Inductive charging device for a vehicle

Abstract

The invention relates to an inductive charging device for a vehicle charging system, comprising an energy-transmission winding and at least one flux-guiding element and at least one positioning signal winding. The positioning signal winding is in the form of a solenoid having a winding axis in the vehicle longitudinal direction or the target vehicle longitudinal direction, and the flux-guiding element is suitable for guiding a magnetic field during an energy-transmission process which takes place between a further inductive charging device and the energy-transmission winding. The positioning signal winding encloses at least one of the at least one flux-guiding element and the energy-transmission winding.

Description

[0001] Inductive charging device for a vehicle

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

[0003] DE 102018210726 A1 describes a positioning antenna used to position an inductive secondary unit relative to a primary unit. A 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 magnetic measuring field for positioning. The positioning antenna comprises several windings of a conductor and is implemented as a cylindrical coil made of ribbon cables. The positioning antenna exhibits advantageous directional properties.

[0004] In this case, the positioning antenna must always be laboriously positioned between the coil core and the charging coil. Furthermore, for the simple positioning antenna with advantageous directional effect, no correspondingly advantageous receiver is shown on the opposite side.

[0005] The present invention proposes an inductive charging device for a vehicle charging system comprising a power transmission winding, at least one flux guide element, and at least one positioning signal winding. The positioning signal winding is designed as a solenoid with a winding axis in the vehicle's longitudinal direction or the desired vehicle longitudinal direction, and the positioning signal winding surrounds at least one of the at least one flux guide element and the power transmission winding. During inductive charging, energy is transferred in the form of a magnetic field between two inductive charging devices, usually between a stationary charging device and a mobile inductive charging device.

[0006] The term "inductive charging device" therefore refers to only one of at least two components required for an inductive energy transfer process. During the inductive energy transfer process, a power transfer winding in an inductive charging device generates an alternating magnetic field. This alternating magnetic field induces a voltage in another power transfer winding of another inductive charging device. This additional inductive charging device thus serves as a counterpart for this specific energy transfer process. The energy is transmitted wirelessly and absorbed by inducing a voltage.

[0007] Inductive charging devices can be used for 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 with an electric or hybrid drive. This applies in particular to passenger cars, buses, and trucks.

[0008] 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.

[0009] An inductive charging device on and / or in the vehicle is therefore suitable for absorbing the magnetic field and supplying electrical energy from a vehicle's energy storage device, such as a battery or accumulator, to the vehicle. In principle, a vehicle charging system can also be used for bidirectional charging. In this case, the vehicle can also temporarily feed energy from the energy storage device into the power grid via the vehicle charging system.

[0010] An inductive charging device comprises a power transmission coil that can efficiently receive and / or emit a magnetic field from another power transmission coil during the power transmission process. Power levels of 3 kW to 500 kW can preferably be transmitted, particularly preferably 3 kW to 50 kW.

[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 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.

[0012] 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.

[0013] The energy transmission winding can be designed as a flat coil. 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 shape 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 single plane. A flat coil is 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 similar to a flat coil distributed over several levels, for example three levels, similar to a truncated pyramid.

[0015] A flux guide element is designed to guide a magnetic field in a predetermined manner. It has a high magnetic permeability with p 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 high permeability influences the magnetic field 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 ferrimagnetic 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.

[0016] A positioning signal winding can emit a positioning signal during a positioning process. For example, a positioning signal winding can generate an alternating magnetic field with a specific frequency due to an alternating voltage. In principle, an energy transmission winding can also emit a positioning signal, but it is advantageous, as proposed here, to use a separate positioning signal winding to generate a positioning signal. In particular, the positioning signal winding can generate magnetic fields that are more suitable for positioning and, in particular, enable a greater range with the same power. The energy transmission windings are designed to couple as well as possible with their corresponding counterparts. Therefore, they generally do not have a long range with regard to the transmission or reception of magnetic fields in the vehicle's longitudinal direction or.The desired vehicle longitudinal direction is shown. However, this is crucial for a positioning process.

[0017] During positioning, the maximum possible power or the maximum possible magnetic fields of the positioning signal are severely limited. They are significantly lower than is the case during an energy transfer process. During the positioning process, no vehicle is located on the stationary inductive charging device. Therefore, it is possible for a person, for example, to stand on the stationary inductive charging device. To ensure that the magnetic fields remain harmless to a person, they must not exceed flux densities of 27pT or 6.25pT, depending on the frequency range.

[0018] With a proposed positioning signal winding, it is possible to generate positioning signals that comply with the limit values ​​or reference values ​​and still enable a high range.

[0019] 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.

[0020] A stationary inductive charging device has a target vehicle longitudinal direction. This is the direction in which the vehicle's longitudinal direction should be after a successful positioning process. If the positioning signal winding is located in a mobile inductive charging device of a vehicle, the winding axis of the positioning signal winding is aligned in the vehicle's longitudinal direction. If the positioning signal winding is located in a stationary inductive charging device, the winding axis of the positioning signal winding is aligned in the target vehicle longitudinal direction.

[0021] In the proposed arrangement, the flux guide element guides a magnetic field for energy transfer during an energy transfer process and a magnetic field for positioning during a positioning process. Thus, the flux guide element performs a dual function, which is particularly advantageous because it allows for efficient use of material and installation space.

[0022] The arrangement of the positioning signal winding around at least one of the at least one flux guide element and around the energy transmission winding is advantageous because the positioning signal winding can be arranged around an otherwise pre-assembled inductive charging device. Furthermore, the positioning signal winding spans a larger area if it is arranged around at least one of the at least one flux guide element and around the energy transmission winding than, for example, if it is arranged around only one or more flux guide elements. Thus, with the same power, the local maximum values ​​of the flux density are further reduced or, to put it another way, a higher power can be used while adhering to the flux density reference values ​​or flux density limit values, thus achieving a greater range.

[0023] Particularly preferably, the positioning signal winding can be arranged across the entire width of the inductive charging device in order to cover the largest possible area and thus generate the most homogeneous magnetic field possible. An inductive charging device according to the invention is preferably a mobile inductive charging device arranged on and / or in a vehicle, or a stationary inductive charging device.

[0024] 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.

[0025] A stationary inductive charging device can preferably be located on, at, or in a floor. This can be an inductive charging device mounted on 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. However, a stationary inductive charging device can also be located on walls or similar structures.

[0026] It is also possible to use a stationary inductive charging device for a dynamic inductive charging process. With a dynamic inductive charging process, a vehicle's energy storage device 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.

[0027] 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.

[0028] Preferably, the positioning signal winding is formed by conductor tracks applied to at least one circuit board, preferably to at least two circuit boards. The windings of a positioning signal winding are implemented in the form of conductor tracks on circuit boards.

[0029] The conductor tracks can be made of copper, for example.

[0030] 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.

[0031] Implementing a positioning signal winding using conductive tracks on printed circuit boards makes it possible to significantly reduce the height of the positioning signal winding compared to conventional windings, such as those based on high-frequency stranded wires. This form of positioning signal 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.

[0032] Preferably, at least two circuit boards are used for a positioning signal winding, whereby one circuit board can be arranged on one side of a flux guide element, for example, above, and another circuit board can be arranged on another side of a flux guide element, for example, below. The conductor tracks on the two circuit boards are connected by appropriate flexible or non-flexible connections, thus forming a winding. The manufacturing process of a circuit board-based winding is also simpler compared to conventional windings with wound high-frequency stranded conductors.

[0033] In an alternative advantageous embodiment, the positioning signal winding is designed as a stranded wire, particularly as a high-frequency stranded wire or as a wire. A high-frequency stranded wire consists of several mutually insulated wires. This offers advantages because at high frequencies, the current flows primarily near the surface of a conductor, and the implementation with many individual conductors ensures the largest possible conductor surface area.

[0034] The term "wire" refers to the implementation as an insulated single wire, which is then wound in multiple turns. One advantage of implementing the positioning signal winding as a high-frequency stranded wire or as a wire is that it is a proven and simple manufacturing method.

[0035] For this embodiment, an additional mechanical support structure can be used to prevent the high-frequency strand or wire from slipping on the flux guide element.

[0036] Alternatively, it is possible to glue the high-frequency strand or wire to the at least one flux guide element to prevent slipping.

[0037] A spacer structure can also be used to ensure a defined distance between the individual turns of the positioning signal winding.

[0038] Preferably, the positioning signal winding at least approximately crosses the winding axis of the energy transmission winding.

[0039] Depending on the shape of the power transmission winding, it may not always be possible to clearly assign a winding axis directly. In this case, the winding axis is assumed to be located approximately at the geometric center of the power transmission winding.

[0040] Such an arrangement is advantageous because as little voltage as possible should be induced in the positioning signal winding during an energy transfer process, as the high power levels that occur during energy transfer could otherwise destroy or damage the positioning signal winding. The main direction of the magnetic flux in the at least one flux-guiding element is crucial for this. The main direction of the magnetic field lines at the respective location refers to the direction in which the magnetic field lines primarily extend within the flux-guiding element. Here, the magnetic field lines run primarily tangentially.Thus, an arrangement of the positioning signal winding approximately through the center of the energy transmission winding, i.e. crossing the winding axis of the energy transmission winding, is advantageous because in this case the conductors of the positioning signal winding run at least approximately parallel to the magnetic field lines and therefore only a very low voltage is induced.

[0041] In an alternative preferred embodiment, the positioning signal winding is arranged at a distance from the center of the energy transmission winding, in particular near an edge of the energy transmission winding of the inductive charging device or near an edge of the inductive charging device.

[0042] In this embodiment, the positioning signal winding is shifted to the position where the positioning signal winding intersects the winding axis of the energy transmission winding. The positioning signal winding is therefore not centrally located with respect to the energy transmission winding, nor centrally located in the inductive charging device. Compared to the center of the energy transmission winding, the positioning signal winding is located closer to or further away from the inductive charging device, which forms the counterpart. The positioning signal winding is spaced from the center of the energy transmission winding in the direction of an edge. "Edge" here simply means that the energy transmission winding or the inductive charging device ends there and makes no statement about the shape (e.g., whether rounded or not) of this edge.In particular, in a mobile inductive charging device, this is a front or rear edge, taking the vehicle's longitudinal direction into account, and in a stationary inductive charging device, it is a front or rear edge, taking the desired vehicle longitudinal direction into account. For example, the positioning signal winding can be arranged near an edge or, for example, halfway between the edge and the center of the energy transmission winding.

[0043] An arrangement at a distance from the center of the energy transmission winding has the advantage that a position for the positioning signal winding can be found here in which no further components, such as support elements or interruptions in the flux guide elements, make arrangement difficult.

[0044] Furthermore, an arrangement spaced apart from the center of the energy transmission winding is also advantageous for a positioning method. If the positioning signal winding is located closer to the inductive charging device that forms the counterpart than the center of the energy transmission winding, the range is increased. If the positioning signal winding is located further away from the inductive charging device that forms the counterpart than the center of the energy transmission winding, it is still possible to carry out a positioning method down to a smaller minimum distance between the two inductive charging devices. In general, there is not only a maximum range for a positioning method with a vehicle charging system according to the invention, but also that even at very small distances between the two inductive charging devices, no usable signal is received from the sensor windings.Therefore, for example, in areas where the two inductive charging devices are very close to each other, another close-range positioning method can be used. However, this method has a very short range. Therefore, it is important that the minimum distance up to which a positioning method is possible with an inductive charging device according to the invention is as small as possible. This is achieved by arranging the positioning signal winding farther away from the inductive charging device, which forms the counterpart, compared to the center of the energy transmission winding.

[0045] Furthermore, a vehicle charging system is proposed with 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 guide element and at least one positioning signal winding and the positioning signal winding is designed as a solenoid with a winding axis in the vehicle longitudinal direction or desired vehicle longitudinal direction and the further inductive charging device has at least one energy transmission winding and at least one flux guide element and a first sensor winding with a first radial longitudinal direction and a second sensor winding with a second radial longitudinal direction and the first radial longitudinal direction and the second radial longitudinal direction at an angle between 70° and 110° to each other,preferably perpendicular to each other and at an angle between 35° and 55° to the vehicle longitudinal direction or to the desired vehicle longitudinal direction, preferably at a 45° angle to the vehicle longitudinal direction or to the desired vehicle longitudinal direction.

[0046] Such a design and arrangement of the positioning signal winding and the sensor winding is advantageous for both a positioning process and a power transmission process. The design of the positioning signal winding as a solenoid with a winding axis in the vehicle's longitudinal direction or in the desired vehicle's longitudinal direction generates a magnetic field with a main direction of the magnetic field lines in the vehicle's longitudinal direction or in the desired vehicle's longitudinal direction. This has the advantage that this design enables a significantly greater range for positioning than would be the case with a positioning signal generated by a power transmission winding with the same power or the same magnetic field strength. Furthermore, such an orientation of the magnetic field is also particularly well suited to enabling the simplest possible detection of a positional deviation or an angular deviation in the sensor windings.

[0047] Particularly preferably, the positioning signal winding is designed such that it has a particularly large extension in the travel plane and perpendicular to the vehicle longitudinal direction or to the desired vehicle longitudinal direction.

[0048] For example, the positioning signal winding can extend across the entire width of an inductive charging device. This creates a largely homogeneous magnetic field with a primary direction of magnetic flux in the vehicle's longitudinal direction or the desired vehicle's longitudinal direction.

[0049] A proposed arrangement of the sensor windings is also advantageous for an optimized positioning process. If the sensor windings are arranged symmetrically to the vehicle's longitudinal direction or to the desired vehicle longitudinal direction, an angular deviation relative to a homogeneous 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.

[0050] During an energy transfer process, as little voltage as possible should be induced in both the positioning signal winding and the energy transfer winding, since the high power or field strengths during energy transfer could otherwise lead to destruction of the corresponding windings.

[0051] A positioning signal winding according to the invention and sensor signal windings according to the invention can advantageously be arranged in the respective inductive charging device such that the conductors forming these windings run primarily parallel to the main direction of the magnetic flux during energy transfer at the respective location. This ensures that the lowest possible voltage is induced in the respective windings during energy transfer. In particular, the orientation of the magnetic flux in the respective flux guide elements of the inductive charging devices is crucial for this. This can preferably run radially outward from the center of the respective energy transfer winding.

[0052] It is preferred that the first inductive charging device is a mobile inductive charging device which is arranged on and / or in a vehicle, and the further inductive charging device is a stationary inductive charging device, or that the first inductive charging device is a stationary inductive charging device and the further inductive charging device is a mobile inductive charging device which is arranged on and / or in a vehicle.

[0053] Advantageously, the positioning signal winding encloses at least one of the at least one flux guiding elements.

[0054] In the proposed arrangement, the flux guide element guides a magnetic field for energy transfer during an energy transfer process and a magnetic field for positioning during a positioning process. Thus, the flux guide element performs a dual function.

[0055] Preferably, the positioning signal winding at least approximately crosses 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 in the center of the energy transmission winding of the further inductive charging device.

[0056] This arrangement ensures that the conductors forming the positioning signal winding and the sensor windings run at least approximately parallel to the magnetic field lines that develop at the respective location during energy transfer. This ensures that the lowest possible voltage is induced in the corresponding windings during energy transfer, preventing them from being destroyed by the high power generated during energy transfer.

[0057] The center of the energy transmission winding refers here to the area a few centimeters around the geometric center of the energy transmission winding in the plane perpendicular to the winding axis of the energy transmission winding.

[0058] A corresponding arrangement of the sensor windings 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.

[0059] 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.

[0060] 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.

[0061] It is advantageous if, in this embodiment, the two sensor windings are arranged point-symmetrically to the center of the energy transmission winding.

[0062] 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.

[0063] 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.

[0064] 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°.

[0065] 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.

[0066] The four sensor windings can be interconnected, preferably in series. Particularly preferred is the two diagonally opposite sensor windings being interconnected in series.

[0067] In an advantageous variant, the positioning signal winding is spaced from the center of the energy transmission winding of the first inductive

[0068] Charging device is arranged in particular near an edge of the energy transmission winding of the first inductive charging device or near an edge of the first inductive charging device.

[0069] Particularly preferably, the positioning signal winding is arranged further away from the further inductive charging device during a positioning process than the center of the energy transmission winding of the first inductive charging device.

[0070] In general, there is not only a maximum range for a positioning method using a vehicle charging system according to the invention, but also that even at very small distances, particularly at very small distances in the travel plane, no usable signal is received from the sensor windings between the two inductive charging devices. Therefore, for example, in the area in which the two inductive charging devices are very close to each other, another short-range positioning method can be used. However, this has a very short range. In this respect, it is important that the minimum distance up to which a positioning method is possible with an inductive charging device according to the invention is as small as possible.This is achieved by arranging the positioning signal winding further away from the further inductive charging device compared to the center of the energy transmission winding of the first inductive charging device.

[0071] Particularly preferably, the positioning signal winding is formed by conductor tracks applied to at least one printed circuit board, and the first sensor winding and the second sensor winding are formed by conductor tracks applied to at least one printed circuit board. 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, for example, those based on high-frequency stranded wires. This form of sensor winding therefore requires less installation space, particularly in the dimension along the winding axis of the energy transmission winding, which is the most critical in terms of installation space. The respective printed 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 between 40 mm. This allows multiple windings, in particular adjacent to one another, to be located thereon. Preferably, the respective circuit board has a plurality of windings between 7 and 20, in particular between 10 and 16, preferably 13. The manufacturing process for a circuit board-based sensor winding is also simpler compared to conventional sensor windings with wound high-frequency stranded conductors.

[0072] In a preferred embodiment, the first sensor winding and / or the second sensor winding and / or the positioning signal winding consist of upper conductive tracks on an upper circuit board and of lower conductive tracks on a lower circuit board.

[0073] 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.

[0074] The upper conductor track can be arranged predominantly above one or more flux guiding elements and the lower conductor track can be arranged predominantly below one or more flux guiding elements.

[0075] The terms "above" and "below" or "upper" and "lower" refer to the arrangement of an inductive charging device that extends primarily parallel to the ground. If, for example, a charging device is arranged parallel to a wall, the terms continue to be understood as "on one side of the flux guide elements" and "on the other side of the flux guide elements," without departing from the scope of the invention.

[0076] Preferably, the upper conductor tracks are connected to the lower conductor tracks via through-plated and / or surface-soldered plug and socket strips.

[0077] 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.

[0078] This is especially the case with the version with the through-hole plug and socket connectors.

[0079] However, the use of surface-mounted or surface-soldered (SMD) plug and socket strips may also involve a soldering process, which is, however, significantly simpler than a soldering process without the corresponding connectors. In an alternative preferred variant, the upper conductor tracks are connected to the lower conductor tracks via flexible printed circuit boards.

[0080] 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 at least one flux guide 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.

[0081] The electrical current flowing through the respective positioning signal winding, preferably the effective value, is in particular between 130 mA and 390 mA, for example between 195 mA and 325 mA, preferably 260 mA.

[0082] The invention further includes an inductive charging device for a vehicle charging system according to the invention, wherein the inductive charging device 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 designed as a solenoid with a winding axis in the vehicle longitudinal direction or desired vehicle longitudinal direction and the flux guiding element is suitable for guiding a magnetic field to or from the inductive charging device during an energy transmission process, and the positioning signal winding encloses at least one of the at least one flux guiding elements.

[0083] In a further preferred embodiment, a plurality of flux guiding elements are arranged radially around the center of the energy transmission winding, with gaps between the flux guiding elements also running radially. From a manufacturing perspective, it is impossible or very difficult to produce a large flux guiding element that covers the entire surface of the energy transmission coil or even projects beyond it. Therefore, a plurality of smaller flux guiding elements usually have to be placed next to one another. In this case, it is possible to use rectangular flux guiding elements. These are easier to manufacture. Smaller gaps are then always present between the flux guiding elements. These can negatively influence the guidance of the magnetic field. With rectangular flux guiding elements, the gaps between the flux guiding elements will always run partially perpendicular to the magnetic field lines.It is therefore advantageous if the gaps between the flux guiding elements also run radially and thus influence the guidance of the magnetic field as little as possible.

[0084] Alternatively, several flow guidance elements can be designed as at least approximately rectangular tiles with gaps between the flow guidance elements.

[0085] 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.

[0086] 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.

[0087] Preferred embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description, wherein like reference numerals refer to like or similar or functionally identical components. It shows, in each case schematically

[0088] Fig. 1 a highly simplified representation of a vehicle with an inductive charging device above a stationary inductive charging device

[0089] Fig. 2 is a schematic plan view of an inductive charging device according to the invention

[0090] Fig. 3 is a schematic plan view of an alternative inductive charging device according to the invention

[0091] Fig. 4 schematic side views of two alternative inductive charging devices according to the invention

[0092] Fig. 5 schematic perspective view of a positioning signal winding according to the invention

[0093] Fig. 6 a schematic representation of the directions in a winding

[0094] Fig. 7 is a schematic representation of an inventive

[0095] Vehicle charging system during the positioning process

[0096] Fig. 8 Top view of an inductive charging device according to the invention with sensor windings

[0097] Fig. 9 is a plan view of an alternative inductive charging device according to the invention with positioning signal windings

[0098] 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, thereby charging the energy storage device of the vehicle 3.

[0099] 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.

[0100] Fig. 2 shows an inductive charging device 1 according to the invention with an energy transmission winding 4 and a plurality of flux guide elements 5. The energy transmission winding 4 is designed as a flat coil 10. A positioning signal winding 41 is arranged around the flux guide elements 5 and around the energy transmission winding 4. The positioning signal winding 41 is designed as a solenoid 42. The positioning signal winding 41 is arranged centrally and runs across the center of the energy transmission winding 4.

[0101] Fig. 3 shows an alternative inductive charging device 1 according to the invention. In contrast to the embodiment in Fig. 2, the positioning signal winding 41 is arranged only around the flux guide elements 5 but not around the energy transmission winding 4. Furthermore, the positioning signal winding 41 does not run across the center of the energy transmission winding 4, but is arranged near an edge of the inductive charging device 1.

[0102] Fig. 4 shows two different inductive charging devices 1 according to the invention in a side view. The left shows the embodiment in which a positioning signal winding 41 surrounds the energy transmission winding 4 and the flux-guiding elements 5. The positioning signal winding 41 is thus wound around the energy transmission winding 4, as in Fig. 2. The right shows the embodiment in which a positioning signal winding 41 surrounds the flux-guiding elements 5 but not the energy transmission winding 4. The positioning signal winding 41 is thus not wound around the energy transmission winding 4, as in Fig. 3.

[0103] Fig. 5 shows a schematic perspective view of a positioning signal winding 41 according to the invention. Here, it is arranged around a flux guide element 5. The positioning signal winding 41 is implemented as conductor tracks 38 on printed circuit boards 37. At the vertical short edges, the conductor tracks are connected via flexible elements as connecting elements 43.

[0104] Fig. 6 schematically shows how the directions, in particular the radial longitudinal direction 11, are defined in a winding, particularly in a sensor winding. The example in Fig. 6 shows a cylindrical coil with five turns. The direction along which the winding was wound is the winding axis 27. The coil here has a rectangular, not 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, the radial longitudinal direction 11 runs along the main axis of the ellipse.

[0105] Fig. 7 a) schematically shows a vehicle 2 with a vehicle longitudinal direction 6 with a mobile inductive charging device 1a during a positioning process above a stationary inductive charging device 1b with a target vehicle longitudinal direction 6a. In the present case, the vehicle 2 is driving towards the stationary inductive charging device 1b and the target vehicle longitudinal direction 6a is thus the same as the vehicle longitudinal direction 6. The vehicle charging system includes the mobile inductive charging device 1a and the stationary inductive charging device 1b. In addition to the energy transmission winding (not shown), the mobile inductive charging device 1a also contains a positioning signal winding 41. The positioning signal winding 41 has a winding axis 27 and a radial longitudinal direction 11. The conductors which form the positioning signal winding 41 extend mainly along the radial longitudinal direction 11.During operation, the positioning signal winding 41 thus generates a magnetic field, the orientation of the magnetic field lines being largely parallel to the winding axis 27 in a plane.

[0106] A magnetic field aligned in this way is particularly suitable for detecting a positional deviation or an angular deviation with respect to the stationary inductive charging device 1b. In addition to the energy transmission winding (not shown), the stationary inductive charging device 1b has two sensor windings 9a and 9b. Both sensor windings each have a radial longitudinal direction 11a and 11b, in which the conductors forming the sensor windings mainly extend. Both sensor windings are arranged at an angle of 45° to the desired vehicle longitudinal direction 6a and thus to the vehicle longitudinal direction 6 in the target position and symmetrical to the desired vehicle longitudinal direction 6a. The two sensor windings 9a and 9b or their radial longitudinal directions 11a and 11b are thus perpendicular to one another. This arrangement of the windings is particularly advantageous for positioning.The positioning signal winding 41 generates a fairly homogeneous magnetic field with magnetic field lines that extend primarily in the travel plane and parallel to the vehicle's longitudinal direction. A voltage is induced in the sensor windings 9a and 9b by the magnetic field of the positioning signal winding 41. This voltage is proportional to the component of the magnetic field that is perpendicular to the respective radial longitudinal direction 11a, 11b of the sensor winding. If the vehicle travels exactly perpendicularly toward the stationary inductive charging device 1b, as shown in the left-hand sketch, an equal voltage is induced in both sensor windings 9a and 9b.

[0107] Fig. 7b) shows an embodiment in which 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. The functioning of this embodiment is otherwise exactly the same. Shown here is a case in which the vehicle 2 does not drive perpendicularly towards the stationary inductive charging device 1b, but deviates from it at an angle of approximately 45°. The vehicle's longitudinal direction 6 and the desired vehicle longitudinal direction 6a are therefore at an angle of 45° to one another. In this case, the positioning signal winding 41 generates a magnetic field which is perpendicular to the first sensor winding 9a. Here, a maximum voltage is induced. The magnetic field generated by the positioning signal winding 41 is also approximately parallel to the second sensor winding 9b. Here, a minimal voltage or no voltage is induced.

[0108] Fig. 8 shows a top 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 embodiment, eight flux guide elements 5 are shown, which are arranged radially around the center 7 of the energy transmission winding 4 in the plane. Narrow gaps are formed between the flux guide elements 5.

[0109] Reference source could not be found. The gaps also run radially around the center 7, thus the gaps run approximately in the main direction of the magnetic field lines (three magnetic field lines 14 symbolically indicated here) that arise during energy transfer in the flux guide elements 5. The energy transfer winding 4, which is concealed by the flux guide elements 5 in the plan view, is indicated by dashed lines. The energy transfer winding 4 is a flat coil 10 here. A first sensor winding 9, 9a is arranged around one of the flux guide elements 5 and a second sensor winding 9, 9b is arranged around another flux guide element 5. The sensor windings 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 vehicle longitudinal direction 6 (or the desired 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 11b between the first radial longitudinal direction 11a and the longitudinal direction 6 of the vehicle 2 is at least approximately equal to the angle 12 between the second radial longitudinal direction 11b and the longitudinal direction of the vehicle. The first radial longitudinal direction 11a and the second radial longitudinal direction 11b intersect or cross at least approximately in 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.

[0110] 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. Three magnetic field lines 14 are symbolically indicated in Fig. 3. 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 because the high power levels of the energy transfer and thus the high flux densities could otherwise easily lead to the sensor windings being destroyed.Therefore, no additional effort is necessary to prevent the destruction of the arrangement.

[0111] Fig. 9 shows an alternative preferred embodiment of an inductive charging device 1 with 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 designed as a solenoid 42. The inductive charging device 1 further has a plurality of flux guiding elements 5. These are arranged at a distance from one another by gaps 27. The positioning signal winding 41 is arranged around the flux guiding elements 5, but not around the energy transmission winding 4. The energy transmission winding 4 is designed as a flat coil 10. The flux guiding elements 5 are arranged on mechanical support elements 44. The positioning signal winding 41 is arranged such that no support elements 44 run in this area and only gaps 27 run in one direction between the flux guiding elements 5.

[0112] Reference symbol

[0113] 1 inductive charging device

[0114] 1a mobile inductive charging device

[0115] 1 b stationary inductive charging device

[0116] 2 vehicles

[0117] 3 Vehicle energy storage

[0118] 4 Energy transmission winding

[0119] 5 Flow guide element

[0120] 6 Vehicle longitudinal direction

[0121] 6a Target vehicle longitudinal direction

[0122] 7 Center of the energy transmission winding

[0123] 8 Vehicle charging system

[0124] 9 Sensor winding

[0125] 9a first sensor winding

[0126] 9b second sensor winding

[0127] 10 flat coil

[0128] 11 radial longitudinal direction

[0129] 11 a first radial longitudinal direction

[0130] 11 b second radial longitudinal direction

[0131] 12 first angle

[0132] 13 second angle

[0133] 14 magnetic field lines

[0134] 27 Gap between flow guide elements

[0135] 28 Winding axis

[0136] 37 circuit board

[0137] 38 conductor tracks

[0138] 41 Positioning signal winding

[0139] 42 Solenoid 43 Connecting element between conductor tracks

[0140] 44 Support element

Claims

Claims Inductive charging device (1 ) for a vehicle charging system (8) with a power transmission winding (4) and at least one flux guide element (5) and at least one positioning signal winding (41 ), wherein - the positioning signal winding (41 ) is designed as a solenoid (42) with a winding axis in the longitudinal direction of the vehicle or the intended longitudinal direction of the vehicle and - the flux guiding element (5) is suitable to guide a magnetic field during an energy transfer process which takes place between another 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 guide elements (5) and surrounds the energy transfer winding (4). 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 a vehicle (2) or that - the inductive charging device (1) is a stationary inductive charging device (1b). Inductive charging device (1) according to claim 1 or claim 2, characterized in that the positioning signal winding (41) is formed by conductor tracks (38) which are applied to at least one printed circuit board (27), preferably to at least two printed circuit boards (27). Inductive charging device (1) according to claim 1 or claim 2, characterized in that the positioning signal winding (41) is configured as a stranded wire, in particular as a high-frequency stranded wire or as a solid wire. Inductive charging device (1) according to any one of the preceding claims, characterized in that the positioning signal winding (41) crosses at least approximately the winding axis of the energy transfer winding (4). Inductive charging device (1) according to any one of claims 1-4, characterized in that the positioning signal winding (41) is arranged at a distance from the center of the energy transfer winding (4), in particular near an edge of the energy transfer winding (4) of the inductive charging device (1). Vehicle charging system (8) with 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 transfer winding (4) and at least one flux guide element (5) and at least one positioning signal winding (41 ) and - the positioning signal winding (41 ) is designed as a solenoid (42) with a winding axis in the longitudinal direction of the vehicle (6) or the desired longitudinal direction of the vehicle (6a) and - the further inductive charging device (1) at least one energy transfer winding (4) and at least one flux guide element (5) and a first sensor winding (9a) with a first radial longitudinal direction (11a) and a 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) are arranged at an angle between 70° and 110° to each other, preferably perpendicular to each other and at an angle between 35° and 55° to the vehicle longitudinal direction (6) or to the intended vehicle longitudinal direction (6a), preferably at a 45° angle to the vehicle longitudinal direction (6) or to the intended vehicle longitudinal direction (6a). Vehicle loading system (8) according to claim 7, characterized in that, - that the first inductive charging device (1 ) is a mobile inductive charging device (1a) which is arranged on and / or in a vehicle (2) and the further inductive charging device (1 ) is a stationary inductive charging device (1 b) or - that 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 a vehicle (2). Vehicle charging system (8) according to claim 7 or claim 8, characterized in that the positioning signal winding (41) surrounds at least one of the at least one flux guide elements (5). Vehicle charging system (8) according to one of claims 7-9, characterized in that - the positioning signal winding (41) crosses at least approximately the winding axis of the energy transfer 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 transfer winding (4) of the further inductive charging device. Vehicle charging system (8) according to one of claims 7-9, characterized in that the positioning signal winding (41) is arranged at a distance from the center of the energy transfer winding (4) of the first inductive charging device (1), in particular near an edge of the energy transfer winding (4) of the first inductive charging device (1). Vehicle charging system (8) according to claim 11, characterized in that the positioning signal winding (41) is arranged further away from the further inductive charging device (1) during a positioning process than the center of the energy transfer winding (4) of the first inductive charging device (1).Vehicle charging system (8) according to one of claims 7-12, characterized in that. - the positioning signal winding (41 ) is formed by conductor tracks (38) which are 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 circuit board (37). Inductive charging device (1 ) for a vehicle charging system (8) according to one of claims 7-13 with an energy transfer winding (4) and at least one flux guide element (5) and at least one positioning signal winding (41) , wherein - the positioning signal winding (41 ) is designed as a solenoid (42) with a winding axis in the longitudinal direction of the vehicle or the intended longitudinal direction of the vehicle and - the flux guiding element (5) is suitable for guiding a magnetic field to or from the inductive charging device (1) during an energy transfer process and - the positioning signal winding (41) encloses at least one of the at least one flow guide elements (5).

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