Inductive charging device for vehicle

Abstract

The invention relates to an inductive charging device for a vehicle charging system, comprising an energy transfer winding and at least one magnetic flux element and at least one positioning signal winding. The positioning signal winding is embodied as a solenoid having a winding axis in the vehicle longitudinal direction or in the target vehicle longitudinal direction, and the magnetic flux guiding element is suitable for guiding a magnetic field during an energy transfer process occurring between the further inductive charging device and the energy transfer winding. The positioning signal winding surrounds at least one of the at least one magnetic flux guiding elements and surrounds the energy transfer winding.

Description

Technical Field

[0001] The invention relates to an inductive charging device for a vehicle charging system and to a vehicle charging system according to the generic nature of the independent claims. Background Art

[0002] DE 102018210726 A1 describes a positioning antenna for positioning an inductive secondary unit relative to a primary unit. Here, the coil core of the positioning antenna is simultaneously used as the coil core of a charging coil for inductive energy transmission. The positioning antenna can generate or receive a measurement magnetic field for positioning. The positioning antenna comprises a plurality of windings of a conductor and is implemented as a cylindrical coil consisting of a flat ribbon cable. The positioning antenna has an advantageous directional effect. Here, the positioning antenna must always be positioned between the coil core and the charging coil with great effort. In addition, for a simple positioning antenna with an advantageous directional effect, a corresponding advantageous receiver on the mating side is not shown. Summary of the invention

[0003] In the present case, an inductive charging device for a vehicle charging system is proposed, which has an energy transmission winding and at least one flux guiding element and at least one positioning signal winding, wherein the positioning signal winding is implemented as a solenoid, which has a winding axis in the longitudinal direction of the vehicle or in the longitudinal direction of the target vehicle, and the positioning signal winding surrounds at least one of the at least one flux guiding elements and surrounds the energy transmission winding.

[0004] In the case of inductive charging, energy is transferred in the form of a magnetic field between two inductive charging devices, usually between a stationary inductive charging device and a mobile inductive charging device.

[0005] The term "inductive charging device" therefore refers here only to one of the at least two parts which is necessary for the inductive energy transfer process. During the inductive energy transfer process, the energy transfer winding generates an alternating magnetic field in the inductive charging device. This alternating magnetic field induces a voltage in the further energy transfer winding of the further inductive charging device. Thus, for this specific energy transfer process, the further inductive charging device serves as a counterpart. Energy is transmitted wirelessly and received via the induced voltage.

[0006] The inductive charging device can be used for inductive charging of vehicles. In principle, the inductive charging device according to the invention can be used for any type of land vehicle, water vehicle or aircraft that has an electric drive or a hybrid drive. In particular, passenger cars, buses and trucks are mentioned here.

[0007] The vehicle charging system includes at least one mobile inductive charging device and a further inductive charging device, usually a stationary inductive charging device. The mobile inductive charging device can be installed on and / or in the vehicle, for example.

[0008] An inductive charging device on and / or in a vehicle is therefore suitable for receiving a magnetic field and supplying electrical energy to an energy store of the vehicle, for example a battery or accumulator in the vehicle.

[0009] In principle, the vehicle charging system can also be used for bidirectional charging. Here, the vehicle can also temporarily feed energy from the energy storage device into the power grid via the vehicle charging system.

[0010] The inductive charging device has an energy transmission winding that can efficiently receive a magnetic field from another energy transmission winding and / or can emit a magnetic field during an energy transmission process. Preferably, a power of 3 kW to 500 kW can be transmitted, particularly preferably a power of 3 kW to 50 kW can be transmitted.

[0011] 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 optional further 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 windings, wherein one winding represents a complete revolution of the conductor. However, in general, a winding can also consist of only less than one winding, such as 0.5 windings. Of course, a non-integer number of windings, such as 2.5 windings, is also possible.

[0012] The energy transmission winding can be designed in various forms and can be composed, for example, of a high-frequency litz wire having a diameter of between 0.5 mm and 10 mm, which is preferably composed of copper.

[0013] The energy transmission winding can be implemented as a flat coil. The flat coil can be a spiral flat coil, in particular a circular spiral flat coil or a rectangular spiral flat coil. The spiral flat coil can be wound in the form of an Archimedean spiral. In this case, the winding shape can be circular (circular spiral flat coil), but other shapes, such as square-like or rectangular-like or also rectangular-like with rounded corners, are also possible (rectangular spiral flat coil). In this case, the spiral is located in a plane. Flat coils are particularly suitable for transmitting the highest possible power between a stationary inductive charging device and a mobile inductive charging device in a vehicle.

[0014] Alternatively, the energy transmission winding can be designed similarly to a flat coil in a manner distributed over a plurality of planes, for example three planes, in the manner of a truncated pyramid.

[0015] The flux guiding element is suitable for guiding a magnetic field in a predetermined manner. The flux guiding element has a high magnetic permeability, wherein μ r >1, preferably μ r >50, particularly preferably μ r >100. The flux guiding element is a magnetic core for the energy transmission winding. In particular, the magnetic field is influenced by the high magnetic permeability in such a way that the largest possible magnetic flux is transmitted to the energy transmission winding. With otherwise identical parameters, the energy transmission winding receives a larger magnetic flux with the flux guiding element than without the flux guiding element. The flux guiding element can be made of a ferromagnetic material, or preferably of a ferrimagnetic material, particularly preferably of a ferrite. The flux guiding element can preferably be implemented in a plate-shaped manner - in the form of a planar core - and can be arranged in the inductive charging device on the side of the energy transmission winding that faces away from the mating side, i.e., away from the other inductive charging device.

[0016] The positioning signal winding can send out a positioning signal during the positioning process. For example, the positioning signal winding can generate an alternating magnetic field with a certain frequency based on an AC voltage. In principle, the energy transmission winding can also send out a positioning signal, but it is advantageous to use a separate positioning signal winding to generate the positioning signal, as proposed herein. In particular, the positioning signal winding can generate a magnetic field that is more suitable for positioning and can achieve a larger range of action, especially with the same power. The energy transmission winding is designed so that the energy transmission winding is coupled to the corresponding matching part as well as possible. Therefore, in general, the energy transmission winding does not have a large range of action in terms of sending or receiving a magnetic field in the longitudinal direction of the vehicle or the longitudinal direction of the target vehicle. However, this is crucial for the positioning process.

[0017] During positioning, the maximum possible power of the positioning signal or the maximum possible magnetic field is strongly limited. The maximum possible power or the maximum possible magnetic field is significantly smaller than in the case of energy transfer processes. During the positioning process, no vehicle is located on the stationary inductive charging device. It is therefore possible, for example, for a person to stand on the stationary inductive charging device. In order to keep the magnetic field harmless for people, the magnetic field must not be greater than a magnetic flux density of 27 μT or 6.25 μT, depending on the frequency range.

[0018] With the proposed locating signal winding, a locating signal can be generated which contains limit values ​​or reference values ​​and nevertheless enables a large range.

[0019] Solenoids are also called cylindrical coils or solenoid coils. Solenoids can be wound in the form of a spiral or cylindrical helix. However, the winding shape does not have to be circular, but can also have other shapes, such as square-like or rectangular-like or also rectangular-like with rounded corners. An important difference from a flat coil is that the winding does not lie in one plane, but extends along an axis. However, two or more windings can also extend in parallel and therefore lie in the same plane perpendicular to the axis.

[0020] The stationary inductive charging device has a target vehicle longitudinal direction, which is the direction in which the longitudinal direction of the vehicle should lie after a successful positioning process.

[0021] If the locating signal winding is located in a mobile inductive charging device of the vehicle, the winding axis of the locating signal winding is oriented in the longitudinal direction of the vehicle. If the locating signal winding is located in a stationary inductive charging device, the winding axis of the locating signal winding is oriented in the longitudinal direction of the target vehicle.

[0022] In the proposed arrangement, the flux guidance element takes over the guidance of the magnetic field for energy transmission during the energy transmission process and takes over the guidance of the magnetic field for positioning during the positioning process. The flux guidance element thus takes over a dual function here, which is particularly advantageous because material and installation space can be used efficiently.

[0023] The arrangement of the locating signal winding around at least one of the at least one flux guiding elements and around the energy transmission winding is advantageous because the locating signal winding can be arranged around an otherwise preassembled inductive charging device. In addition, when the locating signal winding is arranged around at least one of the at least one flux guiding elements and around the energy transmission winding, a larger area is opened up by the locating signal winding than when the locating signal winding is arranged only around one or more of the flux guiding elements. Thus, with the same power, the local maximum of the magnetic flux density is further reduced, or in other words, while observing the magnetic flux density reference value or the magnetic flux density limit value, a higher power can be used and thus a larger range of action can be achieved.

[0024] Particularly preferably, the locating signal winding can be arranged around the entire width of the inductive charging device, so that the largest possible area is covered in this way and a magnetic field that is as homogeneous as possible can thus be generated.

[0025] Preferably, the inductive charging device according to the present invention is a mobile inductive charging device arranged on and / or in a vehicle, or a stationary inductive charging device.

[0026] A stationary inductive charger is the non-mobile part of a vehicle's charging system, ie the part that does not move with the vehicle.

[0027] Preferably, the stationary inductive charging device can be located on, at or in the ground. This can be an inductive charging device applied to a substrate or an inductive charging device sunk into a substrate or into the ground. The ground can be a driveway, a parking space surface, a garage floor, a floor in a parking garage or other building. However, as an alternative, the stationary inductive charging device can also be located on a wall or the like.

[0028] It is also possible that this is a stationary inductive charging device for a dynamic inductive charging process. In the case of a dynamic inductive charging process, the energy storage device of the 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 roadway surface.

[0029] The mobile inductive charging device can be arranged on and / or in the vehicle. Quite generally speaking, this is to be understood as the part of the vehicle charging system that moves with the vehicle.

[0030] The positioning signal winding is preferably formed by a conductor track which is applied to at least one printed circuit board, preferably to at least two printed circuit boards.

[0031] In this case, the turns of the positioning signal winding are realized in the form of conductor tracks on a printed circuit board.

[0032] In this case, the conductor track can consist of copper, for example.

[0033] In this case, the conductor track can be embodied in multiple layers, preferably in two layers.

[0034] Here, the cross section of such a conductor track can be adapted more flexibly to the framework conditions predefined by the limited installation space. It is particularly important to implement the cross section of the conductor track as a rectangle with a low height, wherein the height here is in the dimension perpendicular to the substrate.

[0035] The realization of the locating signal winding by means of a conductor track on a printed circuit board makes it possible to significantly reduce the height of the locating signal winding compared to conventional windings, for example based on high-frequency litz wires. As a result, this shape of the locating signal winding requires less installation space, especially in the dimension along the winding axis of the energy transmission winding, which dimension is most critical in terms of installation space.

[0036] Preferably, at least two circuit boards are used to position the signal winding, wherein one circuit board can be arranged on one side of the flux guiding element, for example above, and the other circuit board can be arranged on the other side of the flux guiding element, for example below. In this case, the conductor paths on the two circuit boards are connected via corresponding flexible or non-flexible connections and thus form a winding. Compared with conventional windings with wound high-frequency litz wire conductors, the production method of the winding based on the circuit board is simpler.

[0037] In an alternative advantageous embodiment, the locating signal winding is designed as a litz wire, in particular as a high-frequency litz wire or as a metal wire.

[0038] High-frequency litz wires consist of a plurality of metal wires insulated from one another. This offers advantages, since at high frequencies the current flows mainly near the surface of the conductor, and a design with a plurality of individual conductors provides as much conductor surface as possible.

[0039] In this case, the embodiment as an insulated individual wire, which is likewise wound in the form of a plurality of windings, is referred to as a wire.

[0040] An advantage of implementing the locating signal winding as a high-frequency litz wire or metal wire is a proven and simple manufacturing method.

[0041] Additional mechanical support structures can be used for this embodiment so that the high-frequency strands or wires do not slip off the flux conducting element.

[0042] Alternatively, it is possible to glue the high-frequency litz wire or wire to at least one flux conducting element in order to prevent slipping.

[0043] It is also possible to use spacer structures which ensure a defined distance between the individual turns of the positioning signal winding.

[0044] Preferably, the positioning signal winding at least approximately intersects the winding axis of the energy transmission winding.

[0045] Due to the shape of the energy transmission winding, a winding axis cannot always be assigned directly to the energy transmission winding unambiguously. In this case, the winding axis is assumed to be approximately in the geometric center of the energy transmission winding.

[0046] Such an arrangement is advantageous because during the energy transmission process, as low a voltage as possible should be induced into the locating signal winding, because otherwise the high power occurring during the energy transmission could damage or impair the locating signal winding. The key to this is primarily the main direction of the magnetic flux in the at least one flux guiding element. The main direction of the magnetic field lines at the respective location refers to the direction in which the magnetic field lines extend primarily in the flux guiding element. In this case, the magnetic field lines extend primarily tangentially. It is therefore advantageous to arrange the locating signal winding in a manner that passes approximately through the center of the energy transmission winding, i.e., in a manner that crosses the winding axis of the energy transmission winding, because in this case the conductor of the locating signal winding extends at least approximately parallel to the magnetic field lines and therefore only very low voltages are induced.

[0047] In an alternative preferred embodiment, the locating signal winding is arranged at a distance from the center of the energy transmission winding, in particular close to an edge of the energy transmission winding of the inductive charging device or close to an edge of the inductive charging device.

[0048] In this embodiment, the locating signal winding is displaced relative to the following position: in this position, the locating signal winding intersects the winding axis of the energy transmission winding. That is, the locating signal winding is arranged non-centrally relative to the energy transmission winding, and is also arranged non-centrally in the inductive charging device. Compared with the center of the energy transmission winding, the position signal winding is closer to or farther away from the inductive charging device that forms the matching piece. The locating signal winding is spaced apart from the center of the energy transmission winding in the direction of the edge. Here, "edge" only means that the energy transmission winding or the inductive charging device ends there, and no description is made about the shape of the edge (for example, rounded or non-rounded). In particular, in a mobile inductive charging device, this involves the front edge or rear edge in the case of considering the longitudinal direction of the vehicle, and in a fixed inductive charging device, this involves the front edge or rear edge in the case of considering the longitudinal direction of the target vehicle. For example, the locating signal winding can be arranged close to the edge, or, for example, can be located halfway between the edge and the center of the energy transmission winding.

[0049] An arrangement spaced apart from the center of the energy transmission winding has the advantage that a position can be found for positioning the signal winding at which no further components (eg supporting elements or interruptions in the flux guidance element) impede the arrangement.

[0050] However, in addition to this, the arrangement spaced apart from the center of the energy transmission winding also facilitates the positioning method. If the positioning signal winding is closer to the inductive charging device forming the matching piece than the center of the energy transmission winding, the range of action is increased. If the positioning signal winding is further away from the inductive charging device forming the matching piece than the center of the energy transmission winding, the positioning method can still be performed until a smaller minimum spacing between the two inductive charging devices. In general, for the positioning method with the vehicle charging system according to the present invention, there is not only a maximum range of action, but also in the case of a very small spacing between the two inductive charging devices, a usable signal is no longer obtained from the sensor winding. Therefore, another short-range positioning method can be used, for example, in the following area: in this area, the two inductive charging devices are very close to each other. However, this other short-range positioning method has a very small range of action. In this regard, it is important that the following minimum spacing is as small as possible: until this minimum spacing, the positioning method can be implemented with the inductive charging device according to the present invention. This is achieved in the following way: compared with the center of the energy transmission winding, the positioning signal winding is arranged farther away from the inductive charging device forming the matching piece.

[0051] Furthermore, in the present case, a vehicle charging system is proposed, which has a first inductive charging device and a further inductive charging device, wherein the first inductive charging device has at least one energy transmission winding and at least one flux conducting element and at least one positioning signal winding, and

[0052] The positioning signal winding is implemented as a solenoid having a winding axis in the longitudinal direction of the vehicle or in the target vehicle longitudinal direction, and

[0053] The further inductive charging device has at least one energy transmission winding and at least one magnetic flux guiding element and a first sensor winding having a first radial longitudinal direction and a second sensor winding having a second radial longitudinal direction, the first radial longitudinal direction and the second radial longitudinal direction being arranged at an angle of between 70° and 110° relative to one another, preferably perpendicular to one another, and at an angle of between 35° and 55° relative to the vehicle longitudinal direction or to a target vehicle longitudinal direction, preferably at an angle of 45° relative to the vehicle longitudinal direction or to a target vehicle longitudinal direction.

[0054] Such an implementation and arrangement of the locating signal winding and the sensor winding is not only beneficial to the locating process, but also to the energy transmission process. The locating signal winding is implemented as a solenoid with a winding axis in the longitudinal direction of the vehicle or the longitudinal direction of the target vehicle, and a magnetic field is generated, which has a main direction of the magnetic field lines in the longitudinal direction of the vehicle or the longitudinal direction of the target vehicle. This has the following advantages: Under the same power or the same magnetic field strength, this embodiment achieves a significantly larger range of action for positioning compared to the locating signal generated by the energy transmission winding. In addition, such an orientation of the magnetic field is also particularly suitable for being able to achieve the simplest possible detection of position deviations or angle deviations in the sensor winding.

[0055] The locating signal winding is particularly preferably designed in such a way that it has a particularly large extension in the driving plane and perpendicular to the longitudinal direction of the vehicle or perpendicular to the longitudinal direction of the target vehicle. For example, the locating signal winding can extend over the entire width of the inductive charging device. This results in a largely homogeneous magnetic field with a main direction of the magnetic field lines of the magnetic flux in the longitudinal direction of the vehicle or the longitudinal direction of the target vehicle.

[0056] The proposed arrangement of the sensor windings also facilitates an optimized positioning process. If the sensor windings are arranged symmetrically with respect to the vehicle longitudinal direction or with respect to the target vehicle longitudinal direction, the angular deviation from a uniform magnetic field with a clear main direction of the magnetic flux can be determined by simply comparing the voltages induced in the two sensor windings.

[0057] During the energy transmission process, the lowest possible voltage should be induced both in the locating signal winding and in the energy transmission winding, since otherwise high powers or field strengths during the energy transmission could lead to damage to the corresponding windings.

[0058] The locating signal winding according to the invention and the sensor winding according to the invention can advantageously be arranged in a corresponding inductive charging device in such a way that during energy transmission at the corresponding location, the conductors forming these windings extend predominantly parallel to the main direction of the magnetic flux. This ensures that, during energy transmission, the lowest possible voltage is induced into the corresponding winding.

[0059] In particular, the orientation of the magnetic flux in the respective flux conducting element of the inductive charging device is crucial for this purpose. Preferably, this orientation can extend radially outwards from the center of the respective energy transmitting winding.

[0060] Preferably, the first inductive charging device is a mobile inductive charging device that is situated on and / or in the vehicle, and the further inductive charging device is a stationary inductive charging device, or the first inductive charging device is a stationary inductive charging device and the further inductive charging device is a mobile inductive charging device that is situated on and / or in the vehicle.

[0061] Advantageously, the positioning signal winding surrounds at least one of the at least one flux guiding elements.

[0062] In the proposed arrangement, the flux guidance element guides the magnetic field for energy transmission during the energy transmission process and guides the magnetic field for positioning during the positioning process. The flux guidance element thus performs a dual function.

[0063] Preferably, the locating signal winding at least approximately intersects the winding axis of the energy transmission winding of the first inductive charging device, and the first radial longitudinal direction and the second radial longitudinal direction intersect at least approximately at the center of the energy transmission winding of the further inductive charging device.

[0064] The conductors forming the locating signal winding and the sensor winding extend through the assembly at least approximately parallel to the magnetic field lines which occur during the energy transmission at the respective locations. This ensures that, during the energy transmission, the lowest possible voltage is induced into the respective windings and that these windings are therefore not damaged by the high powers which occur during the energy transmission.

[0065] In this case, the center of the energy transmitting winding is understood to mean a region of a few centimeters around the center of the energy transmitting winding in a plane perpendicular to the winding axis of the energy transmitting winding.

[0066] A corresponding arrangement of the sensor windings is advantageous because the two radial longitudinal directions of the two sensor windings are thus inclined relative to the longitudinal direction of the vehicle at an angle that facilitates optimal detection of an orientation deviation between the vehicle and the stationary inductive charger.

[0067] Furthermore, the sensor winding is thereby arranged relative to the energy transmission winding in such a way that, during the energy transmission process, a voltage which is as low as possible is induced into the sensor winding.

[0068] In one embodiment, the two sensor windings cross at least approximately in the center of the energy transmission winding. It is a weaker condition that only the radial longitudinal directions of the two sensor windings cross approximately in the center of the energy transmission winding. Here, it is also possible that the two sensor windings are relatively short and arranged in a "V" shape. If the two sensor windings are hypothetically extended in their radial longitudinal direction, these radial directions cross, rather than the two sensor windings themselves. It is a stricter condition that the two sensor windings themselves cross. Here, compared to the "V"-shaped arrangement, the sensor windings are longer and actually cross. The arrangement is "X"-shaped. Compared to the embodiment in which only the radial longitudinal directions of the sensor windings cross in the extension, in this embodiment, the sensor windings have a larger area in which voltage is induced and more voltage can be induced. In this case, the actual crossing of the sensor windings occurs, and no longer only the crossing occurs in the extension of the sensor windings.

[0069] Advantageously, in this embodiment, the two sensor windings are arranged symmetrically with respect to a center point of the energy transmission winding.

[0070] In an alternative preferred embodiment, the inductive charging device has at least four sensor windings, wherein two sensor windings are respectively arranged on opposite sides of the center of the energy transmission winding and all radial longitudinal directions extend 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.

[0071] Thus, four sensor windings are arranged, for example, in the shape of a cross around the center of the energy transmission winding, wherein the center of the energy transmission winding itself has no sensor windings.

[0072] Preferably, the four sensor windings can be arranged distributed around the center of the energy transmission winding at equal intervals in the radial direction and at approximately the same angle to each other. For example, the angle between the respective radial longitudinal direction of a sensor winding and the radial longitudinal direction of the respective adjacent sensor winding can always be 45°+ / -10°, preferably 45°.

[0073] On the one hand, this embodiment is advantageous over an embodiment with only two sensor windings, since in this arrangement the installation space can be used more efficiently and therefore more windings can be realized for each sensor winding. Overall, more voltage is thus induced. Compared to an embodiment with two crossed sensor windings, this embodiment also offers the advantage that the center of the energy transmission winding remains free of sensor windings and therefore stabilizing elements can be introduced in this area.

[0074] In this case, the four sensor windings can be interconnected with one another, preferably in series. Particularly preferably, two diagonally opposite sensor windings are each interconnected with one another in series.

[0075] In an advantageous variant, the locating signal winding is arranged at a distance from the center of the energy transmission winding of the first inductive charging device, in particular close to an edge of the energy transmission winding of the first inductive charging device or close to an edge of the first inductive charging device.

[0076] Particularly preferably, the locating signal winding is arranged during the locating process farther away from the further inductive charging device than the center of the energy transmission winding of the first inductive charging device.

[0077] In general, for a positioning method with the aid of the vehicle charging system according to the invention, not only is a maximum range provided, but also, in the case of a very small spacing between two inductive charging devices, in particular in the case of a very small spacing between two inductive charging devices in the driving plane, no usable signals are obtained from the sensor winding. Therefore, a further short-range positioning method can be used, for example, in areas in which two inductive charging devices are very close to each other. However, this further short-range positioning method has a very small range. In this regard, it is important that the minimum spacing is as small as possible, up to which the positioning method can be implemented with the aid of the inductive charging device according to the invention. This is achieved in that the positioning signal winding is arranged further away from the further inductive charging device than the center of the energy transmission winding of the first inductive charging device.

[0078] Particularly preferably, the positioning signal winding is formed by a conductor track which is applied to at least one printed circuit board, and

[0079] The first sensor winding and the second sensor winding are formed by conductor tracks which are applied on at least one printed circuit board.

[0080] The realization of the sensor winding by means of a conductor track on a printed circuit board makes it possible to significantly reduce the height of the sensor winding compared to conventional windings, for example based on high-frequency litz wires. Therefore, this shape of the sensor winding requires less structural space, especially in the dimension along the winding axis of the energy transmission winding, which dimension is most critical in terms of structural space. The corresponding printed circuit board can have any shape and / or size. Preferably, the corresponding printed circuit board has a shape extending in the direction of the winding portion, which has a width configured transversely to the longitudinal direction of the winding portion, which width is between 20 mm and 60 mm, especially from 30 mm to 50 mm, preferably 40 mm. As a result, multiple windings can be located on the printed circuit board, especially side by side on the printed circuit board. Preferably, the corresponding printed circuit board has a plurality of windings between 7 and 20, especially between 10 and 16, preferably 13. Compared with conventional windings with wound high-frequency litz wire conductors, the manufacturing method of the sensor winding based on the printed circuit board is simpler.

[0081] In a preferred embodiment, the first sensor winding and / or the second sensor winding and / or the locating signal winding is formed by an upper conductor track on the upper printed circuit board and by a lower conductor track on the lower printed circuit board.

[0082] The upper conductor track on the upper printed circuit board can be connected to the lower conductor track on the lower printed circuit board in such a way that a spiral winding is produced.

[0083] In this case, the upper conductor circuit can be arranged predominantly above one or more flux guiding elements and the lower conductor circuit can be arranged predominantly below one or more flux guiding elements.

[0084] The terms "above" and "below" or "upper" and "lower" refer to an arrangement of the inductive charging device which extends predominantly parallel to the substrate. If the charging device is arranged, for example, parallel to a wall, the terms should also be understood in the sense of "on one side of the flux guidance element" and "on the other side of the flux guidance element" without departing from the scope of the present invention.

[0085] Preferably, the upper conductor track is connected to the lower conductor track via through-hole metallization and / or surface-soldered plug strips and socket strips.

[0086] By using plug strips and socket strips, connections can be established during assembly of the inductive charging device without soldering conductor tracks. This offers significant advantages during production.

[0087] This is the case in particular in the variants of plug and socket strips with through-hole metallization.

[0088] However, when using surface mounted or surface soldered (SMD) plug strips and socket strips, the use of the plug strips and socket strips can also be accompanied by a soldering process, but this soldering process is significantly simpler than the soldering process without corresponding plug-in devices.

[0089] In an alternative preferred variant, the upper conductor circuit is connected to the lower conductor circuit via a flexible conductor circuit.

[0090] Here, the upper and lower circuit boards can also be designed as rigid circuit boards. The flexible circuit board ensures the connection via the vertical end faces and thus completes the winding of the coil around the at least one flux conducting element. Thus, a combination of rigid and flexible circuit boards is produced. This combination is also called a rigid-flexible composite circuit board (Starrflex-Leiterplatten). This is also a variant that allows simpler and more suitable production compared to on-site soldering.

[0091] The current flowing through the respective position signal winding preferably has an effective value of, in particular, between 130 mA and 390 mA, for example between 195 mA and 325 mA, preferably 260 mA.

[0092] The invention furthermore comprises an inductive charging device for a vehicle charging system according to the invention, wherein the inductive charging device comprises an energy transmission winding and at least one magnetic flux guiding element and at least one locating signal winding, wherein the locating signal winding is embodied as a solenoid having a winding axis in the longitudinal direction of the vehicle or in the longitudinal direction of the target vehicle, the magnetic flux guiding element being suitable for guiding a magnetic field during an energy transmission process to or from the inductive charging device, and the locating signal winding surrounds at least one of the at least one magnetic flux guiding element.

[0093] In a further preferred embodiment, a plurality of flux guidance elements are arranged in a plane radially around the center of the energy transmitting winding, wherein the gaps between the flux guidance elements also extend radially.

[0094] In terms of manufacturing technology, it is not possible or only very difficult to manufacture large flux guiding elements that cover the entire surface of the energy transmission coil or even extend beyond the entire surface. Therefore, it is usually necessary to place a plurality of smaller flux guiding elements side by side. Rectangular flux guiding elements can be used here. These rectangular flux guiding elements can be manufactured more simply. Then, there are always smaller gaps between the rectangular flux guiding elements. These gaps can negatively affect the guidance of the magnetic field. In the case of rectangular flux guiding elements, the gaps between the flux guiding elements always also extend partially perpendicular to the magnetic field lines. Therefore, it is advantageous that the gaps between the flux guiding elements also extend in the radial direction and thus affect the guidance of the magnetic field as little as possible.

[0095] Alternatively, the plurality of flux guidance elements can be embodied as at least approximately rectangular tile-like blocks having gaps between the flux guidance elements.

[0096] Further important features and advantages of the invention emerge from the dependent claims, the drawings and the associated description of the figures based on the drawings.

[0097] It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the respectively stated combination but also in other combinations or alone without departing from the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0098] Preferred exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein identical reference numerals refer to identical or similar components or components having the same function.

[0099] The accompanying drawings schematically show:

[0100] Figure 1 A greatly simplified schematic diagram of a vehicle with an inductive charging device above a stationary inductive charging device,

[0101] Figure 2 A schematic top view of an inductive charging device according to the present invention is shown,

[0102] Figure 3 A schematic top view of an alternative inductive charging device according to the invention is shown,

[0103] Figure 4 Schematic side views of two alternative inductive charging devices according to the invention are shown,

[0104] Figure 5 A schematic perspective view showing a positioning signal winding according to the present invention,

[0105] Figure 6A schematic diagram showing the direction in a winding,

[0106] Figure 7 A schematic diagram showing a vehicle charging system according to the present invention during a positioning process,

[0107] Figure 8 A top view of an inductive charging device according to the invention with a sensor winding is shown,

[0108] Fig. 9 A schematic top view showing an alternative inductive charging device according to the invention with a positioning signal winding DETAILED DESCRIPTION

[0109] Figure 1 The figure shows a mobile inductive charging device 1a, which is arranged on vehicle 2 with energy storage device 3 and is positioned above a stationary inductive charging device 1b. During operation, energy can be transferred from stationary inductive charging device 1b to mobile inductive charging device 1a, and the energy storage device of vehicle 3 can be charged thereby. Mobile inductive charging device 1a and stationary inductive charging device 1b together form vehicle charging system 8 or are part of vehicle charging system 8. In principle, it is also possible to operate vehicle charging system 8 bidirectionally. In this case, energy can be temporarily transferred from mobile inductive charging device 1a to stationary inductive charging device 1b. Alternatively, during operation, energy can be transferred from mobile inductive charging device 1a to stationary inductive charging device 1b. Figure 1 The stationary inductive charging device 1b arranged on a substrate in the embodiment can also be arranged sunken in the roadway (not shown here). In the case of a sunken arrangement, the inductive charging device 1b can be covered by a certain layer of the roadway or can be flush with the roadway surface.

[0110] Figure 2 The inductive charging device 1 according to the invention is shown, which has an energy transmission winding 4 and a plurality of flux conducting elements 5. The energy transmission winding 4 is designed as a flat coil 10. A positioning signal winding 41 is arranged around the flux conducting elements 5 and around the energy transmission winding 4. The positioning signal winding 41 is designed as a solenoid 42. Here, the positioning signal winding 41 is arranged centrally and extends through the center of the energy transmission winding 4.

[0111] Figure 3 An alternative inductive charging device 1 according to the invention is shown. Figure 2 Unlike the embodiment in , the locating signal winding 41 is arranged here only around the flux conducting element 5, but not around the energy transmission winding 4. In addition, the locating signal winding 41 does not extend through the center of the energy transmission winding 4, but is arranged close to the edge of the inductive charging device 1.

[0112] Figure 4Two different inductive charging devices 1 according to the invention are shown in side view. On the left side is shown an embodiment in which the locating signal winding 41 surrounds the energy transmission winding 4 and the flux conducting element 5. This means that the locating signal winding 41 is located in the vicinity of the energy transmission winding 4 and the flux conducting element 5. Figure 2 The right side shows an embodiment in which the positioning signal winding 41 surrounds the magnetic flux guiding element 5 but does not surround the energy transmission winding 4. That is, the positioning signal winding 41 is arranged in a manner that is wound around the energy transmission winding 4. Figure 3 The energy transmission winding 4 is arranged in the same way as in FIG.

[0113] Figure 5 A schematic perspective view of a locating signal winding 41 according to the invention is shown. Here, the locating signal winding is arranged around the flux conducting element 5. The locating signal winding 41 is implemented as a conductor track 38 on a circuit board 37. On the vertical short edges, the conductor tracks are connected via flexible elements as connecting elements 43.

[0114] Figure 6 It is schematically shown how a direction, in particular a radial longitudinal direction 11, is defined in a winding, in particular a sensor winding. Figure 6 In the example of , this involves a cylindrical coil with five windings. The direction along which the winding is wound is the winding axis 27. In this case, the coil has a rectangular, non-square cross section. The direction along the longer side of the rectangle is referred to here as the radial longitudinal direction 11. If the cross section is not rectangular, but elliptical, then the radial longitudinal direction 11 extends along the main axis of the ellipse.

[0115] Figure 7 a) schematically shows a vehicle 2 with a vehicle longitudinal direction 6 and a mobile inductive charging device 1a with a target vehicle longitudinal direction 6a during a positioning process above a stationary inductive charging device 1b. In the present case, the vehicle 2 is driving towards the stationary inductive charging device 1b, so that the target vehicle longitudinal direction 6a is identical to the vehicle longitudinal direction 6. The vehicle charging system comprises a mobile inductive charging device 1a and a stationary inductive charging device 1b. In addition to the energy transmission winding (not shown), a positioning signal winding 41 is also located in the mobile inductive charging device 1a. The positioning signal winding 41 has a winding axis 27 and a radial longitudinal direction 11. The conductor forming the positioning signal winding 41 extends mainly along the radial longitudinal direction 11. Therefore, during operation, the positioning signal winding 41 generates a magnetic field, wherein the orientation of the magnetic field lines is mostly parallel to the winding axis 27 and lies in one plane.

[0116] The magnetic field oriented in this way is particularly suitable for detecting azimuth deviations or angular deviations relative to the stationary inductive charging device 1b. In addition to the energy transmission winding (not shown), the stationary inductive charging device 1b also has two sensor windings 9a and 9b. The two sensor windings each have a radial longitudinal direction 11a and 11b, along which the conductors forming the sensor windings extend mainly. The two sensor windings are arranged at an angle of 45° relative to the target vehicle longitudinal direction 6a, and therefore relative to the vehicle longitudinal direction 6 in the target position, and are arranged symmetrically relative to the target vehicle longitudinal direction 6a. Therefore, the two sensor windings 9a and 9b or their radial longitudinal directions 11a and 11b are perpendicular to each other. This arrangement of the windings for positioning is particularly advantageous. The positioning signal winding 41 generates a relatively uniform magnetic field with magnetic field lines, which extend mainly in the driving plane and parallel to the longitudinal direction of the vehicle. In the sensor windings 9a and 9b, a voltage is induced by the magnetic field of the positioning signal winding 41. This voltage is proportional to the component of the magnetic field perpendicular to the respective radial longitudinal direction 11a, 11b of the sensor windings. If the vehicle is driven perpendicularly to the stationary inductive charger 1b as shown in the left figure, voltages of equal magnitude are induced in both sensor windings 9a and 9b.

[0117] Figure 7 b) shows the following embodiment: In this embodiment, the positioning signal winding 41 is arranged in the stationary inductive charging device 1b, and the sensor windings 9a and 9b are arranged in the mobile inductive charging device 1a. In other respects, the working principle of this embodiment is exactly the same. Here, the following situation is shown: In this case, the vehicle 2 does not drive perpendicularly to the stationary inductive charging device 1b, but deviates from it at an angle of approximately 45°. Therefore, the longitudinal direction of the vehicle 6 and the target longitudinal direction of the vehicle 6a are at an angle of 45° to each other. In this case, the positioning signal winding 41 generates a magnetic field perpendicular to the first sensor winding 9a. Here, the maximum voltage is induced. In addition, the magnetic field generated by the positioning signal winding 41 is approximately parallel to the second sensor winding 9b. Here, the minimum voltage or no voltage is induced.

[0118] Figure 8A top view of an inductive charging device 1 according to the invention is shown. 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 in a plane radially around the center 7 of the energy transmission winding 4. There are narrow gaps 27 between the flux guiding elements 5. The gaps also extend radially around the center 7, so that they extend approximately in the main direction of the magnetic field lines (three magnetic field lines 14 are symbolically indicated here), which occur when energy is transmitted into the flux guiding elements 5. The energy transmission winding 4, which is covered by the flux guiding elements 5 in the top view, is indicated by a dashed line. The energy transmission winding 4 is a flat coil 10 here. A first sensor winding 9, 9a is arranged around one of the flux guiding elements 5, and a second sensor winding 9, 9b is arranged around the other flux guiding element 5. In this case, the sensor winding is designed as a solenoid, also called a cylindrical coil. The first sensor winding 9a is arranged axially symmetrically with respect to the second sensor winding 9b about the vehicle longitudinal direction 6 (or the target vehicle longitudinal direction 6a). 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 6 of the vehicle 2 and the angle 13 between the second radial longitudinal direction 11b and the longitudinal direction of the vehicle are at least approximately the same size. The first radial longitudinal direction 11a and the second radial longitudinal direction 11b intersect or cross at least approximately at the center 7 of the energy transmission winding 4. The first radial longitudinal direction 11a and the second radial longitudinal direction 11b extend radially outward from the center 7 of the energy transmission winding 4.

[0119] During the charging process, vehicle 2 is positioned above stationary inductive charging device 1b and energy is transferred to inductive charging device 1a. In this case, the flux guidance element assumes the function of flux guidance. In the charging state, the field lines of the magnetic field extend approximately in the radial direction in the flux guidance element. Figure 3 , three magnetic field lines 14 are indicated symbolically. Since the first radial longitudinal direction 11a and the second radial longitudinal direction 11b are also oriented radially and therefore at least approximately parallel to the magnetic field lines 14, only relatively small voltages or even no voltages are induced in the first sensor winding 9a and the second sensor winding 9b. This is important, since otherwise damage to the sensor windings could easily occur in the case of high powers of energy transmission and therefore high magnetic flux densities. Therefore, additional expenditure is also required to prevent damage to this component.

[0120] Fig. 9An alternative preferred embodiment of the inductive charging device 1 is shown, which has a positioning signal winding 41. The inductive charging device 1 has an energy transmission winding 4 and a positioning signal winding 41. The positioning signal winding 41 is implemented as a solenoid 42. In addition, the inductive charging device 1 has a plurality of flux guiding elements 5. These flux guiding elements are arranged spaced apart from each other by gaps 27. The positioning signal winding 41 is arranged around the flux guiding element 5, but not around the energy transmission winding 4. The energy transmission winding 4 is implemented as a flat coil 10. The flux guiding element 5 is arranged on a mechanical support element 44. The positioning signal winding is arranged so that no support element 44 extends in this area and only the gap 27 extends in one direction between the flux guiding elements 5.

[0121] Reference numerals list

[0122] 1Inductive charging device

[0123] 1a Mobile inductive charging device

[0124] 1b Fixed induction charging device

[0125] 2 Vehicles

[0126] 3. Vehicle energy storage

[0127] 4 Energy transfer windings

[0128] 5. Magnetic flux guiding element

[0129] 6Longitudinal direction of vehicle

[0130] 6a Target vehicle longitudinal direction

[0131] 7 Center of the energy transfer winding

[0132] 8Vehicle Charging System

[0133] 9 sensor winding

[0134] 9a First sensor winding

[0135] 9b Second sensor winding

[0136] 10 Flat Coil

[0137] 11 Radial and longitudinal directions

[0138] 11a First radial longitudinal direction

[0139] 11b Second radial longitudinal direction

[0140] 12 First Angle

[0141] 13 Second Angle

[0142] 14 Magnetic Field Lines

[0143] 27 Gap between flux guiding elements

[0144] 28 Winding axis

[0145] 37 Circuit Board

[0146] 38 Conductor Circuit

[0147] 41 Positioning signal winding

[0148] 42 Solenoid

[0149] 43 Connecting elements between conductor circuits

[0150] 44 Support elements

Claims

1. An inductive charging device (1) for a vehicle charging system (8), the inductive charging device having an energy transmission winding (4) and at least one magnetic flux conducting element (5) and at least one positioning signal winding (41), wherein: - the positioning signal winding (41) is implemented as a solenoid (42) having a winding axis in the longitudinal direction of the vehicle or in the longitudinal direction of the target vehicle, and the flux guiding element (5) is suitable for guiding a magnetic field during an energy transfer process taking place between the further inductive charging device (1) and the energy transfer winding (4), and The positioning signal winding (41) surrounds at least one of the at least one flux guiding element (5) and surrounds the energy transmission winding (4).

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

3. The inductive charging device (1) according to claim 1 or claim 2, characterized in that: The positioning signal winding (41) is formed by a conductor track (38) which is applied to at least one printed circuit board (37), preferably to at least two printed circuit boards (37).

4. The inductive charging device (1) according to claim 1 or claim 2, characterized in that: The locating signal winding (41) is designed as a litz wire, in particular as a high-frequency litz wire, or as a metal wire.

5. The inductive charging device (1) according to any one of the preceding claims, characterized in that The positioning signal winding (41) at least approximately intersects with the winding axis of the energy transmission winding (4).

6. The inductive charging device (1) according to any one of claims 1 to 4, characterized in that: The locating signal winding (41) is arranged at a distance from the center of the energy transmission winding (4), in particular close to an edge of the energy transmission winding (4) of the inductive charging device (1) or close to an edge of the inductive charging device (1).

7. A vehicle charging system (8), comprising a first inductive charging device (1) and a further inductive charging device (1), wherein: - the first inductive charging device (1) has at least one energy transmission winding (4) and at least one magnetic flux conducting element (5) and at least one positioning signal winding (41), and the positioning signal winding (41) is implemented as a solenoid (42) having a winding axis in the longitudinal direction of the vehicle (6) or in the longitudinal direction of the target vehicle (6a), and - the further inductive charging device (1) has at least one energy transmission winding (4) and at least one magnetic flux guiding element (5) and a first sensor winding (9a) and a second sensor winding (9b), the first sensor winding having a first radial longitudinal direction (11a) and the second sensor winding having a second radial longitudinal direction (11b), and - The first radial longitudinal direction (11a) and the second radial longitudinal direction (11b) are arranged at an angle between 70° and 110° relative to each other, preferably perpendicular to each other, and are arranged at an angle between 35° and 55° relative to the vehicle longitudinal direction (6) or to the target vehicle longitudinal direction (6a), preferably at an angle of 45° relative to the vehicle longitudinal direction (6) or to the target vehicle longitudinal direction (6a).

8. The vehicle charging system (8) according to claim 7, characterized in that: The first inductive charging device (1) is a mobile inductive charging device (1a) which is arranged on and / or in the vehicle (2), and the further inductive charging device (1) is a stationary inductive charging device (1b), or The first inductive charging device (1) is a stationary inductive charging device (1b), and the further inductive charging device (1) is a mobile inductive charging device (1a), which is arranged on and / or in the vehicle (2).

9. The vehicle charging system (8) according to claim 7 or 8, characterized in that: The positioning signal winding (41) surrounds at least one magnetic flux guiding element of the at least one magnetic flux guiding element (5).

10. The vehicle charging system (8) according to any one of claims 7 to 9, characterized in that: - the positioning signal winding (41) at least approximately intersects the winding axis of the energy transmission winding (4) of the first inductive charging device, and The first radial longitudinal direction (11a) and the second radial longitudinal direction (11b) intersect at least approximately at the center (7) of the energy transmitting winding (4) of the further inductive charging device.

11. The vehicle charging system (8) according to any one of claims 7 to 9, characterized in that: The locating signal winding (41) is arranged spaced apart from the center of the energy transmission winding (4) of the first inductive charging device (1), in particular close to an edge of the energy transmission winding (4) of the first inductive charging device (1) or close to an edge of the first inductive charging device (1).

12. The vehicle charging system (8) according to claim 11, characterized in that The locating signal winding (41) is arranged during a locating process further away from the further inductive charging device (1) than the center of the energy transmission winding (4) of the first inductive charging device (1).

13. The vehicle charging system (8) according to any one of claims 7 to 12, characterized in that: - the positioning signal winding (41) is formed by a conductor track (38) which is applied to at least one printed circuit board (37), and The first sensor winding (9a) and the second sensor winding (9b) are formed by conductor tracks (38) which are applied to at least one printed circuit board (37).

14. An inductive charging device (1) for a vehicle charging system (8) according to any one of claims 7 to 13, the inductive charging device having an energy transmission winding (4) and at least one magnetic flux conducting element (5) and at least one positioning signal winding (41), wherein: - the positioning signal winding (41) is implemented as a solenoid (42) having a winding axis in the longitudinal direction of the vehicle or in the longitudinal direction of the target vehicle, and the flux guiding element (5) is suitable for guiding a magnetic field during an energy transfer process to or from the inductive charging device (1), and The positioning signal winding (41) surrounds at least one of the at least one flux guiding element (5).

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