Wireless charging vehicle guiding and positioning method

Abstract

The invention discloses a wireless charging vehicle guiding and positioning method, which comprises the following steps of: establishing communication between a ground end and a vehicle end, then exchanging charging information and carrying out compatibility check, and after the compatibility check is passed, establishing a first coordinate system by taking a vehicle end communication device as a first original point P1; taking a fixed point on the parking space as a second original point P2, establishing a second coordinate system, and mapping the second coordinate system to the first coordinate system to form a corresponding coordinate mapping relation; the vehicle-end communication device communicates with the ground-end communication device, and obtains an initial distance L0 between the vehicle-end communication device and the ground-end communication device; the vehicle moves to the charging position, the ground end communication device moves at least two times along with the transmitting end according to a preset distance, and the vehicle end communication device communicates with the ground end communication device every time the transmitting end moves, so that the distance between the vehicle end communication device and the ground end communication device is obtained; according to the first relation and the second relation, obtaining a specific value of a coordinate of the second origin P2 mapped to the first coordinate system; the method is high in precision and high in adaptability to the environment, and the efficiency and convenience of wireless charging are greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of wireless charging, and in particular to a method for guiding and positioning a wireless charging vehicle. Background Art

[0002] As an ideal power supply method for electric vehicles, high-power wireless charging has been rapidly developed and widely used in recent years due to its safety, convenience and high degree of automation. During wireless charging, the transmitting coil and the receiving coil need to be aligned as much as possible to obtain the maximum coupling coefficient and achieve the maximum energy transmission efficiency. Therefore, electric vehicles are generally equipped with an alignment detection system to provide coil alignment guidance for the driver or automatic driving system of the vehicle. The existing alignment technology generally uses the difference between the transmitting power and the receiving power to determine whether it is aligned. In some solutions, cameras are installed to assist in alignment.

[0003] These two methods have large errors, are greatly affected by the environment, the working environment of the camera is not easy to guarantee, and the cost is high. Further facing the latest technology - mobile transmitter, these two methods can no longer meet the needs. Summary of the invention

[0004] The present invention provides a wireless charging vehicle guidance and positioning method, which can efficiently and accurately guide the vehicle to perform wireless charging.

[0005] Before executing the wireless charging vehicle guidance and positioning method, the ground end and the vehicle end establish communication, then exchange charging information and perform a compatibility check. After the compatibility check is passed: start the wireless charging vehicle guidance and positioning method, take the initial position of the vehicle-end communication device as the first origin P1, establish a first coordinate system, the horizontal axis X1 is the current driving direction of the vehicle, the vertical axis Y1 is the initial direction of the axle, and the vertical axis Z1 is the direction perpendicular to the bottom surface of the vehicle; take a fixed point on the parking space as the second origin P2, establish a second coordinate system, the horizontal axis X2 is the length direction of the parking space, the vertical axis Y2 is the width direction of the parking space, and the vertical axis Z2 is the direction perpendicular to the parking space; the projection angle difference between the horizontal axis X1 of the first coordinate system and the horizontal axis X2 of the second coordinate system is θ; map the second coordinate system to the first coordinate system to form a corresponding coordinate mapping relationship; the vehicle-end communication device D communicates with the ground-end communication device E, and obtains the initial distance L between the two 0 During the movement of the vehicle to the charging position, the ground communication device E moves at least N times with the transmitter according to the predetermined distance. Each time the transmitter moves, the vehicle communication device D communicates with the ground communication device E to obtain the Nth distance L between the two. N ; N is equal to 2; According to the following relationship 1 and relationship 2, the specific value of the coordinate of the second origin P2 mapped to the first coordinate system is obtained; the first relationship is: the initial distance L 0 , the distance between the vehicle-side communication device D and the ground-side communication device E in the first coordinate system; the second relationship is: the Nth distance LN , the distance between the vehicle-end communication device D and the ground-end communication device E in the first coordinate system after each movement.

[0006] Preferably, the coordinates of the ground communication device E in the second coordinate system are (A M ,B M ,C M ); The coordinates of the second origin P2 mapped to the first coordinate system are (A P ,B P ,C P ), the coordinates of the ground communication device E mapped to the first coordinate system are:

[0007] [(A P +A M ·cosθ+B M ·sinθ),(B P +B M ·cosθ-A M ·sinθ),(C M +C P )];

[0008] Preferably, the first relationship is:

[0009] Formula 1: L 0 2 =[(A P +A M ·cosθ+B M ·sinθ)-0] 2 +[(B P +B M ·cosθ-A M ·sinθ)-0] 2 +[(C P +C M )-0] 2 ;

[0010] The second relationship is:

[0011] Formula 2: L N 2 ={[A P +(A m +A 2N )·cosθ+(B m +B 2N )·sinθ]-A 1N} 2 +{[B P +(B m +B 2N )·cosθ-(A m +A 2N )·sinθ]-B1N} 2 +[(C P +C M )-0] 2 ;

[0012] A 1N is the moving distance of the vehicle-side communication device D on the horizontal axis X1 in the first coordinate system after the transmitter moves N times; 1N A is the moving distance of the vehicle-side communication device D on the longitudinal axis Y1 in the first coordinate system after the transmitter moves N times; 2N is the moving distance of the ground communication device E on the horizontal axis X2 in the second coordinate system after the transmitting end moves N times; 2N It is the moving distance of the ground communication device E on the vertical axis Y2 in the second coordinate system after the transmitting end moves N times.

[0013] Preferably, each time the Nth distance L is obtained N At the same time, the coordinates of the vehicle-side communication device D in the first coordinate system are obtained, and the coordinates of the ground communication device in the second coordinate system are also obtained, and the coordinates of the ground communication device in the first coordinate system are obtained according to the coordinate mapping relationship.

[0014] Preferably, the coordinates of the vehicle-side communication device D in the first coordinate system are (A 1N ,B 1N ,0); at the same time, the coordinates of the ground communication device in the second coordinate system are (A m +A 2N ,B m +B 2N , C M ).

[0015] Preferably, when N=2, Formula 2 is divided into:

[0016] Formula 2.1: L 1 2 ={[A P +(A m +A 21 )·cosθ+(B m +B 21 )·sinθ]-A 11} 2 +{[B P +(B m +B 21 )·cosθ-(A m +A 21 )·sinθ]-B 11} 2 +[(C P +C M )-0] 2 ;

[0017] Formula 2.2: L 2 2 ={[A P +(A m +A 22 )·cosθ+(B m +B 22 )·sinθ]-A 12} 2 +{[B P +(B m +B 22 )·cosθ-(A m +A 22 )·sinθ]-B 12} 2 +[(C P +C M )-0] 2 .

[0018] The method of the present invention can obtain the coordinate data of the vehicle-side communication device and the ground-side communication device through the mapping of two coordinate systems, and can also obtain the corresponding actual measurement data, thereby calculating the positional relationship between the two in the same coordinate system, thereby guiding the positioning. The method has high accuracy, strong adaptability to the environment, and greatly improves the efficiency and convenience of wireless charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the vehicle end and the ground end;

[0020] Figure 2 It is a schematic diagram of two coordinate systems;

[0021] Figure 3 It is a schematic diagram of mapping the second coordinate system to the first coordinate system.

[0022] Figure 4-Figure 6 The distance relationship between the vehicle-side communication device and the ground-side communication device at different positions is illustrated respectively. DETAILED DESCRIPTION

[0023] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention.

[0024] The present invention discloses a wireless charging vehicle guidance and positioning method, which has the advantages of high guidance accuracy and high efficiency. Especially for the wireless charging technology with a movable transmitting end, it also reduces the technical requirements for the driver to park the vehicle, greatly increasing the convenience of wireless charging.

[0025] For easier understanding, let's first explain the wireless charging system.

[0026] The wireless charging system is divided into a transmitting end (also called a ground end or ground end) and a receiving end (also called a vehicle-mounted end or vehicle end). The specific working principle is known to those skilled in the art and will not be described in detail in this application. Compared with traditional electric vehicle wireless charging, this solution is more suitable for situations where the transmitting end can be moved, such as the Chinese patents CN116054433B and CN116252645A, where the transmitting end moves so that the transmitting coil can move.

[0027] The vehicle end has a power receiving coil (receiving coil for short), a vehicle end communication device D, etc., and the ground end has a power transmitting coil (transmitting coil for short), a ground end communication device E, etc. In this solution, the ground end communication device E moves with the transmitting end.

[0028] Compared with the solution with a fixed transmitter, the mobile solution has lower requirements for vehicle parking, because the transmitter can move to the alignment position by itself, thereby greatly improving the convenience of wireless charging.

[0029] The wireless charging vehicle guidance and positioning method (hereinafter referred to as the method) is a part of the entire wireless charging process. For ease of understanding, the following description will start with the establishment of a communication connection between the vehicle and the ground before charging.

[0030] The overall process can be divided into: ① Establish communication between the ground terminal and the vehicle terminal → ② Exchange charging information and perform compatibility check → ③ Guide positioning → ④ The vehicle is parked within a certain range directly above the ground terminal (i.e. enters the parking space) → ⑤ Complete further compatibility check → ⑥ Start charging. This application mainly focuses on the specific method of ③.

[0031] Specifically, the two parties exchange charging information and perform compatibility checks to confirm that they match each other. The vehicle end and the ground end will clarify what the verification of the information to be sent is in this communication. When multiple vehicles are parked in multiple adjacent parking spaces at the same time, the ground end can determine which signal is the matching vehicle to be charged when receiving multiple signals. For example, the vehicle end can tell the ground end that the first 8 bits of the information sent by the vehicle are the unique verification code "********".

[0032] At the same time, the ground end will clarify the relative positions of its communication end, parking space line, and movable range of the transmitting coil on the ground in this communication. Based on these relative positions, the layout status of the entire parking space ground equipment can be depicted, and it will be used to guide the alignment of the vehicle end and the center point of the ground end transmitting coil, which can also increase interoperability.

[0033] After both parties complete the above matching, they start further ranging and positioning, thereby achieving guided positioning. Figure 1 , the left side is the vehicle to be charged, and the right side is the charging parking space. In this method, the dashed line in the figure indicates that the vehicle-side communication device D communicates with the ground-side communication device E, and the dotted line indicates that the ground-side communication device E can move with the transmitter.

[0034] The specific method of guiding positioning is described below.

[0035] First, establish two coordinate systems, such as Figure 1 As shown, a first coordinate system with the initial position of the vehicle-side communication device D as the first origin P1, and a second coordinate system with a fixed point on the parking space as the second origin P2 (the first and second here are used for distinction, not to limit the order of selecting the respective origins). Figure 1 The upper left corner of the parking space is selected as the second origin P2.

[0036] The horizontal axis X1 of the first coordinate system is the current driving direction of the vehicle, the vertical axis Y1 is the initial direction of the axle, and the vertical axis Z1 is the direction perpendicular to the bottom surface of the vehicle. In the second coordinate system, the horizontal axis X2 is the length direction of the parking space, the vertical axis Y2 is the width direction of the parking space, and the vertical axis Z2 is the direction perpendicular to the parking space.

[0037] It can be seen that the coordinates of the first origin P1 in the first coordinate system are (0,0,0), but it should be noted that the distance between the first origin P1 and the ground is not zero, but a fixed value, which is determined by the installation position of the vehicle-side communication device D. In the second coordinate system, the position of the ground-side communication device E relative to the second origin P2 is known, and its initial coordinates are (A M ,B M ,C M ), the parking space floor is generally considered horizontal, C M is 0.

[0038] The difference in projection angle between the first coordinate system horizontal axis X1 and the second coordinate system horizontal axis X2 of the above two coordinate systems is θ. That is, when the orthographic projection is made along the direction of the vertical axis Z1 or the vertical axis Z2, the difference in angle between the projections of the first coordinate system horizontal axis X1 and the second coordinate system horizontal axis X2 on the same plane is θ. Figure 2, is explained by taking the difference of the counterclockwise rotation angle of X2 to X1 as θ. If it involves clockwise rotation, it can be converted to counterclockwise rotation angle. For example, if the clockwise rotation is 10°, it can be calculated as 350° counterclockwise rotation.

[0039] See also Figure 2 , the vertical axis Z1 and the vertical axis Z2 are overlapped to better show the angle difference. On this basis, the second coordinate system can be mapped to the first coordinate system to form a corresponding coordinate mapping relationship. In other words, the coordinates of each point on the ground can be shown in the first coordinate system, similar to Figure 3 As shown, the second coordinate system is mapped to the first coordinate system, so that, for example, the ground communication device E can obtain the coordinates in the first coordinate system.

[0040] The coordinates of the second origin P2 mapped to the first coordinate system are (A P ,B P ,C P ); Mapping the ground communication device E to the first coordinate system, its coordinates in the first coordinate system can be obtained as:

[0041] [(A P +A M ·cosθ+B M ·sinθ),(B P +B M ·cosθ-A M ·sinθ),(C M +C P )].

[0042] Theoretically, the above coordinates can be used to obtain the relative position of the vehicle to be charged, the available wireless charging parking space, and the ground end of the wireless charging device, and then guide the vehicle to park and align. Therefore, in the above formula, as long as A is obtained P , B P , C P The values ​​of and θ can determine the position. The following will explain how to obtain these values ​​step by step. P is the easiest to obtain, because the first origin P1 is the vehicle-side communication device D, and its distance from the ground is fixed, so C P The value is the same as the fixed value mentioned above, but it is a negative number because the first origin is on the vehicle and the ground is below the vehicle. In summary, the minimum value is A P , B P , θ can be any of these three values. It should be noted that A M ,B M ,C M is the value in the second coordinate system and is therefore known.

[0043] The above-mentioned coordinate data are obtained by establishing coordinates. By combining these data with actual measurement data, the above-mentioned values ​​can be obtained. The data of the actual measurement data may include the following contents and methods.

[0044] like Figure 4 As shown, the vehicle-side communication device D communicates with the ground-side communication device E to obtain the initial distance L between the two. 0 For example, the RSSI method (Received Signal Strength Indication) can be used, and the ground communication device E calculates the initial distance L based on the received signal strength or time difference. 0 , and transmits this distance to the vehicle controller. Alternatively, the vehicle end can directly calculate the distance based on the signal sent by the ground end. 0 The specific method of obtaining is only an example, and it is not limited to using only this method.

[0045] At this time, the initial distance is the actual measurement data, and the distance between the vehicle-side communication device D and the ground-side communication device E in the first coordinate system is the coordinate data. At this time, the measurement data and the coordinate data are in a first relationship, and the first relationship can be expressed by the following formula 1.

[0046] Formula 1: L 0 2 =[(A P +A M ·cosθ+B M ·sinθ)-0] 2 +[(B P +B M ·cosθ-A M ·sinθ)-0] 2 +[(C M +C P )-0] 2 .

[0047] As mentioned above, at least get an A P , B P Obviously, one formula 1 is not enough to obtain three values. Therefore, in the case where the transmitter can move, the second relationship can be obtained by moving the charging vehicle and the transmitter. And, with different movement times, there can be multiple formulas in the second relationship.

[0048] Specifically: the vehicle moves to the charging position, and the ground communication device E moves at least N times with the transmitter according to the predetermined distance. Each time the transmitter moves, the vehicle communication device D communicates with the ground communication device E to obtain the Nth distance L between the two. N ; N is greater than or equal to 2. Figure 5 and Figure 6 , showing the corresponding positional relationship.

[0049] The second relationship is: the Nth distance L N , the distance between the vehicle-end communication device D and the ground-end communication device E in the first coordinate system after each movement.

[0050] Regardless of the value of N, relation 2 can be expressed by the following formula 2.

[0051] Formula 2: L N 2 ={[A P +(A m +A 2N )·cosθ+(B m +B 2N )·sinθ]-A 1N} 2 +{[B P +(B m +B 2N )·cosθ-(A m +A 2N )·sinθ]-B 1N} 2 +[(C P +C M )-0] 2 ; A 1N is the moving distance of the vehicle-side communication device D on the horizontal axis X1 in the first coordinate system after the transmitter moves N times; 1N A is the moving distance of the vehicle-side communication device D on the longitudinal axis Y1 in the first coordinate system after the transmitter moves N times; 2N is the moving distance of the ground communication device E on the horizontal axis X2 in the second coordinate system after the transmitting end moves N times; 2N It is the moving distance of the ground communication device E on the vertical axis Y2 in the second coordinate system after the transmitting end moves N times.

[0052] It should be noted that when the vehicle is moving, the transmitter drives the ground communication device E to move as well. The N times here does not necessarily mean that the transmitter must "move once, stop, and move again". It can complete "the vehicle communication device D communicates with the ground communication device E to obtain the Nth distance L between the two" during the continuous movement. N ". That is, each communication can be completed and the corresponding distance can be obtained, and the specific movement method is not limited. The movement of the transmitting end does not affect the movement of the vehicle when it is parked.

[0053] Combination Figure 5 and Figure 6, taking N as 2 as an example, that is, during the movement of the vehicle, the transmitter moves twice, and each time it will re-obtain the distance between the vehicle-side communication device D and the ground-side communication device E - the first distance L 1 and the second distance L 2 , and these two distances are obtained in a similar way to the initial distance, so that actual measurement data can be obtained.

[0054] Further, according to the two coordinate systems, the first distance L 1 and the second distance L 2 The corresponding coordinate data can also be obtained, namely, the following formula 2.1 and formula 2.2.

[0055] Formula 2.1: L 1 2 ={[A P +(A m +A 21 )·cosθ+(B m +B 21 )·sinθ]-A 11} 2 +{[B P +(B m +B 21 )·cosθ-(A m +A 21 )·sinθ]-B 11} 2 +[(C P +C M )-0] 2 ;

[0056] Formula 2.2: L 2 2 ={[A P +(A m +A 22 )·cosθ+(B m +B 22 )·sinθ]-A 12} 2 +{[B P +(B m +B 22 )·cosθ-(A m +A 22 )·sinθ]-B 12} 2 +[(C P +C M )-0] 2 .

[0057] In summary, through the three equations of formula 1, formula 2.1 and formula 2.2, we can solve A P, B P , and θ are the three values.

[0058] For ease of understanding, the first movement of the transmitter is taken as an example for explanation.

[0059] The vehicle moves, that is, moves to the parking position. The ground communication device will also move in at least one direction. The movement is configured when it is initialized. The vehicle-side communication device D of the vehicle to be charged and the ground communication device E complete the distance measurement again at a certain time. The specific time is not limited, but it should be a reasonable time, for example, 0.5 seconds different from the initial distance measurement. Here, "again" means measuring the first distance again after measuring the initial distance.

[0060] At this time, the vehicle moves A on the horizontal axis X1 in the first coordinate system relative to the initial position. 11 , (This distance can be obtained by combining the vehicle's own related sensors and the vehicle's own structural characteristics with the vehicle dynamics model to obtain the vehicle's motion trajectory, and then obtain the components on each axis, which can be positive or negative. The above-mentioned related sensors can be, for example, wheel speed sensors, steering wheel angle sensors, vehicle acceleration sensors, etc.; examples of the vehicle's own structural characteristics include, for example, wheelbase, tire diameter, etc.), the longitudinal axis Y1 direction in the first coordinate system moves B 11 (This distance can be known through related sensors similar to the above and the structural characteristics of the vehicle itself, and can be positive or negative). The ground communication device M moves A on the horizontal axis X2 in the second coordinate system relative to the initial position. 21 (The movement of the ground communication device E is preset, so the distance is known and can be positive or negative), it moves B on the vertical axis Y2 in the second coordinate system 21 (The movement of the ground communication device E is preset, so the distance is known and can be positive or negative.) Since the ground communication device E moves in at least one direction, A 21 and B 21 At least one of them is not 0.

[0061] The following conclusions were drawn:

[0062] At this time, the vehicle-side communication device D moves (A) relative to the initial position (in the first coordinate system) 11 , B 11 , 0), at this time, the coordinate of the vehicle-side communication device D in the first coordinate system is updated to (A 11 , B 11 , 0). The coordinates of the ground communication device in the second coordinate system become (A m +A 21 , B m +B 21 , C M ).

[0063] After the ground communication device M is mapped to the first coordinate system, the coordinates are: [A P +(A m +A 2N )·cosθ+(B m +B 2N )·sinθ,B P +(B m +B 2N )·cosθ-(A m +A 2N )·sinθ,C P +C M ].

[0064] Through the above mapped coordinates, we can get formula 2.1. And by analogy, we can get formula 2.2.

[0065] As the vehicle continues to move, N can have more values, so formula 2 can derive more sub-formulas 2.N. The more data there is, the more concentrated coordinate values ​​can be used through certain data screening methods (such as mode), thus achieving higher guidance and positioning accuracy.

[0066] Through the movement of the vehicle and the ground communication device M, the distance will be continuously adjusted, increasing or decreasing (but according to the motion trajectory, the coordinate changes caused by the movement are knowable), and the multiple sets of data obtained are continuously iterated and cross-checked to obtain a more accurate relative position of the vehicle-side communication device D and the ground-side communication device.

[0067] By combining the relative position of the vehicle-side communication device D and the center of the receiving coil, and the relative position of the ground-side communication device E and the center of the ground-side transmitting coil, the vehicle can be guided to move and stop at the correct charging position.

[0068] In this method, the second coordinate system is mapped to the first coordinate system so that the relative positions of the ground end and the vehicle end can be known, thereby guiding the parking of the vehicle. Moreover, because the transmitting end is movable, the guiding positioning is also applicable to guiding the movement of the transmitting end. As mentioned above, the ground communication device E moves at least N times with the transmitting end at a predetermined distance. After the second movement, the positions of the transmitting end and the receiving end can be clearly determined by the above method. Therefore, the subsequent movement of the transmitting end can be based on the relative positions of the ground end and the vehicle end, and can move in the direction of the trend of aligning the transmitting coil and the receiving coil.

[0069] That is, the transmitting end moves at least N times according to the predetermined distance, the first and second times are moved according to the predetermined distance, and the third to Nth times are planned according to the specific value of the coordinates mapped from the second origin P2 to the first coordinate system, so as to ensure that the transmitting coil and the receiving coil are synchronously aligned when the vehicle is parked in place.

[0070] Supplementary explanation: In the process of calculating the initial distance, the UWB (ultra-wideband wireless communication technology) algorithm can also be applied. At this time, the RSSI method used to obtain the distance in the above algorithm will not be applicable, and it will be replaced by the two-way time of flight method (TW-TOF). Ultra-wideband wireless communication technology (UWB) is a carrier-free communication technology. UWB does not use a carrier, but uses a short energy pulse sequence and extends the pulse to a frequency range through orthogonal frequency division modulation or direct sequencing. The traditional communication method uses a continuous wave signal, that is, the local oscillator generates a continuous high-frequency carrier, and the information to be transmitted is loaded on the carrier through methods such as amplitude modulation and frequency modulation, and sent through the antenna. Current wireless broadcasting, 4G communication, WIFI, etc. all use this method for wireless communication; while IR-UWB signals do not need to generate a continuous high-frequency carrier, but only need to generate a pulse as short as nS level, which can be sent through the antenna. The information that needs to be transmitted can be loaded by changing the amplitude, time, and phase of the pulse, thereby realizing information transmission. UWB can achieve data transmission rates of hundreds of Mbit / s to 2Gbit / s by transmitting extremely low-power signals over a wide spectrum, and has many advantages such as strong penetration, low power consumption, good anti-interference effect, high security, large spatial capacity, and accurate positioning.

[0071] The three commonly used positioning algorithms for UWB positioning include TDOA positioning algorithm, TOF positioning algorithm, and TOA positioning algorithm. These three algorithms can directly adopt existing solutions, and this application will not elaborate on them.

[0072] When using the TOF positioning algorithm (Time of flight), in order to reduce the ranging error caused by the clock offset, the measurement method in both the forward and reverse directions can be used, that is, the remote base station sends the ranging information, the tag receives the ranging information and replies, and then the tag initiates the ranging information, and the remote base station replies. By taking the average value of the flight time, the time offset between the two is reduced, thereby improving the ranging accuracy. Here is just an improvement in one aspect of the TOF algorithm. The above default ground is flat. If there is an inclination angle on the ground in practice, the inclination angle can be injected into the ground communication device in advance and brought into the actual calculation. At this time, a new Z phase unknown may be introduced, and each calculation needs to introduce a set of formulas, that is, the value of N must be 3. Of course, the ground where wireless charging is generally installed is required to be flat, otherwise the ground end will be in an inclined state after moving, which is not conducive to wireless charging. Even if the ground is not flat, it will be manually leveled when the ground end is installed.

[0073] In the present invention, at least one ground-side communication device is required on the ground, which can move in at least one direction, and the larger the range of movement, the better. The vehicle needs at least one vehicle-side communication device D, which can be fixed or movable relative to the vehicle, such as moving with the tires. Regardless of whether it moves or not, the coordinates of its new point are updated. If it moves, new variables may be generated, increasing the amount of calculation, but if more checks are introduced, the calculation will be more accurate. For the sake of simplicity, the vehicle-mounted communication device is generally fixed on the vehicle.

[0074] After the ground end of the wireless charging device establishes communication with the vehicle end, the vehicle end and the ground end should confirm the verification content to ensure that multiple vehicles and multiple parking spaces communicate without interfering with each other. The ground end should also tell the vehicle end the position of its communication device relative to the center point of the ground end transmitting coil and the position relative to the parking space, and a distinction should be made, such as numbering.

[0075] The movement trajectory of the ground-end communication device should also be known, and the ground-end will inform the vehicle-end of the movement-related information during communication.

[0076] In addition, when the vehicle moves to the charging position, whether it is a straight line or a curve, it does not affect the implementation of the method. The interoperability between different brands and models of vehicles and different wireless charging devices is strong; the vehicle-side communication device D can be reused with certain existing components on the vehicle, such as the signal sensor of the door handle.

[0077] Because formula 2 can derive more sub-formulas according to the value of N, redundant variables can be added during the calculation process, and the calculation results can be compared and verified with each other to reduce the calculation error. Multiple sets of data are continuously iterated and calculated, and the positioning accuracy is high; when the parking space line is blurred or the vehicle cannot recognize the parking space line, this method is still feasible and can also prevent the vehicle from parking in the wrong place.

[0078] The above describes in detail the structure, features and effects of the present invention based on the embodiments shown in the drawings. The above is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown in the drawings. Any changes made according to the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the description and drawings, should be within the protection scope of the present invention.

Claims

1. A wireless charging vehicle guidance and positioning method, It is characterized in that Before executing the wireless charging vehicle guidance positioning method, the ground end and the vehicle end establish communication, then exchange charging information and perform compatibility check. After the compatibility check passes: Taking the initial position of the vehicle-side communication device as the first origin P1, a first coordinate system is established, wherein the horizontal axis X1 is the current driving direction of the vehicle, the vertical axis Y1 is the initial direction of the axle, and the vertical axis Z1 is the direction perpendicular to the bottom surface of the vehicle; A second coordinate system is established with a fixed point on the parking space as the second origin P2, wherein the horizontal axis X2 is the length direction of the parking space, the vertical axis Y2 is the width direction of the parking space, and the vertical axis Z2 is the direction perpendicular to the parking space; The difference in projection angle between the horizontal axis X1 of the first coordinate system and the horizontal axis X2 of the second coordinate system is θ; Mapping the second coordinate system to the first coordinate system to form a corresponding coordinate mapping relationship; The vehicle-side communication device (D) communicates with the ground-side communication device (E) and obtains the initial distance L between the two. 0 ; When the vehicle moves to the charging position, the ground communication device (E) moves at least N times with the transmitter according to the predetermined distance. Each time the transmitter moves, the vehicle communication device (D) communicates with the ground communication device (E) to obtain the Nth distance L between the two. N ; N is equal to 2; According to the following relations 1 and 2, the specific values ​​of the coordinates of the second origin P2 mapped to the first coordinate system are obtained; The first relationship is: initial distance L 0 , the distance between the vehicle-side communication device (D) and the ground-side communication device (E) in the first coordinate system; The second relationship is: the Nth distance L N , the distance between the vehicle-end communication device (D) and the ground-end communication device (E) in the first coordinate system after each movement.

2. The wireless charging vehicle guidance and positioning method according to claim 1, It is characterized in that The coordinates of the ground communication device (E) in the second coordinate system are (A M ,B M ,C M ); The coordinates of the second origin P2 mapped to the first coordinate system are (A P ,B P ,C P ), the coordinates of the ground communication device (E) mapped to the first coordinate system are: [(A P +A M ·cosθ+B M ·sinθ),(B P +B M ·cosθ-A M ·sinθ),(C M +C P )]。 3. The wireless charging vehicle guidance and positioning method according to claim 2, It is characterized in that The first relationship is: Formula 1: L 0 2 = [(A P + A M · cosθ + B M · sinθ) - 0] 2 + [(B P + B M · cosθ - A M · sinθ) - 0] 2 + [(C P + C M ) - 0] 2 ; The second relationship is: Formula 2: L N 2 = {[A P +(A m +A 2N )·cosθ+(B m +B 2N )·sinθ]-A 1N} 2 + {[B P +(B m +B 2N )·cosθ-(A m +A 2N )·sinθ]-B 1N} 2 + [(C P +C M ) - 0] 2 ; A 1N is the moving distance of the vehicle-side communication device (D) on the horizontal axis X1 in the first coordinate system after the transmitter moves N times; B 1N is the moving distance of the vehicle-side communication device (D) on the vertical axis Y1 in the first coordinate system after the transmitter moves N times; A 2N is the moving distance of the ground communication device (E) on the horizontal axis X2 in the second coordinate system after the transmitter moves N times; B 2N It is the moving distance of the ground communication device (E) on the vertical axis Y2 in the second coordinate system after the transmitting end moves N times.

4. The wireless charging vehicle guidance and positioning method according to any one of claims 1 to 3, It is characterized in that Each time the Nth distance L is obtained N When the coordinates of the vehicle-side communication device (D) in the first coordinate system are obtained, the coordinates of the ground communication device in the second coordinate system are also obtained, and the coordinates of the ground communication device in the first coordinate system are obtained according to the coordinate mapping relationship.

5. The wireless charging vehicle guidance and positioning method according to claim 4, It is characterized in that The coordinates of the vehicle-side communication device (D) in the first coordinate system are (A 1N ,B 1N ,0); at the same time, the coordinates of the ground communication device in the second coordinate system are (A m +A 2N ,B m +B 2N , C M ).

6. The wireless charging vehicle guidance and positioning method according to claim 3, It is characterized in that When N=2, the formula 2 is divided into: Formula 2.1: L 1 2 = {[A P + (A m + A 21 )·cosθ + (B m + B 21 )·sinθ] - A 11} 2 + {[B P + (B m + B 21 )·cosθ - (A m + A 21 )·sinθ] - B 11} 2 + [(C P + C M ) - 0] 2 ; Formula 2.2: L 2 2 = {[A P +(A m +A 22 )·cosθ+(B m +B 22 )·sinθ]-A 12} 2 + {[B P +(B m +B 22 )·cosθ-(A m +A 22 )·sinθ]-B 12} 2 + [(C P +C M ) - 0] 2 .

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