or a non-volatile memory 134 .

The program 140 may be stored as software in the memory 130 , and may include, for example, an operating system 142 , middleware 144 , or an application 146 .

The input module 150 may receive a command or data to be used in a component (eg, the processor 120 ) of the electronic device 101 from the outside (eg, a user) of the electronic device 101 . The input module 150 may include, for example, a microphone, a mouse, a keyboard, a key (eg, a button), or a digital pen (eg, a stylus pen).

The sound output module 155 may output a sound signal to the outside of the electronic device 101 . The sound output module 155 may include, for example, a speaker or a receiver. The speaker can be used for general purposes such as multimedia playback or recording playback. The receiver may be used to receive an incoming call. According to one embodiment, the receiver may be implemented separately from or as part of the speaker.

The display module 160 may visually provide information to the outside (eg, a user) of the electronic device 101 . The display module 160 may include, for example, a control circuit for controlling a display, a hologram device, or a projector and a corresponding device. According to an embodiment, the display module 160 may include a touch sensor configured to sense a touch or a pressure sensor configured to measure the intensity of a force generated by the touch.

The audio module 170 may convert a sound into an electric signal or, conversely, convert an electric signal into a sound. According to an embodiment, the audio module 170 acquires a sound through the input module 150 , or an external electronic device (eg, a sound output module 155 ) connected directly or wirelessly with the electronic device 101 . A sound may be output through the electronic device 102 (eg, a speaker or headphones).

The sensor module 176 detects an operating state (eg, power or temperature) of the electronic device 101 or an external environmental state (eg, user state), and generates an electrical signal or data value corresponding to the sensed state. can do. According to an embodiment, the sensor module 176 may include, for example, a gesture sensor, a gyro sensor, a barometric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an IR (infrared) sensor, a biometric sensor, It may include a temperature sensor, a humidity sensor, or an illuminance sensor.

The interface 177 may support one or more designated protocols that may be used by the electronic device 101 to directly or wirelessly connect with an external electronic device (eg, the electronic device 102 ). According to an embodiment, the interface 177 may include, for example, a high definition multimedia interface (HDMI), a universal serial bus (USB) interface, an SD card interface, or an audio interface.

The connection terminal 178 may include a connector through which the electronic device 101 can be physically connected to an external electronic device (eg, the electronic device 102 ). According to an embodiment, the connection terminal 178 may include, for example, an HDMI connector, a USB connector, an SD card connector, or an audio connector (eg, a headphone connector).

The haptic module 179 may convert an electrical signal into a mechanical stimulus (eg, vibration or movement) or an electrical stimulus that the user can perceive through tactile or kinesthetic sense. According to an embodiment, the haptic module 179 may include, for example, a motor, a piezoelectric element, or an electrical stimulation device.

The camera module 180 may capture still images and moving images. According to an embodiment, the camera module 180 may include one or more lenses, image sensors, image signal processors, or flashes.

The power management module 188 may manage power supplied to the electronic device 101 . According to an embodiment, the power management module 188 may be implemented as, for example, at least a part of a power management integrated circuit (PMIC).

The battery 189 may supply power to at least one component of the electronic device 101 . According to one embodiment, battery 189 may include, for example, a non-rechargeable primary cell, a rechargeable secondary cell, or a fuel cell.

The communication module 190 is a direct (eg, wired) communication channel or a wireless communication channel between the electronic device 101 and an external electronic device (eg, the electronic device 102, the electronic device 104, or the server 108). It can support establishment and communication performance through the established communication channel. The communication module 190 may include one or more communication processors that operate independently of the processor 120 (eg, an application processor) and support direct (eg, wired) communication or wireless communication. According to one embodiment, the communication module 190 is a wireless communication module 192 (eg, a cellular communication module, a short-range wireless communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module 194 (eg, : It may include a LAN (local area network) communication module, or a power line communication module). A corresponding communication module among these communication modules is a first network 198 (eg, a short-range communication network such as Bluetooth, wireless fidelity (WiFi) direct, or infrared data association (IrDA)) or a second network 199 (eg, legacy It may communicate with the external electronic device 104 through a cellular network, a 5G network, a next-generation communication network, the Internet, or a computer network (eg, a telecommunication network such as a LAN or a WAN). These various types of communication modules may be integrated into one component (eg, a single chip) or may be implemented as a plurality of components (eg, multiple chips) separate from each other. The wireless communication module 192 uses the subscriber information (eg, International Mobile Subscriber Identifier (IMSI)) stored in the subscriber identification module 196 within a communication network such as the first network 198 or the second network 199 . The electronic device 101 may be identified or authenticated.

The wireless communication module 192 may support a 5G network after a 4G network and a next-generation communication technology, for example, a new radio access technology (NR). NR access technology includes high-speed transmission of high-capacity data (eMBB (enhanced mobile broadband)), minimization of terminal power and access to multiple terminals (mMTC (massive machine type communications)), or high reliability and low latency (URLLC (ultra-reliable and low-latency) -latency communications)). The wireless communication module 192 may support a high frequency band (eg, mmWave band) to achieve a high data rate, for example. The wireless communication module 192 includes various technologies for securing performance in a high-frequency band, for example, beamforming, massive multiple-input and multiple-output (MIMO), all-dimensional multiplexing. It may support technologies such as full dimensional MIMO (FD-MIMO), an array antenna, analog beam-forming, or a large scale antenna. The wireless communication module 192 may support various requirements specified in the electronic device 101 , an external electronic device (eg, the electronic device 104 ), or a network system (eg, the second network 199 ). According to an embodiment, the wireless communication module 192 may include a peak data rate (eg, 20 Gbps or more) for realizing eMBB, loss coverage (eg, 164 dB or less) for realizing mMTC, or U-plane latency for realizing URLLC ( Example: downlink (DL) and uplink (UL) each 0.5 ms or less, or round trip 1 ms or less).

The antenna module 197 may transmit or receive a signal or power to the outside (eg, an external electronic device). According to an embodiment, the antenna module 197 may include an antenna including a conductor formed on a substrate (eg, a PCB) or a radiator formed of a conductive pattern. According to an embodiment, the antenna module 197 may include a plurality of antennas (eg, an array antenna). In this case, at least one antenna suitable for a communication method used in a communication network such as the first network 198 or the second network 199 is connected from the plurality of antennas by, for example, the communication module 190 . can be selected. A signal or power may be transmitted or received between the communication module 190 and an external electronic device through the selected at least one antenna. According to some embodiments, other components (eg, a radio frequency integrated circuit (RFIC)) other than the radiator may be additionally formed as a part of the antenna module 197 .

According to various embodiments, the antenna module 197 may form a mmWave antenna module. According to one embodiment, the mmWave antenna module comprises a printed circuit board, an RFIC disposed on or adjacent to a first side (eg, bottom side) of the printed circuit board and capable of supporting a designated high frequency band (eg, mmWave band); and a plurality of antennas (eg, an array antenna) disposed on or adjacent to a second side (eg, top or side) of the printed circuit board and capable of transmitting or receiving signals of the designated high frequency band. can do.

At least some of the components are connected to each other through a communication method between peripheral devices (eg, a bus, general purpose input and output (GPIO), serial peripheral interface (SPI), or mobile industry processor interface (MIPI)) and a signal ( eg commands or data) can be exchanged with each other.

According to an embodiment, the command or data may be transmitted or received between the electronic device 101 and the external electronic device 104 through the server 108 connected to the second network 199 . Each of the external

electronic devices

102 or 104 may be the same as or different from the electronic device 101 . According to an embodiment, all or a part of operations executed in the electronic device 101 may be executed in one or more external

electronic devices

102 , 104 , or 108 . For example, when the electronic device 101 is to perform a function or service automatically or in response to a request from a user or other device, the electronic device 101 may perform the function or service itself instead of executing the function or service itself. Alternatively or additionally, one or more external electronic devices may be requested to perform at least a part of the function or the service. One or more external electronic devices that have received the request may execute at least a part of the requested function or service, or an additional function or service related to the request, and transmit a result of the execution to the electronic device 101 . The electronic device 101 may process the result as it is or additionally and provide it as at least a part of a response to the request. For this, for example, cloud computing, distributed computing, mobile edge computing (MEC), or client-server computing technology may be used. The electronic device 101 may provide an ultra-low latency service using, for example, distributed computing or mobile edge computing. In another embodiment, the external electronic device 104 may include an Internet of things (IoT) device. Server 108 may be an intelligent server using machine learning and/or neural networks. According to an embodiment, the external electronic device 104 or the server 108 may be included in the second network 199 . The electronic device 101 may be applied to an intelligent service (eg, smart home, smart city, smart car, or health care) based on 5G communication technology and IoT-related technology.

2 is a block diagram 200 of a power management module 188 and a battery 189, in accordance with various embodiments. Referring to FIG. 2 , the power management module 188 may include a charging circuit 210 , a power regulator 220 , or a power gauge 230 . The charging circuit 210 may charge the battery 189 using power supplied from an external power source for the electronic device 101 . According to an embodiment, the charging circuit 210 may include a type of external power source (eg, a power adapter, USB or wireless charging), a size of power that can be supplied from the external power source (eg, about 20 watts or more), or a battery 189 ), a charging method (eg, normal charging or fast charging) may be selected based on at least some of the properties, and the battery 189 may be charged using the selected charging method. The external power source may be connected to the electronic device 101 by wire through, for example, the connection terminal 178 or wirelessly through the antenna module 197 .

The power regulator 220 may generate a plurality of powers having different voltages or different current levels by, for example, adjusting a voltage level or a current level of power supplied from an external power source or battery 189 . The power regulator 220 may adjust the external power source or the power of the battery 189 to a voltage or current level suitable for each of some of the components included in the electronic device 101 . According to an embodiment, the power regulator 220 may be implemented in the form of a low drop out (LDO) regulator or a switching regulator. The power gauge 230 may measure usage state information about the battery 189 (eg, the capacity of the battery 189 , the number of times of charging and discharging, a voltage, or a temperature).

The power management module 188 may, for example, use the charging circuit 210 , the voltage regulator 220 , or the power gauge 230 , to control the battery 189 based at least in part on the measured usage state information. It is possible to determine charge-related state of charge information (eg, lifespan, overvoltage, undervoltage, overcurrent, overcharge, overdischarge, overheating, short circuit, or swelling). The power management module 188 may determine whether the battery 189 is normal or abnormal based at least in part on the determined state of charge information. When it is determined that the state of the battery 189 is abnormal, the power management module 188 may adjust charging of the battery 189 (eg, decrease charging current or voltage, or stop charging). According to an embodiment, at least some of the functions of the power management module 188 may be performed by an external control device (eg, the processor 120 ).

The battery 189 may include a battery protection circuit module (PCM) 240 , according to one embodiment. The battery protection circuit 240 may perform one or more of various functions (eg, a pre-blocking function) to prevent deterioration or burnout of the battery 189 . The battery protection circuit 240 is additionally or alternatively, a battery management system (battery management system) capable of performing various functions including cell balancing, capacity measurement of the battery, number of times of charge/discharge measurement, temperature measurement, or voltage measurement. BMS))).

According to an embodiment, at least a portion of the use state information or the charge state information of the battery 189 is a corresponding sensor (eg, a temperature sensor), a power gauge 230 , or a power management module among the sensor modules 276 . (188) can be used. According to an embodiment, the corresponding sensor (eg, a temperature sensor) of the sensor module 176 is included as a part of the battery protection circuit 140 , or is a separate device to be disposed near the battery 189 . can

3 is a block diagram illustrating a system 300 including a power transmission device 310 and a power reception device 320 according to an embodiment. 3 illustrates a case in which power is transmitted in an inductive manner. However, the present invention is not limited thereto, and the system 300 according to the present invention may be applied even when power is transmitted in a resonance manner.

In an embodiment, the power transmission device 310 may be a power supply device or a charging device. The power receiving device 320 may be a portable electronic device or a wearable electronic device. The power transmitter 310 may wirelessly transmit power to the power receiver 320 . The power receiving device 320 may be wirelessly charged by the power transmitting device 310 . In an embodiment, the power transmitting device 310 may be a portable electronic device or a wearable electronic device similar to the power receiving device 320 .

In an embodiment, the power transmission device 310 includes a power supply unit 311 , a converter 312 , an inverter 313 , a first matching unit 314 , a transmission coil 315 , It may include a control unit 316 , and a first communication circuit 317 .

In an embodiment, the power supply unit 311 may receive power from the outside. The power supply unit 311 may transfer the input voltage Vin and the input current Iin to the converter 312 .

In an embodiment, the converter 312 may receive the input voltage Vin and the input current Iin from the power source 311 . The converter 312 may generate an inverter voltage Vinv and an inverter current Iinv based on the input voltage Vin and the input current Iin. The converter 312 may transmit the inverter voltage Vinv and the inverter current Iinv to the inverter 313 . The converter 312 may be a DC-DC converter.

In an embodiment, the inverter 313 may receive the inverter voltage Vinv and the inverter current Iinv from the converter 312 . The inverter 313 may invert the inverter voltage Vinv and the inverter current Iinv to transmit the inverted value to the first matching unit 314 . The inverter 313 may further include a power amplifier (PA) or be replaced with a power amplifier.

In an embodiment, the first matching unit 314 may receive the inverter voltage Vinv and the inverter current Iinv from the inverter 313 . The inverter 313 may output an inverter voltage Vinv and an inverter current Iinv converted into alternating current (AC). The first matching unit 314 may transfer the inverter voltage Vinv and the inverter current Iinv converted into alternating current (AC) to the transmitting coil 315 . The first matching unit 314 may compensate or adjust the input impedance of the transmitting end of the transmitting coil 315 . The first matching unit 314 may be an impedance matching network (IMN).

In an embodiment, the transmitting coil 315 may receive an inverted inverter voltage Vinv and an inverter current Iinv from the first matching unit 314 . The transmitting coil 315 may wirelessly transmit power based on the inverted inverter voltage Vinv and the inverter current Iinv.

In an embodiment, the controller 316 may control the duty of the converter 312 . The duty may mean a ratio of a length of time turned on during a switching operation for controlling turn-on and turn-off of the converter 312 during a specified time period. . By changing the duty, it is possible to control the magnitude of the inverter voltage Vinv or the ratio of the magnitude of the inverter voltage Vinv compared to the input voltage Vin. Duty may be referred to as a duty cycle (cycle) or a duty ratio (ratio). The controller 316 may control the frequency of the inverter 313 . The frequency of the inverter 313 may be the operating frequency of the power transmission device 310 . By changing the operating frequency, the input impedance of the system 300 may be changed. Accordingly, the inverter current Iinv output from the inverter 313 and the inverter power Pinv output from the inverter 313 may be controlled by changing the operating frequency. The controller 316 may be a microprocessor.

In an embodiment, the first communication circuit 317 may perform wireless communication with the second communication circuit 325 of the power receiving device 320 . The first communication circuit 317 may receive information related to the charging state of the power receiving device 320 . The first communication circuit 317 may receive information related to voltage, current, and/or power of the power receiving device 320 . The first communication circuit 317 may transmit information related to the voltage, current, and/or power of the power receiving device 320 to the controller 316 .

In an embodiment, the power receiving device 320 includes a receiving coil 321 , a second matching unit 322 , a rectifier 323 , a regulator 324 , a battery 189 , and a second communication unit. It may include a circuit 325 (eg, the wireless communication module 192 of FIG. 1 ), and a sensing circuit 326 .

In an embodiment, the receiving coil 321 may receive power wirelessly transmitted from the transmitting coil 315 . The receiving coil 321 may transmit the received power to the second matching unit 322 .

In an embodiment, the second matching unit 322 may receive power from the receiving coil 321 . The second matching unit 322 may transmit power to the rectifier 323 . The second matching unit 322 may adjust or compensate the input impedance seen from the receiving coil 321 of the power receiving device 320 to the load terminal (eg, the battery 189). The second matching unit 322 may be an impedance matching network.

In an embodiment, the rectifier 323 may receive power from the second matching unit 322 . The rectifier 323 may generate a rectified voltage Vrect and a rectified current Irect based on the received power. The rectifier 323 may transfer the rectified voltage Vrect and the rectified current Irect to the regulator 324 .

In an embodiment, the regulator 324 may receive the rectified voltage Vrect and the rectified current Irect from the rectifier 323 . The regulator 324 may generate the output voltage Vout and the output current Iout based on the received rectified voltage Vrect and the rectified current Irect. The regulator 324 may transfer the output voltage Vout and the output current Iout to the battery 189 to charge the battery 189 . The battery 189 may serve as a load.

In an embodiment, the second communication circuit 325 may receive data regarding the rectified voltage Vrect, the rectified current Irect, the output voltage Vout, and the output current Iout. The second communication circuit 325 may perform wireless communication with the power transmission device 310 .

In an embodiment, the wireless communication performed by the power receiving device 320 and the power transmitting device 310 may be in-band or out of band communication. According to various embodiments, when the power receiving device 320 uses in-band communication, a data signal may be transmitted in a power signal. When the power receiving device 320 uses in-band communication, the second communication circuit 325 uses a frequency that is the same as or adjacent to the frequency used for power transmission by the power transmitting device 310 . to communicate with the power transmitter 310 . For example, among international standards, WPC transmits power using a frequency band of about 100 kHz or more and about 200 kHz or less, and uses a modulation signal of about 1.5 kHz or more and about 2.5 kHz or less to communicate. . Data (or communication signal) generated by the second communication circuit 325 may be transmitted using the receiving coil 321 . The second communication circuit 325 may transmit data to the power transmitter 310 using an amplitude shift keying (ASK) or a frequency shift keying (FSK) modulation technique. For example, in WPC among international standards, data may be transmitted from the power receiving device 320 to the power transmitting device 310 in an ASK method based on load modulation. As another example, the second communication circuit 325 may communicate with the power transmitter 310 by changing the frequency of the power signal transmitted through the receiving coil 321 . Specifically, the second communication circuit 325 may express data by increasing or decreasing the frequency of the power reception signal.

According to various embodiments, when the power receiving device 320 uses out of band communication, the second communication circuit 325 uses a frequency used for power transmission by the power transmitting device 310 . It is possible to communicate with the first communication circuit 317 of the power transmission device 310 using a frequency different from . For example, the communication circuit 325 uses any one of various short-distance communication methods such as Bluetooth (Bluetooth), Bluetooth low energy (BLE), Wi-Fi, and/or near field communication (NFC) for the first communication Information related to the state of charge to the circuit 317 (eg, voltage value after rectifier, rectified voltage value (eg, Vrect) information, current information flowing from the receiving coil 321 or the rectifier 323 , various packets, and/or message) can be obtained. The second communication circuit 325 may transmit data regarding the rectified voltage Vrect, the rectified current Irect, the output voltage Vout, and the output current Iout to the first communication circuit 317 through wireless communication. have.

In an embodiment, the sensing circuit 326 includes an input voltage Vin, an input current Iin, an inverter voltage Vinv, an inverter current Iinv, a rectified voltage Vrect, a rectified current Irect, and an output voltage ( Vout), and the output current Iout can be sensed. The sensing circuit 326 may transmit the sensed input voltage Vin and input current Iin to the controller 316 or a micro controller unit (MCU).

In an embodiment, the control unit 316 or the MCU receiving the input voltage Vin and the input current Iin may calculate the transmission power of the power transmission device 310 . For example, the controller 316 or the MCU may calculate the transmit power of the power transmitter 310 by multiplying the value of the input voltage Vin and the value of the input current Iin. The sensing circuit 326 may transmit a signal including data regarding the output voltage Vout and the output current Iout to the controller 316 or the MCU. The controller 316 or the MCU may calculate the received power of the power receiving device 320 by demodulating the signal. The controller 316 or the MCU may measure the power transmission efficiency of the system 300 by calculating a ratio of the transmission power and the reception power.

4 is a flowchart 400 illustrating a method for tracking a maximum efficiency operating point using a system (eg, the system 300 of FIG. 3 ) according to an embodiment.

In operation 410 , the control unit (eg, the control unit 316 of FIG. 3 ) of the system 300 according to an exemplary embodiment transmits a rectified voltage (eg, the power reception device 320 of FIG. 3 ) transmitted from the power receiving device (eg, the power receiving device 320 of FIG. 3 ). : Vrect of FIG. 3) can be obtained. For example, when the power receiving device 320 uses in-band communication, the control unit 316 is a transmitting coil that communicates with a receiving coil (eg, the receiving coil 321 of FIG. 3 ) ( Example: Data regarding the rectified voltage Vrect may be obtained from the transmission coil 315 of FIG. 3 . As another example, when the power receiving device 320 uses out of band communication, the control unit 316 communicates with a second communication circuit (eg, the second communication circuit 325 of FIG. 3 ). Data regarding the rectified voltage Vrect may be obtained from the first communication circuit 317 . Since information of the power receiving device 320 can be known through out-of-band communication, it can be applied even when power is transmitted in a resonance method.

In operation 420 , the controller 316 according to an embodiment may determine whether a difference value between the rectified voltage Vrect and the target rectified voltage is equal to or greater than a threshold value. The controller 316 may check whether a difference value between the obtained rectified voltage Vrect of the power receiver 320 and a target rectified voltage to be output from the power receiver 320 is equal to or greater than a threshold value. When the rectified voltage Vrect differs from the target rectified voltage by more than a threshold value, the controller 316 may determine that the output of the power receiving device 320 is stabilized.

In operation 430 , the controller 316 according to an embodiment may change a first parameter among a plurality of parameters related to power transmission of a transmission coil (eg, the transmission coil 315 of FIG. 3 ). A plurality of parameters related to power transmission may change power transmission efficiency of the transmitting coil 315 . The plurality of parameters related to power transmission may include an inverter voltage (eg, an inverter voltage Vinv of FIG. 3 ), an operating frequency, and a duty cycle.

In operation 440 , the controller 316 according to an embodiment may adjust a second parameter among a plurality of parameters based on a change in the first parameter so that the rectified voltage Vrect is maintained. The rectified voltage Vrect may have a size specified according to a type of a power receiving device (eg, the power receiving device 320 of FIG. 3 ), a rated voltage standard, and/or an international standard for wireless power transmission. For example, the wireless power transmission international standard may be a wireless power consortium (WPC). However, the present invention is not limited thereto, and the international standard for wireless power transmission may be a wireless power transmission scheme for transmitting power while maintaining a constant rectified voltage (Vrect). The controller 316 may adjust the second parameter so that the level of the rectified voltage Vrect is maintained despite the change of the first parameter.

In operation 450 , the controller 316 according to an embodiment may calculate the power transmission efficiency of the system 300 after the first parameter and the second parameter are changed. For example, the controller 316 may calculate the power transmission efficiency based on the transmitted power by changing the first parameter and the second parameter and the rectified voltage Vrect received from the power receiving device.

In operation 460 , the control unit 316 according to an embodiment may maintain a change direction of the first parameter when the power transmission efficiency increases, and reverse the change direction of the first parameter when the power transmission efficiency decreases.

In operation 470 , the controller 316 may change the first parameter every first period to track the maximum efficiency point tracking (MEPT) at which the power transmission efficiency is maximized.

5 is a flowchart 500 illustrating a method for tracking a maximum efficiency operating point using a system (eg, the system 300 of FIG. 3 ) according to an embodiment.

In operation 510 , the control unit (eg, the control unit 316 of FIG. 3 ) of the system 300 according to an embodiment may start with a default inverter voltage value (Start with default Vinv value). The controller 316 may control the inverter (eg, the inverter 313 of FIG. 3 ) to start driving with the initial inverter voltage Vinv.

In operation 520 , the controller 316 according to an embodiment may perform frequency adjustment for target Vrect. The controller 316 may track the operating frequency for the target rectified voltage Vrect through feedback-loop control. When the magnitude of the rectified voltage Vrect increases, the operating frequency may increase.

In operation 530 , the controller 316 according to an embodiment may sense the transmission efficiency. Transmission efficiency may be referred to as rail power (Prail) or received power packet (RPP). When the difference value between the sensed rectified voltage Vrect and the target rectified voltage is less than or equal to a threshold value, the controller 316 may measure and store the efficiency. When the difference value between the sensed rectified voltage Vrect and the target rectified voltage is equal to or greater than the threshold value, the output may be stabilized. When the difference value between the sensed rectified voltage Vrect and the target rectified voltage is less than or equal to a threshold value, a CEP packet related to wireless power transfer data may be less than or equal to a specific value on a wireless power transfer international standard (WPC) system.

In operation 540 , the controller 316 according to an embodiment may change the inverter voltage Vinv by the inverter voltage change amount ΔVinv. The controller 316 may increase or decrease the inverter voltage Vinv by the inverter voltage change amount ΔVinv. The controller 316 may initially increase the inverter voltage Vinv by the inverter voltage change amount ΔVinv.

In operation 550 , the controller 316 according to an embodiment may perform frequency adjustment for target Vrect. The controller 316 may adjust the operating frequency so that the rectified voltage Vrect is constantly maintained even when the inverter voltage Vinv changes by the inverter voltage change amount ΔVinv. 5 illustrates a case in which the first parameter among the plurality of parameters is the inverter voltage Vint and the second parameter is the operating frequency.

The control unit 316 according to an embodiment may detect transmission efficiency in operation 560 .

In operation 570 , the control unit 316 according to an embodiment determines the transmission efficiency Eff_previous before the inverter voltage Vinv changes and the transmission efficiency Eff after the inverter voltage Vinv changes by the inverter voltage change amount ΔVinv. ) can be compared. When the inverter voltage Vinv changes by the inverter voltage change amount ΔVinv, the transmission efficiency Eff is higher than the transmission efficiency Eff_previous before the inverter voltage Vinv changes (operation 570 - Yes) ) may proceed to operation 540 . When the inverter voltage Vinv changes by the inverter voltage change amount ΔVinv, the transmission efficiency Eff is lower than the transmission efficiency Eff_previous before the inverter voltage Vinv changes (operation 570 - No ) may proceed to operation 580 .

The controller 316 according to an embodiment may change the control direction in operation 580 . The controller 316 may add 1 to the value of the factor n that determines the control direction. After changing the factor n that determines the control direction, the controller 316 may proceed to operation 540 .

The control unit 316 according to an embodiment may maintain the change direction of the inverter voltage Vinv when the transmission efficiency Eff increases compared to the conventional one after the inverter voltage Vinv changes by the inverter voltage change amount ΔVinv. . The control unit 316 increases the inverter voltage Vinv by the inverter voltage change amount ΔVinv when the transmission efficiency Eff increases compared to the conventional one after the inverter voltage Vinv changes by the inverter voltage change amount ΔVinv. . The control unit 316 may reverse the change direction of the inverter voltage Vinv when the transmission efficiency Eff decreases compared to the conventional one after the inverter voltage Vinv changes by the inverter voltage change amount ΔVinv. The control unit 316 may reduce the inverter voltage Vinv by the inverter voltage change amount ΔVinv when the transmission efficiency Eff decreases compared to the conventional one after the inverter voltage Vinv changes by the inverter voltage change amount ΔVinv. . The controller 316 may change the inverter voltage Vinv by the inverter voltage change amount ΔVinv every first period to track the maximum efficiency operating point at which the transmission efficiency is maximized.

In an embodiment, the controller 316 may repeatedly perform an operation of changing the inverter voltage Vinv by the inverter voltage change amount ΔVinv every first period. The controller 316 may track the maximum maximum efficiency operating point while performing an operation of changing the inverter voltage Vinv by the inverter voltage change amount ΔVinv for an infinite number of times every first period. For example, when the inverter voltage Vinv at an ideal maximum efficiency operating point is 10.05V, that is, when the inverter voltage Vinv is 10.05V, it may be assumed that the inverter has the maximum efficiency. Also, it may be assumed that the inverter voltage change amount ΔVinv is 0.1V. When the maximum efficiency operating point is tracked while the operation of changing the inverter voltage Vinv by the inverter voltage change amount ΔVinv every first period is performed for an infinite number of times, the inverter voltage Vinv has a value of 10.0V and a value of 10.1V can be repeated indefinitely.

In an embodiment, when a specified condition is satisfied, the controller 316 may end the operation of changing the inverter voltage Vinv by the inverter voltage change amount ΔVinv every first period. The control unit 316 performs an operation of changing the inverter voltage Vinv by the inverter voltage change amount ΔVinv every first period, and when the difference value from the inverter voltage Vinv value at the maximum efficiency operating point is less than a threshold value, the inverter The operation of changing the voltage Vinv may be terminated. For example, in the previous example assuming that the inverter voltage Vinv has the maximum efficiency when the inverter voltage Vinv is 10.05V and the inverter voltage change amount ΔVinv is 0.1V, the inverter voltage Vinv value at the maximum efficiency operating point The threshold value of the difference value can be set to 0.05V. In this case, when the inverter voltage Vinv starts at 9.0V at the initial time point and reaches a value of 10.0V, the operation of changing the inverter voltage Vinv may be terminated. Alternatively, when the inverter voltage Vinv starts at 11.0 V at the initial time point and reaches a value of 10.1 V, the operation of changing the inverter voltage Vinv may be terminated.

In an embodiment, the controller 316 may set the direction in which the inverter voltage Vinv changes according to whether the efficiency is increased for each first cycle. When the efficiency decreases after the inverter voltage Vinv increases by the inverter voltage change amount ΔVinv, the control unit 316 decreases the inverter voltage Vinv by the inverter voltage change amount ΔVinv at the time when the next first cycle elapses. have. When the efficiency increases after the inverter voltage Vinv decreases by the inverter voltage change amount ΔVinv, the controller 316 may decrease the inverter voltage Vinv again when the next first period elapses.

In an embodiment, when the efficiency decreases after the inverter voltage Vinv decreases by the inverter voltage change amount ΔVinv, the controller 316 may increase the inverter voltage Vinv when the next first period elapses. In this case, the inverter voltage Vinv may repeatedly have between two values. In this case, it can be determined that the inverter voltage at the maximum efficiency operating point is between two values. When the control unit 316 tracks the maximum efficiency operating point while performing the operation of changing the inverter voltage Vinv by the inverter voltage change amount ΔVinv every first period for an infinite number of times, the control unit 316 controls the inverter voltage Vinv It is possible to control to have two values interposed between the inverter voltage Vinv at this maximum efficiency operating point while repeating infinitely.

In one embodiment, when the controller 316 ends the operation of changing the inverter voltage Vinv by the inverter voltage change amount ΔVinv every first period when a specified condition is satisfied, the inverter voltage change amount ΔVinv is to be controlled. can Since the control unit 316 knows two values sandwiching the inverter voltage Vinv at the maximum efficiency operating point, it is close to the inverter voltage Vinv at the maximum efficiency operating point while reducing the magnitude of the inverter voltage change amount ΔVinv. value can be tracked.

6 is a flowchart 600 illustrating a method for tracking a maximum efficiency operating point using a system (eg, the system 300 of FIG. 3 ) according to an embodiment.

In operation 610 , the control unit (eg, the control unit 316 of FIG. 3 ) of the system 300 according to an embodiment may start with a reference frequency value (Start with default Freq value). The controller 316 may control the inverter (eg, the inverter 313 of FIG. 3 ) to start driving at the initial driving frequency Freq.

In operation 620 , the controller 316 according to an embodiment may adjust the inverter voltage Vinv for the target rectified voltage (Vinv adjustment for target Vrect). The controller 316 may track the inverter voltage Vinv for the target rectified voltage Vrect through feedback-loop control. When the magnitude of the rectified voltage Vrect increases, the inverter voltage Vinv may increase.

In operation 630 , the controller 316 according to an embodiment may sense a sensing efficiency. Efficiency may be transmission efficiency. Transmission efficiency may be referred to as rail power (Prail) or RPP. When the difference value between the sensed rectified voltage Vrect and the target rectified voltage is less than or equal to a threshold value, the controller 316 may measure and store the efficiency. When the difference value between the sensed rectified voltage Vrect and the target rectified voltage is less than or equal to the threshold value, the output may be stabilized. When the difference value between the sensed rectified voltage Vrect and the target rectified voltage is less than or equal to a threshold value, a CEP packet related to wireless power transfer data may be less than or equal to a specific value on a wireless power transfer international standard (WPC) system.

In operation 640 , the controller 316 according to an embodiment may change the driving frequency Freq by the driving frequency change amount ΔFreq. The controller 316 may increase or decrease the driving frequency Freq by the driving frequency change amount ΔFreq. The controller 316 may initially increase the driving frequency Freq by the driving frequency change amount ΔFreq (n=0).

In operation 650 , the controller 316 according to an embodiment may adjust the inverter voltage Vinv for the target rectified voltage (Vinv adjustment for target Vrect). The controller 316 may adjust the inverter voltage Vinv so that the rectified voltage Vrect is maintained constant even when the driving frequency Freq is changed by the driving frequency change amount ΔFreq. 6 illustrates a case in which a first parameter among a plurality of parameters is an operating frequency and a second parameter is an inverter voltage Vint.

The control unit 316 according to an embodiment may detect the efficiency in operation 660 .

In operation 670 , the control unit 316 according to an embodiment controls the transmission efficiency Eff_previous before the driving frequency Freq is changed and the transmission efficiency Eff after the driving frequency Freq is changed by the driving frequency variation ΔFreq. ) can be compared. When the driving frequency Freq changes by the driving frequency change amount ΔFreq, the transmission efficiency Eff is higher than the transmission efficiency Eff_previous before the driving frequency Freq changes (operation 670 - Yes ) may proceed to operation 640 . When the driving frequency Freq is changed by the driving frequency change amount ΔFreq and the transmission efficiency Eff is lower than the transmission efficiency Eff_previous before the driving frequency Freq is changed (operation 670 - No ) may proceed to operation 680 .

The controller 316 according to an embodiment may change the control direction in operation 680 . The controller 316 may add 1 to the value of the factor n that determines the control direction. After changing the factor n that determines the control direction, the controller 316 may proceed to operation 640 .

The control unit 316 according to an embodiment may maintain the change direction of the driving frequency Freq when the transmission efficiency Eff increases compared to the conventional one after the driving frequency Freq changes by the driving frequency change amount ΔFreq. . The controller 316 may increase the driving frequency change amount ΔFreq by the driving frequency change amount ΔFreq when the transmission efficiency Eff increases compared to the existing one after the driving frequency Freq changes by the driving frequency change amount ΔFreq. The controller 316 may reverse the change direction of the driving frequency Freq when the transmission efficiency Eff is reduced compared to the existing one after the driving frequency Freq is changed by the driving frequency change amount ΔFreq. The control unit 316 may reduce the driving frequency Freq by the driving frequency change amount ΔFreq when the transmission efficiency Eff decreases compared to the conventional one after the driving frequency Freq changes by the driving frequency change amount ΔFreq. . The control unit 316 may change the driving frequency Freq by the driving frequency change amount ΔFreq every first period to track the maximum efficiency operating point at which the transmission efficiency is maximized.

In an embodiment, the controller 316 may repeatedly perform an operation of changing the driving frequency Freq by the driving frequency change amount ΔFreq every first period. The control unit 316 may track the maximum maximum efficiency operating point while performing the operation of changing the driving frequency Freq by the driving frequency change amount ΔFreq for an infinite number of times every first period. For example, when the driving frequency Freq at the ideal maximum efficiency operating point is 150.05 KHz, that is, when the driving frequency Freq is 150.05 KHz, it may be assumed to have the maximum efficiency. Also, it may be assumed that the driving frequency change amount ΔFreq is 0.1 KHz. When the maximum efficiency operating point is tracked while the operation of changing the driving frequency Freq by the driving frequency change amount ΔFreq every first period is performed for an infinite number of times, the driving frequency Freq is a value of 150.0KHz and a value of 150.1KHz can be repeated indefinitely.

In an embodiment, when a specified condition is satisfied, the controller 316 may end the operation of changing the driving frequency Freq by the driving frequency change amount ΔFreq every first period. The control unit 316 performs an operation of changing the driving frequency Freq by the driving frequency change amount ΔFreq every first period, and drives when the difference value from the driving frequency Freq value at the maximum efficiency operating point is less than or equal to a threshold value The operation of changing the frequency Freq may be terminated. For example, in the previous example assuming that the driving frequency Freq is 150.05 KHz, the maximum efficiency is achieved and the driving frequency change amount ΔFreq is 0.1 KHz, the driving frequency Freq value at the maximum efficiency operating point. The threshold value of the difference value can be set to 0.05KHz. In this case, when the driving frequency Freq starts at 140 KHz at the initial time point and reaches a value of 150.0 KHz, the operation of changing the driving frequency Freq may be terminated. Alternatively, when the driving frequency Freq starts at 160 KHz at the initial time point and reaches a value of 150.1 KHz, the operation of changing the driving frequency Freq may be terminated.

In an embodiment, the controller 316 may set the direction in which the driving frequency Freq changes according to whether the efficiency is increased in each first cycle. When the efficiency decreases after the driving frequency Freq increases by the driving frequency change amount ΔFreq, the control unit 316 may decrease the driving frequency Freq by the driving frequency change amount ΔFreq at the time when the next first period elapses. have. When the efficiency increases after the driving frequency Freq decreases by the driving frequency change amount ΔFreq, the controller 316 may decrease the driving frequency Freq again when the next first period elapses.

In an embodiment, when the efficiency decreases after the driving frequency Freq decreases by the driving frequency change amount ΔFreq, the controller 316 may increase the driving frequency Freq when the next first period elapses. In this case, the driving frequency Freq may repeatedly have between two values. In this case, it can be determined that the driving frequency at the maximum efficiency operating point is between two values. When the control unit 316 tracks the maximum efficiency operating point while performing the operation of changing the driving frequency Freq by the driving frequency change amount ΔFreq every first period for an infinite number of times, the control unit 316 controls the driving frequency Freq It is possible to control so that two values with the driving frequency Freq at the maximum efficiency operating point therebetween are repeated infinitely.

In one embodiment, when the control unit 316 ends the operation of changing the driving frequency Freq by the driving frequency change amount ΔFreq every first period when the specified condition is satisfied, the driving frequency change amount ΔFreq is to be controlled. can Since the control unit 316 knows two values interposed between the driving frequency Freq at the maximum efficiency operating point, the control unit 316 is close to the driving frequency Freq at the maximum efficiency operating point while reducing the magnitude of the driving frequency change ΔFreq. value can be tracked.

7 is a graph 700 illustrating that an inverter voltage change amount (eg, an inverter voltage change amount ΔVinv of FIG. 5 ) is constantly maintained according to a comparative example.

In a comparative example, the first graph 710 may represent an inverter voltage Vinv(V) over time. The inverter voltage Vinv(V) may change by the inverter voltage change amount ΔVinv having a constant magnitude for each first period.

In a comparative example, the second graph 720 may represent the power transmission efficiency (%) of a system (eg, the system 300 of FIG. 3 ) over time. The power transfer efficiency (%) of the system 300 may have a maximum efficiency operating point 730 . The first voltage level 711 that is the magnitude of the inverter voltage Vinv(V) at the maximum efficiency operating point 730 may be calculated.

In the comparative example, when the inverter voltage Vinv(V) is changed by the inverter voltage change amount ΔVinv having a constant magnitude for each first cycle, the number of changes and the time it takes to track the maximum efficiency operating point 730 may increase. can For example, when the inverter voltage (Vinv(V)) is changed by the inverter voltage change amount (ΔVinv), which is a constant magnitude for each first cycle, the maximum efficiency operating point 730 can be tracked through 15 iteration changes. have.

8 is a graph 800 illustrating adjustment of an inverter voltage change amount ΔVinv based on the efficiency of a system (eg, the system 300 of FIG. 3 ) according to an exemplary embodiment.

In an embodiment, the first graph 810 may represent an inverter voltage Vinv(V) over time. The inverter voltage Vinv(V) may change by the inverter voltage change amount ΔVinv for each first period.

In an embodiment, the second graph 820 may represent the power transmission efficiency (%) of a system (eg, the system 300 of FIG. 3 ) over time. The power transfer efficiency (%) of the system 300 may have a maximum efficiency operating point 830 . The first voltage level 811 that is the magnitude of the inverter voltage Vinv(V) at the maximum efficiency operating point 830 may be calculated.

In one embodiment, the control unit (eg, the control unit 316 of FIG. 3 ) is configured to compare the power transfer efficiency ( %), the ratio (Δη/ΔVinv) of the change amount (Δη) can be calculated. The control unit 316 may calculate the ratio (Δη/ΔVinv) of the inverter voltage change amount (ΔVinv) at the time of measurement and the change amount (Δη) of the power transmission efficiency (%) of the system 300 . The controller 316 may calculate the ratio (Δη/ΔVinv) of the inverter voltage change amount (ΔVinv) and the change amount (Δη) of the power transmission efficiency (%) of the system 300 in real time. The control unit 316 calculates the ratio (Δη/ΔVinv) of the change amount (Δη) of the power transfer efficiency (%) of the system 300 compared to the inverter voltage change amount (ΔVinv) in the first time range 801 in the first ratio ( A1) can be calculated. The first ratio A1 may be about 2. The control unit 316 calculates the ratio (Δη/ΔVinv) of the change amount (Δη) of the power transfer efficiency (%) of the system 300 compared to the inverter voltage change amount (ΔVinv) in the second time range (802) in the second ratio ( A2) can be calculated. The second ratio A2 may be about 1.5. The control unit 316 calculates the ratio (Δη/ΔVinv) of the change amount (Δη) of the power transfer efficiency (%) of the system 300 with the inverter voltage change amount (ΔVinv) in the third time range 803 in the third ratio ( A3) can be calculated. The third ratio A3 may be about 1. The control unit 316 may determine whether the ratio (Δη/ΔVinv) of the calculated inverter voltage change amount ΔVinv and the change amount Δη of the power transmission efficiency (%) of the system 300 corresponds to a specific value. The control unit 316 may determine whether the ratio (Δη/ΔVinv) of the calculated inverter voltage change amount ΔVinv and the change amount Δη of the power transmission efficiency (%) of the system 300 is within a specific range.

In an embodiment, the control unit 316 multiplies each of the calculated ratios A1, A2, and A3 by the reference inverter voltage change amount ΔVdefault in each of the plurality of time ranges 801, 802, and 803, the inverter voltage It can be set as the amount of change (ΔVinv). The controller 316 may set a value obtained by multiplying the reference inverter voltage variation ΔVdefault by the first ratio A1 in the first time range 801 as the inverter voltage variation ΔVinv. The controller 316 may set a value obtained by multiplying the reference inverter voltage variation ΔVdefault by the second ratio A2 in the second time range 802 as the inverter voltage variation ΔVinv. The controller 316 may set a value obtained by multiplying the reference inverter voltage variation ΔVdefault by the third ratio A3 in the third time range 803 as the inverter voltage variation ΔVinv.

In one embodiment, when the inverter voltage Vinv(V) is changed by the inverter voltage change amount ΔVinv having a magnitude that is dynamically changed every first period, it takes until the number of changes and the maximum efficiency operating point 830 are tracked time may be reduced. For example, when the inverter voltage (Vinv(V)) is changed by the inverter voltage change amount (ΔVinv) having a magnitude that is dynamically changed every first period, the maximum efficiency operating point 830 through 9 iteration changes. can be tracked.

In an embodiment, although the inverter voltage Vinv(V) is set to have a dynamically changing magnitude in FIG. 8 , the present invention is not limited thereto, and the driving frequency may be set to have a dynamically changing magnitude.

9 is a graph 900 illustrating adjustment of maximum efficiency operating point tracking periods T1 and T2 based on the efficiency of a system (eg, the system 300 of FIG. 3 ) according to an exemplary embodiment.

In an embodiment, the first graph 910 may represent an inverter voltage Vinv(V) over time. The inverter voltage Vinv(V) may change by the inverter voltage change amount ΔVinv having a constant magnitude for each maximum efficiency operating point tracking period T1 and T2.

In an embodiment, the second graph 920 may represent the power transmission efficiency (%) of the system 300 over time. The power transfer efficiency (%) of the system 300 may have a maximum efficiency operating point 930 . The first voltage level 911 that is the magnitude of the inverter voltage Vinv(V) at the maximum efficiency operating point 930 may be calculated.

In one embodiment, the control unit (eg, the control unit 316 of FIG. 3 ) determines the change amount Δη of the power transmission efficiency (%) of the system 300 over time in each of the plurality of time ranges 901 and 902 . can be calculated. The controller 316 may calculate the maximum efficiency operating point tracking period T1 and T2 according to the change amount Δη of the power transmission efficiency (%) of the system 300 according to time. The control unit 316 sets the maximum efficiency operating point tracking period as the first period T1 based on the change amount Δη of the power transmission efficiency (%) of the system 300 over time in the first time range 901 . can The first period T1 may be about 50 ms. The control unit 316 sets the maximum efficiency operating point tracking period to the second period T2 based on the change amount Δη of the power transmission efficiency (%) of the system 300 over time in the second time range 902 . can The second period T2 may be about 100 ms.

In an embodiment, the controller 316 changes the inverter voltage Vinv by the inverter voltage change amount ΔVinv for each maximum efficiency operating point tracking period T1 and T2 set in each of the plurality of time ranges 901 and 902 . can do it The controller 316 may change the inverter voltage Vinv by the inverter voltage change amount ΔVinv for each first period T1 in the first time range 901 . The controller 316 may change the inverter voltage Vinv by the inverter voltage change amount ΔVinv every second period T2 in the second time range 902 .

In an embodiment, when the maximum efficiency operating point tracking period T1 and T2 for changing the inverter voltage Vinv(V) is dynamically changed, the time required to track the maximum efficiency operating point 930 may be reduced. can For example, if the maximum efficiency operating point tracking period (T1, T2) that changes the inverter voltage (Vinv(V)) is dynamically changed, 15 iteration changes are performed faster to achieve the maximum efficiency operating point (930). ) can be traced.

In an embodiment, the period for changing the inverter voltage Vinv(V) is dynamically set in FIG. 9 , but the present invention is not limited thereto, and the period for changing the driving frequency may be dynamically set.

10 is a graph showing adjusting the inverter voltage change amount (ΔVinv) and the maximum efficiency operating point tracking period (T1, T2) based on the efficiency of the system (eg, the system 300 of FIG. 3 ) according to an embodiment ( 1000).

In an embodiment, the first graph 1010 may represent an inverter voltage Vinv(V) over time. The inverter voltage Vinv(V) may change by the inverter voltage change amount ΔVinv for each first period.

In an embodiment, the second graph 1020 may represent the power transmission efficiency (%) of a system (eg, the system 300 of FIG. 3 ) over time. The power transfer efficiency (%) of the system 300 may have a maximum efficiency operating point 1030 . The first voltage level 1011 that is the magnitude of the inverter voltage Vinv(V) at the maximum efficiency operating point 1030 may be calculated.

In one embodiment, the control unit (eg, the control unit 316 in FIG. 3 ) is configured to compare the power transfer efficiency ( %), calculating the ratio (Δη/ΔVinv) of the change (Δη) of the maximum efficiency operating point tracking period (T1 , T2) can be calculated

In one embodiment, the control unit 316 is a plurality of time ranges ( 1001 , 1002 , 1003 ) the ratio of the change amount (Δη) of the power transfer efficiency (%) of the system 300 compared to the inverter voltage change amount (ΔVinv) ( While varying the magnitude of the inverter voltage change amount ΔVinv according to Δη/ΔVinv), at the same time, the maximum efficiency operating point tracking period T1 according to the change amount Δη of the power transfer efficiency (%) of the system 300 over time , T2) can be changed. The controller 316 may simultaneously change the magnitude of the inverter voltage variation ΔVinv and the maximum efficiency operating point tracking periods T1 and T2 to more quickly track the maximum efficiency operating point 1030 .

The power transmission device 310 according to various embodiments includes a power supply unit (eg, the power supply unit 311 of FIG. 3 ), a converter (eg, the converter 312 of FIG. 3 ), and an inverter (eg, the inverter 313 of FIG. 3 ). , a transmission coil (eg, the transmission coil 315 of FIG. 3 ), and a control unit (eg, the control unit 316 of FIG. 3 ). The control unit 316 obtains a rectified voltage (eg, the rectified voltage Vrect of FIG. 3 ) from the power receiving device (eg, the power receiving device 320 of FIG. 3 ), and is related to power transmission of the transmitting coil 315 . Change the first parameter among the plurality of parameters, check whether a difference value between the rectified voltage Vrect and the target rectified voltage is greater than or equal to a threshold value, and maintain the rectified voltage Vrect when the difference value is greater than or equal to the threshold value Adjusts a second parameter among a plurality of parameters based on the change of the first parameter, calculates the power transmission efficiency of the system 300 after the first parameter and the second parameter change, and when the power transmission efficiency increases, the second parameter The maximum efficiency at which the power transmission efficiency of the system 300 is maximized by maintaining the change direction of 1 parameter, and setting the change direction of the first parameter in the opposite direction when the power transmission efficiency is reduced, and changing the first parameter every first period It can be set to track the operating point.

In an embodiment, the plurality of parameters may include an inverter voltage (eg, an inverter voltage Vinv of FIG. 3 ), an operating frequency (eg, an operating frequency Freq of FIG. 5 ), and a duty cycle.

In an embodiment, the first parameter may be an inverter voltage Vinv, and the second parameter may be an operating frequency Freq.

In an embodiment, the first parameter may be an operating frequency Freq, and the second parameter may be an inverter voltage Vinv.

In an embodiment, the controller 316 may dynamically change the amount of change of the first parameter in each of a plurality of time ranges (eg, a plurality of time ranges 801 , 802 , and 803 of FIG. 8 ).

In an embodiment, the control unit 316 controls ratios of the amount of change in the power transmission efficiency of the system 300 compared to the amount of change of the first parameter in each of the plurality of time ranges 801 , 802 , and 803 (eg, FIG. calculate each of the first rate (A1), the second rate (A2), and/or the third rate (A3) of 8, and the reference amount of change in each of the plurality of time ranges 801, 802, 803 (eg : A value obtained by multiplying the reference inverter voltage variation (Vdefault) of FIG. 8 by each of the calculated ratios A1, A2, and A3 may be set as the variation amount of the first parameter.

In an embodiment, the control unit 316 controls the first period (eg, the first period T1 of FIG. 9 ) over a plurality of time ranges (eg, a plurality of time ranges 901 and 902 of FIG. 9 )). Each can be changed dynamically.

In an embodiment, the controller 316 calculates a change in the power transmission efficiency of the system 300 over time in each of the plurality of time ranges 901 and 902 , and the power transmission efficiency of the system 300 over time The maximum efficiency operating point tracking period is calculated as the first period T1 or a second period different from the first period T1 (eg, the second period T2 in FIG. 9 ) according to the amount of change of , and a plurality of times The first parameter may be changed by the first parameter change amount for each first period T1 or second period T2 set in each of the

ranges

901 and 902 .

In one embodiment, it further includes a communication circuit (eg, the first communication circuit 317 of FIG. 2 ) for wirelessly communicating in-band or out-of-band, wherein the control unit 315 is It may be configured to acquire data regarding the rectified voltage Vrect.

In an embodiment, the rectified voltage Vrect may have a size specified according to the type of the power receiving device 320 , a rated voltage standard, and/or an international standard for wireless power transmission.

The maximum efficiency operating point tracking method using the system 300 including the power transmitting device 310 and the power receiving device 320 according to various embodiments includes obtaining a rectified voltage Vrect from the power receiving device 320 . An operation (eg, operation 410 of FIG. 4 ), an operation of determining whether a difference value between the rectified voltage Vrect and the target rectified voltage is equal to or greater than a threshold value (eg, operation 420 of FIG. 4 ), an operation of determining whether the difference value is greater than or equal to the threshold value In the case of an operation of changing a first parameter among a plurality of parameters related to power transmission of the transmitting coil 315 (eg, operation 430 of FIG. 4 ), a plurality of based on the change of the first parameter so that the rectified voltage Vrect is maintained. An operation of adjusting the second parameter among the parameters of (eg, operation 440 of FIG. 4 ), an operation of calculating the power transmission efficiency of the system 300 after the first parameter and the second parameter are changed (eg, operation 440 of FIG. 4 ) operation 450), maintaining the change direction of the first parameter when the power transmission efficiency increases, and reversely setting the change direction of the first parameter when the power transmission efficiency decreases (eg, operation 460 of FIG. 4 ), and the first It may include an operation (eg, operation 470 of FIG. 4 ) of tracking a maximum efficiency operating point at which power transmission efficiency is maximized by changing a parameter every first period.

In an embodiment, the operation of tracking the maximum efficiency operating point (operation 470 ) may include an operation of dynamically changing the amount of change of the first parameter in each of the plurality of time ranges 801 , 802 , and 803 .

In one embodiment, the operation of tracking the maximum efficiency operating point (operation 470 ) is a measure of the power transfer efficiency of the system 300 compared to the amount of change of the first parameter in each of the plurality of time ranges 801 , 802 , 803 . An operation of calculating each of the rates of change A1, A2, and A3, and each of the rates A1, A2, and A3 calculated for the reference change amount Vdefault in each of the plurality of time ranges 801, 802, and 803 It may include an operation of setting the multiplied value by the change amount of the first parameter.

In an embodiment, the operation of tracking the maximum efficiency operating point (operation 470 ) may include dynamically changing the first period in each of the plurality of time ranges 901 and 902 .

In one embodiment, the operation of tracking the maximum efficiency operating point (operation 470 ) is an operation of calculating the amount of change in the power transmission efficiency of the system 300 over time in each of the plurality of time ranges 901 and 902 , in time Calculating the maximum efficiency operating point tracking period as a first period (T1) or a second period (T2) different from the first period (T1) according to the amount of change in the power transmission efficiency of the system 300 according to an operation, and a plurality of times The operation may include changing the first parameter by the amount of change of the first parameter for each first period T1 or second period T2 set in each of the

ranges

901 and 902 .

In an embodiment, the operation of obtaining the rectified voltage Vrect (operation 410) includes obtaining data regarding the rectified voltage Vrect from the communication circuit 317 for wirelessly communicating in-band or out-of-band. may include

The electronic device according to various embodiments disclosed in this document may have various types of devices. The electronic device may include, for example, a portable communication device (eg, a smart phone), a computer device, a portable multimedia device, a portable medical device, a camera, a wearable device, or a home appliance device. The electronic device according to the embodiment of the present document is not limited to the above-described devices.

The various embodiments of this document and the terms used therein are not intended to limit the technical features described in this document to specific embodiments, but it should be understood to include various modifications, equivalents, or substitutions of the embodiments. In connection with the description of the drawings, like reference numerals may be used for similar or related components. The singular form of the noun corresponding to the item may include one or more of the item, unless the relevant context clearly dictates otherwise. As used herein, "A or B", "at least one of A and B", "at least one of A or B", "A, B or C", "at least one of A, B and C", and "A , B, or C" each may include any one of the items listed together in the corresponding one of the phrases, or all possible combinations thereof. Terms such as "first", "second", or "first" or "second" may be used simply to distinguish the element from other elements in question, and may refer to elements in other aspects (e.g., importance or order) is not limited. It is said that one (eg, first) component is "coupled" or "connected" to another (eg, second) component, with or without the terms "functionally" or "communicatively". When referenced, it means that one component can be connected to the other component directly (eg by wire), wirelessly, or through a third component.

The term “module” used in various embodiments of this document may include a unit implemented in hardware, software, or firmware, and is interchangeable with terms such as, for example, logic, logic block, component, or circuit. can be used as A module may be an integrally formed part or a minimum unit or a part of the part that performs one or more functions. For example, according to an embodiment, the module may be implemented in the form of an application-specific integrated circuit (ASIC).

According to various embodiments of the present document, one or more instructions stored in a storage medium (eg, internal memory 136 or external memory 138) readable by a machine (eg, electronic device 101) may be implemented as software (eg, the program 140) including For example, a processor (eg, processor 120 ) of a device (eg, electronic device 101 ) may call at least one command among one or more commands stored from a storage medium and execute it. This makes it possible for the device to be operated to perform at least one function according to the called at least one command. The one or more instructions may include code generated by a compiler or code executable by an interpreter. The device-readable storage medium may be provided in the form of a non-transitory storage medium. Here, 'non-transitory' only means that the storage medium is a tangible device and does not contain a signal (eg, electromagnetic wave), and this term refers to the case where data is semi-permanently stored in the storage medium and It does not distinguish between temporary storage cases.

According to one embodiment, the method according to various embodiments disclosed in this document may be provided as included in a computer program product. Computer program products may be traded between sellers and buyers as commodities. The computer program product is distributed in the form of a machine-readable storage medium (eg compact disc read only memory (CD-ROM)), or via an application store (eg Play Store™) or on two user devices ( It can be distributed online (eg download or upload), directly between smartphones (eg smartphones). In the case of online distribution, at least a part of the computer program product may be temporarily stored or temporarily generated in a machine-readable storage medium such as a memory of a server of a manufacturer, a server of an application store, or a relay server.

According to various embodiments, each component (eg, module or program) of the above-described components may include a singular or a plurality of entities, and some of the plurality of entities may be separately disposed in other components. have. According to various embodiments, one or more components or operations among the above-described corresponding components may be omitted, or one or more other components or operations may be added. Alternatively or additionally, a plurality of components (eg, a module or a program) may be integrated into one component. In this case, the integrated component may perform one or more functions of each component of the plurality of components identically or similarly to those performed by the corresponding component among the plurality of components prior to the integration. . According to various embodiments, operations performed by a module, program, or other component are executed sequentially, in parallel, repeatedly, or heuristically, or one or more of the operations are executed in a different order, or omitted. or one or more other operations may be added.

Claims

In the power transmission device,

power supply;

converter;

inverter;

transmitting coil; and

comprising a control unit;

The control unit is

obtaining a rectified voltage from the power receiving device;

changing a first parameter among a plurality of parameters related to power transmission of the transmitting coil;

check whether the difference value between the rectified voltage and the target rectified voltage is greater than or equal to a threshold value;

adjusting a second parameter among the plurality of parameters based on a change in the first parameter so that the rectified voltage is maintained when the difference value is equal to or greater than the threshold value;

calculating the power transmission efficiency of the system after the first parameter and the second parameter change;

When the power transmission efficiency increases, the direction of change of the first parameter is maintained, and when the power transmission efficiency decreases, the direction of change of the first parameter is reversed;

The power transmission apparatus is configured to change the first parameter every first period to track a maximum efficiency operating point at which the power transmission efficiency of the system is maximized.
The method according to claim 1,

The plurality of parameters may include an inverter voltage, an operating frequency, and a duty cycle.
3. The method according to claim 2,

The first parameter is the inverter voltage, and the second parameter is the operating frequency.
3. The method according to claim 2,

The first parameter is the operating frequency, and the second parameter is the inverter voltage.
The method according to claim 1,

The control unit dynamically changes the amount of change of the first parameter in each of a plurality of time ranges.
The method according to claim 5, wherein the control unit,

calculating each of the ratios of the amount of change in the power transmission efficiency of the system compared to the amount of change in the first parameter in each of the plurality of time ranges, and

A power transmission apparatus for setting a value obtained by multiplying a reference change amount by each of the calculated ratios in each of the plurality of time ranges as the change amount of the first parameter.
The method according to claim 1,

The control unit dynamically changes the first period in each of a plurality of time ranges.
The method according to claim 7, wherein the control unit,

calculating a change in the power transmission efficiency of the system with time in each of the plurality of time ranges;

calculating a maximum efficiency operating point tracking period as a second period different from the first period or the second period according to the amount of change in the power transmission efficiency of the system according to the time; and

The power transmission apparatus for changing the first parameter by the amount of change of the first parameter for each of the first period or the second period set in each of the plurality of time ranges.
The method according to claim 1,

Communication circuitry for wirelessly communicating with the power receiving device in-band or out-of-band;

The control unit is a power transmission device configured to obtain data related to the rectified voltage from the communication circuit.
The method according to claim 1,

The rectified voltage is a type of the power receiving device, a rated voltage standard, and/or a power transmission device having a size specified according to an international standard for wireless power transmission.
A method for tracking a maximum efficiency operating point of a system including a power transmitting device and a power receiving device, the method comprising:

obtaining a rectified voltage from the power receiving device;

checking whether a difference value between the rectified voltage and a target rectified voltage is greater than or equal to a threshold value;

changing a first parameter among a plurality of parameters related to power transmission of a transmitting coil when the difference value is equal to or greater than the threshold value;

adjusting a second parameter among the plurality of parameters based on a change in the first parameter so that the rectified voltage is maintained;

calculating power transmission efficiency of the system after the first parameter and the second parameter change;

maintaining a change direction of the first parameter when the power transmission efficiency increases, and reversely setting a change direction of the first parameter when the power transmission efficiency decreases; and

and tracking a maximum efficiency operating point at which the power transmission efficiency of the system is maximized by changing the first parameter every first period.
12. The method of claim 11,

wherein the plurality of parameters include an inverter voltage, an operating frequency, and a duty cycle.
13. The method of claim 12,

The first parameter is the inverter voltage and the second parameter is the operating frequency.
13. The method of claim 12,

wherein the first parameter is the operating frequency and the second parameter is the inverter voltage.
The method of claim 11 , wherein the tracking of the maximum efficiency operating point comprises:

and dynamically varying the amount of change of the first parameter in each of a plurality of time ranges.