Vehicle position detection method and device, storage medium and vehicle

Abstract

This invention discloses a vehicle position detection method, device, storage medium, and vehicle. The method relates to the field of vehicle-to-everything (V2X) communication and includes: controlling the ground coil of a wireless charging pile to charge the vehicle and acquiring charging parameters of the vehicle during the charging process. These charging parameters include: a first input current input to the ground coil, a second input current input to the vehicle-side rectifier bridge, and the resonant network impedance designed for the vehicle-side equipment. Based on the charging parameters, the mutual inductance value between the vehicle-side coil and the ground coil of the wireless charging pile is determined. The vehicle position is then detected in real time based on the mutual inductance value to obtain a detection result, wherein the detection result indicates whether the vehicle is located within a preset charging area of ​​the wireless charging pile. This invention solves the technical problem of low accuracy in detecting mutual inductance during vehicle alignment in related technologies.

Description

Technical Field

[0001] This invention relates to the field of vehicle networking, and more specifically, to a vehicle location detection method, device, storage medium, and vehicle. Background Technology

[0002] Alignment guidance is an essential auxiliary function in wireless charging systems, and achieving interoperability between vehicle-side and ground-side devices from different manufacturers is a problem that must be solved. Therefore, achieving interoperability is key to the commercialization and widespread adoption of wireless charging technology. However, with current interoperability technologies, the accuracy of mutual inductance estimation is affected by operating frequency, coil height, and power transmission status, resulting in low accuracy in mutual inductance estimation and, consequently, low accuracy in detecting the alignment mutual inductance of parked vehicles.

[0003] There is currently no effective solution to the above problems. Summary of the Invention

[0004] This invention provides a vehicle position detection method, apparatus, storage medium, and vehicle to at least solve the technical problem of low detection accuracy of mutual inductance during vehicle alignment in related technologies.

[0005] According to one aspect of the present invention, a vehicle position detection method is provided, comprising: controlling a ground coil of a wireless charging pile to charge a vehicle, and acquiring charging parameters of the vehicle during the charging process, wherein the charging parameters include: a first input current input to the ground coil, a second input current input to the vehicle-side rectifier bridge, and the resonant network impedance designed for the vehicle-side equipment; determining the mutual inductance value between the vehicle-side coil and the ground coil of the wireless charging pile based on the charging parameters; and performing real-time detection of the vehicle position based on the mutual inductance value to obtain a detection result of the vehicle position, wherein the detection result is used to characterize whether the vehicle is located within a preset charging area of ​​the wireless charging pile.

[0006] Optionally, determining the mutual inductance value between the vehicle-side coil and the wireless charging pile ground coil based on charging parameters includes: compensating the resonant network impedance based on a first preset relationship to obtain a target impedance, wherein the first preset relationship is used to characterize the mutual inductance difference between the resonant network impedance and the target impedance at different charging frequencies; determining the vehicle-side resonant parameters at different charging frequencies based on the target impedance and a first preset coefficient; compensating the first input current based on a second preset relationship to obtain a first target current, wherein the second preset relationship is used to characterize the current difference between the first input current and the actual input current at different mutual inductance values; and determining the mutual inductance value based on the first target current, the second input current, and the resonant parameters.

[0007] Optionally, the target impedance includes: a first target impedance, a second target impedance, and a third target impedance, wherein the first target impedance is the impedance of the vehicle's first inductor, first capacitor, and second capacitor; the second target impedance is the impedance of the vehicle's second inductor and second capacitor; and the third target impedance is the impedance of the second capacitor. Based on the target impedance and a first preset coefficient, the vehicle's resonance parameters are determined, including: obtaining the product of the first target impedance and the second target impedance to obtain a first product; obtaining the square of the third target impedance to obtain a first squared value; obtaining the difference between the first product and the first squared value to obtain a first difference; obtaining the product of the third target impedance and the first preset coefficient to obtain a second product; obtaining the quotient of the first difference and the second product to obtain a first quotient; and obtaining the absolute value of the first quotient to obtain the resonance parameters.

[0008] Optionally, the mutual inductance value is determined based on the first target current, the second input current, and the resonance parameter, including: obtaining the absolute value of the first target current to obtain a first absolute value, and obtaining the absolute value of the second input current to obtain a second absolute value; obtaining the quotient of the second absolute value and the first absolute value to obtain a second quotient; and obtaining the product of the second quotient and the resonance parameter to obtain the mutual inductance value.

[0009] Optionally, obtaining the first input current includes: obtaining the DC bus voltage of the wireless charging pile and the fourth target impedance of the third capacitor; and obtaining the first input current based on the DC bus voltage, the fourth target impedance, and the second preset coefficient.

[0010] Optionally, the first input current is obtained based on the DC bus voltage, the fourth target impedance, and the second preset coefficient, including: obtaining the product of the second preset coefficient and the DC bus voltage to obtain a third product; obtaining the absolute value of the third product to obtain a third absolute value, and obtaining the absolute value of the fourth target impedance to obtain a fourth absolute value; obtaining the quotient of the third absolute value and the fourth absolute value to obtain the first input current.

[0011] Optionally, the vehicle is detected based on the mutual inductance value to obtain the vehicle detection result, including: judging the mutual inductance value based on a preset threshold to obtain a judgment result, wherein the judgment result is used to characterize whether the mutual inductance value is less than or equal to the preset threshold; in response to the judgment result that the mutual inductance value is less than or equal to the preset threshold, determining that the detection result is that the vehicle is outside the preset charging area of ​​the wireless charging pile; in response to the judgment result that the mutual inductance value is greater than the preset threshold, determining that the detection result is that the vehicle is within the preset charging area of ​​the wireless charging pile.

[0012] According to another aspect of the present invention, a vehicle position detection device is also provided, comprising: an acquisition module, configured to control the ground coil of a wireless charging pile to charge a vehicle and acquire charging parameters of the vehicle during the charging process, wherein the charging parameters include: a first input current input to the ground coil, a second input current input to the vehicle-side rectifier bridge, and the resonant network impedance designed for the vehicle-side device; a determination module, configured to determine the mutual inductance value between the vehicle-side coil and the ground coil of the wireless charging pile based on the charging parameters; and a detection module, configured to perform real-time detection of the vehicle position based on the mutual inductance value to obtain a detection result of the vehicle position, wherein the detection result is used to characterize whether the vehicle is located within a preset charging area of ​​the ground charging pile.

[0013] According to another aspect of the present invention, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored program, wherein, when the program is running, the device on which the computer-readable storage medium is located executes any of the above methods.

[0014] According to another aspect of the present invention, a vehicle is also provided, including a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform any of the methods described above.

[0015] In this embodiment of the invention, the vehicle is charged by controlling the ground coil of the wireless charging pile, and the charging parameters of the vehicle during the charging process are acquired. Based on the charging parameters, the mutual inductance value between the vehicle's vehicle-side coil and the ground coil of the wireless charging pile is determined. The vehicle position is then detected in real time based on the mutual inductance value to obtain the vehicle position detection result. It is easy to note that by acquiring the first input current, the second input current, and the resonant network impedance, the mutual inductance can be actively corrected, thereby improving the accuracy and consistency of the mutual inductance estimation. This achieves the goal of accurately detecting the mutual inductance during vehicle alignment, thus improving the technical effect of improving the detection accuracy of mutual inductance during vehicle alignment, and solving the technical problem of low detection accuracy of mutual inductance during vehicle alignment in related technologies. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0017] Figure 1 This is a flowchart of a vehicle position detection method according to an embodiment of the present invention;

[0018] Figure 2 This is a circuit diagram of an optional wireless charging system according to an embodiment of the present invention;

[0019] Figure 3 This is a calibration schematic diagram showing the variation of mutual inductance value with I_ga according to an embodiment of the present invention;

[0020] Figure 4 This is a schematic diagram of optional mutual inductance compensation calibration according to an embodiment of the present invention.

[0021] Figure 5 This is a schematic diagram of an optional compensation design according to an embodiment of the present invention;

[0022] Figure 6 This is a flowchart of an optional mutual inductance calculation method according to an embodiment of the present invention;

[0023] Figure 7 This is a schematic diagram of an optional multi-vehicle-to-multi-pile wireless charging public application scenario according to an embodiment of the present invention;

[0024] Figure 8 This is a schematic diagram of a vehicle position detection device according to an embodiment of the present invention. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0027] Example 1

[0028] According to an embodiment of the present invention, a vehicle position detection method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0029] Figure 1 This is a flowchart of a vehicle position detection method according to an embodiment of the present invention, such as... Figure 1 As shown, the method includes the following steps:

[0030] Step S102: Control the ground coil of the wireless charging pile to charge the vehicle and obtain the charging parameters of the vehicle during the charging process. The charging parameters include: the first input current input to the ground coil, the second input current input to the vehicle-side rectifier bridge, and the resonant network impedance designed for the vehicle-side equipment.

[0031] The aforementioned wireless charging pile ground coil can be a ground coil used in a ground charging pile for wirelessly charging vehicles. The wireless charging pile can be any type of ground charging pile capable of aligning with and wirelessly charging a vehicle; its specific type is not limited in this embodiment. Similarly, the aforementioned vehicle can be any type of vehicle capable of aligning with and charging via the wireless charging pile; its specific type is not limited in this embodiment.

[0032] In one optional embodiment, when the vehicle needs charging, it can first be aligned with a wireless charging station. Upon successful alignment, the vehicle can be charged via the wireless charging station's ground coil using the wireless charging system. At this time, charging parameters of the vehicle during the charging process can be obtained in the wireless charging system. These parameters may include, but are not limited to: a first input current input to the ground coil, and a second input current I input to the vehicle-side rectifier bridge. rec And the resonant network impedance of the vehicle-side equipment design. For example, this may include, but is not limited to, the impedance of the vehicle's first inductor, second inductor, first capacitor, and second capacitor.

[0033] It should be noted that the wireless charging system mentioned above can be a wireless charging system for electric vehicles in accordance with the national standard GB / T 38775. In this system, the system adopts an LCC compensation topology with double-sided series inductors, parallel capacitors and series capacitors. LCC stands for inductor-capacitor-capacitor.

[0034] Step S104: Based on the charging parameters, determine the mutual inductance value between the vehicle-side coil and the ground-side coil of the wireless charging pile.

[0035] In one optional embodiment, after obtaining the charging parameters, the mutual inductance value between the vehicle-end coil and the ground-end coil can be calculated based on the charging parameters. For example, the quotient of the first input current and the second input current can be obtained, and then the product of the quotient and the resonant network impedance can be obtained to get the mutual inductance value, but it is not limited to this. Alternatively, the product of the first input current and the resonant network impedance can be obtained to get a first product, and then the quotient of the first product and the second input current can be obtained to get the mutual inductance value.

[0036] Step S106: Real-time detection of vehicle position based on mutual inductance value to obtain vehicle position detection result, wherein the detection result is used to characterize whether the vehicle is located within the preset charging area of ​​the wireless charging pile.

[0037] The aforementioned preset charging area can be a charging area set in advance by the user to indicate whether the vehicle and the wireless charging station are accurately aligned. When the vehicle is located within the preset charging area, it indicates that the vehicle and the wireless charging station are accurately aligned.

[0038] In one optional embodiment, after obtaining the mutual inductance value, it can be compared with a preset mutual inductance value. A comparison result can be obtained where the mutual inductance value is less than or equal to the preset mutual inductance value, or where the mutual inductance value is greater than the preset mutual inductance value. When the comparison result is that the mutual inductance value is less than or equal to the preset mutual inductance value, it indicates that the vehicle is outside the preset charging area of ​​the wireless charging station, meaning the vehicle and the wireless charging station are not accurately aligned. When the comparison result is that the mutual inductance value is greater than the preset mutual inductance value, it indicates that the vehicle is within the preset charging area of ​​the wireless charging station, meaning the vehicle and the wireless charging station are accurately aligned.

[0039] In this embodiment of the invention, the vehicle is charged by controlling the ground coil of the wireless charging pile, and the charging parameters of the vehicle during the charging process are acquired. Based on the charging parameters, the mutual inductance value between the vehicle's vehicle-side coil and the ground coil of the wireless charging pile is determined. The vehicle position is then detected in real time based on the mutual inductance value to obtain the vehicle position detection result. It is easy to note that by acquiring the first input current, the second input current, and the resonant network impedance, the mutual inductance can be actively corrected, thereby improving the accuracy and consistency of the mutual inductance estimation. This achieves the goal of accurately detecting the mutual inductance during vehicle alignment, thus improving the technical effect of improving the detection accuracy of mutual inductance during vehicle alignment, and solving the technical problem of low detection accuracy of mutual inductance during vehicle alignment in related technologies.

[0040] Optionally, determining the mutual inductance value between the vehicle-side coil and the wireless charging pile ground coil based on charging parameters includes: compensating the resonant network impedance based on a first preset relationship to obtain a target impedance, wherein the first preset relationship is used to characterize the mutual inductance difference between the resonant network impedance and the target impedance at different charging frequencies; determining the vehicle-side resonant parameters at different charging frequencies based on the target impedance and a first preset coefficient; compensating the first input current based on a second preset relationship to obtain a first target current, wherein the second preset relationship is used to characterize the current difference between the first input current and the actual input current at different mutual inductance values; and determining the mutual inductance value based on the first target current, the second input current, and the resonant parameters.

[0041] The first preset relationship mentioned above can be set by the user in advance, reflecting the preset relationship of the mutual inductance difference between the resonant network impedance and the target impedance at the same charging frequency. The mutual inductance difference between the resonant network impedance and the target impedance differs at different charging frequencies. The first target current mentioned above can be the actual input current of the vehicle-end coil during charging. The second preset relationship mentioned above can be set by the user in advance, reflecting the preset relationship of the current difference between the first input current and the actual input current at the same mutual inductance value. The current difference between the first input current and the actual input current differs at different mutual inductance values. The first preset coefficient mentioned above can be a constant value set by the user in advance to determine the resonant parameters. The specific value is not limited in this implementation; the user can set it according to actual needs.

[0042] In one optional embodiment, after obtaining the resonant network impedance, the resonant network impedance can first be compensated based on a first preset relationship to obtain the target impedance. Secondly, the target impedance and a first preset coefficient ω can be used to... s Determine the vehicle's resonance parameters. For example, this can be achieved by obtaining the product of the first and second target impedances, the square of the third target impedance, and the first preset coefficient ω. s The product of the first and second target impedances can be used to obtain the difference between the product and the square of the third target impedance and the first target impedance. Finally, the difference can be used to obtain the first preset coefficient ω. s The quotient of the product of the first and third target impedances can be used to obtain the vehicle's resonance parameters.

[0043] In another alternative embodiment, after obtaining the first input current, the first input current can first be compensated based on a second preset relationship to obtain the first target current I. ga Secondly, the mutual inductance value can be determined based on the first target current, the second input current, and the resonant parameters. For example, the quotient of the second input current and the first target current can be obtained, then the absolute value of the quotient can be taken, then the absolute value of the resonant parameters can be obtained, and finally the product of the two absolute values ​​can be obtained to determine the mutual inductance value.

[0044] Optionally, the target impedance includes: a first target impedance, a second target impedance, and a third target impedance, wherein the first target impedance is the impedance of the vehicle's first inductor, first capacitor, and second capacitor; the second target impedance is the impedance of the vehicle's second inductor and second capacitor; and the third target impedance is the impedance of the second capacitor. Based on the target impedance and a first preset coefficient, the vehicle's resonance parameters are determined, including: obtaining the product of the first target impedance and the second target impedance to obtain a first product; obtaining the square of the third target impedance to obtain a first squared value; obtaining the difference between the first product and the first squared value to obtain a first difference; obtaining the product of the third target impedance and the first preset coefficient to obtain a second product; obtaining the quotient of the first difference and the second product to obtain a first quotient; and obtaining the absolute value of the first quotient to obtain the resonance parameters.

[0045] Figure 2 This is a circuit diagram of an optional wireless charging system according to an embodiment of the present invention, such as... Figure 2 As shown, the system includes a ground assembly (GA) and a vehicle assembly (VA), wherein the vehicle assembly includes: a first inductor L va Second inductor L f_va First capacitor C va Second capacitor C f_va First resistor R va Diodes D1, D2, D3, and D4; transistors Q1 and Q2; and battery V. batt The ground terminal includes: the third capacitor C. f_ga Fourth capacitor C ga Third inductor L ga Fourth inductor L f_ga Second resistor R ga Diodes D5, D6, D7, D8, Q3, Q4, Q5, Q6, and the DC bus V bus A mutual inductance value M will be generated between the ground end and the vehicle end. (This is due to...) Figure 2 It can be seen that I ga I is the first target current input to the ground terminal coil. rec This is the second input current input to the vehicle-end coil.

[0046] It should be noted that the ground end mentioned above refers to the wireless charging station, and the vehicle end refers to the vehicle.

[0047] In an alternative embodiment, the first target impedance X1 can be obtained by the following formula:

[0048]

[0049] In another alternative embodiment, the second target impedance X2 can be obtained by the following formula:

[0050]

[0051] In another alternative implementation, the third target impedance X can be obtained using the following formula. va :

[0052]

[0053] In another alternative embodiment, the resonance parameter K can be obtained by the following formula:

[0054]

[0055] Optionally, the mutual inductance value is determined based on the first target current, the second input current, and the resonance parameter, including: obtaining the absolute value of the first target current to obtain a first absolute value, and obtaining the absolute value of the second input current to obtain a second absolute value; obtaining the quotient of the second absolute value and the first absolute value to obtain a second quotient; and obtaining the product of the second quotient and the resonance parameter to obtain the mutual inductance value.

[0056] In an alternative embodiment, the mutual inductance value M can be obtained using the following formula:

[0057]

[0058] Optionally, obtaining the first input current includes: obtaining the DC bus voltage of the wireless charging pile and the fourth target impedance of the third capacitor; and obtaining the first input current based on the DC bus voltage, the fourth target impedance, and the second preset coefficient.

[0059] The aforementioned second preset coefficient can be a constant value set by the user in advance to determine the first input current. The specific value is not limited in this embodiment, and the user can set it according to actual needs. In this embodiment, 0.9 is used as an example, but it is not limited to this.

[0060] In an alternative embodiment, the fourth target impedance can be obtained using the following formula:

[0061]

[0062] In another optional embodiment, after obtaining the DC bus voltage and the fourth target impedance, the first input current can be obtained based on the DC bus voltage, the fourth target impedance, and the second preset coefficient. For example, the product of the DC bus voltage and the second preset coefficient can be obtained, followed by the absolute value of the product and the absolute value of the fourth target impedance. Finally, the quotient of the absolute value of the product and the absolute value of the fourth target impedance can be obtained, which gives the first input current.

[0063] Optionally, the first input current is obtained based on the DC bus voltage, the fourth target impedance, and the second preset coefficient, including: obtaining the product of the second preset coefficient and the DC bus voltage to obtain a third product; obtaining the absolute value of the third product to obtain a third absolute value, and obtaining the absolute value of the fourth target impedance to obtain a fourth absolute value; obtaining the quotient of the third absolute value and the fourth absolute value to obtain the first input current.

[0064] In an alternative embodiment, the first input current I can be obtained by the following formula. ga ′:

[0065]

[0066] Optionally, the vehicle is detected based on the mutual inductance value to obtain the vehicle detection result, including: judging the mutual inductance value based on a preset threshold to obtain a judgment result, wherein the judgment result is used to characterize whether the mutual inductance value is less than or equal to the preset threshold; in response to the judgment result that the mutual inductance value is less than or equal to the preset threshold, determining that the detection result is that the vehicle is outside the preset charging area of ​​the wireless charging pile; in response to the judgment result that the mutual inductance value is greater than the preset threshold, determining that the detection result is that the vehicle is within the preset charging area of ​​the wireless charging pile.

[0067] In one optional embodiment, when the judgment result is that the mutual inductance value is less than or equal to a preset threshold, it can be determined that the detection result is that the vehicle is outside the preset charging area of ​​the wireless charging pile, that is, the vehicle and the wireless charging pile are not accurately aligned; when the comparison result is that the mutual inductance value is greater than the preset threshold, it indicates that the vehicle is within the preset charging area of ​​the wireless charging pile, that is, the vehicle and the wireless charging pile are accurately aligned.

[0068] This invention proposes a method for estimating mutual inductance under frequency conversion, and also provides a scheme for compensating mutual inductance after device parameter shifts.

[0069] The formula for calculating mutual inductance is as follows:

[0070]

[0071] When calculating mutual inductance using the above formula, only the parameters of the resonant network at the VA end need to be known, and the resonant parameters at the GA end do not need to be known.

[0072] According to the above formula, I ga This will affect the accuracy of mutual inductance calculations. To obtain an accurate current value, a current transformer can be used to directly measure the current in the coil. However, if it is not possible to sample the current in the GA coil using hardware, I can be obtained indirectly through mathematical calculations. ga Actual value.

[0073] There are two mathematical calculation models. The first is based on existing state-space equations, which will not be elaborated in this embodiment. The second is a simplified model using the following formula:

[0074]

[0075] Based on existing parameters, when the system is at its rated frequency of 85.5kHz and the DC bus voltage at the GA terminal is 400V, I ga This corresponds to 32.5A. The state-space equations and the aforementioned I... ga The calculation results for different frequencies corresponding to the calculation formula are as follows: Figure 3 As shown. Figure 3 This is an optional mutual inductance value according to an embodiment of the present invention, which varies with I. ga A schematic diagram of the changing calibration, as shown below. Figure 3 As shown, the horizontal axis represents the mutual inductance value M, and the vertical axis represents I. ga The values ​​on the horizontal axis are expressed in scientific notation. The actual value on the horizontal axis is the number on the axis multiplied by 10 to the power of 4. The horizontal line represents the target current value, i.e., I at the rated frequency of 85.5kHz. ga The coil current value, extending within the effective frequency band, shows an upward curve representing the accurate I corresponding to different mutual inductance values ​​calculated based on the state-space equation. ga The descending curve represents the I corresponding to different mutual inductance values ​​calculated using the calculation formula according to an embodiment of the present invention. ga As can be seen, when the frequency changes, the I corresponding to the same voltage... ga Significant changes will occur. Therefore, when the GA operates at different frequencies, it can be determined based on... Figure 3 The result is to actively conduct I ga Compensation ensures that the calculated results are consistent with the actual results.

[0076] Because of I rec This is the current at the input side of the rectifier on the vehicle side. The sampling circuit is easy to implement and can be directly integrated into the power control board on the vehicle side. Therefore, I rec It is considered reliable. Based on the mutual inductance calculation formula above, it can be seen that only K in the formula needs to be calculated and compensated for to ensure accuracy. The result is as follows... Figure 4 As shown, Figure 4This is a schematic diagram of an optional mutual inductance compensation calibration according to an embodiment of the present invention, such as... Figure 4 As shown, the horizontal axis represents frequency, and the vertical axis represents mutual inductance M. All values ​​on both axes are expressed in scientific notation. The unit for the horizontal axis is 10 kHz, and the unit for the vertical axis is... μ H, the thin solid line curve is the accurate M obtained from the state-space equation, and the dashed line curve is the I under different frequencies. ga The current is controlled to 32A, and the calculated M is shown by the thick solid line curve, which represents M obtained by ignoring the influence of frequency variation on the resonant network at the VA terminal, i.e., by using the mutual inductance calculation formula in the prior art. It can be seen that ignoring frequency variation will cause a significant deviation in the mutual inductance result. Therefore, corresponding compensation can be made according to the mutual inductance calculation formula of this invention.

[0077] Figure 5 This is a schematic diagram of an optional compensation design according to an embodiment of the present invention, such as... Figure 5 As shown, I was calculated. ga Then, the GA-end compensation algorithm can be used to adjust I. ga Compensation is performed to obtain the actual I. ga Then, the actual I can be compensated using the VA-end compensation algorithm. ga I rec By calculating the sampled values, operating frequency, and resonance parameters at the VA terminal, the mutual inductance value, or M value, can be obtained.

[0078] Figure 6 This is a flowchart of an optional mutual inductance calculation method according to an embodiment of the present invention, such as... Figure 6 As shown, the method includes the following steps:

[0079] Step S61: The vehicle begins to align with the ground charging station;

[0080] Step S62: After frequency division, start GA with random frequency, then proceed to steps S63 and S65.

[0081] Step S63, generate I of the target current frequency. ga ;

[0082] Step S64, compensate for the I at the corresponding frequency ga Proceed to step S66;

[0083] Step S65; VA waits, proceed to step S66;

[0084] Step S66, calculate and obtain I ga The actual value;

[0085] Step S67, based on the measured I rec I gaCalculate mutual inductance value from actual value;

[0086] Step S68: Determine alignment based on mutual inductance value.

[0087] Figure 7 This is a schematic diagram of an optional multi-vehicle-to-multi-pile wireless charging public application scenario according to an embodiment of the present invention, such as... Figure 7 As shown, the system includes multiple ground charging piles and multiple vehicles. Through the vehicle detection method of the present invention, the goal of accurately aligning any vehicle with any ground charging pile can be achieved.

[0088] According to the recommended method of the present invention, a practical wireless charging system for electric vehicles is calculated. The basic configuration of the system is: G coil self-inductance 40uH, VA coil self-inductance 50uH, and ground-end compensation network parameters L. f_ga =20.6uH, C f_ga =168.2nF, C ga =163nF, the on-board compensation network parameter is L f_va =15.4uH, C f_va =226nF, C va =100nF. The mutual inductance calculation result can be obtained using the formula proposed in this invention.

[0089] Table 1 is a comparison table of calculated and measured mutual inductance according to an embodiment of the present invention. As can be seen from Table 1, the calculated mutual inductance after compensation is consistent with the measured value. Therefore, it can be considered that the active compensation has achieved the expected effect.

[0090] Table 1 Comparison of Mutual Inductance Calculation and Actual Measurement

[0091]

[0092] Example 2

[0093] According to another aspect of the present invention, a vehicle position detection device is also provided. This device can perform the vehicle position detection method provided in Embodiment 1 above. The specific implementation method and preferred application scenario are the same as those in Embodiment 1 above, and will not be repeated here.

[0094] Figure 8 This is a schematic diagram of a vehicle position detection device according to an embodiment of the present invention, such as... Figure 8As shown, the device includes: an acquisition module 82, used to control the ground coil of the wireless charging pile to charge the vehicle and acquire the charging parameters of the vehicle during the charging process, wherein the charging parameters include: a first input current input to the ground coil, a second input current input to the vehicle-side rectifier bridge, and the resonant network impedance designed for the vehicle-side equipment; a determination module 84, used to determine the mutual inductance value between the vehicle-side coil and the ground coil of the wireless charging pile based on the charging parameters; and a detection module 86, used to detect the vehicle position in real time based on the mutual inductance value and obtain the detection result of the vehicle position, wherein the detection result is used to characterize whether the vehicle is located within the preset charging area of ​​the ground charging pile.

[0095] Optionally, the determining module includes: a first compensation unit, used to compensate the resonant network impedance based on a first preset relationship to obtain a target impedance, wherein the first preset relationship is used to characterize the mutual inductance difference between the resonant network impedance and the target impedance at different charging frequencies; a first determining unit, used to determine the resonant parameters of the vehicle end at different charging frequencies based on the target impedance and a first preset coefficient; a second compensation unit, used to compensate the first input current based on a second preset relationship to obtain a first target current, wherein the second preset relationship is used to characterize the current difference between the first input current and the actual input current at different mutual inductance values; and a second determining unit, used to determine the mutual inductance value based on the first target current, the second input current, and the resonant parameters.

[0096] Optionally, the target impedance includes: a first target impedance, a second target impedance, and a third target impedance, wherein the first target impedance is the impedance of the vehicle's first inductor, first capacitor, and second capacitor; the second target impedance is the impedance of the vehicle's second inductor and second capacitor; and the third target impedance is the impedance of the second capacitor. The first determining unit includes: a first obtaining subunit for obtaining the product of the first target impedance and the second target impedance to obtain a first product; a second obtaining subunit for obtaining the square of the third target impedance to obtain a first squared value; a third obtaining subunit for obtaining the difference between the first product and the first squared value to obtain a first difference; a fourth obtaining subunit for obtaining the product of the third target impedance and a first preset coefficient to obtain a second product; a fifth obtaining subunit for obtaining the quotient of the first difference and the second product to obtain a first quotient; and a sixth obtaining subunit for obtaining the absolute value of the first quotient to obtain the resonance parameter.

[0097] Optionally, the second determining unit includes: a seventh obtaining subunit, used to obtain the absolute value of the first target current to obtain the first absolute value, and to obtain the absolute value of the second input current to obtain the second absolute value; an eighth obtaining subunit, used to obtain the quotient of the second absolute value and the first absolute value to obtain the second quotient; and a ninth obtaining subunit, used to obtain the product of the second quotient and the resonance parameter to obtain the mutual inductance value.

[0098] Optionally, the acquisition module includes: a first acquisition unit for acquiring the DC bus voltage of the wireless charging pile and the fourth target impedance of the third capacitor; and a processing unit for obtaining a first input current based on the DC bus voltage, the fourth target impedance, and a second preset coefficient.

[0099] Optionally, the processing unit includes: a tenth acquisition subunit, used to acquire the product of the second preset coefficient and the DC bus voltage to obtain a third product; an eleventh acquisition subunit, used to acquire the absolute value of the third product to obtain a third absolute value, and acquire the absolute value of the fourth target impedance to obtain a fourth absolute value; and a twelfth acquisition subunit, used to acquire the quotient of the third absolute value and the fourth absolute value to obtain a first input current.

[0100] Optionally, the detection module includes: a judgment unit, used to judge the mutual inductance value based on a preset threshold and obtain a judgment result, wherein the judgment result is used to characterize whether the mutual inductance value is less than or equal to the preset threshold; a third determination unit, used to determine the detection result as the vehicle is located outside the preset charging area of ​​the wireless charging pile in response to the judgment result that the mutual inductance value is less than or equal to the preset threshold; and a fourth determination unit, used to determine the detection result as the vehicle is located within the preset charging area of ​​the wireless charging pile in response to the judgment result that the mutual inductance value is greater than the preset threshold.

[0101] Example 3

[0102] According to another aspect of the present invention, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored program, wherein, when the program is running, the device on which the computer-readable storage medium is located executes any of the above methods.

[0103] Example 4

[0104] According to another aspect of the present invention, a vehicle is also provided, including a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform any of the methods described above.

[0105] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0106] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0107] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0108] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0109] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0110] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0111] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A vehicle position detection method, characterized in that, include: The wireless charging pile ground coil is controlled to charge the vehicle, and the charging parameters of the vehicle during the charging process are obtained. The charging parameters include: a first input current input to the ground coil, a second input current input to the vehicle-side rectifier bridge, and the resonant network impedance designed for the vehicle-side equipment. Based on the charging parameters, the mutual inductance value between the vehicle-side coil and the ground-side coil of the wireless charging pile is determined. The vehicle's location is detected in real time based on the mutual inductance value to obtain the detection result of the vehicle's location, wherein the detection result is used to characterize whether the vehicle is located within the preset charging area of ​​the wireless charging pile. Based on the charging parameters, determining the mutual inductance value between the vehicle-side coil and the ground-side coil of the wireless charging pile includes: compensating the resonant network impedance based on a first preset relationship to obtain a target impedance, wherein the first preset relationship is used to characterize the mutual inductance difference between the resonant network impedance and the target impedance at different charging frequencies; determining the vehicle-side resonant parameters at different charging frequencies based on the target impedance and a first preset coefficient; compensating the first input current based on a second preset relationship to obtain a first target current, wherein the second preset relationship is used to characterize the current difference between the first input current and the actual input current at different mutual inductance values; and determining the mutual inductance value based on the first target current, the second input current, and the resonant parameters. The target impedance includes: a first target impedance, a second target impedance, and a third target impedance. The first target impedance is the impedance of the vehicle's first inductor, first capacitor, and second capacitor; the second target impedance is the impedance of the vehicle's second inductor and second capacitor; and the third target impedance is the impedance of the second capacitor. Determining the vehicle's resonance parameters based on the target impedance and a first preset coefficient includes: obtaining the product of the first target impedance and the second target impedance to obtain a first product; obtaining the square of the third target impedance to obtain a first squared value; obtaining the difference between the first product and the first squared value to obtain a first difference; obtaining the product of the third target impedance and the first preset coefficient to obtain a second product; obtaining the quotient of the first difference and the second product to obtain a first quotient; and obtaining the absolute value of the first quotient to obtain the resonance parameters.

2. The method according to claim 1, characterized in that, Determining the mutual inductance value based on the first target current, the second input current, and the resonance parameters includes: Obtain the absolute value of the first target current to obtain the first absolute value, and obtain the absolute value of the second input current to obtain the second absolute value; The quotient of the second absolute value and the first absolute value is obtained to obtain the second quotient. The mutual inductance value is obtained by multiplying the second quotient value by the resonance parameter.

3. The method according to claim 1, characterized in that, Obtaining the first input current includes: Obtain the DC bus voltage of the wireless charging pile and the fourth target impedance of the third capacitor; The first input current is obtained based on the DC bus voltage, the fourth target impedance, and the second preset coefficient.

4. The method according to claim 3, characterized in that, Based on the DC bus voltage, the fourth target impedance, and the second preset coefficient, the first input current is obtained, including: The third product is obtained by multiplying the second preset coefficient by the DC bus voltage; Obtain the absolute value of the third product to obtain the third absolute value, and obtain the absolute value of the fourth target impedance to obtain the fourth absolute value; The first input current is obtained by obtaining the quotient of the third absolute value and the fourth absolute value.

5. The method according to claim 1, characterized in that, The vehicle position is detected in real time based on the mutual inductance value to obtain the detection result of the vehicle position, including: The mutual inductance value is judged based on a preset threshold to obtain a judgment result, wherein the judgment result is used to characterize whether the mutual inductance value is less than or equal to the preset threshold; In response to the judgment result that the mutual inductance value is less than or equal to the preset threshold, the detection result is determined to be that the vehicle is located outside the preset charging area of ​​the wireless charging pile; In response to the judgment result that the mutual inductance value is greater than the preset threshold, the detection result is determined to be that the vehicle is located within the preset charging area of ​​the wireless charging pile.

6. A vehicle position detection device, characterized in that, include: The acquisition module is used to control the ground coil of the wireless charging pile to charge the vehicle and acquire the charging parameters of the vehicle during the charging process. The charging parameters include: a first input current input to the ground coil, a second input current input to the vehicle-side rectifier bridge, and the resonant network impedance designed for the vehicle-side equipment. The determining module is used to determine the mutual inductance value between the vehicle-side coil and the ground-side coil of the wireless charging pile based on the charging parameters. The detection module is used to detect the vehicle's position in real time based on the mutual inductance value, and obtain the detection result of the vehicle's position, wherein the detection result is used to characterize whether the vehicle is located within the preset charging area of ​​the wireless charging pile; The determining module is further configured to compensate the resonant network impedance based on a first preset relationship to obtain a target impedance, wherein the first preset relationship is used to characterize the mutual inductance difference between the resonant network impedance and the target impedance at different charging frequencies; determine the resonant parameters of the vehicle end at different charging frequencies based on the target impedance and a first preset coefficient; compensate the first input current based on a second preset relationship to obtain a first target current, wherein the second preset relationship is used to characterize the current difference between the first input current and the actual input current at different mutual inductance values; and determine the mutual inductance value based on the first target current, the second input current, and the resonant parameters. The target impedance includes: a first target impedance, a second target impedance, and a third target impedance, wherein the first target impedance is the impedance of the first inductor, the first capacitor, and the second capacitor of the vehicle; the second target impedance is the impedance of the second inductor and the second capacitor of the vehicle; and the third target impedance is the impedance of the second capacitor. The determining module is further configured to obtain the product of the first target impedance and the second target impedance to obtain a first product; obtain the square of the third target impedance to obtain a first squared value; obtain the difference between the first product and the first squared value to obtain a first difference; obtain the product of the third target impedance and the first preset coefficient to obtain a second product; obtain the quotient of the first difference and the second product to obtain a first quotient; and obtain the absolute value of the first quotient to obtain the resonance parameter.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device on which the computer-readable storage medium is located to perform the method according to any one of claims 1 to 5.

8. A vehicle comprising a memory and a processor, characterized in that, The memory stores a computer program, and the processor is configured to run the computer program to perform the method according to any one of claims 1 to 5.

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