Split-phase magnetic couplers for integration of onboard chargers into wireless charging systems

Abstract

A system and method for integrated charging of an electric vehicle, the system and method being capable of transferring power wirelessly and through direct charging is proposed. The system contains a wireless transmitter containing a coil for producing a magnetic field when coupled to a first power source, and a transformer electrically coupled to a second power source. The wireless transmitter is capable of inducing a current in a shared receiver, the shared receiver having a split-phase coil containing a first node for receiving current form the transformer, and at least two output nodes. The two output nodes are electrically coupled to a shared resonant network, a shared rectifier and an energy storage device in series.

Description

SPLIT-PHASE MAGNETIC COUPLERS FOR INTEGRATION OF ONBOARD CHARGERS INTO WIRELESS CHARGING SYSTEMSCROSS REFERENCE

[0001] This application is a non-provisional of, and claims all benefit including priority to, US Application No. 63 / 652,112, entitled “SPLIT-PHASE MAGNETIC COUPLERS FOR INTEGRATION OF ONBOARD CHARGERS INTO WIRELESS CHARGING SYSTEMS”, filed May 27, 2024, incorporated herein by reference in its entirety.FIELD

[0002] Embodiments of the present disclosure relate to electrical systems, circuits and devices, and more specifically, embodiments relate to devices, systems and methods for improved integration of wireless and onboard charging systems, namely split-phase magnetic couplers for integration of onboard chargers into wireless charging systems, for example, for practical use with electric vehicles.INTRODUCTION

[0003] Wireless power transfer (WPT), DC charging, and an onboard charger (OBC) are the primary methods for charging electric vehicles (EVs) at different power levels. Wired charging involves physically connecting the OBC of a vehicle to a charging station using a cable. In contrast, wireless charging uses electromagnetic induction to transfer energy from a charging pad on the ground assembly (GA) to a receiver on the vehicle. Therefore, wireless charging may offer a safer, more convenient, reliable, and automated charging process compared to conventional conductive (wired) charging. An onboard charger (OBC) for EVs includes a power factor correction (PFC) circuit, a high-frequency inverter, an isolating transformer, and a rectifier stage. Resonant compensations can also be used in an OBC to improve efficiency. Similarly, a wireless charger (WC) consists of two parts: transmitter and receiver. On the transmitter side, a PFC is used to connect the converter to the grid; there is an inverter to generate a frequency source, resonant networks, and a transmitter coil, which is magnetically coupled with the receiver coil with a mutual inductance of M.

[0004] Different magnetic coupler layouts are used in wireless power transfer (WPT) systems, but circular, rectangular, and Double-D (DD) layouts are the most common. Previousapproaches to improving power transfer have utilized multi-phase magnetic couplers on both the transmitter and receiver side. However, a technical drawback of this approach is that it is prone to reduced efficiency and output power due to misalignment of the coils, which is an issue which may arise when a user must “park” a vehicle on-top of the transmitter coils. Other approaches have implemented multi-polar magnetic couplers, for example, to overcome the limitations of multi-phase systems. For example, a rectangular magnetic coupler may be a unipolar type, while a DD structure may be a bipolar type.

[0005] However, as the number of magnetic poles increases, the design of the magnetic coupler may become more complex, resulting in higher costs, structural circuitry and weight for the overall structure. Due to the complexity of the WC system, it may be difficult from a cost, safety and structural perspective to implement both an OBC and WC system within a single vehicle assembly. Therefore, improved systems and methods for OBC and WC systems are desired.SUMMARY

[0006] The present disclosure provides a novel method and system for integrating the OBC and WC modes in an integrated (e.g. single) EV charging system. In the proposed system and method, some of the components, such as resonant inductors, resonant capacitors, and rectifiers, are shared between the OBC and WC systems. Therefore, the proposed embodiments help to reduce the overall cost, structural complexity and safety of vehicle assembly (VA) when both wired and wireless charging methods are desired. The principles of operation of this integration method, different topologies, and simulation results are presented in the following sections, corresponding circuits, systems and devices are also proposed. These features can be practically incorporated in an improved electric vehicle / electric vehicle charging system.

[0007] An integrated charging system is proposed for an electric vehicle capable of transferring power wirelessly and through onboard charging. The integrated charging system has a shared coil structure, at least two power sources, a first power source within a wireless ground assembly, a second power source electrically coupled to a transformer, a sharedreceiver, a shared resonant network and a shared rectifier. A number of variants are proposed having different topologies with different combinations of benefits and drawbacks.

[0008] The first power source may be electrically coupled to a wireless transmitter and the wireless transmitter contains at least one coil for producing a magnetic field. The shared receiver is electrically coupled to the transformer and inductively coupled to the wireless transmitter, the shared receiver contains at least one split-phase coil to receive an induced current from the wireless transmitter. The shared receiver further contains a first node for receiving current from the transformer, and at least two output nodes. The shared resonant network is electrically coupled to the two output nodes. The shared rectifier is electrically coupled between the shared resonant network and an energy storage device, the energy storage device is configured to store power received from at least one of the wireless transmitter and transformer.

[0009] In some embodiments, the at least one split-phase coil is a three-phase magnetic coupler, and upon the three-phase magnetic coupler aligning with the magnetic field, the induced current has a phase shift of 120°. Further, upon the three-phase magnetic coupler receiving current from the transformer, the current in the split-phase coil has a 0° phase shift.

[0010] In some embodiments, the at least one split-phase coil is formed from a pair of parallel wire paths comprising at least two wires beginning at the at least two output nodes and merging at the first node.

[0011] In a further embodiment, upon the split-phase coil being aligned with the magnetic field, the induced current within the two wires of the parallel wire path flow in the same direction, and upon the split-phase coil receiving current from the transformer, the current within the two wires of the two parallel wire paths flow in opposite directions.

[0012] In a further embodiment, the split-phase magnetic coupler is one of a uni-polar and multi-polar structure, and / or is one of a circular, rectangular and double-D coil structure.

[0013] In a further embodiment, the shared resonant network comprises at least one of a resonant inductor and resonant capacitor.

[0014] In a further embodiment, the shared receiver, shared resonant network and shared rectifier form a shared charging assembly for both wireless and onboard charging.

[0015] In a further embodiment, the shared charging assembly contains shared mechanical components comprising at least one of an enclosure, printed circuit boards, connectors, contactors, heatsinks, thermal pads, cold plate, and cables.

[0016] In a further embodiment, the two wires of the parallel wire path are twisted to form a helical shape.

[0017] In a further embodiment, the energy storage device is a battery, and the battery, shared receiver, shared resonant network, shared rectifier and transformer are housed within an electric vehicle assembly.

[0018] In some embodiments, a method is proposed for integrated charging of an energy storage device, the energy storage device being charged by current provided from at least two power sources. The proposed method further comprising electrically coupling a wireless transmitter to a first power source within a wireless group assembly and the wireless transmitter generating a magnetic field through a coil, electrically coupling a transformer to a second power source, aligning at least one split-phase coil of the shared receiver with the magnetic field of the wireless transmitter, and / or transferring, through the transformer, current to the at least one split-phase coil, wherein the wireless transmitter generates an induced current in the split-phase coil, and the transformer is electrically coupled to a first node of the split phase coil, providing a shared resonant network and shared rectifier coupled to the shared receiver in series, the shared resonant network electrically coupled to two output nodes on the shared receiver, and transferring at least one of the induced current and the current from the shared rectifier to the energy storage device.

[0019] In some embodiments, the at least one split-phase coil is a three-phase magnetic coupler. In a further embodiment, upon the three-phase magnetic coupler being aligned with the magnetic field, the induced current has a phase shift of 120°; and upon the three-phase magnetic coupler receiving current from the transformer, the current in the split-phase coil has a 0° phase shift.

[0020] In some embodiments, the proposed method comprises forming the at least one split-phase coil from a pair of parallel wire paths forming at least two wires beginning at the at least two output nodes and merging at the first node.

[0021] In some embodiments, upon the split-phase coil being aligned with the magnetic field, the induced current within the two wires of the parallel wire path flow in the same direction, and upon the split-phase coil receiving current from the transformer, the current within the two wires of the two parallel wire path flow in opposite directions.

[0022] In a further embodiment, the split-phase magnetic coupler is one of a uni-polar and multi-polar structure, and / or is one of a circular, rectangular and double-D coil structure.

[0023] In a further embodiment, the shared resonant network comprises at least one of a resonant inductor and resonant capacitor.

[0024] In a further embodiment, the proposed method comprises assembling the shared receiver, shared resonant network and shared rectifier in shared charging assembly for both wireless and onboard charging.

[0025] In some embodiments, the shared charging assembly contains shared mechanical components comprising at least one of an enclosure, printed circuit boards, connectors, contactors, heatsinks, thermal pads, cold plate, and cables.

[0026] In a further embodiment, the method comprises twisting the two wires of the parallel wire path to form a helical shape.

[0027] In some embodiments, a current balancing circuit is electrically coupled to the at least one split-phase magnetic coupler

[0028] In a further embodiment, the energy storage device is a battery, and further comprising housing the battery, shared receiver, shared resonant network, shared rectifier and transformer within an electric vehicle assembly.

[0029] In some embodiments, the system and method may further integrate a current balancing network, active switching components, and a control software which may be controlled by a processor configured to implement computer interpretable instruction sets.

[0030] Embodiments described herein introduce a wireless charging system comprising an onboard charger and a wireless charging system. The wireless charging system contains a wireless charger receiver which has one or more coils for receiving power through a magnetic field coupled to a wireless charger transmitter. The onboard charger is connected to the wireless charger system through a connection point on the primary wireless charging circuit. The onboard charger and wireless charging system share some common components comprising a shared resonant network and a shared rectifier.

[0031] Structural components include, but are not limited to, an onboard charging network comprising a power factor correction circuit, an inverter and a transformer for transferring power to the integrated system. A wireless charging network comprising a power factor correction circuit, an inverter and a wireless charger transmitter. An integrated charging component comprising a wireless charger receiver such as a split-phase magnetic coupler, a resonant network and a rectifier. The integrated charging component providing as an output a flow of power to a battery.

[0032] In use, the integrated charging network interoperates with the onboard charging network and the wireless charging network to perform steps of a method including, but not limited to, receiving power from either the onboard charging network or wireless charging network, the integrated charging component using the wireless charger receiver to receive the power at a split phase magnetic coupler, converting the power to a desired resonant frequency and then converting the power to a lower voltage which is then provided to the energy storage device for charging.

[0033] The improvements proposed herein can help improve the adoption of certain technologies such as, but not limited to, electric and hybrid vehicles, and adoption of these green technologies can help mitigate environmental impacts and conserve the natural environment and natural resources.

[0034] The system may be used for high voltage vehicles such as buses, trucks, industrial equipment (i.e. cranes, forklifts, etc.), taxis, consumer vehicles, drones and the like. As wireless charging may be preferred when charging at a high voltage, the proposed system and method may be configured to have the WC as the default charging mode, and the OBC may be a back-up option available to the user when needed.

[0035] The system is configured to interoperate with standard ground charging systems for wireless charging. The system may be implemented as a retrofit within an existing vehicle assembly, or may be sold as a stand-along circuitry structure which can be implemented within a new build vehicle. For example, the proposed system may be used for wireless charging of vehicles which have a wireless receiver pad positioned preferably on the exterior of the bottom / floor of the vehicle structure. The receiver pad may be aligned with a transmitter pad (i.e., through manoeuvring and parking the vehicle over the pad) which may permit the receiver pad to receive an induced current from the magnetic field generated by the transmitter pad. Further, the proposed system may be used for on-board charging which may comprise direct electrical coupling between a charging station and an input terminal on the vehicle. The charging station may transfer current to the input terminal which is electrically coupled to a transformer within the vehicle assembly. The transformer may step down or step up the voltage received from the charging station to a voltage level suitable for the electric vehicle energy storage device within the vehicle assembly.

[0036] In some embodiments, the proposed system may be suitable for autonomous vehicles and electric vehicles with high power ratings. When used for an autonomous vehicle, such as a taxi, passenger vehicles, vacuum cleaner, arial drone, etc., the wireless charging mode may be the preferred charging approach, allowing the autonomous vehicle to return without user intervention to a charging station after the battery has been depleted below a predetermined threshold. However, due to the integration of the OBC within the system, an autonomous vehicle would have the ability to receive a charge from a mechanically connected charging source (i.e. through a terminal) if it was incapable of returning to the charging station.

[0037] When used for an electric vehicle with a higher power rating then most consumer vehicles, such as a bus, transport vehicles, cranes, forklifts, or other vehicles used in shipping and warehouse operations, the proposed system and method may permit the transfer of ahigh voltage source in WC mode which thereby reduces downtime and allows the vehicles to return to operation with a full charge in a relatively short amount of time.

[0038] In some circumstances, OBC mode may be preferred for charging, even if it would be possible to return to a charging station. For example, when the vehicle battery has reached below a minimum threshold, such as 30% charge, it may be preferable to use the OBC mode in order to preserve battery health due to the potential damage which can be caused by exposing the depleted battery to the higher power provided in WC mode.

[0039] Further, if an electric vehicle is unable to return to a ground charging station prior to the battery being completely or substantially depleted, the electric vehicle may be able to have a power source brought to its location (such as a portable generator) which can charge the electric vehicle in OBC mode such that the battery is returned to a power level sufficient to arrive at a ground charging station to receive the remaining charge through a WC.

[0040] The proposed system may be designed for the WC mode to be the primary charging method. The high voltage which is capable of being provided by the proposed system in WC mode allows for more efficient and timely charging without the need to have a person present at the time of charging to connect physical terminals. However, the integrated circuit provides the possibility of OBC mode at a reduced cost and complexity, due to the shared components, which can be used as a fail safe if an electric vehicle would prefer OBC mode or otherwise be unable to reach a ground charging station. Further, implementing the split-phase magnetic coupler in an integrated charging system may reduce or eliminate the magnetic field leakage generated by the wireless charger receiver during OBC mode by configuring the coil branches to form parallel and opposite current pathways for the current in OBC mode that cancel out any magnetic field generated by the individual coil branches.DESCRIPTION OF THE FIGURES

[0041] In the figures, embodiments are illustrated by way of example. It is to be expressly understood that the description and figures are only for the purpose of illustration and as an aid to understanding.

[0042] Embodiments will now be described, by way of example only, with reference to the attached figures, wherein in the figures:

[0043] FIG. 1A is a diagram of a conventional circular magnetic coupler for wireless charging, according to the prior art.

[0044] FIG. 1B is a diagram of a conventional rectangular magnetic coupler for wireless charging, according to the prior art.

[0045] FIG. 1C is a diagram of a conventional double-D magnetic coupler for wireless charging, according to the prior art.

[0046] FIG. 1D is a diagram of a conventional tripolar magnetic coupler for wireless charging, according to the prior art.

[0047] FIG. 1E is a diagram of a conventional unipolar three-phase magnetic coupler for wireless charging, according to the prior art.

[0048] FIG. 1F is a diagram of a conventional bi-polar three phase magnetic coupler for wireless charging, according to the prior art.

[0049] FIG. 2A is a configuration diagram of an electric vehicle assembly with seperate onboard charging and wireless charging.

[0050] FIG. 2B is a configuration diagram of an electric vehicle assembly with integrated wired and wireless charging, according to some embodiments.

[0051] FIG. 3A is a circuit diagram of a proposed split-phase rectangular (circular) coil layout for integration of an onboard charger into a wireless charger, according to some embodiments.

[0052] FIG. 3B is a circuit diagram of a proposed split-phase rectangular (circular) coil layout for integration of an onboard charger into a wireless charger during wireless charging mode, according to some embodiments.

[0053] FIG. 3C is a circuit diagram of a proposed split-phase rectangular (circular) coil layout for integration of an onboard charger into a wireless charger during onboard charging mode, according to some embodiments.

[0054] FIG. 3D is a circuit diagram of a topology of a proposed split-phase rectangular (circular) coil layout for integration of an onboard charger into a wireless charger, according to some embodiments.

[0055] FIG. 4A is a circuit diagram of a proposed split-phase double-D coil layout for integration of an onboard charger into a wireless charger, according to some embodiments.

[0056] FIG. 4B is a circuit diagram of a proposed split-phase double-D coil layout for integration of an onboard charger into a wireless charger during wireless charging mode, according to some embodiments.

[0057] FIG. 4C is a circuit diagram of a proposed split-phase double-D coil layout for integration of an onboard charger into a wireless charger during onboard charging mode, according to some embodiments.

[0058] FIG. 5A is a layout diagram of a proposed split-phase bipolar three-phase magnetic coupler for integration of an onboard charger into a wireless charger, according to some embodiments.

[0059] FIG. 5B is a layout diagram of a proposed split-phase bipolar three-phase magnetic coupler for integration of an onboard charger into a wireless charger during wireless charging mode, according to some embodiments.

[0060] FIG. 5C is a layout diagram of a proposed split-phase bipolar three-phase magnetic coupler for integration of an onboard charger into a wireless charger during onboard charging mode, according to some embodiments.

[0061] FIG. 6A is a simulated model of a magnetic field density and vector on YZ-plane of the proposed single-phase rectangular magnetic coupler in wireless charging mode using a finite element method analysis, according to some embodiments.

[0062] FIG. 6B is a simulated model of a magnetic field density at 2 cm from the surface in XY-plane of the proposed single-phase rectangular magnetic coupler in wireless charging mode using a finite element method analysis, according to some embodiments.

[0063] FIG. 6C is a simulated model of a magnetic field density and vector on YZ-plane of the proposed single-phase rectangular magnetic coupler in onboard charging mode using a finite element method analysis, according to some embodiments.

[0064] FIG. 6D is a simulated model of a magnetic field density at 2 cm from the surface in XY-plane of the proposed single-phase rectangular magnetic coupler in onboard charging mode using a finite element method analysis, according to some embodiments.

[0065] FIG. 7A is a simulated model of a magnetic field density and vector on XZ-plane of the proposed single-phase double-D magnetic coupler in wireless charging mode using a finite element method analysis, according to some embodiments.

[0066] FIG. 7B is a simulated model of a magnetic field density at 2 cm from the surface in XY-plane of the proposed single-phase double-D magnetic coupler in wireless charging mode using a finite element method analysis, according to some embodiments.

[0067] FIG. 7C is a simulated model of a magnetic field density and vector on XZ-plane of the proposed single-phase double-D magnetic coupler in onboard charging mode using a finite element method analysis, according to some embodiments.

[0068] FIG. 7D is a simulated model of a magnetic field density at 2 cm from the surface in XY-plane of the proposed single-phase double-D magnetic coupler in onboard charging mode using a finite element method analysis, according to some embodiments.

[0069] FIG. 8A is a simulated model of a magnetic field density and vector on YZ-plane of the proposed three-phase bipolar magnetic coupler in wireless charging mode using a finite element method analysis, according to some embodiments.

[0070] FIG. 8B is a simulated model of a magnetic field density at 2 cm from the surface in XY-plane of the proposed three-phase bipolar magnetic coupler in wireless charging mode using a finite element method analysis, according to some embodiments.

[0071] FIG. 8C is a simulated model of a magnetic field density and vector on YZ-plane of the proposed three-phase bipolar magnetic coupler in onboard charging mode using a finite element method analysis, according to some embodiments.

[0072] FIG. 8D is a simulated model of a magnetic field density at 2 cm from the surface in XY-plane of the proposed three-phase bipolar magnetic coupler in onboard charging mode using a finite element method analysis, according to some embodiments.DETAILED DESCRIPTION

[0073] Different magnetic coupler layouts are used in wireless power transfer (WPT) systems, but circular, rectangular, and Double-D (DD) layouts are the most common. FIGs. 1A, 1B, 1C, 1 D, 1E, 1F shows the layout of different well-known magnetic couplers used for high-power applications. The coil layout is flat, and the ferrite plate 102 is placed underneath the coil. This may assist in the flow of flux being primarily between the transmitter 104 and receiver coils 106 and returning to the ferrite plate 102. As a result, the ferrite plate 102 acts as a low reluctance path, and the magnetic flux may not leak into the vehicle's chassis.

[0074] One of the magnetic layouts is the circular magnetic coupler. The layout of this structure and its magnetic flux path is illustrated in FIG. 1A. The coils in this design are placed on top of ferrite plates 102 arranged in a radial pattern. When the coil generates magnetic flux, it flows outward from the magnetic plane and returns from the outer side of the magnetic coupler.

[0075] A rectangular magnetic coupler resembles the circular magnetic coupler shown in FIG. 1A, but with a squared layout formed by a process known as Quadrature (Q). The layout of the rectangular magnetic coupler is shown in FIG. 1 B. The ferrite plates 102 in this layout are arranged in a parallel manner. The flux path follows a similar pattern to that of a circular magnetic coupler, moving outward in the transmitter plane and then returning from the magnetic coupler's sides.

[0076] A DD magnetic coupler is shown in FIG. 1C. In this magnetic coupler layout, the flux has two opposite directions at the magnetic coupler plane. In the DD layout, the flux path is approximately equal to half of the magnetic coupler’s length. However, a circular layout seenin FIG. 1A may have a better coupling coefficient in comparison to DD magnetic couplers with the same occupied area. When the coils of a DD layout overlap, a bipolar magnetic coupler is formed, which may offer some advantages. For example, the bipolar magnetic coupler may have greater interoperability with other types of magnetic couplers and a greater tolerance for misalignment.

[0077] Magnetic couplers usually come in different configurations, such as unipolar (one magnetic pole), bipolar (two magnetic poles), and tripolar. For example, a rectangular magnetic coupler may be a unipolar type, while a DD structure may be a bipolar type.

[0078] Tripolar magnetic couplers consist of three receiver coils 106 that may be magnetically decoupled from each other and only coupled with their corresponding receiver coils 104, as shown in FIG. 1 D. It is important to note that the arrangement in FIG. 1D differs from a three-phase system, for example, as the coils of the tripolar wireless charging system of FIG. 1D may operate in sync or independently from one another because of the process of decoupling.

[0079] Previously, wireless power transmission techniques have been proposed, which use a three-phase magnetic coupler on both the transmitter 104 and receiver 106 side, as shown in FIG. 1 E. However, this approach is prone to reduced efficiency and output power due to misalignment of the coils. To overcome this limitation and improve the performance of three- phase wireless chargers, a bipolar three-phase magnetic coupler has been suggested, as shown in FIG. 1F. This modification aims to enhance both power density and efficiency.

[0080] However, as the number of magnetic poles increases, the design of the magnetic coupler may become more complex, resulting in higher costs, structural circuitry and weight for the overall structure. The increased weight, complexity and circuity required for certain magnetic couplers of a wireless charging system may be especially concerning as vehicle assemblies look to integrate both wireless and onboard charging functionalities into a single vehicle assembly.

[0081] Given that current solutions for WC systems in electric vehicles do not share components with the OBC systems, the WC and OBC circuits do not form an integratedsystem. The lack of integration requires separate, but overlapping, charging components for both WC and OBC functionality that results in a less compact and cost-effective topology. The benefit of reducing the complexity and structural components of a proposed charging system may be even more desirable in light of the use of multi-polar magnetic couplers which may further increase the weight, cost and complexity to the charging system. However, integration of the WC system and OBC system may lead to potential magnetic field leakage issues due to current flowing through the wireless receiver coils during OBC mode.

[0082] As will be discussed below, a series of charging structures are proposed which may reduce cost and complexity of the system, and improve the misalignment tolerance, increase the power level, and supply multiple loads at the same time.

[0083] The present disclosure provides a novel method and system for integrating OBC and WC systems in EVs. In the proposed system and method, some of the components, such as resonant inductors, resonant capacitors, and rectifiers, are shared between the OBC and WC systems. Therefore, the proposed embodiments may help to reduce the overall cost of vehicle assembly (VA) when both wired and wireless charging methods are desired. The principles of this integration method, different topologies, and simulation results are presented below.

[0084] Electric vehicles may include various types of commercially available assemblies, such as hybrid and fully electric vehicles. The term also encompasses consumer vehicles, transportation vehicles, autonomous vehicles, and drones, all of which can benefit from wireless charging (WC) technology.

[0085] The proposed integrated system may be used for wireless charging of vehicles which have a wireless receiver pad positioned preferably on the exterior of the bottom / floor of the vehicle structure. The receiver pad may be aligned with a transmitter pad (i.e., through manoeuvring and parking the vehicle over the pad) which may permit the receiver pad to receive an induced current from the magnetic field generated by the transmitter pad. Further, the proposed integrated system may be used for on-board charging which may comprise direct electrical coupling between a charging station and an input terminal on the vehicle. The charging station may transfer current to the input terminal which is electrically coupled to a transformer within the vehicle assembly. The transformer may step down or step up thevoltage received from the charging station to a voltage level suitable for the electric vehicle energy storage device within the vehicle assembly.

[0086] FIG. 2A shows a configuration diagram of a electric vehicle assembly with seperate onboard charging and wireless charging. The assembly 200A contains an OBC system 202 and a WC system 204. The OBC system 202 is able to electrically couple to an AC grid system 206 (i.e. a generator, public grid, portable generator, etc.) for a power supply through wiring containing a terminal at both ends. The PFC 208 receives AC from the AC grid system 206 and reduces the phase shift between the supplied voltage and current, thereby reducing the reactive power (i.e. wasted energy) and bringing the power factor closer to 1.

[0087] The PFC 208 may be a delta-connected capacitor bank, a star-connected capacitor bank, or contain active elements (i.e., diodes and switches) such as boost PFC, bridgeless boost, totem pole PFC, etc.

[0088] The inverter 210 receives the corrected power as DC and converts it into AC with a desired frequency using a series of switches. The inverter 210 may be a single phase or three phase inverter, depending on the load and / or magnetic coupling system used in the circuit. The transformer 212 receives the AC from the inverter 210 and transfers the AC from the primary winding to the secondary winding by inducing a magnetic field which transfers flux from the primary winding to the secondary winding thereby generating an induced voltage within the secondary winding. The transformer 212 may be a step-down transformer which reduces the voltage received from the AC grid to an amount that can be used to safely charge the EV battery 218.

[0089] The resonant network 214 may reduce the impedance within the power supply such that the current supplied from the resonant network is maximized. The resonant network 214 may tune the frequency of the incoming power to the resonance frequency of the circuit. The resonant network 214 may use a combination of resistors, capacitors and inductors to store the energy, provided by the transformer 212, in a state of oscillation depending on the desired resonant frequency. The resonant network 214 may be an S-S, LCC-S, LCC-LCC or S-LCC circuit in either series or parallel.

[0090] The rectifier 216 converts the AC into DC through the use of diodes, such as through a full bridge rectifier. The rectifier 216 provides the converted DC power supply as an output of the OBC system 202. The OBC system 202 is coupled to the EV battery 218, which allows the EV battery 218 to receive a charge from the DC power supply.

[0091] The WC system 204 in the assembly 200A is electrically coupled to a wireless ground assembly 220. The wireless ground assembly 220 acts to transfer power from the AC grid 206 to the WC system 204. The wireless ground assembly 216 contains a PFC 208 and inverter 210. The inverter 210 is coupled to a wireless charger transmitter 224 and receiver 226. The wireless charger receiver 226 is coupled to a resonant network 214 which stores the energy at the desired resonant frequency, the resonant network 214 is coupled to a rectifier 216 which converts the AC power supply to DC. The rectifier 216 provides a DC power supply as an output of the WC system 204, and the WC system 204 supplies the power to the EV battery 218 for charging. Due to the assembly 200A lacking integration between the WC 204 and OBC 202 systems, there is a duplication of electrical and mechanical components, adding to the weight, complexity, and inefficiencies within the charging environment.

[0092] A schematic of a proposed integrated EV charging system is shown in FIG. 2B. The OBC and WC share some electrical and mechanical components, and they both operate at a high switching frequency between 50 and 150 kHz. The integrated system 200B contains an integrated WC and OBC network 228 which contains a shared wireless charger receiver 230, a shared resonant network 232 and a shared rectifier 234. The shared wireless charger receiver 230 may be any one of a split-phase circular, rectangular, double-D, tripolar or bipolar magnetic coupler. The shared resonant network 232 tunes the frequency of the incoming power to the resonance frequency of the circuit. The shared resonant network 232 may use a combination of resistors, capacitors and inductors to store the energy, provided by the shared wireless charger receiver 230, in a state of oscillation depending on the desired resonant frequency. The shared resonant network 232 may be an S-S, LCC-S, LCC-LCC or S-LCC circuit in either series or parallel, these are all possible variations of the proposed embodiments that are contemplated. The shared rectifier 234 converts the AC power supply to DC. The shared rectifier 234 provides a DC power supply as an output of the integrated WCand OBC network 228, the WC and OBC network 228 provides the DC power supply to the EV battery 218 for charging.

[0093] The similarity within the integrated WC and OBC network 228 results in a comparable frequency response of the filters and resonant tanks. The integrated system 200B as seen in FIG. 2B, offers numerous benefits over traditional systems. By reducing the overall size and weight of the charging system, sharing components results in a cost-effective and efficient solution. Furthermore, the integration allows users to switch effortlessly between wired and wireless charging, resulting in greater convenience. The proposed integration can share electrical components such as resonant inductors, resonant capacitors, rectifiers 234, PCBs, connectors, contactors, and cables. In addition to the shared electrical components, the integrated system 200B can share mechanical components between the OBC and WC such as, but not limited to, the enclosure, heatsinks, thermal pads, cold plate, and the like.

[0094] In some embodiments, the wireless ground assembly 220 may be a parking spot in a residential or commercial parking station. In another embodiment, the wireless ground assembly 220 may be located within a manufacturing or shipping facility at a position where vehicles such as loaders or other heavy machinery often park while waiting for a next task. In some embodiments, the wireless ground assembly 220 may be within a drone carrying case or landing pad.

[0095] In some embodiments, system 200B may utilize WC mode as the primary charging method, with OBC being available as a secondary option when WC is not available or undesirable. For example, when system 200B is used for an autonomous vehicle, such as a taxi, passenger vehicles, vacuum cleaner, arial drone, etc., the primary basis of charging may be WC mode, allowing the autonomous vehicle to return to a charging station without a user having to be present after the battery has been depleted below a pre-determined threshold. However, due to the integration of the OBC within the system 200B, an autonomous vehicle would have the ability to receive a charge from a mechanically connected charging source (i.e. through a terminal) if it was incapable of returning to the charging station.

[0096] For example, in a warehouse setting, ground charging stations could be placed at common locations at which vehicles (forklifts, cranes, transport trucks) are typically requiredto spend large amounts of times (loading docks, common pathways) such that the vehicles could be charged as it operates. In another example, in a transport setting, ground charging stations could be located along common shipping routes such that vehicles could be charged either as they drive along the route (i.e. the ground charging stations are under the road) or at major stopping points (i.e. off ramp locations).

[0097] In some circumstances, it is preferable to use OBC mode for charging, even if it would be possible to return to a charging station. For example, when the vehicle battery has reached below a minimum threshold it may be preferable to use the OBC mode in order to preserve battery health due to the potential damage which can be caused by exposing the depleted battery to the higher power provided in WC mode.

[0098] Therefore, it would be understood that the integrated system 200B may be configured to prioritise wireless charging while permitting an integrated OBC system which generates minimal to no magnetic field leakage due to the split-phase design of the receiver coils 230.

[0099] FIG. 3A shows a circuit diagram of a proposed split-phase rectangular (or circular) receiver coil layout for use in integration of an onboard charger into a wireless charger, according to some embodiments. For example, one operationally valuable embodiment includes the rectangular split-phase magnetic coupler seen in FIG. 3A which is configured with a pair of parallel wire paths comprising at least two overlapping wire paths extending from the a and b terminals of the split-phase magnetic coupler. In operation, upon the split-phase magnetic coupler being aligned with the magnetic field of the wireless transmitter 224 (i.e., in WC mode), the induced current within the parallel wire paths flow in the same direction which generates a magnetic field coupling with the transmitter 224. Upon the split-phase magnetic coupler receiving current from the transformer 212 (i.e., in OBC mode), the current within the parallel wire paths flow in opposite directions, resulting in any magnetic field generated by one wire in the wire path being offset by an overlapping wire, with an opposing current direction, in the wire path. The a and b terminals of the split-phase magnetic coupler act as output terminals (or nodes) when the magnetic coupler receives current from the vehicle-side terminal (or node) of the transformer 212. The c terminal (or node) acts as an input node during OBCmode, and is electrically coupled to a vehicle side node (i.e., secondary side) of the transformer 212.

[0100] Single-phase circular, square, and rectangular coil configurations are similar; therefore, both can be modified based on the same principle. The proposed split-phase rectangular coil is shown in FIG. 3A. In FIG. 3A, lris the WC receiver 230 coil current and lsis the current of the secondary side of the OBC transformer 212.

[0101] The split-phase rectangular coil is shown in Error! Reference source not found. B during WC mode. In this mode, the transmitter 224 and receiver 230 coils of the WC magnetic coupler are close to each other. In WC mode, the transmitter 224 of the WC magnetic coupler generates a current that passes through the transmitter coil and creates an alternating magnetic field. Any magnetic field generated by the transmitter 224 side can pass through the receiver 230 coil, and it generates an induced voltage depending on the coupling factor between the two coils. As the two coils get closer or more aligned, the magnetic coupling factor increases. When the wireless charger coil current flows through the split-phase coil, the two branches of the winding (la=-lr and lb=lr) generate a magnetic field in the same direction and lc=ls=0. Therefore, it can generate magnetic coupling with the transmitter coil and transfer power wirelessly.

[0102] The split-phase rectangular coil is shown in Error! Reference source not found. C during OBC mode. While the system is operating in the OBC mode, the currents of the WC receiver 230 coil branches are in opposite directions la~lr and / &« / ,), which results in almost zero magnetic field generation (Br«0). The coil branches of the receiver 230 form overlapping branches where each branch of the magnetic coupler opposes another branch of the magnetic coupler to create a substantially symmetrical coil configuration. In some embodiments, the integrated system 200B may incorporate additional circuity and control software to balance the currents in the coils. This may result in a reduction in the magnetic field leakage, especially when there is asymmetry between the coil branches. For example, a current balancing circuit may be coupled to the coil branches to compensate for asymmetry of the coil windings. In some embodiments, the parallel coil branches can be twisted to reduce magnetic field emissions.

[0103] Compared to the magnetic couplers shown in FIGs. 1A-1 F, in which current passing through the coils will always generate a magnetic field, the proposed split-phase magnetic couplers incorporate a coil which acts as a return path which runs parallel with each turn of the coil, which may cancel the magnetic field generated by each turn. Therefore, the proposed split-phase magnetic couplers may be desirable for an integrated system 200B as the splitphase magnetic couplers may conduct current during OBC mode without generating a potentially dangerous level of magnetic field leakage.

[0104] Therefore, the system can work in OBC mode without violating SAE safety requirements and provide greater safety to individuals who may be proximate to the vehicle.

[0105] According to Ampere’s law B.d / =po / enc, where lenc is the total enclosed current in an imaginary path, c. When a closed loop path is considered, the total of length elements multiplied by the magnetic field in the direction of the length element is equivalent to the magnetic permeability multiplied by the electric current enclosed in the loop. In the proposed magnetic structure shown in Error! Reference source not found. C, at any arbitrary path around the wires of each turn, the sum of the enclosed current would be zero. Because the currents of the parallel wires are in opposite directions with equal amplitudes, according to Ampere’s law, the generated magnetic field is expected to be zero for each turn.

[0106] As an example, a single-phase OBC 302 and single split-phase rectangular magnetic coupler 304 of a series compensated wireless charger are integrated and the circuit topology and terminal connections are shown in Error! Reference source not found. D. Ground assembly 306 may transfer power PWPT through a magnetic field Mtrto the single split-phase rectangular magnetic coupler 304. Ground assembly 306 may be a parking spot or designated area in which an electric vehicle may stop, and the wireless charger transmitter 224 may be located above or below the vehicle to transfer power to the shared wireless charger receiver 230. In response to the magnetic field (Mtr), / a=- / / - and / b= / rsuch that power PWPT is transferred to the shared resonant network 232 and shared rectifier 234 before being supplied to the EV battery 218. The shared resonant network 232 may be a S-S, LCC-S, LCC-LCC or S-LCC. The shared rectifier 234 may be a full bridge containing four diodes arranged in a bridge configuration such that the output waveform provided to the EV battery 218 contains minimal fluctuations.

[0107] The AC power supply grid 308 may supply power to the single phase OBC 302 through the PFC 208. The PFC 208 supplies voltage VdCand current lpto the transformer 212. When in OBC mode, the transformer 212 may transfer power from the grid 308 to the integrated circuit 300 such that lsis roughly equal to lpsuch that Power POBC is transferred to the shared resonant network 232 and shared rectifier 234 before being supplied to the EV battery 218.

[0108] FIG. 4A shows a circuit diagram of a proposed split-phase double-D (DD) coil layout for integration of an onboard charger into a wireless charger. Single-phase bipolar and DD magnetic couplers are similar, the only difference is the overlap present in a bipolar magnetic coupler between the two interior side coils. Therefore, the same modification can be applied to both bipolar and DD magnetic couplers. As an example, FIG. 4A shows a simplified split- DD coil modified with a split-phase configuration. In FIG. 4A, / ris the WC coil current, and / sis the current of the secondary side of the OBC transformer 112 (i.e., la+lb+lc=0Y FIG. 4B shows the split-phase double-D coil layout in WC mode; the receiver 230 coil current enters terminal a (la=lr) and leaves the coil at terminal b ( b=-lr In this situation, the magnetic field generated by parallel branches will be in the same direction and generate in-phase magnetic fields (Br). FIG. 4C shows the split-phase double-D coil layout in OBC mode, the transformer current ( / s) enters at terminal c and divides between the two parallel branches with opposite flow directions. Therefore, in OBC mode, the sum of the magnetic field generated by the parallel branches is zero or substantially zero.

[0109] FIG. 5A shows a layout diagram of a modified split-phase bipolar three-phase magnetic coupler for integration of an onboard charger into a wireless charger, according to some embodiments. In this configuration, A 502, B 504, and C 506 are three phases of the receiver coil 104. When the system is operating in WC mode, the three-phase current with a 120° of electrical phase shift will flow through the magnetic coupler. The current directions and approximate magnetic field of the three-phase system at one instance (0=90°) are shown in FIG. 5B. The figure displays the direction of the current through arrows. The magnetic field generated outside the plane of the coils is represented by positive flux 508 and negative flux 510 in the Z-axis. In contrast, when the system operates in OBC mode, as seen in FIG. 5C, the currents of all phases are in phase and ideally generate identical magnetic fields.

[0110] Since there is an overlap between the coils, the magnetic flux sum on top of any point of the magnetic coupler is almost zero. Because each section overlaps with two halves of the other two phases. For example, the A+ section 502 is facing B- 504 and C- 506; assuming a clockwise current circulation in the A+ section 502, B- 504 and C- 506 currents are flowing counterclockwise. Since half of B- 504 and half of C- 506 are overlapping with A+ 502, the total generated flux is expected to be zero. Under some conditions, due to the width of the coil, manufacturing imperfection, and the distance of the coils from the ferrite surface, not all the magnetic flux may be canceled. In this case, the layout is in partial symmetry which may result in some magnetic field leakage during OBC mode operation. Therefore, it may be desirable to implement additional circuity and control software to balance the currents in the coils within the integrated system 200B. This may result in a reduction in the magnetic field leakage, especially when there is asymmetry between the coil branches. For example, a current balancing circuit may be coupled to the coil branches to compensate for asymmetry of the coil windings.

[0111] SIMULATION RESULTS

[0112] The wireless charging receiver 230 magnetic coupler was modified, as proposed above, to be a split-phase rectangular coupler (as shown in FIGs. 3A-3C) capable of being integrated with an OBC system. In order to study the operation of the integrated split-phase rectangular coupler system, a finite element analysis (FEA) was performed, and the results are shown in FIGs. 6A, 6B, 6C, 6D. In FIGs. 6A, 6B, 6C, 6D, the terminals are extended to +Z and excited at plane Z=500mm. In this case, the rated power of the WC and the OBC are set to 6.6 kW.

[0113] FIG. 6A shows the magnetic field density 600A in the ferrite plates and magnetic field vector in the YZ plane when the system 200B is operating in WC mode. As expected for a unipolar magnetic coupler, the magnetic field direction appears to be emanating out from the center of the coil and returning from the outside. The magnetic field density 600B at 2 cm from the surface of the coil is shown in FIG. 6B when the system 200B is operating in WC mode. The highlighted layout of the coil is shown in this figure for better visibility. It is apparent from the high magnetic field density that there is a coupling between the transmitter 104 and receiver coil 106. FIG. 6C shows the magnetic field density 600C and vector in the ferriteplates and air when the system 200B is operating in OBC mode. It can be seen that the magnetic field density is significantly lower than the WC mode in the ferrite plates due to antiparallel current flow. The magnetic field density 600D at a distance of 2 cm from the surface of the split-phase rectangular magnetic coupler in OBC mode is shown in FIG. 6D. It can be seen that the magnetic field emission is lower than 38 pT, which is according to SAE requirements for light-duty EV charging. In some embodiments, the parallel branches may be routed tightly or twisted to further reduce the difference between their inductance due to the increased length of the parallel wire paths. Therefore, the total current is divided evenly between the parallel branches.

[0114] The wireless charging receiver 230 magnetic coupler was modified, as proposed above, to be a split-phase DD coupler (as seen in FIGs. 4A-4C) capable of being integrated with an OBC system. In order to study the operation of the integrated split-phase DD coupler system, a finite element analysis (FEA) was performed, and the results are shown in FIGs. 7A, 7B, 7C, 7D. In FIGs. 7A, 7B, 7C, 7D, the terminals are extended to +Z and excited at plane Z=500mm.

[0115] FIG. 7A shows the magnetic field density 700A on the ferrite plate 102 and magnetic field vector in the XZ plane when the system 200B is operating in WC mode. The excitation current for the transmitter 224 and receiver 230 are 20 A and 25 A, respectively. As expected, the magnetic field vector exits from one side and enters the other side of the DD coil. The magnetic field density 700B at a distance of 2 cm from the surface of the coil in the XY-plane when the system 200B is operating in WC mode is shown in FIG. 7B. In this figure, the coil layout is highlighted for better visibility. In the next step, the coils are excited in OBC mode wherein la+lb=-lc and / a= / b=- / c / 2. The magnetic field density 700C and its vector in OBC mode are shown in FIG. 7C. The magnetic field density 700D at a distance of 2 cm from the surface of the coil in the XY-plane when the system 200B is operating in OBC mode is demonstrated in FIG. 7D. It can be seen that the magnetic field density is within a range that is deemed safe according to the SAE safety requirements. Therefore, the proposed integrated wireless charging system 200B using a modified split-phase DD magnetic coupler is suitable for use without posing any potential risks or hazards associated with magnetic field exposure.

[0116] The wireless charging receiver 230 magnetic coupler was modified, as proposed above, to be a split-phase three-phase bipolar coupler (as seen in FIGs. 5A-5C) capable of being integrated with an OBC system. Simulation results of WC and OBC modes are presented in FIGs. 8A, 8B, 8C, 8D. In this case, the rated power of the wireless charger and the onboard charger are 50 kW and 6.6 kW, respectively.

[0117] FIG. 8A shows the magnetic field density 800A in the ferrite plates and magnetic field vector in the YZ plane when the system 200B is operating in WC mode. In the center of the magnetic coupler, magnetic field density is higher than the corners of the magnetic coupler. Moreover, the magnetic field vector leaves from a positive coil section, A+ 502, B+ 504, and C+ 506, passes through the air, and returns to the plane of the corresponding negative coil section A- 502, B-504, and C- 506. This is due to using a bipolar layout. Therefore, it can be seen that there are two poles per phase on the magnetic coupler plane.

[0118] The magnetic field density 800B at 2 cm from the surface of the coil is shown in FIG. 8B when the system 200B is operating in WC mode. It can be seen that the magnetic field density is high in the center, and it has a similar shape as the magnetic field density on the ferrite plane. Therefore, if any metal object appears in this region, it can cause heating of the metallic object. Moreover, it can be observed that the magnetic field is homogeneously distributed over the study plane. This is due to the fact that the three-phase system created a symmetrical magnetic field distribution.

[0119] FIG. 8C shows the magnetic field density 800C and vector in the ferrite plates and air when the system 200B is operating in OBC mode. In this case, all the phase windings are in sync and generate the same magnetic field. This system behaves as a single-phase multipole structure. In this mode, the magnetic flux generated by each section of the positive coil section, A+ 502, B+ 504, and C+ 506, leaves the coil plane, passes through the air, and returns to the negative coil sections A- 502, B- 504, and C- 506.

[0120] The magnetic field density 800D at a distance of 2 cm from the surface of the magnetic coupler in OBC mode is shown in FIG. 8D. It can be seen that when the system 200B is operating in OBC mode, the magnetic field density at a distance from the surface is low, as compared to the density seen in WC mode in FIGs. 8A-8B.

[0121] The integrated system may be suitable for autonomous vehicles and electric vehicles with high power ratings. When used for an autonomous vehicle, such as a taxi, passenger vehicles, vacuum cleaner, aerial drone, etc., the primary basis of charging will be the WC mode, allowing the autonomous vehicle to return to a charging station after the battery has been depleted below a pre-determined threshold. However, due to the integration of the OBC within the system, an autonomous vehicle would have the ability to receive a charge from a mechanically connected charging source (i.e. through a terminal) if it was incapable of returning to the charging station.

[0122] When used for an electric vehicle with a higher power rating then most consumer vehicles, such as a bus, transport vehicles, cranes, forklifts, or other vehicles used in shipping and warehouse operations, the use of the full bridge rectifier along with the voltage splitting within the integrated system allows the WC mode to transfer a high voltage source which thereby reduces downtime and allows the vehicles to return to operation with a full charge in a relatively short amount of time. For example, in a warehouse setting, ground charging stations could be placed at common locations at which vehicles (forklifts, cranes, transport trucks) are typically required to spend large amounts of times (loading docks, common pathways) such that the vehicles could be charged as it operates. In another example, in a transport setting, ground charging stations could be located along common shipping routes such that vehicles could be charged either as they drive along the route (i.e. the ground charging stations are under the road) or at major stopping points (i.e. off ramp locations).

[0123] In some circumstances, it is preferable to use OBC mode for charging, even if it would be possible to return to a charging station. For example, when the vehicle battery has reached below a minimum threshold, such as 30% charge, it may be preferable to use the OBC mode in order to preserve battery health due to the potential damage which can be caused by exposing the depleted battery to the higher power provided in WC mode.

[0124] In other circumstances, while WC mode may be preferred, there may be an urgent need for charging through OBC mode. For example, if an electric vehicle is unable to return to a ground charging station prior to the battery being completely or substantially depleted, the electric vehicle may be able to have a power source brought to its location (such as a portable generator) which can charge the electric vehicle in OBC mode such that the battery is returnedto a power level sufficient to arrive at a ground charging station to receive the remaining charge through WC mode.

[0125] As can be seen from the above examples, the integrated system may be designed for the WC mode to be the primary charging method. The high voltage which is capable of being provided by the integrated system in WC mode allows for more efficient and timely charging without the need to have a person present at the time of charging to connect physical terminals. However, the integrated circuit provides the possibility of OBC mode at a reduced cost and complexity, due to the shared components and improved safety, which can be used as a fail safe if an electric vehicle would otherwise be unable to reach a ground charging station.

[0126] The wireless charging mode may be compatible with any standard wireless ground assembly 220 for wireless charging, allowing the proposed integrated system to be used across varying geographic areas and industry sectors.

[0127] The proposed integrated system may be sold as a stand-alone component which can be implemented into a vehicle assembly at the time of manufacture. Further, in some operational configurations, the proposed integrated system may be sold as a retro-fit which can provide an integrated charging system to a vehicle assembly which has either an existing WC system, an existing OBC system, or a separate WC and OBC system already present within the electric vehicle. In some embodiments, the proposed system can include active control components, such as active switches, which are controlled by a pulse-width modulator configured within the system. Active control schemes may include controlling active components within the resonant network, the connection between the OBC transformer and magnetic coupler, or the rectifier.

[0128] It is understood that the term “shared” is intended to describe the joint use of certain electrical components within the system between both the OBC and WC systems. For example, the shared resonant network 232 operates to control the frequency of both the current from the transformer 212 and the induced current received from the wireless transmitter 224.

[0129] The system 200B may be operable with one or more power sources, including one or more of an AC grid connection, a portable power unit / generator, or an energy storage device. The wireless ground assembly 220 and transformer 212 may be connected to the same or separate power sources when charging the battery 218. In a preferred embodiment, the wireless ground assembly 220 is a ground based transmitter pad and connected to a first AC grid network connection, and the transformer 212 is electrically coupled through physical terminals to a second AC grid network connection.

[0130] Applicant notes that the described embodiments and examples are illustrative and non-limiting. Practical implementation of the features may incorporate a combination of some or all of the aspects, and features described herein should not be taken as indications of future or existing product plans. Applicant partakes in both foundational and applied research, and in some cases, the features described are developed on an exploratory basis.

[0131] The term “connected” or "coupled to" may include both direct coupling (in which two elements that are coupled to each other contact each other) and indirect coupling (in which at least one additional element is located between the two elements).

[0132] Although the embodiments have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the scope. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification.

[0133] As one of ordinary skill in the art will readily appreciate from the disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. Accordingly, the present embodiments are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

[0134] As can be understood, the examples described above and illustrated are intended to be exemplary only.

Claims

WHAT IS CLAIMED IS:

1. An integrated charging system for an electric vehicle capable of transferring power wirelessly and through direct charging using at least one split-phase magnetic coupler, the system comprising: a wireless transmitter within a wireless ground assembly and having at least one coil for producing a magnetic field when the wireless transmitter is electrically coupled to a first power source; a transformer having a vehicle-side node coupled to the at least one split-phase magnetic coupler and transmitting a current across the vehicle-side node when the transformer is electrically coupled to a second power source; a shared receiver electrically coupled to the transformer and inductively coupled to the wireless transmitter, the shared receiver includes the at least one splitphase magnetic coupler receiving an induced current from the wireless transmitter and having a first node for receiving the current from the vehicle-side node of the transformer, and at least two output nodes coupled to overlapping branches of the split-phase magnetic coupler; a shared resonant network electrically coupled to the two output nodes; and a shared rectifier electrically coupled between the shared resonant network and an energy storage device, the energy storage device configured to store power received from at least one of the wireless transmitter and transformer; wherein the shared receiver forms a coupling point with the transformer and the overlapping branches reduce the magnetic field leakage when receiving current from the vehicle-side node of the transformer.

2. The charging system of claim 1 , wherein the at least one split-phase magnetic coupler is a three-phase magnetic coupler: wherein upon the three-phase magnetic coupler being aligned with the magnetic field, the induced currents within the overlapping branches have a phase shift of 120°; and wherein upon the three-phase magnetic coupler receiving current from the transformer, the current in within the overlapping branches have a 0° phase shift.

3. The charging system of claim 1 , wherein the overlapping branches of the at least one split-phase magnetic coupler are formed from a pair of parallel wire paths comprising at least two wires beginning at the at least two output nodes and merging at the first node.

4. The charging system of claim 3, wherein: upon the split-phase magnetic coupler being aligned with the magnetic field, the induced current within the two wires of the parallel wire paths flow in the same direction; and upon the split-phase magnetic coupler receiving current from the transformer, the current within the two wires of the two parallel wire paths flow in opposite directions.

5. The charging system of claim 4, wherein the split-phase magnetic coupler is at least one of a uni-polar, multi-polar, circular, rectangular and double-D coil structure.

6. The charging system of any one of claims 1-5, wherein the shared resonant network comprises at least one of a resonant inductor and resonant capacitor.

7. The charging system of any one of claims 1-6, further comprising a current balancing circuit electrically coupled to the at least one split-phase magnetic coupler.

8. The charging system of claim 7, wherein the shared charging assembly contains shared physical components comprising at least one of an enclosure, printed circuit boards, connectors, contacts, heatsinks, thermal pads, cold plate, and cables.

9. The charging system of any one of claims 3-4, wherein the two wires of the parallel wire path are twisted to form a helical shape, wherein the helical shape increases the length of the parallel wire path.

10. The charging system of any one of claims 1-9, wherein the energy storage device is a battery, and the battery, shared receiver, shared resonant network, shared rectifier and transformer are housed in a shared charging assembly within an electric vehicle assembly.

11. A method for integrated charging of an energy storage device, the energy storage device being charged by current provided from at least two power sources, the method comprising:generating a magnetic field through a coil of a wireless transmitter within a wireless ground assembly when the wireless transmitter is receiving power from a first power source; generating a current flow across a vehicle side node of a transformer when the transformer is receiving power from a second power source; aligning at least one split-phase magnetic coupler of the shared receiver with the magnetic field of the wireless transmitter, and / or transferring current, through the vehicle side node of the transformer, to the at least one split-phase magnetic coupler comprising overlapping branches; wherein the wireless transmitter generates an induced current in the split-phase magnetic coupler, and the vehicle side node of the transformer is electrically coupled to a first node of the split phase magnetic coupler; providing a shared resonant network and shared rectifier coupled to the shared receiver in series, the shared resonant network electrically coupled to two output nodes on the shared receiver; and transferring at least one of the induced current and the current from the shared rectifier to the energy storage device; wherein the shared receiver forms a coupling point with the transformer and the overlapping branches reduce the magnetic field leakage when receiving current from the vehicle-side node of the transformer.

12. The method of claim 11 , wherein the at least one split-phase magnetic coupler is a three- phase magnetic coupler: wherein upon the three-phase magnetic coupler being aligned with the magnetic field, the induced currents within the overlapping branches have a phase shift of 120°; and wherein upon the three-phase magnetic coupler receiving current from the transformer, the current within the overlapping branches has a 0° phase shift.

13. The method of claim 11 , further comprising forming the overlapping branches of the at least one split-phase magnetic coupler from a pair of parallel wire paths forming at least two wires beginning at the at least two output nodes and merging at the first node.

14. The method of claim 13, wherein: upon the split-phase magnetic coupler being aligned with the magnetic field, the induced current within the two wires of the parallel wire path flow in the same direction; and upon the split-phase magnetic coupler receiving current from the transformer, the current within the two wires of the two parallel wire path flow in opposite directions.

15. The method of claim 14, wherein the split-phase magnetic coupler is one of a uni-polar, multi-polar, circular, rectangular and double-D coil structure.

16. The method of any one of claims 11-15, wherein the shared resonant network comprises at least one of a resonant inductor and resonant capacitor.

17. The method of any one of claims 11-16, further comprising controlling the magnetic field leakage from the split-phase magnetic coupler through a current balancing circuit electrically coupled to the at least one split-phase magnetic coupler.

18. The method of claim 15, wherein the shared charging assembly contains shared mechanical components comprising at least one of an enclosure, printed circuit boards, connectors, contactors, heatsinks, thermal pads, cold plate, and cables.

19. The method of any one of claims 13-14, further comprising twisting the two wires of the parallel wire path to form a helical shape, wherein the helical shape increases the length of the parallel wire path.

20. The method of any one of claims 11-19, wherein the energy storage device is a battery, and further comprising housing the battery, shared receiver, shared resonant network, shared rectifier and transformer are housing in a shared charging assembly within an electric vehicle assembly.

21. A non-transitory computer readable medium, storing machine interpretable instruction sets, which when executed by a processor, cause the processor to perform a method according to any one of claims 11-20.

22. A vehicle drivetrain comprising the charging system of any one of claims 1-10.

23. An electric vehicle comprising the vehicle drivetrain of claim 22.

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