Integrated wireless and on-board charging system

Abstract

A series of integrated on-board and wireless chargers are presented in various embodiments. The charger is adapted for both in-vehicle charging and wireless charging using the same rectifier, thereby significantly reducing cost, weight and volume, which is an important consideration of improving the employment of power technology in the case where an energy storage device needs to be charged. Changes relating to other shared resonant component and connection variants are also presented.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is a non-provisional application of U.S. Application No. 63 / 447,033, filed February 20, 2023, entitled “INTEGRATED WIRELESS AND ONBOARD CHARGING SYSTEMS,” and claims all benefits, including priority, of the application, which is incorporated by reference in its entirety. TECHNICAL FIELD

[0003] Embodiments of the present disclosure relate to the field of charging electronic devices, and more specifically, embodiments relate to apparatuses, systems, and methods for integrated wireless and onboard charging systems. BACKGROUND

[0004] Wireless power transfer (WPT) and wired onboard chargers (OBC) are the two most predominant methods of Level 1 and Level 2 EV charging (i.e., charging of traction batteries when power is below 20 kW). WPT is a useful mechanism that provides a convenient mechanism for charging (e.g., no need to plug in), and, for example, WPT can be embedded into a parking spot. OBC infrastructure allows vehicles to perform charging operations and reduces some of the need for certain charging infrastructure components.

[0005] Typically, OBC is a converter that is fully embedded in the vehicle and contains two stages. The first stage is a power factor correction (PFC) converter that is responsible for meeting the total harmonic distortion (THD) requirements for interconnection with the grid while converting the incoming alternating current (AC) to direct current (DC). The second stage is a traditional galvanically isolated DC-to-DC conversion stage. At the DC-to-DC stage, the DC voltage produced by the PFC stage is converted back to AC, conducted through a galvanically isolated transformer, and then rectified again to DC to power the traction battery.

[0006] WPT solutions can be described as having the same stages as OBC, with the difference being that the DC-to-AC conversion in the PFC stage and the isolated DC-to-DC converter is located outside the vehicle. In addition, galvanic isolation is replaced by a combination of components that are inside and not inside the vehicle, instead of a galvanically isolated transformer. The transmit coil operates similarly to the primary of a transformer, while the receive coil operates similarly to the secondary side of a transformer. Like OBC, WPT solutions also have a rectifier connected downstream of the galvanically isolated stage.

[0007] A technical deficiency of WPT and OBC systems is that the systems add weight, complexity, and expense due to the need for various electronic components.

[0008] Accordingly, improved methods are desirable. SUMMARY

[0009] A series of integrated on-board and wireless charger circuits and corresponding electronic systems are presented in various embodiments. The charger is adapted to use the same rectifier for both on-board charging (OBC mode charging) and wireless charging (WC mode charging), thereby significantly reducing cost, weight, and volume, which are important considerations for adoption of power technology where energy storage devices need to be charged. For example, the complexity of charging infrastructure and components is a major consideration for developing electric vehicles, as cost, weight, and volume can impact vehicle range and operational characteristics, and saving cost can improve or speed up adoption of "green" technology, which can have environmental benefits, such as reducing climate impact by reducing dependence on combustion-based technology.

[0010] Using the same rectifier for OBC mode charging and WC mode charging can be challenging, as technical issues related to undesirable interaction of OBC and WC can arise, which can create performance and safety issues.

[0011] One of the major challenges of integrating OBC and WC is the goal of not producing any magnetic field on the wireless receiving coil when the system is operating in OBC mode. From a performance perspective, the circulating current in the coil produces more conduction and magnetic core losses when the system is operating in OBC mode.

[0012] Also, when the system is operating in WC mode, the OBC transformer current and voltage should be considered to avoid incurring additional losses. Therefore, it can be considered to use additional circuits such as relays to disconnect the two systems. However, this can impact the reliability and cost of the system.

[0013] A good integration solution can operate in OBC mode without producing a magnetic field on the wireless charger coil and minimize the circulating current in the wireless charger circuit. Also, when operating in WC mode, the transformer and OBC inverter losses are not increased. Furthermore, an ideal integration solution should be more commercially competitive than traditional solutions. Therefore, it is desirable to make minor modifications to the circuit topology without requiring additional components to minimize cost.

[0014] While some solutions have been presented to combine on-board charging with wireless charging, other solutions require undesirable modifications to the topology of the on-board charger to prevent harmful interaction. Therefore, these approaches have faced challenges in terms of practical feasibility.

[0015] The proposed solution described herein uses the common mode current path on the secondary side of the isolation transformer of the on-board charger as the path for wireless charging. In other words, the wireless charger output current is split into two or more parallel paths to the load (i.e. the currents are in phase). From the OBC circuit perspective, these parallel paths are considered as common mode current paths.

[0016] The proposed solution uses the differential mode power transfer path for the on-board charger (i.e. the currents are out of phase leaving the winding terminals of the transformer). In alternative embodiments, the common mode current path is used for the WC and the differential mode path is used for the OBC. In yet another alternative embodiment, the allocation of the common mode or differential mode paths can be dynamic to, for example, optimize the efficiency of the power transfer.

[0017] For example, in a single phase OBC with a single phase transformer, the power of the OBC circuit is transferred to the load by a differential mode current. This differential mode current circulates in the secondary side winding of the transformer. In other words, the current leaves from the top terminal of the transformer winding, circulates through the load, and returns to the secondary side winding from the bottom terminal. If a wireless charger is connected to the middle terminal of the secondary side winding of the transformer and the midpoint of the output DC link. In this case, the output current of the wireless charger will split into two equal currents and flow in opposite directions to the secondary side winding of the transformer. In other words, the wireless charger current flows out from both ends of the secondary side winding and returns from the midpoint of the DC link. It can thus be said that from the OBC circuit perspective, the power of the wireless charger is transferred through a common mode path. As previously mentioned, in alternative embodiments, the common mode and differential mode can be swapped between the WC and OBC circuits.

[0018] The isolation transformer can be single phase or multi-phase configuration. Furthermore, in some embodiments (but not necessarily in all embodiments), the proposed topology integrates the resonant components of the receiving side of the wireless charging system into the OBC circuit. The integrated circuit can be configured to ensure soft switching conditions within a wide range of loads. Integrating the resonant elements into the on-board charger can take advantage of the leakage inductance of the transformer. Thus, the proposed integrated solution shares the resonant components and / or the rectifier stage between the on-board charger and the wireless charger to save cost and space. As described herein, in some proposed variants, the integrated resonant components are possible, but not all embodiments must have this functionality. In some proposed variants, only the rectifier is shared.

[0019] In particular, the rectifier downstream of the electrical isolation transformer of the OBC is used as the rectifier of the wireless charger (WC), thus eliminating the need for a dedicated rectifier. The method is adapted to exploit the basic symmetry to ensure decoupling between the two systems to facilitate safe operation. The symmetric circuit is formed by connecting the wireless charger output terminals to the midpoint or neutral point of the secondary winding of the OBC transformer and to the midpoint of the DC link capacitor. The OBC circuit operates in differential mode and the WC operates in common mode (and vice versa). Therefore, there is no parasitic interaction between the two systems. A further advantage of the proposed method is that no major modifications to the OBC are required, such as the inclusion of additional relays or challenging fine-tuning.

[0020] Many variant embodiments are proposed in the method herein.

[0021] In some embodiments, there are variations with an APU integrated to the transformer. The output of the APU is connected to an auxiliary battery of the vehicle, for example a 12V lead-acid battery, whose negative terminal is usually connected to the chassis, while the input of the APU is connected to the main traction battery. Therefore, electrical isolation is usually considered a feature of the APU, which is achieved by the presence of an electrical isolation transformer in the circuit, with the aim of preventing the traction battery from being connected to the vehicle chassis, thus improving safety.

[0022] Taking into account the costs associated with an additional transformer, it is also advantageous to take advantage of the transformer present in the OBC to avoid the need for a dedicated transformer within the APU, thus reducing the overall system cost. This can be achieved by using a transformer with three ports, as shown in the proposed circuit, which can be an active bridge with integrated low-voltage auxiliary circuit, with one port connected to the output of the PFC, one port connected to the OBC rectifier and the WC, and the third port connected to the rectifier stage of the APU.

[0023] In some embodiments, there are variations without an APU integrated to the transformer. These embodiments can be suitable for specific applications, as by separating the APU and OBC implementation, it relaxes the constraints by not having to meet the requirements of both the APU and the OBC in a single component, at the expense of a higher bill of materials cost, such as an additional electrical isolation transformer. In these embodiments, the OBC and APU are integrated and work in a way that does not interfere with each other. In some embodiments, the APU can be separate from both the OBC and WC implementation.

[0024] In some embodiments, there are variations with the use of a single-phase transformer. Single-phase transformers are used for low-power applications where the wire diameter and switching current rating are within reasonable limits. In addition, single-phase transformers are easier to build and manufacture.

[0025] In some embodiments, there are variations using multiphase (e.g., three-phase) transformers. Multiphase transformers are typically suitable for high-power applications to reduce the rated current of the transformer windings and inverter switches. Furthermore, they can improve the fault tolerance of the system.

[0026] In some embodiments, the wireless coil can be directly connected to the rectifier. Directly connecting the wireless coil means that the wireless charger's receiving circuitry is connected in parallel with the secondary side circuitry of the vehicle charger. The advantage of a direct connection is that it can be a simpler implementation and requires no modifications to the circuitry. However, when the vehicle charger is operating, current will flow through the wireless charging circuitry in parallel, generating a magnetic field on the receiving coil. This can pose safety concerns for charged bodies and metal objects around the receiving coil.

[0027] Furthermore, circulating current introduces more losses and reduces OBC efficiency. Similarly, when the wireless charger is operating, it can induce voltage on the primary side of the OBC transformer and generate high voltage on the DC link, which may damage the inverter switches and capacitors.

[0028] In some embodiments, the wireless coil may be indirectly connected to the rectifier, but independently of the electrical isolation transformer. Indirect connection of the wireless coil means that a disconnect circuit, such as a relay, may be included between the wireless coil and the rectifier. One advantage of connecting the wireless coil to the rectifier via a relay is that the relay can be actuated to ensure that the wireless coil is not accidentally energized due to OBC operation.

[0029] In some embodiments, the wireless coil can be directly or indirectly connected to an electrical isolation transformer and another point in the system. Connecting to the electrical isolation transformer without using terminals coupled to the rectifier allows for functional decoupling between the WC and OBC; for example, the OBC power is associated with the differential-mode current on the secondary coil of the OBC, while the WPT is associated with the common-mode current on the secondary coil.

[0030] To clarify the terminology, both solutions are connected to a transformer, but the difference is that one of the solutions is not directly connected to the rectifier, and therefore does not require a relay isolator. Thus, connecting the coil to the system without using terminals coupled to the rectifier allows the OBC to operate while the WC coil is connected to the system, and therefore the wireless coil can be connected without the need for a relay to disconnect it.

[0031] In some embodiments, the wireless receiving coil can be connected to the rectifier via a relay, which allows the WC to be disconnected from the system. The disadvantage of these embodiments is the need for the aforementioned relay, while the advantage is that it ensures the wireless coil is not energized during OBC operation (i.e., wired power transmission) due to being disconnected.

[0032] In some embodiments, wired and wireless power are decoupled (e.g., do not interfere with each other). Decoupling is accomplished by designing the system such that each of the (wired and wireless) power supplies is associated with (e.g., indicating the current modes) a given pair (differential and common mode) of coils or windings. For example, the secondary side of an OBC's electrical isolation transformer may contain two windings, where the sum of the currents in the windings in the direction that causes the magnetic flux to flow through the core is called the differential mode, and the difference in currents in the windings is called the common mode.

[0033] In some embodiments, wired power is associated with the differential mode (DM) at the transformer, while wireless power is associated with the common mode (CM) at the transformer. Differential mode means that the current direction is opposite for each secondary winding portion. Common mode means that the current direction is the same for each secondary winding portion. In this topology, an example configuration involves connecting the wireless charging coil to a point on the OBC transformer (e.g., the midpoint of the secondary side, but other points are possible) and a point on the load-side capacitor (e.g., the midpoint of the load capacitor divider, such that the capacitance division between the midpoint and the rectifier is equal, but connections that result in unequal capacitance division are also possible). For this embodiment, it is advantageous that wired power is associated with the DM at the transformer, while wireless power is associated with the CM at the transformer, because the DM and CM are decoupled. Therefore, in some embodiments, it may be possible to process the wired charging power with DM current without generating any CM current, and thus without exciting the wireless coil. Furthermore, the CM current through the transformer's secondary side used to operate the wireless charger does not generate magnetic flux, does not interfere with the primary winding of the OBC's electrical isolation transformer, and the transformer's rated current remains constant.

[0034] In some embodiments, wired power is associated with the common mode at the transformer, and wireless power is associated with the differential mode at the transformer. For this embodiment, the advantage of connecting the wired power to the common mode (CM) at the transformer means that one terminal on the secondary side of the transformer is connected to a point on the receiving coil (e.g., the midpoint, but other points are also possible), and the other terminal is connected to a point on the load-side capacitor (e.g., the midpoint of a capacitor divider, making the load-side capacitance equal, but connections causing unequal capacitance are also possible). The advantage of connecting the wireless power to the DM at the transformer means that the wireless charger's receiving circuitry is connected to the rectifier. In this embodiment, during WPT operation, the receiving WC does not generate CM current or voltage, and therefore does not activate the OBC circuitry. This is a result of the decoupling between the CM and DM currents.

[0035] Wired power is associated with differential mode at the transformer, and wireless power is associated with common mode at the transformer. This can refer to a structure where the electrical isolation transformer has a separate coil connection and the wireless coil is connected there, as referred to as a Class I solution for single-phase applications. Conversely, the statement "wired power is associated with common mode at the wireless coil, and wireless power is associated with differential mode at the wireless coil" refers to a structure where the coil has a separate coil connection, as referred to below as a Class III structure.

[0036] Practical examples of modular chargers can be considered as onboard components for vehicles, such as retrofitting existing vehicles, upgrading charging systems, or creating complete vehicles with the necessary components. Retrofitting is considered in cases where the vehicle has an OBC but lacks wireless charging circuitry at the time of manufacture. An improved charging system implemented by adding charging functionality is envisioned where the added WPT circuit does not include a rectifier, but instead utilizes the rectifier of the existing OBC to reduce retrofitting costs. In the initial design phase, improved vehicles are envisioned where the WPT circuit is designed to utilize the OBC's rectifier instead of a dedicated rectifier, thereby reducing costs. Vehicles can include cars, trucks, ships, aircraft, autonomous vehicles such as autonomous aircraft (e.g., drones), and any equipment responsible for moving itself and / or potentially additional loads (e.g., people, goods).

[0037] Furthermore, alternative embodiments are also considered, which may include, but are not limited to, any portable device that includes an energy storage device (such as a battery) that requires charging and can benefit from a combination of OBC and WPT. For example, this could include a large portable battery pack for camping or emergencies, which could benefit from improved charging.

[0038] Control methods and approaches related to operating the aforementioned apparatus are also considered, as well as machine instruction products / articles, such as non-transitory machine-readable media storing machine instructions that can be executed on the processor or control circuitry of the aforementioned magazine to perform the operating methods. Attached Figure Description

[0039] The accompanying drawings illustrate embodiments by way of example. It should be clearly understood that the descriptions and drawings are for illustrative purposes only and are intended to aid in understanding.

[0040] Embodiments will now be described by way of example only with reference to the accompanying drawings, in which:

[0041] FIG. 1 This is a block diagram of an example device having an energy storage device and components thereon, according to some embodiments.

[0042] FIG. 2This is a schematic diagram of an electric vehicle (EV) charging system according to some embodiments.

[0043] Figure 3A and FIG. 3B The diagram shows example OBCs with and without resonant networks according to some embodiments. FIG. 3C This is a circuit diagram showing the topology of an OBC (On-Board Rectifier) ​​utilizing a single-phase transformer and a passive diode bridge rectifier according to some embodiments. FIG. 3E , FIG. 3F and FIG. 3G In some embodiments, the DC-to-DC stage utilizes a three-phase electrical isolation transformer.

[0044] FIG. 4 A and FIG. 4 B is a circuit diagram showing the operation of the system in different modes according to some embodiments. FIG. 4 A illustrates the operation of a system in OBC mode according to some embodiments, and FIG. 4 B shows the system operating in WC mode.

[0045] FIG. 5 A and FIG. 5 B is a circuit diagram showing a YY-type variant of the system proposed according to some embodiments. FIG. 5 A shows a system in OBC mode, and FIG. 5 B shows the system in WC mode.

[0046] FIG. 6A and FIG. 6B This is a set of waveforms showing example simulation results according to some embodiments.

[0047] FIG. 7 This is a schematic diagram 700 showing a description of an experimental apparatus for displaying an integrated system and control according to some embodiments.

[0048] FIG. 8A and FIG. 8B The reference tracking performance (Io) is shown under different load conditions.

[0049] FIG. 9A and FIG. 9B The reference tracking performance (Io) is shown under different load conditions.

[0050] FIG. 10A and FIG. 10B The reference tracking performance (Io) is shown under different load conditions.

[0051] FIG. 11 and FIG. 12 The efficiency of the closed-loop system relative to the output current is shown under different load (battery) voltages according to some embodiments.

[0052] FIG. 13A , FIG. 13B , FIG. 13C , FIG. 13D , FIG. 13E The wireless charging coil (I) is shown under different load conditions according to some embodiments. r0 The leakage current on the surface.

[0053] FIG. 14A , FIG. 14B , FIG. 14C , FIG. 14D , FIG. 14E The wireless charging coil (I) is shown under different load conditions according to some embodiments. r0 The leakage current on the surface.

[0054] FIG. 15A , FIG. 15B The closed-loop waveform of a wireless charging system connected to a 420V load is shown according to some embodiments. Detailed Implementation

[0055] As described in further detail below, a method is proposed that combines wireless power transfer (WPT) and on-board charger (OBC). The proposed method overcomes certain problems associated with combining the two methods, such as using the same rectifier for both OBC and WPT. Numerous variations and sub-variants are also proposed, for example, using different combinations of connection types, couplings, and common-mode and differential-mode configurations (or their dynamic allocation modes / paths to reduce losses or improve efficiency).

[0056] All these changes represent different envisioned approaches to improving the operation of the combined charger mechanism, and the combined charger can be practically implemented by retrofitting existing drive systems or configuring new drive systems for integration into improved vehicles. Improved drive systems can provide additional wireless charging capabilities, a convenient and desirable feature that, for example, can increase the adoption of green technologies.

[0057] Experimental results are also provided to illustrate the operation of the example embodiments, where the OBC comprises a full-bridge inverter, a single-phase transformer, and a diode bridge. In the provided example, the wireless charger receiver circuit is connected to the center tap on the secondary side of the transformer. The OBC input is powered by a constant DC voltage, and the output is regulated using inverter phase shift or frequency. The wireless charging circuit is powered by a variable DC voltage instead of a variable voltage PFC. The system output is connected to an electronic load (or a resistive load) and tested in constant resistance and constant voltage modes. The WPT operates during both wireless charging mode (WC mode) and on-board charging mode (OBC mode). Operational efficiency is an important performance metric, and the proposed integration of WC and OBC modes should ideally be designed to minimize the impact on the operational efficiency of either WC or OBC mode. For example, the proposed symmetrical design in some embodiments can help prevent the operation of one mode from affecting the efficiency of the other.

[0058] FIG. 1 This is a block diagram of an example device having an energy storage device and components thereon, according to some embodiments.

[0059] exist FIG. 1 In this example, for illustrative purposes, the example device 100 is a vehicle 150, but not all embodiments require that the device suitable for wireless charging and on-board charging be a vehicle 150 that may be part of the drivetrain 120. For example, a non-vehicle example device that combines wireless charging and on-board charging is a portable battery pack. Device 100 may include an on-board charger 102 and a wireless charging circuit 104, and these may be configured to charge energy storage devices, such as energy storage device 106 and auxiliary energy storage device 108. Standalone devices 100 and devices 100 integrated into other portable electronic devices (such as, but not limited to, drivetrain 120 and vehicle 150) are contemplated. FIG. 1 As shown, the vehicle charger circuit 102 and the wireless charging circuit 104 can share components.

[0060] In some embodiments, an additional control switch or control circuit is provided that manages charge characteristics and is configured to dynamically allocate common-mode current paths or differential-mode power transfer paths for the on-board charger or wireless charger. The control switch or control circuit can switch allocation based on polling (e.g., polling) of both methods, selecting the most efficient (e.g., highest power transfer) path, or it can be configured to try an alternative path when efficiency falls below a predetermined threshold. This provides a flexible approach to handling non-ideal situations and taking into account variations.

[0061] One example method utilizes the common-mode current path on the secondary side of the isolation transformer of an onboard charger as the path for wireless charging of the device.

[0062] Wireless power transfer (WPT) and wired on-board chargers (OBCs) are the two primary methods for Level 1 and Level 2 EV charging (i.e., charging the traction battery at power levels below 20kW). Typically, an OBC is a converter fully integrated into the vehicle and consists of two stages. The first stage is a power factor correction (PFC) converter responsible for meeting the total harmonic distortion (THD) requirements for grid interconnection while converting the input alternating current (AC) to direct current (DC). The second stage is a conventional electrically isolated DC-to-DC conversion stage. In the DC-to-DC stage, the DC voltage generated by the PFC stage is converted back to AC, conducted through an electrically isolated transformer, and then rectified again to DC to power the traction battery.

[0063] The WPT solution can be described as having the same stages as the OBC, except that the PFC stage and the DC-to-AC conversion in the isolated DC-to-DC converter are located outside the vehicle. Furthermore, electrical isolation is replaced by a combination of components both inside and outside the vehicle, rather than an electrical isolation transformer. The transmitting coil operates similarly to the primary winding of a transformer, while the receiving coil resembles the secondary side. Like the OBC, the WPT solution also has a rectifier connected downstream of the electrical isolation stage.

[0064] Given the similarity of components, a solution is proposed to utilize OBC or other existing components to implement a portion of the wireless charger (WC), thereby reducing the capital costs associated with WC.

[0065] In [1], an integrated boost converter and WC solution was proposed. However, this approach requires a relay to switch between operating modes, which may increase production costs. In [2,3], the integration of the receiver side of a wireless charging system with the secondary side of the OBC transformer was proposed. In this approach, frequency tuning is used to decouple the OBC circuit from the WC circuit.

[0066] The solutions proposed in [2,3] require a fundamental change to the topology of the OBC to prevent harmful interactions between the OBC and the receiving coil, and the solutions are very sensitive to changes in nominal parameters, making the system impractical.

[0067] In [4], a novel integration of WC and OBC based on a magnetic coupler for a wireless charging system was proposed. However, this method requires the use of a relay and generates a magnetic field when the system operates in OBC mode.

[0068] Similarly, in [5], the OBC and WC share the same receiving circuit. In this method, the receiving coil acts as a transformer tightly coupled to the primary side of the OBC and loosely coupled to the transmitting side of the WC system.

[0069] The main drawback of the topology [5] is that a relay is required on the primary side of the OBC to open the circuit when the system is operating in WC mode; and a magnetic field is generated on the wireless receiving coil when the system is operating in OBC mode.

[0070] As described in the various embodiments herein, a series of WC solutions are proposed to reduce the capital cost of the WC by utilizing components present in the OBC. Specifically, the rectifier downstream of the OBC's electrical isolation transformer is used as the WC's rectifier, thereby eliminating the need for a dedicated rectifier. The solutions proposed herein advance the current technology by requiring no major modifications to the OBC, such as including additional relays or challenging fine-tuning.

[0071] Conversely, the solution utilizes fundamental symmetry to ensure decoupling between the two systems, thereby ensuring safe operation. In the context of this disclosure, fundamental symmetry means that both the OBC or WC systems use CM or DM, and this specifically allows for decoupling by ensuring that no circulating current or minimal current caused by the other system flows to each system, and thus safe operation is achieved because no magnetic field is generated or damaged during OBC system operation.

[0072] FIG. 2 A schematic diagram of an electric vehicle (EV) charging system is shown. Due to the similar high switching frequencies (50-150kHz) in both systems, the receiver side of the OBC and WC chargers shares several common components. Integrating and optimizing these components for both wired and wireless charging modes results in cost and size savings compared to conventional systems. A brief overview of the operational characteristics and variations of the system will be presented in the following sections. FIG. 2 Two figures 200 are used as examples. FIG. 2 The image above shows an actual variant that includes shared components.

[0073] As mentioned above, the connection between the OBC and the power grid is accomplished via the PFC level. The solution presented in this report is independent of PFC configuration. A dividing line is shown between external components and onboard components.

[0074] DC-to-DC stages include inverters, electrical isolation transformers, and rectifiers. Several topologies are available for the electrical isolation transformers, as well as the inverters and rectifiers. In some OBC embodiments, the transformer may be single-phase, thus limiting the inverter and rectifier to being correspondingly single-phase as well. In some other embodiments, the isolation transformer may be three-phase, configured in YY, YΔ, ΔY, or ΔΔ configurations, thereby limiting the inverter and rectifier to three-phase. Different phase changes are provided because, at high power stages, moving to a multiphase system is preferred. Furthermore, different configurations of the three-phase transformer can be used to reduce the rated current of the windings or the value of the resonant capacitor, depending on application requirements.

[0075] Another source of variation in the OBC solution lies in the rectifier downstream of the isolation transformer. If unidirectional charging capability is sufficient, the rectifier can be implemented using passive diodes, which are cheaper than active semiconductor switches and do not require gate drive circuitry. Conversely, if bidirectional power transfer is required, active switches can be used as semiconductors, with additional functionality to reasonably control costs. Specifically, different topologies can be used for the rectifier stage, such as diode full-bridge

[16] , center-tapped

[18] , voltage multipliers [19,20], current multipliers [21-25], and active full-bridge rectifiers [26,27] or semi-active bridge rectifiers. The main difference between full-bridge and center-tapped rectifier topologies lies in the rated number and components of the semiconductor devices. Trade-offs should be made between these parameters depending on the application. A voltage multiplier circuit can supply twice the voltage on the secondary side of the OBC transformer to the load, thus allowing for a lower primary side voltage. Furthermore, it saves two semiconductors from the rectifier compared to a full-bridge rectifier. However, the rated current of the transformer secondary winding will be twice that of a full-bridge configuration. Similarly, a current doubler circuit can supply twice the rated current of the winding to the load, but it requires two additional inductors. In active rectifiers, diodes are replaced by active switches such as MOSFETs or IGBTs. This increases the freedom to control the load and improves system efficiency. However, it increases the overall cost of the system. To save costs, in semi-active rectifiers, half, but not all, of the diodes are replaced by active switches. However, this configuration is only suitable for unidirectional power transmission.

[0076] For illustrative purposes, some embodiments of the proposed solution are shown, as well as sample OBC topologies compatible with a specific integrated WPT solution.

[0077] Figure 3A shows a single-phase OBC (both active and passive rectifiers) without a resonant network, implemented as a diode bridge. The proposed solution is embodied in a WPT coil and its associated capacitor resonant network connected between the center point of the capacitive divider associated with the traction battery and the midpoint of the secondary coil of the OBC's electrical isolation transformer. The only modification required for the OBC is the introduction of this midpoint connection into the secondary coil.

[0078] FIG. 3B A single-phase OBC with a capacitive resonant network is shown. As shown in Figure 3A, the rectifier downstream of the electrical isolation transformer is implemented using a passive diode bridge. Unlike that shown in Figure 3A, FIG. 3B The OBC illustrated herein includes a capacitor network. Here, the same set of capacitors (with capacitance C) rs It is used as the resonant network for OBC and WPT, thereby reducing impedance during wired and wireless charging operations and improving efficiency by providing soft switching.

[0079] In the various proposed embodiments, the selection of two methods is considered. Specifically, the methods may further include selecting between different methods, which may be done, for example, during configuration or manufacturing. The selection depends on the design of the WC system. Generally, the LCC topology is preferred for wireless charging in EV applications because it offers higher efficiency and better tolerance to load and mutual inductance variations. Therefore, Figure 3A is better for EV applications. (It is worth noting that comparisons under other assumptions can be challenging, therefore other methods and / or experimental approaches are considered.)

[0080] In Figure 3A and FIG. 3B In wireless charging, the power is associated with the common-mode current flowing through the electrically isolated secondary coil. In contrast, the power in OBC charging is associated with the differential current flowing through the electrically isolated secondary coil. The decoupling nature of the differential-mode and common-mode degrees of freedom of the coils allows for decoupling operations in wired or wireless charging safely without interfering with unused portions of the circuitry.

[0081] When the system operates in OBC mode, current flows out from the top terminal of the secondary winding and returns from the bottom terminal. Therefore, according to Kirchhoff's laws, no current flows through the midpoint connection of the winding connected to the wireless charging circuit. In this case, the current in the transformer's secondary winding flows in opposite directions, hence this power transfer method is called differential mode operation. Since the current flowing to the wireless charger circuit is zero, no magnetic field is generated on the receiving coil, ensuring safe operation of the system in OBC mode.

[0082] When the system operates in WC mode, the wireless charger current enters from the midpoint of the secondary winding of the transformer and exits from both the bottom and top terminals of the secondary winding. Therefore, the current is in phase; hence, this power transfer method is called common-mode operation. In this mode, the current in each section of the secondary winding of the OBC transformer generates opposite but equal-amplitude induced voltages on the primary side of the transformer winding. Therefore, ideally, the total induced voltage on the primary side of the transformer should be zero, which is desirable. Thus, the proposed system can operate in WC mode without interfering with or damaging the OBC circuitry.

[0083] exist FIG. 3C In this process, the OBC utilizes a single-phase transformer and a passive diode bridge rectifier, as shown in Figure 3A and... FIG. 3B The scenario described involves the OBC secondary coil connected between the midpoint of the receiving coil in the wireless charging system and the midpoint of the capacitive voltage divider associated with the traction battery. As described above, the midpoint is shown as an illustrative example, but other points may also be considered. This applies to all references below concerning the midpoint.

[0084] In this configuration, wired charging power is associated with the common-mode current flowing through the WC, while wireless power transfer is associated with the differential-mode current flowing through the WC. The decoupling nature of the coil's differential-mode and common-mode degrees of freedom allows for safe and uninterrupted decoupling of wired or wireless charging without interfering with unused portions of the circuitry. Decoupling is safer and results in less loss because it ensures that only the intended operating system (e.g., wired or wireless) is powered at any given time, while systems not intended for operation remain unpowered, even though they share components.

[0085] exist FIG. 3E , FIG. 3F and FIG. 3G In this configuration, DC-to-DC transmission utilizes a three-phase electrical isolation transformer. In these cases, the secondary side of the electrical isolation transformer is Y-connected, enabling the use of a neutral point. In the three-phase configuration, wired power transmission is associated with the differential-mode current flowing through the secondary side of the electrical isolation transformer. Conversely, wireless power is associated with the common-mode current flowing through the secondary side of the transformer (i.e., the transformer's neutral current).

[0086] The rest of this section will explain the operating principles.

[0087] Single-phase Type I

[0088] Figure 3A shows a variation of the proposed integration method.

[0089] In this system, the OBC consists of a full-bridge inverter, a single-phase transformer, and a diode bridge. The wireless charger receiver circuit is connected to the center tap on the secondary side of the transformer. In this configuration, the leakage inductance of the secondary winding of the OBC transformer can be used to form an LCC compensation network for the wireless charging system. Therefore, in this integrated configuration, the diode bridge and resonant inductor are shared.

[0090] FIG. 4 A illustrates system operation in OBC mode. In this mode, the induced voltage on the secondary side of the transformer is symmetrical, and the center tap of the transformer remains balanced with the midpoint of the DC capacitor on the load side. Therefore, no current flows through the WC path (i.e., IC). w =0 and I a =I b Furthermore, no magnetic field will be generated on the WC receiving coil.

[0091] FIG. 4 B illustrates the system's operation in WC mode. In this mode, the wireless charger generates a voltage in the opposite direction on the secondary winding of the transformer. Therefore, the current in the secondary winding flows in the opposite direction, and its amplitude is half that of the wireless charging path current (i.e., IC). a =-I b =I w / 2). In this case, the induced voltage on the primary side of the transformer is almost zero.

[0092] Single-phase Type II

[0093] In this configuration, the series resonance of the wireless charging system is shared with the OBC circuit. This resonant capacitor also helps provide zero-voltage switching (ZVS) for the inverter switches. Therefore, sharing the rectifier stage and resonant capacitor between both the OBC and WC saves costs.

[0094] Single-phase Type III

[0095] The topology of a single-phase OBC with an integrated wireless charger is shown in FIG. 3C In this system, the receiving coil of the wireless charger is divided into two parts, and one of the terminals on the secondary side of the OBC transformer is connected to the midpoint. The other terminal of the OBC transformer is connected to the midpoint of the DC link capacitor. The OBC utilizes the wireless charger's LCC resonant network, which can provide different voltage gains (at different frequencies) and soft-switching functionality. In this configuration, the OBC charges the battery through a voltage doubler rectifier, and the wireless charger uses a full-bridge rectifier. The advantage of this approach is that the rated current of the wireless charger's receiving coil is half that of single-phase Type I and Type II topologies.

[0096] When the OBC is operating, the currents flowing in the wireless coil section are in opposite directions. Therefore, the sum of the magnetic fields generated on the receiving coil (below the vehicle) will be zero. When the WC is operating, the currents in the receiving coil section are in the same direction. Therefore, no current will flow through the midpoint of the WC receiving coil to reach the OBC circuit. Thus, the two systems are decoupled from each other at the two operating points. FIG. 3C In the middle, a resonant inductor L was added. b Instead of a series-parallel compensation network, an LCC compensation network is formed. The LCC network behaves differently; it operates as a current source suitable for battery charging applications. This provides improvement because the current source limits the output current. Therefore, in the event of an output short circuit, the converter output current will be limited to the design value. Thus, the circuit will not be damaged due to a short-circuit fault. Operating as a current source limits the output current according to the adjustment of the resonant network. Furthermore, it helps the battery charger converter operate in a constant current charging mode.

[0097] YYI type

[0098] In this system, the wireless charger (L) r The receiving coil is connected to the LCC compensation network. The two resonant capacitors are not integrated into the on-board charger, but the resonant inductor is integrated with the leakage inductance of the secondary side of the OBC transformer. Furthermore, a diode bridge is shared between the two systems.

[0099] exist FIG. 3D In this circuit, the OBC circuit is similar to any conventional isolated dual active bridge (DAB) or isolated phase-shifted DC-DC converter. In this circuit, when the OBC circuit is operating, energy is transferred from the AC grid to the circuit via a power factor correction (PFC) converter. The PFC stage generates a stable DC voltage to power the high-frequency inverter. As shown in Figure 3A), the inverter configuration can be either a full-bridge or a half-bridge. Furthermore, different numbers of pins can be used for the inverter to construct an interleaved circuit.

[0100] It should be noted that any number of legs (single leg, 3 legs, 6 legs, 9 legs, 12 legs, etc.) can be provided to balance the multiphase system.

[0101] Using an interleaved configuration offers several advantages, including lower rated units, better thermal management, improved fault tolerance, and reduced voltage and current ripple. This diagram illustrates a three-pole interleaved inverter (120-degree phase shift) as an example.

[0102] FIG. 5 A and FIG. 5 B shows respectively FIG. 3D The proposed system shown operates in both OBC and WC modes. (See details...) FIG. 5 A andFIG. 5 B. Wired power transmission is associated with a linear combination of the current differences between any two given windings of the secondary winding, which magnetically couples the primary and secondary coils. In contrast, wireless power is associated with the neutral current on the secondary side of the transformer, which is the sum of the currents in all three windings of the transformer's secondary side, i.e., the CM current. Therefore, wired and wireless power transmission are magnetically decoupled. Specifically, operation of one system cannot energize the other.

[0103] When the circuit is operating in OBC mode, the sum of the currents at the neutral point on the secondary side of the transformer is zero; therefore, no current will flow through the WC receiving circuit (i.e., I). w =0). Whenever the system is operating in WC mode, the wireless charger receiving coil (L r An induced voltage will be generated on the secondary side of the OBC transformer, which generates a current (Io) flowing to the neutral point of the secondary side of the OBC transformer. w Then, this current is divided into three branches (I). a =I b =I c =I w / 3), flows to the rectifier and charges the battery.

[0104] It is important to note that allowing current to flow in the secondary winding of the OBC transformer induces a voltage on the primary side of the OBC transformer. If the OBC inverter switch is in open-circuit mode, the primary voltage will charge the PFC DC link capacitor through the inverter switch's body diode. However, this situation only lasts until the DC link voltage reaches the induced voltage in the transformer's primary winding. After reaching a steady state, the current flowing in the primary side of the transformer will reach zero (i.e., I0). A =I B =I C =0).

[0105] The main advantage of this configuration is its topology compatibility with existing traditional OBC topologies. Furthermore, the control of this circuit can be performed similarly to any traditional OBC and WC. However, more components can be integrated to save further costs. Additionally, due to the use of a phase-shifted OBC, ZVS is limited. ZVS limitation is important because ZVS reduces switching losses and thus improves inverter efficiency. Furthermore, ZVS helps reduce EMI noise generated by the inverter.

[0106] YYII-Y type

[0107] The YYII configuration is shown in FIG. 3EIn this circuit, series compensation is used for the wireless charging system. The series capacitors are also moved from the neutral point path to each branch. When the system is operating in OBC mode, the circuit is a secondary-side compensated resonant converter. Compared to phase-shifted topologies, this circuit can provide ZVS operation over a wider load range. Furthermore, soft switching results in better efficiency and lower EMI noise. The operating principle of this circuit is similar to a YY I-type configuration. This configuration can help reduce the size of the required capacitor bank. It should be noted that the rated voltage of the resonant capacitor bank will remain the same as in a conventional series-compensated WC.

[0108] YY connection II-Δ type

[0109] The YY II-Δ configuration is shown in FIG. 3F In this topology, the capacitors are connected in a Δ configuration. Therefore, the required capacitance (C) rΔ This is equivalent to 1 / 3 of the compensation of a Y-type connection

[16] . Of course, the rated voltage for this configuration is higher than that of a Y-type connection. However, any of these topologies can be chosen depending on application requirements, optimization results, and component availability. FIG. 3F In the middle, the resonant capacitor C r With L r Series capacitors are added to form a series LC compensation network for the wireless receiving circuit. Without the resonant capacitor Cr, the efficiency of the wireless power transmission system would be greatly reduced. FIG. 3F The method described in the paper improves efficiency and maximizes transmittable power while reducing coil current.

[0110] Δ-Y connection type I

[0111] The ΔYIII type configuration is shown in FIG. 3G In this topology, the primary winding of the transformer is connected in a delta configuration. This helps to reduce the primary winding current. This is useful because smaller wire diameters (which are cheaper) can be used for the primary winding. Additionally, PCB windings can be used in planar transformer designs.

[0112] Simulation results

[0113] In this indicative simulation example for a practical application, it is assumed that the rated loads of both the OBC and WC are 6.6kW. The wireless charging system is operating at 85kHz (according to SAE2954). The wireless charging coil is rectangular, with dimensions of 640 × 508 mm. 2 A ferrite block is placed beneath the transmitting coil to reduce magnetic field leakage and improve system efficiency. Several proposed integrated topologies are simulated as examples, and the results are presented in this section. Other variations are possible, and these are shown as non-limiting illustrative guidelines.

[0114] FIG. 6A and FIG. 6B The simulation results of a single-phase Type I integrated system are shown. The compensation network is a two-sided LCC resonant network tuned at 85 kHz. It can be seen that, as... FIG. 6A As shown, when the system is operating in wireless charging mode, the OBC primary winding current (I) p The value is zero. Furthermore, it can be seen that the current on the secondary side of the OBC transformer is balanced and equal to half of the wireless circuit output current (I). w =2×I a =2×I b Similarly, when operating in OBC mode, such as FIG. 6B As shown, there is no path through the wireless charging circuit (I) where no current flows. w =0). In this case, the current on the secondary winding depends on the load current and the transformer turns ratio.

[0115] In some embodiments, the DC-to-DC stage of the OBC may employ a single-phase transformer, wherein the transformer secondary coil comprises two windings wound around the same magnetic core, wherein the terminals of each winding are connected together and connected to a conductor that indicates the current and / or voltage of the wireless receiving coil, wherein two additional terminals of the two windings comprising the single-phase transformer secondary coil are connected to a rectifier, wherein the traction battery is connected in parallel to a capacitive voltage divider, and wherein another terminal of the combined wireless receiving coil and compensation network is connected to the midpoint of the capacitive voltage divider.

[0116] In some embodiments, the DC-to-DC stage of the OBC may employ a single-phase transformer, wherein the transformer secondary coil comprises two windings wound around the same magnetic core, wherein the terminals of each winding are connected together and connected to a conductor that indicates the current and / or voltage of the wireless receiver coil, wherein the additional two terminals of the two windings comprising the single-phase transformer secondary coil are connected to a rectifier, wherein the traction battery is connected in parallel to a capacitive voltage divider, wherein another terminal of the combined wireless receiver coil and compensation network is connected to the midpoint of the capacitive voltage divider, wherein the tertiary coil of the single-phase transformer serves as part of the APU.

[0117] In some embodiments, the DC-to-DC stage of the OBC may employ a three-phase transformer, wherein the transformer secondary coil comprises three windings wound around the same magnetic core, wherein the terminals of each winding are connected together and connected to a conductor that indicates the current and / or voltage of the wireless receiving coil, wherein the additional three remaining terminals of the three windings comprising the three-phase transformer secondary coil are connected to a three-phase rectifier, wherein the traction battery is connected in parallel to a capacitive voltage divider, and wherein another terminal combining the wireless receiving coil and the compensation network is connected to the midpoint of the capacitive voltage divider.

[0118] The following sections describe the experimental results used in the example experimental setup.

[0119] One variation of the proposed integration method is the single-phase Type I topology currently under review. In this system, the OBC consists of a full-bridge inverter, a single-phase transformer, and a diode bridge.

[0120] The wireless charger receiver circuit is connected to the center tap on the secondary side of the transformer. A 6.6kW integrated wireless and vehicle-mounted charger is constructed, and the overall setup used in this experiment is shown below. FIG. 7 The specifications of the experimental setup are listed in Table I.

[0121] FIG. 7 This is a schematic diagram 700 showing a description of an experimental apparatus for displaying an integrated system and control according to some embodiments.

[0122] Table I: Specifications of integrated wireless and on-board charging systems.

[0123]

[0124] The OBC's input is powered by a constant DC voltage, and the output is regulated using inverter phase shift or frequency. The wireless charging circuitry is powered by a variable DC voltage, rather than a variable voltage PFC.

[0125] The system output is connected to an electronic load (or a resistive load) and tested in constant resistance and constant voltage modes.

[0126] The on-board charging (OBC mode) and wireless charging of the experimental setup will now be described.

[0127] OBC mode

[0128] In this experiment, the closed-loop reference tracking of the OBC was studied. In this system, the controller changes the inverter phase shift (θ) and switching frequency (f) sw_OBC The output current is adjusted according to a reference. The required reference current values ​​are 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, and 18 A. The input DC voltage is set to 400 V, and the load voltage is set to 280 V, 350 V, and 420 V. Waveform and efficiency measurement results from the power analyzer are presented in... FIG. 8A , FIG. 8B , FIG. 9A , FIG. 9B and FIG. 10A , FIG. 10B middle.

[0129] In these figures 800A, 800B, 900A, 900B, and 1000A, 1000B, oscilloscope CH1 represents the OBC inverter voltage (V). inCH2 is the OBC inverter current (I) in CH3 is the load voltage (V) o or V bat ), and CH4 is the load current (I o or I bat ). U dc1 and I dc1 The diagram shows the input DC voltage and current in the power analyzer's attached diagram, while U... dc2 and I dc2 This represents the output voltage and current. It can be seen that the phase angle of the OBC inverter current lags behind the OBC inverter voltage, indicating zero-voltage switching (ZVS). Furthermore, as expected, the closed-loop system can track the reference output current, and the system exhibits good efficiency at different operating points.

[0130] FIG. 8A and FIG. 8B The reference tracking performance (Io) is shown under different load conditions (280V-1A, 280V-10A).

[0131] FIG. 9A and FIG. 9B The reference tracking performance (Io) is shown under different load conditions (350V-2A, 350V-12A).

[0132] FIG. 10A and FIG. 10B The reference tracking performance (Io) is shown under different load conditions (420V–4A, 420V–8A).

[0133] FIG. 11 and FIG. 12 Figures 1100 and 1200 show the measured efficiency of the closed-loop system relative to the output current under different load (battery) voltages (280V, 350V, 420V) according to some embodiments.

[0134] It should be noted that the actual measurement results are displayed as points in the graph, and the dashed line is the calculated best-fit curve. It can be seen that under different load voltages (V... bat The proposed integrated system achieves an efficiency exceeding 94% under full load conditions. Furthermore, at a 420V load, the system achieves a peak efficiency of 98.3%. Therefore, it can be concluded that the proposed integration does not affect the efficiency of the OBC.

[0135] FIG. 11 The closed-loop system efficiency relative to the output current (Io) is shown according to some embodiments at different load voltages (280V, 350V, 420V).

[0136] FIG. 12The closed-loop system efficiency relative to output power (Pout) is shown according to some embodiments at different load voltages (280V, 350V, 420V).

[0137] To measure the leakage current of the wireless receiver coil in OBC mode and capture the relevant waveforms, the wireless coil was placed under fully aligned and 100mm offset conditions. The input DC voltage was set to 400V, and the load voltage was between 280, 350, and 420V. The output reference current was adjusted from 9A to 18A. To capture the necessary waveforms, an oscilloscope was used, with CH1 measuring the OBC inverter voltage, CH2 measuring the OBC inverter current, CH3 measuring the load current, and CH4 measuring the wireless coil current.

[0138] The experimental results when the receiver is fully aligned and the receiving coil is positioned with a deviation of 110 mm in the Y direction are presented as follows: FIG. 13A , FIG. 13B , FIG. 13C , FIG. 13D , FIG. 13E and FIG. 14A , FIG. 14B , FIG. 14C , FIG. 14D , FIG. 14E As can be seen, the leakage current is very low under different load conditions.

[0139] FIG. 13A , FIG. 13B , FIG. 13C , FIG. 13D , FIG. 13E The wireless charging coil (I) is shown under different load conditions (280V-9A, 280V-18A, 350V-9A, 350V-15A, 420V-9A) according to some embodiments. r0 The leakage current on the circuit is shown in Figures 1300A, 1300B, 1300C, 1300D, and 1300E.

[0140] FIG. 14A , FIG. 14B , FIG. 14C , FIG. 14D , FIG. 14E The wireless charging coil (I) is shown under different load conditions (280V-9A, 280V-18A, 350V-9A, 350V-15A, 420V-9A) according to some embodiments. r0 The leakage current on the circuit is shown in Figures 1400A, 1400B, 1400C, 1400D, and 1400E.

[0141] The wireless charging mode (WC mode) is now described. In this experiment, the grounding component (GA) of the wireless charger's input DC voltage is set to 550V, and a power of 3.3kW or 6.6kW is required for a 420V load. The system waveforms when operating in WC mode are shown below. FIG. 15A , FIG. 15B As can be seen, the OBC DC link voltage remains almost zero, indicating that the OBC is unaffected by the operation of the wireless charging system due to the symmetrical design of the transformer windings. The four channels of the waveform include the WC inverter voltage, WC inverter current, OBC DC voltage, and load current.

[0142] FIG. 15A , FIG. 15B Figures 1500A and 1500B show the closed-loop waveforms (3.3kW and 6.6kW when connected to a 420V load) of a wireless charging system connected to a 420V load according to some embodiments.

[0143] The applicant notes that the described embodiments and examples are illustrative and not restrictive. Actual implementations of the features may combine some or all of the aspects, and the features described herein should not be considered as indications of future or existing product plans. The applicant is involved in both basic and applied research, and in some cases, the features have been developed on an exploratory basis.

[0144] The term “connected” or “coupled to” can include direct coupling (where two elements coupled to each other are in contact with each other) and indirect coupling (where at least one additional element is located between the two elements).

[0145] Although embodiments have been described in detail, it should be understood that various changes, substitutions, and modifications can be made herein without departing from the scope. Furthermore, the scope of this application is not intended to be limited to the specific embodiments of the processes, machines, manufactures, material compositions, components, methods, and steps described in this specification.

[0146] As will be readily understood by those skilled in the art from this disclosure, existing or later-developed processes, machines, manufactures, material compositions, components, methods, or steps that perform substantially the same functions as those in the corresponding embodiments described herein or achieve substantially the same results as those in the corresponding embodiments described herein can be utilized. Therefore, the appended claims are intended to include such processes, machines, manufactures, material compositions, components, methods, or steps within their scope.

[0147] As you can understand, the examples described and shown above are intended to be illustrative only.

[0148] References

[0149] [1] M. Chinthavali, OCOnar, SLCampbell and LMTolbert, “Integrated charger with wirelesscharging and boost functions for PHEV and EV applications”, 2015 IEEE Transportation Electrification Conference and Expo (ITEC), June 14-17, 2015, pp. 1-8, doi:10.1109 / ITEC.2015.7165813.

[0150] [2] M. Elshaer, C. Bell, A. Hamid and J. Wang, “DC-DC Topology for Interfacing a Wireless Power Transfer System to an On-Board Conductive Charger for Plug-in Electric Vehicles”, IEEE Transactions on Industry Applications, pp. 1-1, 2021, doi:10.1109 / TIA.2021.3103700.

[0151] [3] M. Elshaer, C. Bell, A. Hamid and J. Wang, “Wireless Power Transfer System Integration with an On-Board Conductive Charger for Plug-in Electric Vehicles”, IEEE Energy Conversion Congress and Exposition (ECCE) 2020, 11-15 October 2020, pp. 5177-5184, doi:10.1109 / ECCE44975.2020.9235852.

[0152] [4] B. Vu, J. M. G. Gonzalez-Gonzalez, V. Pickert, M. Dahidah and A. Trivino, “A hybrid charger of conductive and inductive modes for Electric Vehicles”, IEEE Trans. Ind. Electron., pp. 1-1, 2020, doi:10.1109 / TIE.2020.3042162.

[0153] [5] Y. Zhang, Y. Wu, Z. Shen, W. Pan, H. Wang, J. Dong, X. Mao and X. Liu, “Integration of Onboard Charger and Wireless Charging System for Electric Vehicles with Shared Coupler, Compensation, and Rectifier”, IEEE Transactions on Industry Electronics, pp. 1-4, 2022, doi:10.1109 / TIE.2022.3204857.

[0154] [6] A. Khaligh and M. D'Antonio, “Global Trends in High-Power On-Board Chargers for Electric Vehicles”, IEEE Trans.Veh.Technol., Vol. 68, No. 4, pp. 3306-3324, 2019, doi:10.1109 / TVT.2019.2897050.

[0155] [7] S. Jeong, Y. Jeong, J. Kwon and B. Kwon, “A Soft-Switching Single-Stage Converter With High Efficiency for a 3.3-kW On-Board Charger”, IEEE Transactions on Industry Electronics, Vol. 66, No. 9, pp. 6959-6967, 2019, doi:10.1109 / TIE.2018.2877093.

[0156] [8] Stefan Ditze, Stefan Ehrlich, Nikolai Weitz, Marco Sauer, Frank Aβmus, Anne Sacher, Christopher Joffe, Christoph Seβler and Patrick Meiβner, “A High-Efficiency High-Power-Density SiC-Based Portable Charger for Electric Vehicles”, Electronics, Vol. 11, No. 12, p. 1818, 2022. [Online]. Available:

[0157] https: / / www.mdpi.com / 2079-9292 / 11 / 12 / 1818.

[0158] [9] Z. Fang, T. Cai, S. Duan and C. Chen, “Optimal Design Methodology for LLC Resonant Converter in Battery Charging Applications Based on Time-Weighted Average Efficiency”, IEEE Transactions on Power Electron, Vol. 30, No. 10, pp. 5469-5483, 2015, doi:10.1109 / TPEL.2014.2379278.

[0159]

[10] Tiago JCSousa, Delfim Pedrosa, Vitor Monteiro and Joao L. Afonso, “A Review on Integrated Battery Chargers for Electric Vehicles”, Energy, Vol. 15, No. 8, p. 2756, 2022. [Online]. Available at: https: / / www.mdpi.com / 1996-1073 / 15 / 8 / 2756.

[0160]

[11] CDViana, S.Semsar, M.Pathmanathan and PWLehn, “Integrated Transformerless EV Charger with Symmetrical Modulation”, IEEE Transactions on Industry Electronics, pp. 1-1, 2021, doi:10.1109 / TIE.2021.3127032.

[0161]

[12] S. Semsar, T. Soong and P. W. Lehn, “On-Board Single-Phase Integrated Electric Vehicle Charger With V2G Functionality”, IEEE Transactions on Power Electronics, Vol. 35, No. 11, pp. 12072-12084, 2020, doi:10.1109 / TPEL.2020.2982326.

[0162]

[13] Ruoyun Shi, Sepehr Semsa and Peter W. Lehn, “Constant Current Fast Charging of Electric Vehicles via a DC Grid Using a Dual-Inverter Drive”, IEEE Transactions on Industry Electronics, Vol. 64, No. 9, pp. 6940-6949, 2017, doi:10.1109 / tie.2017.2686362.

[0163]

[14] R. Hou and A. Emadi, “Applied Integrated Active Filter Auxiliary PowerModule for Electrified Vehicles With Single-Phase Onboard Chargers”, IEEE Transactions on Power Electronics, Vol. 32, No. 3, pp. 1860-1871, 2017, doi:10.1109 / TPEL.2016.2569486.

[0164]

[15] R. Hou and A. Emadi, “A Primary Full-Integrated Active Filter Auxiliary Power Module in Electrified Vehicles With Single-Phase Onboard Chargers”, IEEE Transactions on Power Electronics, Vol. 32, No. 11, pp. 8393-8405, 2017, doi:10.1109 / TPEL.2017.2650482.

[0165]

[16] C. Fei, R. Gadelrab, Q. Li and FCLee, “High-Frequency Three-Phase Interleaved LLC Resonant Converter with GaN Devices and Integrated Planar Magnetics”, IEEE J.Sel.Topics Power Electron, pp. 1-1, 2019, doi:10.1109 / JESTPE.2019.2891317.

[0166]

[17] C. Fei, FCLee and Q. Li, “High-Efficiency High-Power-Density LLC Converter With an Integrated Planar Matrix Transformer for High-Output Current Applications”, IEEE Transactions on Industry Electronics, Vol. 64, No. 11, pp. 9072-9082, 2017, doi:10.1109 / TIE.2017.2674599.

[0167]

[18] E. Orietti, P. Mattavelli, G. Spiazzi, C. Adragna and G. Gattavari, “Current sharing in three-phase LLC interleaved resonant converter”, 2009 IEEE Energy Conversion Congress and Exposition, 20-24 Sep 2009, pp. 1145-1152, doi:10.1109 / ECCE.2009.5316510.

[0168]

[19] S. Kim, B. Kim, B. Kwon and M. Kim, “An Active Voltage-Doubler Rectifier Based Hybrid Resonant DC / DC Converter for Wide-Input-Range Thermoelectric Power Generation”, IEEE Transactions on Power Electronics, Vol. 33, No. 11, pp. 9470-9481, 2018, doi:10.1109 / TPEL.2017.2788923.

[0169]

[20] M. Abbasi, R. Emamalipour, MAMCheema and J. Lam, “A Constant Frequency HighVoltage Gain Resonant Converter Module With Semi-Active Phase-Shifted Voltage Multiplier For MVDC Distribution”, IEEE Power Electronics Emerging and Featured Subjects, pp. 1-1, 2021, doi:10.1109 / JESTPE.2021.3088120.

[0170]

[21] U. Badstuebner, J. Biela, D. Christen and J. W. Kolar, “Optimization of a 5-kW Telecom Phase-Shift DC–DC Converter With Magnetically Integrated Current Doubler”, IEEE Transactions on Industry Electronics, Vol. 58, No. 10, pp. 4736-4745, 2011, doi:10.1109 / TIE.2010.2103536.

[0171]

[22] F. Grazian, T.B. Soeiro and P. Bauer, “Voltage / Current Doubler Converter for an Efficient Wireless Charging of Electric Vehicles with 400V and 800V Battery Voltages”, IEEE Transactions on Industry Electronics, pp. 1-11, 2022, doi:10.1109 / TIE.2022.3208582.

[0172]

[23] M. Xiong, H. Dai, Q. Li, Z. Jiang, Z. Luo and X. Wei, “Design of the LCC-SP Topology with a Current Doubler for 11kW Wireless Charging System of Electric Vehicles”, IEEE Trans. Transport. Electrific., pp. 1-1, 2021, doi:10.1109 / TTE.2021.3074007.

[0173]

[24] Lixin Shi, Alberto Delgado, Regina Ramos and Pedro Alou, “A Wireless Power Transfer System with Inverse Coupled Current Doubler Rectifier for High Output Current Applications”, IEEE Transactions on Industry Electronics, pp. 1-1, 2021, doi:10.1109 / tie.2021.3078350.

[0174]

[25] HZZBeh, MJNeath, JTBoys and GACovic, “An Alternative IPT Pickup Controller for Materials Handling using a Current Doubler”, IEEE Transactions on Power Electronics, Vol. PP, No. 99, pp. 1-1, 2018, doi:10.1109 / TPEL.2018.2801247.

[0175]

[26] P. Amiri, C. Botting, M. Craciun, W. Eberle and L. Wang, “Analytic–Adaptive LLC Resonant Converter SynchronousRectifier Control”, IEEE Transactions on Power Electronics, Vol. 36, No. 5, pp. 5941-5953, 2021, doi:10.1109 / TPEL.2020.3026374.

[0176]

[27] C. Fei, Q. Li and FCLee, “Digital Implementation of Adaptive Synchronous Rectifier (SR) Driving Scheme for High-Frequency LLC Converters With Microcontroller”, IEEE Transactions on Power Electronics, Vol. 33, No. 6, pp. 5351-5361, 2018, doi:10.1109 / TPEL.2017.2731942.

Claims

1. An apparatus for charging an energy storage device, the apparatus comprising: Onboard charger circuit; Wireless charger circuitry; The on-board charger circuit and the wireless charger circuit share a rectifier stage.

2. The device according to claim 1, wherein the vehicle charger circuit and the wireless charger circuit share a resonant component.

3. The apparatus of claim 2, wherein the resonant component on the receiving side of the wireless charging circuit is integrated into the vehicle charger circuit.

4. The apparatus of claim 2 or 3, wherein the resonant component includes at least one shared resonant network, and the shared resonant network reduces impedance during wired and wireless charging operation.

5. The apparatus according to any one of claims 1 to 3, wherein the on-board charger circuit includes an isolation transformer having a secondary side, and a common-mode current path on the secondary side serves as a path for wireless charging by the wireless charger circuit.

6. The apparatus according to any one of claims 1 to 3, wherein the on-board charger circuit includes an isolation transformer having a secondary side, and the differential mode current path on the secondary side serves as a path for wireless charging by the wireless charger circuit.

7. The apparatus of claim 5, wherein the isolation transformer is three-phase.

8. The apparatus according to any one of claims 6 and 7, further comprising an auxiliary power supply circuit also integrated into the isolation transformer.

9. The apparatus of claim 1, wherein the wireless charger circuit is directly connected to the rectifier stage.

10. The apparatus of claim 5, wherein the wireless charger circuitry is indirectly connected to the rectifier stage and is also independent of the isolation transformer.

11. The apparatus of claim 5, wherein the wireless charger circuit is directly or indirectly connected to the isolation transformer and another point in the system.

12. The apparatus of claim 11, wherein the wired and wireless power of the apparatus are decoupled.

13. The apparatus of claim 12, wherein the wired power transmission is associated with a differential-mode connection at the isolation transformer, and the wireless power transmission is associated with a common-mode connection at the isolation transformer.

14. The apparatus of claim 12, wherein wireless power transmission is associated with a differential-mode connection at the isolation transformer, and wired power transmission is associated with a common-mode connection at the isolation transformer.

15. The apparatus of claim 13, wherein the isolation transformer has a discrete coil connection.

16. The apparatus of claim 15, wherein the wireless coil of the wireless charger circuit is connected to the isolation transformer at the discrete coil connection.

17. The apparatus of claim 15, wherein a conductor indicating the current generated by the receiving wireless coil is connected to the isolation transformer at the discrete coil connection.

18. The apparatus of claim 12, wherein wired power transmission is associated with a common-mode connection at the wireless coil, and wireless power transmission is associated with a differential-mode connection at the wireless coil.

19. The apparatus of claim 18, wherein the wireless coil has a detachable coil connection.

20. The apparatus of claim 19, wherein a conductor indicating the current and / or voltage generated by the secondary side of the electrical isolation transformer is connected to the wireless coil at a separate coil connection.

21. A method for charging an energy storage device, the energy storage device comprising an on-board charger circuit and a wireless charger circuit, the on-board charger circuit and the wireless charger circuit sharing a rectifier stage; the method comprising: At least one of a common-mode conduction path and a differential-mode conduction path is used for on-board charging, and the other of the at least one of the common-mode conduction path and the differential-mode conduction path is used for wireless charging.

22. The method of claim 21, wherein the common-mode conduction path and the differential-mode conduction path are dynamically allocated based on the detected electrical characteristics of the energy storage device during charging.

23. The method of claim 22, wherein the detected electrical characteristics are based at least on the charging efficiency of the energy storage device being greater than or less than a predefined efficiency threshold.

24. The method of claim 21, wherein the common-mode conduction path is used for wireless charging.

25. The method of claim 21, wherein the differential mode conduction path is used for wireless charging.

26. The method of claim 21, wherein during operation of the on-board charger circuit, no magnetic field is generated on the coil of the wireless charger circuit, and the circulating current on the wireless charger circuit is minimized.

27. The method of claim 21, wherein during operation of the wireless charger circuit, the electrical loss on the vehicle charger circuit does not increase.

28. The method of claim 24, wherein the output current of the wireless charger is divided into two or more parallel paths leading to the load, wherein one or more parallel paths are used for the common-mode conduction path.

29. The method of claim 21, wherein for the common-mode conduction path, the currents leaving the winding terminals of the transformer are in phase, and for the differential-mode conduction path, the currents leaving the winding terminals of the transformer are out of phase.

30. A non-transitory machine-readable medium storing instructions that, when executed by a processor, cause the processor to perform a method for charging an energy storage device according to any one of claims 21 to 29.

31. A transmission system comprising the means according to any one of claims 1 to 20.

32. A vehicle comprising the transmission system according to claim 31.

33. The vehicle according to claim 32, wherein the vehicle is any one of an automobile, a ship, an airplane, or an autonomous aircraft.

34. A portable energy storage device comprising the means according to any one of claims 1 to 20.

35. The portable energy storage device according to claim 34, wherein the portable energy storage device is any one of a portable battery pack or a portable electronic device.

Images