Offset detection method, system and device, storage medium and computer program product

Abstract

The invention provides an offset detection method, which comprises the following steps: sampling the induced voltage of each of a plurality of ground detection coils to obtain an initial sampling voltage matrix under the condition that a vehicle-mounted marking coil is started, and arranging the plurality of ground detection coils into a detection coil matrix; correcting the initial sampling voltage matrix to obtain a correction matrix; obtaining coordinates of the vehicle-mounted beacon coil in the detection coil matrix according to the correction matrix; obtaining the coordinate of a vehicle-mounted side center point in the detection coil matrix according to the coordinate of the vehicle-mounted beacon coil in the detection coil matrix; and obtaining offset information according to the coordinates of the vehicle-mounted side center point in the detection coil matrix. The invention further provides an offset detection system, an offset detection device, a storage medium and a computer program product.

Description

Technical Field

[0001] The present disclosure relates to the field of beacon positioning technology, and in particular to an offset detection method, an offset detection system, an offset detection device, a storage medium, and a computer program product. Background Art

[0002] The electric vehicle industry has experienced rapid growth in recent years. As the EV market continues to expand, the more convenient and secure wireless power transmission (WPT) technology holds great research and application value in the automotive industry. In wireless charging systems, the primary limiting factor for output power is the alignment between the vehicle assembly (VA) power receiving coil and the ground assembly (GA) power output coil. Offset detection accuracy is a core performance characteristic of wireless charging systems, and improving it is a critical issue that needs to be addressed. Summary of the Invention

[0003] The present disclosure provides an offset detection method, an offset detection system, an offset detection device, a storage medium, and a computer program product.

[0004] In a first aspect, an embodiment of the present disclosure provides an offset detection method, comprising: sampling the induced voltage of each of a plurality of ground detection coils when a vehicle-mounted beacon coil is turned on to obtain an initial sampling voltage matrix, wherein the plurality of ground detection coils are arranged into a detection coil matrix; correcting the initial sampling voltage matrix to obtain a correction matrix; obtaining the coordinates of the vehicle-mounted beacon coil in the detection coil matrix according to the correction matrix; obtaining the coordinates of the vehicle-mounted side center point in the detection coil matrix according to the coordinates of the vehicle-mounted beacon coil in the detection coil matrix; and obtaining offset information according to the coordinates of the vehicle-mounted side center point in the detection coil matrix.

[0005] In a second aspect, an embodiment of the present disclosure provides an offset detection system, comprising: a signal generating device, comprising a vehicle-mounted beacon coil; a signal collecting device, comprising a plurality of ground detection coils arranged in a detection coil matrix; a data acquisition and processing device; and a main control and computing device, wherein the main control and computing device is constructed as follows: after the vehicle-mounted beacon coil is turned on, controlling the data acquisition and processing device to sample the induced voltage of each of the plurality of ground detection coils to obtain an initial sampling voltage matrix; correcting the initial sampling voltage matrix to obtain a correction matrix; obtaining the coordinates of the vehicle-mounted beacon coil in the detection coil matrix according to the correction matrix; obtaining the coordinates of the vehicle-mounted side center point in the detection coil matrix according to the coordinates of the vehicle-mounted beacon coil in the detection coil matrix; and obtaining offset information according to the coordinates of the vehicle-mounted side center point in the detection coil matrix.

[0006] In a third aspect, an embodiment of the present disclosure provides an offset detection device, comprising: a memory and a processor, wherein the memory stores a computer program, and the processor implements the offset detection method according to the present disclosure when executing the computer program.

[0007] In a fourth aspect, an embodiment of the present disclosure provides a storage medium having a computer program stored thereon, wherein the computer program implements the offset detection method according to the present disclosure when executed by a processor.

[0008] In a fifth aspect, an embodiment of the present disclosure provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, it implements the offset detection method according to the present disclosure.

[0009] According to an embodiment of the present disclosure, when the vehicle-mounted beacon coil is turned on, the induced voltage of each of the multiple ground detection coils is sampled to obtain an initial sampled voltage matrix, wherein the multiple ground detection coils are arranged into a detection coil matrix; the initial sampled voltage matrix is ​​corrected to obtain a correction matrix; the coordinates of the vehicle-mounted beacon coil in the detection coil matrix are obtained based on the correction matrix; the coordinates of the vehicle-mounted center point in the detection coil matrix are obtained based on the coordinates of the vehicle-mounted beacon coil in the detection coil matrix; and offset information is obtained based on the coordinates of the vehicle-mounted center point in the detection coil matrix. This overcomes the problem that the induced voltage of the ground-side detection coil of the wireless charging system is susceptible to interference from a complex electromagnetic environment during alignment detection, solves the problems of insufficient positioning accuracy and small detection range of traditional solutions, and achieves high-precision offset detection, thereby enabling the vehicle to be accurately guided to the area with maximum charging efficiency, greatly improving the reliability of the wireless charging system. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In the accompanying drawings of the embodiments of the present disclosure:

[0011] Figure 1 The following schematically illustrates the interaction between the vehicle-mounted side and the ground side according to an embodiment of the present disclosure;

[0012] Figure 2 Schematically shows a structural diagram of an offset detection system according to an embodiment of the present disclosure;

[0013] Figure 3 shows a connection diagram of a vehicle-mounted beacon coil according to an embodiment of the present disclosure;

[0014] Figure 4 A flow chart of an offset detection method according to an embodiment of the present disclosure is shown;

[0015] Figure 5 shows a schematic diagram of an induced voltage detection circuit according to an embodiment of the present disclosure;

[0016] Figure 6 A schematic diagram illustrating a method for determining a noise matrix according to an embodiment of the present disclosure is shown;

[0017] Figure 7 shows a beacon position matrix corresponding to the vehicle-mounted beacon coil according to an embodiment of the present disclosure;

[0018] Figure 8 Examples of one beacon, two beacons, and four beacons according to embodiments of the present disclosure are shown;

[0019] Figure 9 An example of clipping a beacon position matrix according to a transition region according to an embodiment of the present disclosure is shown;

[0020] Figure 10 An example of performing a subtraction operation according to an embodiment of the present disclosure is shown;

[0021] Figure 11 An example of edge area compensation operation according to an embodiment of the present disclosure is shown;

[0022] Figure 12 A block diagram of an offset detection system according to an embodiment of the present disclosure is shown;

[0023] Figure 13 A block diagram showing a composition of an offset detection device according to an embodiment of the present disclosure is shown; and

[0024] Figure 14 A block diagram showing the composition of a computer-readable medium according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical solutions of the present disclosure, the embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0026] The present disclosure will be described more fully hereinafter with reference to the accompanying drawings, but the illustrated embodiments may be embodied in different forms, and the present disclosure should not be construed as limited to the embodiments set forth below. On the contrary, these embodiments are provided so that the present disclosure will be thorough and complete and will fully understand the scope of the present disclosure to those skilled in the art.

[0027] The accompanying drawings of the embodiments of the present disclosure are used to provide a further understanding of the embodiments of the present disclosure and constitute a part of the specification. Together with the detailed embodiments, they are used to explain the present disclosure and do not constitute a limitation of the present disclosure. The above and other features and advantages will become more apparent to those skilled in the art by describing the detailed embodiments with reference to the accompanying drawings.

[0028] The present disclosure may be described with reference to plan views and / or cross-sectional views by way of ideal schematic views of the present disclosure. Therefore, the exemplary illustrations may be modified according to manufacturing techniques and / or tolerances.

[0029] In the absence of conflict, the various embodiments of the present disclosure and the various features therein may be combined with each other.

[0030] The terms used in this disclosure are only used to describe specific embodiments and are not intended to limit the disclosure. As used in this disclosure, the term "and / or" includes any and all combinations of one or more related enumerated items. As used in this disclosure, the singular forms "a" and "the" are also intended to include plural forms, unless the context clearly indicates otherwise. As used in this disclosure, the terms "comprising" and "made of" specify the presence of the features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof.

[0031] Unless otherwise defined, all terms (including technical and scientific terms) used in this disclosure have the same meanings as those commonly understood by those skilled in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this disclosure, and will not be interpreted as having an idealized or overly formal meaning unless expressly defined in this disclosure.

[0032] The present disclosure is not limited to the embodiments shown in the drawings, but includes modifications of the configurations formed based on the manufacturing process. Therefore, the regions illustrated in the drawings have schematic properties, and the shapes of the regions shown in the drawings illustrate the specific shapes of the regions of the elements, but are not intended to be limiting.

[0033] In wireless charging systems, the biggest limiting factor for output power is the alignment between the vehicle-side power receiving coil and the ground-side power output coil. For the alignment guidance between these two parts, the existing technology has proposed a visual solution that is costly and easily affected by the environment, but it is difficult to promote and apply on a large scale. In addition, a solution has been proposed to use the ground-side detection coil to align the induced voltage generated by the magnetic field change passing through it, that is, a magnetic field is generated by a ground excitation source, and a skew vibration is generated after the metal (vehicle) enters the ground-side detection coil, and the alignment is judged based on the induced voltage change generated. However, the accuracy of this solution is poor, and there is a risk of failure when the vehicle completely covers and blocks the ground coil, making it difficult to meet the system's alignment accuracy requirements.

[0034] The proposed solution to this problem is to use the alternating current between the vehicle-mounted beacon coils to generate a high-frequency magnetic field, and the ground-mounted detection coils to locate the vehicle-mounted beacon using the induced voltage through electromagnetic induction. However, due to the small number of onboard beacon coils, offset detection is performed using only the induced voltage generated by the few ground detection coils covered by the onboard beacon coil's magnetic field. This not only fails to confirm the vehicle's direction of travel, but for wireless charging systems requiring millimeter-level precision, the unfiltered DC amplitude signal is more susceptible to interference from complex electromagnetic environments, resulting in abnormal induced voltage. As a result, the calculation of positioning accuracy and yaw angle will be subject to significant errors, and calculations can only be performed for the center of the area covered by the ground coils.

[0035] From the above analysis, it can be seen that the offset detection accuracy is the core indicator of the wireless charging system. To improve the offset detection accuracy, it is necessary to solve many problems such as interference from complex electromagnetic environments and large positioning errors. The present disclosure proposes an offset detection method and an offset detection system for a wireless charging system. The offset detection system includes a signal generating device composed of a beacon coil (excitation source) on the vehicle side, a signal collecting device composed of a detection coil on the ground side, a data acquisition and processing device, and a main control and computing device. It can meet the requirements of high-precision (for example, ±10mm) alignment detection, can greatly improve the system output power when electric vehicles are wirelessly charged, and enhance product competitiveness.

[0036] Figure 1 The diagram schematically shows the interaction between the vehicle-mounted side and the ground side according to an embodiment of the present disclosure.

[0037] like Figure 1 As shown, a power receiving coil is installed on the vehicle, and four vehicle-mounted beacon coils are arranged outside the power receiving coil. Figure 1It is also shown that a charging area is set up on the ground, and a power output coil is set up in the charging area. In addition, a detection coil matrix is ​​also set up on the ground, which includes multiple ground detection coils for detecting the position of the beacon coil on the vehicle side, and then obtaining the position of the power receiving coil between the vehicle-mounted beacon coils (for example, the center point position on the vehicle side). It should be recognized that Figure 1 The vehicle-mounted side and the ground side are shown for illustrative purposes only and are not drawn to scale.

[0038] When the vehicle enters the charging area, the vehicle-mounted side establishes a wireless communication connection with the ground side. For example, the vehicle-mounted side and the ground side can establish a WIFI connection. The ground side can act as a WIFI access point device (WIFI-AP) and the vehicle-mounted side can act as a WIFI station (WIFI-STA). The controller on the ground side (not in Figure 1 (shown in the figure) can wirelessly send instructions to the vehicle-mounted side to turn on the beacon coil on the vehicle-mounted side. Subsequently, the ground detection coil receives the high-frequency magnetic field emitted by the vehicle-mounted excitation source through the LCC resonance, and generates an induced voltage of corresponding intensity. Then, the induced voltage of each ground detection coil in the detection coil matrix on the ground side is sampled, and the generated induced voltage is transmitted to the data acquisition and processing device. Finally, all the data is calculated through the digital signal processor (DSP) chip to obtain the position of the beacon coil on the vehicle-mounted side, and then the position of the power receiving coil on the vehicle-mounted side is calculated. When it is determined that the position of the power receiving coil on the vehicle-mounted side is not aligned with the power output coil on the ground side, the controller on the ground side can again send instructions to the vehicle-mounted side wirelessly to guide the vehicle to adjust its position.

[0039] Figure 2 The structure of the deviation detection system according to the embodiment of the present disclosure is schematically shown.

[0040] like Figure 2 As shown, the offset detection system according to the embodiment of the present disclosure includes a signal generating device composed of a beacon coil (excitation source) on the vehicle side, a signal collecting device composed of a detection coil on the ground side, a data acquisition and processing device (not shown), and a main control and computing device (ground controller).

[0041] exist Figure 2 The figure shows four vehicle-mounted beacon coils G10, G11, G22, and G23 located outside the power receiving coil. The subscript 1 and the cross mark 2 indicate that the vehicle-mounted beacon coils are divided into two groups G1 and G2 in the direction of the X-axis in the figure. The indexes of each vehicle-mounted beacon coil are 0 to 3, respectively. Therefore, the four vehicle-mounted beacon coils can be divided into two groups. G10 and G11 are the vehicle-mounted beacon coils of group G1, and G22 and G23 are the vehicle-mounted beacon coils of group G2. Figure 2The four vehicle-mounted beacon coils G10, G11, G22 and G23 on the vehicle side are arranged into a vehicle-mounted beacon matrix H with two rows and two columns. beacon , whose overall size is D ax *D ay (Unit: mm). The purpose of grouping the vehicle beacon coils and indexing them with numbers is to facilitate subsequent calculations. Other grouping and indexing methods are also possible and are not limited to the illustrated method. In addition, those skilled in the art should recognize that although Figure 2 Four vehicle-mounted beacon coils are shown in the figure, but other numbers of coils are also possible, as long as they can be grouped in the X-axis direction and indexed in increasing or decreasing order in the Y-axis direction.

[0042] Figure 3 A connection diagram of a vehicle-mounted beacon coil according to an embodiment of the present disclosure is shown.

[0043] like Figure 3 As shown, the four vehicle-mounted beacon coils G10, G11, G22 and G23 are each grouped into two and powered separately. Each group of beacons is connected in reverse series, that is, the positive poles of the two coils are connected with a connecting wire, and the negative poles of the two coils are connected to the power supply end respectively. Figure 3 As shown, vehicle beacon coils G10 and G22 form a group, and vehicle beacon coils G11 and G23 form another group. The positive terminals of vehicle beacon coils G10 and G22 are connected to each other, and the positive terminals of vehicle beacon coils G11 and G23 are connected to each other. The negative terminals of the four vehicle beacon coils G10, G11, G22, and G23 are all connected to the power supply. An LCC resonant circuit is formed between the power supply and the coils, ensuring that the induced voltage generated on the ground detection coil is only related to the mutual inductance current. By adjusting the resonant state, the strength of the coil excitation source signal can be controlled.

[0044] Figure 4 A flow chart of an offset detection method according to an embodiment of the present disclosure is shown.

[0045] like Figure 4 As shown, the offset detection method according to the embodiment of the present disclosure includes steps S110 to S150.

[0046] In step S110 , when the vehicle-mounted beacon coil is turned on, the induced voltage of each of the plurality of ground detection coils is sampled to obtain an initial sampled voltage matrix, wherein the plurality of ground detection coils are arranged as a detection coil matrix.

[0047] like Figure 2 As shown, multiple ground detection coils are arranged as a detection coil matrix H detection , each ground detection coil can be of size D cx *D cy(unit mm) rectangular coil, N ground detection coils are arranged into a detection coil matrix H of M1*M2 detection , where M1 and M2 are integers. Figure 2 In the example, the detection coil matrix H detection The matrix is ​​shown as 8*8, that is, M1=M2=8, but this is only an example. M1 and M2 can be set to other values ​​according to specific application scenarios, and M1 and M2 can also be set to different values.

[0048] According to an embodiment of the present disclosure, the vehicle beacon matrix H beacon The size of the ground detection coil satisfies the following relationship:

[0049]

[0050] After the vehicle enters the charging area, the vehicle side and the ground side can establish a wireless communication connection, such as a WIFI connection. The ground controller can issue a command to turn on the vehicle side excitation source (i.e., the vehicle beacon coil) and control the data acquisition and processing device to sample the induced voltage of each of the multiple ground detection coils to obtain the initial sampling voltage matrix H init At this time, the induced voltage of the ground detection coil is only related to the mutual inductance current.

[0051] Figure 5 A schematic diagram of an induced voltage detection circuit according to an embodiment of the present disclosure is shown.

[0052] like Figure 5 As shown, the ground detection coil, the supplementary capacitor and the pull-down inductor form a resonant sampling circuit, and generate an induced voltage of corresponding intensity on the ground detection coil according to the rate of change of the magnetic flux of the magnetic field projected downward by the vehicle-mounted beacon coil passing through the ground detection coil. Figure 5 It is also shown that each ground detection coil can be individually gated by a multi-way switch. Figure 5 It is shown that 64 (ie, 8*8) ground detection coils are gated by two sets of 32-way gate switches, but this is only an example and the present disclosure is not limited thereto. Figure 5In the example shown, two sets of selection switches (i.e., S1A to S32A and S1B to S32B) can be used to select two ground detection coils for data acquisition, that is, the induced voltages of the two ground detection coils can be sampled simultaneously in one sampling cycle. For example, the ground detection coils can be sampled by an external analog-to-digital converter (ADC), and Fast Fourier Transformation (FFT) processing can be performed by, for example, a Field Programmable Gate Array (FPGA) to shield the interference of electromagnetic signals of other frequencies, and obtain the induced voltage corresponding to the frequency of the vehicle excitation source. Subsequently, the data can be sent to, for example, a DSP for subsequent processing and calculation, for example, through a serial peripheral interface (SPI). Each ground detection coil can be selected in turn, and the induced voltage of each ground detection coil can be obtained to obtain the initial sampling voltage matrix H of M1*M2. init .

[0053] Back to Figure 4 In step S120, the initial sampling voltage matrix is ​​corrected to obtain a correction matrix.

[0054] According to an embodiment of the present disclosure, before sampling the induced voltage of the ground detection coil (i.e., step S110), the reference voltage of each of the plurality of ground detection coils can be detected with the vehicle-mounted beacon coil turned off to obtain a reference voltage matrix H. RV . For the initial sampling voltage matrix H init Correction (ie, step S120) includes: converting the initial sampling voltage matrix H init Subtract the reference voltage matrix H RV , to obtain the sampling voltage matrix H sample .

[0055] According to an embodiment of the present disclosure, detecting a reference voltage of each of a plurality of ground detection coils includes setting the reference voltage to the detected voltage when the detected voltage is greater than a first threshold value, or setting the reference voltage to 0 when the detected voltage is less than or equal to the first threshold value.

[0056] Without the excitation source on the vehicle, the ground controller can first perform the initialization process for alignment guidance and collect and evaluate environmental electromagnetic interference. If an induced voltage is generated in the ground detection coil without the excitation source, this induced voltage is caused by environmental electromagnetic interference.

[0057] According to the embodiment of the present disclosure, the first threshold value can be set according to the specific actual situation. For example, the first threshold value can be set to 30mV. When the excitation source is not turned on, if the induced voltage of the ground detection coil is greater than 30mV, the induced voltage is set to the reference voltage corresponding to the ground detection coil. If the induced voltage of the ground detection coil is less than or equal to 30mV, the reference voltage corresponding to the ground detection coil is set to 0. After detecting the reference voltage of each ground detection coil, the reference voltage matrix H of M1*M2 can be obtained. RV . The initial sampling voltage matrix H of M1*M2 init Subtract the reference voltage matrix H from M1*M2 RV , to obtain the sampling voltage matrix H of M1*M2 sample , that is, H sample =H init -H RV .

[0058] According to the embodiment of the present disclosure, the initial sampling voltage matrix H init The correction (ie, step S120) may further include: converting the sampled voltage matrix H sample Subtract the noise matrix H Noise , to obtain the intermediate matrix H C ; For the intermediate matrix H C Perform nonlinear transformation to obtain the correction matrix H final .

[0059] According to the embodiment of the present disclosure, the detection coil matrix H detection Perform the debugging operation to obtain the noise matrix H Noise .

[0060] Although the induced voltages of N ground detection coils have been sampled, the induced voltages generated by each ground detection coil in response to the same magnetic field change are quite different. There are two main factors that cause this phenomenon: 1) the different resonant frequencies of the corresponding resonant sampling circuits (i.e., the sampling circuits of the ground detection coils); and 2) the attenuation of the magnetic field strength due to the different air gaps (i.e., the height of the vehicle-side excitation source from the ground). The attenuation of the induced voltage of each ground detection coil is affected by its own inductance. Therefore, when the air gap reaches a certain critical value and continues to increase, the distribution pattern of the induced voltages of each ground detection coil changes, resulting in a change in the maximum induced voltage U. max The primary factor to ensure detection accuracy is to determine the coil with the largest induced voltage. The maximum induced voltage U max Misjudgment can lead to huge errors.

[0061] When the vehicle-mounted excitation source is turned on, as the air gap increases from low to high, that is, the distance D between the vehicle-mounted excitation source and the groundAB The induced voltage of the ground detection coil decreases as it moves from near to far. The following formula will clearly understand the air gap (i.e., distance D AB ) affects the induced voltage of the ground detection coil.

[0062]

[0063] Among them, U A is the induced electromotive force of the ground detection coil A, N is the number of turns of the ground detection coil, dφ A / dt is the rate of change of magnetic flux of coil A, M AB is the mutual inductance between the vehicle beacon coil B and the ground detection coil A, dI B / dt is the rate of change of the current of the vehicle beacon coil B, X is the coefficient of vacuum permeability, material permeability and the number of turns of the two coils, S A is the area of ​​the ground detection coil A, S B is the area of ​​the vehicle beacon coil B, D AB is the distance between the two coils.

[0064] It can be seen from the above formula that the distance D AB The induced electromotive force U of the ground detection coil A A Inversely proportional. When the air gap increases, the distance D AB When the ground detection coil increases, the induced electromotive force will decrease and the influence of the background noise will be more obvious. detection The corresponding noise matrix H Noise , to eliminate this impact.

[0065] Figure 6 A schematic diagram of a method for measuring a noise matrix according to an embodiment of the present disclosure is shown.

[0066] like Figure 6 As shown, before the vehicle enters the charging area, the detection coil matrix H detection Carry out debugging. Figure 6 Those skilled in the art will appreciate that the “vehicle positions” shown in the figure are essentially the vehicle-mounted beacon matrix H mounted on the vehicle. beacon On the ground side, the distance between adjacent ground detection coils is x in the X direction and y in the Y direction. When the vehicle center point (i.e., the vehicle beacon matrix H beacon The center point of the distance detection coil matrix H detectionWhen the distance is outside its direct influence range (i.e., outside n*x in the X direction and outside m*y in the Y direction, where n and m are real numbers), the voltage generated in the ground detection coil in the farthest area on the ground side is the background noise that interferes with positioning. For example, at vehicle position 1, the background noise of the ground detection coil with the same pattern as the rectangle shown in "Vehicle Position 1" is detected. At vehicle position 2, the background noise of the ground detection coil with the same pattern as the rectangle shown in "Vehicle Position 2" is detected. In this way, the background noise of the ground detection coils in the corresponding areas is sampled at four positions respectively, and a noise matrix H composed of M1*M2 random noise is obtained. Noise .

[0067] It should be recognized that the background noise generated by each ground detection coil is its inherent property. Therefore, the above debugging operation only needs to be performed once, or when the ground detection coil is changed as needed, instead of being performed before each vehicle charging. sample Subtract the noise matrix H of M1*M2 obtained by the debugging operation Noise , to obtain the intermediate matrix H of M1*M2 C , that is, H C =H sample -H Noise . Remove the noise matrix H Noise After that, the maximum induced voltage U caused by the increase of air gap and the decrease of strength can be greatly suppressed. max Misjudgment. Then, the intermediate matrix H C Perform nonlinear transformation to obtain the correction matrix H final .

[0068] According to the embodiment of the present disclosure, the entire intermediate matrix H can be transformed by nonlinear transformation. C The induced voltage of each ground detection coil in is amplified according to the corresponding coefficient, and can be transformed nonlinearly according to the following formula:

[0069]

[0070] Among them, M1 and M2 are the intermediate matrices H C The number of rows and columns, is the intermediate matrix H C The value of the i-th element (i∈[0,M1*M2-1]), N represents the intermediate matrix H C The mean of all elements of , is the intermediate matrix H C The minimum value of all elements of is the correction matrix H finalThe value of the i-th element of . Through the above calculation formula, the intermediate matrix H of M1*M2 can be C Transformed into the correction matrix H of M1*M2 final The induced voltage of the ground detection coil is transformed nonlinearly, and the proportional relationship between the induced voltages is further amplified to obtain the correction matrix H final , which can take into account the interference elimination in the low air gap situation and reduce the misjudgment of the vehicle beacon coil position in the high air gap situation.

[0071] At this point, the entire data sampling and preprocessing (ie, correction) process is completed. The above method can be based on the actual coil induced voltage of the ground detection coil and the control group (ie, the noise matrix H Noise ) to obtain the true induced voltage of the ground detection coil, greatly reducing the error increase caused by sampling.

[0072] A variety of different matrices are mentioned in the specification of the present disclosure. Here, a brief description of the above-mentioned matrices is given to facilitate a better understanding of the technical solutions of the present disclosure.

[0073] Detection coil matrix H detection It is a matrix composed of multiple ground detection coil entities.

[0074] Vehicle beacon matrix H beacon It is a matrix composed of vehicle-mounted beacon coil entities.

[0075] Initial sampling voltage matrix H init is the detection coil matrix H detection The corresponding matrix is ​​composed of the initial sampled induced voltages of each ground detection coil.

[0076] Reference voltage matrix H RV is the detection coil matrix H detection The corresponding matrix is ​​composed of the reference voltages of each ground detection coil.

[0077] Sampling voltage matrix H sample is the detection coil matrix H detection Correspondingly, the initial sampling voltage matrix H init With the reference voltage matrix H RV The matrix obtained by subtraction.

[0078] Noise matrix H Noise is the detection coil matrix H detection The corresponding matrix is ​​composed of the background noise of each ground detection coil.

[0079] Intermediate matrix H C is the detection coil matrix H detectionThe corresponding sampling voltage matrix H sample With the noise matrix H Noise The matrix obtained by subtraction.

[0080] Correction matrix H final is the detection coil matrix H detection Correspondingly, by the intermediate matrix H C The matrix obtained by performing nonlinear transformation.

[0081] Back to Figure 4 In step S130, the coordinates of the vehicle-mounted beacon coil in the detection coil matrix are obtained according to the correction matrix.

[0082] According to the embodiment of the present disclosure, according to the correction matrix H final Get the vehicle beacon coil in the detection coil matrix H detection The coordinates in (ie, step S130) include: final Get the beacon position matrix H corresponding to the vehicle beacon coil position ; According to the beacon position matrix H position Each ground detection coil in the detection coil matrix H detection The coordinates in , and the beacon position matrix H position Each ground detection coil in the correction matrix H final The corresponding value in the vehicle beacon coil is obtained in the detection coil matrix H detection The coordinates in .

[0083] Beacon position matrix H position is the detection coil matrix H detection The sub-matrix includes multiple ground detection coils arranged in rows and columns. Beacon position matrix H position It reflects the vehicle beacon coil in the detection coil matrix H detection The position of the vehicle beacon coil in the detection coil matrix H is calculated and used to obtain detection The coordinates in .

[0084] The positioning system in the embodiment of the present disclosure has two characteristic matrices, namely, the sampling voltage matrix H sample With the correction matrix H final , through the actual sampling voltage matrix H sample (or correction matrix H final ) can be used to calculate the beacon position matrix H to which each vehicle-mounted beacon coil belongs position (i.e., the vehicle-mounted beacon coil is in the detection coil matrix H detection The position in the ) is confirmed, and then the correction matrix H is combined final The values ​​in the beacon position matrix H positionEach element (i.e., each ground detection coil) in the detection coil matrix H detection The coordinates of the vehicle beacon coil are calculated in the detection coil matrix H detection The coordinates in .

[0085] The following is how to obtain the beacon position matrix H to which each vehicle-mounted beacon coil belongs position Provide explanation.

[0086] According to the embodiment of the present disclosure, according to the correction matrix H final Get the beacon position matrix H corresponding to the vehicle beacon coil position Includes: traversing the correction matrix H final , and the maximum value among the elements is taken as the first maximum value; the ground detection coil corresponding to the first maximum value is taken as the central element, and a predetermined number of ground detection coils around the central element together with the central element are set as the beacon position matrix H corresponding to the first maximum value. position .

[0087] As mentioned above, the beacon position matrix H position is the detection coil matrix H detection The sub-matrix includes multiple ground detection coils arranged in rows and columns. By traversing the correction matrix H final The elements in the equation are obtained with the first maximum value (which corresponds to the maximum induced voltage U max ), and with the ground detection coil as the center, together with a predetermined number of ground detection coils around it, a beacon position matrix H corresponding to the first maximum value is set. position . Maximum induced voltage U max It reflects the maximum impact of a vehicle-mounted beacon coil, that is, it reflects the vehicle-mounted beacon coil in the detection coil matrix H detection Therefore, the beacon position matrix H corresponding to the first maximum value is obtained position Essentially corresponds to the vehicle-mounted beacon coil.

[0088] According to an embodiment of the present disclosure, the vehicle beacon coil includes a plurality of vehicle beacon coils (for example, four vehicle beacon coils G10, G11, G22 and G23), and the plurality of vehicle beacon coils are arranged as a vehicle beacon matrix H. beacon , according to the correction matrix H final Get the beacon position matrix H corresponding to the vehicle beacon coil position Also included: In the correction matrix H final Remove the beacon position matrix H corresponding to the first maximum value position Then, traverse the correction matrix H final, to obtain the maximum value among the remaining elements as the second maximum value; compare the second maximum value with the first maximum value; when the second maximum value is greater than or equal to K times the first maximum value, take the ground detection coil corresponding to the second maximum value as the center element, and set a predetermined number of ground detection coils around the center element together with the center element as the beacon position matrix H corresponding to the second maximum value. position ; The second maximum value is taken as the new first maximum value, and the above steps are repeated; When the second maximum value is less than K times the first maximum value, or when a plurality of beacon position matrices H that are consistent with the number of vehicle-mounted beacon coils (for example, four) have been set position In the case of , the loop ends, wherein the second threshold ≤ K < 1.

[0089] Since the first maximum value is the correction matrix H final The maximum value of each element in the correction matrix H final The maximum value among the remaining elements after removing the first maximum value, so the second maximum value must be smaller than the first maximum value, so K<1; on the other hand, according to the embodiment of the present disclosure, the value range of the second threshold can be 0.3 to 0.9, that is, different second thresholds can be set according to different actual conditions, for example, the second threshold can be set to 0.4, 0.4≤K<1.

[0090] According to the above operation mode, if the beacon position matrix H corresponding to all multiple (for example, four) vehicle-mounted beacon coils has been found, position , or in the correction matrix H final If a second maximum value that meets the above condition (ie, the second maximum value is greater than or equal to K times the first maximum value) is not found in the remaining elements of , the above operation is terminated.

[0091] Figure 7 A beacon position matrix corresponding to vehicle-mounted beacon coils according to an embodiment of the present disclosure is shown.

[0092] See also Figure 7 , in the detection coil matrix H detection The four beacon position matrices H corresponding to the four beacon coils are found in position Each beacon position matrix H position The central element U first Indicated in the correction matrix H final (or the correction matrix H final The maximum value found in the remaining elements of U first 1 Indicated in the correction matrix H final The first maximum value found in the first first 2Indicated in the correction matrix H final Remove U first 1 And the beacon position matrix H composed of the surrounding elements position After that, the maximum value among the remaining elements is the second maximum value. And so on until U first 4 .

[0093] Although Figure 7 Lieutenant General beacon position matrix H position The matrix H is shown as 3*3, but the present disclosure is not limited thereto. The beacon position matrix H can be set according to specific circumstances. position Number of ground detection coils included.

[0094] The following is how to calculate the beacon position matrix H position Each ground detection coil in the detection coil matrix H detection The coordinates in , and the beacon position matrix H position Each ground detection coil in the correction matrix H final The corresponding value in the vehicle beacon coil is obtained in the detection coil matrix H detection The coordinates in are described.

[0095] According to an embodiment of the present disclosure, the vehicle beacon coil in the detection coil matrix H can be calculated by the following formula: detection Coordinates in:

[0096]

[0097] Among them, X i and Y i is the vehicle beacon coil i in the detection coil matrix H detection where i is the index of the vehicle beacon coil (e.g., i = 0 to 3), is the beacon position matrix H to which beacon i belongs position The ground detection coil with index k in the correction matrix H final The corresponding values ​​in M3 and M4 are the beacon position matrix H position The number of rows and columns, is the beacon position matrix H to which beacon i belongs position The center point of the ground detection coil with index k in the detection coil matrix H detection The X coordinate in is the beacon position matrix H to which beacon i belongs position The center point of the ground detection coil with index k in the detection coil matrix H detection The Y coordinate in .

[0098] exist Figure 7In the example, M3=M4=3, that is, the value range of k is 1 to 9. The above calculation formula reflects such a concept, that is, the beacon position matrix H position Each ground detection coil in the beacon position matrix H is used to calculate position The corresponding vehicle beacon coil is in the detection coil matrix H detection The coordinates in the matrix H play a certain role. The size of the role played by each ground detection coil is related to the ground detection coil in the correction matrix H final The larger the corresponding value, the greater the effect of the ground detection coil, and the smaller the corresponding value, the smaller the effect of the ground detection coil.

[0099] Back to Figure 4 In step S140, the coordinates of the vehicle-mounted center point in the detection coil matrix are obtained according to the coordinates of the vehicle-mounted beacon coil in the detection coil matrix.

[0100] After obtaining all vehicle-mounted beacon coils in the detection coil matrix H detection After the coordinates in the detection coil matrix H are obtained, the distance relationship between the vehicle-mounted beacons can be calculated based on the known distance relationship between the vehicle-mounted beacons. detection The coordinates in .

[0101] In step S150 , offset information is obtained according to the coordinates of the vehicle-mounted center point in the detection coil matrix.

[0102] For example, the detection coil matrix H detection The center point of is defined as the origin of the coordinate, the direction of vehicle travel is defined as the X axis, the direction perpendicular to the X axis is defined as the Y axis, and the center point of the vehicle side is calculated in the detection coil matrix H detection The distance from the coordinate in to the origin is the offset distance, and the center point on the vehicle side is calculated in the detection coil matrix H detection The yaw angle is calculated by the angle between the line connecting the coordinates in the image and the origin and the X-axis and Y-axis. The vehicle can then be guided to adjust its position based on the yaw information.

[0103] In practical applications, it is not possible to obtain the beacon position matrix H corresponding to all vehicle-mounted beacon coils in all cases. position For example, in the case of four vehicle-mounted beacon coils, the beacon position matrix H corresponding to the three vehicle-mounted beacon coils is found in the manner described above. position After that, in the correction matrix H final The remaining elements do not have the second maximum value that meets the judgment condition, that is, the correction matrix H finalThe values ​​of all remaining elements are less than K times the current first maximum value. Therefore, in practical applications, for the case of four vehicle-mounted beacon coils, it is possible to find the beacon position matrix H position The number is one to four. Figure 8 Examples of one beacon, two beacons, and four beacons according to an embodiment of the present disclosure are shown.

[0104] In the beacon position matrix H found position When the number of is less than the number of vehicle beacon coils, it is impossible to find the beacon position matrix H based on each position Directly calculate the center point of the vehicle side in the detection coil matrix H detection This situation can be overcome by grouping the vehicle-mounted beacon coils.

[0105] The grouping of vehicle beacon coils is actually based on the beacon position matrix H corresponding to the vehicle beacon coils. position To derive the vehicle beacon coil in the vehicle beacon matrix H beacon For example, in the aforementioned example of the present disclosure, each vehicle-mounted beacon coil is in the vehicle-mounted beacon matrix H beacon The arrangement is:

[0106]

[0107] The meaning of the subscript and index is not described here. In this case, grouping the vehicle beacon coils refers to grouping the vehicle beacon coils according to the beacon position matrix H corresponding to the vehicle beacon coils. position To deduce which of G10, G11, G22 and G23 the vehicle beacon coil belongs to.

[0108] For example, the coordinate system is established as in the above example, that is, the detection coil matrix H detection The center point is defined as the origin of the coordinate system, the direction of vehicle travel is defined as the X axis, and the direction perpendicular to the X axis is defined as the Y axis. If the beacon position matrix H corresponding to the vehicle beacon coil is position The X coordinate of the central element of is on the negative half axis of the X axis, which means that the vehicle beacon coil belongs to one of G10 and G11. If the beacon position matrix H corresponding to the vehicle beacon coil position The X coordinate of the central element of is on the positive half axis of the X axis, which means that the vehicle beacon coil belongs to one of G22 and G23. Correspondingly, if the beacon position matrix H corresponding to the vehicle beacon coil is position The Y coordinate of the central element of is on the negative half axis of the Y axis, which means that the vehicle beacon coil belongs to one of G10 and G22. If the beacon position matrix H corresponding to the vehicle beacon coil is positionIf the Y coordinate of the center element is on the positive half of the Y axis, it means that the vehicle-mounted beacon coil belongs to one of G11 and G23.

[0109] Based on the above method, it can be determined that the corresponding beacon position matrix H has been found position The vehicle beacon coil is in the vehicle beacon matrix H beacon Then, based on the position information, the missing vehicle beacon coil can be deduced in the vehicle beacon matrix H beacon For example, when only three vehicle-mounted beacon coils are found, the beacon position matrix H position In the case of , according to the above method, it can be determined that the three vehicle beacon coils are G10, G11 and G23, so the missing vehicle beacon coil is G22. Based on the above information, the three-beacon situation can be converted to a four-beacon situation (for example, Figure 8 (a) shown in the figure, and then the center point of the vehicle side is calculated in the detection coil matrix H according to the four-beacon method. detection Or, convert the three-beacon situation into two-beacon situation, and then derive the vehicle-side center point in the detection coil matrix H in the same way as the two-beacon situation. detection The coordinates in .

[0110] In the case of two beacons (i.e., only the beacon position matrix H corresponding to the two vehicle-mounted beacon coils is found position ),For example, Figure 8 As shown in (b), if the beacon position matrix H corresponding to the two vehicle-mounted beacon coils position The X coordinates of the central elements of are all on the positive half axis of the X axis, which means that the two missing vehicle-mounted beacon coils are beyond the detection range of the ground detection coil in the positive half axis direction of the X axis; if the beacon position matrix H corresponding to these two vehicle-mounted beacon coils position The X coordinates of the central elements of are all on the negative half axis of the X axis, which means that the two missing vehicle-mounted beacon coils are beyond the detection range of the ground detection coil in the negative half axis direction of the X axis; if the beacon position matrix H corresponding to these two vehicle-mounted beacon coils position The Y coordinates of the central elements of are all on the positive half axis of the Y axis, which means that the two missing vehicle-mounted beacon coils are beyond the detection range of the ground detection coil in the positive half axis direction of the Y axis; if the beacon position matrix H corresponding to these two vehicle-mounted beacon coils position The Y coordinates of the central elements of are all on the negative half of the Y axis, which means that the two missing vehicle beacon coils are beyond the detection range of the ground detection coil in the negative half direction of the Y axis. Based on the above information and combined with the known distance relationship between each vehicle beacon, it can be deduced that the center point of the vehicle side is in the detection coil matrix H detection The coordinates in .

[0111] In addition, even in the case of only one beacon (i.e., only one beacon position matrix H corresponding to the vehicle beacon coil is found position ),For example, Figure 8 As shown in (c), the vehicle-mounted beacon coil can also be used in the vehicle-mounted beacon matrix H beacon The position of the vehicle-mounted beacon is combined with the known distance relationship between each vehicle-mounted beacon to derive the center point of the vehicle-mounted side in the detection coil matrix H detection The coordinates in .

[0112] According to an embodiment of the present disclosure, based on the beacon position matrix H position Each ground detection coil in the detection coil matrix H detection The coordinates in , and the beacon position matrix H position Each ground detection coil in the correction matrix H final The corresponding value in the vehicle beacon coil is obtained in the detection coil matrix H detection Before the coordinates in the method further include: according to each beacon position matrix H position The central element in the detection coil matrix H detection The coordinates in the beacon position matrix H are obtained position The corresponding vehicle beacon coil is in the vehicle beacon matrix H beacon In addition, according to the position of the vehicle beacon coil in the detection coil matrix H detection The coordinates of the center point on the vehicle side are obtained in the detection coil matrix H detection The coordinates in (ie, step S140) include: detection The coordinates of the vehicle beacon coil in the vehicle beacon matrix H beacon The position of the center point on the vehicle side is obtained in the detection coil matrix H detection The coordinates in .

[0113] In actual applications, various situations may occur. For example, when the vehicle-mounted beacon coil is in the wiring area (or transition area) between two ground detection coils, the position of the vehicle-mounted beacon coil calculated by the above method will have an error of more than 20mm. For the requirement of accuracy of ±10mm, it is still necessary to identify the transition area and correct this part of the position.

[0114] According to an embodiment of the present disclosure, based on the beacon position matrix H position Each ground detection coil in the detection coil matrix H detection The coordinates in , and the beacon position matrix H position Each ground detection coil in the correction matrix H final The corresponding value in the vehicle beacon coil is obtained in the detection coil matrix H detectionBefore the coordinates in the method further include: determining each beacon position matrix H position Is the local second largest value in greater than L times the value of the central element, where the local second largest value is the beacon position matrix H position The maximum value other than the central element, the third threshold <L<1; in the case where the local second maximum value is greater than L times the value of the central element, the beacon position matrix H position If the central element and the element corresponding to the local second largest value are in the same row, then in the beacon position matrix H position Only the elements in the column where the central element is located and the elements in the column where the elements corresponding to the local second largest value are located are retained; if the central element and the elements corresponding to the local second largest value are in the same column, then in the beacon position matrix H position Only the elements in the row where the central element is located and the elements in the row where the element corresponding to the local second largest value is located are retained; if the central element and the element corresponding to the local second largest value are not in the same row or column, then in the beacon position matrix H position Only the elements in the row where the central element is located and the elements in the row where the element corresponding to the local second largest value is located are retained.

[0115] Refer to the following Figure 9 To explain the above situation, Figure 9 An example of clipping the beacon position matrix according to the transition region according to an embodiment of the present disclosure is shown.

[0116] Figure 9 In the example, a beacon position matrix H is shown as a 3*3 matrix position According to the beacon position matrix H position The method shows that the central element is the entire beacon position matrix H position The element with the maximum value in is denoted as U first In addition, in the beacon position matrix H position Among all the elements except the central element, there must be an element with a local second largest value, denoted as U second If U second Greater than the value U of the central element first L times, the third threshold <L <1, then it means there is a transition area, that is, in a beacon position matrix H position There are two ground detection coils for calculating the beacon position matrix H position The corresponding vehicle beacon coil is in the detection coil matrix H detection The coordinates in the matrix H play a role equivalent to each other. Therefore, the beacon position matrix H position Cropped to better highlight the role played by the two ground detection coils.

[0117] For example, when the vehicle beacon coil moves along the X direction with the vehicle, the induced voltage of the ground detection coil will increase as the vehicle beacon coil approaches, until the induced voltage reaches the maximum when the vehicle beacon coil reaches the center of the ground detection coil, and then gradually decreases as the vehicle beacon coil moves away. In this process, when the vehicle beacon coil is in the transition area of ​​the ground detection coil, the beacon position matrix H corresponding to the vehicle beacon coil is position There will be an obvious local secondary maximum value U second Towards the local maximum U first The approach phenomenon is that as the vehicle-mounted beacon coil moves from one ground detection coil to another ground detection coil, the high-density area of ​​the magnetic field projected downward by the vehicle-mounted beacon coil will cross the two ground detection coils and the blank area between them.

[0118] According to an embodiment of the present disclosure, the value range of the third threshold may be 0.7 to 0.9, that is, different third thresholds may be set according to different actual situations. For example, the third threshold may be set to 0.8, where 0.8<L<1.

[0119] like Figure 9 As shown in (a), positions ① to ④ are the most likely to have U second , and in the diagonal direction, there is a small probability of U second If U appears in the diagonal direction second When it is, it can be regarded as U appearing in the X direction. second For processing. Figure 9 As shown in (b), it exemplarily shows U second Appears in the case of position ④, in this case, in the beacon position matrix H position Only the central element (i.e., U first ) in the row and the local second largest value (i.e., U second ) corresponding to the elements in the row, that is, in the beacon position matrix H position Only the first and second row elements are retained. second Appears at position ①, in this case, in the beacon position matrix H position Only the central element (i.e., U first ) in the column and the local second largest value (i.e., U second ) The elements in the column corresponding to the element, that is, in the beacon position matrix H position Only the first and second column elements are retained. If U second Appears in the diagonal direction between position ① and position ④ (although the probability of this situation is very low), as U second It appears at position ④ for processing, which will not be described here.

[0120] Then, based on the clipped beacon position matrix H position To carry out the subsequent vehicle beacon coil in the detection coil matrix H detection The calculation of the coordinates in Figure 9 In the example shown, the subsequent beacon position matrix H position To perform calculation, that is, M3=2, M4=3.

[0121] In actual applications, there may be such a situation that, for example, the intensity of one vehicle-mounted beacon coil is too large, interfering with the positioning of other vehicle-mounted beacon coils.

[0122] According to an embodiment of the present disclosure, with the ground detection coil corresponding to the first maximum value as the central element, a predetermined number of ground detection coils around the central element are set together with the central element to form a beacon position matrix H corresponding to the first maximum value. position Afterwards, the method further includes: detecting the coil matrix H detection The beacon position matrix H position The ground detection coils of each final A subtraction operation is performed on the corresponding values ​​in , and the amount subtracted is the fourth percentage value of the first maximum value.

[0123] Refer to the following Figure 10 To explain the above situation, Figure 10 An example of performing a subtraction operation according to an embodiment of the present disclosure is shown.

[0124] Figure 10 In the example, a beacon position matrix H is shown as a 3*3 matrix position , and the detection coil matrix H is shown in a hatched manner detection The beacon position matrix H position The ground detection coils are shown in the form of hatched lines in the correction matrix H final The corresponding value in minus the first maximum value (ie, U first According to the embodiment of the present disclosure, the fourth percentage value ranges from 20% to 30%, that is, different fourth percentage values ​​can be set according to different actual situations. For example, the fourth percentage value can be set to 25%.

[0125] In the case of more obvious interference, the local maximum value (i.e., U first ) Determine the beacon position matrix H position When , the above subtraction operation can be performed, that is, the matrix H around the beacon position position The adjacent ground detection coils in the correction matrix H finalThe corresponding values ​​in are subtracted to prevent the intensity of the previous vehicle beacon coil from overflowing due to interference and interfering with the beacon position matrix H corresponding to the next vehicle beacon coil. position of confirmation.

[0126] In practical applications, there may also be such a situation, for example, the ground detection coil corresponding to the first maximum value (ie, the central element) is located in the detection coil matrix H detection When the edge of the center element is not selected according to the predetermined number of ground detection coils around the center element to form the beacon position matrix H corresponding to the first maximum value position .

[0127] According to an embodiment of the present disclosure, the central element is located in the detection coil matrix H detection In the case of the edge, according to the value of the center element and the beacon position matrix H position The difference of the local maximum value in the vehicle beacon coil in the detection coil matrix H detection The coordinates in are compensated, where the local second largest value is the beacon position matrix H position The maximum value other than the central element in .

[0128] Refer to the following Figure 11 To explain the above situation, Figure 11 An example of an edge area compensation operation according to an embodiment of the present disclosure is shown.

[0129] exist Figure 11 In the example, an 8*8 detection coil matrix H is shown. detection and the beacon position matrix H under two different cases (a) and (b) position .like Figure 11 As shown in (a), the vehicle-mounted beacon coil (for example, Figure 2 The vehicle-mounted beacon coil G11 is located in the detection coil matrix H detection The second row of , so in this case, the 3*3 beacon position matrix H can be determined position .like Figure 11 As shown in (b), the vehicle-mounted beacon coil (e.g., Figure 2 The vehicle-mounted beacon coil G11 is located in the detection coil matrix H detection The first row of , so in this case, only the 2*3 beacon position matrix H can be determined position .

[0130] exist Figure 11 In the case shown in (b), the value of the central element (i.e., U first ) and beacon position matrix H position The local second largest value in second ) of the vehicle beacon coil in the detection coil matrix Hdetection Specifically, it can be compensated by the local maximum U first and the local second maximum value U second The relative size (i.e., difference) of position A row of "virtual" ground detection coils is connected to the vehicle beacon coil in the detection coil matrix H. detection The role played by the position in the equation can be derived using the following formula:

[0131]

[0132] Among them, X i and Y i is the vehicle beacon coil i in the detection coil matrix H detection where i is the index of the vehicle beacon coil (e.g., i = 0 to 3), is the beacon position matrix H to which beacon i belongs position The ground detection coil with index k in the correction matrix H final The corresponding values ​​in M3 and M4 are the beacon position matrix H position The number of rows and columns, is the beacon position matrix H to which beacon i belongs position The center point of the ground detection coil with index k in the detection coil matrix H detection The X coordinate in is the beacon position matrix H to which beacon i belongs position The center point of the ground detection coil with index k in the detection coil matrix H detection The Y coordinate in C X is the contribution parameter, which is calculated as given in the above formula. The center point of the virtual ground detection coil in the detection coil matrix H detection The X coordinate in the detection coil matrix H can then be calculated based on the compensated X coordinate and Y coordinate. detection The coordinates in .

[0133] exist Figure 11 In the example, the virtual ground detection coils are in the 0th row before the first row. Similarly, the ground detection coils in the M1+1th row after the M1th row, or the ground detection coils in the 0th row to the left of the first row, or the ground detection coils in the M2+1th row to the right of the M2th row can also be virtualized. The corresponding calculation formulas can be obtained by referring to the above formulas, which are not listed here one by one.

[0134] According to the offset detection method of the embodiment of the present disclosure, the coordinates of the vehicle-mounted beacon coil are positioned, thereby achieving high-precision alignment guidance, and the position of the vehicle-mounted beacon coil is corrected based on the magnetic field scattering effect, including transition area correction and edge area compensation, and the positioning correction of the vehicle-mounted beacon coil when the sampling error is large is achieved. The overall solution has the significant advantages of low cost, high precision and good reliability. According to the technical solution of the present disclosure, it is possible to solve the problem that the induced voltage of the ground-side detection coil of the wireless charging system is susceptible to interference from a complex electromagnetic environment during the alignment detection process, and it is possible to solve the problem that the traditional solution has insufficient positioning accuracy and a small detection range, and achieve high-precision offset detection, so that the vehicle can be accurately guided to the area with maximum charging efficiency, greatly improving the reliability of the wireless charging system and product competitiveness.

[0135] Figure 12 A block diagram of an offset detection system according to an embodiment of the present disclosure is shown.

[0136] like Figure 12 As shown, according to an embodiment of the present disclosure, an offset detection system also includes: a signal generating device, including a vehicle-mounted beacon coil; a signal collecting device, including a plurality of ground detection coils arranged in a detection coil matrix; a data acquisition and processing device; and a main control and computing device.

[0137] The main control and computing device is constructed as follows: after the vehicle-mounted beacon coil is turned on, the data acquisition and processing device is controlled to sample the induced voltage of each of the multiple ground detection coils to obtain an initial sampling voltage matrix; the initial sampling voltage matrix is ​​corrected to obtain a correction matrix; the coordinates of the vehicle-mounted beacon coil in the detection coil matrix are obtained according to the correction matrix; the coordinates of the vehicle-mounted side center point in the detection coil matrix are obtained according to the coordinates of the vehicle-mounted beacon coil in the detection coil matrix; and the offset information is obtained according to the coordinates of the vehicle-mounted side center point in the detection coil matrix.

[0138] According to an embodiment of the present disclosure, the data acquisition and processing device may include an FPGA and an external ADC, and the main control and computing device may include a DSP and a gating chip.

[0139] The offset detection system according to the embodiment of the present disclosure is configured to implement the offset detection method according to each embodiment of the present disclosure, which will not be described in detail here.

[0140] The following is a detailed example to further illustrate the technical solution of offset detection according to the present disclosure.

[0141] Example 1

[0142] In this example, the system components are configured as follows:

[0143] There are 4 on-board beacon coils, each of which is a square with a side length of 2mm and is distributed in a rectangular shape with a spacing of 200mm between each other;

[0144] There are 64 ground detection coils, each of which is a 60mm*80mm rectangle and forms a 480mm*640mm detection coil matrix.

[0145] Ground controller: The main control chip selects DSP, which interacts with FPGA through SPI.

[0146] After establishing communication between the vehicle side and the ground side, turn on the vehicle side excitation source and perform the following steps:

[0147] Step S1: The ground side controls channel switching to traverse all 64 ground detection coils.

[0148] Step S2: The FPGA controls the external ADC through SPI to perform channel sampling, and then performs FFT to process the signal of the vehicle excitation source frequency.

[0149] Step S3: The DSP periodically pulls down the SPI chip select pin through a timing task to obtain the resonant induced voltage of the ground detection coil of the corresponding channel from the FPGA. The SPI data contains information: coil index, scaling factor, real part, and imaginary part.

[0150] Step S4: Repeat steps S1 to S3 until the DSP completes all channel switching and obtains the sampling matrix of the induced voltages of all ground detection coils through the FPGA.

[0151] Step S5: Traverse the sampling matrix to find the maximum value U max , and then the nine-square grid (ie, 3*3) matrix consisting of this coil and its adjacent coil indices is removed from the sampling matrix.

[0152] Step S6: Repeat step S5 until the nine-square grid corresponding to all vehicle-mounted beacon coils is found or until the maximum value U max The valid beacon conditions are no longer met.

[0153] Step S7: Determine the location of each vehicle-mounted beacon coil, group and sort them, and identify the vehicle-mounted beacon coils in the transition area and the edge area.

[0154] Step S8: Using the transition area positioning method, based on the local maximum value U in the nine-square grid corresponding to the vehicle beacon coil first and the local second maximum value U second The effective data of the vehicle beacon coil that needs to be corrected is intercepted in a nine-square grid, and the actual coordinates of the effective vehicle beacon coil are calculated using the nine-square grid induced voltage.

[0155] Step S9: Repeat step S8 to obtain the coordinates of the valid vehicle beacon coils, and then calculate the center point and deflection angle of the quadrilateral (four valid vehicle beacon coils) or triangle (three valid vehicle beacon coils) composed of the valid vehicle beacon coils through trigonometric functions, or calculate the coordinates of the center point only by the actual distance between the vehicle beacon coils (single / two valid vehicle beacon coils).

[0156] Example 2

[0157] Example 1 mainly introduces the alignment operation process when the vehicle beacon coil is in a transitional scenario. This example further explains the scenario where the vehicle center point is in the edge area.

[0158] This example applies to the following scenario: when a car enters or exits a charging area, the on-board beacon coil may be outside the coverage of the ground detection coils, but very close to the outermost ground detection coils, allowing radiation to induce voltage in the ground detection coils.

[0159] Step S1: The vehicle-mounted side and the ground side complete the initial interaction, and the ground side successfully collects the induced voltages of N coils.

[0160] Step S2: According to the vehicle beacon coil recognition algorithm, after suppressing the background noise, it is correctly identified that there are two valid vehicle beacon coils within the current ground detection range, and they belong to groups G1 and G2 respectively.

[0161] Step S3: According to the local maximum value U in the nine-square grid corresponding to the vehicle beacon coil first The position of the row is used to distinguish whether there is a transition area scene. If it is located in the first two rows or the last two rows, it is currently in the edge area and the process goes to step S5; if it is located in the other two rows, it is in the transition area and the process goes to step S4.

[0162] Step S4: Using the transition area positioning method, based on the local maximum value U in the nine-square grid corresponding to the vehicle beacon coil first and the local second maximum U second The effective data of the vehicle beacon coil that needs to be corrected is intercepted in a nine-square grid, and the actual coordinates of the effective vehicle beacon coil are calculated using the nine-square grid induced voltage.

[0163] Step S5: If the vehicle-mounted beacon coil moves from the inside to the ground detection coil at the edge, and the center point of the nine-square grid is inside, then the 3*3 matrix is ​​complete. At this time, the two-beacon / four-beacon positioning method can successfully calculate the offset position and complete the position detection; if the center point of the nine-square grid corresponding to the vehicle-mounted beacon coil is at the ground detection coil at the edge, go to step S6.

[0164] Step S6: At this time, the induced voltage of the ground detection coil at the edge is the largest, and the valid data in the nine-square grid is a 2*3 matrix. At this time, according to the change law of the induced voltage, as the vehicle-mounted beacon coil continues to move towards the non-detection area, a scene similar to the above-mentioned transition area compensation method will appear. According to the edge compensation method, the local second maximum value U second and the local maximum U first The actual position compensation is performed on the position contribution of the vehicle-mounted beacon coil, and then the coordinate calculation is completed using the two-beacon positioning method.

[0165] Figure 13 A block diagram of a displacement detection device according to an embodiment of the present disclosure is shown.

[0166] The offset detection device according to an embodiment of the present disclosure includes a memory 1302 and a processor 1301. The memory 1302 stores a computer program executable by the processor 1301. When the computer program is executed by the processor 1301, the offset detection method according to various embodiments of the present disclosure is implemented.

[0167] The processor 1301 is a device with data processing capabilities, including but not limited to a central processing unit (CPU); the memory 1302 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory (FLASH), etc.

[0168] In addition, the offset detection device according to the present disclosure may also include an I / O interface (read-write interface) 1303, which is connected between the processor 1301 and the memory 1302, and can realize information interaction between the memory 1302 and the processor 1301, including but not limited to a data bus (Bus), etc.

[0169] In some embodiments, the processor 1301 , the memory 1302 , and the I / O interface 1303 are connected to each other via a bus 1304 , and further connected to other components of the computing device.

[0170] Figure 14 A block diagram showing the composition of a computer-readable medium according to an embodiment of the present disclosure is shown.

[0171] like Figure 14 As shown, a computer-readable medium according to an embodiment of the present disclosure stores a computer program thereon, and when the computer program is executed by a processor, the offset detection method according to each embodiment of the present disclosure is implemented.

[0172] An embodiment of the present disclosure further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the offset detection method according to each embodiment of the present disclosure is implemented.

[0173] Those skilled in the art will appreciate that all or some of the steps, systems, and functional modules / units in the apparatus disclosed above may be implemented as software, firmware, hardware, or a suitable combination thereof.

[0174] In hardware implementations, the division between functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component may have multiple functions, or one function or step may be performed by several physical components in cooperation.

[0175] Some or all of the physical components may be implemented as software executed by a processor, such as a central processing unit (CPU), a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software may be distributed on a computer-readable medium, which may include computer storage media (or non-transitory media) and communication media (or temporary media). As is well known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory (FLASH) or other disk storage; compact disc (CD-ROM), digital versatile disc (DVD) or other optical disc storage; magnetic cassettes, tapes, disk storage or other magnetic storage; any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, as is well known to those skilled in the art, communication media typically embodies computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0176] The present disclosure has disclosed example embodiments, and although specific terms are employed, they are used and should be interpreted only in a general illustrative sense and not for purposes of limitation. In some instances, it will be apparent to those skilled in the art that, unless otherwise expressly indicated, features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in conjunction with other embodiments. Therefore, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the scope of the present disclosure as set forth in the appended claims.

Claims

1. A method for detecting an offset, comprising: When the vehicle-mounted beacon coil is turned on, sampling the induced voltage of each of the plurality of ground detection coils to obtain an initial sampling voltage matrix, wherein the plurality of ground detection coils are arranged as a detection coil matrix; Correcting the initial sampling voltage matrix to obtain a correction matrix; Obtaining the coordinates of the vehicle-mounted beacon coil in the detection coil matrix according to the correction matrix; Obtaining the coordinates of the vehicle-side center point in the detection coil matrix according to the coordinates of the vehicle-mounted beacon coil in the detection coil matrix; The offset information is obtained according to the coordinates of the vehicle-mounted center point in the detection coil matrix.

2. The offset detection method according to claim 1, wherein: Before sampling the induced voltage of each of the plurality of ground detection coils, the method further includes: When the vehicle-mounted beacon coil is turned off, a reference voltage of each of the plurality of ground detection coils is detected to obtain a reference voltage matrix. Correcting the initial sampling voltage matrix includes: The reference voltage matrix is ​​subtracted from the initial sampling voltage matrix to obtain a sampling voltage matrix.

3. The offset detection method according to claim 2, wherein: Detecting a reference voltage of each of the plurality of ground detection coils includes: If the detected voltage is greater than a first threshold, setting the reference voltage to the detected voltage; or When the detected voltage is less than or equal to the first threshold, the reference voltage is set to 0.

4. The offset detection method according to claim 2, wherein: Correcting the initial sampling voltage matrix further includes: Subtracting a noise matrix from the sampled voltage matrix to obtain an intermediate matrix; A nonlinear transformation is performed on the intermediate matrix to obtain the correction matrix.

5. The offset detection method according to claim 4, wherein: The noise matrix is ​​obtained by performing a debugging operation on the detection coil matrix. The offset detection method according to claim 1 , wherein: Obtaining the coordinates of the vehicle-mounted beacon coil in the detection coil matrix according to the correction matrix includes: Obtaining a beacon position matrix corresponding to the vehicle-mounted beacon coil according to the correction matrix; The coordinates of the vehicle-mounted beacon coil in the detection coil matrix are obtained according to the coordinates of each ground detection coil in the beacon position matrix in the detection coil matrix and the corresponding values ​​of each ground detection coil in the beacon position matrix in the correction matrix.

7. The offset detection method according to claim 6, wherein: Obtaining a beacon position matrix corresponding to the vehicle-mounted beacon coil according to the correction matrix includes: Traversing each element in the correction matrix to obtain a maximum value among the elements as a first maximum value; The ground detection coil corresponding to the first maximum value is used as a central element, and a predetermined number of ground detection coils around the central element are arranged together with the central element to form a beacon position matrix corresponding to the first maximum value.

8. The offset detection method according to claim 7, wherein: The vehicle-mounted beacon coil includes a plurality of vehicle-mounted beacon coils, and the plurality of vehicle-mounted beacon coils are arranged into a vehicle-mounted beacon matrix. Obtaining a beacon position matrix corresponding to the vehicle-mounted beacon coil according to the correction matrix further includes: After removing the beacon position matrix corresponding to the first maximum value from the correction matrix, traversing the remaining elements in the correction matrix to obtain a maximum value among the remaining elements as a second maximum value; comparing the second maximum value with the first maximum value; When the second maximum value is greater than or equal to K times the first maximum value, taking the ground detection coil corresponding to the second maximum value as a central element, and arranging a predetermined number of ground detection coils around the central element together with the central element into a beacon position matrix corresponding to the second maximum value; Taking the second maximum value as the new first maximum value, and repeating the above steps; When the second maximum value is less than K times the first maximum value, or when a number of beacon position matrices matching the number of vehicle-mounted beacon coils has been set, the loop ends, wherein the second threshold ≤ K < 1.

9. The offset detection method according to claim 8, wherein: Before obtaining the coordinates of the vehicle-mounted beacon coil in the detection coil matrix based on the coordinates of each ground detection coil in the beacon position matrix in the detection coil matrix and the corresponding values ​​of each ground detection coil in the beacon position matrix in the correction matrix, the method further includes: Obtaining, according to the coordinates of the central elements of each beacon position matrix in the detection coil matrix, the position of the vehicle-mounted beacon coil corresponding to the beacon position matrix in the vehicle-mounted beacon matrix; Obtaining the coordinates of the vehicle-side center point in the detection coil matrix according to the coordinates of the vehicle-mounted beacon coil in the detection coil matrix includes: The coordinates of the vehicle-mounted center point in the detection coil matrix are obtained according to the coordinates of the vehicle-mounted beacon coil in the detection coil matrix and the position of the vehicle-mounted beacon coil in the vehicle-mounted beacon matrix.

10. The offset detection method according to claim 8, wherein: Before obtaining the coordinates of the vehicle-mounted beacon coil in the detection coil matrix based on the coordinates of each ground detection coil in the beacon position matrix in the detection coil matrix and the corresponding values ​​of each ground detection coil in the beacon position matrix in the correction matrix, the method further includes: Determine whether the local second largest value in each of the beacon position matrices is greater than L times the value of the central element, wherein the local second largest value is the maximum value in the beacon position matrix excluding the central element, and a third threshold value <L<1; In the case where the local second maximum value is greater than L times the value of the central element, the beacon position matrix is ​​cropped. If the central element and the element corresponding to the local second maximum value are in the same row, only the elements in the column where the central element is located and the elements in the column where the element corresponding to the local second maximum value is located are retained in the beacon position matrix; if the central element and the element corresponding to the local second maximum value are in the same column, only the elements in the row where the central element is located and the elements in the row where the element corresponding to the local second maximum value is located are retained in the beacon position matrix; if the central element and the element corresponding to the local second maximum value are not in the same row or column, only the elements in the row where the central element is located and the elements in the row where the element corresponding to the local second maximum value is located are retained in the beacon position matrix.

11. The offset detection method according to claim 7, wherein: After taking the ground detection coil corresponding to the first maximum value as a central element and setting a predetermined number of ground detection coils around the central element together with the central element to form a beacon position matrix corresponding to the first maximum value, the method further includes: A subtraction operation is performed on corresponding values ​​in the correction matrix of each ground detection coil in the detection coil matrix surrounding the beacon position matrix, and the subtracted amount is a fourth percentage value of the first maximum value.

12. The offset detection method according to claim 7, wherein: When the central element is located at the edge of the detection coil matrix, the coordinates of the vehicle-mounted beacon coil in the detection coil matrix are compensated according to the difference between the value of the central element and the local second maximum value in the beacon position matrix, wherein the local second maximum value is the maximum value in the beacon position matrix other than the central element.

13. A deviation detection system comprising: A signal generating device including a vehicle-mounted beacon coil; a signal collection device comprising a plurality of ground detection coils arranged in a detection coil matrix; Data acquisition and processing device; as well as Main control and computing device, Wherein, the main control and computing device is constructed as follows: After the vehicle-mounted beacon coil is turned on, controlling the data acquisition and processing device to sample the induced voltage of each of the plurality of ground detection coils to obtain an initial sampled voltage matrix; Correcting the initial sampling voltage matrix to obtain a correction matrix; Obtaining the coordinates of the vehicle-mounted beacon coil in the detection coil matrix according to the correction matrix; Obtaining the coordinates of the vehicle-side center point in the detection coil matrix according to the coordinates of the vehicle-mounted beacon coil in the detection coil matrix; The offset information is obtained according to the coordinates of the vehicle-mounted center point in the detection coil matrix.

14. A deviation detection device comprising: A memory and a processor, wherein the memory stores a computer program, and the processor implements the method according to any one of claims 1 to 12 when executing the computer program.

15. A storage medium having a computer program stored thereon, wherein the computer program implements the method according to any one of claims 1 to 12 when executed by a processor.

16. A computer program product comprising a computer program, wherein when the computer program is executed by a processor, the method according to any one of claims 1 to 12 is implemented.

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