Inductive charging device for a vehicle charging system

Abstract

The invention relates to an inductive charging device for a vehicle charging system, said inductive charging device comprising an energy transfer winding, at least two flux-guiding elements, and at least one first sensor winding and one second sensor winding. The flux-guiding elements are designed to guide a magnetic field during energy transfer which takes place between another inductive charging device and the energy transfer winding, and the first sensor winding and the second sensor winding are each arranged between at least two of the at least two flux-guiding elements.

Description

[0001] Inductive charging device for a vehicle charging system

[0002] The invention relates to an inductive charging device for a vehicle charging system according to the preamble of the independent patent claim.

[0003] DE 10 2014 202 747 A1 discloses a double-winding system used to determine a positional deviation between a primary coil and a secondary coil of an inductive charging system. The two windings of the double-winding system are offset from each other by a specific angle and wound around a common ferrite element. The magnetic field of the primary coil induces a voltage in the two windings. The two voltages are evaluated by an evaluation unit, and a positional deviation between the primary coil and the secondary coil is calculated from this. For this purpose, the double-winding system requires the installation of an additional component with its own ferrite element. Furthermore, it is not possible to position the double-winding system in such a way that no or only very low voltages are induced during the charging process.

[0004] The present invention is concerned with the object of providing improved or at least alternative embodiments for an inductive charging device of the type mentioned above, in particular those which reduce the complexity and increase the longevity of the components used.

[0005] Being able to charge vehicles inductively offers a number of advantages over conventional conductive charging. First and foremost, the increased convenience is worth mentioning, as it eliminates the need to handle sometimes very heavy charging cables and plugs. However, for inductive charging, it is important that the vehicle's inductive charging device is positioned as precisely as possible in relation to the stationary, for example, floor-mounted inductive charging device. This is difficult if the vehicle is positioned purely manually over the stationary inductive charging device, and the driver requires support from an assistance system that either provides them with information about a positional deviation between the mobile inductive charging device in the vehicle and the stationary inductive charging device, or from an automated positioning system that directly takes over the parking process automatically.A sensor system capable of detecting a corresponding positional deviation is required. It is advantageous if no initial calibration is required between the stationary inductive charging device and the mobile inductive charging device in the vehicle. Furthermore, the positioning system should have the greatest possible range. This means that the positioning system should be able to precisely determine a positional deviation even at the greatest possible distance between a stationary inductive charging device and a mobile inductive charging device in the vehicle.

[0006] The device according to the invention with the features of the independent patent claim has the advantage over the prior art that sensor windings are integrated into the inductive charging device, no additional magnetic core or flux guide element is required, and the inventive arrangement of the sensor windings allows the voltages induced in the sensor windings during the charging process to be reduced to a minimum. Furthermore, the proposed arrangement also enables the sensor windings to be accommodated in the inductive charging device in the vehicle, which is usually delimited by a housing. No additional cabling is necessary, as would be the case with an arrangement outside the inductive charging device in the vehicle. In particular, the sensor windings are arranged according to the invention in such a way that no or only minimal additional installation space is required.Further important features and advantages of the invention emerge from the subclaims, from the drawings and from the associated description of the figures based on the drawings.

[0007] The present invention proposes an inductive charging device for a vehicle charging system, comprising an energy transmission winding and at least two flux guiding elements and at least one first sensor winding and one second sensor winding, having the following features: the flux guiding elements are suitable for guiding a magnetic field during an energy transmission which takes place between a further inductive charging device and the energy transmission winding, the first sensor winding and the second sensor winding are each arranged between at least two of the at least two flux guiding elements.

[0008] Inductive charging involves transferring energy in the form of a magnetic field between two inductive charging devices, usually between a stationary charging device and a mobile inductive charging device.

[0009] The term "inductive charging device" therefore refers here to only one of at least two components required for energy transfer during an inductive charging process. During the inductive charging process, an energy transfer winding in an inductive charging device generates an alternating magnetic field. This alternating magnetic field induces a voltage in another energy transfer winding of another inductive charging device. This additional inductive charging device thus serves as a counterpart for this specific charging process. The energy is transmitted wirelessly and absorbed by induction of a voltage. Inductive charging devices can be used for the inductive charging of vehicles. In principle, an inductive charging device according to the invention can be used for any type of land, water, or aircraft that has an electric or hybrid drive.

[0010] In particular, passenger cars, buses and trucks are mentioned here.

[0011] A vehicle charging system comprises at least one mobile inductive charging device and another, usually stationary, inductive charging device. A mobile inductive charging device can, for example, be mounted on and / or in a vehicle.

[0012] An inductive charging device on and / or in the vehicle is therefore suitable for absorbing the magnetic field and making electrical energy available from an energy storage device in the vehicle, for example a battery or accumulator in the vehicle.

[0013] In principle, a vehicle charging system can also be used for bidirectional charging. This allows the vehicle to temporarily feed energy from the energy storage system into the power grid via the vehicle charging system.

[0014] An inductive charging device has a power transmission coil that can efficiently receive and / or emit a magnetic field from another power transmission coil during the charging process. Preferably, power levels of 3 kW to 500 kW can be transmitted, particularly preferably 3 kW to 50 kW.

[0015] In general, a coil is defined here as a component for generating or receiving a magnetic field. A coil can consist of a winding and optionally other elements such as a magnetic core and a coil carrier. A winding is a wound arrangement of a current conductor. A winding can consist of one or more turns, with one turn representing one full circuit of a conductor. In general, however, a winding can also consist of fewer than one turn, for example, 0.5 turns. Of course, a partial number of turns, such as 2.5 turns, is also possible.

[0016] An energy transmission winding can be designed in various forms and can consist, for example, of a high-frequency stranded wire with a diameter between 0.5 mm and 10 mm, preferably made of copper.

[0017] The sensor windings are required for the positioning process. If the vehicle is still some distance away from the stationary inductive charging device, for example between 5 and 10 m, the stationary inductive charging device can emit a signal, preferably a magnetic field, which induces a voltage in the sensor windings. By comparing the voltages and correspondingly evaluating them, a positional deviation between the vehicle and the stationary inductive charging device can be determined. In principle, it is also possible for the mobile inductive charging device to emit the signal and the stationary inductive charging device to receive it. A sensor winding according to the invention can be designed in different forms and can have half, one, or preferably several turns. Of course, an incomplete number of turns, such as 2.5 turns, is also possible.A conductor of such a sensor winding can, for example, have a cross-sectional area between 0.01 and 2 mm. 2 A conductor can be implemented as a stranded wire, as a single conductor, or in another form, for example, in the form of a circuit board. In a conductor structure implemented on a circuit board, the conductor tracks can have cross-sections of, for example, the order of 0.8 mm by 35 pm.

[0018] A flux guide element is designed to guide a magnetic field in a predetermined manner. It has a high magnetic permeability with r >1 , preferably p r >50, especially preferred p r>100. The flux guide element represents a magnetic core for the energy transmission winding. In particular, the magnetic field is influenced by the high permeability in such a way that the greatest possible magnetic flux is transferred to the energy transmission winding. With a flux guide element, the energy transmission winding absorbs a greater magnetic flux than without a flux guide element, all other parameters being equal. A flux guide element can be made of a ferromagnetic or, preferably, a highly magnetic material, particularly preferably a ferrite. A flux guide element can preferably be plate-like—in the form of a planar core—and can be arranged in the inductive charging device on the side of the energy transmission winding facing away from the opposite side, i.e., the other inductive charging device.

[0019] In this case, one or more flux guiding elements can serve both as a flux guiding element for the energy transmission winding and as a flux guiding element for the sensor windings. A key feature of the invention is that the sensor windings do not have to be arranged directly around the corresponding flux guiding element(s). Since an energy transmission winding for inductively charging vehicles is relatively large, it also requires correspondingly large flux guiding elements. These often cannot be manufactured in one piece, or are very difficult to manufacture. Therefore, several smaller flux guiding elements are usually arranged side by side. A small gap then forms between these flux guiding elements.Furthermore, it can be advantageous to deliberately leave flux-guided element-free areas between flux-guided elements in order to save material, weight, and installation space, while still achieving a sufficiently positive influence on the magnetic field during energy transfer. The sensor windings can advantageously be arranged in these gaps or in these flux-guided element-free areas between flux-guided elements. The adjacent flux-guided elements have a sufficiently positive influence on the magnetic field of the sensor windings, and there is no need to wrap the flux-guided elements directly with the sensor windings. This is advantageous because, in particular, the installation space in the dimension perpendicular to the ground in inductive charging devices is very limited. This applies both to a stationary inductive charging device, which is arranged on the ground, for example, and should therefore be as flat as possible, and to a mobile inductive charging device.Arranging the sensor windings around flux guiding elements would increase the height of the inductive charging device in this dimension. However, if the sensor windings are arranged in gaps or other areas between flux guiding elements that are free of flux guiding elements, this does not increase the height of the inductive charging device. At the same time, the flux guiding elements laterally next to the sensor windings also act as flux guiding elements for the sensor windings and thus as flux guiding elements during the positioning process. The laterally arranged flux guiding elements also generate or influence a magnetic field of a sensor winding arranged in the gap or other area that is free of flux guiding elements. Thus, the at least two of the at least two flux guiding elements assume a dual function here. They act as a magnetic core for both the first sensor winding and / or the second sensor winding and as a magnetic core orFlux guide element for the energy transmission winding. Thus, no separate flux guide element is required for the sensor winding, which leads to simplified manufacturing. A sensor winding can be arranged around a support element. A support element can be made of an electrically non-conductive and magnetically neutral material. A support element can be arranged between two flux guide elements. A support element can be formed separately or be part of a larger support element, for example a support element that carries the flux guide elements. A support element can have a lower height than the flux guide elements between which it is arranged. Height here refers to the extension in the dimension perpendicular to the substrate. Preferably, the first sensor winding and the second sensor winding are each arranged in a gap between at least two of the at least two flux guide elements.

[0020] The arrangement of a sensor winding in a gap between two flux-guiding elements here means that the sensor winding extends at least partially and at least in part of the gap. The gap can be longer than the sensor winding, or the sensor winding can be longer than the gap, or the sensor winding can be the same length as the gap. A gap can be formed between two flux-guiding elements. A gap can also extend across multiple flux-guiding elements. For example, a gap can be formed between two by two flux-guiding elements. A gap can therefore continue after a gap between two further flux-guiding elements.

[0021] An inductive charging device according to the invention is preferably a mobile inductive charging device which is arranged on and / or in a vehicle or a stationary inductive charging device.

[0022] A stationary inductive charging device is the non-mobile part of a vehicle charging system, i.e. the part that does not move with the vehicle.

[0023] A stationary inductive charging device can preferably be located on, at, or in a floor. This can be an inductive charging device applied to the ground or an inductive charging device sunk into a subsurface or into the ground. A floor can be a roadway, a parking lot surface, a garage floor, a floor in a parking garage, or another building. Alternatively, a stationary inductive charging device can also be located on walls or the like. It is also possible for it to be a stationary inductive charging device for a dynamic inductive charging process. During a dynamic inductive charging process, an energy storage device of a vehicle can be charged while the vehicle is moving. For example, in this case, the stationary inductive charging device can extend along the roadway under, in, or on the road surface.

[0024] A mobile inductive charging device can be installed on and / or in a vehicle. Generally speaking, this refers to the part of a vehicle charging system that moves with the vehicle.

[0025] It is preferred that the first sensor winding has a first radial longitudinal direction and the second sensor winding has a second radial longitudinal direction and the first radial longitudinal direction and the second radial longitudinal direction are each arranged at an angle of 45° + / - 10°, preferably at an angle of 45°, to the longitudinal direction of the vehicle and the first radial longitudinal direction and the second radial longitudinal direction intersect at an angle of 70°-110°, preferably perpendicularly.

[0026] In general, a winding extends in at least two dimensions around an axis. The main extension direction perpendicular to the winding axis is referred to here as the radial longitudinal direction. Thus, for a winding with a rectangular, non-square cross-section, the main extension direction runs along or parallel to the longer side of the rectangle. For a winding with an elliptical cross-section, the radial longitudinal direction runs along or parallel to the main axis of the ellipse. The radial longitudinal direction of a sensor winding according to the invention can preferably lie in a plane that extends parallel to the ground.

[0027] A corresponding arrangement of the angles of the radial longitudinal directions is advantageous for the highest possible sensitivity in detection and the simplest possible calculation of the position deviation between the vehicle and the stationary inductive charging device.

[0028] If the two angles between the respective radial longitudinal direction of the sensor windings and the longitudinal direction of the vehicle are approximately equal, this means that the sensor windings are arranged symmetrically to the direction of travel.

[0029] When the term “longitudinal direction of the vehicle” is used in relation to a stationary inductive charging device, it refers to the “longitudinal direction of the vehicle” to be achieved when the positioning process is successfully completed, i.e. the “longitudinal direction of the vehicle” as it is positioned during the energy transfer process.

[0030] This is particularly advantageous because the sensor windings are specifically designed to detect a right-left positional deviation between the inductive charging device in the vehicle and the stationary inductive charging device. Due to the symmetrical arrangement of the sensor windings with respect to the direction of travel, the voltages induced in the sensor windings are also symmetrical for equally large positional deviations to the right or left, thus enabling a relatively simple calculation of the positional deviations from the induced voltages. If the two angles are 45°, the two sensor windings are at a 90° angle to each other, which is ideal for optimal evaluation of the sensor signals.

[0031] It is preferred that the first sensor winding has a first radial longitudinal direction and the second sensor winding has a second radial longitudinal direction and that the first radial longitudinal direction and the second radial longitudinal direction intersect in the region of the area spanned by the energy transmission winding.

[0032] The area spanned by the power transmission winding refers to the area spanned by the power transmission winding in the plane perpendicular to its winding axis. This explicitly includes the inner area of ​​the power transmission winding, where no winding is present, but not the area located outside the power transmission winding.

[0033] It's important to note that "direction," such as "radial longitudinal direction," always refers to a straight line and not a distance defined by the beginning and end of the component. The fact that the two radial longitudinal directions of the sensor windings intersect within the area spanned by the power transmission winding does not necessarily mean that the sensor windings themselves intersect; it's also possible that they would only intersect in the extension.

[0034] Arranging the two sensor windings so that the two radial longitudinal directions intersect in the area spanned by the energy transfer winding offers advantages for the evaluation of the two sensor signals. When a signal is sent from the stationary inductive charging device for positioning, a voltage is induced in each of the two windings. The ratio of the two voltages allows direct conclusions to be drawn about the positional deviation between the vehicle and the stationary inductive charging device. It is particularly advantageous if the two sensor windings are arranged symmetrically with respect to the longitudinal direction of the vehicle.

[0035] It is particularly preferred that the first radial longitudinal direction and the second radial longitudinal direction intersect at least approximately in the center of the energy transmission winding.

[0036] The center of the power transmission winding refers to the area a few centimeters around the geometric center of the power transmission winding in the plane perpendicular to the winding axis of the power transmission winding. "Center" here refers only to the two dimensions in which the power transmission winding primarily extends, for example, the driving plane. The intersection does not have to be centrally located in the power transmission winding in the direction in which the power transfer takes place; for example, a central location does not occur in relation to the height of the vehicle.

[0037] This is advantageous because the two radial longitudinal directions of the two sensor windings are tilted to the longitudinal direction of the vehicle by an angle that is advantageous for optimal detection of a positional deviation between the vehicle and the stationary inductive charging device.

[0038] In addition, the sensor windings are arranged in relation to the energy transmission winding in such a way that the lowest possible voltages are induced in the sensor windings during the energy transmission process.

[0039] In one embodiment, the two sensor windings intersect at least approximately in the center of the energy transfer winding. The fact that only the radial longitudinal directions of the two sensor windings intersect approximately in the center of the energy transfer winding is a weaker condition. In this case, it is also possible for the two sensor windings to be relatively short and arranged in a "V" shape. If these two sensor windings are notionally extended in their radial longitudinal direction, these radial longitudinal directions intersect, but not the two sensor windings themselves. The fact that the two sensor windings themselves intersect is a stricter condition. In this case, the sensor windings are longer than in a "V"-shaped arrangement and actually intersect. The arrangement is "X"-shaped.In this embodiment, the sensor windings have a larger area in which voltage is induced than in embodiments where only the radial longitudinal directions of the sensor windings intersect in the extension, and more voltage can be induced. In this case, an actual crossing of the sensor windings occurs, rather than merely a crossing in the extension of the sensor windings.

[0040] It is advantageous if, in this embodiment, the two sensor windings are arranged point-symmetrically to the center of the energy transmission winding.

[0041] In an alternative preferred embodiment, the inductive charging device has at least four sensor windings, two of which are arranged on opposite sides of the center of the energy transmission winding and all radial longitudinal directions run approximately through the center of the energy transmission winding and / or the four radial longitudinal directions of the four sensor windings each form an angle of 45° + / - 10°, preferably 45°, with the longitudinal direction of the vehicle.

[0042] Thus, the four sensor windings are arranged like a cross around the center of the energy transmission winding, whereby the center of the energy transmission winding itself is free of a sensor winding.

[0043] Preferably, the four sensor windings can be arranged radially at equal intervals around the center of the energy transmission winding and can be arranged at approximately the same angle to one another. For example, the angle between the respective radial longitudinal direction of a sensor winding and the radial longitudinal direction of the adjacent sensor winding can always be 45° + / - 10°, preferably 45°.

[0044] This embodiment is advantageous over the embodiment with only two sensor windings, as this arrangement allows for more efficient use of the installation space and allows for more windings per sensor winding. Overall, more voltage is induced. Compared to the embodiment with two intersecting sensor windings, it also offers the advantage that the center of the energy transmission winding remains free of a sensor winding, allowing stabilizing elements to be incorporated in this area.

[0045] The four sensor windings can be interconnected, preferably in series. Particularly preferred is the two diagonally opposite sensor windings being interconnected in series.

[0046] It is advantageous that the first radial longitudinal direction and the second radial longitudinal direction are at least approximately parallel to the main direction of the magnetic field lines that form during energy transfer in and / or near the flux guiding elements in the area covered by the sensor winding.

[0047] The main direction of the magnetic field lines at each location refers to the direction in which the magnetic field lines extend primarily in or close to the flux guide element. It is particularly important here that - if the flux guidance is provided by several flux guide elements arranged next to one another and separated by gaps - the magnetic field also develops in the gaps. The magnetic field also develops accordingly next to a flux guide element. The direction of the magnetic field lines largely corresponds to the direction of the magnetic field lines in the adjacent flux guide elements. The aim here is not to show the exact course of the magnetic field lines through the sensor winding, but rather the radial longitudinal directions should be oriented according to the course of the magnetic field lines in the area of ​​the sensor winding.During energy transfer from the stationary inductive charging device to the inductive charging device in the vehicle, the magnetic field is guided in one or more flux guide elements. If one or more flux guide elements are plate-shaped, a magnetic field with magnetic field lines that run approximately radially with respect to the energy transfer winding is created in the flux guide elements and in the gaps or other areas between the flux guide elements during the charging process. Although a voltage is to be induced in the sensor windings during the positioning process in order to calculate a positional deviation between the vehicle and the stationary inductive charging device, the magnetic fields are significantly higher during the charging process, and it is therefore important that as little voltage as possible is induced in the sensor windings to avoid damaging them or neighboring components.The field component perpendicular to the radial longitudinal direction of the sensor windings is relevant for the induced voltage. Therefore, if the sensor winding is arranged in such a way that the radial longitudinal direction of the sensor winding is at least approximately parallel to the main direction of the magnetic field lines in or near the flux guide elements during the charging process, no or only a small voltage is induced in the sensor winding.

[0048] Alternatively, it is also possible for the first radial longitudinal direction and the second radial longitudinal direction to intersect outside the center of the energy transmission winding.

[0049] Preferably, the energy transmission winding is designed as a flat coil and / or the first sensor winding and the second sensor winding as a solenoid. A flat coil can be a spiral flat coil, in particular a circular spiral flat coil or a rectangular spiral flat coil. A spiral flat coil can be wound in the form of an Archimedean spiral. The winding shape can be circular (circular spiral flat coil), but other shapes are also possible, such as square or rectangular, or even similar to a rectangle with rounded corners (rectangular spiral flat coil). The spiral lies in a plane. A flat coil is particularly suitable for transmitting the highest possible power between a stationary inductive charging device and an inductive charging device in the vehicle.

[0050] A solenoid is also called a cylindrical coil or solenoid coil. A solenoid can be wound in the shape of a helix or a cylindrical spiral. However, the winding shape does not necessarily have to be circular, but can also have other shapes, such as square or rectangular, or even similar to a rectangle with rounded corners. The important difference from a flat coil is that the windings are not in a single plane, but rather extend along an axis. However, two or more windings can also run parallel and thus be in the same plane, perpendicular to the axis.

[0051] The shape of the solenoid is well suited to detect a signal sent by the stationary inductive charging device during the positioning process.

[0052] In a further preferred embodiment, a plurality of flux guide elements are arranged radially around the center of the energy transmission winding, with gaps between the flux guide elements also extending radially.

[0053] From a manufacturing perspective, it is either impossible or very difficult to produce a large flux guide element that covers the entire surface of the energy transfer coil or even extends beyond it. Therefore, several smaller flux guide elements must usually be placed next to one another. In this case, it is possible to use rectangular flux guide elements. These are easier to manufacture. There are then always smaller gaps between the flux guide elements. These can negatively influence the guidance of the magnetic field. With rectangular flux guide elements, the gaps between the flux guide elements will always run partly perpendicular to or at an angle to the magnetic field lines. It is therefore advantageous if the gaps between the flux guide elements also run radially and thus influence the guidance of the magnetic field as little as possible.

[0054] Preferably, the first sensor winding and the second sensor winding are formed by conductor tracks which are applied to at least one printed circuit board, preferably to at least two printed circuit boards, in particular to at least one upper printed circuit board and at least one lower printed circuit board.

[0055] Here, the turns of a sensor winding are realized in the form of conductor tracks on printed circuit boards.

[0056] The conductor tracks can be made of copper, for example.

[0057] The conductor tracks can be multi-layered, preferably double-layered. The cross-section of such a conductor track can be adapted much more flexibly to the constraints imposed by the limited installation space. In particular, it is possible to design the cross-section of the conductor tracks as a rectangle with a low height, with the height in this case being perpendicular to the substrate.

[0058] Implementing a sensor winding using conductor tracks on printed circuit boards makes it possible to significantly reduce the height of the sensor winding compared to conventional windings, such as those based on high-frequency stranded conductors. This type of sensor winding therefore requires less installation space, particularly in the dimension along the winding axis of the power transmission winding, which is the most critical in terms of installation space. The manufacturing process for a sensor winding based on printed circuit boards is also simpler compared to conventional sensor windings with wound high-frequency stranded conductors.

[0059] In a preferred variant, at least one of the at least one printed circuit boards has a smaller width in a longitudinal region of the printed circuit board than in a contact region of the printed circuit board. Here, the longitudinal region of a printed circuit board is the region that runs along the radial longitudinal direction of the sensor winding. The contact region of the printed circuit boards is located at both ends of the longitudinal region of the printed circuit boards.

[0060] Here it is possible to contact the conductor tracks of different circuit boards with each other.

[0061] The width does not have to be reduced across the entire length. It can also be reduced only in certain sections, or only certain areas along the width are left out. The key to this variant is that PCB material is saved by not making the PCBs entirely from PCB material along the entire length.

[0062] This shape minimizes the amount of insulating circuit board material. Since the insulating circuit board material also has poor thermal conductivity, this optimized shape allows for more waste heat to be dissipated from the various components of the inductive charging device.

[0063] Furthermore, it is possible that only one of the two contact areas is widened compared to the longitudinal area and the other contact area is designed with the same width as the longitudinal area or even tapers towards the end.

[0064] In a preferred embodiment, the first sensor winding and the second sensor winding consist of upper conductive tracks on an upper circuit board and lower conductive tracks on a lower circuit board.

[0065] The conductor tracks on the upper circuit board can be connected to the conductor tracks on the lower circuit board to create a spiral winding.

[0066] The upper conductor track can be arranged predominantly above one or more support elements, and the lower conductor track can be arranged predominantly below one or more support elements. The terms "above" and "below" or "upper" and "lower" refer to the arrangement of an inductive charging device that extends predominantly parallel to the substrate. If, for example, a charging device is arranged parallel to a wall, the terms should still be understood as "on one side of the flux-guiding elements and / or the support elements" and "on the other side of the flux-guiding elements and / or the support elements," without departing from the scope of the invention.

[0067] In one variant, the upper conductor tracks are soldered to the lower conductor tracks.

[0068] Preferably, the upper conductor tracks are connected to the lower conductor tracks via through-plated and / or surface-soldered plug and socket strips.

[0069] Using plug and socket connectors, it's possible to create a connection without soldering the circuit boards during assembly of the inductive charging device. This offers significant advantages during manufacturing.

[0070] This is especially the case with the version with the through-hole plug and socket connectors.

[0071] However, the use of plug and socket strips can also involve a soldering process when using surface-mounted or surface-soldered (surface-mounted device, SMD) plug and socket strips, which is, however, significantly simpler than a soldering process without the corresponding plug and socket devices.

[0072] In an alternative preferred variant, the upper conductor tracks are connected to the lower conductor tracks via flexible circuit boards.

[0073] The upper and lower circuit boards can still be designed as rigid circuit boards. The flexible circuit boards provide the connection via the vertical end faces and thus complete the winding for the coil around the carrier element. This creates a combination of rigid and flexible circuit boards. This combination is also known as rigid-flex circuit boards. This is also a variant that allows for simpler and more suitable manufacturing than on-site soldering.

[0074] In a further advantageous embodiment, the upper circuit boards are connected to one another. Preferably, the upper circuit boards are designed as a common upper circuit board. Since the circuit boards themselves only represent the non-conductive base for the actual conductor tracks, no connection is established between the various sensor windings, which would influence their electromagnetic properties. Because the upper circuit boards are combined as a common circuit board, a mechanically much more stable component can be produced and the assembly of just one component instead of an upper circuit board for each sensor winding is also much easier. Using such a common upper circuit board, it is also easier to electrically interconnect the sensor windings, for example by connecting them in series or in parallel.This means fewer connecting conductors need to be routed to a more distant electronic device. In this variant, the area around the center of the sensor winding can be left out, allowing support elements to be arranged there. In this case, the common upper circuit board is designed in a ring shape in the center.

[0075] Another possibility is for the upper circuit boards to be clipped onto an inner circuit board ring, thus connecting them to one another. By clipping, we mean that a detachable connection is created between the upper circuit boards and the circuit board ring by hooking, clamping, or plugging them in. The first sensor winding and / or the second sensor winding can be electrically connected to an electronic device. The electronic device can advantageously be arranged on or near the shielding and / or the cooling plate. The electronic device can then further process and / or evaluate the sensor signals from the sensor windings. For this purpose, the connecting lines required to connect the sensor winding to the electronic device can be routed through other components, such as a shield and / or the cooling plate.This passed-through part of the connecting line can be implemented analogously to the contact area of ​​the sensor winding in the form of pin strips or in the form of flexible conductor tracks. The respective circuit board can be of any shape and / or dimension. Preferably, the respective circuit board has a shape extending in the direction of the windings and a width that is transverse to the longitudinal direction of the windings, between 20 mm and 60 mm, in particular between 30 mm and 50 mm, preferably 40 mm. This means that several windings, in particular next to one another, can be located thereon. Preferably, the respective circuit board has several windings between 8 and 23, in particular between 11 and 19, preferably 15.

[0076] It may be advantageous to reduce the number of required feedthroughs. This can be achieved by connecting two or more of the sensor windings in series. Alternatively, or additionally, several connecting cables can be bundled and routed through a feedthrough.

[0077] In an alternative advantageous embodiment, the first sensor winding and the second sensor winding are designed as a stranded wire, in particular as a high-frequency stranded wire or as a wire.

[0078] A high-frequency stranded wire consists of several mutually insulated wires. This offers advantages because at high frequencies, current flows primarily near the surface of a conductor, and the implementation with many individual conductors provides as much conductor surface area as possible. The term "wire" refers to the implementation as an insulated single wire, which is then also wound in the form of multiple turns. One advantage of implementing sensor windings as high-frequency stranded wire or as a wire is that it is a proven and simple manufacturing method.

[0079] For this embodiment, an additional mechanical support structure can be used to prevent the high-frequency strand or wire from slipping on the carrier element.

[0080] Alternatively, it is possible to glue the high-frequency strand or wire to the carrier element to prevent slipping.

[0081] A spacer structure can also be used to ensure a defined distance between the individual turns of the sensor winding.

[0082] It is also conceivable not to use a carrier element, but to fill the gap with a potting or adhesive material and to arrange the sensor winding(s) in and / or around it.

[0083] Preferred embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description, wherein the same reference numerals refer to the same or similar or functionally identical components.

[0084] It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

[0085] It shows, schematically

[0086] Fig. 1 is a highly simplified representation of a vehicle with an inductive charging device, Fig. 2 is a sectional view of an inductive charging device for a vehicle charging system,

[0087] Fig. 3 is a plan view of an inductive charging device according to the invention,

[0088] Fig. 4 is a plan view of an inductive charging device according to the invention in another embodiment,

[0089] Fig. 5 is a sectional view of an inductive charging device according to the invention as shown in Fig. 3 or Fig. 4, cut along the first radial longitudinal direction 11a shown there,

[0090] Fig. 6 is a schematic representation of the directions in a winding.

[0091] Fig. 7 is a perspective view of an alternative sensor winding arranged around a support element,

[0092] Fig. 8 Top view of two versions of circuit boards for sensor windings,

[0093] If a part in the figures is designated by reference numerals separated by a comma, this means that both descriptions apply to the concrete designated part. In Fig. 1, 1, 1a means, for example: This is an inductive charging device and it is also a mobile inductive charging device. Fig. 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 and the energy storage device of the vehicle 3 can be charged as a result. 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 stationary inductive charging device 1b arranged on the ground in Fig. 1 can alternatively 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 road surface.

[0094] Fig. 2 shows a lateral section through an inductive charging device 1, 1a which includes several flux guiding elements 5 and an energy transmission winding 4, 4a and is mounted on a vehicle 2.

[0095] A corresponding arrangement exists for a stationary inductive charging device 1b, except that it is arranged on a surface instead of on a vehicle 2 (not shown).

[0096] Fig. 3 shows a plan view of an inductive charging device 1 according to the invention. This can be a mobile inductive charging device 1a or a stationary inductive charging device 1b. In the present exemplary embodiment, eight flux guiding elements 5 are shown, which are arranged radially around the center 7 of the energy transmission winding 4 in the plane. Narrow gaps 27 are located between the flux guiding elements 5. The gaps also run radially around the center 7, thus running approximately in the main direction of the magnetic field lines that arise during energy transmission in the flux guiding elements 5. The energy transmission winding 4, which is concealed by the flux guiding elements 5 in the plan view, is indicated by dashed lines. The energy transmission winding 4 is a flat coil 10 here.A first sensor winding 9, 9a is arranged in one of the gaps 27 between two of the flux guide elements 5, and a second sensor winding 9, 9b is arranged in another gap 27. The sensor windings 9 are designed here as solenoids, also called cylindrical coils. The first sensor winding 9a is arranged axially symmetrically to the second sensor winding 9b with respect to the longitudinal direction of the vehicle 6. 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 12 between the first radial longitudinal direction 11a and the longitudinal direction.

[0097] 6 of the vehicle 2 is at least approximately equal to the angle 13 between the second radial longitudinal direction 11 b and the longitudinal direction of the vehicle 6. The first radial longitudinal direction 11 a and the second radial longitudinal direction 11 b intersect or cross at least approximately in the center

[0098] 7 of the energy transmission winding 4. The first radial longitudinal direction 11 a and the second radial longitudinal direction 11 b run radially outwards from the center 7 of the energy transmission winding 4.

[0099] 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 guiding elements 5 perform the function of flux guiding. In the charging state, the field lines of the magnetic field run approximately radially in them and in the gaps 27 between them. Since the first radial longitudinal direction 11a and the second radial longitudinal direction 11b are also aligned radially and thus at least approximately parallel to the magnetic field lines 14, only relatively little or no voltage is induced in the first sensor winding 9a and the second sensor winding 9b. This is important, since the high power levels of the energy transfer and thus the high flux densities could otherwise easily lead to the sensor windings being destroyed. Additional effort to prevent the arrangement from being destroyed is therefore unnecessary.Advantageously—contrary to the rough schematic drawing—the flux guide elements 5 can also be designed with rounded corners and edges to prevent unwanted peaks in the magnetic fields. Fig. 4 shows a plan view of another embodiment of an inductive charging device 1 according to the invention. In contrast to the embodiment shown in Fig. 3, the sensor windings 9a, 9b are shorter here and therefore do not extend over the entire area spanned by the flux guide elements 5.

[0100] Fig. 5 shows a sectional view cut in Fig. 3 or Fig. 4 along the first radial longitudinal direction 11a. The first sensor winding 9a is arranged here around a support element 16. The support element 16 can, in particular, be designed to be lower in height than the flux guide elements 5. Thus, the sensor windings 9a, 9b can be arranged in the gaps 27 without increasing the height of the inductive charging device.

[0101] For clarity, this illustration does not show the beginning and end of the winding exposed to the outside. Of course, the beginning and end of the winding are also exposed to the outside—although not necessarily in the plane of the section—and can be electrically connected there, allowing the winding to be energized accordingly.

[0102] In Fig. 4 and 5, the sensor windings 9a, 9b are only indicated roughly schematically. Fig. 6 shows how a sensor winding 9 actually runs, for example, around a support element 16. Fig. 6 also shows schematically how the directions, in particular the radial longitudinal direction 11, are defined in a winding, in particular in a sensor winding 9. The example in Fig. 6 shows a cylindrical coil with five turns. The direction along which the winding was wound is the winding axis 17. The coil here has a rectangular, not square, cross-section. The direction along the longer side of the rectangle is called the radial longitudinal direction 11 here. If the cross-section is not rectangular, but elliptical, the radial longitudinal direction 11 runs along the main axis of the ellipse. The sensor winding 9 can be designed, for example, as a high-frequency stranded wire 15.

[0103] Fig. 7 shows a perspective view of an alternative embodiment of a carrier element 16 with a sensor winding 9. Here, the sensor winding 9 is designed in the form of printed circuit boards 18 with conductor tracks 22. The upper conductor tracks 22a on the upper circuit board 18a are connected to the lower conductor tracks 22b on the lower circuit board 18b in such a way that they form a continuous winding.

[0104] Fig. 8 shows two different possibilities for an optimized shape of a printed circuit board 18. The width of the printed circuit board 19 is significantly smaller in the longitudinal region 20 of the printed circuit board than in the contact region of the printed circuit board 21. The longitudinal region 20 of the printed circuit board is the region that runs along the top or bottom of the flux guide elements 5. In the right-hand embodiment, one of the two contact regions 21 is additionally designed with a semicircular, tapered end.

[0105] Reference list

[0106] 1 inductive charging device

[0107] 1a mobile inductive charging device

[0108] 1 b stationary inductive charging device

[0109] 2 vehicles

[0110] 3 Vehicle energy storage

[0111] 4 Energy transmission winding

[0112] 5 Flow guide element

[0113] 6 Longitudinal direction of the vehicle

[0114] 7 Center of the energy transmission winding

[0115] 8 Vehicle charging system

[0116] 9 Sensor winding

[0117] 9a first sensor winding

[0118] 9b second sensor winding

[0119] 10 flat coil

[0120] 11 radial longitudinal direction

[0121] 11 a first radial longitudinal direction

[0122] 11 b second radial longitudinal direction

[0123] 12 first angle

[0124] 13 second angle

[0125] 14 Main direction of the magnetic field lines

[0126] 15 strands

[0127] 16 support element

[0128] 17 Winding axis

[0129] 18 circuit board

[0130] 18a upper circuit board

[0131] 18b lower circuit board

[0132] 19 Width of the circuit board

[0133] 20 Longitudinal area of ​​the printed circuit board Contact area of ​​the printed circuit board Conductor tracks a upper conductor tracks b lower conductor tracks Gap between flux guide elements

Claims

Claims 1. Inductive charging device (1) for a vehicle charging system (8) with an energy transmission winding (4) and at least two flux guiding elements (5) and at least one first sensor winding (9a) and one second sensor winding (9b), with the following features: - the flux guiding elements (5) are suitable for guiding a magnetic field during an energy transfer which takes place between a further inductive charging device (1) and the energy transfer winding (4), and - the first sensor winding (9a) and the second sensor winding (9b) are each arranged between at least two of the at least two flux guiding elements (5).

2. Inductive charging device (1) according to claim 1, characterized in that the first sensor winding (9a) and the second sensor winding (9b) are each arranged in a gap (27) between at least two of the at least two flux guiding elements (5).

3. Inductive charging device (1) according to claim 1 or claim 2, characterized in that - the inductive charging device (1) is a mobile inductive charging device (1a) which is arranged on and / or in a vehicle (2), or that - the inductive charging device (1 ) is a stationary inductive charging device (1 b).

4. Inductive charging device (1) according to one of the preceding claims, characterized in that - the first sensor winding (9a) has a first radial longitudinal direction (11a), - the second sensor winding (9b) has a second radial longitudinal direction (11b), - the first radial longitudinal direction (11a) is arranged at an angle of 45° + / - 10°, preferably at an angle of 45°, to the longitudinal direction of the vehicle (6), - the second radial longitudinal direction (11b) at an angle of 45° + / -10 0, preferably arranged at an angle of 45° to the longitudinal direction of the vehicle (6) and - the first radial longitudinal direction (11a) and the second radial longitudinal direction (11b) intersect at an angle of 70°-110°, preferably perpendicularly.

5. Inductive charging device (1) according to one of the preceding claims, characterized in that - 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) and - the first radial longitudinal direction (11a) and the second radial longitudinal direction (11b) intersect in the area of ​​the surface spanned by the energy transmission winding (4).

6. Inductive charging device (1) according to one of claims 4-5, characterized in that the first radial longitudinal direction (11a) and the second radial longitudinal direction (11b) at least approximately in the center (7) of the energy transmission winding (4).

7. Inductive charging device (1) according to one of claims 4-6, characterized in that the first radial longitudinal direction (11a) and the second radial longitudinal direction (11b) are at least approximately parallel to the main direction of the magnetic field lines (14) which form during the energy transfer in and / or near the flux guiding elements (5) in the area covered by the sensor winding.

8. Inductive charging device (1) according to one of claims 4-7, characterized in that the first radial longitudinal direction (11a) and the second radial longitudinal direction (11b) intersect outside the center (7) of the energy transmission winding (4).

9. Inductive charging device (1) according to one of the preceding claims, characterized in that the energy transmission winding (4) is designed as a flat coil (10) and / or the first sensor winding (9a) and the second sensor winding (9b) are designed as a solenoid.

10. Inductive charging device (1) according to one of claims 2-9, characterized in that a plurality of flux guiding elements (5) are arranged radially around the center (7) of the energy transmission winding (4), wherein the gaps (27) between the flux guiding elements (5) also run radially.

11. Inductive charging device (1) according to one of the preceding claims, characterized in that the first sensor winding (9a) and / or the second sensor winding (9b) are formed by conductor tracks (22) which are applied to at least one printed circuit board (18), preferably to at least two printed circuit boards (18a, 18b), in particular to at least one upper printed circuit board (18a) and at least one lower printed circuit board (18b).

12. Inductive charging device (1) according to claim 11, characterized in that at least one of the at least one printed circuit boards (18) has a smaller width (19) in a longitudinal region of the printed circuit board (20) than in a contact region of the printed circuit board (21).

13. Inductive charging device (1) according to claim 11 or claim 12, characterized in that the first sensor winding (9a) and the second sensor winding (9b) consist of upper conductor tracks (22a) on the at least one upper circuit board (18a) and of lower conductor tracks (22b) on the at least one lower circuit board (18b).

14. Inductive charging device (1) according to one of claims 1 - 10, characterized in that the first sensor winding (9a) and the second sensor winding (9b) are designed as a stranded wire, in particular as a high-frequency stranded wire (15) or as a wire. *****

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