Inductive charging device and inductive power transfer system

Abstract

The invention relates to an inductive charging device, in particular for a vehicle charging system, comprising a first energy coil, a positioning device, and a compensation device with at least one primary-side compensation coil and a secondary-side compensation coil inductively coupled thereto. The at least one primary-side compensation coil is electrically connected to the at least one transmitting coil and, during positioning operation, carries the same or a proportional current as the transmitting coil, inducing a compensation voltage in the secondary-side compensation coil. This voltage is inverted relative to any disturbance voltage induced by the at least one transmitting coil into the first energy coil and results in a compensation current that is fed into the energy coil.

Description

[0001] The invention relates to an inductive charging device, in particular for a vehicle charging system, and a system for inductive energy transfer.

[0002] An inductive power transfer system typically comprises a stationary inductive charging unit (hereinafter also referred to as "inductive charging unit" or "inductive charging device") and a mobile inductive charging unit. During charging, an energy coil (hereinafter also referred to as the "first energy coil") of one of the inductive charging units acts as a primary coil, and the energy coil (hereinafter also referred to as the "second energy coil") of the other inductive charging unit acts as a secondary coil. Hereinafter, the "energy coils" are also referred to as "power coils," "transfer coils," or "power transfer coils."

[0003] Such systems are typically used for inductive power transfer to a mobile application, such as a motor vehicle, where the mobile application includes the mobile inductive charging device. In these mobile applications, the primary coil of the mobile inductive charging device is usually the secondary coil during charging operation. For inductive power transfer, the primary coil generates an alternating magnetic field, which induces a voltage in the secondary coil. To enable inductive power transfer and increase its efficiency, the primary and secondary coils, and thus the power coils of the inductive charging devices, must be positioned relative to each other accordingly.

[0004] From DE 102022203489 A1, a system for inductive energy transfer, particularly to a mobile application, is known, comprising a stationary inductive charging device with a stationary energy coil and a mobile inductive charging device with a mobile energy coil. Precise and robust detection of the relative position of the energy coils is achieved with a positioning device, which has four transmitting coils in one of the inductive charging devices and at least one receiver in the other. The transmitting coils generate distinguishable positioning fields, which interact with the at least one receiver, whereby the ratio of the positioning fields is used to detect whether the energy coils overlap.

[0005] From DE 102022120691 A1, an inductive charging device for a vehicle charging system is known, comprising an energy transfer winding, at least one flux guide element, and at least one positioning signal winding. The positioning signal winding is designed as a solenoid with a winding axis oriented in the longitudinal direction of the vehicle or the intended longitudinal direction of the vehicle. The flux guide element is suitable for guiding a magnetic field during an energy transfer process that takes place between another inductive charging device and the energy transfer winding. The positioning signal winding surrounds at least one of the at least one flux guide elements and the energy transfer winding.

[0006] From DE 102022107568 A1, an inductive charging device for a vehicle charging system is known, comprising an energy transfer winding, at least one flux guide element, and at least one first sensor winding and a second sensor winding. The flux guide element is designed to guide a magnetic field during energy transfer between another inductive charging device and the energy transfer winding. The first and second sensor windings are arranged around at least one of the at least one flux guide element. A voltage is induced in the sensor windings by the magnetic field of a positioning signal winding. This voltage is proportional to the component of the magnetic field that is perpendicular to the respective radial longitudinal direction of the sensor winding. The position of the vehicle relative to the inductive charging device can be determined using these voltages.

[0007] The present invention is based on the objective of improving the accuracy of positioning.

[0008] According to one aspect of the present invention, an inductive charging device is provided with: - a first energy coil for generating an alternating magnetic field for inductive energy transfer to a second energy coil of a second inductive charging device in an energy transfer operation; - a positioning device with at least one transmitting coil for generating a positioning magnetic field for detecting the relative positioning of the energy coils to each other in a positioning operation; and - a compensation device with at least one primary-side compensation coil and a secondary-side compensation coil inductively coupled thereto, wherein the at least one primary-side compensation coil is electrically connected to the at least one transmitting coil and, in positioning operation, is traversed by the same or a proportional current as the transmitting coil and induces a compensation voltage in the secondary-side compensation coil, which is inverted with respect to a disturbance voltage induced by the at least one transmitting coil into the first energy coil and leads to a compensation current that is fed into the energy coil.

[0009] According to a further aspect of the present invention, an inductive power transfer system is provided with an inductive charging device according to the present invention, in particular a stationary inductive charging device for mounting on and / or in a ground surface (hereinafter also referred to as "Ground Assembly" (GA)), and with a further inductive charging device, in particular a mobile inductive charging device for mounting on and / or in a vehicle (hereinafter also referred to as "Vehicle Assembly" (VA)), wherein the further inductive charging device comprises: - a second energy coil for receiving energy inductively transferred from the first energy coil during energy transmission operation; and - a positioning device with at least one receiving coil for detecting the positioning magnetic field and for recognizing the relative positioning of the energy coils to each other during positioning operation.

[0010] Preferred embodiments of the invention are defined in the dependent claims. It is understood that the claimed inductive energy transfer system has similar and / or identical preferred embodiments to the claimed inductive charging device, in particular as defined in the dependent claims and as disclosed herein.

[0011] The inventors recognized that integrating one or more transmitting coils of the positioning device (hereinafter also referred to as the "Differential Inductive Positioning System" (DIPS)) into the inductive charging device to generate positioning magnetic fields creates mutual inductance between these transmitting coils and the respective power coil of the inductive charging device. This magnetic coupling induces a voltage in the power coil during operation of the transmitting coils. Due to the design of the compensation circuit unit, which generally includes inductive and / or capacitive components and can form a resonant circuit, a current also flows there, and a current flow may occur even without compensation. This current, in turn, builds up a magnetic field that influences the original field of the transmitting coils through superposition.

[0012] The described effect occurs particularly in stationary inductive charging devices, where the transmitting coils are preferably located. A comparable effect can also occur in mobile inductive charging devices due to the design of the compensation circuit unit generally used there. There, too, a resonant circuit can develop, which can lead to a current flow in the power coil if, for example, a passive rectifier is directly connected to the coil and the induced voltage by the positioning coils exceeds the threshold voltage of the rectifier diodes. Receiver coils of the positioning device for detecting a positioning magnetic field of the mobile inductive charging device thus possess a mutual inductance of the corresponding power coil.In connection with the present invention, the term "vehicle" shall be understood generally as any mobile application and thus include not only motor vehicles, but also, for example, industrial trucks, robots, forklifts, etc.

[0013] Furthermore, the coils of the stationary inductive charging device and the coils of the mobile inductive charging device form a mutual inductance, and vice versa. This ultimately creates a matrix of mutual inductances among all the coils.

[0014] The compensation device according to the invention, comprising at least one primary-side compensation coil and an inductively coupled secondary-side compensation coil, allows the currents in the power coil induced by the positioning magnetic field—i.e., the interference currents induced by the at least one transmitting coil—to be attenuated or even eliminated by injecting an inverted induced voltage into the power coil (in particular, into the GA power coil). For this purpose, the at least one primary-side compensation coil is electrically connected to the at least one transmitting coil so that, during positioning operation, it carries the same or a proportional current as the respective transmitting coil.This induces a compensation voltage in the secondary-side compensation coil. This voltage is inverted relative to any (undesired) interference voltage induced into the first power coil by the at least one transmitting coil, resulting in a compensation current that is fed into the first power coil. This compensates for the interference voltage, leading to an improvement in the accuracy of the position determination.

[0015] In a preferred embodiment, the positioning device comprises at least two transmitting coils, each configured to generate different positioning magnetic fields, and the compensation device comprises at least two primary-side compensation coils, each connected to a transmitting coil and carrying the same or a proportional current as the respective transmitting coil during positioning operation. Generally, more than one transmitting coil is provided, generating different positioning magnetic fields, particularly in the case of alternating magnetic fields with different frequencies, to improve positioning accuracy. Preferably, a primary-side compensation coil is provided for each coil, generating a compensation current in the secondary-side compensation coil. This current compensates for the interference voltage induced by the respective transmitting coil in the first power coil.is adapted to the corresponding interference current in the first energy coil.

[0016] In a further preferred embodiment, the compensation device comprises a plurality of primary-side compensation coils and a plurality of secondary-side compensation coils, each corresponding to a plurality of transmitting coils of the positioning device. During positioning operation, the primary-side compensation coils are each traversed by the same or a proportional current as a respective transmitting coil. Thus, for each transmitting coil, one primary-side compensation coil and one secondary-side compensation coil are provided, each generating a compensation current (or compensation current component) that then flows through the first energy coil. For example, if there are five transmitting coils, five compensation current components are generated, which—together as a compensation current—flow through the first energy coil, thereby achieving improved compensation.Preferably, the secondary-side compensation coils are electrically connected in series.

[0017] In a further preferred embodiment, the at least one secondary-side compensation coil is electrically connected to the first energy coil, particularly in series, or is arranged at another location within the inductive charging device to feed the compensation current into the first energy coil. In principle, the type and position of the electrical connection are less relevant, provided that a compensation current is generated and fed into the first energy coil. For example, the at least one secondary-side compensation coil can be connected in series with an inverter or in series with a parallel capacitor.

[0018] Various embodiments are possible for the specific design and arrangement of the compensation device. In one embodiment, the at least one primary-side compensation coil and at least one secondary-side compensation coil are arranged on a common core, with preferably all primary-side compensation coils and all secondary-side compensation coils being arranged on a common core. The compensation device is ultimately designed in the form of a transformer. The advantage of this solution is that the number of cores can be reduced, which in turn lowers hardware and assembly costs.

[0019] In an alternative embodiment, the at least two primary-side compensation coils are arranged on a first leg of a core, and the at least one secondary-side compensation coil is arranged on a second leg of the core. Alternatively, the one primary-side compensation coil and one secondary-side compensation coil can each be arranged on different legs of a shared core. Thus, a separate core can be provided for each pair of primary-side and secondary-side compensation coils. This solution has the advantage that each individual transmitting coil can be compensated more precisely, and the coupling of multiple transmitting coils by a common core can be avoided.

[0020] The first energy coil can have two (or more) sub-coils connected in parallel, with the secondary-side compensation coil being electrically connected to the parallel connection of the two (or more) sub-coils. For example, the first energy coil can have two (or more) parallel energy coil windings.

[0021] If the first energy coil has two (or more) sub-coils, it may be provided that a separate compensation device is used for each sub-coil. Alternatively, a common compensation device may be used.

[0022] In one implementation, the positioning device has five transmitting coils, which are designed to generate different positioning magnetic fields and are arranged at different positions. A comparable positioning device, which can also be used in the present case, is known, for example, from the aforementioned DE 102022203489 A1, which has four transmitting coils. A positioning device with a fifth transmitting coil (also referred to there as a positioning signal winding) is known from the aforementioned DE 102022120691 A1.

[0023] Preferably, the five transmitting coils are each configured to generate an alternating magnetic field with a different frequency, wherein the main magnetic field directions of the alternating magnetic fields of four transmitting coils are essentially parallel, and the main magnetic field direction of the alternating magnetic field of the fifth transmitting coil is essentially perpendicular to the main magnetic field directions of the alternating magnetic fields of the other four transmitting coils. This allows for good positioning results.

[0024] Such an inductive charging device is preferably used as a stationary inductive charging device for mounting on and / or in a floor surface. In principle, the inductive charging device according to the invention can also be designed as a mobile inductive charging device for mounting on and / or in a vehicle.

[0025] For reactive power compensation, a compensation circuit unit is preferably used, in particular with a series capacitor connected in series with the power coil and / or a parallel capacitor connected in parallel with the power coil. Such a compensation circuit unit is generally known, and various configurations are conceivable. In one configuration, the compensation circuit unit has a parallel capacitor and one or two series capacitors. In another configuration, the compensation circuit unit has one or two series inductors arranged between an input terminal and an output terminal. The specific design of the compensation circuit unit depends, among other things, on the desired behavior of the power transmission system, i.e., whether, for example, a constant voltage is to be provided by the power transmission system.Depending on the design of the compensation, different behaviors can be achieved. Furthermore, the design can also depend on how many degrees of freedom are available or required. In a preferred embodiment, LCC compensation is used.

[0026] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the present invention. Exemplary embodiments of the invention are illustrated in the following drawings and are explained in more detail in the following description, where identical reference numerals refer to identical, similar, or functionally equivalent components. The drawings show: Fig. 1 a highly simplified representation of a vehicle with an inductive charging device; Fig. 2 a sectional view of an inductive charging device for a vehicle charging system; Fig. 3 a top view of an inductive charging device according to the invention with a near positioning transmitter and a far positioning transmitter; Fig. 4 a top view of an alternative inductive charging device according to the invention with a near positioning transmitter and a far positioning transmitter; Fig. 5 a flat coil as a near positioning transmitter for a near positioning transmitter device; Fig. 6 an inductive charging device with a positioning receiving device for a vehicle charging system according to the invention; Fig. 7 an inductive charging device with a positioning receiving device for a vehicle charging system according to the invention; Fig. 8 a vehicle during a positioning process with a vehicle charging system according to the invention; Fig. 9 a known circuit device for reactive power compensation in a stationary inductive charging device; Fig. 10 a known circuit device for reactive power compensation in a mobile inductive charging device; Fig. 11 a schematic representation of another embodiment of the inductive charging device; Fig. 12 a schematic representation of another embodiment of the inductive charging device; Fig. 13 a schematic representation of an embodiment of a compensation device used according to the invention; Fig. 14 a schematic representation of a first embodiment of the inductive charging device according to the invention; Fig. 15 a schematic representation of a second embodiment of the inductive charging device according to the invention; Fig. 16 a schematic representation of a third embodiment of the inductive charging device according to the invention; Fig. 17 a schematic representation of a fourth embodiment of the inductive charging device according to the invention; Fig. 18 a schematic representation of a fifth embodiment of the inductive charging device according to the invention; Fig. 19 a schematic representation of a sixth embodiment of the inductive charging device according to the invention; and Fig. 20 a schematic representation of a seventh embodiment of the inductive charging device according to the invention.

[0027] Fig. Figure 1 shows a mobile inductive charging device 1a, which is arranged on a vehicle 2 with an energy storage device 3 and is positioned above a stationary inductive charging device 1b. During operation, energy can be transferred from the stationary inductive charging device 1b to the mobile inductive charging device 1a, thereby charging the energy storage device of the vehicle 3.

[0028] The mobile inductive charging device 1a and the stationary inductive charging device 1b together form, or are part of, a vehicle charging system 8. In principle, it is also possible to operate the vehicle charging system 8 bidirectionally. In this case, energy can be temporarily transferred from the mobile inductive charging device 1a to the stationary inductive charging device 1b. The in Fig. 1. A stationary inductive charging device 1b arranged on the surface 35 can alternatively also be recessed into the roadway (not shown here). In a recessed arrangement, the inductive charging device 1b can be covered by certain layers of the roadway or be flush with the roadway surface.

[0029] Fig. Figure 2 shows a side section through an inductive charging device 1, 1a, which includes several flux guide elements 5 and an energy transfer winding 4 (energy coil) and is mounted on a vehicle 2. A corresponding arrangement exists for a stationary inductive charging device 1b, except that this is arranged on a surface instead of on a vehicle 2 (not shown).

[0030] Fig. Figure 3 shows a top view of an inductive charging device according to the invention, in which the circuit device according to the invention can be used, with a near-positioning transmitter NAH-POS and a far-positioning transmitter FERN-POS. The near-positioning transmitter NAH-POS is implemented here in the form of four near-positioning windings 13 (transmitting coils), but can also be implemented with more or fewer transmitting windings. The far-positioning transmitter FERN-POS is implemented here as a solenoid (positioning signal winding). During a positioning process, the far-positioning transmitter FERN-POS emits a far-positioning signal FERN-SIG in the form of an alternating magnetic field. During a positioning process, the near-positioning transmitter NAH-POS emits several near-positioning signals NAH-SIG in the form of alternating magnetic fields, which differ, for example, in frequency.

[0031] Fig. Figure 4 shows a top view of an alternative inductive charging device according to the invention, in which the circuit device according to the invention can be used, with a near-positioning transmitter NAH-POS and a far-positioning transmitter FERN-POS. Here too, the near-positioning transmitter NAH-POS is implemented as four near-transmitting windings 13 and the far-positioning transmitter FERN-POS as a solenoid. This embodiment shows an alternative arrangement of the flux guide elements 5. Furthermore, the far-positioning signal winding 41 (positioning signal coil) does not run centrally through the center of the inductive charging device 1, but is shifted towards an edge.

[0032] Fig. Figure 5 shows a near-transmitting winding 13, which is designed as a flat coil.

[0033] Fig. Figure 6 shows another inductive charging device 1, which includes a positioning receiver with two sensor windings 9a and 9b (receiving coils) that are part of a sensor assembly. This can be a mobile inductive charging device 1a or a stationary inductive charging device 1b. In the present embodiment, eight flux guide elements 5 are shown, arranged radially around the center 7 of the energy transfer winding 4 in the plane. However, there can also be more or fewer flux guide elements. Narrow gaps 27 are located between the flux guide elements 5. The gaps also extend radially around the center 7, thus the gaps run approximately in the main direction of the magnetic field lines (here three magnetic field lines 14 are symbolically indicated) that are established in the flux guide elements 5 during energy transfer.The energy transfer winding 4, which is concealed in the top view by the flux guide elements 5, is indicated by a dashed line. Here, the energy transfer winding 4 is a flat coil. The sensor windings are designed as solenoids, also called cylindrical coils.

[0034] The first sensor winding 9a is wound around two flux guide elements 5, which are diagonally opposite each other with respect to the center 7 of the energy transfer coil 4. The second sensor winding 9b is similarly wound around two further flux guide elements 5, which are also diagonally opposite each other with respect to the center 7. The first sensor winding 9a is arranged axially symmetrically to the second sensor winding 9b with respect to the vehicle's longitudinal direction 6. The first sensor winding 9a and the second sensor winding 9b intersect at least approximately at the center 7 of the energy transfer coil 4. The first sensor winding 9a has a first radial longitudinal direction 11a, and the second sensor winding 9b has a second radial longitudinal direction 11b. The angle 15 between the first radial longitudinal direction 11a and the vehicle's longitudinal direction 6 is at least approximately equal to the angle 16 between the second radial longitudinal direction 11b and the vehicle's longitudinal direction 6.

[0035] During the charging process, the vehicle 2 is positioned above the stationary inductive charging device 1b, and energy is transferred to the inductive charging device 1a. The flux guide elements 5 perform the flux guide function. In the charging state, the magnetic field lines run approximately radially within them. Since the first radial longitudinal direction 11a and the second radial longitudinal direction 11b are also radially aligned and thus at least approximately parallel to the magnetic field lines, relatively little to no voltage is induced in the first sensor winding 9a and the second sensor winding 9b. This is advantageous because, with the high power levels of energy transfer and thus high flux densities, the sensor windings could otherwise easily be destroyed. Therefore, no additional effort is required to prevent damage to the arrangement.

[0036] Fig. Figure 7 shows a top view of another embodiment of an inductive charging device 1 according to the invention, in which the circuit arrangement according to the invention can be used. Here, four sensor windings 9a, 9b, 9c, 9d with four radial longitudinal directions 11a, 11b, 11c, 11d are present. However, there can also be more or fewer sensor windings. Each sensor winding is arranged around a different flux guide element 5. Two of the flux guide elements are diagonally opposite each other with respect to the center 7 of the energy transfer coil 4. Together, the four sensor windings 9a, 9b, 9c, 9d again form a cross-shaped arrangement. An advantage over the arrangement shown in Figure 7 is that... Fig. 6 is that the area around the center 7 of the energy transfer coil 4 is designed without a sensor winding 9. This allows mechanically necessary support elements (not shown) to still be arranged here.

[0037] The inductive charging device according to the invention Fig. 3 and Fig. 4 and the further inductive charging device according to Fig. 6 and Fig. 7 can be part of a vehicle charging system 8 according to the invention. In this system, one positioning receiver can receive signals from both the near-positioning transmitter (NAH-POS) and the far-positioning transmitter (FERN-POS). This is advantageous because one positioning receiver can operate two different positioning methods that function optimally at two different distance ranges.

[0038] Fig. Figure 8 a) shows a vehicle 2 with a longitudinal direction 6 and a mobile inductive charging device 1a during a positioning process over a stationary inductive charging device 1b with a target longitudinal direction 6a. The vehicle 2 moves directly towards the stationary inductive charging device 1b, and the target longitudinal direction 6a is therefore equal to the longitudinal direction 6. In the mobile inductive charging device 1a, in addition to the energy transfer winding (not shown), there is a remote positioning signal winding 41 and four near-transmit windings 13. The remote positioning signal winding 41 has a winding axis 36 and a radial longitudinal direction 11. The four near-transmit windings 13 have winding axes perpendicular to the surface. The stationary inductive charging device 1b has, in addition to the energy transfer winding (not shown), two sensor windings 9a and 9b.Both sensor windings 9a and 9b each have a radial longitudinal direction 11a and 11b. Both sensor windings 9a and 9b are arranged symmetrically to the intended vehicle longitudinal direction 6a. This arrangement of the windings for positioning is particularly advantageous. The remote positioning signal winding 41 generates a relatively homogeneous magnetic field. A voltage is induced in the sensor windings 9a and 9b by the magnetic field of the remote positioning signal winding 41. If the vehicle approaches the stationary inductive charging device 1b at a precise perpendicular angle, as shown in the left-hand diagram, an equal voltage is induced in both sensor windings 9a and 9b during the remote positioning procedure FERN_V. From a certain distance, the near positioning procedure NAH_V is used, and the near positioning signals NAH-SIG emitted by the near transmitting windings 13 are evaluated.

[0039] Fig. Figure 8 b) shows an embodiment in which the remote positioning signal winding 41 and the four local transmit windings 13 are arranged in the stationary inductive charging device 1b, and the sensor windings 9a and 9b are arranged in the mobile inductive charging device 1a. The operation of this embodiment is otherwise the same as described above with regard to Fig. 8 a) described functionality. Shown here is a case in which the vehicle 2 does not approach the stationary inductive charging device 1b perpendicularly, but deviates from it at an angle of approximately 45°. The vehicle's longitudinal direction 6 and the connecting line between the stationary inductive charging device 1b and the mobile inductive charging device 1a are thus at a directional deviation angle of 45° to each other. In this case, the remote positioning signal winding 41 generates a magnetic field that is perpendicular to the first sensor winding 9a. Here, a maximum voltage is induced in the first sensor winding 9a during the remote positioning procedure FERN_V. The magnetic field generated by the remote positioning signal winding 41 is also approximately parallel to the second sensor winding 9b. Here, a minimal or no voltage is induced during the remote positioning procedure FERN_V.Here too, the close positioning method NAH_V can take over from a certain distance.

[0040] With the in the Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7 to Fig. In the differential inductive positioning system (DIPS) described in section 8 for an inductive charging system, a specific positioning magnetic field is generated by arranging several transmitting coils on the stationary inductive charging device (also referred to as the ground assembly (GA)) to ensure interoperability between the GA and the mobile inductive charging device (also referred to as the vehicle assembly (VA)) from different manufacturers. Due to the coupling between the transmitting coils and the one or more GA power coils (i.e., the one or more energy coils of the stationary inductive charging device), the induced voltage in the GA power coils, driven by the transmitting coils, may induce a current in the GA power coils.The magnetic field generated by this current superimposes itself on the positioning magnetic field, thereby influencing the distribution of the positioning magnetic field and thus the evaluation of the positioning field in the VA. The same problem exists between the transmitting coils and the one or more VA power coils (i.e., the one or more energy coils of the mobile inductive charging device). Here, currents can also be induced in the VA power coil, which in turn influence the positioning magnetic field.

[0041] The state of the art for inductive charging systems includes the applicable standards SAE J2954, ISO 19363, and IEC 61908. These are harmonized and provide reference designs (mechanical description of a coil design and electrical description of the transmission path) as a guide for product development and testing. A circuit device for reactive power compensation in the GA according to SAE J2954 with parallel compensation is described in Fig. Figure 9 shows a circuit device for reactive power compensation in the VA according to SAE J2954 with parallel compensation. Fig. 10 shown.

[0042] The in Fig. 9 and Fig. The 10 circuit configurations shown exemplify a compensation circuit unit with a capacitor C2 connected in parallel to the respective transmission coil LGA (for the GA) or LVA (for the VA), as well as two capacitors C1a and C1b connected in series with it. Although it can be assumed that such parallel compensation is most commonly used for reactive power compensation, other circuit configurations are also conceivable.

[0043] Fig. Figure 11 shows a schematic simplified representation of another embodiment of the inductive charging device 1b, which, in addition to the energy coil 4, has both a positioning signal winding 41 and four transmitting coils 13. The positioning signal winding 41 is arranged as a solenoid in the central area around the energy coil 4 and the flux guide elements 5. The four transmitting coils 13 are arranged in the four corners above or below the energy coil 4. Further details of the Fig. 3, Fig. 4 and Fig. The inductive charging device 1b shown in 11 is disclosed in DE 102022203489 A1 and DE 102022120691 A1, to which explicit reference is hereby made and whose disclosure is hereby incorporated into the present application by this reference.

[0044] Fig. Figure 12 shows a schematic representation of another embodiment of the inductive charging device 1a, which, in addition to the energy coil 4, has two sensor windings 9a, 9b. Further details of the embodiment are shown in the Fig. 6, Fig. 7 and Fig. The inductive charging device 1a shown in 12 is disclosed in DE 102022107568 A1, to which explicit reference is hereby made and whose disclosure is hereby incorporated into the present application by this reference.

[0045] Through the integration of the DIPS, i.e., in particular the positioning device of the GA with the transmitting coils and / or the positioning signal coil (see e.g. Fig. 3, Fig. 4 and Fig. 11) In the existing circuit arrangement for energy transfer, a mutual inductance is created between the coils of the DIPS, i.e., the near-transmitting windings 13 (transmitting coils) and / or the far-positioning signal winding 41, and the energy transfer winding 4 (energy coil). This magnetic coupling induces a voltage in the energy coil 4 during operation of the DIPS coils 13, 41, which leads to a current flow. This current, in turn, builds up a magnetic field that influences the original field of the DIPS coils through superposition.

[0046] The same effect is produced by the resonant circuit with the parallel capacitance C2 in Fig. Circuit arrangement shown in 10 for the VA. Each of the two sensor windings 9a, 9b (see e.g. Fig. 6, Fig. 7 and Fig. 12), which are part of the VA's positioning device, have a mutual inductance with the VA's power coil. Simultaneously, all coils of the GA also form a mutual inductance with all coils of the VA, and vice versa. This creates a matrix of mutual inductances among all coils.

[0047] According to the invention, currents induced in the first energy coil (in the GA) by one or more transmitting coils, which are excited by the positioning magnetic field of the respective transmitting coil, are dampened or completely eliminated by feeding an inverted induced voltage into the first energy coil 4.

[0048] Fig. Figure 13 shows a schematic representation of an embodiment of a compensation device 100 used according to the invention, comprising at least one primary-side compensation coil 110 and a secondary-side compensation coil 120 inductively coupled thereto. The compensation device 100 serves as a feed-in circuit for the counter-voltage (compensation voltage) into the first power coil. In principle, such a compensation device 100 can be provided for each transmitting coil.

[0049] In the case of n transmitting coils, for example, n primary-side compensation coils 110 are provided. The m (1 ≤ m ≤ n) secondary-side compensation coils 120 are preferably coupled to each other via a common magnetic core using a coupling factor M. It should be noted that even if there is only one power coil, it is possible to connect secondary-side compensation coils in series at several points in the circuit of the stationary charging device. Therefore, m does not need to be limited and can theoretically assume any value. The n primary-side compensation coils 110 are feed-in coils whose currents are given by i 1,1 until i 1,n They can be designated as such. They can be used to feed induced voltages of different frequencies into the m secondary-side compensation coils 120. The m secondary-side compensation coils 120 can be connected in series with one of m energy coils, whose currents are denoted by i. 2,1 until i 2,mThe number of secondary-side compensation coils is fundamentally independent of the number of energy coils. The secondary-side compensation coils are not necessarily connected in series with the energy coils. The induced voltage fed into the energy coil circuit can be adjusted by setting the coupling factor and the currents i. 1,1 until i 1,n The coil must be adjusted so that the voltage excited by the transmitting coil in the power coil completely cancels out the induced voltage in the power coil and thus the induced current in the power coil. 1,1 to L 1,n represent the self-inductance of the primary compensation coil. L 2,1 to L 2,m represent the self-inductance of the secondary-side compensation coil.

[0050] Fig. Figure 14 shows a schematic representation of a first embodiment of the inductive charging device 200 according to the invention for a vehicle charging system, in particular a stationary inductive charging device 200 for mounting on and / or in a floor surface. The inductive charging device 200 comprises a first energy coil 210 for generating an alternating magnetic field for inductive energy transfer to a second energy coil (not shown) of a second inductive charging device (not shown) in an energy transfer mode, and a positioning device 220 with at least one transmitting coil 221 for generating a positioning magnetic field for detecting the relative positioning of the energy coils to each other in a positioning mode. Furthermore, a compensation device 100 is provided, for example in the form of the one shown in Figure 14. Fig. The compensation device 100 shown in Figure 13 comprises at least one primary-side compensation coil 110 and a secondary-side compensation coil 120 inductively coupled to it. It should be noted that the definition of the terminals with the points of the transformer depends on the definition of the positive direction of the current.

[0051] In the present embodiment, the primary-side compensation coil 110 is electrically connected to the transmitting coil 221, and the secondary-side compensation coil 120 is electrically connected to the power coil (GA power coil) 210. However, other coupling or electrical connection options are also possible. During positioning operation, the primary-side compensation coil 110 is thereby traversed by the same or a proportional current as the transmitting coil 221, thereby inducing a compensation voltage in the secondary-side compensation coil 120. This voltage is inverted relative to any disturbance voltage induced by the transmitting coil 221 into the power coil 210 and results in a compensation current that is fed into the power coil 210.

[0052] A first mutual inductance is thus formed between the transmitting coil 221 and the power coil 210. The second mutual inductance formed between the two compensation coils 110 and 120 serves to eliminate the induced current generated by the first mutual inductance. The second mutual inductance can be realized, for example, by winding the connecting wires of the transmitting coil 221 and the power coil 210 onto a single core. If the structure and the relative position of the transmitting coil 221 and the power coil 210 are fixed, the value of M2 is constant. By adjusting the air gap of the core on which the two compensation coils 110 and 120 are arranged, it can be ensured that M1 equals M2. This effectively eliminates the current induced by the transmitting coil 221 into the power coil 210.

[0053] Fig. Figure 15 shows a schematic representation of a second embodiment of the inductive charging device 200 according to the invention. In this case, the positioning device has, by way of example, five transmitting coils (not shown), for example, the four near-field transmitting windings 13 and the far-field positioning signal winding 41 shown above. The compensation device 100 has one primary-side compensation coil for each transmitting coil, thus five primary-side compensation coils 110-114, and one secondary-side compensation coil for each transmitting coil, thus five secondary-side compensation coils 120-124. The five primary-side compensation coils 110-114 are each energized by the current of the corresponding transmitting coil. The five secondary-side compensation coils 120-124 are electrically connected in series with each other and with the power coil 210.A central control unit 230 (also referred to as a GA circuit) controls the energy coil 210 and determines whether the charging device is in positioning mode, in which the energy coil 210 is preferably inactive, or in energy transfer mode, in which the energy coil 210 transfers energy and the positioning device is preferably inactive. Through the additional mutual inductances of the secondary compensation coils 120-124, mutual induction voltages are thus introduced into the circuit of the energy coil 210 in order to minimize or completely eliminate the current in the energy coil 210 during positioning operation.

[0054] Fig. Figure 16 shows a schematic representation of a third embodiment of the inductive charging device 200 according to the invention. The secondary compensation coils 120-124 can, for example, be electrically connected in series with the energy coil 210. However, they can also be connected to the control unit 230 at another location, provided that it is ensured that the induced currents are supplied to the energy coil.

[0055] Fig. Figure 17 shows a schematic representation of a fourth embodiment of the inductive charging device 200 according to the invention. In this embodiment, the energy coil is divided into two partial coils 211, 212 (there can also be more), for example, consisting of two parallel windings. In this case, too, it is possible to use only one set of mutual inductances, i.e., to design the compensation device 100 as described, for example, in Fig. 15 or Fig. Figure 16 shows how to reduce or eliminate the induced current in the sub-coils 211, 212 of the energy coil. Also in the Fig. In the embodiment shown in 16, two or more partial coils can be provided, which are connected in parallel or separately to the control unit 230.

[0056] Fig. Figure 18 shows a schematic representation of a fifth embodiment of the inductive charging device 200 according to the invention. In this embodiment, the energy coil is also divided into two sub-coils 211, 212 (there can also be more). In this embodiment, a compensation device 101, 102 is used for each sub-coil, each like the one in Fig. 15 and Fig. The compensation device 100 shown in Figure 16 can be designed to reduce or eliminate the induced current in the sub-coils 211, 212 of the energy coil.

[0057] Fig. Figure 19 shows a schematic representation of a sixth embodiment of the inductive charging device 200 according to the invention. In this embodiment, the compensation device 100 has several cores, i.e., each pair of primary-side and secondary-side compensation coils is wound on its own core, preferably on different legs of the core. For example, the primary-side compensation coil 110 is arranged on a first leg 131 of a first core 130, and the associated secondary-side compensation coil 120 is arranged on a second leg 132 of the first core 130.

[0058] Fig.Figure 20 shows a schematic representation of a seventh embodiment of the inductive charging device 200 according to the invention. In this embodiment, the compensation device 100 physically has a single core, i.e., the primary-side and secondary-side compensation coils are arranged on the core 130, preferably on different legs 131, 132. Furthermore, in this embodiment, only a single secondary-side compensation coil 120 is provided.

[0059] It goes without saying that further variations and combinations are possible. In particular, the number, design, and arrangement of the individual components shown in the embodiments are only examples and can be varied. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 102022203489 A1 [0004, 0022, 0043] DE 102022120691 A1 [0005, 0022, 0043] DE 102022107568 A1 [0006, 0044]

Claims

[1] Inductive charging device with: - a first energy coil for generating an alternating magnetic field for inductive energy transfer to a second energy coil of a second inductive charging device in an energy transfer operation; - a positioning device with at least one transmitting coil for generating a positioning magnetic field for detecting the relative positioning of the energy coils to each other in a positioning operation; and - a compensation device with at least one primary-side compensation coil and a secondary-side compensation coil inductively coupled thereto, wherein the at least one primary-side compensation coil is electrically connected to the at least one transmitting coil and, in positioning mode, is traversed by the same or a proportional current as the transmitting coil and induces a compensation voltage in the secondary-side compensation coil which is inverted with respect to a disturbance voltage induced by the at least one transmitting coil into the first energy coil and leads to a compensation current which is fed into the energy coil. [2] Inductive charging device according to claim 1, characterized by , that - the positioning device has at least two transmitting coils, each designed to generate different positioning magnetic fields, and - the compensation device has at least two primary-side compensation coils, each connected to a transmitting coil and which, in positioning operation, are traversed by the same or a proportional current as the respective transmitting coil. [3] Inductive charging device according to one of the preceding claims, characterized by , that - the positioning device has a plurality of transmitting coils, each designed to generate different positioning magnetic fields; and - the compensation device comprises a plurality of primary-side compensation coils and a plurality of secondary-side compensation coils, each corresponding to the plurality of transmitting coils of the positioning device, wherein the primary-side compensation coils in positioning operation are each traversed by the same or a proportional current as a respective transmitting coil. [4] Inductive charging device according to claim 3, characterized by that the secondary-side compensation coils are electrically connected in series. [5] Inductive charging device according to one of the preceding claims, characterized by that the at least one secondary-side compensation coil is electrically connected to the first energy coil, in particular in series, or is arranged at another location of the inductive charging device for feeding the compensation current into the first energy coil. [6] Inductive charging device according to one of the preceding claims, characterized by , that the at least one primary-side compensation coil and at least one secondary-side compensation coil are arranged on a common core, or that all primary-side compensation coils and all secondary-side compensation coils are arranged on a common core. [7] Inductive charging device according to one of claims 2 to 4, characterized by, that the at least two primary-side compensation coils are arranged on a first leg of a core and the at least one secondary-side compensation coil is arranged on a second leg of the core. [8] Inductive charging device according to one of claims 3 or 4, characterized by , that the primary-side compensation coil and the secondary-side compensation coil are each arranged on different legs of a respective common core. [9] Inductive charging device according to any of the preceding claims, characterized by , that the first energy coil has at least two sub-coils connected in parallel, wherein the secondary-side compensation coil is electrically connected to at least one of the sub-coils, in particular to the parallel connection of the two sub-coils. [10] Inductive charging device according to one of the preceding claims, characterized bythat the first energy coil has at least two sub-coils and that a compensation device, in particular a separate compensation device for each sub-coil, is provided for at least one sub-coil. [11] Inductive charging device according to one of the preceding claims, characterized by that the positioning device has five transmitting coils designed to generate different positioning magnetic fields and arranged at different positions. [12] Inductive charging device according to claim 11, characterized by, that the five transmitting coils are each designed to generate alternating magnetic fields with different frequencies, wherein the main magnetic field directions of the alternating magnetic fields of four transmitting coils are essentially parallel and the main magnetic field direction of the alternating magnetic field of the fifth transmitting coil is essentially perpendicular to the main magnetic field directions of the alternating magnetic fields of the other four transmitting coils. [13] Inductive charging device according to one of the preceding claims, characterized by that the inductive charging device is a stationary inductive charging device for installation on and / or in a floor surface. [14] Inductive charging device according to one of the preceding claims, further comprising a compensation circuit unit for reactive power compensation, in particular comprising a series capacitor connected in series with the energy coil and / or a parallel capacitor connected in parallel with the energy coil. [15] System for inductive energy transfer with an inductive charging device according to one of the preceding claims, in particular a stationary inductive charging device for mounting on and / or in a floor surface, and with a further inductive charging device, in particular a mobile inductive charging device for mounting on and / or in a vehicle, wherein the further inductive charging device comprises: - a second energy coil for receiving energy inductively transferred from the first energy coil during energy transmission operation; and - a positioning device with at least one receiving coil for detecting the positioning magnetic field and for recognizing the relative positioning of the energy coils to each other during positioning operation.

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