Method for detecting relative position of stationary inductive charging device with respect to mobile inductive charging device

Abstract

The invention relates to a method for detecting a relative position of a stationary inductive charging device (2, 2a) with respect to a mobile inductive charging device (2, 2b), the stationary inductive charging device and the mobile inductive charging device interacting with each other in a charging mode for inductively transmitting energy. A precise and robust identification of the relative position of the energy coils (3) of the inductive charging device (2) with respect to each other is achieved by generating at least two fixed positioning fields (60) with respect to one of the energy coils (3), receiving the positioning fields (60) at a fixed location with respect to the other energy coil (4), a ratio (62) between the positioning fields (60) is ascertained, and if the ascertained ratio (62) corresponds to a predetermined ratio range (63), an overlap of the two energy coils (3) is detected. The invention further relates to a computer program product for carrying out the method, to a system (1) operated in such a way, and to a mobile application device (100) of a mobile inductive charging device (2, 2a) having such a system (1). The invention further relates to a stationary inductive charging device (2, 2a) of such a system (1).

Description

Technical Field

[0001] The invention relates to a method for detecting the relative position of a stationary inductive charging device relative to a mobile inductive charging device, wherein the stationary inductive charging device and the mobile inductive charging device interact with each other during a charging operation for the inductive transfer of energy. The invention also relates to a computer program product for implementing the method, a system operating according to the method and having a stationary inductive charging device and a mobile inductive charging device, and a mobile application, in particular a motor vehicle, having a mobile inductive charging device of such a system and a stationary inductive charging device of such a system. Background Art

[0002] Typically, a system for inductive energy transmission has a stationary inductive charging device and a mobile inductive charging device. During charging operation, the energy coil of one of the inductive charging devices is used as a primary coil, and the energy coil of the other inductive charging device is used as a secondary coil. Typically, this type of system is used for inductive energy transmission to a mobile application device, for example, to a motor vehicle, wherein the mobile application device has a mobile inductive charging device. In the mobile application device, the energy coil of the mobile inductive charging device is usually a secondary coil during charging operation. For inductive energy transmission, the primary coil generates an alternating magnetic field, which induces a voltage in the secondary coil. In order to enable inductive energy transmission and to increase the efficiency of inductive energy transmission, the primary coil and the secondary coil and therefore the energy coil of the inductive charging device must be positioned accordingly relative to each other.

[0003] In EP 2 727 759 B1, a transmitter and a receiver are used to detect the relative position of a mobile inductive charging device installed in a motor vehicle.

[0004] DE 10 2012 205 283 A1 proposes using an even number of detector coil elements which are wound in pairs in opposite directions and form detector pairs.

[0005] EP 3 347 230 B1 proposes using a transmitting unit in a mobile inductive charging device, which transmits a transmission signal with a defined frequency during operation. The transmission signal with the defined frequency is received by means of a receiving unit, and signal parts of the transmission signal are determined. In this case, the relative position is determined based on the determined signal parts.

[0006] DE 10 2017 215 932 B3 describes a method for determining position information of a motor vehicle on a substrate. The motor vehicle has a mobile inductive charging device. By energizing the power coil of the mobile inductive charging device, at least one magnetic structure arranged in or on the substrate over which the motor vehicle drives is magnetized. The structure is stored in a digital map together with the position information of the corresponding structure, wherein the position of the motor vehicle is determined based on the magnetized structure. Summary of the invention

[0007] The present invention is directed to the object of providing an improved or at least different embodiment for a method for detecting the relative position of a stationary inductive charging device relative to a mobile inductive charging device, for a computer program product for implementing the method, for a system operating in this manner and having a stationary inductive charging device and a mobile inductive charging device, and for a mobile application device for a mobile inductive charging device of such a system, and for a stationary inductive charging device of such a system, which embodiment in particular eliminates the disadvantages of the prior art. In particular, the present invention is directed to the object of providing an improved or at least different embodiment for the method, for the computer program product, for the system, for the mobile application device, and for the stationary inductive charging device, which embodiment is distinguished by an increased accuracy and / or an increased robustness of the detection of the relative position of the power coils of the system.

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

[0009] The invention is therefore based on the following general idea: in order to identify the relative position between two energy coils, two mutually distinguishable and fixed fields are generated for one of the energy coils, which fields are received at a fixed position relative to the other energy coil, wherein the relative position of the two energy coils relative to each other is identified based on the ratio between the received fields. Since the fields are arranged fixedly relative to one energy coil on the one hand and received at a fixed position relative to the other energy coil on the other hand, the ratio changes depending on the relative position of the energy coils relative to each other. Therefore, the energy coils are arranged in an overlapping manner, for example, at a predetermined ratio of the fields relative to each other. In this way, the relative position of the energy coils and in particular the overlapping arrangement of the energy coils relative to each other can be determined in a simple and effective manner. Since the relative position of the energy coils relative to each other is identified by taking into account the ratio of the fields, a reliable and simple determination of the relative position is provided, in particular compared to the determination of the absolute value of the field or the absolute value of the difference in the running time of at least one field known from the prior art. This is due in particular to the fact that the ratio of the received fields does not change or only changes slightly when the spacing changes in the height direction. Thus, for example, a mobile inductive charging device can be installed or arranged at different heights in an associated application and / or a stationary inductive charging device can be installed or arranged at different heights or depths, and the relative position of the power coils with respect to one another can still be detected without further calibration.

[0010] As mentioned above, taking the ratio into account to identify the relative position of the energy coils relative to one another has the advantage, in particular, that repeated calibration of the inductive charging devices that transmit energy inductively to one another can be omitted. That is, at least one ratio can be specified in advance, wherein when such a ratio is determined from the received field, it is recognized that the corresponding relative position of the energy coils relative to one another exists. In this way, it is particularly possible to either transmit the specified ratio once from the inductive charging device that generates the field, preferably before the start of positioning, to the receiving inductive charging device in order to determine the relative position of the energy coils relative to one another. Alternatively and preferably, the ratio is fixedly specified so that the specified ratio is stored in the receiving inductive charging device and therefore does not need to be transmitted to the receiving inductive charging device. This makes it possible, in particular, to determine the relative position between the energy coils of different stationary inductive charging devices and different mobile inductive charging devices in a simple and robust manner without prior calibration.

[0011] According to the present invention, a method for identifying the relative position of a stationary inductive charging device relative to a mobile inductive charging device is used, wherein the stationary inductive charging device has a stationary energy coil and the mobile inductive charging device has a mobile energy coil. In charging operation, the energy coils are spaced apart from each other in the height direction. In charging operation, one of the energy coils generates an alternating magnetic field, which induces a voltage in the other energy coil for energy transmission. Here, in charging operation, the energy coils are spaced apart from each other in the height direction. In order to identify the relative position of the energy coils relative to each other, at least two fields are generated in one of the inductive charging devices, which are also referred to as positioning fields below. The positioning fields are generated in this way so that the positioning fields can be distinguished from each other, and the energy coil of the assigned inductive charging device (i.e., the inductive charging device that generates the positioning field) is fixedly positioned relative to the positioning field. In addition, the positioning field is generated in this way so that the energy coil is at least partially located in a virtual frame volume, which is bounded by at least two intensity maxima of at least two positioning fields in the positioning field and extends in the height direction. The positioning field is received at least one position fixed relative to the energy coil of the other inductive charging device. For the local ratio between at least two approach fields in the approach field, a ratio range is predefined. The predefined ratio range is such that the energy coil of the inductive charging device receiving the positioning field is arranged in the frame volume. That is to say, a ratio range of at least two positioning fields in the received positioning field is predefined, for which the energy coil of the inductive charging device receiving the positioning field is arranged in the frame volume. In order to identify the relative positions of the energy coils relative to each other, the ratio between at least two positioning fields in the received positioning field is determined. Here, if at least one of the at least one ratio determined is within the assigned, predefined ratio range, it is identified that the energy coils are arranged in the frame volume and overlap transversely to the height direction.

[0012] Advantageously, the relative positions of the power coils with respect to one another are detected by comparing the at least one ratio determined with an associated ratio range.

[0013] Preferably, at least one ratio range is stored. This simplifies the execution of the method.

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

[0015] The positioning can include the approach of the energy coils to each other and the exact positioning of the energy coils relative to each other, which positioning is also referred to as near-field positioning in the following text. In this case, the positioning device described at present is preferably used for near-field positioning. In this case, if the spacing of the energy coils relative to each other is less than 1.0 m, preferably less than 0.5 m, near-field positioning is advantageously used in order to accurately position the energy coils relative to each other. In order to bring the energy coils into proximity with each other, at least one proximity field can be used.

[0016] Preferably, the corresponding power coil has at least one winding. In the context of the invention, the extension of the power coil is understood to mean in particular the total surface area spanned by the at least one winding. In other words, in the case of a flat coil, a central region in which no winding can be present also belongs to the power coil.

[0017] In the case of an inductive charging device that generates a localization field, the localization field can be generated in any desired manner.

[0018] Advantageously, at least one of the localization fields, preferably the respective localization field, is a magnetic field and / or an electromagnetic field.

[0019] Preferably, at least one of the positioning fields, preferably the corresponding positioning field, is a magnetic field. That is to say, at least one of the positioning fields, preferably the corresponding positioning field, is generated as a positioning magnetic field. Compared with the positioning electromagnetic field, the positioning magnetic field has the following advantages: the receiver receives the positioning field in a simplified and reliable manner. In addition, it is possible to omit calibration in this way, for example, to omit calibration in terms of operating time difference as it is usually required in the case of electromagnetic fields and / or acoustic fields. Therefore, a simplified and robust determination of the ratio and thus relative position of the energy coils relative to each other is achieved by means of the positioning magnetic field. In addition, in particular, the calibration performed in the case of corresponding positioning is omitted, resulting in that positioning between different inductive charging devices can be performed. In other words, the use of the positioning magnetic field allows positioning to be implemented by means of different inductive charging devices in a simple manner.

[0020] Preferably, the main axis of the corresponding positioning field extends along the height direction. That is, the corresponding positioning field propagates at least mainly in the height direction or along the height direction, and therefore can only be received locally in the area of ​​the assigned transmitting coil and energy coil, that is, basically in the direct environment of the energy coil or in the transverse direction to the height direction. Therefore, with the help of the positioning field, the relative position is determined locally and therefore close to the fixed inductive charging device, that is, when the mobile inductive charging device is already close to the fixed inductive charging device. This type of main axis has the following advantages on the one hand: the relative position is determined more accurately, especially because the corresponding volume is more accurately defined. On the other hand, in this way, the overlap between the positioning fields of adjacent inductive charging devices, such as adjacent fixed inductive charging devices, is prevented or at least reduced transverse to the height direction. The latter leads to a more accurate determination of the relative position and a simplified, interference-reduced and reliable operation of multiple adjacent inductive charging devices, such as adjacent fixed inductive charging devices.

[0021] Advantageously, a coil is provided for the respective localization field, which coil is also referred to below as a transmitting coil. Therefore, an inductive charging device that generates at least two localization fields preferably has at least two transmitting coils, ie, has an associated transmitting coil for the respective localization field.

[0022] Advantageously, the main axis of the localization field extending in the height direction is realized by the associated transmission coil being wound around a winding axis extending parallel or substantially parallel to the height direction. That is, the transmission coil has at least one conductor path through which current flows during operation, which conductor path is wound around a winding axis extending parallel or substantially parallel to the height direction.

[0023] At least one of the transmitting coils may be a power coil of an associated inductive charging device.

[0024] The transmitting coil is preferably different from the power coil of the associated inductive charging device.

[0025] A fixed position of the localization field, in particular of the intensity maximum, relative to the energy coil can be achieved in any desired manner.

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

[0027] In principle, the relative position of the power coils with respect to one another can be detected during charging operation.

[0028] Preferably, the relative position of the power coils relative to one another is detected outside of the charging operation, ie in an operating mode different from the charging operation, which is also referred to below as the positioning operation.

[0029] Advantageously, a positioning operation is used or initiated if a predetermined distance between the inductive charging devices relative to one another transversely to the height direction is less than specified.

[0030] Preferably, in this case, one of the inductive charging devices, preferably a mobile inductive charging device, emits a ping signal which is received by the other inductive charging device, wherein the positioning operation is started upon receipt of the ping signal.

[0031] The positioning operation is expediently terminated if the power coils are aligned relative to one another. If the power coils are aligned relative to one another, the charging operation can be started.

[0032] The reception of the localization field in the other inductive charging device can be realized in any desired manner.

[0033] Advantageously, the inductive charging device that receives the localization field has at least one receiver that is fixed relative to the associated power coil and that interacts with the localization field of the other inductive charging device.

[0034] In particular, it is conceivable that the inductive charging device has a single such receiver.

[0035] In principle, the respective at least one receiver can be designed in any desired manner.

[0036] For example, at least one of the at least one receiver may be a coil, which is also referred to as a receiving coil in the following text. It is conceivable that at least one of the at least one receiver is such a receiving coil.

[0037] At least one of the at least one receiving coil can correspond to a power coil of an associated inductive charging device, that is, the power coil of the inductive charging device can be used as a power coil in the charging operation and can be used as a receiving coil for detecting the position, that is, in the detection operation.

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

[0039] The inductive charging device is used for inductively transmitting energy, wherein in the charging operation, one of the energy coils serves as a primary coil and the other energy coil serves as a secondary coil. In particular, energy is inductively transmitted from the stationary inductive charging device to the mobile inductive charging device. Variants are also conceivable in which the mobile inductive charging device inductively transmits energy to the stationary inductive charging device. Bidirectional transmission of energy is also conceivable.

[0040] Preferably, the mobile inductive charging device is mounted on an associated mobile application device, in particular a motor vehicle. Preferably, energy is inductively transmitted to the application device by means of the mobile inductive charging device, for example to charge a battery of the application device, in particular the motor vehicle.

[0041] In a preferred embodiment, a tolerance is permitted for at least one of the at least one ratio range. This allows, in particular, the use of the same stationary inductive charging device with mobile inductive charging devices arranged at different heights in the associated application, i.e., at different distances in the height direction. It is therefore particularly possible to achieve a reliable and robust detection of the relative position of the power coils relative to one another when using the mobile inductive charging device in motor vehicles of different heights, for example in sports cars, SUVs or trucks.

[0042] Alternatively or additionally, it is conceivable for this purpose to predetermine in each case an associated ratio range for different spacings of the power coils in the height direction during charging operation.

[0043] The following embodiment is considered to be advantageous: in which a virtual target volume extending in the height direction is defined within the frame volume in such a way that the energy coils of the inductive charging device that generates the localization field are at least partially located in the target volume. In addition, at least one of the ratio ranges is defined in such a way that the energy coils of the inductive charging device that receives the localization field are arranged in the target volume. In other words, if a ratio is determined within the ratio range assigned to the target volume, it is recognized that the energy coils overlap transversely to the height direction within the target volume. Since the target volume is smaller than the frame volume, an increased accuracy of the recognition of the relative positions of the energy coils relative to one another is achieved. In addition, it is thus possible to align the energy coils more precisely relative to one another.

[0044] In principle, the framework volume and / or the target volume can be selected arbitrarily.

[0045] The frame volume and the target volume are expediently selected in such a way that a high efficiency is achieved in the charging operation when the power coils overlap within the frame volume or the target volume.

[0046] The frame volume and / or the target volume is preferably selected such that, with an overlapping arrangement of the power coils within this volume, an efficiency of at least 90% is achieved during charging operation.

[0047] In this case, the frame volume and the target volume can each be assigned an associated ratio range. Advantageously, at least one ratio range assigned to the target volume is narrower than at least one ratio range assigned to the frame volume.

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

[0049] For example, at least one ratio range assigned to the frame volume can be a ratio range between 10:0.05 and 0.05:10.

[0050] In a preferred embodiment, at least two of the opposing intensity maxima are assigned to one direction. This makes it possible in particular to detect an overlap of the energy coils in this direction.

[0051] Accordingly, the following embodiment is preferred: in the embodiment, the positioning field is generated so that the intensity maximum parts of at least two positioning fields are arranged opposite to each other in the longitudinal direction extending transversely to the height direction, wherein these positioning fields are also referred to as longitudinal positioning fields hereinafter. In addition, for at least two longitudinal positioning fields in the longitudinal positioning field, an assigned ratio range is specified in advance, and this ratio range is also referred to as the longitudinal ratio range hereinafter. From the received positioning field, a ratio is obtained between at least two longitudinal positioning fields in the longitudinal positioning field, and this ratio is also referred to as the longitudinal ratio hereinafter. If the obtained longitudinal ratio is located within the assigned, specified longitudinal ratio range, it is recognized that the energy coils overlap in the longitudinal direction.

[0052] Accordingly, the following embodiment is preferred: in the embodiment, the positioning field is generated so that the maximum intensity parts of at least two positioning fields are arranged opposite to each other in a transverse direction extending transversely to the height direction, wherein these positioning fields are also referred to as transverse positioning fields hereinafter. In addition, for at least two transverse positioning fields in the transverse positioning field, an assigned ratio range is predefined in advance, and this ratio range is also referred to as a transverse ratio range hereinafter. From the received positioning field, a ratio is obtained between at least two transverse positioning fields in the transverse positioning field, and this ratio is also referred to as a transverse ratio hereinafter. If the obtained transverse ratio is within the assigned, specified transverse ratio range, it is recognized that the energy coils overlap in the transverse direction.

[0053] Preferably, not only at least two longitudinal localization fields but also at least two transverse localization fields are generated, wherein for the at least two longitudinal localization fields, an associated transverse ratio range is predefined, and for the at least two transverse localization fields, an associated transverse ratio range is predefined, and wherein at least one longitudinal ratio and at least one transverse ratio are determined from the received localization fields. This leads to an increased accuracy in the identification of the relative positions of the energy coils with respect to one another.

[0054] Accordingly, an overlap of the energy coils is preferably detected if the ascertained longitudinal ratio lies within an associated, predetermined longitudinal ratio range and if the ascertained lateral ratio lies within an associated, predetermined lateral ratio range.

[0055] Suitably, the longitudinal direction and the transverse direction extend at an angle relative to each other. Advantageously, the longitudinal direction and the transverse direction extend at least obliquely relative to each other.

[0056] Preferably, the longitudinal direction and the transverse direction extend transversely relative to each other. This allows a simplified identification of the relative position of the energy coils relative to each other. In addition, in this way, an overlapping arrangement of the energy coils can be achieved by a relative movement of the inductive charging devices relative to each other.

[0057] In this case, preferably when the mobile inductive charging device is used in a motor vehicle, the longitudinal direction corresponds to the X direction of the motor vehicle and the transverse direction corresponds to the Y direction, or vice versa.

[0058] It is conceivable that the longitudinal positioning field is generated in the stationary inductive charging device and is received in the mobile inductive charging device, and that the transverse positioning field is generated in the mobile inductive charging device and is received in the stationary inductive charging device, or vice versa.

[0059] In a preferred embodiment, all localization fields are generated in one inductive charging device and all localization fields are received in another inductive charging device. This results in a simplified execution of the method.

[0060] The following embodiment is considered to be preferred: in which the localization field is generated in such a way that two pairs of intensity maxima spaced apart from each other are arranged opposite each other in the longitudinal direction and / or two pairs of intensity maxima spaced apart from each other are arranged opposite each other in the transverse direction. Thus, two ratios or assigned ratio ranges can be used in each case to detect an overlapping arrangement of the energy coils in the longitudinal direction and / or in the transverse direction. This leads to an increased accuracy in the detection of the relative position of the energy coils relative to each other.

[0061] Preferably, the positioning field is generated such that two pairs of maximum strength portions spaced apart from each other are arranged opposite each other in the longitudinal direction, and two pairs of maximum strength portions spaced apart from each other are arranged opposite each other in the transverse direction.

[0062] Advantageously, the ratio of two localization fields with opposing intensity maxima is determined, and if the deviation of the ratio is greater than a predetermined limit value, the ratio of the localization field with the lower intensity is used for identifying the relative position. Since the intensity maxima of the corresponding localization field have a local variation curve in the form of a double hump, it is avoided to use the determined ratio between the two humps to identify the relative position of the energy coils relative to each other. Thus, errors in identifying the relative position of the energy coils relative to each other are prevented or at least reduced.

[0063] Advantageously, the ratio of two localization fields with opposing intensity maxima is determined and, if the ratios match within a specified value range, the two ratios are averaged for identifying the relative position. This results in increased accuracy and robustness in identifying the relative position of the energy coils.

[0064] In this context, the two ratios being identical is to be understood to mean, in particular, that the two ratios are substantially identical or lie within a predetermined center range.

[0065] Advantageously, four transmission coils are used to generate the longitudinal localization field and the transverse localization field. However, it should be understood that more than four localization fields and therefore more than four transmission coils may also be used.

[0066] Preferably, the transmitting coils are arranged in the corners of the rectangle. The localization field generated by means of the corresponding transmitting coils is therefore both a transverse localization field and a longitudinal localization field. This leads to a simplified design of the inductive charging device with the transmitting coils.

[0067] In an advantageous embodiment, when the calculated ratio deviates from the assigned ratio range toward the intensity maximum of one of the assigned positioning fields, the energy coil of the inductive charging device receiving the positioning field is identified relative to the energy coil of the inductive charging device generating the positioning field, and the energy coil is identified toward such an intensity maximum: the calculated ratio is offset toward the intensity maximum. That is, therefore, not only the offset of the energy coils relative to each other is identified, but also the direction of the offset. Therefore, in addition to the increased accuracy of the identification of the relative position of the energy coils relative to each other, the relative movement of the mobile inductive charging device relative to the fixed inductive charging device can be performed in such a way that the offset is eliminated. That is to say, in this way, a simplified corresponding navigation of the mobile inductive charging device or of the assigned application can be achieved.

[0068] Preferably, the positioning signal is output as a function of the ascertained value of at least one ascertained ratio relative to the associated ratio range.

[0069] The positioning signal can be used via an output device as an instruction to a person navigating the mobile inductive charging device or an associated application device and / or as a control signal for automated navigation of the mobile inductive charging device or an associated application device in such a way that the navigation results in the energy coils being arranged so as to overlap overall with respect to one another transversely to the height direction.

[0070] Preferably, the localization field is generated in such a way that, at a defined centered longitudinal ratio in the longitudinal ratio range, there is a centered arrangement of the energy coils in the longitudinal direction. Thus, an arrangement of the energy coils centered in the longitudinal direction and overlapping with respect to one another can be identified and / or navigation towards such an arrangement can be achieved in a simplified manner.

[0071] Alternatively or additionally, preferably additionally, the localization field is generated in such a way that, given a defined centered lateral ratio in the lateral ratio range, there is an arrangement of the energy coils centered relative to one another in the lateral direction. Thus, an arrangement of the energy coils centered relative to one another in the lateral direction, overlapping, can be identified and / or navigation towards such an arrangement can be achieved in a simplified manner.

[0072] Overall, it is thus possible to achieve an overall centered arrangement of the power coils relative to one another transversely to the height direction. This leads to increased efficiency during charging operation.

[0073] In principle, the corresponding centering ratios can be selected arbitrarily. In particular, at least one of the centering ratios can be 1:1 or substantially 1:1. Thus, a centered arrangement can be identified in a simplified manner and / or navigation towards the centered arrangement can be achieved in a simplified manner.

[0074] In a preferred embodiment, the localization field is generated in such a way that at least one of the ratio ranges, preferably the corresponding ratio range, is spaced apart from the intensity maximum portion of the assigned localization field. That is to say, the intensity maximum portion is located outside at least one of the at least one ratio range, preferably outside all ratio ranges. Since, as mentioned above, the intensity maximum portion of the corresponding localization field has a local variation curve in the form of a double hump, it is avoided to use the ratio obtained between the two humps to identify the relative position of the energy coils relative to each other. Therefore, errors in the identification of the relative position of the energy coils relative to each other are prevented or at least reduced.

[0075] In principle, at least two of the localization fields are generated with different intensity profiles.

[0076] In an advantageous embodiment, localization fields are generated with the same intensity profile. This allows operation of the inductive charging device generating the localization fields and / or simplified acquisition and / or simplified differentiation of the localization fields.

[0077] Preferably, the localization field is generated in such a way that the total intensity curve of the localization field is symmetrical with respect to the power coils of the inductive charging device generating the localization field. Based on the symmetry of the total intensity curve, the relative positions of the power coils with respect to one another can thus be identified in a simplified manner and / or navigation towards a centered arrangement can be achieved in a simplified manner.

[0078] In principle, it can be achieved in any desired manner that the localization fields are generated in such a way that they can be distinguished from one another.

[0079] In particular, it is conceivable to generate localization fields with different frequencies, so that they can be distinguished from one another.

[0080] Advantageously, the localization field is generated with a frequency in the range between 5 kHz and 150 kHz. Preferably, the localization field is generated with a frequency in the range between 110 kHz and 148.5 kHz, particularly preferably between 120 kHz and 145 kHz.

[0081] In this case, the frequencies assigned to the transmitting coils are preferably spaced as closely as possible from one another so that the required overall frequency spectrum is small. The frequencies are spaced, for example, at a distance of 5 kHz or 1 kHz or 100 Hz or 1 Hz or less.

[0082] Alternatively or additionally, it is conceivable to generate localization fields with respectively assigned duty cycles so that the localization fields can be differentiated. In other words, the localization fields are differentiated by means of so-called "load cycles". The use of load cycles results in localization fields having the same frequency or the same frequency band being able to be generated. In other words, fewer frequencies are therefore required. In addition, this leads in particular to a reduction in the influence of the localization device on nearby components.

[0083] In a preferred embodiment, a positioning field is generated in the stationary inductive charging device and received in the mobile inductive charging device. Since the relative movement of the mobile inductive charging device relative to the stationary inductive charging device is achieved in order to align the energy coils relative to each other, at least one ratio can be determined in the mobile inductive charging device and whether there is an overlap of the energy coils can be detected. Therefore, compared with the corresponding determination in the stationary inductive charging device and the transmission to the mobile inductive charging device or the associated application device, the result is present in the mobile inductive charging device or in the application device. In other words, the hysteresis in the recognition of the relative position of the energy coils relative to each other is prevented or at least reduced. This leads in particular to smooth navigation of the mobile inductive charging device or the application device having the mobile inductive charging device.

[0084] The method according to the invention can be used to detect the relative position of the energy coils relative to one another at any spacing. In particular, the method according to the invention can be used to navigate the energy coils and align the energy coils relative to one another in any spacing range.

[0085] Advantageously, the method can be used for detecting relative positions in the so-called near field, ie at a distance of less than 1.5 m, preferably less than 1.0 m, in particular less than 0.5 m, and / or for navigation.

[0086] Typically, inductive charging equipment is an integral part of the system.

[0087] Preferably, in this system, the mobile inductive charging device is mounted on an associated mobile application device, in particular a motor vehicle.

[0088] The method can be implemented by a computer program product which is designed accordingly.

[0089] Advantageously, the computer program product for identifying the relative position of the stationary inductive charging device relative to the mobile inductive charging device contains instructions that can be read out by a computer system such that the computer system carries out the method when executing the computer program product.

[0090] The computer program product is advantageously stored on a storage system having at least one non-volatile memory.

[0091] Advantageously, the computer program product comprises instructions for enabling the system to carry out the method.

[0092] It should be understood that computer program products also fall within the scope of the present invention.

[0093] In addition, it should be understood that the system also belongs to the scope of the present invention. In order to perform the method, the system can have a correspondingly configured control device.

[0094] The control device may at least partially contain the computer program product and / or at least partially have the computer system.

[0095] Furthermore, it is to be understood that mobile applications, in particular motor vehicles, of a mobile inductive charging device having such a system also fall within the scope of the present invention.

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

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

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

[0099] The accompanying drawings schematically show:

[0100] Figure 1 A highly simplified schematic diagram showing a system for inductive energy transfer,

[0101] Figure 2 A schematic diagram of the virtual volume is shown,

[0102] Figure 3 A simplified top view showing a stationary inductive charging device of the system,

[0103] Figure 4 shows a cross section of a stationary inductive charging device,

[0104] Figure 5 shows a graph with a localization field,

[0105] Figure 6 A simplified top view showing the system's transmit coil and receiver,

[0106] Figure 7 shows a graph with the localization field received by the receiver,

[0107] Figure 8 shows a graph with a further localization field received by a receiver,

[0108] Fig. 9 A flow chart for explaining the detection of the relative position of the power coils of a mobile inductive charging device and of a stationary inductive charging device is shown.

[0109] Fig.10 The figure shows a plan view of a power coil of an inductive charging device having a transmitting coil. DETAILED DESCRIPTION

[0110] exist Figure 1 The system 1 shown in a greatly simplified and circuit diagram-like manner in FIG. 1 is used for inductive energy transmission to a mobile application device 100, in particular for charging a battery 102 of the mobile application device 100. In the illustrated embodiment, the application device 100 is a motor vehicle 101. For this purpose, the system 1 has two inductive charging devices 2 that interact inductively with each other during charging operation, namely a stationary inductive charging device 2, 2a and a mobile inductive charging device 2, 2b for the application device 100. In order to carry out inductive energy transmission during charging operation, the respective inductive charging device 2 has an associated coil 3. These coils 3 are also referred to as energy coils 3 below. Therefore, 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. That is, one of the energy coils 3 serves as a primary coil 12, which generates an alternating magnetic field, which induces a voltage in the other energy coil 3, which serves as a secondary coil 13, for energy transmission. In the exemplary embodiment shown, the energy coils 3 are each designed as flat coils 7. In charging operation, the inductive charging devices 2 are spaced apart from one another in the height direction 200. In order to enable a charging operation and to achieve a high efficiency in 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 position of the energy coils 3 relative to one another is identified. Advantageously, this is done before the charging operation in order to achieve an optimal relative positioning of the energy coils 3 relative to one another and thus to achieve an increased efficiency.

[0111] In the exemplary embodiment shown, during charging operation, energy is transferred from stationary inductive charging device 2, 2a to mobile inductive charging device 2, 2b in order to charge battery 102 of motor vehicle 101. Accordingly, during charging operation, stationary power coil 3, 3a serves as primary coil 12 and mobile power coil 3, 3b serves as secondary coil 13. Figure 1As can be seen in the illustrative embodiment, mobile inductive charging device 2, 2b has a rectifier 14 connected between secondary coil 13 and battery 102 in order to convert the AC voltage induced in secondary coil 13 into a rectified voltage. In the illustrative embodiment, height direction 200 also corresponds to the Z direction of motor vehicle 101. Moreover, purely by way of example, longitudinal direction 201 and transverse direction 202 also correspond to the X direction or Y direction of motor vehicle 101.

[0112] In order to detect the relative positions of the energy coils 3 with respect to one another, at least two fields 60 are generated in one of the inductive charging devices 2, hereinafter referred to as Figure 5 60. These fields 60 are also referred to below as positioning fields 60. Positioning fields 60 are generated in such a way that they can be distinguished from one another and that power coil 3 of the associated inductive charging device 2 is fixedly positioned relative to positioning fields 60. Furthermore, positioning fields 60 are generated in such a way that power coil 3 of the associated inductive charging device 2 is at least partially located in a virtual volume 51, which is bounded by at least two intensity maxima 61 of at least two of the positioning fields 60 and extends in height direction 200, hereinafter referred to as Figure 2 The virtual volume 51 is explained in more detail below. This volume 51 is also referred to as frame volume 51. A localization field 60 is received at at least one position fixed relative to the energy coil 3 of the other inductive charging device 2. In this case, a ratio range 63 of at least two localization fields of the received localization fields 60 is predetermined (see Figure 5 ), for which ratio range the energy coil 3 of the inductive charging device 2 receiving the positioning field 60 is arranged in the frame volume 51. In order to identify the relative position of the energy coils 3 relative to one another, a ratio 62 between at least two of the received positioning fields 60 is determined. If at least one of the at least one ratio 62 determined is within an associated, specified ratio range 63, it is recognized that the energy coil 3 is arranged in the frame volume 51 and overlaps transversely to the height direction 200. In the illustrated exemplary embodiment, the corresponding positioning fields 60 generate a positioning magnetic field 60. The prior specification of the corresponding ratio range 63 is realized by a fixed specification, so that the ratio range 63 is stored and calibration is omitted.

[0113] In the exemplary embodiment shown, a corresponding localization field 60 is generated by an associated coil 5, which is also referred to below as a transmitting coil 5. In the exemplary embodiment shown, the corresponding localization field 60 is received by means of at least one receiver 6, which interacts with the localization field 60 and is designed as a coil 15 in the exemplary embodiment shown, which is referred to below as a receiving coil 15. In this case, the transmitting coil 5 and the at least one receiving coil 15 can be components of the localization device 4 of the system 1 (see Figure 1 ).

[0114] As from Figure 2 As can be seen in FIG. 1 , in the illustrated embodiment, the localization device 4 has a total of four transmitting coils 5, namely a first transmitting coil 5, 5a, a second transmitting coil 5, 5b, a third transmitting coil 5, 5c and a fourth transmitting coil 5, 5d. Therefore, a total of four localization fields 60 that can be distinguished from each other are generated, namely a first localization field 60a, a second localization field 60b, a third localization field 60c and a fourth localization field 60d (see FIG. 1 ). Figure 7 and 8 ). In addition, in the illustrated embodiment, a single receiver 6 is provided for receiving the positioning field 60. Figure 1 In the view shown, only two of the transmission coils 5 can be seen. Based on the differences between the localization fields 60 , a distinction can be made between the localization fields 60 by means of the at least one receiver 6 .

[0115] In the exemplary embodiment shown, a positioning field 60 is generated in one of the inductive charging devices 2 and received in the other inductive charging device 2. In this case, in the exemplary embodiment shown, a positioning field 60 is generated in the mobile inductive charging device 2, 2a and received in 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 exemplary embodiment shown, the transmitting coil 5 is different from the first energy coil 3, 3a. In the exemplary embodiment shown, purely by way of example, at least one receiving coil 15 is different from the second energy coil 3, 3b. For example Figure 2 As shown, the transmission coils 5 are arranged at a distance from one another, and in each case two of the transmission coils 5 are arranged opposite one another.

[0116] In the embodiment shown, the transmission coils 5 are constructed identically, i.e., are universal parts. Here, the respective transmission coils 5 are flat coils 7, which have at least one conductor path, not explicitly shown, which is wound around an associated winding axis (not shown) extending parallel to the height direction 200. Therefore, the respective localization field 60 has a main axis extending along the height direction 200, i.e., propagates at least mainly in or along the height direction 200, and can therefore only be received locally transversely to the height direction 20.

[0117] In the illustrated embodiment, the generation of the localization fields 60 that can be distinguished from each other is achieved in the following manner: the corresponding localization magnetic field 60 is generated at an assigned frequency. That is to say, the corresponding transmission coil 5 is operated at an assigned frequency so that the localization fields 60 can be distinguished from each other. Here, the frequencies are in particular in the range between 120kHz and 145kHz and are spaced apart from each other by, for example, a few Hz to a few kHz. For example, the frequencies can be separated from each other by 5kHz or 1kHz or 100Hz or less. Similarly, the distinction can be achieved by means of a load cycle.

[0118] Figure 2 A schematic illustration is shown in which only the transmitting coil 5 and the power coil 3 of the inductive charging device 2 with the transmitting coil 5 are shown, namely in the illustrated embodiment a stationary power coil 3 , 3 a of the system 1 .

[0119] In the exemplary embodiment shown, the geometrical arrangement of the localization field 60 and the transmission coils 5 is considered to be similar, and the corresponding localization field is generated by the associated transmission coils 5. Thus, for example, the localization field 60 generated by two opposite transmission coils 5 has opposite intensity maxima 61 parallel to the opposite arrangement of the transmission coils 5.

[0120] As from Figure 2 As can be seen in the figure, the transmitting coil 5 is arranged in such a way that the transmitting coil 5 delimits a virtual frame 50. Therefore, the frame 50 is a virtual surface delimited by the transmitting coil 5. Here, the virtual frame 50 defines a frame volume 51 extending from the frame 50 in the height direction 200. Here, the power coil 3 of the associated inductive charging device 2, that is, the stationary power coil 3, 3a in the illustrated embodiment, is at least partially arranged in the virtual frame volume 51. Therefore, the power coil 3 of the associated inductive charging device 2 is at least partially arranged in the frame 50, or is arranged offset relative to the frame 50 in the height direction 200 and is therefore arranged in the frame volume 51. In the illustrated embodiment, the transmitting coil 5 is spaced apart from the power coil 3 of the associated inductive charging device 2 and is therefore spaced apart from the stationary power coil 3, 3a in the height direction 200. Furthermore, in the illustrated embodiment, two transmitting coils of the transmitting coil 5 are arranged opposite each other in the longitudinal direction 201 and in the transverse direction 202. Transmitting coils 5 lying opposite each other in the longitudinal direction 201 are also referred to below as longitudinal transmitting coils 5, 5x, and transmitting coils 5 lying opposite each other in the transverse direction 202 are also referred to below as transverse transmitting coils 5, 5y. Accordingly, the localization fields 60 generated by the longitudinal transmitting coils 5, 5x are also referred to below as longitudinal localization fields 60, 60x with respect to one another, and the localization fields 60 generated by the transverse transmitting coils 5, 5y are also referred to below as transverse localization fields 60, 60y with respect to one another.

[0121] For example Figure 2 As shown, in the embodiment shown, the transmitting coil 5 is arranged in the corner 57 of the quadrangle 54 shaped as a rectangle 55, so that the frame 50 has the shape of the rectangle 55. Therefore, the frame volume 51 is cuboid. Figure 2 In the embodiment of the present invention, the frame 50 has the shape of a square 56. By arranging the transmitting coils 5 in the corners 57 of the rectangle 55, the corresponding transmitting coils 5 are not only the longitudinal transmitting coils 5, 5x, but also the transverse transmitting coils 5, 5y. Therefore, in the case of four transmitting coils 5, there are two pairs of transmitting coils 5 that are opposite to each other in the longitudinal direction 201 and in the transverse direction 202. Similarly, the corresponding positioning fields 60 are not only the longitudinal positioning fields 60, 60x, but also the transverse positioning fields 60, 60y. Therefore, two pairs of maximum intensity portions 61 spaced apart from each other are arranged opposite to each other in the longitudinal direction 201, and two pairs of maximum intensity portions 61 spaced apart from each other are arranged opposite to each other in the transverse direction 202.

[0122] Furthermore, it is detected based on at least one determined ratio 62 whether a power coil 3 of an inductive charging device 2 having at least one receiver 6 is located within virtual frame volume 51 and a positioning signal is outputted accordingly. In other words, in the exemplary embodiment shown, it is detected based on at least one ratio 62 whether a mobile power coil 3, 3b is located within frame volume 51 and is therefore arranged above a stationary power coil 3, 3a in height direction 200 and also at least partially overlaps the stationary power coil 3, 3a transversely to height direction 200.

[0123] As from Figure 2 As can be seen in the embodiment shown, a virtual target area 52 is defined within the frame 50. Therefore, the target area 52 is smaller than the frame 50. Here, the target area 52 defines a virtual volume 53 extending in the height direction 200 within the frame volume 51, which virtual volume is also referred to as the target volume 53 in the following and is Figure 2 In this case, the power coil 3 of the inductive charging device 2 with the transmitting coil 5, in the illustrated embodiment, the stationary power coil 3, 3a, is arranged at least partially in the target volume 53. In this case, the corresponding ratio range 63 is defined such that the power coil 3 of the inductive charging device 2 that receives the localization field 60 is arranged in the target volume 53.

[0124] The frame volume 51 and the target volume 53 are defined in such a way that a high efficiency, for example at least 90%, is achieved in the charging operation when the power coils 3 are arranged accordingly in the frame volume 51 and the target volume 53. The target volume 53 is selected in such a way that the efficiency when two power coils 3 are arranged in the target volume 53 is greater than the efficiency when two power coils 3 are arranged in the frame volume 51. Figure 3As shown, target volume 53 and thus target region 52 in the projection into height direction 200 are smaller than associated inductive charging device 2 , ie, smaller than stationary inductive charging device 2 , 2 a in the illustrated exemplary embodiment.

[0125] The positioning signal can be used to manually move the application device 100 or to autonomously move the application device 100. That is, in the embodiment of the motor vehicle 101, the positioning signal can be used to signal the vehicle leader (not shown) whether there is a desired alignment of the energy coils 3 relative to each other. For this purpose, Figure 1 As shown, motor vehicle 101 may have an output device 103 which outputs corresponding signals.

[0126] according to Figure 5 The detection of the overlap of power coils 3 is explained. Figure 5 The curves of two localization fields 60 are shown, which are generated by two transmission coils of the transmission coils 5 lying opposite each other in the longitudinal direction 201 or by two transmission coils of the transmission coils lying opposite each other in the transverse direction 202. Figure 5 In the embodiment, the positioning field 60 shown is optionally a longitudinal positioning field 60, 60x or a transverse positioning field 60, 60y. Here, in order to better distinguish, one of the positioning fields 60 is shown with a dotted line. Figure 5 The intensity profile 64 of the longitudinal localization field 60, 60x along the longitudinal direction 201 or the intensity profile of the transverse localization field 60, 60y along the transverse direction 202 is shown. Figure 5 , the localization fields 60 of the opposing transmitting coils 5 in the target volume 53 overlap. Figure 5 As can be seen in , the localization fields 60 have the same intensity profile. That is to say, the localization fields 60 are generated with the same field distribution. In addition, in the illustrated embodiment, the transmission coils 5 are designed and the localization fields 60 are generated in such a way that the total intensity profile 66 of the localization field 60 generated by the transmission coils 5 is symmetrical between the opposite transmission coils 5 and thus between the intensity maxima 61 and is symmetrical with respect to the stationary power coils 3, 3b.

[0127] As from Figure 5 As can also be seen in FIG. 6 , the corresponding localization field 60 has an intensity curve 64 with an intensity flank 65 leading to an intensity maximum 61. Figure 5 As can also be seen in FIG. 6 , the intensity maxima 61 are spaced apart from one another. Accordingly, the transmitting coil 5 is arranged and / or the localization field 60 is generated. Figure 5As can also be seen in FIG. 6 , the intensity maximum 61 of the corresponding positioning field 60 is formed in the form of a double hump. This is especially because, in the case of corresponding positioning, the receiver 6 senses the transition of the magnetic field lines (not shown). Figure 5 As shown, the corresponding ratio range 62 is arranged between successive intensity flanks 65 of the localization field 60 generated by means of the opposite, associated transmission coil 5 and is spaced apart from the intensity maximum 61. Here, for the longitudinal localization fields 60, 60x with the intensity maximums 61 opposite in the longitudinal direction 201, the associated longitudinal ratio range 63, 63x is respectively predetermined, and for the transverse localization fields 60, 60y with the intensity maximums 61 opposite in the transverse direction 202, the associated transverse ratio range 63, 63y is respectively predetermined. Here, the specified ratio range 63 is preferably stored, so that by a simple comparison between the determined ratio 62 and the associated ratio range 63, it can be detected whether there is a corresponding overlap between the energy coils 3.

[0128] That is to say, the longitudinal transmission coils 5, 5x are arranged and the longitudinal localization fields 60, 60x are generated in such a way that the intensity maximum parts 61 of the two longitudinal localization fields 60, 60x are arranged opposite each other in the longitudinal direction 201. Here, for at least two of the longitudinal localization fields 60, 60x, the assigned longitudinal ratio ranges 63, 63x are specified in advance. From the longitudinal localization fields 60, 60x received by means of the receiver 6, the longitudinal ratio 62, 62x between at least two of the longitudinal localization fields 60, 60x is determined. If the determined longitudinal ratio 62, 62x is located within the assigned prescribed longitudinal ratio range 63, 63x, it is detected that the energy coils 3 overlap in the target volume 53 in the longitudinal direction 201. Similar contents apply to the overlap in the transverse direction 202. That is to say, the transverse transmission coils 5, 5y are arranged and / or the transverse localization fields 60, 60y are generated in such a way that the intensity maxima 61 of the two transverse localization fields 60, 60y are arranged opposite each other in the transverse direction 202. In addition, for at least two of the transverse localization fields 60, 60y, an assigned transverse ratio range 63, 63y is predefined. In the localization operation, a transverse ratio 62, 62y between at least two of the transverse localization fields 60, 60y is determined from the transverse localization fields 60, 60y received by means of the receiver 6. If the determined transverse ratio 62, 62y lies within the assigned specified transverse ratio range 63, 63y, it is detected that the energy coils 3 overlap 3 in the target volume 53 in the transverse direction 202. That is, if not only at least one of the longitudinal proportions 62, 62y is located within the longitudinal proportion range 63, 63y and at least one of the transverse proportions 62, 62y is located within the transverse proportion range 63, 63y, there is an overlap of the energy coil 3 in the longitudinal direction 201 and in the transverse direction 202.

[0129] For example, a ratio range 63 between 10:0.05 and 0.05:10 can be specified for the overlap in the spatial volume 51 , and a ratio range 63 between 1:0.1 and 0.1:1 can be specified for the overlap in the target volume 53 .

[0130] Figure 6 A simplified top view of the transmission coil 5 is shown in the height direction 200 . It is assumed here that the receiver 15 moves in the longitudinal direction 201 between the first transmission coil 5 , 5 a and the second transmission coil 5 , 5 b. Figure 7 The locating fields 60 of the first transmitting coil 5 , 5 a and of the second transmitting coil 5 , 5 b which are received by the receiver 15 during the movement in the longitudinal direction 201 and thus the first locating field 60 , 60 a and the second locating field 60 , 60 b are shown. Figure 8The positioning fields 60 of the third transmitting coil 5, 5c and the fourth transmitting coil 5, 5b received by the receiver 15 when moving along the longitudinal direction 201 are shown, and thus the fourth positioning fields 60, 60c and the fourth positioning fields 60, 60d are shown. The first positioning field 60, 60a and the second positioning field 60, 60b are longitudinal positioning fields 60, 60x relative to each other. Similarly, the third positioning field 60, 60c and the fourth positioning field 60, 60d are longitudinal positioning fields 60, 60x relative to each other. Figure 7 and 8 As shown by the comparison of , the double hump shape of the localization field 60 received by the receiver 15 is more obvious for the localization field 60 close to the receiver 15 than for the localization field 60 far from the receiver 15. That is, in the described example, the double hump shape is more obvious for the received first localization field 60, 60a and the second localization field 60, 60b than for the received third localization field 60, 60c and the fourth localization field 60, 60d. Here, for easier understanding, Figure 8 60, i.e., the third and fourth localization fields 60, 60c and 60d, are not shown in the figure. Accordingly, it is advantageous to determine the ratio 62 of the two localization fields in the localization field 60 with the opposite maximum intensity portion 61, and in the case where the deviation of the ratio 62 is greater than a prescribed limit value, the ratio 62 of the localization field 60 with the lower intensity is used to identify the relative position. That is, the following localization field 60 is therefore used: the determined ratio 62 of the localization field is further away from the maximum intensity portion 61. Therefore, it is particularly prevented that the double hump shape of the maximum intensity portion 61 described above leads to an erroneous identification of the position. In contrast, if the two ratios 62 substantially correspond to each other, i.e., if the ratios 62 are substantially the same or within a prescribed value range, the two ratios 62 are averaged for identifying the relative position.

[0131] In the event of a deviation of the ascertained ratio 62 relative to the associated ratio range 63 toward an intensity maximum 61 of one of the associated localization fields 60, a displacement of the receiving power coil 3 of the inductive charging device 2 and therefore of the receiver 6 toward the intensity maximum 61 and thus toward the transmitting coil 5 generating the intensity maximum 61 is also detected: the ratio 62 is shifted toward the intensity maximum / the transmitting coil. In other words, if the ascertained longitudinal ratio 62, 62x is shifted from the associated longitudinal ratio range 63, 63x toward an intensity maximum 61 of one of the associated longitudinal localization fields 60, 60x, this means that there is a displacement of the mobile power coil 3, 3b from the target volume 53 along the longitudinal direction 201 toward the longitudinal transmitting coil 5, 5x generating the longitudinal localization field 60, 60x with the intensity maximum 61 toward which the ascertained longitudinal ratio 62, 62x is shifted. The same applies to the ascertained transverse ratios 62, 62y. That is to say, if the determined lateral ratio 62, 62y moves from the assigned lateral ratio range 63, 63y towards one of the intensity maximums 61 of one of the assigned lateral positioning fields 60, 60y, this means that there is a displacement of the mobile energy coil 3, 3b from the target volume 53 along the lateral direction 202 towards the following lateral transmitting coil 5, 5y: the lateral transmitting coil generates a lateral positioning field 60, 60y with the following intensity maximum 61: the determined lateral ratio 62, 62y moves towards this intensity maximum. Navigation of the mobile inductive charging device 2, 2a can thus be achieved in such a way that an overlap of the two energy coils 3 is achieved in the target volume and therefore not only in the longitudinal direction 201 but also in the lateral direction 202. As Figure 1 As shown, this can be achieved by means of output device 103 in order to output whether and in which direction a relative movement of mobile inductive charging device 2, 2b relative to stationary inductive charging device 2, 2a is required in order to achieve an overlap of power coils 3 in longitudinal direction 201 and in transverse direction 202. Figure 1 In the embodiment shown, purely by way of example, this is visually Figure 1 The arrows shown are displayed to achieve this. It is likewise conceivable that output device 103 outputs an acoustic signal. It is also conceivable that this result is achieved autonomously, so that motor vehicle 101 is driven autonomously in order to achieve an overlap of energy coils 3 .

[0132] The maximum efficiency in the charging operation is achieved with the corresponding relative positions of the energy coils 3 relative to one another, which are also referred to as centered arrangements in the following text. Here, the centered arrangements are each assigned a ratio 63 within the ratio range 63. That is to say, with the prescribed centered longitudinal ratios in the longitudinal ratio ranges 63, 63x, there is an arrangement of the energy coils 3 centered relative to one another in the longitudinal direction 201. Furthermore, with the prescribed centered transverse ratios in the transverse ratio ranges 63, 63y, there is an arrangement of the energy coils 3 centered relative to one another in the transverse direction 202. Therefore, if not only at least one of the determined longitudinal ratios 62, 62x corresponds to the assigned centered longitudinal ratio, but also at least one of the determined transverse ratios 62, 62y corresponds to the assigned centered transverse ratio, there is an overall centered arrangement. In the illustrated embodiment, the corresponding centering ratios are 1:1, such as Figure 5 Analogously to the explanations above, it is possible here to carry out the navigation in such a way that there is an overall centered arrangement of the energy coil 3 .

[0133] Fig. 9 A flow chart is shown for explaining the identification of the relative positions of energy coils 3 with respect to one another. If application device 100 and therefore mobile inductive charging device 2, 2b approaches stationary inductive charging device 2, 2a, a positioning operation is triggered. This is the case, for example, if the spacing of inductive charging devices 2 relative to one another transversely to 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 triggered, for example, by means of a ping signal output by mobile inductive charging device 2, 2b, upon receipt of which mobile inductive charging device 2, 2a generates a positioning field 60 with the aid of transmitting coil 5. According to Fig. 9In method measure 300 (hereinafter also referred to as receiving measure 300), a localization field 60 is received by means of a receiver 6, and in a subsequent method measure 301, the localization fields are separated from each other in such a way that the strengths of the localization fields 60 can be distinguished from each other. In this case, in method measure 301, in particular, a Fourier transformation of the signal received by means of the receiver 6 is carried out, that is, in the case of the receiving coil 15, a Fourier transformation of the voltage induced in the receiving coil 6 by means of the localization field 60. This method measure 301 is also referred to as separation measure 301 below. Therefore, the result of the separation measure 301 is an assigned value for the corresponding localization field 60, so that there are four values ​​in total. In method measure 302, the assigned longitudinal ratios 62, 62x and transverse ratios 62, 62y are respectively determined from these values ​​for the longitudinal localization fields 60, 60x and for the transverse localization fields 60, 60y. Advantageously, a plurality of values ​​are averaged in each case, for example the last ten values ​​determined, in order to increase the accuracy of the method and / or reduce the error susceptibility. This method measure 302 is also referred to below as proportional measure 302. In method measure 303, the ratio 62 determined in the proportional measure 102 is compared with a corresponding predefined proportional range 63, and based on this comparison it is determined whether there is a corresponding overlap of the energy coils 3, i.e. whether there is an arrangement of mobile energy coils 3, 3b within the target volume 53. This method measure 303 is also referred to below as comparison measure 303. Here, the comparison measure 303 outputs at least one positioning signal, such as Fig. 9 Here, the positioning signal is preferably used for navigation of the mobile application device 100, as described above. Accordingly, the positioning signal can be provided to the output device 103.

[0134] To perform relative position identification, the Figure 1 1 and 2. The control device 16 is shown simplified in FIG. 1 and is designed accordingly. The control device 16 can be a component of the locating device 4 of the system 1 or of the application device 100. In this case, the method can be implemented with the aid of a computer program product.

[0135] according to Figure 4 , an inductive charging device 2 having a transmitting coil 5, in the present case a stationary inductive charging device 2, 2a, in the illustrated embodiment has a flat coil 7 as a power coil 3, which is larger than the transmitting coil 5. Furthermore, the stationary inductive charging device 2, 2a has a flux guiding unit 8, which serves to guide the alternating field generated by the stationary power coil 3, 3a during charging operation. For this purpose, in the illustrated embodiment, the flux guiding unit 8 has a flux guiding element 9, which is designed as a ferrite plate 10. In this case, the transmitting coil 5 overlaps with the stationary power coil 3, 3a and is arranged in a rectangle 55 (see, for example Figure 2) and is arranged in a plane extending parallel to the stationary power coils 3, 3a. Furthermore, the transmitting coil 5 is arranged above the magnetic flux guidance unit 9.

[0136] Figure 4 The following shows possible relative positions of the transmitting coil 5 relative to the stationary power coil 3, 3a. Accordingly, the transmitting coil 5 can be arranged in the height direction 200 between the stationary power coil 3, 3a and the magnetic flux guiding unit 8, on the side of the magnetic flux guiding unit 8 facing away from the stationary power coil 3, 3a, or on the side of the foreign object detector 17 of the stationary inductive charging device 2, 2a facing the stationary power coil 3, 3a.

[0137] Fig.10 A further exemplary embodiment is shown which differs from the preceding exemplary embodiment in that the transmitting coil 5 is arranged offset inwards.

Claims

1. A method for identifying the relative position of a stationary inductive charging device (2, 2a) relative to a mobile inductive charging device (2, 2b), wherein: The stationary inductive charging device (2, 2a) has a stationary power coil (3, 3a), and the mobile inductive charging device (2, 2b) has a mobile power coil (3, 3b), wherein, during charging operation of the system (1), one of the power coils (3) generates an alternating magnetic field, which induces a voltage in the other power coil (3) for energy transmission, and wherein, during the charging operation, the power coils (3) are spaced apart from each other in a height direction (200), - wherein, in one of the inductive charging devices (2), at least two localization fields (60) are generated in such a way that the localization fields (60) can be distinguished from one another and that a power coil (3) of the associated inductive charging device (2) is fixedly positioned relative to the localization fields (60), and wherein the power coil (3) is located at least partially in a virtual frame volume (51) which is bounded by at least two intensity maxima (61) of at least two of the localization fields (60) and extends in a height direction (200), - wherein the positioning field (60) is received at at least one position which is fixed relative to the power coil (3) of another inductive charging device (2), - wherein a ratio range (63) of at least two of the received localization fields (60) is predetermined in advance, for which the power coil (3) of the inductive charging device (2) receiving the localization field (60) is arranged in the frame volume (51), - wherein a ratio (62) between at least two of the received localization fields (60) is determined, - if at least one of the ascertained at least one ratio (62) lies within an associated, predetermined ratio range (63), it is detected that the power coils (3) are arranged in the frame volume (51) and overlap transversely to the height direction (200).

2. The method according to claim 1, It is characterized in that - defining a virtual target volume (53) extending in the height direction (200) within the frame volume (51) such that an energy coil (3) of the inductive charging device (2) generating the localization magnetic field (60) is at least partially located in the target volume (53), At least one of the ratio ranges (63) is defined in such a way that a power coil (3) of an inductive charging device (2) which receives the localization field (60) is arranged in the target volume (53).

3. The method according to claim 1 or 2, It is characterized in that - the positioning fields (60) are generated in such a way that the intensity maxima (61) of at least two longitudinal positioning fields (60, 60x) are arranged opposite each other in a longitudinal direction (201) extending transversely to the height direction (200), - for at least two of the longitudinal localization fields (60, 60x), an associated longitudinal ratio range (63, 63x) is predefined, - determining a longitudinal ratio (62, 62x) between at least two of the longitudinal localization fields (60, 60x) from the received localization field (60), If the ascertained longitudinal ratio (62, 62x) lies within an associated, predetermined longitudinal ratio range (63, 63x), it is detected that the energy coils (3) overlap in the longitudinal direction (201).

4. The method according to any one of claims 1 to 3, It is characterized in that - the positioning fields (60) are generated in such a way that the intensity maxima (61) of at least two transverse positioning fields (60, 60y) are arranged opposite each other in a transverse direction (202) extending transversely to the height direction (200), - for at least two of the transverse positioning fields (60, 60y), an associated transverse ratio range (63, 63y) is predefined, - determining a lateral ratio (62, 62y) between at least two of the lateral ... If the ascertained lateral ratio (62, 62y) lies within an associated, predetermined lateral ratio range (63, 63y), it is detected that the energy coils (3) overlap in a lateral direction (202).

5. The method according to claims 3 and 4, It is characterized in that If the determined longitudinal ratio (62, 62x) lies within the associated, specified longitudinal ratio range (63, 63x), and If the determined transverse ratio (62, 62y) lies within the associated, specified transverse ratio range (63, 63y), It is then detected that the energy coils (3) overlap.

6. The method according to any one of claims 1 to 5, It is characterized in that The positioning field (60) is generated in such a way that two pairs of maximum strength portions (61) spaced apart from each other are arranged opposite to each other in the longitudinal direction (201) and / or two pairs of maximum strength portions (61) spaced apart from each other are arranged opposite to each other in the transverse direction (202).

7. The method according to claim 6, It is characterized in that A ratio (62) of two localization fields (60) with opposite intensity maxima (61) is determined and, if the ratios (62) deviate by more than a predetermined limit value, the ratio (62) of the localization field (60) with the lower intensity is used to identify the relative position.

8. The method according to claim 6 or 7, It is characterized in that A ratio (62) of two localization fields in a localization field (60) having opposite intensity maxima (61) is determined and, if the ratios (62) match within a value range, the two ratios (62) are averaged to identify the relative position.

9. The method according to any one of claims 1 to 8, It is characterized in that In the event that the ascertained ratio (62) deviates relative to the associated ratio range (63) towards an intensity maximum (61) of one of the associated localization fields (60), a deviation of the power coil (3) of the inductive charging device (2) receiving the localization field (60) relative to the power coil (3) of the inductive charging device (2) generating the localization field (60) towards such an intensity maximum (61) towards which the ascertained ratio (62) deviates is detected.

10. The method according to any one of claims 1 to 9, It is characterized in that A positioning signal is outputted as a function of an ascertained value of at least one ascertained ratio (62) relative to an associated ratio range (63).

11. The method according to claim 10, It is characterized in that 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 automatically navigating the mobile inductive charging device (2, 2b) for arranging the power coils (3) one above the other.

12. The method according to any one of claims 3 to 11, It is characterized in that This generates the localization field (60), - such that, in the case of a defined centered longitudinal ratio in the longitudinal ratio range (63, 63x), the energy coil (3) is arranged centered in the longitudinal direction (201), and / or - so that, given a defined centered transverse ratio in the transverse ratio range (63, 63y), the energy coils (3) are arranged centered relative to one another in the transverse direction (202).

13. The method according to any one of claims 1 to 12, It is characterized in that The localization field (60) is generated in such a way that at least one of the ratio ranges (63) is spaced apart from an intensity maximum (61) of the associated localization field (60).

14. The method according to any one of claims 1 to 13, It is characterized in that Localization fields (60) are generated with the same intensity profile (64).

15. The method according to any one of claims 1 to 14, It is characterized in that The localizing field (60) is generated in such a way that an overall intensity curve (66) of the localizing field (60) is symmetrical with respect to a power coil (3) of an inductive charging device (2) generating the localizing field (60).

16. The method according to any one of claims 1 to 15, It is characterized in that Localization fields (60) having different frequencies are generated such that the localization fields (60) can be distinguished in a receiving inductive charging device (2).

17. The method according to any one of claims 1 to 16, It is characterized in that Positioning fields (60) are generated with respectively assigned pulse duty factors, so that the positioning fields (60) can be differentiated.

18. The method according to any one of claims 1 to 17, It is characterized in that The localization field (60) is generated in the stationary inductive charging device (2, 2a) and is received in the mobile inductive charging device (2, 2b).

19. The method according to any one of claims 1 to 18, It is characterized in that The localization field (60) is generated in the mobile inductive charging device (2, 2b) and received in the stationary inductive charging device (2, 2a).

20. The method according to any one of claims 1 to 19, It is characterized in that At least one of the localization fields (60), in particular the respective localization field (60), is generated as a localization magnetic field (60).

21. The method according to any one of claims 1 to 20, It is characterized in that A corresponding positioning field (60) is generated having a main axis extending along the height direction (200). 22 . A computer program product, which is designed to carry out the method according to claim 1 .

23. A system (1) comprising a stationary inductive charging device (2, 2a) and a mobile application device (100), the mobile application device being in particular a motor vehicle (101), the mobile application device having a mobile inductive charging device (2, 2b), wherein: The stationary inductive charging device (2, 2a) has a stationary power coil (3, 3a), and the mobile inductive charging device (2, 2b) has a mobile power coil (3, 3b), wherein during charging operation, the stationary power coil and the mobile power coil are spaced apart from each other in a height direction (200) and inductively cooperate to inductively transfer energy to the application device (100), wherein one of the inductive charging devices (2) has at least two transmitting coils (5) which, in a localization mode, generate localization fields (60) which are distinguishable from one another, wherein the further inductive charging device (2) has at least one receiver (6) for receiving the positioning field (60), The system comprises a control device (12) which is designed in such a way that it operates the system (1) in the positioning mode according to the method according to any one of claims 1 to 21.

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

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

Images