Load positioning method and system of planar array type wireless power transmission system

Abstract

The invention provides a load positioning method and system for a planar array type wireless power transmission system. The load positioning method comprises a self-adaptive region division positioning step and a receiving coil positioning step, according to the preset positioning precision, the area where the receiving coil is randomly placed is divided, the optimal reference point of each area is dynamically optimized, the current variation of the transmitting coil when the receiving coil is located at the to-be-positioned point and the optimal reference point is compared through current coil detection, and the variation of the corresponding coordinate is determined; and determining a reference point in the to-be-positioned area, comparing the current similarity of the receiving coil at the to-be-positioned point and the reference point, and calculating to obtain the coordinate of the to-be-positioned point. The device has the advantage of being simple in structure, meanwhile, the load position of the receiving coil can be accurately positioned, the device is suitable for application occasions with different positioning areas and positioning precision, and the problem that the transmission performance of an unmanned aerial vehicle is reduced due to load position deviation in the wireless power transmission system process is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless power transmission, and in particular, relates to a load positioning method and system for a planar array type wireless power transmission system. Background Art

[0002] Currently, wireless charging technology for drones is widely used in various military and civilian drones. Wireless charging platforms can simultaneously charge multiple drones, improving their endurance and efficiency. During charging, unforeseen misalignment of the primary and secondary coils can significantly impact the system's transmission power and efficiency. Therefore, improving the misalignment tolerance of wireless power transfer systems is crucial to ensuring continuous power supply and stable operation of drones.

[0003] In order to improve the system's anti-offset capability, many studies have been conducted to improve the problems caused by coil offset. These studies mainly focus on optimizing the magnetic coupling mechanism, improving the compensation network, tracking the resonant frequency, etc., but these methods all increase the complexity of the system to varying degrees.

[0004] For example, the patent document "A Method for Positioning the Receiving Coil of a Wireless Power Transmission System" (CN115276272A) discloses a planar transmitting coil and receiving coil coupling mechanism for wireless power transmission, a BP neural network coil positioning model, and a BP neural network coil positioning model optimization method. It can achieve the positioning of the receiving coil, stabilize the wireless power transmission process, and reduce the fluctuation of transmission power. However, the structure is relatively complex, the application scenarios are limited, and the positioning is not accurate enough.

[0005] When the transmitter of a wireless power transmission system expands from a conventional single-coil structure to a planar array coil structure, the system's adjustable parameters and flexibility are greatly increased. Furthermore, by adjusting the current phase of the planar array coil, the magnetic field focus position above the array coil can be controlled to achieve power orientation, thereby resolving the problem of system performance degradation caused by the shift of the receiving coil in the conventional single-coil structure. This provides new insights into the research of anti-drift in wireless power transmission systems. However, when the original secondary coil size of the drone charging platform is significantly asymmetric, the planar array system needs to track the position of the secondary coil and achieve power orientation to ensure the system's transmission performance, thus necessitating research on load positioning.

[0006] The patent document "A Method for Precise Positioning of Planar Array Coils in a Wireless Power Transmission System" (CN115378145A) discloses a coupling mechanism for a planar transmitting coil and receiving coil for wireless power transmission, a method for precise positioning of the transmitting coil, and a method for the positioning accuracy Δdm required by the system. This method reduces the fluctuation of transmission power during wireless power transmission caused by changes in the positions of the receiving coil and the transmitting coil, thereby improving the stability of wireless charging. However, the expression and process of correcting the positioning area according to the optimization process are unclear, the possibility of programming implementation is still lacking, and the reliability and response speed are low.

[0007] Therefore, the present invention proposes a load positioning method for a planar array wireless power transmission system to achieve accurate positioning of the load position. Summary of the Invention

[0008] In view of the defects in the prior art, the object of the present invention is to provide a load positioning method and system for a planar array type wireless power transmission system.

[0009] The load positioning method of the planar array type wireless power transmission system provided by the present invention includes:

[0010] Adaptive area division and positioning steps: Based on the preset positioning accuracy, the area where the receiving coils are randomly placed is divided, and the area is refined and dynamically optimized to obtain the best reference point;

[0011] Receiving coil positioning step: compare the current similarity of the receiving coil at the point to be positioned and the best reference point, and calculate the coordinates of the point to be positioned.

[0012] Preferably, the adaptive area division and positioning step includes:

[0013] Step S1: Starting from the boundary x=a of the area to be located, search for the best reference point on the y-axis and the area boundary;

[0014] Step S2: Starting from the boundary y=b of the area to be located, search for the best reference point on the x-axis and the area boundary;

[0015] Step S3: Determine the region boundaries based on the x-axis and y-axis regions, and obtain the first region and the best reference point;

[0016] Step S4: preliminarily divide the area to be positioned using the area boundary;

[0017] Step S5: Refine the initially divided area;

[0018] Step S6: traverse the entire area to be positioned, divide it, and find the best reference point.

[0019] In the receiving coil positioning step, the coordinate deviation of the point to be positioned and the best reference point is calculated based on the current difference of the transmitting coil when the receiving coil is at the best reference point and the point to be positioned, and the coordinates of the point to be positioned are calculated in combination with the coordinate value of the best reference point.

[0020] Preferably, the optimal reference point O on the y-axis in step S1 ref There are σ points on the left side and τ points on the right side, satisfying:

[0021]

[0022]

[0023] Among them, O Lp Indicates the best reference point O ref The p-th point on the left, p = 1, 2, ..., σ;

[0024] O Rq Indicates positioning reference point O ref The qth point on the right, q = 1, 2, ..., τ;

[0025] Δd y Indicates the change in the vertical coordinate;

[0026] Δd m Indicates positioning accuracy;

[0027] l indicates the actual distance.

[0028] The area boundary of the y-axis is the best reference point O on the right side. ref The nth point is the best reference point O ref Right side satisfied The last point.

[0029] In step S2, the boundary is defined as y=b, and the search method is the same as that for searching the optimal reference point on the y-axis and the region boundary.

[0030] The boundaries of the first region are boundary x=a, boundary y=b, a y-axis region boundary, and an x-axis region boundary.

[0031] The optimal reference point of the first area is the coincidence point on the x-axis and the y-axis.

[0032] Preferably, in step S4, the current difference between the transmitting coils of the next area and the first area is compared. If the current difference is greater than a rated threshold, step S5 is executed; if the current difference is less than or equal to the rated threshold, step S6 is executed.

[0033] The size of the next area differs from that of the first area by less than or equal to a set value.

[0034] In step S5, steps S1 to S3 are executed starting from the upper left corner of the next area to obtain an area that meets the positioning accuracy and an optimal reference point. The current difference of the transmitting coil is compared in the remaining part of the next area. If the current difference is less than or equal to the rated threshold, step S6 is executed. If the current difference is greater than the rated threshold, step S5 is repeated until the optimal reference point cannot be found.

[0035] In step S6, the optimal reference point is searched and the area to be positioned is divided according to the positioning algorithm.

[0036] Preferably, the receiving coil positioning step includes:

[0037] The variation curve of the relationship between the current of the transmitting coil and the coordinates of the receiving coil is obtained through the simulation equivalent model of the planar array coil.

[0038] A simplified coupling model of the planar array coil is constructed, and the coordinate information of the optimal reference point and the corresponding transmitting coil current information are established in the database.

[0039] The information of the transmitting coil current of the point to be located is compared with the information of the current of the best reference point for similarity. ij To the positioning point O s The current change ΔI caused by the change of the vertical coordinate at is:

[0040]

[0041] The current Euclidean distance is:

[0042]

[0043] The vertical axis changes to:

[0044]

[0045] The change of the horizontal axis is:

[0046]

[0047] Where Δd y Indicates the change of vertical coordinate;

[0048] Indicates point O ij The vertical coordinate value of

[0049] Indicates point O s The vertical coordinate value of

[0050] ΔI t () represents the current change of the tth transmitting coil;

[0051] Indicates point O ij The tth transmitting coil current value;

[0052] Indicates point O s The tth transmitting coil current value;

[0053] K y , K x Both represent simplified constant coefficients.

[0054] According to the coordinate information of the best reference point, the coordinates of the point to be located are calculated.

[0055] According to the present invention, a load positioning system for a planar array type wireless power transmission system is provided, comprising:

[0056] Adaptive area division and positioning module: divides the area to be positioned of the receiving coil according to the preset positioning accuracy, refines the area, and dynamically optimizes to obtain the best reference point;

[0057] Receiving coil positioning module: compares the current similarity of the receiving coil at the point to be positioned and the best reference point, and calculates the coordinates of the point to be positioned.

[0058] Preferably, the adaptive area division and positioning module includes:

[0059] Module M1, starting from the boundary x=a of the area to be located, searches for the best reference point on the y-axis and the area boundary;

[0060] Module M2, starting from the boundary y=b of the area to be located, searches for the best reference point on the x-axis and the area boundary;

[0061] Module M3, determines the region boundaries based on the region boundaries of the x and y axes, and obtains the first region and the best reference point;

[0062] Module M4: preliminary division of the area to be positioned using the area boundary;

[0063] Module M5: refine the area after preliminary division;

[0064] Module M6: traverse the entire area to be positioned, divide it and find the best reference point.

[0065] The receiving coil positioning module calculates the coordinate deviation of the point to be positioned and the optimal reference point based on the current difference of the transmitting coil when the receiving coil is at the optimal reference point and the point to be positioned, and calculates the coordinates of the point to be positioned in combination with the coordinate value of the optimal reference point.

[0066] Preferably, the optimal reference point O on the y-axis in the module M1 refThere are σ points on the left side and τ points on the right side, satisfying:

[0067]

[0068] Among them, O Lp Indicates the best reference point O ref The p-th point on the left, p = 1, 2, ..., σ;

[0069] O Rq Indicates positioning reference point O ref The qth point on the right, q = 1, 2, ..., τ;

[0070] Δd y Indicates the change in the vertical coordinate;

[0071] Δd m Indicates positioning accuracy;

[0072] l indicates the actual distance.

[0073] The area boundary of the y-axis is the best reference point O on the right side. ref The nth point is the best reference point O ref Right side satisfied The last point.

[0074] In the module M2, the boundary is defined as y=b, and the search method is the same as that for searching the optimal reference point on the y-axis and the region boundary.

[0075] The boundaries of the first region are boundary x=a, boundary y=b, a y-axis region boundary, and an x-axis region boundary.

[0076] The optimal reference point of the first area is the coincidence point on the x-axis and the y-axis.

[0077] Preferably, the module M4 compares the current difference between the transmitting coils of the next area and the first area. If the current difference is greater than the rated threshold, the module M5 is triggered; if the current difference is less than or equal to the rated threshold, the module M6 is triggered.

[0078] The size of the next area differs from that of the first area by less than or equal to a set value.

[0079] In the module M5, modules M1 to M3 are triggered starting from the upper left corner of the next area to obtain an area that meets the positioning accuracy and an optimal reference point. The current difference of the transmitting coil is compared in the remaining part of the next area. If the current difference is less than or equal to the rated threshold, module M6 is triggered. If the current difference is greater than the rated threshold, module M5 is repeatedly triggered until the optimal reference point cannot be found.

[0080] In module M6, the optimal reference point is searched and the area to be positioned is divided according to the positioning algorithm.

[0081] Preferably, the receiving coil positioning module includes:

[0082] The variation curve of the relationship between the current of the transmitting coil and the coordinates of the receiving coil is obtained through the simulation equivalent model of the planar array coil.

[0083] A simplified coupling model of the planar array coil is constructed, and the coordinate information of the optimal reference point and the corresponding transmitting coil current information are established in the database.

[0084] The information of the transmitting coil current of the point to be located is compared with the information of the current of the best reference point for similarity. ij To the positioning point O s The current change ΔI caused by the change of the vertical coordinate at is:

[0085]

[0086] The current Euclidean distance is:

[0087]

[0088] The vertical axis changes to:

[0089]

[0090] The change of the horizontal axis is:

[0091]

[0092] Where Δd y Indicates the change of vertical coordinate;

[0093] Indicates point O ij The vertical coordinate value of

[0094] Indicates point O s The vertical coordinate value of

[0095] ΔI t () represents the current change of the tth transmitting coil;

[0096] Indicates point O ij The tth transmitting coil current value;

[0097] Indicates point O s The tth transmitting coil current value;

[0098] K y , K x Both represent simplified constant coefficients.

[0099] According to the coordinate information of the best reference point, the coordinates of the point to be located are calculated.

[0100] Compared with the prior art, the present invention has the following beneficial effects:

[0101] 1. The present invention achieves precise positioning of the receiving coil load position by adaptively dividing the target area according to the preset positioning accuracy, fully considers the conditions for further refinement of the area, improves the programming feasibility, and provides an implementation path for realizing position movement, improving transmission performance and power directional strategy.

[0102] 2. The present invention only needs to collect the current of the transmitting coil, without the need for additional detection coils or position sensors, and does not require communication with the receiving side, thus optimizing the workflow. It has the advantage of a simple structure and is suitable for applications with different positioning areas and positioning accuracies.

[0103] 3. The present invention can track the position of the secondary coil and achieve power orientation, solving the problem of load position deviation in wireless power transmission systems faced by drones, which leads to decreased transmission performance. It also improves technical performance in terms of reliability and response speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0104] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0105] Figure 1 The figure is a flow chart of a load positioning method for a planar array wireless power transmission system.

[0106] Figure 2 Schematic diagram of the equivalent model for planar array coil simulation.

[0107] Figure 3 Schematic diagram of the load positioning process of the planar array wireless power transmission system.

[0108] Figure 4 Schematic diagram of a simplified coupling model for a planar array coil.

[0109] Figure 5 Schematic diagram of the change curve of coil current value and y-axis coordinate value under different x-coordinate values.

[0110] Figure 6 Schematic diagram for selecting positioning reference points.

[0111] Figure 7 A schematic diagram of all positioning areas and positioning reference points within the areas.

[0112] Figure 8Schematic diagram of positioning simulation and experimental results. DETAILED DESCRIPTION

[0113] The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several changes and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0114] In order to solve the problem of load position deviation in wireless power transmission system faced by UAVs, which leads to the degradation of transmission performance, a load positioning method for planar array wireless power transmission system is proposed according to the present invention. The method can be implemented in all areas of the positioning point, including the case of regional division. No additional detection coils or position sensors are required. Only by establishing a relationship model between the transmitting coil current and the receiving coil coordinates, the coordinate calculation formula can be derived, thereby achieving accurate positioning of the load position and providing a path for realizing position movement to improve transmission performance and power directional strategy. Specifically, Figure 1 For example, it includes: a receiving coil positioning step and an adaptive area division positioning step.

[0115] Adaptive area division and positioning steps: According to the preset positioning accuracy, the area where the receiving coils are randomly placed is divided, and the best reference point of each area is dynamically optimized.

[0116] Specifically, the adaptive area division and positioning step improves the possibility of programming implementation. The key lies in determining the best positioning reference point and dividing the corresponding area boundaries, thereby improving technical performance in terms of reliability and response speed. Figure 3 For example, including:

[0117] Step S1: Starting from the initial boundary of the area to be located, search for the best reference point on the y-axis;

[0118] Specifically, start searching for reference points from the boundary x=a of the area to be located. Suppose a certain positioning reference point O ref There are σ points on the left side and τ points on the right side, then all points on the left side of this point must satisfy:

[0119]

[0120] Among them, O Lp Indicates the best reference point O ref For all points on the left, p = 1, 2, …, σ.

[0121] Continue searching among all the positioning reference points that satisfy the above equation and select the points that satisfy the most of the following conditions:

[0122]

[0123] Among them, O Rq Indicates positioning reference point O ref For all points on the right, q = 1, 2, …, τ.

[0124] At this time, the selected point O ref The best reference point on the y-axis where x=a.

[0125] Step S2, determining the region boundary of the y-axis;

[0126] Set the best reference point O ref The right side does not satisfy the condition starting from point n+1 This indicates that the region boundary points on the y-axis are the n points to the right of the optimal reference point, which means that the right boundary of the region is determined.

[0127] In more preferred embodiments, in the area to be positioned, on a horizontal axis where x is a fixed value, 6 points (O1, O2, O3, O4, O5, O6) are divided according to the step size s, such as Figure 6 shown.

[0128] If the positioning reference point is selected as O3, and points O2, O4, and O5 meet This means that at the current reference point, the positioning accuracy of the points to be positioned O2, O4, and O5 on the y-axis meets the set value Δd m .

[0129] Among them, l O3-> l O2 、l O3-> l O4 、l O3-> l O5 They represent the actual distances from O3 to O2, O4, and O5, and their values ​​are s, s, and 2s respectively.

[0130] Points O1 and O6 meet This indicates that points O2 and O6 do not meet the set positioning accuracy Δd. m .

[0131] Step S3: Starting from the initial boundary of the area to be located, determine the best reference point and area boundary on the x-axis;

[0132] Similar to step S1-2, the reference point and the region boundary of the x-axis are searched starting from the boundary y=b of the region to be located to determine the lower boundary of the region.

[0133] Step S4: determining the boundary of the region and the best reference point within the region;

[0134] Through steps S1 to S3, the lower boundary of the x-axis region and the right boundary of the y-axis region are obtained, and combined with the initial boundary of the region to be located, the first region A is obtained. 11 In A 11 The above method is used to search for the best reference point, and the coincident point on the x-axis and y-axis is used as the best reference positioning point in the area.

[0135] Step S5: preliminarily divide the entire area to be located using the determined area boundaries;

[0136] by Figure 3 For example, the first area A 11 After confirmation, the next area A 12 When dividing, the upper, lower and left initial boundaries of the region have been determined. If region A 12 Compared with the previous area A 11 The current of each transmitting coil is quite different and cannot be compared with the previous area A. 11 To find an optimal reference point that satisfies positioning accuracy within an area of ​​similar size, it is necessary to 12 To further refine, execute step S6. If area A 12 Compared with the previous area A 11 If the currents of the transmitting coils are not much different, step S7 is executed.

[0137] In more preferred embodiments, the accuracy Δd is set m =10mm, a total of 34 positioning areas are divided. Figure 7 The white area in the middle is the area with smaller current differences in the transmitting coil, and the gray area is the area with larger current differences in the transmitting coil. To achieve the required positioning accuracy, the gray area is refined.

[0138] Step S6: Region refinement. If an optimal reference point that satisfies positioning accuracy cannot be found within the initially divided region, the region needs to be refined.

[0139] Repeat steps S1-2 starting from the upper left corner of the region to obtain the best reference point on the y-axis and the y-axis region boundary, that is, to determine the right boundary of the second region. Then execute steps S3-4 to obtain the region and the best reference point that meet the positioning accuracy. This region is defined as A 121 In A 12 The search for the best reference point is continued in the remaining area. Depending on the current difference of each transmitting coil, various situations may occur. If an optimal reference point that meets the positioning accuracy requirements can be found in the remaining area, the area is defined as A. 122 If the remaining area still needs to be re-divided, repeat step S6 to refine the area. 12 By refining the area, A121 , A 122 , A 123 Three sub-areas.

[0140] In more preferred embodiments, area A 21 The two sub-areas are named A 211 and A 212 The box points in the area represent the optimal reference points for positioning within the area. The reason why the gray area is asymmetrically distributed throughout the entire positioning area is that in the finite element simulation, the four transmitting coils are not in the same plane, but are placed overlappingly with a certain height difference.

[0141] Step S7: Complete the division of the entire area and the search for the optimal reference point. Traverse the entire area to be located, divide the entire area to be located, and search for the optimal reference point.

[0142] According to the positioning algorithm, the best reference point search and area division are carried out in the positioning area. The results are given by Figure 7 shown.

[0143] Receiving coil positioning step: by determining a reference point in the area to be positioned, and by comparing the similarity of the current of the receiving coil at the point to be positioned and the reference point, the coordinates of the point to be positioned are calculated.

[0144] Specifically, in step S8, the coordinates of the point to be located are calculated. Based on the current changes in the array coil when the receiving coil is at the optimal reference point and the point to be located, the coordinate deviation between the point to be located and the optimal reference point is calculated. Combined with the coordinate values ​​of the optimal reference point, the coordinates of the point to be located are then calculated.

[0145] Specifically, the fitting data source, fitting function expression and positioning step derivation process are given. By fitting the changing curve of the relationship between the current of the transmitting coil and the coordinates of the receiving coil, combined with the difference in the transmitting coil current when the receiving coil is located at the optimal reference point and the point to be positioned, the coordinates of the receiving coil are calculated.

[0146] by Figure 2 For example, a curve was obtained by simulating an equivalent model of a planar array coil. The center points of the four transmitting coils are O1, O2, O3, and O4, respectively. The coordinate origin is O1, the center point of transmitting coil 1. The gray area represents the overlapping region of the four coils. The coordinates of the receiving coil center are (a, b). Simulation was performed within the range of -100mm≤a≤229mm and -100mm≤b≤229mm with a step size of l = 5mm, resulting in 4489 coordinate points, or 4489 sets of data. The input voltage is 2V, the frequency is 200kHz, the compensation network is all SS type, and the load is 15Ω.

[0147] Construct a simplified coupling model of a planar array coil to Figure 4For example, A1B1C1D1 is the transmitting coil 1, A2B2C2D2 is the transmitting coil 2, A3B3C3D3 is the transmitting coil 3, and A4B4C4D4 is the transmitting coil 4. There are two receiving coils at arbitrary positions above the array coil, and their center points are O p and O q When the center point of the receiving coil is at O p At point 1, the current of the four transmitting coils is I p ={I p1 ,I p2 ,I p3 ,I p4}, when the center point of the receiving coil is at O q At point 1, the current of the four transmitting coils is I q ={I q1 ,I q2 ,I q3 ,I q4}. In order to describe the center point of the receiving coil from O p Point to O q The current change of the point, take the Euclidean distance of the current between the two points, record δ p-＞q , its expression is:

[0148]

[0149] For the above formula, when δ p->q =0, I must be satisfied p1 =I q1 , I p2 =I q2 , I p3 =I q3 , I p4 =I q4 , I p1 ,I p2 ,I p3 ,I p4 The center points of transmitting coils 1, 2, 3, and 4 are located at O p The current at point I q1 , I q2 , I q3 , I q4 The center points of transmitting coils 1, 2, 3, and 4 are located at O q The current at point O p Dot and O q Points overlap.

[0150] Therefore, an optimal reference point is determined in the area to be positioned, and the coordinate information of the optimal reference point and the corresponding information of the four transmitting coil currents, i.e., I q1 , I q2 , I q3, I q4 , establish it into a database, compare the similarity of the four transmitting coil current information of the point to be located with the current information of the best reference point, and finally calculate the coordinates of the point to be located based on the coordinate information of the best reference point. In the rectangular coordinate system established by the simplified coupling model of the planar array coil, the curve of the change of the coil current value and the y-axis coordinate value under different x-coordinate values ​​is given by Figure 5 shown.

[0151] In more preferred embodiments, the curve of current and y-axis coordinate value is fitted by using the Curve Fitting toolbox in MATLAB to obtain the following function:

[0152] I(y)=a0+a1 cos(ωy)+b1 sin(ωy)+a2cos(2ωy)+b2sin(2ωy)+a3 cos(3ωy)+b3 sin(3ωy)+a4cos(4ωy)+b4sin(4ωy)

[0153] Among them, a0, a1, b1, a2, b2, a3, b3, a4, b4, and ω are constant coefficients related to the x-axis coordinate value. Find the derivative function:

[0154] I′(y)=-a1ωsin(ωy)+b1ωcos(ωy)-2a2ωsin(2ωy)+2b2ωcos(2ωy)-3a3ωsin(3ωy)+3b3ωcos(3ωy)-4a4ωsin(4ωy)+4b4ωcos(4ωy)

[0155] The current change caused by the change in the y-axis coordinate is approximately calculated as:

[0156] I(y+Δy)≈I(y)+I′(y)Δy

[0157] Therefore, in area A ij The best reference point O ij To the positioning point O s The current change ΔI caused by the change of the vertical coordinate at is:

[0158]

[0159] Where Δd y Indicates reference point O ij To the positioning point O s The vertical coordinate changes, Indicates point O ij The vertical coordinate value of Indicates point O s The vertical axis value of , I() represents the fitting function.

[0160] therefore:

[0161]

[0162] For ease of analysis, the formula is simplified:

[0163]

[0164] Among them, K y Represents the simplified constant coefficient. At this time, the current changes of the four transmitting coils are:

[0165]

[0166] The change of current at two points is expressed as:

[0167]

[0168] The current Euclidean distance between two points is:

[0169]

[0170] Reference point O ij To the positioning point O s The vertical coordinate changes to:

[0171]

[0172] The same analysis process as above, the change of the horizontal coordinate from the reference point Oij to the point to be located Os is:

[0173]

[0174] Among them, K x represents the simplified constant coefficient.

[0175] To ensure high positioning accuracy, it is necessary to divide different positioning areas and find reference points in each area. The required positioning accuracy Δd m The number and size of the positioning zones and the reference points within them are determined. A fixed optimization algorithm is used throughout the entire process, streamlining the workflow and eliminating repeated error correction and revision work. This algorithm is highly adaptable, meaning that when array system parameters change, only the algorithm input parameters need to be modified, maintaining the complexity of the entire workflow. This improves project feasibility and overall efficiency.

[0176] Through current coil detection, the change in the transmitting coil current when the receiving coil is at the point to be positioned and the optimal reference point is compared to determine the change in the corresponding coordinates. Only the current of the transmitting coil needs to be collected, without the need for additional detection coils or position sensors, and without the need for communication with the receiving side, thereby achieving precise positioning of the receiving coil.

[0177] In more preferred examples, the effectiveness of the proposed method is verified through simulation and experiments. The simulation model of the system established in ANSYS is used to verify the results of the 329mm×329mm positioning area division. Figure 7 The coordinates of 10 positioning areas and one point to be positioned in the area of ​​34 positioning areas are obtained. The positioning algorithm and simulation current data are used to determine the best reference point and obtain the simulation positioning coordinates. A coil positioning experimental platform is built. By measuring the current values ​​of 10 points to be positioned randomly selected during the simulation process and the best reference point in the corresponding area, the coordinate values ​​of the point to be positioned are calculated by the positioning algorithm to verify the effectiveness of the proposed positioning algorithm. The positioning simulation and experimental results are shown in Figure 2. Figure 8 As shown in the figure, the triangle represents the actual coordinates of the point to be located, the circle represents the simulated coordinates of the point to be located, and the square represents the simulated coordinates of the point to be located. The results show that the positioning coordinate errors of the 10 randomly selected points are all less than the preset positioning accuracy of 10mm. The average positioning error of the 10 points in the simulation is 4.96mm, and the average error percentage is 1.07%, meeting the requirements of high-precision positioning. The experimental average positioning error of the 10 points is 9.98mm, which is less than the preset positioning accuracy of 10mm, and the average error percentage is 2.15%.

[0178] The experimental results show that within an area of ​​329mm×329mm, the average positioning error is 9.98mm, which meets the preset positioning accuracy of 10mm. Compared with the simulation results, the error is slightly larger. This is due to coil winding errors, operation errors, measurement errors and other reasons in the experiment, but it also basically meets the requirements of high-precision positioning.

[0179] The present invention also provides a load positioning system for a planar array type wireless power transmission system. The load positioning system of the planar array type wireless power transmission system can be implemented by executing the process steps of the load positioning method of the planar array type wireless power transmission system. That is, those skilled in the art can understand the load positioning method of the planar array type wireless power transmission system as a preferred implementation of the load positioning system of the planar array type wireless power transmission system.

[0180] According to the present invention, a load positioning system for a planar array type wireless power transmission system is provided, comprising:

[0181] Adaptive area division and positioning module: divides the area to be positioned of the receiving coil according to the preset positioning accuracy, refines the area, and dynamically optimizes to obtain the best reference point;

[0182] Receiving coil positioning module: compares the current similarity of the receiving coil at the point to be positioned and the best reference point, and calculates the coordinates of the point to be positioned.

[0183] In more preferred embodiments, the adaptive area division and positioning module includes:

[0184] Module M1, starting from the boundary x=a of the area to be located, searches for the best reference point on the y-axis and the area boundary;

[0185] Module M2, starting from the boundary y=b of the area to be located, searches for the best reference point on the x-axis and the area boundary;

[0186] Module M3, determines the region boundaries based on the region boundaries of the x and y axes, and obtains the first region and the best reference point;

[0187] Module M4: preliminary division of the area to be positioned using the area boundary;

[0188] Module M5: refine the area after preliminary division;

[0189] Module M6: traverse the entire area to be positioned, divide it and find the best reference point.

[0190] The receiving coil positioning module calculates the coordinate deviation of the point to be positioned and the optimal reference point based on the current difference of the transmitting coil when the receiving coil is at the optimal reference point and the point to be positioned, and calculates the coordinates of the point to be positioned in combination with the coordinate value of the optimal reference point.

[0191] In more preferred embodiments, the optimal reference point O on the y-axis in the module M1 is ref There are σ points on the left side and τ points on the right side, satisfying:

[0192]

[0193] Among them, O Lp Indicates the best reference point O ref The p-th point on the left, p = 1, 2, ..., σ;

[0194] O Rq Indicates positioning reference point O ref The qth point on the right, q = 1, 2, ..., τ;

[0195] Δd y Indicates the change in the vertical coordinate;

[0196] Δd m Indicates positioning accuracy;

[0197] l indicates the actual distance.

[0198] The area boundary of the y-axis is the best reference point O on the right side. ref The nth point is the best reference point O ref Right side satisfied The last point.

[0199] In the module M2, the boundary is defined as y=b, and the search method is the same as that for searching the optimal reference point on the y-axis and the region boundary.

[0200] The boundaries of the first region are boundary x=a, boundary y=b, a y-axis region boundary, and an x-axis region boundary.

[0201] The optimal reference point of the first area is the coincidence point on the x-axis and the y-axis.

[0202] In more preferred examples, the module M4 compares the current difference between the transmitting coils of the next area and the first area. If the current difference is greater than the rated threshold, the module M5 is triggered; if the current difference is less than or equal to the rated threshold, the module M6 is triggered.

[0203] The size of the next area differs from that of the first area by less than or equal to a set value.

[0204] In the module M5, modules M1 to M3 are triggered starting from the upper left corner of the next area to obtain an area that meets the positioning accuracy and an optimal reference point. The current difference of the transmitting coil is compared in the remaining part of the next area. If the current difference is less than or equal to the rated threshold, module M6 is triggered. If the current difference is greater than the rated threshold, module M5 is repeatedly triggered until the optimal reference point cannot be found.

[0205] In module M6, the optimal reference point is searched and the area to be positioned is divided according to the positioning algorithm.

[0206] In more preferred embodiments, the receiving coil positioning module includes:

[0207] The variation curve of the relationship between the current of the transmitting coil and the coordinates of the receiving coil is obtained through the simulation equivalent model of the planar array coil.

[0208] A simplified coupling model of the planar array coil is constructed, and the coordinate information of the optimal reference point and the corresponding transmitting coil current information are established in the database.

[0209] The information of the transmitting coil current of the point to be located is compared with the information of the current of the best reference point for similarity. ij To the positioning point O s The current change ΔI caused by the change of the vertical coordinate at is:

[0210]

[0211] The current Euclidean distance is:

[0212]

[0213] The vertical axis changes to:

[0214]

[0215] The change of the horizontal axis is:

[0216]

[0217] Where Δd y Indicates the change of vertical coordinate;

[0218] Indicates point O ij The vertical coordinate value of

[0219] Indicates point O s The vertical coordinate value of

[0220] ΔI t () represents the current change of the tth transmitting coil;

[0221] Indicates point O ij The tth transmitting coil current value;

[0222] Indicates point O s The tth transmitting coil current value;

[0223] K y , K x Both represent simplified constant coefficients.

[0224] According to the coordinate information of the best reference point, the coordinates of the point to be located are calculated.

[0225] Those skilled in the art will appreciate that, in addition to implementing the system and its various devices, modules, and units provided by the present invention in purely computer-readable program code, it is entirely possible to implement the same functions of the system and its various devices, modules, and units provided by the present invention in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system and its various devices, modules, and units provided by the present invention can be considered a hardware component, and the devices, modules, and units included therein for implementing various functions can also be considered as structures within the hardware component; the devices, modules, and units for implementing various functions can also be considered as both software modules implementing the method and structures within the hardware component.

[0226] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A load positioning method for a planar array wireless power transmission system, characterized in that: include: Adaptive area division and positioning steps: According to the preset positioning accuracy, the area to be positioned of the receiving coil is divided and refined, and the optimal reference point is obtained through dynamic optimization; Receiving coil positioning step: compare the current similarity of the receiving coil at the point to be positioned and the best reference point, and calculate the coordinates of the point to be positioned.

2. The load positioning method of the planar array type wireless power transmission system according to claim 1, characterized in that: The adaptive area division and positioning step includes: Step S1: Starting from the boundary x=a of the area to be located, search for the best reference point on the y-axis and the area boundary; Step S2: Starting from the boundary y=b of the area to be located, search for the best reference point on the x-axis and the area boundary; Step S3: Determine the region boundaries based on the x-axis and y-axis regions, and obtain the first region and the best reference point; Step S4: preliminarily divide the area to be positioned using the area boundary; Step S5: Refine the initially divided area; Step S6: traverse the entire area to be positioned, divide it and find the best reference point; In the receiving coil positioning step, the coordinate deviation of the point to be positioned and the best reference point is calculated based on the current difference of the transmitting coil when the receiving coil is at the best reference point and the point to be positioned, and the coordinates of the point to be positioned are calculated in combination with the coordinate value of the best reference point.

3. The load positioning method of the planar array type wireless power transmission system according to claim 2, characterized in that: The optimal reference point O on the y-axis in step S1 ref There are σ points on the left side and τ points on the right side, satisfying: Among them, O Lp Indicates the best reference point O ref The p-th point on the left, p = 1, 2, ..., σ; O Rq Indicates positioning reference point O ref The qth point on the right, q = 1, 2, ..., τ; Δd y Indicates the change in the vertical coordinate; Δd m Indicates positioning accuracy; l represents the actual distance; The area boundary of the y-axis is the best reference point O on the right side. ref The nth point is the best reference point O ref Right side satisfied The last point of In step S2, the boundary is defined as y=b, and the search method is the same as searching for the best reference point on the y-axis and the region boundary; The boundaries of the first region are boundary x=a, boundary y=b, y-axis region boundary and x-axis region boundary; The optimal reference point of the first area is the coincidence point on the x-axis and the y-axis.

4. The load positioning method of the planar array type wireless power transmission system according to claim 2, characterized in that: In step S4, the current difference between the transmitting coils of the next area and the first area is compared. If the current difference is greater than the rated threshold, step S5 is executed; if the current difference is less than or equal to the rated threshold, step S6 is executed; The size of the next area is less than or equal to the set value compared with the first area; In step S5, steps S1 to S3 are executed starting from the upper left corner of the next area to obtain an area that meets the positioning accuracy and an optimal reference point. The current difference of the transmitting coil is compared in the remaining part of the next area. If the current difference is less than or equal to the rated threshold, step S6 is executed. If the current difference is greater than the rated threshold, step S5 is repeated until the optimal reference point cannot be found. In step S6, the optimal reference point is searched and the area to be positioned is divided according to the positioning algorithm.

5. The load positioning method of the planar array type wireless power transmission system according to claim 2, characterized in that: The receiving coil positioning step includes: The variation curve of the relationship between the current of the transmitting coil and the coordinates of the receiving coil is obtained through the simulation equivalent model of the planar array coil; Construct a simplified coupling model of the planar array coil and store the coordinate information of the optimal reference point and the corresponding transmitting coil current information in the database; The information of the transmitting coil current of the point to be located is compared with the information of the current of the best reference point for similarity. ij To the positioning point O s The current change ΔI caused by the change of the vertical coordinate at is: The current Euclidean distance is: The vertical axis changes to: The change of the horizontal axis is: Where Δd y Indicates the change of vertical coordinate; Indicates point O s The vertical coordinate value of ΔI t () represents the current change of the tth transmitting coil; Indicates point O ij The tth transmitting coil current value; Indicates point O s The tth transmitting coil current value; K y , K x All represent simplified constant coefficients; According to the coordinate information of the best reference point, the coordinates of the point to be located are calculated.

6. A load positioning system for a planar array wireless power transmission system, characterized in that: include: Adaptive area division and positioning module: divides the area to be positioned of the receiving coil according to the preset positioning accuracy, refines the area, and dynamically optimizes to obtain the best reference point; Receiving coil positioning module: compares the current similarity of the receiving coil at the point to be positioned and the best reference point, and calculates the coordinates of the point to be positioned.

7. The load positioning system of the planar array type wireless power transmission system according to claim 6, characterized in that: The adaptive area division and positioning module includes: Module M1, starting from the boundary x=a of the area to be located, searches for the best reference point on the y-axis and the area boundary; Module M2, starting from the boundary y=b of the area to be located, searches for the best reference point on the x-axis and the area boundary; Module M3, determines the region boundaries based on the region boundaries of the x and y axes, and obtains the first region and the best reference point; Module M4: preliminary division of the area to be positioned using the area boundary; Module M5: refine the area after preliminary division; Module M6: traverse the entire area to be positioned, divide it and find the best reference point; The receiving coil positioning module calculates the coordinate deviation of the point to be positioned and the optimal reference point based on the current difference of the transmitting coil when the receiving coil is at the optimal reference point and the point to be positioned, and calculates the coordinates of the point to be positioned in combination with the coordinate value of the optimal reference point.

8. The load positioning system of the planar array type wireless power transmission system according to claim 7, characterized in that: The optimal reference point O on the y-axis in the module M1 ref There are σ points on the left side and τ points on the right side, satisfying: Among them, O Lp Indicates the best reference point O ref The p-th point on the left, p = 1, 2, ..., σ; O Rq Indicates positioning reference point O ref The qth point on the right, q = 1, 2, ..., τ; Δd y Indicates the change in the vertical coordinate; Δd m Indicates positioning accuracy; l represents the actual distance; The area boundary of the y-axis is the best reference point O on the right side. ref The nth point is the best reference point O ref Right side satisfied The last point of In the module M2, the boundary is defined as y=b, and the search method is the same as that for searching the optimal reference point and region boundary on the y-axis; The boundaries of the first region are boundary x=a, boundary y=b, y-axis region boundary and x-axis region boundary; The optimal reference point of the first area is the coincidence point on the x-axis and the y-axis.

9. The load positioning system of the planar array type wireless power transmission system according to claim 7, characterized in that: The module M4 compares the current difference between the transmitting coils of the next area and the first area. If the current difference is greater than the rated threshold, the module M5 is triggered. If the current difference is less than or equal to the rated threshold, the module M6 is triggered. The size of the next area is less than or equal to the set value compared with the first area; In the module M5, modules M1 to M3 are triggered starting from the upper left corner of the next area to obtain an area that meets the positioning accuracy and an optimal reference point. The current difference of the transmitting coil is compared in the remaining part of the next area. If the current difference is less than or equal to the rated threshold, module M6 is triggered. If the current difference is greater than the rated threshold, module M5 is repeatedly triggered until the optimal reference point cannot be found. In module M6, the optimal reference point is searched and the area to be positioned is divided according to the positioning algorithm.

10. The load positioning system of the planar array type wireless power transmission system according to claim 7, characterized in that: The receiving coil positioning module includes: The variation curve of the relationship between the current of the transmitting coil and the coordinates of the receiving coil is obtained through the simulation equivalent model of the planar array coil; Construct a simplified coupling model of the planar array coil and store the coordinate information of the optimal reference point and the corresponding transmitting coil current information in the database; The information of the transmitting coil current of the point to be located is compared with the information of the current of the best reference point for similarity. ij To the positioning point O s The current change ΔI caused by the change of the vertical coordinate at is: The current Euclidean distance is: The vertical axis changes to: The change of the horizontal axis is: Where Δd y Indicates the change of vertical coordinate; Indicates point O ij The vertical coordinate value of Indicates point O s The vertical coordinate value of ΔI t () represents the current change of the tth transmitting coil; Indicates point O ij The tth transmitting coil current value; Indicates point O s The tth transmitting coil current value; K y , K x All represent simplified constant coefficients; According to the coordinate information of the best reference point, the coordinates of the point to be located are calculated.

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