Method for identifying relative position between stationary and mobile inductive charging devices

Abstract

The present invention relates to a method for identifying the relative positions of a stationary inductive charging device (2, 2a) and a mobile inductive charging device (2, 2b) interacting with each other during a charging operation for inductive energy transfer. Accurate and robust identification of the relative positions of the energy coils (3) of the inductive charging device (2) with respect to one another is achieved by generating at least two fixed positioning fields (60) relative to one of the energy coils (3), receiving these positioning fields (60) at a fixed location with respect to the other energy coil (3) and determining a ratio (62) between the positioning fields (60), and if the determined ratio (62) coincides with a pre-set ratio range (63), an overlap of the two energy coils (3) is identified. The invention further relates to a computer program product for carrying out the method, a system (1) so operated, and a mobile application (100) comprising a mobile inductive charging device (2, 2a) of such a system (1). Furthermore, the invention relates to a stationary inductive charging device (2, 2a) of such a system (1).

Description

[Technical field]

[0001] The present invention relates to a method for identifying the relative positions of a stationary inductive charging device and a mobile inductive charging device which interact with each other during a charging operation for inductive energy transfer. The present invention further relates to a computer program product for carrying out the method, a system comprising a stationary inductive charging device and a mobile inductive charging device operated according to the method, and a mobile application, in particular a motor vehicle, comprising a mobile inductive charging device of such a system, as well as a stationary inductive charging device of such a system.

[0002] A system for inductive energy transfer typically comprises a stationary inductive charging device as well as a mobile inductive charging device. During a charging operation, the energy coil of one of these inductive charging devices functions as a primary coil, and the energy coil of the other inductive charging device functions as a secondary coil. This type of system is typically used for inductive energy transfer to a mobile application, for example to a car, in which case the mobile application comprises a mobile inductive charging device. In the mobile application, the energy coil of the mobile inductive charging device is customarily a secondary coil during a charging operation. For inductive energy transfer, the primary coil generates an alternating magnetic field, which induces a voltage in the secondary coil. To enable inductive energy transfer and to increase the efficiency of inductive energy transfer, the primary coil and the secondary coil, and thus the energy coil of the inductive charging device, must be positioned in a relative correspondence to each other.

[0003] In EP 2727759 a transmitter and receiver are used to identify the relative position of a mobile inductive charging device mounted in a vehicle.

[0004] DE 10 2012205 283 A1 proposes using an even number of detector coil elements which are counter-wound in pairs to form a detector pair.

[0005] EP 3347230 proposes using a transmitting unit in a mobile inductive charging device, which transmits a transmission signal of a preset frequency during operation, which is received by means of a receiving unit and a signal component of the transmission signal is determined, whereby the relative position is determined depending on the determined signal component.

[0006] DE 102017215932 describes a method for determining the position of a vehicle on a ground. The vehicle is equipped with a mobile inductive charging device. By energizing an energy coil of the mobile inductive charging device, at least one magnetic structure arranged in or on the ground over which the vehicle has traveled is magnetized. The structures are stored in a digital map together with the position information of the respective structures, and the position of the vehicle is then determined on the basis of the magnetized structures.

[0007] The problem addressed by the present invention is to provide improved or at least alternative embodiments for a method for identifying the relative position of a stationary inductive charging device and a mobile inductive charging device, for a computer program product for carrying out the method, for a system comprising a stationary inductive charging device and a mobile inductive charging device operated according to the method, for a mobile application of such a system with a mobile inductive charging device, and for a stationary inductive charging device of such a system, in particular to obviate the drawbacks of the prior art. In particular, the problem addressed by the present invention is to provide improved or at least alternative embodiments for the method, computer program product, system, and mobile application, as well as for the stationary inductive charging device, which are distinguished by increased accuracy and / or increased robustness of the identification of the relative positioning of the energy coils of the system.

[0008] This problem is solved according to the invention by the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims.

[0009] The invention is therefore based on the general consideration that, for one of the energy coils, at least two mutually distinguishable and fixed fields are generated, which are received at a fixed position relative to the other energy coil, in order to identify the relative position between the two energy coils, and the relative position of the two energy coils is identified based on the ratio between the received fields. Based on the fixed arrangement of the fields relative to one energy coil and the reception of the fields at a fixed location relative to the other energy coil, this ratio varies depending on the relative position of the energy coils. The energy coils are therefore arranged, for example, in a superimposed manner at a preset ratio between the fields. In this way, the relative positions of the energy coils and in particular the superimposed arrangement of the energy coils relative to one another can be determined in a simple and effective manner. Since the field ratio is used for identifying the relative positions of the energy coils relative to one another, a more reliable and simpler calculation of the relative positions is provided, in particular compared to the calculation of the absolute values ​​of the fields or the calculation of the propagation time difference of at least one field, which is known from the prior art. This is because, inter alia, the ratio of the received fields does not change at all or only changes very little with varying distances in the height direction, so that, for example, a mobile inductive charging device may be installed or positioned at different heights in the associated application and / or a stationary inductive charging device may be installed or positioned at different heights or depths, and the relative positions of the energy coils to one another are nevertheless identifiable without further calibration.

[0010] The use of ratios for identifying the relative positions of the energy coils to one another, as explained, has the advantage that it is possible to dispense with repeated calibration of the inductive charging devices which inductively transfer energy to one another, i.e. at least one ratio can be preset in advance and, when such ratio is determined from the received field, it is identified that a corresponding relative position of the energy coils to one another exists. In this way, it is possible, in particular, to transmit said preset ratios from the field-generating inductive charging device once to the receiving inductive charging device, preferably before positioning is started, in order to determine the relative positions of the energy coils to one another. Alternatively, preferably, these ratios are preset in a fixed manner, so that they are stored in the receiving inductive charging device and thus no transmission to the receiving inductive charging device is necessary. This makes it possible, in particular, to determine the relative positions between the energy coils of different stationary inductive charging devices and the energy coils of various mobile inductive charging devices in a simple and robust manner without a prior calibration.

[0011] According to the considerations of the invention, the method is used for identifying the relative position of a stationary inductive charging device and a mobile inductive charging device, the stationary inductive charging device having a stationary energy coil and the mobile inductive charging device having a mobile energy coil, the energy coils being spaced apart from each other in the height direction during a charging operation. During a charging operation, one of the energy coils generates an alternating magnetic field, which induces a voltage for energy transmission in the other energy coil, whereby the energy coils are spaced apart from each other in the height direction during a charging operation. In order to identify the relative position of the energy coils to each other, at least two fields are generated in one of the inductive charging devices, which fields are also referred to as positioning fields in the following. The positioning fields are generated such that they are distinguishable from each other and that the energy coils of the associated inductive charging device, i.e. the inductive charging device generating the positioning field, are fixedly positioned relative to the positioning field. Furthermore, the positioning fields are generated such that the energy coil is at least partially located within a virtual frame volume that is defined by at least two intensity maxima of at least two of these positioning fields and extends in the height direction. These positioning fields are received at at least one position that is fixed with respect to the energy coil of the other inductive charging device. A ratio range is pre-predefined for the local ratio between at least two of the near fields. The pre-predefined ratio range is such that the energy coil of the inductive charging device that receives the positioning field is located within the frame volume. That is to say, a ratio range of at least two of the received positioning fields is pre-predefined such that the energy coil of the inductive charging device that receives the positioning field is located within the frame volume. In order to identify the relative positions of the energy coils to one another, a ratio between at least two of the received positioning fields is determined. Here, it is identified that the energy coil is located within the frame volume and overlaps laterally with respect to the height direction if at least one ratio of the at least one determined ratio is located within the corresponding pre-predefined ratio range.

[0012] The determination of the relative positions of the energy coils with respect to one another is preferably effected by comparing at least one determined ratio with an associated ratio range.

[0013] At least one ratio range is preferably stored, which simplifies the implementation of the method.

[0014] Expediently, at least two of the positioning fields, in particular all of the positioning fields, overlap within the frame volume.

[0015] The positioning can include the mutual proximity of the energy coils and the mutual accurate positioning of the energy coils, which is also referred to below as near-field positioning. The positioning device described herein is expediently used here for near-field positioning. Near-field positioning is advantageously used here when the energy coils have a distance of less than 1.0 m, preferably less than 0.5 m, from each other in order to accurately position the energy coils from each other. At least one near field can be used to bring the energy coils close to each other.

[0016] Each energy coil preferably has at least one winding. In the context of the present invention, the extent of the energy coil is understood here to mean in particular the entire area that is covered by at least one winding, i.e. in a flat coil, the central area, where no windings may be present, also belongs to the energy coil.

[0017] These positioning fields may be generated in any manner within the inductive charging device that generates the positioning fields.

[0018] Advantageously, at least one of these positioning fields, and preferably each positioning field, is a magnetic and / or electromagnetic field.

[0019] Preferably, at least one of these positioning fields, preferably each of these positioning fields, is a magnetic field. That is to say, at least one of these positioning fields, preferably each of these positioning fields, is generated as a magnetic positioning field. A magnetic positioning field has the advantage that it is simply and reliably received by the receiver in comparison with an electromagnetic positioning field. Furthermore, in this way it is possible to dispense with calibrations with execution time differences, as is required, for example, for normal electromagnetic and / or acoustic fields. Thus, by using a magnetic positioning field, a simple and robust calculation of the ratio and thus of the relative position of the energy coils to one another is performed. In particular, the omission of the calibrations performed during each positioning also leads to the possibility of performing positioning between different inductive charging devices. In other words, the use of a magnetic positioning field makes it possible to realize positioning with different inductive charging devices in a simple manner.

[0020] Preferably, the main axis of each positioning field extends along the height direction, i.e. each positioning field extends at least primarily in or along the height direction and is therefore only receivable transversely to the height direction locally in the area of ​​the associated transmitting coil and energy coil, i.e. essentially above or directly around the energy coil. Using the positioning fields, the relative position is thus calculated locally and therefore in the vicinity of the stationary inductive charging device, i.e. when the mobile inductive charging device is already in close proximity to the stationary inductive charging device. Such a main axis has the advantage, on the one hand, that the relative position is calculated more precisely, in particular because the respective volumes are more precisely defined. On the other hand, in this way, overlapping of adjacent inductive charging devices transversely to the height direction, for example between the positioning fields of adjacent stationary inductive charging devices, is prevented or at least reduced. The latter also leads to more accurate calculation of relative positions, as well as simpler, less disruptive and more reliable operation of multiple adjacent inductive charging devices, for example adjacent stationary inductive charging devices.

[0021] Advantageously, one coil is provided for each positioning field, which coil is also referred to below as a transmitting coil. An inductive charging device which generates at least two positioning fields therefore preferably has at least two transmitting coils, in particular one associated transmitting coil for each positioning field.

[0022] A main axis of the positioning field running along the height direction is preferably achieved in that the associated transmitter coil is wound around a winding axis running parallel or substantially parallel to the height direction, i.e. the transmitter coil has at least one conductor path that is conductive during operation and that is wound around a winding axis running parallel or substantially parallel to the height direction.

[0023] At least one of these transmission coils can be an energy coil of the associated inductive charging device.

[0024] Preferably, the transmission coil is different from the energy coil of the associated inductive charging device.

[0025] The fixed location, and in particular the intensity maximum, of the positioning field relative to the energy coil can be achieved in any manner.

[0026] Advantageously, a fixed position, in particular a strength maximum, of the positioning field relative to the energy coil of the associated inductive charging device is achieved by a corresponding positioning of the transmitting coil.

[0027] Essentially, identification of the relative positions of the energy coils to one another can be performed during the charging operation.

[0028] Preferably, the identification of the positions of the energy coils relative to one another is performed outside of the charging operation, i.e. in an operating mode different from the charging operation, which operating mode is also referred to in the following as the positioning operation.

[0029] The positioning operation is preferably resumed or started when the inductive charging devices fall below a preset distance from each other transversely to the height direction.

[0030] Preferably, here a pin signal is transmitted by one of the inductive charging devices, preferably a mobile inductive charging device, which pin signal is received by the other inductive charging device, and upon receipt of the pin signal a positioning operation is initiated.

[0031] The positioning operation is expediently completed when the energy coils are aligned with one another, after which the charging operation can begin.

[0032] Reception of the positioning field at the other inductive charging device may occur in any manner.

[0033] Advantageously, the inductive charging device which receives the positioning field has at least one receiver fixed relative to the associated energy coil, which receiver interacts with the positioning field of the other inductive charging device.

[0034] In particular, it is conceivable that an inductive charging device has only one such receiver.

[0035] Each at least one receiver may essentially be configured in any way.

[0036] For example, the at least one receiver of the at least one receiver may have at least one coil, hereinafter also referred to as a receiving coil. It is conceivable that the at least one receiver of the at least one receiver is such a receiving coil.

[0037] At least one of the at least one receiving coils can correspond to an energy coil of the associated inductive charging device, i.e. the energy coil of the inductive charging device can be used as an energy coil during a charging operation and as a receiving coil for identification purposes, i.e. during an identification operation.

[0038] Advantageously, the energy coil of the receiving inductive charging device is different from the at least one receiving coil.

[0039] The inductive charging device is used for inductive energy transfer, and during the charging operation, one of the energy coils acts as a primary coil and the other energy coil acts as a secondary coil. In particular, here, inductive energy is transferred from the stationary inductive charging device to the mobile inductive charging device. Variations are also conceivable in which the mobile inductive charging device transfers inductive energy to the stationary inductive charging device. Energy transfer in both directions is also conceivable.

[0040] The mobile inductive charging device is preferably installed in the associated mobile application, in particular in a motor vehicle, whereby inductive energy is preferably transferred to the application by means of the mobile inductive charging device, for example for charging the battery of the application, in particular in a motor vehicle.

[0041] In a preferred embodiment, a tolerance is allowed for at least one of the at least one ratio ranges. This makes it possible, in particular, to use the same stationary inductive charging device together with mobile inductive charging devices that are arranged at different heights, i.e. at different distances in the height direction, in the associated application. Thus, it is possible to achieve reliable and robust identification of the relative positions of the energy coils to one another, in particular when the mobile inductive charging device is used in vehicles of different heights, such as sports cars, SUVs or trucks.

[0042] Alternatively or additionally, it is conceivable for this purpose to pre-determine the respective associated ratio ranges for different distances between the energy coils in the height direction during the charging operation.

[0043] An embodiment is considered advantageous in which a virtual target volume is defined within the frame volume, extending in the height direction, in which case the energy coil of the inductive charging device generating the positioning field is at least partially within the target volume. Furthermore, at least one of the ratio ranges is pre-set in such a way that the energy coil of the inductive charging device receiving the positioning field is located within the target volume. That is to say, if the ratio is determined within a ratio range belonging to the target volume, an overlap of the energy coils in the transverse direction to the height direction within the target volume is identified. Since the target volume is smaller than the frame volume, an increased accuracy of the identification of the relative positions of the energy coils to one another is thereby achieved. It is thus further possible to more accurately align the energy coils relative to one another.

[0044] The frame volume and / or the target volume may be chosen essentially arbitrarily.

[0045] Expediently, the frame volume and the target volume are selected in such a way that high efficiency is obtained when the energy coil is overlapped inside the frame volume or the target volume during the charging operation.

[0046] Preferably, the frame volume and / or the target volume are selected such that an efficiency of at least 90% is achieved upon overlapping arrangement of the energy coils within the volume during a charging operation.

[0047] Here, the frame volume and the target volume can each be assigned an associated ratio range, whereby the at least one ratio range assigned to the target volume is expediently narrower than the at least one ratio range assigned to the frame volume.

[0048] For example, at least one of the at least one ratio range assigned to a target volume may be between 1:0.1 and 0.1:1.

[0049] For example, at least one of the at least one ratio ranges assigned to the frame volume may be between 10:0.05 and 0.05:10.

[0050] In a preferred embodiment, at least two of the opposing intensity maxima are assigned a direction, which makes it possible in particular to identify overlapping energy coils in said direction.

[0051] In a preferred embodiment, the positioning fields are therefore generated in such a way that the intensity maxima of at least two positioning fields are arranged opposite each other in a longitudinal direction extending transversely to the height direction, which are also referred to below as longitudinal positioning fields. Furthermore, for at least two of the longitudinal positioning fields, an associated ratio range is predefined in advance, which is also referred to below as longitudinal ratio range. From the received positioning fields, a ratio between at least two of the longitudinal positioning fields is determined, which is also referred to below as longitudinal ratio. As long as the determined longitudinal ratio lies within the predefined associated longitudinal ratio range, the energy coils are identified as overlapping in the longitudinal direction.

[0052] In a preferred embodiment, the positioning fields are therefore generated in such a way that the intensity maxima of at least two positioning fields are arranged opposite each other in a transverse direction extending transversely to the height direction, which are also referred to below as transverse positioning fields. Furthermore, for at least two of the transverse positioning fields, an associated ratio range is preset in advance, which is also referred to below as transverse ratio range. From the received positioning fields, a ratio is determined between at least two of the transverse positioning fields, which is also referred to below as transverse ratio. As long as the determined transverse ratio lies within the associated pre-set transverse ratio range, the energy coils are identified as overlapping in the transverse direction.

[0053] Preferably, at least two longitudinal positioning fields as well as at least two transverse positioning fields are generated, for the at least two longitudinal positioning fields the associated transverse ratio ranges are predefined, for the at least two transverse positioning fields the associated transverse ratio ranges are predefined, and at least one longitudinal ratio and at least one transverse ratio are determined from the received positioning fields, which leads to an increased accuracy of the identification of the relative positions of the energy coils with respect to one another.

[0054] Therefore, preferably, an overlap of energy coils is identified as long as the determined longitudinal ratio lies within a preset associated longitudinal ratio range and if the determined transverse ratio lies within a preset associated transverse ratio range.

[0055] Expediently, the longitudinal direction and the transverse direction run at an angle to one another. Advantageously, the longitudinal direction and the transverse direction run at least inclined to one another.

[0056] Preferably, the longitudinal direction and the lateral direction run transversely to one another, which allows for easy identification of the relative positions of the energy coils to one another, and in this way, the overlapping arrangement of the energy coils can also be easily performed by moving the inductive charging devices relative to one another.

[0057] Preferably, where the mobile inductive charging device is used in a vehicle, the longitudinal direction corresponds to the X-direction of the vehicle and the lateral direction corresponds to the Y-direction of the vehicle, or vice versa.

[0058] It is also contemplated that the longitudinal positioning field may be generated in a stationary inductive charging device and received in a mobile inductive charging device and the lateral positioning field may be generated in a mobile inductive charging device and received in a stationary inductive charging device, or vice versa.

[0059] In a preferred embodiment, all positioning fields are generated in one inductive charging device and received in the other inductive charging device, which leads to a simple implementation of the method.

[0060] Advantageously, the positioning field is generated in such a way that two pairs of intensity maxima spaced apart from one another in the longitudinal direction are arranged opposite each other and / or two pairs of intensity maxima spaced apart from one another in the transverse direction are arranged opposite each other. Thus, for the identification of the overlapping arrangement of the energy coils in the longitudinal direction and / or in the transverse direction, two ratios or corresponding ratio ranges are used respectively. This leads to an increased accuracy of the identification of the relative positions of the energy coils to one another.

[0061] Preferably, the positioning field is generated such that two pairs of intensity maxima spaced apart from one another in the longitudinal direction are arranged opposite each other and two pairs of intensity maxima spaced apart from one another in the lateral direction are arranged opposite each other.

[0062] Advantageously, the ratio of two positioning fields with opposite intensity maxima is determined, and if this ratio deviates above a preset limit value for identifying the relative position, the ratio of the positioning field with the lower intensity is used. Since the intensity maxima of each positioning field have a local profile in the form of a double projection, this prevents the ratio determined between the two projections from being used for identifying the relative position of the energy coils to each other. As a result, errors in identifying the relative position of the energy coils to each other are prevented or at least reduced.

[0063] Advantageously, the ratio of two positioning fields with opposite intensity maxima is determined, and if the ratios coincide within a preset value range for identifying the relative position, the two ratios are averaged. This leads to increased accuracy and robustness for identifying the relative position of the energy coil. The two ratios coincide are understood here to mean in particular that the two ratios are substantially identical or are within a preset average range.

[0064] To generate the longitudinal and lateral positioning fields, advantageously four transmission coils are used, although it is self-evident that it is also possible to use more than four positioning fields and thus more transmission coils.

[0065] Preferably, the transmitting coils are arranged here at the corners of a rectangle, so that the positioning field generated by each transmitting coil is both a lateral positioning field and a longitudinal positioning field, which leads to a simplified construction of the inductive charging device with the transmitting coils.

[0066] In an advantageous embodiment, if the determined ratio deviates from the associated ratio range towards the intensity maximum of one of the associated positioning fields, a deviation towards the intensity maximum to which the determined ratio is shifted is identified for the energy coil of the inductive charging device that receives the positioning field relative to the energy coil of the inductive charging device that generates the positioning field, i.e., not only the deviation between the energy coils relative to each other, but also the direction of the deviation is identified. In addition to increased accuracy in identifying the relative positions of the energy coils relative to each other, this makes it possible to carry out a relative movement of the mobile inductive charging device relative to the stationary inductive charging device so that this deviation is removed. In this way, a correspondingly simplified navigation of the mobile inductive charging device or the associated application is possible.

[0067] Preferably, the positioning signal is output as a function of the determined value of at least one ratio determined for the associated ratio range.

[0068] This positioning signal can be used via an output device as instructions for a person to navigate the mobile inductive charging device or associated application and / or as a control signal for automated navigation between the mobile inductive charging devices or associated applications, where the navigation leads to an overall overlapping arrangement of the energy coils relative to one another transverse to the height direction.

[0069] Preferably, the positioning field is generated such that at a preset centering longitudinal ratio in the longitudinal ratio range, there is a longitudinally centered arrangement of the energy coils, whereby a longitudinally centered superimposed arrangement of the energy coils relative to one another can be identified and / or navigation towards such an arrangement can be easily achieved.

[0070] Alternatively or additionally, preferably additionally, the positioning field is generated in such a way that at a preset centering lateral ratio in the lateral ratio range, there is a lateral centered arrangement of the energy coils relative to one another, whereby a lateral centered overlapping arrangement of the energy coils relative to one another can be identified and / or navigation towards such an arrangement can be easily achieved.

[0071] Overall, it is therefore possible to achieve a generally centered arrangement of the energy coils relative to one another transverse to the height direction, which leads to increased efficiency during the charging operation.

[0072] The respective centering ratios may essentially be chosen arbitrarily, in particular at least one of the centering ratios may be 1:1 or substantially 1:1, so that the centered location can be easily identified and / or navigation towards the centered location can be easily achieved.

[0073] In a preferred embodiment, the positioning fields are generated such that at least one of the ratio ranges, preferably each ratio range, is spaced apart from the intensity maximum of the associated positioning field, i.e. the intensity maximum is located outside at least one of the ratio ranges, preferably outside all of the ratio ranges. The intensity maximum of each positioning field thus has a local profile in the form of a double projection as explained above, so that the ratio determined between the two projections is avoided from being used for identifying the relative position of the energy coils to each other. As a result, errors in identifying the relative position of the energy coils to each other are prevented or at least reduced.

[0074] Basically, at least two of the positioning fields having different intensity profiles are generated.

[0075] In an advantageous embodiment, positioning fields are generated that have identical intensity profiles, thus achieving a simplified operation of the inductive charging device that generates the positioning field and / or a simplified reception and / or differentiation of the positioning fields.

[0076] Preferably, the positioning field is generated in such a way that the overall intensity profile of the positioning field is symmetrical with respect to the energy coil of the inductive charging device generating the positioning field, so that based on the symmetry of the overall intensity profile the relative positions of the energy coils to one another can be easily identified and / or navigation to a centered position can be easily performed.

[0077] The generation of mutually distinguishable positioning fields can be achieved in principle in any manner.

[0078] In particular, it is conceivable that the positioning fields are generated at different frequencies, so that they are distinguishable from one another.

[0079] Advantageously, the positioning field is generated at a frequency in the range between 5 kHz and 150 kHz. Preferably, the positioning field is generated at a frequency between 110 kHz and 148.5 kHz, particularly preferably between 120 kHz and 145 kHz.

[0080] The frequencies associated with the transmission coils are preferably spaced as close as possible from one another in order to reduce the overall required frequency spectrum, for example by 5 kHz, 1 kHz, 100 Hz, 1 Hz or even a few Hz from one another.

[0081] Alternatively or additionally, it is also conceivable to generate positioning fields in the respective associated scanning areas, so that these positioning fields are distinguishable from one another. The differentiation of the positioning fields is thus achieved by means of a so-called "duty cycle". The use of this duty cycle results in the positioning fields being able to be generated at the same frequency or in the same frequency band, which means that fewer frequencies are required. Furthermore, this results in, in particular, a reduced influence of the positioning device on nearby components.

[0082] In a preferred embodiment, the positioning field is generated in the stationary inductive charging device and received in the mobile inductive charging device. Since a relative movement of the mobile inductive charging device and the stationary inductive charging device occurs due to the mutual orientation of the energy coils, the determination of at least one ratio and the identification of whether an overlap of the energy coils exists can therefore be performed in the mobile inductive charging device. Compared to performing the corresponding calculation in the stationary inductive charging device and transmitting it to the mobile inductive charging device or the associated application, the result is therefore present in the mobile inductive charging device or the application. In other words, delays when the relative positions of the energy coils to each other are identified are prevented or at least reduced. This leads in particular to a smooth navigation of the mobile inductive charging device or the application with the mobile inductive charging device.

[0083] The method according to the invention can be used at any distance to identify the relative positions of the energy coils to each other, in particular for navigation and alignment of the energy coils to each other within any distance range.

[0084] Advantageously, the method is used for relative position identification and / or navigation in the so-called near field, ie at distances of less than 1.5 m, preferably less than 1.0 m, in particular less than 0.5 m.

[0085] An inductive charging device is typically a component of the system.

[0086] Preferably, in the system, the mobile inductive charging device is installed in the associated mobile application, in particular in a motor vehicle.

[0087] The method may be carried out by means of a suitably configured computer program product.

[0088] A computer program product for identifying a relative position between an energy coil of a stationary inductive charging device and an energy coil of a mobile inductive charging device advantageously includes instructions readable by a computer system that cause the computer system to perform the method when the computer program product is executed.

[0089] The computer program product is advantageously stored in a storage system having at least one non-volatile memory.

[0090] The computer program product advantageously contains instructions for causing the system to carry out the method.

[0091] It will be appreciated that computer program products also fall within the scope of the present invention.

[0092] It is understood that a system likewise falls within the scope of the invention.For the implementation of the method, the system can have a correspondingly configured control device.

[0093] The controller may include, at least in part, a computer program product and / or may comprise, at least in part, a computer system.

[0094] Moreover, it is self-evident that mobile applications of such systems, particularly automobiles, with mobile inductive charging devices are also within the scope of the present invention.

[0095] Further important features and advantages of the invention emerge from the dependent claims, the drawings and the associated description based on the drawings.

[0096] It is obvious that the features mentioned above and those to be further described below can be used not only in the respective described combinations, but also in other combinations or alone, without departing from the scope of the invention.

[0097] Preferred embodiments of the present invention are illustrated in the drawings and will be explained in more detail in the following description, where like reference numbers refer to identical or similar or functionally identical components. [Brief description of the drawings]

[0098] [Figure 1] FIG. 1 shows a highly simplified schematic diagram of a system for inductive energy transfer. [Diagram 2] FIG. 2 is a schematic diagram of a virtual volume. [Diagram 3] FIG. 2 is a simplified schematic plan view of a stationary inductive charging device of the system. [Figure 4] FIG. 1 is a schematic cross-sectional view of a stationary inductive charging device. [Diagram 5] FIG. 2 shows a schematic diagram with a positioning field. [Figure 6] FIG. 2 is a simplified schematic plan view of the transmit coil and receiver of the system; [Figure 7] FIG. 2 shows a schematic diagram with a positioning field received by a receiver; [Figure 8] FIG. 2 shows a schematic diagram with another positioning field received by the receiver. [Figure 9] FIG. 13 illustrates generally a flow chart for illustrating identification of the relative positions of an energy coil of a mobile inductive charging device and an energy coil of a stationary inductive charging device. [Figure 10] FIG. 2 is a schematic plan view of an energy coil of an inductive charging device having a transmitting coil.

[0099] The system 1, as shown in a highly simplified circuit diagram in Fig. 1, is used in particular for inductive energy transfer to a mobile application 100 in order to charge a battery 102 of the mobile application 100. In the illustrated embodiment, the application 100 is a motor vehicle 101. The system 1 comprises for this purpose two inductive charging devices 2 which inductively cooperate with one another during a charging operation, in particular a stationary inductive charging device 2, 2a and a mobile inductive charging device 2, 2b for the application 100. For the inductive energy transfer during the charging operation, each inductive charging device 2 has an associated coil 3, which are also referred to as energy coils 3 in the following. The stationary inductive charging devices 2, 2a thus have stationary energy coils 3, 3a and the mobile inductive charging devices 2, 2b have mobile energy coils 3, 3b. That is, one of the energy coils 3 is used as a primary coil 12 for generating an alternating magnetic field in the charging operation, which induces a voltage for energy transmission in the other energy coil 3, which is used as a secondary coil 13. In the illustrated embodiment, the energy coils 3 are each configured as flat coils 7. In the charging operation, the inductive charging devices 2 are spaced apart from one another in a height direction 200. In order to enable the charging operation and to achieve high efficiency during the charging operation, the energy coils 3 are positioned relative to one another transversely to the height direction 200, i.e. in a longitudinal direction 201 extending transversely to the height direction 200 and in a transverse direction 202 extending transversely to the height direction 200 and transversely to the longitudinal direction 201. For this purpose, the relative positions of the energy coils 3 to one another are identified. Advantageously, this is done before the charging operation in order to achieve an optimal relative positioning of the energy coils 3 to one another and thus increased efficiency.

[0100] In the illustrated embodiment, energy is transferred from the stationary inductive charging device 2, 2a to the mobile inductive charging device 2, 2b during a charging operation in order to charge the battery 102 of the motor vehicle 101. Accordingly, during the charging operation, the stationary energy coil 3, 3a is used as the primary coil 12 and the mobile energy coil 3, 3b is used as the secondary coil 13. As can be seen from FIG. 1 , the mobile inductive charging device 2, 2a in the illustrated embodiment comprises a rectifier 14 connected between the secondary coil 13 and the battery 102 in order to convert an alternating voltage induced in the secondary coil 13 into a rectified voltage. Furthermore, in the illustrated embodiment, the height direction 200 corresponds to the Z direction of the motor vehicle 101. Furthermore, the longitudinal direction 201 and the lateral direction 202 correspond, purely by way of example, to the X or Y direction of the motor vehicle 101.

[0101] In order to identify the relative positions of the energy coils 3 to one another, at least two fields 60 are generated in one of the inductive charging devices 2, which are explained in more detail below with reference to FIG. 5. These fields 60 are also referred to as positioning fields 60 in the following. The positioning fields 60 are generated in such a way that they are distinguishable from one another and that the energy coils 3 of the associated inductive charging device 2 are fixedly positioned relative to the positioning fields 60. Furthermore, the positioning fields 60 are generated in such a way that the energy coils 3 of the associated inductive charging device 2 are at least partially located in a virtual volume 51 that is defined by at least two intensity maxima 61 of at least two of the positioning fields 60 and extends in the height direction 200, which virtual volume 51 is explained in more detail below with reference to FIG. 2. The volume 51 is also referred to as frame volume 51 in the following. These positioning fields 60 are received at least one position that is fixed relative to the energy coils 3 of the other inductive charging device 2. Here, a ratio range 63 (see FIG. 5 ) of at least two of the received positioning fields 60 is predefined in such a way that the energy coil 3 of the inductive charging device 2, which receives the positioning magnetic field 60, is located in the frame volume 51. To identify the relative positions of the energy coils 3 with respect to one another, a ratio 62 between the at least two of the received positioning fields 60 is determined. If at least one ratio of the at least one determined ratio 62 lies within the corresponding predefined ratio range 63, it is identified that the energy coil 3 is located in the frame volume 51 and overlaps transversely with respect to the height direction 200. In the illustrated embodiment, the respective positioning fields 60 are magnetic positioning fields 60. The predefinition of the respective ratio range 63 is performed by a fixed setting, so that the ratio range 63 is stored and a calibration is omitted.

[0102] In the illustrated embodiment, each positioning field 60 is generated by means of an associated coil 5, which is also referred to below as a transmitting coil 5. In the illustrated embodiment, each positioning field 60 is received by means of at least one receiver 6, which interacts with the positioning field 60 and which is configured as a coil 15 in the illustrated embodiment and which is also referred to below as a receiving coil 15. The transmitting coil 5 and the at least one receiving coil 15 may here be components of a positioning device 4 of the system 1 (see FIG. 1 ).

[0103] As can be seen, for example, from Fig. 2, in the illustrated embodiment, a total of four transmission coils 5 are provided, in particular a first transmission coil 5,5a, a second transmission coil 5,5b, a third transmission coil 5,5c and a fourth transmission coil 5,5d. Thus, a total of four mutually distinguishable positioning fields 60 are generated, in particular a first positioning field 60,60a, a second positioning field 60,60b, a third positioning field 60,60c and a fourth positioning field 60,60d (see Figs. 7 and 8). Furthermore, in the illustrated embodiment, only one receiver 6 is provided for receiving the positioning field 60. Due to the differences between these positioning fields 60, here, it is possible to distinguish between these positioning fields 60 by using at least one receiver 6.

[0104] In the illustrated embodiment, these positioning fields 60 are generated at one of the inductive charging devices 2 and received at the other inductive charging device. These positioning fields 60 are generated at the mobile inductive charging device 2, 2a and received at the stationary inductive charging device 2, 2b. Accordingly, the stationary inductive charging device 2, 2a has a transmitting coil 5 and the mobile inductive charging device 2, 2b has at least one receiver 6. In the illustrated embodiment, these transmitting coils 5 are different from the first energy coil 3, 3a. In the illustrated embodiment, the at least one receiving coil 15 is different from the second energy coil 3a, 3b, merely by way of example. For example, as shown in FIG. 2, the transmitting coils 5 are spaced apart from one another, with two transmitting coils 5 each arranged opposite one another.

[0105] In the embodiment shown, the transmitter coils 5 have the same configuration, i.e. are identical components. Here, each transmitter coil 5 is a flat coil 7 which has at least one conductor path, not shown in detail, which is wound around an associated winding axis (not shown) running parallel to the height direction 200. Each positioning field 60 therefore has a main axis running along the height direction 200, i.e. extends at least mainly in or along the height direction 200, and is therefore only locally receivable transversely to the height direction 200.

[0106] The mutually distinguishable generation of the positioning fields 60 is achieved in the illustrated embodiment in that each magnetic positioning field 60 is generated at an associated frequency, i.e. each transmission coil 5 is operated at an associated frequency, whereby the positioning fields 60 are mutually distinguishable. Here, these frequencies are in particular in the range between 120 kHz and 145 kHz and are spaced from one another, for example by a few Hz to a few kHz. For example, these frequencies can be spaced from one another by 5 kHz, 1 kHz, 100 Hz or even less. Likewise, a distinction by means of the duty cycle is also possible.

[0107] FIG. 2 is a schematic diagram showing only the transmitting coil 5 of the system 1 and the energy coil 3 of an inductive charging device 2 with a transmitting coil 5, ie in the illustrated embodiment only the stationary energy coil 3, 3a.

[0108] In the illustrated embodiment, each positioning field is generated by an associated transmitting coil 5, and the geometric arrangement of the positioning field 60 and the transmitting coils 5 is considered to be similar, so that, for example, the positioning field 60 generated by two opposing transmitting coils 5 has opposing intensity maxima 61 parallel to the opposing arrangement of the transmitting coils 5.

[0109] As can be seen from FIG. 2, the arrangement of the transmitter coils 5 is such that they define a virtual frame 50. The frame 50 is thus a virtual plane that is defined by the transmitter coils 5. The virtual frame 50 here defines a frame volume 51 that extends in a height direction 200 starting from the frame 50. Here, the energy coils 3 of the associated inductive charging device 2, i.e. in the illustrated embodiment the stationary energy coils 3, 3a, are at least partially arranged in the virtual frame volume 51. The energy coils 3 of the associated inductive charging device 2 are therefore at least partially offset in the frame 50 or in the height direction 200 relative to the frame 50 and are therefore arranged in the frame volume 51. In the illustrated embodiment, the transmitter coils 5 are spaced apart in the height direction 200 from the energy coils 3 of the associated inductive charging device 2, and thus from the stationary energy coils 3, 3a. In the illustrated embodiment, moreover, two of the transmitter coils 5 are arranged opposite each other in the longitudinal direction 201 and in the transverse direction 202. The transmitting coils 5 facing in the longitudinal direction 201 are hereinafter also referred to as longitudinal transmitting coils 5,5x, and the transmitting coils 5 facing in the transverse direction 202 are hereinafter also referred to as transverse transmitting coils 5,5y. Subsequently, the positioning fields 60 generated by the longitudinal transmitting coils 5,5x are hereinafter also referred to as longitudinal positioning fields 60,60x relative to one another, and the positioning fields 60 generated by the transverse transmitting coils 5,5y are hereinafter also referred to as transverse positioning fields 60,60y relative to one another.

[0110] As shown for example in FIG. 2, these transmitting coils 5 are arranged in the corners 57 of a quadrangle 54 shaped as a rectangle 55 in the illustrated embodiment, so that the frame 50 has the shape of a rectangle 55. The frame volume 51 is thus cuboid-shaped. In the embodiment of FIG. 2, the frame 50 has the shape of a square 56. Due to the arrangement of the transmitting coils 5 in the corners 57 of the rectangle 55, each transmitting coil 5 is both a longitudinal transmitting coil 5, 5x and a transverse transmitting coil 5, 5y. Thus, with four transmitting coils 5, there are two pairs of transmitting coils 5 facing each other in the longitudinal direction 201 and the transverse direction 202. Similarly, each positioning field 60 is both a longitudinal positioning field 60, 60x and a transverse positioning field 60, 60y. Thus, in the longitudinal direction 201, two pairs of intensity maxima 61 spaced apart from one another are arranged opposite each other, and in the lateral direction 202, two pairs of intensity maxima 61 spaced apart from one another are arranged opposite each other.

[0111] Based on the at least one determined ratio 62, it is furthermore determined whether an energy coil 3 of an inductive charging device 2 with at least one receiver 6 is present inside the virtual frame volume 51 and, depending on this, a positioning signal is output. In the illustrated exemplary embodiment, this means that based on the at least one ratio 62, it is determined whether a mobile energy coil 3, 3b is present inside the frame volume 51 and thus is arranged above a stationary energy coil 3, 3a in the height direction 200 and further at least partially overlaps the stationary energy coil 3, 3a transversely to the height direction 200.

[0112] As can be seen from Fig. 2, in the illustrated embodiment, a virtual target area 52 is defined inside the frame 50. This target area 52 is therefore smaller than the frame 50. Here, the target area 52 inside the frame volume 51 defines a virtual volume 53 extending in the height direction 200, which virtual volume 53 is also called target volume 53 in the following and is shown by a dashed line in Fig. 2. The energy coil 3 of the inductive charging device 2 with the transmission coil 5, i.e. in the illustrated embodiment the stationary energy coil 3, 3a, is here at least partially arranged in the target volume 53. Here, a respective ratio range 63 is predefined such that the energy coil 3 of the inductive charging device 2 receiving the positioning field 60 is arranged in the target volume.

[0113] The frame volume 51 as well as the target volume 53 are defined in such a way that with a corresponding arrangement of the energy coils 3 in the frame volume 51 and the target volume 53, a high efficiency, for example at least 90%, is achieved during the charging operation. The target volume 53 is selected here in such a way that with an arrangement of two energy coils 3 in the target volume 53, the efficiency is greater than with an arrangement of two energy coils 3 in the frame volume 51. As indicated in Fig. 3, the target volume 53 and thus the target area 52 in the projection in the height direction 200 is smaller than the associated inductive charging device 2, i.e. in the illustrated embodiment, smaller than the stationary inductive charging device 2, 2a.

[0114] The positioning signal can be used for manual movement of the application 100 or for autonomous movement of the application 100. That is to say, in the embodiment of the automobile 101, the positioning signal can be used to signal to a vehicle driver, not shown, whether a desired orientation of the energy coils 3 with respect to one another is present or not. For this purpose, the automobile 101 can have an output device 103, as suggested in Fig. 1, which outputs a corresponding signal.

[0115] The identification of the superposition of the energy coils 3 is explained on the basis of Fig. 5. In Fig. 5, the course of two positioning fields 60 is shown, which are generated by two opposing transmitting coils 5 in the longitudinal direction 201 or in the transverse direction 202. In Fig. 5, the illustrated positioning fields 60 are thus selectively either the longitudinal positioning fields 60, 60x or the transverse positioning fields 60, 60y. Here, one of these positioning fields 60 is shown with a dashed line for better differentiation. Fig. 5 shows here the intensity course 64 of the longitudinal positioning fields 60, 60x along the longitudinal direction 201 or the intensity course 64 of the transverse positioning fields 60, 60y along the transverse direction 202. According to Fig. 5, the positioning fields 60 of the opposing transmitting coils 5 coincide in the target volume 53. As can be seen from Fig. 5, the positioning fields 60 have the same intensity course 64, i.e. the positioning fields 60 are generated with the same field distribution in each case. Furthermore, in the illustrated embodiment, the transmitting coils 5 are configured and the positioning field 60 is generated such that the total intensity profile 66 of the positioning field 60 generated by the transmitting coils 5 is symmetric between the opposing transmitting coils 5 and thus between the intensity maxima 61, as well as symmetric with respect to the stationary energy coils 3, 3b.

[0116] As can be seen further from FIG. 5, each positioning field 60 has an intensity profile 64 with intensity edges 65 leading to intensity maxima 61. As can be seen further from FIG. 5, the intensity maxima 61 are spaced apart from one another. The transmitting coils 5 are arranged and / or the positioning fields 60 are generated accordingly. As can be seen further from FIG. 5, the intensity maxima 61 of the respective positioning field 60 are shaped in the form of a double projection. This is due, inter alia, to the fact that the receiver 6 senses a shift in the magnetic field lines (not shown) during the corresponding positioning. As can be seen from FIG. 5, here each ratio range 62 is arranged between successive intensity edges 65 of the positioning field 60 generated by the corresponding corresponding transmitting coil 5 and spaced apart from the intensity maxima 61. Here, for longitudinal positioning fields 60, 60x with opposing intensity maxima 61 in the longitudinal direction 201, the respective associated longitudinal ratio ranges 63, 63x are pre-defined, and for transverse positioning fields 60, 60y with opposing intensity maxima 61 in the transverse direction 202, the respective associated transverse ratio ranges 63, 63y are pre-defined. The pre-defined ratio ranges 63 here are preferably stored, so that by a simple comparison between the determined ratios 62 and the associated ratio ranges 63 it is possible to determine whether a corresponding overlap exists between the energy coils 3.

[0117] That is, the longitudinal transmitting coils 5, 5x are arranged such that the intensity maxima 61 of the two longitudinal positioning fields 60, 60x in the longitudinal direction 201 are arranged opposite each other, and the longitudinal positioning fields 60, 60x are generated. Here, for at least two of the longitudinal positioning fields 60, 60x, the associated longitudinal ratio range 63, 63x is predefined in advance. From the longitudinal positioning fields 60, 60x received by the receiver 6, the longitudinal ratio 62, 62x between at least two of the longitudinal positioning fields 60, 60x is determined. The overlap of the energy coils 3 in the longitudinal direction 201 inside the target volume 53 is identified if the determined longitudinal ratio 62, 62x is within the associated predefined longitudinal ratio range 63, 63x. The same applies to the overlap in the transverse direction 202. That is, the transverse transmission coils 5, 5y are arranged and / or the transverse positioning fields 60, 60y are generated such that the intensity maxima 61 of the two transverse positioning fields 60, 60y in the transverse direction 202 are arranged opposite each other. Furthermore, an associated transverse ratio range 63, 63y is predefined in advance for at least two of the transverse positioning fields 60, 60y. During the positioning operation, a transverse ratio 62, 62y between at least two of the transverse positioning fields 60, 60y is determined from the transverse positioning fields 60, 60y received by the receiver 6. Here, a superposition 3 of the energy coils 3 inside the target volume 53 in the transverse direction 202 is identified if the determined transverse ratio 62, 62y is within the associated predefined transverse ratio range 63, 63y. In other words, overlap of the energy coils 3 in the longitudinal direction 201 and the lateral direction 202 exists when at least one of the longitudinal ratios 62, 62y is within the longitudinal ratio range 63, 63y, and when at least one of the lateral ratios 62, 62y is within the lateral ratio range 63, 63y.

[0118] For example, here, for overlap within the frame volume 51, a ratio range 63 between 10:0.05 and 0.05:10 may be given, and for overlap within the target volume 53, a ratio range 63 between 1:0.1 and 0.1:1 may be given.

[0119] Fig. 6 shows a simplified plan view in a height direction 200 relative to the transmitter coil 5. Here, it is assumed that the receiver 15 moves between the first transmitter coil 5,5a and the second transmitter coil 5,5b along the longitudinal direction 201. Fig. 7 shows the positioning fields 60 of the first transmitter coil 5,5a and the second transmitter coil 5,5b, received by the receiver 15 during said movement along the longitudinal direction 201, and thus the first positioning fields 60,60a and the second positioning fields 60,60b. Fig. 8 shows the positioning fields 60 of the third transmitter coil 5,5c and the fourth transmitter coil 5,5b, received during said movement of the receiver 15 along the longitudinal direction 201, and thus the fourth positioning fields 60,60c and the fourth positioning fields 60,60d. The first positioning field 60,60a and the second positioning field 60,60b are mutually longitudinal positioning fields 60,60x. Similarly, the third positioning field 60,60c and the fourth positioning field 60,60d are mutually longitudinal positioning fields 60,60x. As a comparison of Fig. 7 and Fig. 8 shows, the double-convex shape of the positioning field 60 received by the receiver 15 is more pronounced for the positioning field 60 closer to the receiver 15 than for the positioning field 60 further away from the receiver 15. That is to say, in the described example, the double-convex shape for the received first positioning field 60,60a and the second positioning field 60,60b is more pronounced than for the received third positioning field 60,60c and the fourth positioning field 60,60d. Here, in Fig. 8, the double-protruding shapes of the positioning fields 60 further apart, i.e., for example, the double-protruding shapes of the third positioning field 60, 60c and the fourth positioning field 60, 60d, are not shown for better understanding. Accordingly, the ratio 62 of two positioning fields 60 with opposite intensity maxima 61 is preferably determined, and in the event of a deviation of the ratio 62 above a preset limit value for identifying the relative position, the ratio 62 of the positioning field 60 with the lower intensity is used. As a result, the positioning field 60 whose determined ratio 62 is further apart relative to the intensity maxima 61 is used. This prevents, in particular, the above-described double-protruding shape of the intensity maxima 61 from leading to erroneous position identification.On the other hand, if the two ratios 62 are substantially corresponding to each other, i.e., if the ratios 62 are substantially the same or within a preset value range, the two ratios 62 are averaged in order to identify the relative position.

[0120] Furthermore, if the determined ratio 62 deviates from the associated ratio range 63 towards the intensity maximum 61 of the associated positioning field 60, then a deviation of the energy coil 3 of the receiving side, and thus of the inductive charging device 2 with the receiver 6, towards the intensity maximum 61 to which the ratio 62 is shifted, and thus towards the transmitting coil 5 which generates the intensity maximum 61 to which the ratio 62 is shifted, is also identified. In other words, the determined longitudinal ratio 62, 62x is shifted from the associated longitudinal ratio range 63, 63x towards the intensity maximum 61 of the associated longitudinal positioning field 60, 60x, which means that there is a deviation of the mobile energy coil 3, 3b along the longitudinal direction 201 from the target volume 53 towards the longitudinal transmitting coil 5, 5x which generates the longitudinal positioning field 60, 60x with the intensity maximum 61 to which the determined longitudinal ratio 62, 62x is shifted. The same applies for the determined transverse ratio 62, 62y, i.e. the determined transverse ratio 62, 62y is shifted from the associated transverse ratio range 63, 63y towards one of the intensity maxima 61 of the associated transverse positioning fields 60, 60y, which means that there is a displacement of the mobile energy coil 3, 3b along the transverse direction 202 from the target volume 53 towards the transverse transmitting coil 5, 5y which generates the transverse positioning field 60, 60y with the intensity maximum 61 to which the determined transverse ratio 62, 62y is shifted. Thus, navigation of the mobile inductive charging device 2, 2a can be realized such that an overlap of the two energy coils 3 in the target volume is achieved, thus both in the longitudinal direction 201 and in the transverse direction 202. This can be done using the output device 103 to output whether and in what direction a relative movement of the mobile inductive charging device 2, 2b relative to the stationary inductive charging device 2, 2a is required to achieve an overlap of the energy coils 3 in the longitudinal direction 201 and the lateral direction 202 as suggested in Fig. 1. In the embodiment shown in Fig. 1 this is done optically using the indication of the arrows suggested in Fig. 1, purely by way of example.Likewise, it is conceivable that the output device 103 outputs an acoustic signal. It is also conceivable that the result is realized autonomously, whereby the vehicle 101 drives autonomously to achieve the superposition of the energy coils 3.

[0121] The maximum efficiency during the charging operation is achieved at a corresponding relative position of the energy coils 3 to one another, which is also referred to below as a centered arrangement. This centered arrangement is here assigned to each ratio 63 within the ratio range 63. That is to say, at a preset centered longitudinal ratio in the longitudinal ratio range 63, 63x, there is a mutually centered arrangement of the energy coils 3 in the longitudinal direction 201. Furthermore, at a preset centered transverse ratio in the transverse ratio range 63, 63y, there is a mutually centered arrangement of the energy coils 3 in the transverse direction 202. Thus, a centered arrangement is generally present if at least one of the determined longitudinal ratios 62, 62x also corresponds to the associated centered longitudinal ratio and at least one of the determined transverse ratios 62, 62y also corresponds to the associated centered transverse ratio. The respective centering ratio is, in the illustrated embodiment, 1:1, as suggested in Fig. 5. Similar to the above explanation, navigation can now be realized such that there is a generally centered arrangement of the energy coils 3.

[0122] In Fig. 9, a flow chart is shown for explaining the identification of the relative positions of the energy coils 3 to one another. The positioning operation is initiated when the application 100, and thus the mobile inductive charging device 2, 2b, approaches the stationary inductive charging device 2, 2a. This is the case, for example, when the distance between the inductive charging devices 2 transversely to the height direction 200 is less than 1.5 m, in particular less than 1 m, preferably less than 0.5 m. The positioning operation can be initiated, for example, by means of a pin signal output by the mobile inductive charging device 2, 2b, which, upon reception of the pin signal, generates a positioning field 60 by means of the transmitting coil 5. In a method means 300, also referred to below as receiving means 300, the positioning field 60 is received by means of a receiver 6 and in a subsequent method means 301 the positioning fields 60 are separated from one another such that their intensities are distinguishable from one another. In the method means 301, in particular, a Fourier transformation of the signal received by the receiver 6 is carried out here, i.e. in the receiving coil 15, the voltage induced in said receiving coil 6 by means of the positioning field 60 is Fourier transformed. The method means 301 is also referred to below as a separation means 301. The result of the separation means 301 is therefore an associated value for each positioning field 60, so that there are four values ​​in total. From these values, in the method means 302, the associated longitudinal ratios 62, 62x and transverse ratios 62, 62y are determined for the longitudinal positioning fields 60, 60x and for the transverse positioning fields 60, 60y. Here, advantageously, an averaging is carried out over a number of values ​​in each case, for example over the last ten determined values, in order to increase the accuracy of the method and / or to reduce the error rate. The method means 302 is also referred to below as a ratio means 302. The ratio 62 determined in the ratio means 102 is compared in a method means 303 with a corresponding predefined ratio range 63, and based on this comparison it is determined whether there is a corresponding overlap of the energy coils 3, i.e. an arrangement of the mobile energy coils 3, 3b inside the target volume 53. This method means 303 is also referred to as a comparison means 303 in the following.The comparison means 303 here outputs at least one positioning signal, as suggested in Fig. 9. This positioning signal is here preferably used for navigation of the mobile application 100, as explained above. The positioning signal can be provided accordingly to the output device 103.

[0123] To perform the relative position identification, a correspondingly configured control device 16 can be used, which is shown in a simplified form in Fig. 1. This control device 16 may be a component of the positioning device 4 of the system 1 or application 100. Here, the method can be implemented by means of a computer program product.

[0124] Corresponding to FIG. 4, the inductive charging device 2 with a transmitting coil 5, i.e. in this embodiment a stationary inductive charging device 2, 2a, has as energy coil 3 in the illustrated embodiment a flat coil 7 which is larger than the transmitting coil 5. Furthermore, the stationary inductive charging device 2, 2a has a flux guiding unit 8 for guiding the alternating magnetic field generated by the stationary energy coil 3, 3a during the charging operation. For this purpose, in the illustrated embodiment, the flux guiding unit 8 has a flux guiding element 9 which is formed as a ferrite plate 10. Here, the transmitting coil 5 overlaps the stationary energy coil 3, 3a, is arranged at a corner 57 of a rectangle 55 (see, for example, FIG. 2) and is arranged in a plane running parallel to the stationary energy coil 3, 3a. Furthermore, the transmitting coil 5 is arranged on the upper side of the flux guiding unit 9.

[0125] 4 shows possible relative positions of the transmitting coil 5 with respect to the stationary energy coil 3, 3a. Accordingly, the transmitting coil 5 can be arranged in the height direction 200 between the stationary energy coil 3, 3a and the flux guiding unit 8, either on the side of the flux guiding unit 8 opposite the stationary energy coil 3, 3a or on the side of the external object identification device 17 of the stationary inductive charging device 2, 2a facing the stationary energy coil 3, 3a.

[0126] FIG. 10 shows a further embodiment, which differs from the previous one in that the transmission coil 5 is arranged offset towards the inside.

Claims

1. A method for identifying the relative positions of a stationary inductive charging device (2, 2a) and a mobile inductive charging device (2, 2b), comprising: The stationary inductive charging device (2, 2a) has a stationary energy coil (3, 3a), and the mobile inductive charging device (2, 2b) has a mobile energy coil (3, 3b), During the charging operation of the system (1), one of the energy coils (3) generates an alternating magnetic field, which induces a voltage in the other energy coil (3) for energy transfer; The energy coils (3) are spaced apart from each other in a height direction (200) during charging operation; In one of the inductive charging devices (2), at least two positioning fields (60) are generated, the positioning fields (60) being distinguishable from one another, and the energy coil (3) of the associated inductive charging device (2) is fixedly positioned relative to the positioning fields (60), the energy coil (3) being at least partially defined by at least two intensity maxima (61) of at least two of the positioning fields (60) and located within a virtual frame volume (51) extending in the height direction (200); The positioning field (60) is received at least one position that is fixed relative to the energy coil (3) of the other inductive charging device (2); a ratio range (63) of at least two of the received positioning fields (60) is preset such that the energy coil (3) of the inductive charging device (2) receiving the positioning field (60) is positioned within the frame volume (51); determining a ratio (62) between at least two of the received positioning fields (60); The method of claim 1, wherein the energy coil (3) is identified as being arranged in the frame volume (51) and overlapping laterally with respect to the height direction (200) if at least one ratio of the at least one determined ratio (62) is within a predetermined associated ratio range (63).

2. a virtual target volume (53) extending in the height direction (200) within the frame volume (51), wherein the energy coil (3) of the inductive charging device (2) generating the positioning field (60) is at least partially present within the target volume (53); 2. The method of claim 1, wherein at least one of the ratio ranges (63) is preset so that the energy coil (3) of the inductive charging device (2) receiving the positioning field (60) is positioned within the target volume (53).

3. the positioning field (60) is generated such that intensity maxima (61) of at least two longitudinal positioning fields (60, 60x) are arranged oppositely in a longitudinal direction (201) extending transversely to the height direction (200); for at least two of the longitudinal positioning fields (60, 60x), a corresponding longitudinal ratio range (63, 63x) is predefined, determining a longitudinal ratio (62, 62x) between at least two of the longitudinal positioning fields (60, 60x) from the received positioning fields (60); 3. The method according to claim 1, wherein the energy coils are identified as overlapping in the longitudinal direction if the determined longitudinal ratio is within the predetermined associated longitudinal ratio range.

4. The positioning field (60) is generated such that intensity maxima (61) of at least two lateral positioning fields (60, 60y) are arranged oppositely in a lateral direction (202) extending transversely to the height direction (200); for at least two of the lateral positioning fields (60, 60y), a corresponding lateral ratio range (63, 63y) is predefined, determining a lateral ratio (62, 62y) between at least two of the lateral positioning fields (60, 60y) from the received positioning fields (60); 3. The method according to claim 1, wherein the energy coils are identified as overlapping in the lateral direction if the determined lateral ratio is within the predetermined associated lateral ratio range.

5. the determined longitudinal ratio (62, 62x) is within the associated predetermined longitudinal ratio range (63, 63x), 4. The method according to claim 3, wherein the energy coils are identified as overlapping if the determined lateral ratio (62, 62y) is within the predetermined associated lateral ratio range (63, 63y).

6. 3. The method according to claim 1, wherein the positioning field (60) is generated such that two pairs of intensity maxima (61) spaced apart from one another in the longitudinal direction (201) are arranged opposite each other and / or two pairs of intensity maxima (61) spaced apart from one another in the transverse direction (202) are arranged opposite each other.

7. 7. The method according to claim 6, wherein a ratio (62) of two positioning fields (60) having opposite intensity maxima (61) is determined, and if the ratio (62) deviates by more than a preset limit value for identifying a relative position, the ratio (62) of the positioning field (60) having the lower intensity is used.

8. 7. The method of claim 6, wherein a ratio (62) of two positioning fields (60) having the opposing intensity maxima (61) is determined, and if the ratios (62) match within a range of values ​​for identifying relative positions, the two ratios (62) are averaged.

9. 3. The method according to claim 1, further comprising: if the determined ratio (62) deviates from the associated ratio range (63) toward an intensity maximum (61) of one of the associated positioning fields (60), a deviation toward an intensity maximum (61) of an energy coil (3) of an inductive charging device (2) that receives the positioning field (60) relative to an energy coil (3) of an inductive charging device (2) that generates the positioning field (60) is identified, at which point the determined ratio (62) is shifted.

10. 3. The method according to claim 1, wherein the positioning signal is output as a function of the determined value of at least one ratio (62) determined for the associated ratio range (63).

11. 11. The method according to claim 10, wherein the positioning signal is used via an output device (103) as an instruction for navigating the mobile inductive charging device (2, 2b) and / or as a control signal for automated navigation of the mobile inductive charging device (2, 2b) for mutually overlapping arrangement of the energy coils (3).

12. The positioning field (60) At a preset centering longitudinal ratio in the longitudinal ratio range (63, 63x), there is a centered arrangement of the energy coil (3) in the longitudinal direction (201), and / or 4. The method according to claim 3, wherein a preset centering lateral ratio in the lateral ratio range (63, 63y) is generated such that there is a mutually centered arrangement of the energy coils (3) in the lateral direction (202).

13. 3. The method according to claim 1, wherein the positioning field (60) is generated such that at least one of the ratio ranges (63) is spaced apart from an intensity maximum (61) of the associated positioning field (60).

14. 3. The method according to claim 1, wherein positioning fields (60) having the same intensity profile (64) are generated.

15. 3. The method according to claim 1, wherein the positioning field (60) is generated such that the overall intensity profile (66) of the positioning field (60) is symmetrical with respect to the energy coil (3) of the inductive charging device (2) that generates the positioning field (60).

16. 3. The method of claim 1 or 2, wherein the positioning fields (60) are generated at different frequencies so that they are distinguishable from one another within the inductive charging device (2) receiving the positioning fields (60).

17. 3. The method according to claim 1, wherein the positioning fields (60) are generated in the respective associated scanning areas, whereby the positioning fields (60) are distinguishable from one another.

18. 3. The method of claim 1 or 2, wherein the positioning field (60) is generated at the stationary inductive charging device (2, 2a) and received at the mobile inductive charging device (2, 2b).

19. 3. The method of claim 1 or 2, wherein the positioning field (60) is generated at the mobile inductive charging device (2, 2b) and received at the stationary inductive charging device (2, 2a).

20. 3. The method according to claim 1 or 2, wherein at least one of the positioning fields (60), in particular each positioning field (60), is generated as a magnetic positioning field (60).

21. The method of claim 1 or 2, wherein each of the positioning fields (60) is generated with a major axis extending along the height direction (200).

22. A computer program product configured to perform the method of claim 1 or 2.

23. A system (1) comprising a stationary inductive charging device (2, 2a), a mobile application (100), in particular a motor vehicle (101), and a mobile inductive charging device (2, 2b), the stationary inductive charging device (2, 2a) has a stationary energy coil (3, 3a), and the mobile inductive charging device (2, 2b) has a mobile energy coil (3, 3b), the energy coils being spaced apart from each other in a height direction (200) during a charging operation and inductively cooperating to inductively transfer energy to the application (100); One of the inductive charging devices (2) has at least two transmitting coils (5) that generate mutually distinguishable positioning fields (60) during a positioning operation; The other inductive charging device (2) has at least one receiver (6) for receiving the positioning field (60); A system (1) comprising a control device (12) configured to operate the system (1) according to the method of claim 1 or 2 during a positioning operation.

24. A mobile application (100), in particular a motor vehicle (101), comprising a mobile inductive charging device (2, 2b) of the system (1) according to claim 21.

25. A stationary inductive charging device (2, 2a) of a system (1) according to claim 21.

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