Wireless power receiving device and power compensation method for wireless charging

Abstract

A wireless power receiving device disclosed herein wirelessly receives power according to a single-phase mode or a three-phase mode. The wireless power receiving device comprises a compensation circuit including a three-phase inductor assembly. The three-phase inductor assembly includes: three inductors each carrying a current of a different phase; three outer legs in which an outer magnetic flux path is formed; and a middle leg in which a central magnetic flux path is formed. Accordingly, problems such as system instability, increased reactive power, and decreased efficiency due to mode switching between single-phase and three-phase wireless charging modes can be effectively solved.

Description

Wireless power receiver and power compensation method for wireless charging

[0001] The present invention relates to a wireless power receiving device and a power compensation method for wireless charging, and more particularly, to a wireless power receiving device that wirelessly receives power according to a charging operation mode and a power compensation method for wireless charging.

[0002] In the case of electric vehicle wireless charging systems, according to the international standard SAE J2954, a certain level of standards is presented for single-phase wireless charging systems up to WPT3 (11 kW) class regarding input / output characteristics, compensation networks, and charging pad specifications.

[0003] On the other hand, there is no clear standard yet for high-power multi-phase wireless charging systems above WPT4 (22kVA), for which research is currently in progress, such as three-phase wireless charging systems.

[0004] In this situation, some research papers and patents have been proposed on wireless charging pads and receivers that are compatible with both single-phase and multi-phase wireless charging stations. However, most of them are limited to wireless pad design, and there is almost no technology that presents specific solutions to problems such as reduced operational stability, efficiency loss, or power quality degradation that may occur during single-phase / multi-phase operation.

[0005] In particular, the current phase changes when switching between single-phase and three-phase modes, which causes the equivalent inductance of the pad to change. This change affects the reactance component of the compensation network, which increases the reactive power within the system and may cause problems under zero-current switching operation conditions in the input inverter. This may lead to adverse effects such as reduced system efficiency, increased heat generation in the switching elements, or damage to the inverter.

[0006] However, there is a lack of specific and feasible technical proposals regarding receiver compensation topology or control technology to effectively solve the problem of electrical characteristic changes that occur due to the change in single-phase / three-phase charging mode as described above.

[0007] In order to solve the above problems, one object of the present disclosure is to provide a wireless power receiving device that can effectively resolve problems arising from mode switching between single-phase and three-phase wireless charging methods.

[0008] Another object of the present disclosure is to provide a power compensation method for wireless charging that can effectively resolve problems arising from mode switching between single-phase and three-phase wireless charging methods.

[0009] According to embodiments of the present disclosure for achieving the above object, a wireless power receiver receives power wirelessly in a single-phase mode or a three-phase mode. The wireless power receiver is configured according to an inductor-capacitor-capacitor resonance topology (LCC resonance topology) and includes a compensation circuit including a three-phase coupled inductor. The three-phase inductor receiver includes a first inductor, a second inductor, and a third inductor, each of which has a current of a different phase flowing therethrough, three outer legs in which an outer magnetic flux path is formed by the first inductor, the second inductor, and the third inductor, and a central leg in which a central magnetic flux path is formed by the first inductor, the second inductor, and the third inductor.

[0010] In one embodiment, the three-phase inductor combination can maintain a resonant condition by compensating for equivalent inductance and reactance that change according to the transition between single-phase mode and three-phase mode.

[0011] In one embodiment, the number of turns wound on the intermediate leg and the number of turns wound on the outer leg are determined according to a preset turns ratio, and the turns ratio can be set so that the equivalent inductance satisfies the resonance condition in a single-phase or three-phase operation mode.

[0012] In one embodiment, the first inductor, the second inductor, and the third inductor may each be wound on the three outer groups.

[0013] In one embodiment, the first inductor, the second inductor, and the third inductor may be wound alternately on the intermediate group.

[0014] In one embodiment, the first inductor, the second inductor, and the third inductor may be wound on the three outer groups, respectively, and may be wound alternately on the middle group.

[0015] In one embodiment, the intermediate and the outer legs provide a magnetic flux path such that each magnetic flux formed in the first inductor, the second inductor, and the third inductor passes through the intermediate legs to form a closed loop with at least one of the outer legs.

[0016] In one embodiment, the system may further include a control circuit that detects the number of phases or the current distribution between phases of the wirelessly received power, thereby detecting a switch in the operating mode between the single-phase mode and the three-phase mode.

[0017] In one embodiment, the compensation circuit may be controlled to operate in either a constant current (CC) mode or a constant voltage (CV) mode based on the operating mode of the wirelessly received power.

[0018] In one embodiment, the compensation circuit may be controlled to operate in a constant current (CC) mode based on the fact that the power received wirelessly is in a three-phase mode.

[0019] In one embodiment, the compensation circuit may be controlled to operate in a constant voltage (CV) mode based on the wirelessly received power being in single-phase mode.

[0020] In order to achieve the above object, a compensation circuit of a wireless power receiver according to embodiments of the present disclosure wirelessly receives power in a single-phase mode or a three-phase mode. The compensation circuit of the wireless power receiver is configured according to an inductor-capacitor-capacitor resonance topology (LCC resonance topology) and includes a three-phase coupled inductor. The three-phase inductor combination includes a first inductor, a second inductor, and a third inductor, each of which has a current of a different phase flowing therethrough, three outer legs in which an outer magnetic flux path is formed by the first inductor, the second inductor, and the third inductor, and a central leg in which a central magnetic flux path is formed by the first inductor, the second inductor, and the third inductor.

[0021] In one embodiment, the first inductor, the second inductor, and the third inductor may each be wound on the three outer groups.

[0022] In one embodiment, the first inductor, the second inductor, and the third inductor may be wound alternately on the intermediate group.

[0023] In one embodiment, the first inductor, the second inductor, and the third inductor may be wound on the three outer groups, respectively, and may be wound alternately on the middle group.

[0024] In order to achieve the above object, a power compensation method for wireless charging according to embodiments of the present disclosure compensates for power received by a wireless power receiver including a compensation circuit configured based on an inductor-capacitor-capacitor resonance topology (LCC) and a control unit that controls the compensation circuit. The power compensation method for wireless charging includes a step of detecting, in the control unit, the number of phases of power wirelessly received or a distribution of current between phases to determine a current operation mode among a single-phase mode or a three-phase mode, and a step of controlling, in the control unit, to compensate for equivalent inductance and reactance according to the current operation mode through a three-phase inductor combination including three outer legs in which an outer magnetic flux path is formed by a first inductor, a second inductor, and a third inductor, and a central leg in which a central magnetic flux path is formed by the first inductor, the second inductor, and the third inductor.

[0025] In one embodiment, the step of controlling to compensate for the equivalent inductance and reactance may include a step of switching between a constant current (CC) mode and a constant voltage (CV) mode based on the current operating mode.

[0026] In one embodiment, the step of controlling to compensate for the equivalent inductance and reactance may include a step of controlling to operate in a constant current (CC) mode based on the fact that the power received wirelessly is in a three-phase mode.

[0027] In one embodiment, the step of controlling to compensate for the equivalent inductance and reactance may include a step of controlling to operate in a constant voltage (CV) mode based on the fact that the power received wirelessly is in a single-phase mode.

[0028] According to embodiments of the present disclosure, problems such as system instability, increase in reactive power, and decrease in efficiency that may occur due to changes in equivalent inductance of pads due to mode switching between single-phase and three-phase wireless charging methods can be effectively resolved.

[0029] FIG. 1 is a conceptual diagram of an example of a wireless power transfer (WPT) system for an electric vehicle to which one embodiment of the present invention is applied.

[0030] Figures 2 and 3 are conceptual diagrams of the x, y, and z axes specified in SAE J2954 that can be applied to one embodiment of the present invention.

[0031] FIG. 4 is a conceptual diagram illustrating an electric vehicle wireless charging circuit according to one embodiment of the present invention.

[0032] FIG. 5 is an equivalent circuit of a single-phase wireless power transfer (WPT) system according to one embodiment of the present invention.

[0033] FIG. 6 is a conceptual cross-sectional view and an elevation view of a wireless power transmission pad according to one embodiment of the present invention.

[0034] Figure 7 is a conceptual diagram for explaining a wireless power receiving device according to one embodiment of the present invention.

[0035] Fig. 8 is a circuit diagram showing an embodiment of a specific configuration of the wireless power receiving device illustrated in Fig. 7.

[0036] FIG. 9 is a perspective view illustrating one embodiment of a three-phase inductor combination of the circuit diagram illustrated in FIG. 8.

[0037] FIG. 10 is a perspective view illustrating another embodiment of the three-phase inductor combination of the circuit diagram illustrated in FIG. 8.

[0038] FIG. 11 is a perspective view illustrating another embodiment of the three-phase inductor combination of the circuit diagram illustrated in FIG. 8.

[0039] Fig. 12 is an equivalent circuit diagram of the three-phase inductor combination of Fig. 11.

[0040] Fig. 13 is a circuit diagram illustrating an example of operation in a constant current mode based on the operation mode of power received from the wireless power receiving device of Fig. 7.

[0041] Fig. 14 is a circuit diagram illustrating an example of operation in a constant voltage mode based on the operation mode of power received from the wireless power receiving device of Fig. 7.

[0042] FIG. 15 and FIG. 16 are circuit diagrams showing other embodiments of the specific configuration of the wireless power receiving device illustrated in FIG. 7.

[0043] Fig. 17 is a flowchart illustrating a power compensation method for wireless charging according to one embodiment of the present invention.

[0044] FIG. 18 is a block diagram illustrating a generalized configuration of hardware that controls a sequence for wireless power transmission included in a wireless power receiving device of the present invention or related to a wireless power receiving device.

[0045] The present invention is susceptible to various modifications and embodiments. Specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention. Throughout the description of each drawing, similar reference numerals have been used to designate similar components.

[0046] Terms such as "first," "second," "A," and "B" may be used to describe various components, but these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, the first component could be referred to as the "second component," and similarly, the second component could also be referred to as the "first component." The term "and / or" includes any combination of multiple related items listed or any one of multiple related items listed.

[0047] In the embodiments of the present application, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.” Furthermore, in the embodiments of the present application, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.”

[0048] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0049] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprise" or "have" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0050] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0051] Meanwhile, even if a technology was known prior to the filing date of this application, it may be included as part of the composition of the invention of this application, if necessary, and such technology will be described in this specification to the extent that it does not obscure the spirit of the invention. However, in describing the composition of the invention of this application, a detailed description of matters that were known prior to the filing date of this application and would be clearly understood by those skilled in the art may obscure the spirit of the invention, and therefore, an excessively detailed description of the known technology will be omitted.

[0052] Some terms used in this specification are defined as follows:

[0053] An electric vehicle (EV) may refer to an automobile as defined in 49 CFR (Code of Federal Regulations) 523.3, among other provisions. An EV is capable of highway travel and can be powered by electricity supplied by an onboard energy storage device, such as a rechargeable battery, from an external power source. This power source may include a residential or public power service, or a generator powered by onboard fuel.

[0054] An electric vehicle (EV) can be referred to as an electric car, electric automobile, ERV (electric road vehicle), PV (plug-in vehicle), xEV (plug-in vehicle), etc., and an xEV can be referred to as or distinguished as a BEV (plug-in all-electric vehicle or battery electric vehicle), PEV (plug-in electric vehicle), HEV (hybrid electric vehicle), HPEV (hybrid plug-in electric vehicle), PHEV (plug-in hybrid electric vehicle), etc.

[0055] A plug-in electric vehicle (PEV) can be referred to as an electric vehicle that recharges its onboard primary battery by connecting to the power grid.

[0056] A plug-in vehicle (PV) may be referred to herein as a vehicle that can be recharged wirelessly from an Electric Vehicle Supply Equipment (EVSE) without using a physical plug and socket.

[0057] Heavy duty vehicles (HD Vehicles) may refer to any vehicle with four or more wheels as defined in 49 CFR 523.6 or CFR 37.3 (bus).

[0058] A light-duty plug-in electric vehicle (LDEV) may refer to a vehicle with three or four wheels that is propelled by an electric motor powered by a rechargeable battery or other energy source, primarily intended for use on public streets, roads, and highways. A LEV may be defined as having a gross weight of less than 4.545 kg.

[0059] A wireless power charging system (WCS) may refer to a system for controlling between a Supply Device (or Ground Assembly, GA) and an EV device (or Vehicle Assembly, VA), including wireless power transfer, alignment, and communication.

[0060] Wireless power transfer (WPT) can refer to the transfer of electrical power from an alternating current (AC) power supply network, such as a utility or grid, to an electric vehicle through contactless means.

[0061] A utility provides electrical energy and can be defined as a collection of systems, typically including a Customer Information System (CIS), Advanced Metering Infrastructure (AMI), and a Rates and Revenue system. Utilities enable plug-in electric vehicles to access energy through price lists or discrete events. Utilities can also provide information on tariffs, metered power consumption intervals, and EV program qualifications for plug-in electric vehicles.

[0062] Smart charging can be described as a system where EVSE and / or electric vehicles (including plug-in hybrid electric vehicles) communicate with the power grid to optimize vehicle charge or discharge rates to grid capacity or time of day for cost-to-use ratios.

[0063] Automatic charging can be defined as the act of positioning a vehicle in a suitable location relative to a primary charger assembly capable of transmitting power and charging it either conductively or inductively. Automatic charging can be performed after obtaining the necessary authentication and authorization.

[0064] Interoperability can refer to the state in which components of a system can work together to achieve the intended function of the entire system. Information interoperability can refer to the ability of two or more networks, systems, devices, applications, or components to share information securely and effectively and easily with little or no user inconvenience.

[0065] An inductive charging system can refer to a system that electromagnetically transfers energy in the forward direction from the power supply network to an electric vehicle via a loosely coupled transformer. In this embodiment, the inductive charging system can correspond to an electric vehicle charging system.

[0066] An inductive coupler is a transformer that is formed by a primary device and a secondary device and transmits power through electrical isolation.

[0067] Inductive coupling can refer to the magnetic coupling between two coils. The two coils can refer to the primary coil / ground assembly coil and the secondary coil / vehicle assembly coil.

[0068] A supply power circuit (SPC) / ground assembly (GA) may refer to an assembly disposed on the primary / ground assembly or infrastructure side, including a primary coil / GA coil and other suitable components. The other suitable components may include at least one component for controlling impedance and resonant frequency, ferrite for reinforcing a magnetic path, and electromagnetic shielding materials. For example, the SPC or GA may include a power / frequency conversion device necessary to function as a power source of a wireless charging system, an SPC controller / GA controller, and wiring from the grid, and wiring between each unit and filtering circuits, a housing, etc.

[0069] An EV power circuit (EVPC) / vehicle assembly (VA) may refer to an assembly placed in a vehicle, including a secondary coil / VA coil and other suitable components. The other suitable components may include at least one component for controlling impedance and resonant frequency, ferrite for reinforcing the magnetic path, and electromagnetic shielding materials. For example, an EVPC or VA may include a rectifier / power converter necessary to function as a vehicle component of a wireless charging system, an EVPC controller / VA controller, and wiring for a vehicle battery, as well as wiring between each unit and filtering circuits, a housing, etc.

[0070] The aforementioned SPC may be referred to or distinguished as a ground assembly (GA), etc., and similarly, the EVPC may be referred to or distinguished as a vehicle assembly (VA), etc.

[0071] The aforementioned GA may be referred to as a primary device (PD), a primary device, etc., and similarly, the VA may be referred to as a secondary device (SD), a secondary device, etc.

[0072] The aforementioned GA may be referred to as a supply device, a power supply-side device, etc., and similarly, the VA may be referred to as an electric vehicle device (EV device), an electric vehicle-side device, etc.

[0073] A primary device may be a device external to the electric vehicle that provides contactless coupling to the secondary device. The primary device may be referred to as a primary-side device. When the electric vehicle receives power, the primary device may act as a power source that transmits power. The primary device may include a housing and all covers.

[0074] A secondary device may be a device mounted on an electric vehicle that provides contactless coupling to the primary device. The secondary device may be referred to as a secondary device. When the electric vehicle receives power, the secondary device can transfer power from the primary device to the electric vehicle. The secondary device may include a housing and all covers.

[0075] The supply power electronics may be part of the SPC or GA that regulates the output power level to the primary coil / GA coil based on information from the vehicle. The EV power electronics may be part of the EVPC or VA that monitors certain vehicle parameters during charging and initiates communication with the SPC or GA to control the output power level.

[0076] The supply power electronics described above may be referred to as ground assembly electronics (GA electronics), a ground assembly controller (GA controller), or a primary device communication controller (PDCC), and the electric vehicle power electronics (EV power electronics) may be referred to as vehicle assembly electronics (VA electronics), a vehicle assembly controller (VA controller), or an electric vehicle communication controller (VA controller).

[0077] The magnetic gap may refer to the vertical distance between the highest plane of the upper portion of the litz wire or the upper portion of the magnetic material of the primary coil / GA coil and the lowest plane of the lower portion of the litz wire or the magnetic material of the secondary coil / VA coil when they are aligned with each other.

[0078] Ambient temperature may refer to the ground level temperature measured in the atmosphere of a target subsystem that is not directly exposed to sunlight.

[0079] Vehicle ground clearance can refer to the vertical distance between the road or pavement and the lowest part of the vehicle's floor pan.

[0080] Vehicle magnetic ground clearance may refer to the vertical distance between the lowest plane of the floor of the Litz wire or the insulating material of the secondary coil / VA coil mounted on the vehicle and the road pavement.

[0081] Secondary coil surface distance / Vehicle assembly (VA) coil surface distance may refer to the vertical distance between the bottommost plane of the Litz wire or the magnetic material of the secondary coil / VA coil and the lowest outer surface of the secondary coil / VA coil. This distance may include additional items packaged with protective covering material and coil packaging material.

[0082] The secondary coil described above may be referred to as a VA coil, a vehicle coil, a receiver coil, etc., and similarly, the primary coil may be referred to as a ground assembly coil (GA coil), a transmit coil, etc.

[0083] An exposed conductive component may refer to a conductive component of an electrical device (e.g., an electric vehicle) that can be touched by a person and is not normally conductive but may become conductive in the event of a fault.

[0084] Hazardous live component may refer to a live component that may, under certain conditions, cause a hazardous electric shock.

[0085] Live component may refer to any conductor or conductive part that is electrically active in its basic use.

[0086] Direct contact can refer to contact between living beings, such as humans.

[0087] Indirect contact may refer to contact with exposed, conductive, live components due to an insulation failure (see IEC 61140).

[0088] Alignment may refer to a process of finding the relative position of a secondary device to a primary device for a specified efficient power transfer, and / or a process of finding the relative position of a primary device to a secondary device. In this specification, alignment may refer to, but is not limited to, the positional alignment of a wireless power transfer system.

[0089] Pairing may refer to the process of associating a vehicle (electric vehicle) with a single dedicated ground assembly (primary device) arranged to transfer power. In this specification, pairing may include the process of associating a charging spot or a specific SPC / ground assembly with an EVPC / vehicle assembly controller.

[0090] Correlation / Association may include the process of establishing a relationship between two peer communication entities.

[0091] Command and control communication may refer to communication between an electric vehicle power supply unit and an electric vehicle that exchanges information necessary to initiate, control, and terminate the wireless power transfer process.

[0092] High-level communication can handle all information beyond what command and control communication can handle. Data links for high-level communication can use, but are not limited to, power line communication (PLC).

[0093] Low power excitation may refer to, but is not limited to, activating the electric vehicle to detect the primary device for precision positioning and pairing, and vice versa.

[0094] A Service Set Identifier (SSID) is a unique 32-character identifier attached to the header of packets transmitted over a wireless LAN. The SSID identifies the basic service set (BSS) to which a wireless device is attempting to connect. Essentially, SSIDs distinguish multiple wireless LANs. Therefore, all access points (APs) and terminal / station devices attempting to use a specific wireless LAN can use the same SSID. Devices that do not use a unique SSID cannot join a BSS. Because SSIDs are visible in plaintext, they may not provide any security features to the network.

[0095] The ESSID (Extended Service Set Identifier) ​​is the name of the network you want to connect to. It's similar to the SSID, but can be a more extensive concept.

[0096] A BSSID (Basic Service Set Identifier) ​​is typically 48 bits long and is used to identify a specific BSS (Basic Service Set). For infrastructure BSS networks, the BSSID can be the MAC (Medium Access Control) of the AP device. For independent BSSs or ad hoc networks, the BSSID can be generated with any value.

[0097] A charging station may include at least one ground assembly and at least one ground assembly controller that manages the at least one ground assembly. The ground assembly may include at least one wireless communication device. A charging station may refer to a location equipped with at least one ground assembly, such as a home, office, public space, road, or parking lot.

[0098] In this specification, association may be used as a term meaning the procedure for establishing wireless communication between an Electric Vehicle Communication Controller (EVCC) and a Supply Equipment Communication Controller (SECC) that controls charging infrastructure.

[0099] Electric vehicle charging systems may include, but are not limited to, conductive charging systems using cables or contactless wireless power transfer systems. Essentially, an electric vehicle charging system can be defined as a system that charges the battery mounted on an electric vehicle using power from the commercial power grid or an energy storage device. These systems can take various forms depending on the type of electric vehicle.

[0100] SAE TIR J2954, the leading standard for wireless charging, establishes industry-standard specification guidelines that define acceptance criteria for interoperability, electromagnetic compatibility, minimum performance, safety, and testing for wireless charging of light-duty electric and plug-in electric vehicles.

[0101] A Wireless Communication System (WCS) based on the J2954 standard, which represents an example of a wireless charging system, may consist of a utility interface, a high-frequency power inverter, a coupling coil, a rectifier, a filter, an optional regulator, and communication between the vehicle energy charging / storage system and the power inverter connected to the utility. The utility interface is similar to a conventional EVSE connection to a single-phase or three-phase AC power source.

[0102] Hereinafter, with reference to the attached drawings, preferred embodiments of the present invention will be described in more detail. In order to facilitate an overall understanding in describing the present invention, identical reference numerals will be used for identical components in the drawings, and redundant descriptions of identical components will be omitted.

[0103]

[0104] FIG. 1 is a conceptual diagram of an example of a wireless power transfer (WPT) system for an electric vehicle to which one embodiment of the present invention is applied.

[0105] Referring to FIG. 1, wireless power transfer can be performed by at least one component of an electric vehicle (10) and a charging station (20), and can be used to wirelessly transfer power to the electric vehicle (10).

[0106] However, the electric vehicle (10) according to the present invention may include a hybrid vehicle having both an electric motor and a general internal combustion engine, and may include not only an automobile but also a motorcycle, a cart, a scooter, and an electric bicycle.

[0107] Here, an electric vehicle (10) can be generally defined as a vehicle (automobile) that supplies current induced from a rechargeable energy storage device, such as a battery (12), as an energy source for an electric motor, which is a power device.

[0108] In addition, the electric vehicle (10) may include a receiving pad (11) including a receiving coil to wirelessly charge the battery (12), and may also include a plug connection to charge the battery (12) via a wire. In this case, an electric vehicle (10) capable of charging the battery (12) via a wire may be referred to as a plug-in electric vehicle (PEV).

[0109] Here, the charging station (20) can be connected to a power grid (30) or a power backbone and can provide alternating current (AC) or direct current (DC) power to a transmitting pad (21) including a transmitting coil via a power link.

[0110] In addition, the charging station (20) can communicate with a power grid (30) or an infrastructure management system or infrastructure server that manages the power grid through wired or wireless communication, and can perform wireless communication with an electric vehicle (10). Here, wireless communication may include Bluetooth, Zigbee, cellular, a wireless local area network, etc.

[0111] Additionally, for example, the charging station (20) may be located in various locations, such as a parking lot attached to the home of an electric vehicle owner (10), a parking area for charging electric vehicles at a gas station, a parking area at a shopping center or workplace, etc.

[0112] Here, the process of wirelessly charging the battery (12) of the electric vehicle (10) can be performed by first positioning the receiving pad (11) of the electric vehicle (10) in an energy field by the transmitting pad (21), and then allowing the transmitting coil of the transmitting pad (21) and the receiving coil of the receiving pad (11) to interact or couple with each other. As a result of the interaction or coupling, an electromotive force is induced in the receiving pad (11), and the battery (12) can be charged by the induced electromotive force.

[0113] Additionally, the charging station (20) and the transmitting pad (21) may be referred to as a supply power circuit (SPC) or a ground assembly (GA), in whole or in part, and the SPC or ground assembly may refer to the meaning defined above.

[0114] In addition, the receiving pad (11) of the electric vehicle (10) and all or part of other internal components of the electric vehicle may be referred to as an electric vehicle power circuit (EVPC) or a vehicle assembly (VA), where the EVPC or vehicle assembly may refer to the meaning defined above.

[0115] Here, the transmitting pad (21) or the receiving pad (11) may be configured as non-polarized or polarized.

[0116] Here, if the pad is non-polar, it may have one pole at the center of the pad and an opposite pole at the outer periphery. Here, the flux can be formed to exit at the center of the pad and return at all outer boundaries of the pad.

[0117] Additionally, if the pads are polarized, each end of the pad can have a pole. Here, the magnetic flux can be formed based on the orientation of the pad.

[0118] In the present invention, the transmitting pad (21) or the receiving pad (11) may be collectively referred to as a wireless charging pad.

[0119] Figures 2 and 3 are conceptual diagrams of the x, y, and z axes specified in SAE J2954 that can be applied to one embodiment of the present invention.

[0120] Referring to FIGS. 2 and 3, in the right-hand coordinate system, the forward or front-back direction of the vehicle can be defined as the x-axis, the driver side for a left-hand side vehicle or the left and right sides of the vehicle can be defined as the y-axis, the upward or up-and-down direction of the vehicle can be defined as the z-axis, the magnetic center of the coil of the transmitting pad (21) or receiving pad (11) can be defined as x=0 and y=0, and the ground surface can be defined as z=0.

[0121] FIG. 4 is a conceptual diagram illustrating an electric vehicle wireless charging circuit according to one embodiment of the present invention.

[0122] The circuit on the left side of Fig. 4 can be interpreted as representing all or part of the power supplied from the power grid (Vsrc), the charging station (20) in Fig. 1, and the configuration of the transmitting pad (21), and the circuit on the right side of Fig. 4 can be interpreted as representing all or part of the electric vehicle including the receiving pad and the battery.

[0123] The left circuit of Fig. 4 provides output power (Psrc) corresponding to power (Vsrc) supplied from a power grid to a wireless charging power converter, and the wireless charging power converter can output power (P1) obtained by performing AC / DC conversion and the frequency of the provided power (Psrc) so as to emit an electromagnetic field at a desired operating frequency from a transmitting coil (L1).

[0124] The wireless charging power converter may include at least one of an AC / DC converter that converts AC power supplied from the power grid (Psrc) into DC power, and a low-frequency converter (or LF converter) that converts DC power into power at an operating frequency suitable for wireless charging. The operating frequency may be determined to be, for example, between 80 and 90 kHz, but is not limited thereto.

[0125] The power (P1) output from the wireless charging power converter can be supplied again to a circuit composed of a transmitting coil (L1), a first capacitor (C1), and a first resistor (R1). At this time, the first capacitor (C1) can be determined to have an element value that allows it to have an operating frequency suitable for charging together with the transmitting coil (L1). In addition, the first resistor (R1) here can mean a power loss generated by the transmitting coil (L1) and the first capacitor (C1).

[0126] Here, the transmitting coil (L1) and the receiving coil (L2) are electromagnetically coupled, defined by a coupling coefficient m, so that power can be transmitted, or power can be induced to the receiving coil (L2). Therefore, in the present invention, the meaning of power being transmitted can be used interchangeably with the meaning of power being induced.

[0127] Here, the power (P2) induced or transmitted to the receiving coil can be provided to the electric vehicle power converter. At this time, the second capacitor (C2) can be determined to have an element value that allows it to have an operating frequency suitable for charging together with the receiving coil (L2), and the second resistor (R2) can mean the power loss generated by the receiving coil (L2) and the second capacitor (C2).

[0128] The electric vehicle power converter may include an LF / DC converter that converts the provided power (P2) at a specific operating frequency back into DC power having a voltage level suitable for the battery (VHV) of the electric vehicle.

[0129] When the electric vehicle power converter converts the provided power (P2) into power (PHV), the output power (PHV) can be used to charge the battery (VHV) built into the electric vehicle.

[0130] The right circuit of Fig. 4 may further include a switch for selectively connecting or disconnecting the receiving coil (L2) from the battery (VHV).

[0131] The resonance frequencies of the transmitting coil (L1) and the receiving coil (L2) can be configured to be similar or identical to each other, and the receiving coil (L2) can be configured to be positioned at a close range to the electromagnetic field generated by the transmitting coil (L1).

[0132] The circuit of FIG. 4 should be understood as an exemplary circuit for power transmission in an electric vehicle wireless charging system available for embodiments of the present invention, and the spirit of the present invention is not limited to the circuit of FIG. 4.

[0133] Meanwhile, since power loss may increase as the distance between the transmitting coil (L1) and the receiving coil (L2) increases, setting the positions of the two may be an important factor.

[0134] At this time, the transmitting coil (L1) may be included in the transmitting pad (21) in Fig. 1, and the receiving coil (L2) may be included in the receiving pad (11) in Fig. 1. In addition, the transmitting coil may be referred to as a primary coil or a GA coil (Ground Assembly coil), and the receiving coil may be referred to as a secondary coil or a VA coil (Vehicle Assembly coil). Therefore, the mutual positioning of the transmitting pad (21) and the receiving pad (11) or the mutual positioning of the electric vehicle (10) and the transmitting pad (21) is also an important factor.

[0135] The positional alignment between the transmitting pad (21) in FIG. 1 and the receiving pad (11) built into the electric vehicle (10) may correspond to the previously described term alignment, and therefore, may be defined as the positional alignment between the SPC / GA and the EVPC / VA, and is not limited to the positional alignment of the transmitting pad (21) and the receiving pad (11).

[0136] Depending on the embodiment, the transmission pad (21) may be located below the ground surface, above the ground surface, or may be located so that the upper surface of the transmission pad (21) is exposed below the ground surface. At this time, as shown in FIGS. 2 and 3, the x-axis may indicate the front-back direction of the vehicle, the y-axis may indicate the left-right direction of the vehicle, and the z-axis may indicate the up-down direction of the vehicle.

[0137] In addition, the receiving pad (11) of the electric vehicle can be defined by different categories according to the height measured from the ground surface (defined in the z direction), and for example, if the height of the receiving pad (11) from the ground surface is 100-150 (mm), it can be set as class 1, if it is 140-210 (mm), it can be set as class 2, and if it is 170-250 (mm), it can be set as class 3. At this time, partial support may be possible, such as supporting only class 1 or supporting both classes 1 and 2, depending on the receiving pad (11).

[0138] The height measured relative to the ground surface can correspond to the vehicle magnetic ground clearance, a term previously described.

[0139] In addition, the position of the transmission pad (21) in the height direction (defined in the z direction) can be determined to be located between the maximum class and the minimum class supported by the reception pad (11). For example, if the reception pad (11) supports only classes 1 and 2, the transmission pad can be determined to be located between 100 and 210 (mm) from the reception pad (11).

[0140] Additionally, the gap between the center of the transmitting pad (21) and the center of the receiving pad (11) can be determined to be located within limits in the horizontal and vertical directions (defined in the y and x directions). For example, it can be determined to be located within ±75 (mm) in the horizontal direction (defined in the y direction), and it can be determined to be located within ±100 (mm) in the vertical direction (defined in the x direction).

[0141] Here, the relative positions of the transmitting pad (21) and the receiving pad (11) may have different limits depending on the experimental results, and the above figures should be understood as exemplary.

[0142] In addition, the transmission pad (21) and the reception pad (11) are assumed to each include a coil and are explained as alignment between the pads, but more specifically, it can be defined as alignment between the primary coil (transmission coil or GA coil) and the secondary coil (reception coil or VA coil) built into the transmission pad (21) and the reception pad (11), respectively.

[0143] FIG. 5 is an equivalent circuit of a single-phase wireless power transfer (WPT) system according to one embodiment of the present invention.

[0144] The magnetic / inductive coupling or resonant structure formed between the primary coil and the secondary coil of various embodiments of the present invention can be equivalently expressed by the transformer of FIG. 5.

[0145] Referring to FIG. 5, a single-phase AC-DC rectifier circuit (210) for applying an AC signal to the front end of the primary coil and a SPWM (sinusoidal pulse width modulation) inverter (220) are illustrated.

[0146] Also referring to FIG. 5, a rectifier (110) for transmitting power from the secondary coil to the load / battery and a charger (120) are shown.

[0147] A wireless power transmission device according to one embodiment of the present invention may include a power transmission circuit. The power transmission circuit illustrated in FIG. 5 may include, as a technical feature, a structure including a single-phase AC-DC rectifier circuit (210) and an SPWM inverter (220) on the primary coil side.

[0148] The power transmission circuit of FIG. 5 according to one embodiment of the present invention may include as technical features a single-phase AC-DC rectifier circuit (210) for transmitting power to the primary coil side, and a PI control structure based on a measurement value on the single-phase AD-DC rectifier circuit (210) for controlling the SPWM inverter (220).

[0149] The SPWM inverter (220) can receive the output of the single-phase AC-DC rectifier (210), generate an AC signal, and transmit the AC signal as an output to the primary coil.

[0150] An AC signal rectified by the operation of the rectifier (110) and charger (120) can be applied to the battery to charge the battery.

[0151] FIG. 6 is a conceptual cross-sectional view and an elevation view of a wireless power transmission pad (21) according to one embodiment of the present invention.

[0152] Referring to FIG. 6, a transmitting coil (21d) included in a transmitting pad (21) in a device performing wireless power transmission by a single-phase operation such as that of FIG. 5 is illustrated. The transmitting pad (21) of FIG. 6 can provide a single-phase operation mode. In addition, by using a receiving pad (11) including a receiving coil (not illustrated) having a shape corresponding to that of the transmitting pad (21) of FIG. 6, the receiving pad (11) can receive wireless power by a single-phase operation mode. Since the coil and hardware configuration for the single-phase operation mode of the receiving pad (11) can be easily implemented by those skilled in the art by modifying FIG. 6, a detailed description thereof will be omitted.

[0153] Referring to FIG. 6, the transmission pad (21) may include an outer case (21a) forming an outer shape, an aluminum shield (21b) installed in a flat shape inside the outer case (21a), a flat ferrite (21c) installed on top of the aluminum shield, and a transmission coil (21d) installed on top of the flat ferrite (21c). Here, the upper part may mean above the ground based on the ground on which the transmission pad (21) is installed.

[0154] Here, ferrite, the material used in the flat ferrite (21c), is a magnetic substance containing iron oxide, which can play an auxiliary role in transmitting and receiving wireless power by reducing magnetic resistance and assisting the flow of magnetic flux.

[0155] Figure 7 is a conceptual diagram illustrating a wireless power receiving device according to one embodiment of the present invention. In Figure 7, each block in the drawing represents a functional relationship or flow, and the connecting lines between blocks do not necessarily indicate an electrical connection or signal transmission path.

[0156] As illustrated in FIG. 7, a wireless power receiver (PRD) according to one embodiment of the present invention can receive wireless power from a wireless power transmitter (PTD) in a single-phase mode or a three-phase mode by magnetic induction. To this end, a mutual inductance (M) is formed between the transmitter and receiver due to magnetic coupling.

[0157] The above wireless power receiver (PRD) may include a receiving coil unit (400), a compensation circuit (500), a control unit (520), a rectifier unit (600), and a load unit (700).

[0158] The above-described receiving coil unit (400) may include an inductive element that receives a magnetic field generated from a wireless power transmitter (PTD), and may include one or three coils. Each coil is activated according to a single-phase or three-phase mode.

[0159] The above compensation circuit (500) is configured based on an LCC resonance topology (Inductor-Capacitor-Capacitor resonance topology) and includes a three-phase coupled inductor (510). The compensation circuit (500) may be provided to maintain the resonance condition of wirelessly received power.

[0160] In addition, the three-phase inductor combination (510) can maintain resonance conditions by compensating for equivalent inductance and reactance that change according to the transition between single-phase mode and three-phase mode.

[0161] The control unit (520) can detect the number of phases or the current distribution between phases of the wirelessly received power, thereby detecting a transition in the operating mode between single-phase mode and three-phase mode. That is, the control unit (520) can determine the operating mode (single-phase or three-phase) and control the components of the compensation circuit accordingly so as to maintain the resonance condition in real time.

[0162] The control unit (520) may also perform CC or CV mode switching, described later, based on information determined through phase detection or current analysis. Meanwhile, the resonance condition refers to a state in which the transmitting circuit and the receiving circuit are adjusted to operate at the same resonant frequency, thereby increasing power transfer efficiency by reducing power loss and increasing charging efficiency. For example, the resonance condition may include a zero phase angle (ZPA) condition.

[0163] The above rectifier (600) may include a circuit that rectifies the received AC power into DC power and converts the voltage level as needed to stabilize the final output voltage.

[0164] The above load unit (700) is a final load to which power is supplied, and may include, for example, a battery, a driving motor, an electronic device, etc.

[0165] A wireless power transmitter (PTD) is a corresponding component of the wireless power receiver (PRD), and may include, for example, a fixed charging pad or charging station, and may operate in cooperation with the wireless power receiver (PRD) through communication or position alignment functions as described in FIG. 1.

[0166] For example, the wireless power receiver (PRD) may be a component on the mobility or rechargeable device side, and may be an electric vehicle (10) as shown in FIG. 1 or a component included therein.

[0167] According to the above-described configuration, a three-phase inductor combination can be applied to satisfy the LCC compensation condition while maintaining the same receiver circuit structure even in a switching situation between single-phase and three-phase modes, and mode discrimination and control functions can be supplemented to realize flexible wireless power reception.

[0168] Fig. 8 is a circuit diagram showing an embodiment of a specific configuration of the wireless power receiving device illustrated in Fig. 7.

[0169] As illustrated in FIG. 8, the compensation circuit (500) is configured according to an LCC resonant topology and includes three branch circuits through which currents of different phases flow, and the three-phase inductor assembly (510) of the compensation circuit (500) includes a first inductor (IN1), a second inductor (IN2), and a third inductor (IN3) through which currents of different phases flow, respectively.

[0170] The above branch circuits may include a first branch, a second branch, and a third branch.

[0171] The above first quarter is L VA , C f2A , C P2A , L in2AIt is composed of, and the second branch is L VB , C f2B , C P2B , L in2B It is composed of, and the third quarter is L VC , C f2C , C P2C , L in2C It can be composed of including.

[0172] Here L in2A , L in2B , L in2C correspond to the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) included in the three-phase inductor assembly (510), respectively. The first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) are wound on an inductor core, and can compensate for reactance and inductance changes according to mode changes by mutual induction flux.

[0173] Specifically, the three-phase inductor assembly (510) may include an inductor core around which the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) are wound.

[0174] FIG. 9 is a perspective view illustrating one embodiment of a three-phase inductor combination of the circuit diagram illustrated in FIG. 8.

[0175] As illustrated in FIGS. 8 and 9, the three-phase inductor assembly (510a) according to the present embodiment includes a first inductor (IN1), a second inductor (IN2), and a third inductor (IN3) through which currents of different phases flow, a central leg (CLa) in which a central magnetic flux path is formed, and three outer legs (OLa) in which outer magnetic flux paths are formed.

[0176] The first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) can be wound on at least one of the intermediate group (CLa) and the three outer groups (OLa), and the central flux path and the outer flux path can be formed by the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3). For example, depending on the arrangement of the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3), the central flux path and the outer flux path can induce one another, or can influence each other and be induced simultaneously.

[0177] In Fig. 9, the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) can be wound on the three outer groups (Ola), respectively.

[0178] Structurally, in FIG. 9, the three-phase inductor assembly (510a) has a Y-shaped shape. The intermediate leg (CLa) forms a central magnetic flux path and can be radially branched into three outer legs (OLa). The outer legs (OLa) can be independently wound with the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3).

[0179] In one embodiment, the intermediate group (CLa) and the outer group (OLa) may provide a magnetic flux path in which each magnetic flux formed in the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) passes through the intermediate group (CLa) to form a closed loop to at least one of the outer groups (OLa).

[0180] When the above three-phase inductor combination (510a) has the structure as described above, each inductor (IN1, IN2, IN3) operates in an individual path without magnetic interference, while sharing a path in which magnetic flux is integrated through the intermediate stage (Ola), thereby maintaining a stable resonance condition when switching the operation mode.

[0181] FIG. 10 is a perspective view illustrating another embodiment of the three-phase inductor combination of the circuit diagram illustrated in FIG. 8.

[0182] As illustrated in FIGS. 8 and 10, the three-phase inductor assembly (510b) according to the present embodiment includes a first inductor (IN1), a second inductor (IN2), and a third inductor (IN3) through which currents of different phases flow, a central leg (CLb) in which a central magnetic flux path is formed, and three outer legs (OLb) in which outer magnetic flux paths are formed.

[0183] In Fig. 10, the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) can be alternately wound on the intermediate group (OLb).

[0184] Structurally, in FIG. 10, the three-phase inductor assembly (510a) has a cylindrical shape. The intermediate leg (CLb) is located at the center of the cylinder and serves as a central path for magnetic flux, and three outer legs (OLb) are arranged on the outside of the cylinder to form branch paths for magnetic flux. The intermediate legs (OLb) can be alternately wound with the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3).

[0185] When the above three-phase inductor combination (510b) has the structure as described above, each of the inductors (IN1, IN2, IN3) is alternately wound on the intermediate leg (OLb), so that magnetic flux interference can be minimized and resonance characteristics can be precisely controlled, and stability can be increased even in a high-frequency wireless power transmission environment.

[0186] FIG. 11 is a perspective view illustrating another embodiment of the three-phase inductor combination of the circuit diagram illustrated in FIG. 8.

[0187] As illustrated in FIGS. 8 and 11, the three-phase inductor assembly (510c) according to the present embodiment includes a first inductor (IN1), a second inductor (IN2), and a third inductor (IN3) through which currents of different phases flow, a central leg (CLc) in which a central magnetic flux path is formed, and three outer legs (OLc) in which outer magnetic flux paths are formed.

[0188] In Fig. 11, the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) are each wound on the three outer groups (OLc) and can be alternately wound on the middle group (CLc).

[0189] Structurally, in Fig. 11, the three-phase inductor assembly (510a) is a hybrid structure that additionally combines the winding method of Fig. 10 with the Y-shaped structure of Fig. 9. The geometric structures of the intermediate group (CLc) and the outer group (OLc) are similar to Fig. 9, but the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) are each wound on the outer groups (OLc), and can also be alternately wound on the intermediate group (CLc).

[0190] When the above three-phase inductor combination (510c) has the structure as described above, the interaction flux between each phase can be controlled more precisely, while the maintenance of resonance conditions and conversion efficiency can be further improved, and the reactance balance can be automatically adjusted even when switching between single-phase and three-phase modes.

[0191] The three-phase inductor combinations (510a, 510b, 510c) having the above-described configuration can autonomously compensate for resonance conditions under an LCC resonance topology in preparation for situations where equivalent inductance and reactance may change according to changes in operation between single-phase mode and three-phase mode, thereby maintaining the operational stability and energy transfer efficiency of the wireless power receiver (PRD) despite mode switching of the wireless power transmitter (PTD).

[0192] Meanwhile, it goes without saying that the shape and winding arrangement structure of the three-phase inductor combinations (510a, 510b, 510c) can be formed in various forms other than those shown in FIGS. 9 to 11.

[0193] Fig. 12 is an equivalent circuit diagram of the three-phase inductor combination of Fig. 11. Fig. 12 is a mathematical and circuit model of an actual magnetic coupling structure, in which mutual inductance (M) and self-inductance (L) are specifically expressed.

[0194] Fig. 12 specifically illustrates how the internal structure of the three-phase inductor assembly (510c) operates from a circuit perspective and how magnetic coupling is formed between each phase. The circuit diagram of Fig. 12 can be designed to respond to changes in resonance characteristics due to current distribution changes during single-phase / three-phase switching, and can be designed to perform high-efficiency wireless power reception.

[0195] As shown in Fig. 12, the winding structure of each of the first inductor (IN1), the second inductor (IN2), and the third inductor (IN3) is such that the first inductor (IN1) is L 2Ap , M 2AB , M 2AC is expressed as , and the second inductor (IN2) is L 2Bp , M 2BC , M 2BA is expressed as , and the third inductor (IN3) is L 2Cp , M2CB , M 2CA is expressed as

[0196] Here, each L denotes the self-inductance directly wound on each inductor, and M denotes the mutual inductance.

[0197] The above intermediate legs (CLc) form a central flux path and form a common flux flow between the three phases, and the outer legs (OLc) can form an outer flux path exclusive to each phase.

[0198] In Fig. 12, M 2AB , M 2BC , M 2CA The back represents the mutual coupling between phases, and these mutual inductances change their coupling characteristics due to the magnetic flux changes caused by different phase currents when the operating mode switches from single-phase to three-phase. Accordingly, compensation for the change in equivalent reactance can be made by appropriately designing the coupling inductance so that the resonance conditions for each phase are maintained under the LCC resonant topology.

[0199] Meanwhile, in the above-described embodiments, the number of turns wound on the intermediate leg (CL) and the number of turns wound on the outer leg (OL) are determined according to a turns ratio set in advance, and the turns ratio can be set so that the equivalent inductance satisfies the resonance condition in a single-phase or three-phase operation mode.

[0200] Fig. 13 is a circuit diagram illustrating an example of operation in a constant current mode based on the operating mode of power received by the wireless power receiver of Fig. 7. Fig. 13 illustrates a circuit that operates in a constant current (CC) mode when the wireless power receiver receives three-phase wireless power.

[0201] The receiving circuit includes a CC resonant network and a ZPA adjustment section.

[0202] The above CC resonant network is a structure that receives power through resonance, and includes a primary-side coupled inductor (M' 3p ), series inductor (L VM_3P ), series capacitor (C f2M ), parallel capacitor (C p2M ), which can form resonance and increase power transmission efficiency.

[0203] The above ZPA adjustment unit (ZPA Adjustment) is a compensation inductor (L) to satisfy the zero phase angle (ZPA) condition. in2M ) can be used to adjust the phase difference according to single-phase / three-phase conversion.

[0204] Accordingly, the load (R batt_phase ) is the phase current (i ab_3p ) as a flowing output load, which can induce a constant current charge.

[0205] A configuration like the above can be utilized when a three-phase input is input.

[0206] Fig. 14 is a circuit diagram illustrating an example of operation in a constant voltage mode based on the operating mode of power received by the wireless power receiver of Fig. 7. Fig. 14 illustrates a circuit that operates in a constant voltage (CV) mode when the wireless power receiver (PRD) receives single-phase wireless power.

[0207] The receiving circuit includes a CC resonant network and a CV resonant network.

[0208] The above CC resonant network is a structure that receives power through resonance, similar to Fig. 13, and has a primary-side coupled inductor (M' sp ), series inductor (L VM_SP ), series capacitor (C f2M ), parallel capacitor (Cp2M1 ), which can form resonance and increase power transmission efficiency.

[0209] The above CV resonant network is a parallel capacitor (C p2M2 ) and inductor for power compensation (L in2M ) to form a CV resonant network, and can operate so that the voltage is kept constant.

[0210] Accordingly, the load (R batt_phase ) is the load voltage (U ab_sp ) can be controlled to remain constant.

[0211] A configuration like the above can be utilized when a single-phase input is input.

[0212] Therefore, in the circuit according to FIGS. 13 and 14, reactance compensation may be possible by changing the compensation structure according to the operation in single-phase mode and three-phase mode, and the CC mode and CV mode may be defined differently according to the design of the receiving pad and / or the three-phase inductor combination.

[0213] FIG. 15 and FIG. 16 are circuit diagrams showing other embodiments of the specific configuration of the wireless power receiving device illustrated in FIG. 7.

[0214] As illustrated in FIG. 15, the wireless power receiver (PRD) includes an inductor assembly (510a) included in the compensation circuit (500) illustrated in FIG. 7, and three inductors (IN1a, IN2a, IN3a) can be wound around the three-phase inductor assembly (510a). The three-phase inductor assembly (510a) around which the inductors (IN1a, IN2a, IN3a) are wound can be formed similarly to the embodiments illustrated in FIGS. 9, 10, and 11.

[0215] The inductors (IN1a, IN2a, IN3a) of the above inductor combination (510a) are the first compensation inductor (L coup_A), second compensation inductor (L coup_B ), third compensation inductor ( Lcoup_C ) can correspond to. Each compensation inductor is connected in series with the current induced from the receiving pad or receiving coil section, and plays a role in compensating for the reactance change due to the change in pad inductance.

[0216] As illustrated in FIG. 16, the wireless power receiver (PRD) includes an inductor assembly (510b) included in the compensation circuit (500) illustrated in FIG. 7, and three inductors (IN1b, IN2b, IN3b) can be wound around the three-phase inductor assembly (510b). The three-phase inductor assembly (510b) around which the inductors (IN1b, IN2b, IN3b) are wound can be formed similarly to the embodiments illustrated in FIGS. 9, 10, and 11.

[0217] The inductors (IN1b, IN2b, IN3b) of the above inductor combination (510b) are first compensation inductors (L coup_A ), second compensation inductor (L coup_B ), third compensation inductor ( Lcoup_C ) can be corresponded to. Each compensation inductor has a separate compensation capacitor (C s2A , C s2B , C s2C ) are connected in series, which helps to maintain the overall resonance condition even when switching between single-phase mode and three-phase mode operation.

[0218] As described above, when utilizing a three-phase inductor combination (510a, 510b), the inductance variation can be directly compensated for by adding a three-phase inductor in series to the receiving pad or receiving coil section.

[0219] When operating in single-phase mode, the equivalent inductance of the receiving pad increases and the component of the three-phase inductor assembly (510a, 510b) decreases, and when operating in three-phase mode, the equivalent inductance of the receiving pad decreases and the component of the three-phase inductor assembly (510a, 510b) may increase.

[0220] At this time, by appropriately selecting the number of turns of the three-phase inductor assembly (510a, 510b), the total inductance can be designed to be the same regardless of the operation in single-phase mode and three-phase mode.

[0221] Fig. 17 is a flowchart illustrating a power compensation method for wireless charging according to one embodiment of the present invention.

[0222] As illustrated in Fig. 17, in a power compensation method for wireless charging that compensates for power received by a wireless power receiver including a compensation circuit configured based on an LCC resonance topology (Inductor-Capacitor-Capacitor resonance topology) and a control unit that controls the compensation circuit, first, in the control unit, the number of phases of power received wirelessly or the distribution of current between phases is detected to determine the current operation mode among single-phase mode or three-phase mode (S110).

[0223] Next, in the control unit, a three-phase coupled inductor including three outer legs in which an outer magnetic flux path is formed by a first inductor, a second inductor, and a third inductor, and a central leg in which a central magnetic flux path is formed by the first inductor, the second inductor, and the third inductor is controlled to compensate for equivalent inductance and reactance according to the current operation mode (S120).

[0224] The configuration of the compensation circuit related to this follows the embodiments illustrated in FIGS. 8 to 16 above, and a detailed description thereof will be omitted.

[0225] FIG. 18 is a block diagram illustrating a generalized configuration of hardware that controls a sequence for wireless power transmission included in a wireless power receiving device of the present invention or related to a wireless power receiving device.

[0226] For convenience of explanation, the hardware that controls the sequence for wireless power transmission may be referred to as a controller (1000).

[0227] The controller (1000) may be placed on the electric vehicle (10) side, on the electric vehicle power supply equipment (EVSE) (20) side, or on the transmission pad (21) side.

[0228] The controller (1000) may include at least one processor (1100), a memory (1200) storing at least one command for executing the above-described operation through the processor (1100), and a communication interface (1300) connected to a network and performing communication. The controller (1000) for wireless power transmission may further include a storage device (1400) capable of storing at least one command for executing the above-described operation or data generated during the execution process. The controller (1000) for wireless power transmission may further include an input interface (1500) and an output interface (1600) for interaction with a user. Each component included in the controller (1000) for wireless power transmission may be connected by a system bus (1700) and may communicate with each other.

[0229] A controller (1000) or computing system according to one embodiment of the present invention may include at least one processor (1100) and a memory (1200) that stores instructions that instruct the at least one processor (1100) to perform at least one step. At least some steps of a method according to one embodiment of the present invention may be performed by the at least one processor (1100) loading and executing instructions from the memory (1200).

[0230] The processor (1100) may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed.

[0231] Each of the memory (1200) and the storage device (1400) may be configured with at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory (1200) may be configured with at least one of a read-only memory (ROM) and a random access memory (RAM).

[0232] Here, at least one command may include at least one of a sequence that can mutually identify at least one of an electric vehicle (10), an electric vehicle power supply equipment (EVSE) (20), and a transmission pad (21), a sequence for wireless communication association between at least one or two of the electric vehicle (10), an electric vehicle power supply equipment (EVSE) (20), and a transmission pad (21), a sequence for performing alignment and / or pairing by mutual positioning, and a sequence for allowing application of an AC signal so that power is transmitted after alignment and / or pairing.

[0233] Additionally, the controller (1000) may include a communication interface (1300) that performs communication via a wireless network.

[0234] Additionally, the controller (1000) may further include a storage device (1400), an input interface (1500), an output interface (1600), etc.

[0235] Additionally, each component included in the controller (1000) can be connected to each other by a bus (1700) and communicate with each other.

[0236] Examples of the controller (1000) of the present invention may include a desktop computer, a laptop computer, a notebook, a smart phone, a tablet PC, a mobile phone, a smart watch, a smart glass, an e-book reader, a portable multimedia player (PMP), a portable game console, a navigation device, a digital camera, a digital multimedia broadcasting (DMB) player, a digital audio recorder, a digital audio player, a digital video recorder, a digital video player, a PDA (Personal Digital Assistant), etc. The operation of the method according to an embodiment of the present invention can be implemented as a computer-readable program or code on a computer-readable recording medium. The computer-readable recording medium includes all types of recording devices that store information that can be read by a computer system. Additionally, computer-readable recording media can be distributed across network-connected computer systems so that computer-readable programs or codes can be stored and executed in a distributed manner.

[0237] Additionally, the computer-readable recording medium may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. The program instructions may include not only machine language codes produced by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc.

[0238] While some aspects of the present invention have been described in the context of a device, they may also represent a description of a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described as a corresponding block or item or a feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, at least one or more of the most important method steps may be performed by such a device.

[0239] In embodiments, a programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described herein. In embodiments, the field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described herein. In general, the methods are preferably performed by some hardware device.

[0240] According to embodiments of the present disclosure, problems such as system instability, increase in reactive power, and decrease in efficiency that may occur due to changes in equivalent inductance of pads due to mode switching between single-phase and three-phase wireless charging methods can be effectively resolved.

[0241] In addition, by actively responding to changes in reactance according to the operating mode in this way, the wireless power receiver can secure interoperability for various transmission environments and provide stable charging performance without a decrease in power transmission efficiency or inverter protection issues.

[0242] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

Claims

1. A wireless power receiving device that receives power wirelessly in a single-phase mode or a three-phase mode, It is configured according to the LCC resonance topology (Inductor-Capacitor-Capacitor resonance topology) and includes a compensation circuit including a three-phase coupled inductor. The above three-phase inductor combination is, A first inductor, a second inductor, and a third inductor, each of which carries currents of different phases; Three outer legs in which an outer magnetic flux path is formed by the first inductor, the second inductor, and the third inductor; and A central leg including a central flux path formed by the first inductor, the second inductor, and the third inductor, Wireless power receiver.

2. In claim 1, The above three-phase inductor combination maintains the resonance condition by compensating for the equivalent inductance and reactance that change according to the transition between the single-phase mode and the three-phase mode. Wireless power receiver.

3. In claim 1, The number of turns wound on the above intermediate group and the number of turns wound on the outer group are determined according to a preset turns ratio, and the turns ratio is set so that the equivalent inductance satisfies the resonance condition in a single-phase or three-phase operation mode. Wireless power receiver.

4. In claim 1, The first inductor, the second inductor and the third inductor are each wound on the three outer groups. Wireless power receiver.

5. In claim 1, The first inductor, the second inductor and the third inductor are wound alternately on the intermediate group. Wireless power receiver.

6. In claim 1, The first inductor, the second inductor and the third inductor are each wound on the three outer groups and are alternately wound on the middle group. Wireless power receiver.

7. In claim 1, The above intermediate and outer groups provide a magnetic flux path in which each magnetic flux formed in the first inductor, the second inductor and the third inductor passes through the intermediate group and forms a closed loop with at least one of the outer groups. Wireless power receiver.

8. In claim 1, Further comprising a control unit for detecting the number of phases or the current distribution between phases of the power wirelessly received, thereby detecting the switching of the operating mode between the single-phase mode and the three-phase mode. Wireless power receiver.

9. In claim 1, The above compensation circuit is controlled to operate in either a constant current (CC) mode or a constant voltage (CV) mode based on the operating mode of the power received wirelessly. Wireless power receiver.

10. In claim 1, The above compensation circuit is controlled to operate in a constant current (CC) mode based on the fact that the power received wirelessly is in a three-phase mode. Wireless power receiver.

11. In claim 1, The above compensation circuit is controlled to operate in a constant voltage (CV) mode based on the fact that the power received wirelessly is in single-phase mode. Wireless power receiver.

12. A compensation circuit for a wireless power receiving device that wirelessly receives power in a single-phase mode or a three-phase mode, It is configured according to the LCC resonant topology (Inductor-Capacitor-Capacitor resonance topology) and includes a three-phase coupled inductor. The above three-phase inductor combination is, A first inductor, a second inductor, and a third inductor, each of which carries currents of different phases; Three outer legs in which an outer magnetic flux path is formed by the first inductor, the second inductor, and the third inductor; and A central leg including a central flux path formed by the first inductor, the second inductor, and the third inductor, Compensation circuit of a wireless power receiver.

13. In claim 12, The first inductor, the second inductor and the third inductor are each wound on the three outer groups. Compensation circuit of a wireless power receiver.

14. In claim 12, The first inductor, the second inductor and the third inductor are wound alternately on the intermediate group. Compensation circuit of a wireless power receiver.

15. In claim 12, The first inductor, the second inductor and the third inductor are each wound on the three outer groups and are alternately wound on the middle group. Compensation circuit of a wireless power receiver.

16. A power compensation method for wireless charging that compensates for power received by a wireless power receiving device including a compensation circuit configured based on an LCC resonant topology and a control unit that controls the compensation circuit, In the above control unit, a step of detecting the number of phases of power received wirelessly or the distribution of current between phases to determine the current operating mode among single-phase mode or three-phase mode; and In the above control unit, a step of controlling to compensate for equivalent inductance and reactance according to the current operation mode through a three-phase inductor combination including three outer legs in which an outer magnetic flux path is formed by a first inductor, a second inductor, and a third inductor, and a central leg in which a central magnetic flux path is formed by the first inductor, the second inductor, and the third inductor, Power compensation method for wireless charging.

17. In claim 16, The step of controlling to compensate for the above equivalent inductance and reactance is: Based on the current operation mode, including a step of switching between a constant current (CC) mode and a constant voltage (CV) mode, Power compensation method for wireless charging.

18. In claim 16, The step of controlling to compensate for the above equivalent inductance and reactance is: Including a step of controlling to operate in a constant current (CC) mode based on the fact that the power received wirelessly is in a three-phase mode. Power compensation method for wireless charging.

19. In claim 16, The step of controlling to compensate for the above equivalent inductance and reactance is: Including a step of controlling to operate in a constant voltage (CV) mode based on the fact that the power received wirelessly is in single-phase mode. Power compensation method for wireless charging.

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