Power transmission and reception device for performing bidirectional power transfer and bidirectional power transfer control method

Abstract

This bidirectional wireless charging system includes a supply-side power circuit and an EV-side power circuit. The supply-side power circuit includes at least one switching-controlled capacitor (SCC). The EV-side power circuit is connected to the supply-side power circuit via an inductive coupler. The bidirectional wireless charging system can switch between a constant-current (CC) mode and a constant-voltage (CV) mode by using a switch of the switching-controlled capacitor during vehicle-to-grid (V2G) power transfer in which wireless charging is performed from the EV-side power circuit to the supply-side power circuit.

Description

Power transmission and reception device performing two-way power transmission and two-way power transmission control method

[0001] The present disclosure relates to a power transmission and reception device that performs bidirectional power transmission and a bidirectional power transmission control method, and more particularly, to a power transmission and reception device that performs bidirectional power transmission using a switching control capacitor and a phase shift, and a bidirectional power transmission control method.

[0002] The material described in this section merely provides background information for the present embodiment and does not constitute prior art.

[0003] Electric vehicles (EVs) currently under development use battery power to drive a motor, and thus have the advantages of producing fewer air pollutants such as exhaust gases and noise, being less prone to breakdowns, having a longer lifespan, and being easier to drive than conventional gasoline engine vehicles.

[0004] Electric vehicles are categorized by their propulsion system into hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and electric vehicles (EVs). HEVs have an engine as their primary power source and a motor as an auxiliary power source. PHEVs have a motor as their primary power source and an engine that powers the vehicle when the battery is discharged. EVs have a motor but no engine.

[0005] An electric vehicle charging system can be fundamentally defined as a system that charges the batteries mounted on an electric vehicle using power from the commercial power grid or energy storage devices. These systems can take various forms depending on the type of electric vehicle. For example, an electric vehicle charging system may include a conductive charging system using cables or a contactless wireless power transfer system.

[0006] When charging an electric vehicle, a vehicle assembly (VA) mounted on the electric vehicle forms an inductive resonant coupling with a transmitting pad of a ground assembly (GA) located at a charging station or charging spot, and the battery of the electric vehicle can be charged using power transmitted from the ground assembly through the inductive resonant coupling.

[0007] In general, wireless power transfer (WPT) of electric vehicles is divided into a transmitter installed on the outside of the vehicle including a transmitter pad, and a receiver installed on the inside of the vehicle including a receiver pad.

[0008] The transmitter converts energy supplied from the power system into a high-frequency AC signal through a switching device and transmits it to the transmission pad.

[0009] A voltage is induced in the receiving pad by the time-varying magnetic field generated at the transmitting pad.

[0010] The power conversion circuit mounted on the receiver converts the power received through the receiving pad into a DC voltage and charges the high-voltage battery.

[0011] The current standard for wireless charging systems for EVs presented by the Automotive Technology Association only presents a single-phase wireless charging system, and unlike existing resonant converters, output control through switching frequency changes during operation is not possible.

[0012] Switching controlled capacitor (SCC) or variable inductor circuit used in single-phase wireless charging system is attached only for the purpose of adjusting according to the separation distance position of the receiving pad and the rated power value.

[0013] In addition, when the EV wireless charging system operates bidirectionally, an appropriate SCC control method for grid connection has not been presented.

[0014] The purpose of the present disclosure to solve the above problems is to provide a power transmission and reception device and a bidirectional power transmission control method that perform bidirectional power transmission capable of switching between constant current (CC) mode and constant voltage (CV) mode through the operation of a switching control capacitor during vehicle-to-grid (V2G) power transmission in the bidirectional operation of an EV wireless charging system.

[0015] In order to solve these problems, a first power transmission / reception device according to an exemplary embodiment of the present disclosure is a first power transmission / reception device for wirelessly transmitting power to a second power transmission / reception device and wirelessly receiving power from the second power transmission / reception device, the first power transmission / reception device including a first inductor, a first switching control capacitor (SCC), a second switching control capacitor (SCC), and a first control unit. The first inductor is coupled with a second inductor of the second power transmission / reception device for wireless power transmission / reception. The first SCC and the second SCC are each electrically connected to the first inductor. The first control unit controls the first SCC and the second SCC. When the first power transmission / reception device receives wireless power from the second power transmission / reception device, the first control unit controls the first SCC and the second SCC to switch between a constant current (CC) mode and a constant voltage (CV) mode.

[0016] As an example, the first power transmission / reception device may be on the charger side, and the second power transmission / reception device may be on the mobility or chargeable device side.

[0017] As an embodiment, the first power transmission and reception device may further include a first capacitor and a third inductor. The first capacitor may be disposed between one end of the first inductor and a first node. The third inductor may be disposed between the first node and a first terminal. At this time, the first SCC may be disposed between a second node between the other end of the first inductor and a second terminal and the second terminal. In addition, the second SCC may be disposed between the first node and the second node.

[0018] As an example, in the CC mode, the first control unit can control the switches of the first SCC and the second SCC to be turned on, and in the CV mode, the first control unit can control the switches of the first SCC and the second SCC to be turned off.

[0019] As an example, when the first power transmission / reception device transmits wireless power to the second power transmission / reception device, the first control unit can control the switch of the first SSC to be turned on and control the switch of the second SCC to be turned off.

[0020] As an example, the first power transmission / reception device may further include a first active bridge electrically connected to the first terminal and the second terminal.

[0021] According to an exemplary embodiment of the present invention, a second power transmission / reception device is a second power transmission / reception device for wirelessly transmitting power to a first power transmission / reception device and receiving power wirelessly from the first power transmission / reception device, and includes a second inductor, a third switching control capacitor (SCC), and a second control unit. The second inductor is coupled with the first inductor of the first power transmission / reception device for wireless power transmission / reception. The third SCC is electrically connected to the second inductor. The second control unit controls the third SCC. When the second power transmission / reception device transmits wireless power to the first power transmission / reception device, the second control unit controls the third SCC to switch between a constant current (CC) mode and a constant voltage (CV) mode.

[0022] As an example, the first power transmission / reception device may be on the charger side, and the second power transmission / reception device may be on the mobility or chargeable device side.

[0023] As an example, the second power transmission and reception device may further include a second capacitor, a fourth inductor, and a third capacitor. The second capacitor may be disposed between one end of the second inductor and a third node. The fourth inductor may be disposed between the third node and a third terminal. The third capacitor may be disposed between a fourth node between the fourth terminal and the other end of the second inductor. The third SCC may be connected in parallel with the second capacitor.

[0024] As an example, in the CC mode, the second control unit can control the switch of the third SCC to be turned off, and in the CV mode, the second control unit can control the switch of the third SCC to be turned on.

[0025] As an example, when the first power transmission / reception device transmits wireless power to the second power transmission / reception device, the second control unit can control the switch of the third SSC to be turned on.

[0026] As an example, the second power transmission and reception device may further include a second active bridge electrically connected to the third terminal and the fourth terminal.

[0027] A bidirectional power transmission control method according to an exemplary embodiment of the present invention is a bidirectional power transmission control method between a first power transmission / reception device including first and second switching control capacitors (SCC1, SCC2) and a second power transmission / reception device including a third switching control capacitor (SCC3), the method comprising: a step of sensing a state of charge (SoC) of a battery; a step of determining a constant current (CC) mode and a constant voltage (CV) mode according to the sensed state of charge of the battery; and a step of controlling switches of SCC1, SCC2, and SCC3 according to the determined mode.

[0028] As an example, the first power transmission / reception device may be on the charger side, and the second power transmission / reception device may be on the mobility or chargeable device side.

[0029] As an example, when the state of charge (SoC) of the battery is sensed and the SoC of the battery is below a set value, the mode may be determined as CV mode, and when the SoC of the battery is above the set value, the mode may be determined as CC mode.

[0030] As an example, when the second power transmission / reception device transmits wireless power to the first power transmission / reception device, in the CC mode, the second power transmission / reception device and the first power transmission / reception device may configure a VC resonant network, a first power factor improvement network, a CC resonant network, and a second power factor improvement network, and in the CV mode, the second power transmission / reception device and the first power transmission / reception device may configure a VC resonant network, a first power factor improvement network, a CC resonant network, and a CV resonant network.

[0031] As an example, when the first power transmission / reception device transmits wireless power to the second power transmission / reception device, the first power transmission / reception device and the second power transmission / reception device may configure a VC resonant network, a first power factor improvement network, a CC resonant network, and a second power factor improvement network.

[0032] When applying the embodiments of the present disclosure, in V2G (Vehicle to Grid) mode, a switching control capacitor (SCC) can be used to maintain a constant voltage range regardless of the state of charge (SoC) of the battery.

[0033] Figure 1 is a conceptual diagram illustrating a first embodiment of a communication system.

[0034] Figure 2 is a block diagram illustrating a first embodiment of a communication node constituting a communication system.

[0035] FIG. 3 is a circuit diagram illustrating a two-way wireless charging system according to an exemplary embodiment of the present invention.

[0036] Figure 4 is a circuit diagram illustrating the supply-side circuit block illustrated in Figure 3.

[0037] Fig. 5 is a circuit diagram showing the EV side circuit block illustrated in Fig. 3.

[0038] Fig. 6 is a circuit diagram showing a VC resonant network as a VC conversion.

[0039] Fig. 7 is a circuit diagram showing a CV resonant network as a CV converter.

[0040] Fig. 8 is a circuit diagram showing a CC resonance network as a CC conversion.

[0041] FIG. 9 is an equivalent circuit diagram illustrating the operation of the first power transmission / reception device and the second power transmission / reception device illustrated in FIG. 3 in a constant current (CC) mode when the first power transmission / reception device wirelessly transmits power to the second power transmission / reception device.

[0042] FIG. 10 is an equivalent circuit diagram illustrating the operation of the first power transmission / reception device and the second power transmission / reception device illustrated in FIG. 3 in a constant current (CC) mode when the second power transmission / reception device wirelessly transmits power to the first power transmission / reception device.

[0043] FIG. 11 is an equivalent circuit diagram illustrating the operation of the first power transmission / reception device and the second power transmission / reception device illustrated in FIG. 3 in a constant voltage (CV) mode when the second power transmission / reception device wirelessly transmits power to the first power transmission / reception device.

[0044] FIG. 12 is a flowchart illustrating a bidirectional power transmission control method according to an exemplary embodiment of the present disclosure.

[0045] FIG. 13 is a block diagram illustrating a generalized configuration of a generalized wireless power transmitting pad device, a wireless power receiving pad device, a wireless power transfer (WPT) system, or a computing system controlling them according to one embodiment of the present invention.

[0046] This disclosure may be subject to various modifications and various embodiments. Specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the disclosure to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the disclosure.

[0047] While terms such as "first" and "second" may be used to describe various components, 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 disclosure, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component." The term "and / or" may refer to a combination of multiple related items described herein or to any of multiple related items described herein.

[0048] In the present disclosure, “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.” Additionally, in the present disclosure, “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.”

[0049] In the present disclosure, (re)transmission may mean “transmission,” “retransmission,” or “transmission and retransmission,” (re)setting may mean “setting,” “resetting,” or “setting and resetting,” (re)connection may mean “connection,” “reconnection,” or “connection and reconnection,” and (re)connection may mean “connection,” “reconnection,” or “connection and reconnection.”

[0050] 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.

[0051] The terminology used in this disclosure is only used to describe specific embodiments and is not intended to limit the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, it should be understood that the terms "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0052] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this disclosure 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 shall not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0053] Hereinafter, preferred embodiments of the present disclosure will be described in more detail with reference to the attached drawings. In order to facilitate an overall understanding in describing the present disclosure, the same reference numerals will be used for identical components in the drawings, and redundant descriptions of identical components will be omitted. In addition to the embodiments explicitly described in the present disclosure, operations may be performed according to combinations of embodiments, extensions of embodiments, and / or modifications of embodiments. The performance of some operations may be omitted, and the order of operation may be changed.

[0054] The operations of the method according to the present disclosure can be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes any type of recording device that stores information readable by a computer system. Furthermore, a computer-readable recording medium can be distributed across network-connected computer systems, allowing the computer-readable program or code to be stored and executed in a distributed manner.

[0055] 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.

[0056] While some aspects of the present disclosure 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 significant method steps may be performed by such a device.

[0057] 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 in the present disclosure. The field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described in the present disclosure. In general, the methods are preferably performed by some hardware device.

[0058] Some terms used in this specification are defined as follows:

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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).

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] An inductive coupler is a transformer that is formed by a primary device and a secondary device and transmits power through electrical isolation.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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).

[0083] 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.

[0084] Ambient temperature may refer to the ground level temperature measured in the atmosphere of a target subsystem that is not directly exposed to sunlight.

[0085] Vehicle ground clearance can refer to the vertical distance between the road or pavement and the lowest part of the vehicle's floor pan.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] Hazardous live component may refer to a live component that may, under certain conditions, cause a hazardous electric shock.

[0091] Live component may refer to any conductor or conductive part that is electrically active in its basic use.

[0092] Direct contact can refer to contact between living beings, such as humans.

[0093] Indirect contact may refer to contact with exposed, conductive, live components due to an insulation failure (see IEC 61140).

[0094] 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.

[0095] 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.

[0096] Correlation / Association may include the process of establishing a relationship between two peer communication entities.

[0097] 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.

[0098] High-level communication can handle all information beyond what command and control communication can handle. High-level communication data links can use, but are not limited to, power line communication (PLC).

[0099] 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.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] 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.

[0105] 'Smart Grid' can refer to a system implemented in which power plants, power generation units, and energy storage systems are all connected in an intelligent manner through network facilities and can exchange messages based on information and communication technology.

[0106] 'OEM (Original Equipment Manufacturer)' can refer to the top-level certification authority (CA) that issues OEM root certificates as a server operated by an electric vehicle manufacturer.

[0107] A 'charging station' may refer to a facility that includes one or more electric vehicle power supply equipment (EVSE), smart meters, and other technical equipment required to charge an electric vehicle (EV).

[0108] 'EV Supply Equipment (EVSE) is a device that forms part of a charging station that supplies energy to electric vehicles via outlets, and can refer to a device that is connected to a smart meter to measure energy.

[0109] A 'charging station (CS)' may refer to a facility that includes one or more EV power supply devices and actually performs charging for EVs.

[0110] 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 including at least one ground assembly, such as a home, office, public place, road, or parking lot.

[0111] 'Charging station operator (CSO)' may refer to an entity that manages electricity to provide requested energy transmission services, and may be a term with the same concept as charging point operator (CPO).

[0112] A 'Charge Service Provider (CSP)' can refer to an entity that manages and authenticates the credentials of EV users and provides billing and other value-added services to customers. It can be considered a special type of MO and can also be implemented in a form combined with an MO.

[0113] A 'Charge Point Operator (CPO)' may refer to a company or organization that has authority over the location of a charging station to allow physical access to the charging station, and may also refer to a communication node or entity that manages the charging station and authorizes and controls the charging process taking place at individual electric vehicle power supply equipment (EVSE) using information and communication technology.

[0114] A 'Mobility Operator (MO)' may refer to a legal entity that forms a contractual relationship with an end user or business regarding charging, as the legal basis for authorization and payment for charging at a charging station.

[0115] E-Mobility Provider (EMP), E-Mobility Service Provider (EMSP), and Mobility Service Provider (MSP) can be used in a similar sense to mobility operator.

[0116] Additionally, a 'mobility operator (MO)' may refer to a service provider that has a contractual relationship with EV owners regarding charging, authorization, and payment so that EV drivers can charge their EVs at charging stations.

[0117] A 'clearing house (CH)' is an entity that handles cooperation between MOs, CSPs, and CSOs, and can act as an intermediary to facilitate the approval, billing, and settlement procedures for EV charging service roaming, particularly between two settlement or clearing parties.

[0118] 'Roaming' can refer to the information exchange and related provisions and schemes that enable EV users to access charging services provided by multiple CSPs or CSOs belonging to multiple mobility networks using a single credential and contract.

[0119] A 'credential' is a physical or digital asset that represents the personal information of an EV or its owner. It may include a password, which is cryptographic information used to verify identity, a public key / private key pair used in a public key cryptographic algorithm, a public key certificate issued by a certification authority, and information related to a trusted root certification authority.

[0120] A 'certificate' can refer to an electronic document that binds a public key to an ID through a digital signature.

[0121] A 'service session' may refer to a set of services related to electric vehicle charging at a charging point, assigned to a customer over a given timeframe with a unique identifier.

[0122] Plug-and-Charge (PnC) can refer to a process in which authentication, authorization, load control, and payment are automatically performed without any further user interaction simply by plugging an electric vehicle into an electric vehicle power supply. Alternatively, PnC can also refer to an identification and authorization mode for such an automated process. PnC can be implemented by applying X.509 certificates, verifying signatures, and transmitting them.

[0123] 'Public Key Infrastructure (PKI)' can refer to a system for generating, storing, redistributing, and revoking digital signatures used to verify that a specific public key belongs to a specific person or entity.

[0124] An "External Identification Means (EIM)" can refer to any external means by which a driver can authenticate and authorize themselves for a charging session at a charging station. Examples include cash payments, prepaid cards, credit cards, debit cards, NFC, RFID, and SMS. EIM can be configured in conjunction with PnC for two authentication modes.

[0125] A "Sales Tariff" can refer to a feature that provides price information over time. Specifically, it can refer to an input provided by a mobility operator that allows the EV Communication Controller (EVCC) to calculate a charging schedule. A sales tariff can be intended to incentivize electric vehicles to charge a desired amount of electricity within a specific time slot. A use case related to a sales tariff could be pricing information for electricity provided by a mobility operator that authenticates a charging session with a valid contract. This contract can be authenticated by the driver or the car-sharing operator to which the vehicle belongs, using a contract certificate installed in the electric vehicle.

[0126] Additionally, the term "sales rate" can refer to a concept intended to encourage the use of renewable energy sources, such as solar panels or wind turbines, by providing incentives to electric vehicles that charge during predictable times, such as when charging with renewable energy sources. In some cases, the sales rate may include not only the price of electricity but also the time slot associated with that price.

[0127] A "secondary actor" can refer to any party involved in the charging process, other than an EVCC or SECC. A secondary actor can be involved in the charging process by providing information relevant to the charging process. Examples of secondary actors include charge point operators (CPOs) and mobility operators (MOs).

[0128] 'e-Mobility Account Identifier (eMAID)' may refer to a unique EV identifier that links a contract certificate to the EV owner's payment account.

[0129] An "E-Mobility Account ID (EMAID)" can refer to a single contractual certificate issued for each legal contract concluded between a mobility operator and a customer for electric vehicle charging. EMAID can allow for the pseudonymization of personal data and can be valid only for a limited period of time, such as the lifetime of the legal contract. Unlike a Vehicle Identification Number (VIN), EMAID may not allow for long-term evaluation of customer or vehicle data. EMAID can be introduced as a temporary identifier that can be assigned using different authentication methods for temporary, short-term single contracts, such as family vehicles or car-sharing contracts. Since one person can have an EMAID for each of multiple contracts, it can be used for purposes different from personal identification information.

[0130] In this disclosure, vehicle-to-grid (V2G) communication is defined in the ISO 15118 standard and can be designed to correspond to the 7-layer OSI. In other words, OSI (Open Systems Interconnection) can be "a conceptual model for standardizing the communication functions of a communication or computing system regardless of the internal structure and technology involved."

[0131] The ISO 15118 standard is designed to establish and implement charging and payment processes for electric vehicles. Another key feature is its ability to adopt and leverage various information and communication technologies. While it includes information and communication technology elements mapped to the seven layers of the OSI model, its primary purpose is to establish charging and payment processes for electric vehicles, so application-specific features are primarily addressed.

[0132] The V2G communication interface defined by the ISO 15118 standard can include digital, IP-based protocols. Communication between the electric vehicle (EV) and the electric vehicle power supply (EVSE), as well as between the electric vehicle power supply (EVCC) and the supply equipment communication controller (SECC), can be included within the V2G communication interface defined by the ISO 15118 standard.

[0133] The V2G communication interface and ISO 15118 standard may be intended to enable user-friendly mechanisms for authentication, authorization, and payment at charging stations without requiring separate user interaction.

[0134] Electric vehicles can be integrated into the smart grid to provide flexible load control and valuable grid services that accommodate diverse driver habits without compromising them. To avoid the need for additional grid components to supply power during peak demand due to highly variable load fluctuations, the energy from electric vehicles can be considered as an energy source within the smart grid. Furthermore, providing appropriate incentives for electric vehicles can be considered to promote the smart grid's long-term expansion of renewable energy.

[0135] The Vehicle-to-Grid Transfer Protocol (V2GTP) at Layer 5 of the OSI model can be fundamentally understood as a session wrapper for application-layer messages. These application-layer messages can be referred to as vehicle-to-grid (V2G) messages. The V2GTP protocol can include header and payload definitions that enable efficient identification and processing of V2G messages.

[0136] Autoconnect Charging Device or Automatic Charging Device (ACD) technology can be implemented based on the content specified in ISO / IEC 15118 Edition 2, ISO 15118-20 to perform at least part of the charging process by controlling a robot or automated device using wireless communication.

[0137] As examples of ACD technology, types such as ACD-U (Underbody), ACD-S (Sidearm), or ACD-P (Pantograph) have been proposed based on the direction in which the ACD equipment on the EVSE side approaches the electric vehicle and / or the location of the ACD equipment on the EVSE side with respect to the electric vehicle, and additional ACD types may be included in the future as wired / wireless charging technology expands.

[0138] The ACD charging communication method described below can be configured to define a new name space, change message parameters, change message sequences, and utilize a docking-undocking-pairing mechanism in ACD charging communication of ISO 15118 over WLAN. In addition, the ACD charging communication method can be configured to define VSE additional information parameters for ACD-U or ACD-S.

[0139] VSE (Vendor Specific Element) may refer to a data format that contains information about the type of EVSE available at the current location in ISO 15118-based communication.

[0140] 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.

[0141] Figure 1 is a conceptual diagram for explaining the concept of wireless power transmission for an electric vehicle to which one embodiment of the present invention is applied.

[0142] Wireless power transfer can be utilized to transfer power from a charging station to an electric vehicle (20) in order to charge the battery of the electric vehicle (20). Here, wireless power transfer, for example, magnetic field wireless power transfer (MF-WPT), can be defined as the transfer of energy through a magnetic field between an electric vehicle supply equipment (EVSE: Electric Vehicle Supply Equipment, 10) of a charging station and an electric vehicle (20) without a current flow through a galvanic connection by a conductor.

[0143] The EVSE (10) can receive power from a commercial power grid (2) or power backbone, and supply energy to the electric vehicle (20) through the transmission pad (13). The transmission pad (13) has a transmission coil. The electric vehicle (20) can include a reception pad (23) having a reception coil. The transmission coil in the transmission pad (13) can generate magnetic flux and supply magnetic energy to the electric vehicle (20) through the magnetic flux, or supply magnetic energy amplified by magnetic resonance to the electric vehicle (20). The charging station or EVSE (10) can be installed in various locations, such as a parking lot attached to the home of an electric vehicle (20) owner, a parking area for charging electric vehicles at a gas station, a parking area of ​​a shopping center or an office building, etc.

[0144] The EVSE (10) can communicate with an infrastructure management system or infrastructure server that manages the power grid (2) through wired or wireless communication. In addition, the EVSE (10) can also perform wireless communication with an electric vehicle (20). Here, the wireless communication may include a wireless local area network (WLAN) based on WiFi according to the IEEE 802.11 protocol. In addition, the wireless communication may further include P2PS communication using a low frequency (LF) magnetic field signal and / or a low power excitation (LPE) magnetic field signal. For example, the EVSE (10) and the electric vehicle (20) can perform processes such as pairing, positioning, identification, authentication, service authorization, and fee payment through WiFi-based communication, and can perform location alignment through P2PS communication. Furthermore, wireless communication between EVSE (10) and electric vehicle (20) may include one or more of various communication methods such as Bluetooth, Zigbee, and cellular.

[0145] An electric vehicle (20) is a vehicle (automobile) that can be driven by an electric motor using electric energy stored in a rechargeable energy storage device such as a battery (29) as a power source. An electric vehicle (20) may include a hybrid vehicle equipped with both an electric motor and a general internal combustion engine, and may also include not only automobiles but also motorcycles, carts, scooters, and electric bicycles.

[0146] The electric vehicle (20) may include a receiving pad (23) having a receiving coil for wirelessly receiving magnetic energy from the EVSE (10). The receiving coil in the receiving pad (23) receives magnetic energy from the transmitting coil of the transmitting pad (13) in the charging station (10), for example, through magnetic flux or magnetic resonance. Due to the magnetic energy received from the electric vehicle (20), an electromotive force is induced in the receiving coil of the receiving pad (23) and an induced current flows, and the induced current is rectified into a direct current and then charges the battery (29).

[0147]

[0148] Figure 2 is a block diagram of a wireless power transmission system according to one embodiment of the present invention. The wireless power transmission system includes an electric vehicle power supply unit (EVSE) 10 installed at a charging station and an EV device (20, hereinafter, "EV device" is used instead of "electric vehicle") such as an electric vehicle.

[0149] EVSE (10) includes a supply power circuit (SPC: Supply power circuit, 11), a supply equipment communication controller (SECC: Supply equipment communication controller, 14), and a P2PS communication interface (15).

[0150] The supply-side power circuit (11) can receive power from a power grid, form a magnetic flux from the power supply, and supply energy to the EV device (20) through magnetic resonance. The supply-side power circuit (11) can include a supply-side power electronic circuit (12) and a primary device, i.e., a transmission pad (13).

[0151] The supply-side power electronics circuit (12) receives single-phase AC power from the power grid and performs a grid interface function that changes the frequency and voltage level of the input voltage and current. In addition, the supply-side power electronics circuit (12) can perform power factor control, regulation, and filtering operations, and can perform safety measures such as shutdown as needed. In addition, the supply-side power electronics circuit (12) can cause resonance to occur between the transmission pad (13) and the EV device (20) so that high-power energy can be supplied to the EV device (20) through the transmission pad (13). Meanwhile, the supply-side power electronics circuit (12) can compensate for reactance variations for each vehicle and ensure impedance matching. For example, reactance may vary depending on not only vehicle-to-vehicle variations but also height differences and alignment conditions of the receiving pad (23), and reactance compensation can reduce stress on the transmission coil within the transmission pad (13) and reduce losses associated with high inverter current and harmonic generation. The supply-side power electronic circuit (12) can control the overall operation of the supply-side power circuit (11) including the transmission pad (13).

[0152] The transmission pad (13) has a transmission coil and generates a magnetic field from the supplied power, thereby enabling high-energy level magnetic energy to be transmitted to the EV device (20) through magnetic resonance.

[0153] The supply device communication controller (SECC, 14) is an upper layer controller and can communicate with the EV communication controller (EVCC, 24) in the EV device (20) via a wireless LAN based on, for example, WiFi. The SECC (14) and the EVCC (24) can perform application layer communication of the WPT system according to, for example, the ISO 15118-20 standard, and can perform processes such as pairing, positioning, identification, compatibility verification, authentication, service authorization, and fee payment. The physical layer and data link layer of the WLAN link can be configured to comply with, for example, the ISO 15118-8 standard. In addition, the SECC (14) can control the supply side power circuit (110) to ensure smooth and precise wireless power transmission from the EVSE (10) to the EV device (20). Furthermore, the SECC (14) can control the P2PS communication interface (15).

[0154] The P2PS communication interface (15) performs P2PS communication with the EV device (200) under the control of the SECC (14). In the present specification, including the claims, P2PS communication refers to communication for transmitting and receiving a signal for charging using a low frequency (LF) magnetic field signal and / or a low power magnetic field (LPE) signal. P2PS communication can be used for vehicle positioning and / or position alignment between a transmitting pad (13) and a receiving pad (23).

[0155] Meanwhile, the EV device (20) includes an EV power circuit (EVPC: EV power circuit, 21), an EV communication controller (EVCC, 24), and a P2PS communication interface (25).

[0156] The EV-side power circuit (21) receives magnetic energy in the form of magnetic flux variation from the supply-side power circuit (11) of the EVSE (10), converts the received magnetic energy into an induced current, and then rectifies the induced current into a direct current to charge the battery (see Fig. 1, 29) in the storage device (28). The EV-side power circuit (21) may include an EV-side power electronic circuit (22) and a secondary device, i.e., a receiving pad (23).

[0157] The receiving pad (23) has a receiving coil and can receive high-energy level magnetic energy supplied in a magnetic resonance state, for example, by capturing the magnetic flux variation induced from the transmitting pad (13).

[0158] The EV-side power electronics circuit (22) receives power from the transmission pad (13) through the reception pad (23) and changes the frequency and voltage level. In addition, the EV-side power electronics circuit (22) can rectify and filter the power received through the reception pad (23). The EV-side power electronics circuit (22) can perform regulation operations and, if necessary, perform safety measures such as shutdown. In addition, the EV-side power electronics circuit (22) can compensate for reactance fluctuations in the reception pad (23) and ensure impedance matching. The supply-side power electronics circuit (12) can control the overall operation of the supply-side power circuit (11) including the transmission pad (13).

[0159] The EV communication controller (EVCC, 24) is an upper layer controller and can communicate with the SECC (14) in the EVSE (10) via a wireless LAN based on, for example, WiFi. The EVCC (24) can perform application layer communication of the WPT system according to, for example, the ISO 15118-20 standard. The physical layer and data link layer of the WLAN link can be configured to comply with, for example, the ISO 15118-8 standard. In addition, the EVCC (24) can control the EV-side power circuit (21) to ensure smooth and precise power reception from the EVSE (10). Furthermore, the EVCC (24) can control the P2PS communication interface (25).

[0160] The P2PS communication interface (25) can perform P2PS communication with the EVSE (20) under the control of the EVCC (24). In the present specification, including the claims, P2PS communication refers to communication that transmits and receives a signal for charging using a low frequency (LF) magnetic field signal and / or a low power magnetic field (LPE) signal. P2PS communication can be used for vehicle positioning and / or position alignment between a transmitting pad (13) and a receiving pad (23).

[0161] According to one embodiment, the P2PS communication interface (15, 25) supports at least one type of P2PS interface among LF signals and LPE signals. Each type of P2PS interface may be a unidirectional P2PS interface. The LF signal is a digitally modulated magnetic field having a frequency belonging to the ultra-low frequency and low frequency (i.e., 3 kHz to 300 kHz, which are LF and VLF bands) among the radio bands specified by the International Telecommunication Union (ITU). In one embodiment, the LF signal may be transmitted by the P2PS communication interface (25) of the EV device (20) and received by the P2PS communication interface (15) of the EVSE (10). For this purpose, the P2PS communication interface (25) of the EV device (20) may be equipped with an LF transmitter, and the P2PS communication interface (15) of the EVSE (10) may be equipped with an LF receiver. Meanwhile, the LPE signal can be transmitted by the P2PS communication interface (15) of the EVSE (10) and received by the P2PS communication interface (25) of the EV device (20). To this end, the P2PS communication interface (15) of the EVSE (10) can be equipped with an LPE transmitter, and the P2PS communication interface (25) of the EV device (20) can be equipped with an LPE receiver.

[0162] In an exemplary embodiment of the present invention, the ground assembly (GA) may be used in the same sense as the transmission pad (13). The ground assembly or the transmission pad (13) essentially includes a primary device, i.e., a transmission coil. However, in a modified embodiment, the ground assembly and the transmission pad (13) may be used in different senses. In addition to the transmission coil, the ground assembly or the transmission pad (13) may additionally include at least a portion of an LPE transmitter and / or an LF receiver and / or a supply-side power electronics circuit (12).

[0163] The ground assembly or transmission pad (13) may be installed so as to protrude upward from the ground at the charging spot of the charging station and be at least partially exposed. In another example, the ground assembly or transmission pad (13) may be installed so that the upper surface thereof is an extension of the ground. In another example, the ground assembly or transmission pad (13) may be installed so as to be buried beneath the ground.

[0164] In an exemplary embodiment of the present invention, the vehicle assembly (VA) may be used in the same sense as the receiving pad (23). The vehicle assembly or the receiving pad (23) essentially includes a secondary device, i.e., a receiving coil. However, in modified embodiments, the vehicle assembly and the receiving pad (23) may be used in different senses. In addition to the receiving coil, the vehicle assembly or the receiving pad (23) may additionally include an LPE receiver and / or an LF transmitter and / or at least a portion of an EV-side power electronics circuit (22). The vehicle assembly or the receiving pad (23) may be installed on the lower part of the vehicle.

[0165]

[0166] FIG. 3 is a circuit diagram illustrating a two-way wireless charging system according to an exemplary embodiment of the present invention, FIG. 4 is a circuit diagram illustrating a supply-side circuit block illustrated in FIG. 3, and FIG. 5 is a circuit diagram illustrating an EV-side circuit block illustrated in FIG. 3.

[0167] Referring to FIG. 3, a first power transmission / reception device (113) according to an exemplary embodiment of the present disclosure wirelessly transmits power to a second power transmission / reception device (213) and wirelessly receives power from the second power transmission / reception device (213). For example, the first power transmission / reception device (113) may be on the charger side, and the second power transmission / reception device (213) may be on the mobility or chargeable device side.

[0168] Meanwhile, in FIG. 3, the first power transmission / reception device (113) and the first active bridge (111) are shown as being separated for convenience of explanation, but the first active bridge (111) may be included in the first power transmission / reception device (113).

[0169] The above first power transmission and reception device (113) includes a first inductor (L1), a first switching control capacitor (SCC1), a second switching control capacitor (SCC2), and a first control unit (114).

[0170] The first inductor (L1) is coupled with the second inductor (L2) of the second power transmission / reception device (213) for wireless power transmission / reception. For example, the first inductor (L1) and the second inductor (L2) may be positively coupled to have a mutual inductance value M.

[0171] The first switching control capacitor (SCC1) and the second switching control capacitor (SCC2) are each electrically connected to the first inductor (L1). The specific connection will be described in more detail with reference to FIG. 4, which illustrates the structure of block (112) of FIG. 3.

[0172] The first control unit (114) controls the first switching control capacitor (SCC1) and the second switching control capacitor (SCC2).

[0173] When the first power transmission and reception device (113) receives wireless power from the second power transmission and reception device (213), the first control unit (114) controls the first switching control capacitor (SCC1) and the second switching control capacitor (SCC2) to switch between a constant current (CC) mode and a constant voltage (CV) mode. The CC mode will be described in detail with reference to FIG. 10, and the CV mode will be described in detail with reference to FIG. 11.

[0174] Referring to FIGS. 3 and 4, the first power transmission and reception device (113) includes a first capacitor (C f1 ) and a third inductor (L in1 ) may be further included. The first terminal (T1) of Fig. 4 is connected to the A-node of Fig. 3, and the second terminal (T2) is connected to the B-node of Fig. 3.

[0175] The above first capacitor (C f1 ) may be placed between the first end of the first inductor (L1) and the first node (N1). The third inductor (L in1 ) can be placed between the first node (N1) and the first terminal (T1).

[0176] At this time, the first switching control capacitor (SCC1) may be placed between the second node (N2) between the other end of the first inductor (L1) and the second terminal (T2) and the second terminal (T2). In addition, the second switching control capacitor (SCC2) may be placed between the first node (N1) and the second node (N2).

[0177] As an example, in the CC mode, the first control unit (114) may control the switches of the first switching control capacitor (SCC1) and the second switching control capacitor (SCC) to be turned on, and in the CV mode, the first control unit (114) may control the switches of the first switching control capacitor (SCC1) and the second switching control capacitor (SCC2) to be turned off. Specific switching operations of the CC mode and CV mode will be described in more detail with reference to FIGS. 10 and 11, respectively.

[0178] As an example, when the first power transmission / reception device (113) transmits wireless power to the second power transmission / reception device (213), the first control unit (114) can control the switch of the first switching control capacitor (SCC1) to be turned on and the switch of the second switching control capacitor (SCC2) to be turned off. The specific switching operation will be described in more detail with reference to FIG. 9.

[0179] As described above, the first power transmission and reception device (113) may further include a first active bridge (111) electrically connected to the first terminal (T1) and the second terminal (T2).

[0180] In the first active bridge (111), when the G1 switch and the G4 switch are turned on and the G2 switch and the G3 switch are turned off, a high potential is applied to the A node and a low potential is applied to the B node. Conversely, when the G2 switch and the G3 switch are turned on and the G1 switch and the G4 switch are turned off, a high potential is applied to the B node and a low potential is applied to the A node. By repeating this switching operation, high and low potentials are alternately repeated at the A node and the B node, so that the direct current is converted into alternating current.

[0181] Referring again to FIG. 3, a second power transmission / reception device (213) according to an exemplary embodiment of the present invention wirelessly transmits power to a first power transmission / reception device (113) and receives power wirelessly from the first power transmission / reception device (113). For example, the second power transmission / reception device (213) may be a mobility or chargeable device side, and the first power transmission / reception device (113) may be a charger side.

[0182] Meanwhile, in FIG. 3, the second power transmission / reception device (213) and the second active bridge (211) are shown as being separated for convenience of explanation, but the second active bridge (211) may be included in the second power transmission / reception device (213).

[0183] The second power transmission / reception device (213) includes a second inductor (L2), a third switching control capacitor (SCC3), and a second control unit (214).

[0184] The second inductor (L2) is coupled with the first inductor (L1) of the first power transmission / reception device (113) for wireless power transmission / reception. For example, the second inductor (L2) and the first inductor (L1) may be positively coupled to have a mutual inductance value M.

[0185] The third switching control capacitor (SCC3) is electrically connected to the second inductor (L2). The specific connection will be described in more detail with reference to FIG. 5, which illustrates the structure of block (212) of FIG. 3.

[0186] The second control unit (214) controls the third switching control capacitor (SCC3).

[0187] When the second power transmission and reception device (213) transmits wireless power to the first power transmission and reception device (113), the second control unit (214) controls the third switching control capacitor (SCC3) to switch between a constant current (CC) mode and a constant voltage (CV) mode. The CC mode will be described in detail with reference to FIG. 10, and the CV mode will be described in detail with reference to FIG. 11.

[0188] Referring to FIGS. 3 and 5, this second power transmission and reception device (213) includes a second capacitor (C f2 ), the fourth inductor (L in2 ) and the third capacitor (C s) may be further included. The third terminal (T3) of Fig. 5 is connected to the a-node of Fig. 3, and the fourth terminal (T4) is connected to the b-node of Fig. 3.

[0189] The second capacitor (C) f2 ) can be placed between one end of the second inductor (L2) and the third node (N3). The fourth inductor (L in2 ) can be placed between the third node (N3) and the third terminal (T3). The third capacitor (C s ) can be placed between the fourth node (N4) between the fourth terminal (T4) and the other end of the second inductor (L2).

[0190] At this time, the third switching control capacitor (SCC3) is the second capacitor (C f2 ) can be connected in parallel.

[0191] As an example, in the CC mode, the second control unit (214) may control the switch of the third switching control capacitor (SCC3) to be in an off state, and in the CV mode, the second control unit (214) may control the switch of the third switching control capacitor (SCC3) to be in an on state. The specific switching operations of the CC mode and the CV mode will be described in more detail with reference to FIGS. 10 and 11, respectively.

[0192] As an example, when the first power transmission / reception device (113) transmits wireless power to the second power transmission / reception device (213), the second control unit (214) can control the switch of the third switching control capacitor (SCC3) to be turned on. The specific switching operation will be described in more detail with reference to FIG. 9.

[0193] As described above, the second power transmission and reception device (213) may further include a second active bridge (211) electrically connected to the third terminal (T3) and the fourth terminal (T4).

[0194] In the second active bridge (211), when a high potential is applied to node a and a low potential is applied to node b, the G5 and G8 switches are turned on, and the G6 and G7 switches are turned off, so that a high potential is applied to the upper electrode of the capacitor Co, and a low potential is applied to the lower electrode of the capacitor Co. Conversely, when a low potential is applied to node a and a high potential is applied to node b, the G5 and G8 switches are turned off, and the G6 and G7 switches are turned on, so that a high potential is applied to the upper electrode of the capacitor Co, and a low potential is applied to the lower electrode of the capacitor Co in the same manner as before. Through this operation, alternating current can be converted to direct current. The case of full-wave rectification has been described above, but in the case of half-wave rectification, when the potentials of nodes a and b are changed, half-wave rectification can also be implemented by turning off all switches.

[0195] Hereinafter, the detailed operation of a two-way wireless charging system according to an exemplary embodiment of the present invention having the connection structure described above will be described with reference to FIGS. 9 to 11. Before that, resonant networks applied thereto and explained therefor will be described in detail with reference to FIGS. 6 to 8.

[0196]

[0197] Fig. 6 is a circuit diagram showing a VC resonant network as a VC conversion.

[0198] Figure 6 is a VC resonant network, which has resonance conditions as in mathematical expression 1 below and output characteristics as in mathematical expression 2.

[0199]

[0200]

[0201]

[0202] Fig. 7 is a circuit diagram showing a CV resonant network as a CV converter.

[0203] Fig. 7 is a CV resonant network, which has resonance conditions as in Equation 3 below and output characteristics as in Equation 4.

[0204]

[0205]

[0206]

[0207] Fig. 8 is a circuit diagram showing a CC resonance network as a CC conversion.

[0208] Figure 8 is a CC resonance network, which has resonance conditions as in mathematical expression 5 below and output characteristics as in mathematical expression 6.

[0209]

[0210]

[0211]

[0212] Hereinafter, with reference to FIGS. 9 to 11, the detailed operation of a two-way wireless charging system according to an exemplary embodiment of the present invention will be described.

[0213]

[0214] Fig. 9 is an equivalent circuit diagram showing the operation of the first power transmission / reception device and the second power transmission / reception device illustrated in Fig. 3 in a constant current (CC) mode when the first power transmission / reception device wirelessly transmits power to the second power transmission / reception device. In Fig. 9, the circuit of the blocks of Figs. 4 and 5 is added to Fig. 3, and the inductive coupler of Fig. 3 is converted into a T-type equivalent circuit and displayed.

[0215] Referring to FIGS. 3 to 5 and 9, in a two-way wireless charging system according to an exemplary embodiment of the present disclosure, the first switching control capacitor (SCC1) is turned on, the second switching control capacitor (SCC2) is turned off, and the third switching control capacitor (SCC3) is turned on, so that a first power transmission / reception device can implement a constant current (CC) mode when transmitting wireless power to a second power transmission / reception device.

[0216] AC power source U of Fig. 9 AB In the supply side power circuit (11) of Fig. 3, it refers to power converted to AC by passing through the first active bridge (111). After being converted to AC in this way, by the operation of the first and second switching control capacitors (SCC1, SCC2) and the third switching control capacitor (SCC3), a VC resonant network, a first power factor improvement network (ZPA1), a CC resonant network, and a second power factor improvement network (ZPA2) are sequentially formed, and the network is operated in a constant current (CC) mode.

[0217] In more detail, the AC power (U) is converted to AC through the first active bridge (111). AB ) passes through the VC resonance network. At this time, the first switching control capacitor (SCC1) is turned on, and the second switching control capacitor (SCC2) is turned off. In this way, when the switch of the first switching control capacitor (SCC1) is turned on, and the switch of the second switching control capacitor (SCC2) is turned off, the impedance of the first switching control capacitor (SCC1) decreases compared to the impedance of the inductor (Lin1) and the impedance of the capacitance (Cp1), so that the first switching control capacitor (SCC1) can be ignored, and accordingly, the VC resonance network of FIG. 6 is formed to generate a constant current (CC, i p ) is formed.

[0218] After that, a constant current (ip ) improves the power factor by reducing the phase difference between power and current through the first power factor improvement network (ZPA1), and then passes through the CC resonant network shown in Fig. 8 to generate a new constant current (i ab ) is formed. At this time, the third switching control capacitor (SCC3) is also turned on, and the inductance (L) by the equivalent circuit of the T-type inductive coupler s,lk ) when the impedance of the third switching control capacitor (SCC3) becomes negligibly small compared to the impedance of the third switching control capacitor (SCC3), a CC resonant network as shown in Fig. 8 is formed.

[0219] At the rear end, a new constant current (i ab ) is supplied to electric vehicles by improving the power factor through the second power factor improvement network (ZPA2).

[0220]

[0221] Fig. 10 is an equivalent circuit diagram showing the operation of the first power transmission / reception device and the second power transmission / reception device illustrated in Fig. 3 in a constant current (CC) mode when the second power transmission / reception device wirelessly transmits power to the first power transmission / reception device. As in the previous drawings, in Fig. 10, the circuits of the blocks of Figs. 4 and 5 are added to Fig. 3, and the inductive coupler of Fig. 3 is converted into a T-type equivalent circuit and displayed.

[0222] AC power supply U of Fig. 10 ab In the EV side power circuit (21) of Fig. 3, it refers to power converted to AC by passing through the second active bridge (211). After being converted to AC in this way, by the operation of the first and second switching control capacitors (SCC1, SCC2) and the third switching control capacitor (SCC3), a VC resonant network, a first power factor improvement network (ZPA1), a CC resonant network, and a second power factor improvement network (ZPA2) are sequentially formed, and the network is operated in a constant current (CC) mode.

[0223] In more detail, the AC power (U) is converted to AC through the second active bridge (211). ab ) passes through the VC resonance network.

[0224] Afterwards, the power factor is improved by reducing the phase difference between power and current through the first power factor improvement network (ZPA1), and then the power is supplied to the grid by sequentially passing through the CC resonance network and the second power factor improvement network shown in Fig. 8.

[0225] At this time, the second switching control capacitor (SCC2) is turned off, and the switch of the first switching control capacitor (SCC1) is controlled to improve the power factor.

[0226] Meanwhile, the constant current iAB generated through this process can be expressed as in mathematical equation 7 below.

[0227]

[0228]

[0229] Fig. 11 is an equivalent circuit diagram showing the operation of the first power transmission / reception device and the second power transmission / reception device illustrated in Fig. 3 in a constant voltage (CV) mode when the second power transmission / reception device wirelessly transmits power to the first power transmission / reception device. As in the previous drawings, in Fig. 11, the circuits of the blocks of Figs. 4 and 5 are added to Fig. 3, and the inductive coupler of Fig. 3 is converted into a T-type equivalent circuit and displayed.

[0230] AC power source U of Fig. 11 abIn the EV side power circuit (21) of Fig. 3, it refers to power that has been converted to AC by passing through the second active bridge (211). After being converted to AC in this way, by the operation of the first and second switching control capacitors (SCC1, SCC2) and the third switching control capacitor (SCC3), a VC resonant network, a first power factor improvement network (ZPA1), a CC resonant network, and a CV resonant network are sequentially configured, and the circuit is operated in a constant voltage (CV) mode.

[0231] In more detail, the AC power (U) is converted to AC through the second active bridge (211). ab ) passes through the VC resonance network.

[0232] Afterwards, the power factor is improved by reducing the phase difference between power and current through the first power factor improvement network (ZPA1), and then the power is supplied to the grid by sequentially passing through the CC resonance network illustrated in FIG. 8 and the CV resonance network illustrated in FIG. 7.

[0233] At this time, the switches of the second switching control capacitor (SCC2) and the first switching control capacitor (SCC1) are turned on.

[0234] That is, the turned-on second switching control capacitor (SCC2) forms a CV resonance network at the rear end, and the switch of the first switching control capacitor (SCC1) at this time is turned on, thereby reducing the impedance as described above.

[0235] Meanwhile, the constant voltage UAB generated through this process can be expressed as in mathematical equation 8 below.

[0236]

[0237]

[0238] Meanwhile, when the second power transmitting and receiving device wirelessly transmits power to the first power transmitting and receiving device, comparing FIG. 10 and FIG. 11, which illustrate the constant current (CC) mode and the constant voltage (CV) mode, respectively, switching from the constant current (CC) mode to the constant voltage (CV) mode can be implemented by turning on the switches of the first and second switching control capacitors (SCC1, SCC2).

[0239] That is, the two-way wireless charging system according to an exemplary embodiment of the present disclosure can switch the second power factor improvement network (ZPA2) and the CV resonant network by turning on / off the first and second switching control capacitors (SCC1, SCC2).

[0240]

[0241] FIG. 12 is a flowchart illustrating a bidirectional power transmission control method according to an exemplary embodiment of the present disclosure.

[0242] Referring to FIG. 12, a bidirectional power transmission control method between a first power transmission / reception device including first and second switching control capacitors (SCC1, SCC2) and a second power transmission / reception device including a third switching control capacitor (SCC3) comprises a step (S110) of sensing a state of charge (SoC) of a battery, a step (S120) of determining a constant current (CC) mode and a constant voltage (CV) mode according to the sensed state of charge of the battery, and a step (S130) of controlling switches of SCC1, SCC2, and SCC3 according to the determined mode.

[0243] As described above, the first power transmission / reception device may be on the charger side, and the second power transmission / reception device may be on the mobility or chargeable device side.

[0244] As a result of sensing the state of charge (SoC) of the battery (S110), if the SoC of the battery is below a set value, it can be determined as CV mode, and if the SoC of the battery exceeds the set value, it can be determined as CC mode (S120).

[0245] Meanwhile, when the second power transmission / reception device transmits wireless power to the first power transmission / reception device, in the CC mode, as described in FIG. 10, the second power transmission / reception device and the first power transmission / reception device may configure a VC resonant network, a first power factor improvement network (ZPA1), a CC resonant network, and a second power factor improvement network (ZPA2), and in the CV mode, as described in FIG. 11, the second power transmission / reception device and the first power transmission / reception device may configure a VC resonant network, a first power factor improvement network (ZPA1), a CC resonant network, and a CV resonant network.

[0246] As an example, when the first power transmission / reception device transmits wireless power to the second power transmission / reception device, as described in FIG. 9, the first power transmission / reception device and the second power transmission / reception device may configure a VC resonant network, a first power factor improvement network (ZPA1), a CC resonant network, and a second power factor improvement network (ZPA2). Since this process has been described above, a redundant description will be omitted.

[0247] In the embodiments of FIGS. 1 to 12, although omitted in the drawings, a processor and a memory are electronically connected to each component to perform at least a part of the process of controlling various parameters for performing communication, data collection / acquisition, operation conditions determination, calculation, decision process, and / or wireless power transmission for obtaining effective impedance characteristics, and / or wireless power transmission. The processor and memory may be controlled or managed by the processor.

[0248] At least a portion of the above communication, data collection / acquisition, computation, calculation, decision, and / or control processes may be executed by the computing system (3000) of FIG. 13.

[0249]

[0250] FIG. 13 is a block diagram illustrating a generalized configuration of a generalized wireless power transmitting pad device, a wireless power receiving pad device, a wireless power transfer (WPT) system, or a computing system controlling them according to one embodiment of the present invention.

[0251] Referring to FIG. 13, a computing system (3000) according to one embodiment of the present invention may include at least one processor (3100) and a memory (3200) that stores instructions that instruct the at least one processor (3100) 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 (3100) loading and executing instructions from the memory (3200).

[0252] The processor (3100) 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.

[0253] Each of the memory (3200) and the storage device (3400) may be configured with at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory (3200) may be configured with at least one of a read-only memory (ROM) and a random access memory (RAM).

[0254] Additionally, the computing system (3000) may include a communication interface (3300) that performs communication via a wired / wireless network.

[0255] Additionally, the computing system (3000) may further include a storage device (3400), an input interface (3500), an output interface (3600), etc.

[0256] Additionally, each component included in the computing system (3000) can communicate with each other by being connected by a bus (3700).

[0257] A device including a processor (3100) according to one embodiment of the present invention may be, for example, a communicable desktop computer, a laptop computer, a notebook, a smart phone, a tablet PC, a mobile phone, a smart watch, smart glasses, 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.

[0258] A device for controlling power transmission or determining operating conditions according to one embodiment of the present invention may be installed on the electric vehicle and / or charging station side in relation to an electric vehicle charging system, an electric vehicle power supply equipment (EVSE), and / or a charging manipulator, and may include a processor (3100) that receives and executes at least one command from a memory (3200).

[0259] A processor (3100) of a device for charging an electric vehicle according to one embodiment of the present invention can perform a method executed by a computing system or controller on the charging station side that is linked to an electric vehicle power supply unit (EVSE) including a charging manipulator.

[0260] The processor (3100) of the device for charging an electric vehicle according to one embodiment of the present invention can perform a method executed by a computing system or controller on the electric vehicle side.

[0261] The operations 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. A computer-readable recording medium includes any type of recording device that stores information readable by a computer system. Furthermore, a computer-readable recording medium can be distributed across network-connected computer systems, allowing the computer-readable program or code to be stored and executed in a distributed manner.

[0262] 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.

[0263] 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.

[0264] 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.

[0265] 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 first power transmitting / receiving device for wirelessly transmitting power to a second power transmitting / receiving device and receiving power wirelessly from the second power transmitting / receiving device, A first inductor coupled with a second inductor of the second power transmitting and receiving device for wireless power transmission and reception; A first switching control capacitor (SCC) electrically connected to the first inductor; a second switching control capacitor (SCC) electrically connected to the first inductor; and A first control unit for controlling the first SCC and the second SCC is included, When the first power transmitting and receiving device receives wireless power from the second power transmitting and receiving device, the first control unit controls the first SCC and the second SCC to switch between a constant current (CC) mode and a constant voltage (CV) mode. First power transmitter and receiver device.

2. In claim 1, The above first power transmission and reception device is on the charger side, The second power transmission and reception device is on the mobility or chargeable device side, First power transmitter and receiver device.

3. In claim 1, A first capacitor placed between one end of the first inductor and the first node; and A third inductor disposed between the first node and the first terminal; Including more, The first SCC is arranged between the second node between the other terminal and the second terminal of the first inductor and the second terminal, The second SCC is disposed between the first node and the second node, First power transmitter and receiver device.

4. In claim 3, In the above CC mode, the first control unit controls the switches of the first SCC and the second SCC to be turned on, In the case of the above CV mode, the first control unit controls the switches of the first SCC and the second SCC to be in the off state. First power transmitter and receiver device.

5. In claim 4, When the first power transmitting and receiving device transmits wireless power to the second power transmitting and receiving device, The first control unit controls the switch of the first SSC to be turned on, and controls the switch of the second SCC to be turned off. First power transmitter and receiver device.

6. In claim 3, Further comprising a first active bridge electrically connected to the first terminal and the second terminal, First power transmitter and receiver device.

7. A second power transmitting and receiving device for wirelessly transmitting power to a first power transmitting and receiving device and receiving power wirelessly from the first power transmitting and receiving device, A second inductor coupled to the first inductor of the first power transmitter / receiver for wireless power transmission / reception; a third switching control capacitor (SCC) electrically connected to the second inductor; and Including a second control unit that controls the third SCC, When the second power transmission / reception device transmits wireless power to the first power transmission / reception device, the second control unit controls the third SCC to switch between a constant current (CC) mode and a constant voltage (CV) mode. Second power transmitter and receiver device.

8. In claim 7, The above first power transmission and reception device is on the charger side, The second power transmission and reception device is on the mobility or chargeable device side, Second power transmitter and receiver device.

9. In claim 7, A second capacitor placed between one end of the second inductor and the third node; a fourth inductor disposed between the third node and the third terminal; and A third capacitor disposed between the fourth terminal and the fourth node between the other terminal of the second inductor; Including more, The above third SCC is connected in parallel with the second capacitor, Second power transmitter and receiver device.

10. In claim 9, In the above CC mode, the second control unit controls the switch of the third SCC to be turned off, In the case of the above CV mode, the second control unit controls the switch of the third SCC to be turned on. Second power transmitter and receiver device.

11. In claim 10, When the first power transmitting and receiving device transmits wireless power to the second power transmitting and receiving device, The second control unit controls the switch of the third SSC to be turned on. Second power transmitter and receiver device.

12. In claim 9, Further comprising a second active bridge electrically connected to the third terminal and the fourth terminal, Second power transmitter and receiver device.

13. A bidirectional power transmission control method between a first power transmission / reception device including first and second switching control capacitors (SCC1, SCC2) and a second power transmission / reception device including a third switching control capacitor (SCC3), Step of sensing the state of charge (SoC) of the battery; A step of determining a constant current (CC) mode and a constant voltage (CV) mode according to the sensed state of charge of the battery; and According to the determined mode, a step of controlling the switches of SCC1, SCC2 and SCC3 is included. Bidirectional power transmission control method.

14. In claim 13, The above first power transmission and reception device is on the charger side, The second power transmission and reception device is on the mobility or chargeable device side, Bidirectional power transmission control method.

15. In claim 14, As a result of sensing the battery's state of charge (SoC), If the SoC of the above battery is below the set value, it is determined as CV mode, Characterized in that, if the SoC of the above battery exceeds the set value, it is determined to be in CC mode. Bidirectional power transmission control method.

16. In claim 14, When the second power transmission / reception device transmits wireless power to the first power transmission / reception device, In the CC mode, the second power transmission and reception device and the first power transmission and reception device form a VC resonant network, a first power factor improvement network, a CC resonant network, and a second power factor improvement network, In the CV mode, the second power transmission and reception device and the first power transmission and reception device constitute a VC resonant network, a first power factor improvement network, a CC resonant network, and a CV resonant network. Bidirectional power transmission control method.

17. In claim 14, When the first power transmission / reception device transmits wireless power to the second power transmission / reception device, The first power transmission and reception device and the second power transmission and reception device constitute a VC resonant network, a first power factor improvement network, a CC resonant network, and a second power factor improvement network. Bidirectional power transmission control method.

Images