Wireless charging vehicle and wireless charging method thereof

Abstract

This invention discloses a wireless charging vehicle and a wireless charging method thereof. The wireless charging vehicle includes: a secondary charging plate configured to generate an induced current through a magnetic field generated by a primary charging plate in a wireless charging station, and to charge a battery; a plurality of ultra-wideband (UWB) tags arranged around the vehicle; and a UWB controller configured to execute a wireless charging alignment mode for aligning the secondary charging plate onto the primary charging plate by utilizing sensor values ​​measured using the UWB tags, wherein the UWB controller is configured to calculate the coordinates of the primary charging plate by utilizing line-of-sight (LOS) sensor values ​​of the UWB tags having a line of sight.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of Korean Patent Application No. 10-2021-0101799, filed on August 3, 2021, which is incorporated herein by reference. Technical Field

[0003] This invention relates to a wireless charging vehicle and a wireless charging method thereof. Background Technology

[0004] An electric vehicle charging system is essentially a system that uses electricity from the power grid or energy storage devices to charge the batteries installed in an electric vehicle. Electric vehicle charging systems can take various forms depending on the type of electric vehicle. For example, electric vehicle charging systems can include conductive charging systems using cables or contactless wireless charging systems. Typically, wireless charging in a wireless charging system refers to a method of charging a battery by causing an electric current to flow through electromagnetic induction. The magnetic field generated by the current flowing in the primary coil of the charger induces a current in the secondary coil of the battery, and this induced current charges the battery.

[0005] Wireless charging systems are an essential charging technology when considering the convenience of charging autonomous or electric vehicles. To achieve optimal charging efficiency, precise alignment between the primary charging pad of the wireless charger that transmits power and the secondary charging pad of the vehicle that receives power is essential.

[0006] The above-disclosed content in this background section is only for enhancing the understanding of the background technology of this invention, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0007] Embodiments of the present invention relate to a wireless charging vehicle and a wireless charging method thereof. Specific embodiments relate to a wireless charging vehicle and a wireless charging method thereof for performing positional alignment between the vehicle and a wireless charger.

[0008] Embodiments of the present invention provide a wireless charging vehicle and a wireless charging method thereof that enable accurate alignment between the primary charging board of a wireless charger and the secondary charging board of a vehicle.

[0009] Embodiments of the present invention provide a wireless charging vehicle, comprising: a secondary charging plate that generates an induced current through a magnetic field generated by a primary charging plate of a wireless charging station and charges a battery; a plurality of ultra-wideband (UWB) tags configured to surround the vehicle; and a UWB controller that executes a wireless charging alignment mode for aligning the secondary charging plate onto the primary charging plate by utilizing sensor values ​​measured by the UWB tags, wherein the UWB controller calculates the coordinates of the primary charging plate by utilizing line-of-sight (LOS) sensor values ​​of the UWB tags having a line of sight.

[0010] The UWB controller can compare the UWB signals of each UWB tag and determine the location quadrant of the primary charging board. Based on the location quadrant, it can distinguish between UWB tags with and without line of sight.

[0011] The UWB controller can combine odometer information and LOS sensor values ​​based on the vehicle's movement to update the vehicle's position.

[0012] The UWB controller can update the vehicle position by utilizing extended Kalman filter and particle filter schemes.

[0013] Another embodiment of the present invention provides a wireless charging method for a wireless charging vehicle, the method comprising: comparing UWB signals received by a plurality of UWB tags and determining the location quadrant of a UWB anchor point; calculating the coordinates of the UWB anchor point based on the location quadrant by utilizing the LOS sensor values ​​of a UWB tag with line of sight; and moving towards the UWB anchor point based on the coordinates of the UWB anchor point.

[0014] The wireless charging method may further include combining odometer information and LOS sensor values ​​based on the vehicle's movement to update the vehicle's location.

[0015] The vehicle position can be updated by utilizing extended Kalman filters and particle filter schemes.

[0016] The location of the primary charging board of the wireless charger can be located remotely using UWB sensors applied to the vehicle, and accurate alignment between the primary charging board of the wireless charger and the secondary charging board of the vehicle can be performed. Attached Figure Description

[0017] Figure 1 A wireless charging vehicle according to an embodiment of the present invention is shown.

[0018] Figure 2 A wireless charging station according to an embodiment of the present invention is shown.

[0019] Figure 3 This is a flowchart illustrating a wireless charging method for a wireless charging vehicle according to an embodiment of the present invention.

[0020] Figure 4 The quadrants for determining the location quadrants of UWB anchor points according to embodiments of the present invention are shown.

[0021] Figure 5 A method for calculating UWB anchor point coordinates according to an embodiment of the present invention is shown.

[0022] Figure 6 A method for updating vehicle location based on vehicle movement according to an embodiment of the present invention is shown.

[0023] Figure 7 This is a flowchart illustrating a wireless charging method for a wireless charging vehicle according to another embodiment of the present invention. Detailed Implementation

[0024] Embodiments of the present invention will now be described more fully with reference to the accompanying drawings, which illustrate examples of the invention. Those skilled in the art will recognize that the described embodiments can be modified in various ways without departing from the spirit or scope of the invention.

[0025] The accompanying drawings and descriptions are intended to be illustrative rather than restrictive in nature, and the same reference numerals denote the same elements throughout the specification.

[0026] Unless explicitly stated otherwise, the words “comprising” and variations such as “including” or “containing” shall be understood to imply inclusion of the stated element but not exclusion of any other element.

[0027] Now refer to Figure 1 Describe wireless charging vehicles, refer to Figure 2 Describe a wireless charging station, and refer to... Figures 3 to 7 Describe the wireless charging method for wireless charging vehicles.

[0028] Figure 1 A wireless charging vehicle according to an embodiment of the present invention is shown.

[0029] Reference Figure 1 The wireless charging vehicle 100 includes a secondary charging pad 110, a UWB controller 120, and multiple UWB tags 121, 122, 123, 124, 125, 126, and 127. The wireless charging vehicle 100 may include vehicles that need to be charged, such as electric vehicles, autonomous vehicles, or hybrid vehicles.

[0030] The secondary charging board 110 can be referenced by [the relevant authority / organization]. Figure 2The primary charging plate 210 generates a magnetic field that induces a current, which can charge the battery of the wireless charging vehicle 100. The secondary charging plate 110 can be disposed at the lower part of the vehicle to have an appropriate gap with the primary charging plate 210 when charging the battery. The secondary charging plate 110... Figure 1 The secondary charging pad 110 is shown to be located at the front of the wireless charging vehicle 100, but its location is not limited to this.

[0031] UWB tags 121, 122, 123, 124, 125, 126, and 127 represent sensors that measure distance and direction using UWB technology, a short-range wireless communication protocol. When viewed from above (in a plan view) of the wireless charging vehicle 100, UWB tags 121, 122, 123, 124, 125, 126, and 127 can be arranged around the wireless charging vehicle 100.

[0032] As described above, the first UWB tag 121 can be positioned at the front left of the wireless charging vehicle 100, the second UWB tag 122 can be positioned at the front right of the wireless charging vehicle 100, the third UWB tag 123 can be positioned at the left center of the wireless charging vehicle 100, the fourth UWB tag 124 can be positioned at the right center of the wireless charging vehicle 100, the fifth UWB tag 125 can be positioned at the center rear of the wireless charging vehicle 100, the sixth UWB tag 126 can be positioned at the rear left of the wireless charging vehicle 100, and the seventh UWB tag 127 can be positioned at the rear right of the wireless charging vehicle 100. The positions and number of UWB tags 121, 122, 123, 124, 125, 126, and 127 are not limited; they can be positioned in multiple locations as needed, and can also be added or deleted as required.

[0033] The UWB controller 120 executes a wireless charging alignment mode by utilizing sensor values ​​measured by UWB tags 121, 122, 123, 124, 125, 126, and 127. The wireless charging alignment mode can be referenced... Figures 3 to 7 As described later in this specification.

[0034] Figure 2 A wireless charging station according to an embodiment of the present invention is shown.

[0035] Reference Figure 2 The wireless charging station 200 includes a primary charging plate 210, a wireless charger 220, and at least one UWB anchor 221.

[0036] The primary charging plate 210 can receive power from the power grid or an energy storage device and can generate a magnetic field for charging the wireless charging vehicle 100. The primary charging plate 210 can be installed on the ground of the parking lot 211, so that the primary charging plate 210 can face the secondary charging plate 110 of the wireless charging vehicle 100 in the parking lot 211.

[0037] The wireless charger 220 can control the power supplied to the primary charging plate 210 and can provide the user with charging information of the wireless charging vehicle 100.

[0038] At least one UWB anchor point 221 can periodically transmit UWB signals to guide the wireless charging vehicle 100 to its charging position, or can transmit UWB signals upon request from the wireless charging vehicle 100. At least one UWB anchor point 221 can be positioned on at least one edge of the primary charging pad 210, the wireless charger 220, and the parking lot 211. At least one UWB anchor point 221 can be positioned appropriately to guide the wireless charging vehicle 100 to its charging position, and the position of the UWB anchor point 221 is unrestricted.

[0039] Figure 3 This is a flowchart illustrating a wireless charging method for a wireless charging vehicle according to an embodiment of the present invention. Figure 4 The quadrants for determining the location quadrants of UWB anchor points according to embodiments of the present invention are shown. Figure 5 A method for calculating UWB anchor point coordinates according to an embodiment of the present invention is shown. Figure 6 A method for updating vehicle location based on vehicle movement according to an embodiment of the present invention is shown.

[0040] Reference Figures 3 to 6 The UWB controller 120 of the wireless charging vehicle 100 initiates the wireless charging alignment mode (S110). The wireless charging alignment mode refers to the process of aligning the secondary charging plate 110 of the wireless charging vehicle 100 with the primary charging plate 210 of the wireless charging station 200.

[0041] UWB controller 120 scans the UWB signal transmitted by UWB anchor 221 by utilizing UWB tags 121, 122, 123, 124, 125, 126 and 127 (S120).

[0042] The UWB controller 120 can compare the strength (i.e., Received Signal Strength Indicator (RSSI)) and distance values ​​of the UWB signals received by the various UWB tags 121, 122, 123, 124, 125, 126, and 127, and can determine the location quadrant of the UWB anchor point 221 of the primary charging board 210 (S130). Figure 4As shown, a quadrant is set with reference to the forward direction of the wireless charging vehicle 100, and the position quadrant can be determined as one of the quadrants set with the wireless charging vehicle 100 as the reference.

[0043] Specifically, the UWB controller 120 can compare the UWB signal strength and distance values ​​of the third UWB tag 123 located on the left side of the wireless charging vehicle 100 with the UWB signal strength and distance values ​​of the fourth UWB tag 124 located on the right side of the wireless charging vehicle 100 to determine whether the UWB anchor point 221 is located on the right or left side of the wireless charging vehicle 100. The UWB controller 120 can also compare the UWB signal strength and distance values ​​of one of the first UWB tags 121 and the second UWB tags 122 located at the front of the wireless charging vehicle 100 with the UWB signal strength and distance values ​​of the fifth UWB tag 125 located at the rear of the wireless charging vehicle 100 to determine whether the UWB anchor point 221 is located at the front or rear of the wireless charging vehicle 100. The UWB controller 120 can combine these two results to determine which quadrant the UWB anchor point 221 of the primary charging board 210 is located in.

[0044] UWB controller 120 classifies line-of-sight (LOS) sensor values ​​and non-line-of-sight (NLOS) sensor values ​​based on the determined quadrants (S140). UWB controller 120 can identify UWB tags with LOS values ​​based on the determined quadrants as LOS sensors, and can identify UWB tags without LOS values ​​based on the determined quadrants as NLOS sensors. UWB controller 120 can utilize the LOS sensor values ​​of LOS sensors to reduce errors caused by NLOS sensor values.

[0045] The UWB controller 120 calculates the coordinates of the UWB anchor point 221 using LOS sensor values ​​(S150). The UWB controller 120 can calculate the relative coordinates of the UWB anchor point 221 with respect to the wireless charging vehicle 100. For example, as... Figure 5 As shown, when the UWB anchor point 221 of the primary charging board 210 is located in the first quadrant and the distance values ​​(T1, T2, T3, T4 and T5) of the five UWB tags are measured, the UWB controller 120 can calculate the coordinates (x', y') of the UWB anchor point 221 by using the distance values ​​(T1, T2 and T4) corresponding to the LOS sensor values ​​as shown in Equation 1.

[0046] Equation 1

[0047] T1 2 =(y′+w / 2) 2 +(x'-L / 2) 2

[0048] T2 2 =(y'-w / 2) 2 +(x'-L / 2) 2

[0049] T4 2 =(y'-w / 2) 2 +(x'-(L / 2-Xoffset)) 2

[0050]

[0051]

[0052] Here, L is the vehicle length, w is the vehicle width, and Xoffset is the distance between the horizontal UWB tags. For ease of description, the z-axis coordinate of UWB anchor point 221 is omitted.

[0053] As the coordinates of the UWB anchor 221 are calculated, the wireless charging vehicle 100 can move toward the UWB anchor 221 of the primary charging plate 210 based on the coordinates of the UWB anchor 221.

[0054] The UWB controller 120 can update the vehicle position based on the movement of the wireless charging vehicle 100 (S160). For example... Figure 6 As shown, the UWB controller 120 can update the vehicle position by utilizing odometer information based on vehicle movement. The odometer information can be obtained from wheel speed sensors and yaw rate sensors, and the UWB controller 120 can estimate the vehicle position by utilizing the wheel speed sensor values ​​and yaw rate sensor values. The vehicle position can be updated as shown in Equation 2.

[0055] Equation 2

[0056]

[0057] Here, x and y are the vehicle positions at the previous time (t = k - 1), x' and y' are the vehicle positions at the current time (t = k), ρ is the distance the vehicle has traveled, and θ is the yaw angle.

[0058] The vehicle position estimated using odometer information may contain errors. Therefore, the UWB controller 120 can use LOS sensor values ​​(UWB sensor distance values) to correct for these errors. That is, the UWB controller 120 can update the vehicle position by combining odometer information and LOS sensor values. Because the UWB controller 120 utilizes LOS sensor values ​​with LOS, the accuracy of the distance values ​​can be improved, and the error in the vehicle position can be minimized.

[0059] UWB controller 120 determines whether the charging pad is aligned so that the wireless charging vehicle 100 moves and the primary charging pad 210 faces the secondary charging pad 110 (S170). When the charging pad is not aligned, UWB controller 120 may repeat steps S130 to S160 to align the charging pad.

[0060] When the charging pad is aligned, the UWB controller 120 completes the wireless charging alignment mode, and the wireless charging vehicle 100 can stop and turn off the start (OFF) (S180) and start wireless charging (S190).

[0061] As described above, the wireless charging vehicle 100 can locate the primary charging plate 210 of the wireless charging station 200 from a distance using UWB technology, and the secondary charging plate 110 of the wireless charging vehicle 100 can be accurately aligned with the primary charging plate 210 through the automatic parking and autonomous driving functions of the wireless charging vehicle 100, thereby optimizing wireless charging efficiency.

[0062] The following will refer to Figure 7 This paper describes a wireless charging method for a wireless charging vehicle 100 utilizing a particle filter scheme. (Compared with reference to...) Figures 3 to 6 The differences are described by comparing the features described.

[0063] Figure 7 This is a flowchart illustrating a wireless charging method for a wireless charging vehicle according to another embodiment of the present invention.

[0064] Reference Figure 7 The UWB controller 120 initiates wireless charging alignment mode (S210) and searches for UWB anchor points 221 (S215).

[0065] UWB controller 120 can sample UWB sensor values ​​based on the UWB signal strength and distance values ​​received by each UWB tag 121, 122, 123, 124, 125, 126 and 127 (S220).

[0066] The UWB controller 120 can estimate the location quadrant of the UWB anchor point 221 by utilizing sampled UWB sensor values ​​(S225). The UWB controller 120 can estimate the location quadrant of the UWB anchor point 221 by comparing the UWB sensor values ​​of the various UWB tags 121, 122, 123, 124, 125, 126, and 127 surrounding the wireless charging vehicle 100 on a plane.

[0067] The UWB controller 120 calculates the coordinates of the UWB anchor point 221 relative to the wireless charging vehicle 100 by utilizing the LOS sensor values ​​of the LOS sensors with LOS in the UWB tags 121, 122, 123, 124, 125, 126 and 127 (S230). The coordinates of the UWB anchor point 221 can be calculated as shown in Equation 1.

[0068] As the coordinates of the UWB anchor 221 are calculated, the wireless charging vehicle 100 can move towards the UWB anchor 221 of the primary charging plate 210 based on the coordinates of the UWB anchor 221.

[0069] The UWB controller 120 can estimate and update the position of the wireless charging vehicle 100 by utilizing an extended Kalman filter (EKF) for estimating the position of the nonlinear system and a particle filter scheme for estimating the position of the vehicle.

[0070] In detail, the UWB controller 120 can predict particle positions using odometry information (S235), collect actual measured values ​​of UWB sensor values ​​(LOS sensor values) (S240), and preprocess the UWB sensor values ​​and update the particle weight values ​​(S245). The UWB controller 120 can resample the particles (S250) and update the position of the UWB anchor point 221 by applying the updated particle weight values ​​(S255). The UWB controller 120 can determine whether the charging plate is aligned (S260), and if not, repeat steps S220 to S255 to find the particle with the highest weight value by utilizing an extended Kalman filter.

[0071] When the charging pad is aligned, the UWB controller 120 can complete the wireless charging alignment mode, and the wireless charging vehicle 100 can stop and turn off the start (OFF) (S265) and start wireless charging (S270).

[0072] The accompanying drawings and embodiments of this invention are merely examples illustrating the invention and are not intended to limit the scope of the invention as defined by the appended claims. Therefore, those skilled in the art will understand that various modifications or variations from the embodiments, as well as other equivalent embodiments, are possible. Consequently, the scope of protection of this invention can be defined by the technical solutions in the appended claims.

Claims

1. A wireless charging vehicle, comprising: The secondary charging board generates an induced current through the magnetic field produced by the primary charging board of the wireless charging station, and charges the battery. Multiple ultra-wideband (UWB) tags were set up around the vehicle; as well as The UWB controller executes a wireless charging alignment mode to align the secondary charging pad with the primary charging pad by utilizing sensor values ​​measured by the UWB tag. The UWB controller calculates the coordinates of the primary charging board by utilizing the line-of-sight (LOS) sensor values ​​of the UWB tags that have a line of sight. The UWB controller scans the UWB signals transmitted by the primary charging pad, wireless charger, and UWB anchor points located in the wireless charging station, and the parking lot. The UWB anchor point sends the UWB signal according to the request of the wireless charging vehicle.

2. The vehicle according to claim 1, wherein, The UWB controller is configured as follows: Compare the UWB signals of the UWB tags; Determine the quadrant in which the primary charging board is located; and Based on the location quadrant, UWB tags that have the line of sight and UWB tags that do not have the line of sight are distinguished from the UWB tags.

3. The vehicle according to claim 1, wherein, The UWB controller assembly updates the vehicle's position based on the vehicle's odometer information and LOS sensor values.

4. The vehicle according to claim 3, wherein, The UWB controller updates the vehicle position by utilizing an extended Kalman filter and a particle filter scheme.

5. The vehicle according to claim 1, wherein, The secondary charging plate is located at the bottom of the vehicle.

6. The vehicle according to claim 1, wherein, The plurality of UWB tags are located on the front left, front right, left middle, right middle, middle rear, rear left, and rear right of the vehicle.

7. The vehicle according to claim 1, wherein, The vehicles include electric vehicles, autonomous vehicles, or hybrid vehicles.

8. The vehicle according to claim 1, wherein, The wireless charging station includes the primary charging plate, the wireless charger, and the UWB anchor point.

9. The vehicle according to claim 8, wherein, The wireless charger controls the power supplied to the primary charging pad and provides vehicle charging information to the vehicle's user.

10. A wireless charging method for a wireless charging vehicle, comprising: Scanning UWB signals emitted by primary charging pads, wireless chargers, and UWB anchors located in wireless charging stations and parking lots. Compare the UWB signals received by multiple ultra-wideband tags (UWB tags) and determine the location quadrant of the UWB anchor point; Based on the location quadrant, the coordinates of the UWB anchor point are calculated using the line-of-sight (LOS) sensor values ​​of the UWB tags with a line of sight among the plurality of UWB tags; and Based on the coordinates of the UWB anchor point, move towards the UWB anchor point. The UWB anchor point sends the UWB signal according to the request of the wireless charging vehicle.

11. The method of claim 10, further comprising combining odometer information based on the vehicle's movement and the LOS sensor value to update the vehicle position.

12. The method according to claim 11, wherein, The odometer information is obtained from the wheel speed sensor and the yaw rate sensor.

13. The method according to claim 11, wherein, The vehicle position is updated by utilizing an extended Kalman filter and a particle filter scheme.

14. The method of claim 10, further comprising dividing the LOS sensor values ​​and the non-line-of-sight sensor values, i.e., NLOS sensor values, based on a determined position quadrant.

15. The method of claim 10, wherein the plurality of UWB tags are configured to surround the vehicle.

16. The method of claim 10, further comprising: Ensure the secondary charging board is aligned with the primary charging board for charging; Control the power supplied to the primary charging board; as well as Provide the vehicle's charging information to the vehicle's user.

17. A wireless charging method for a wireless charging vehicle, comprising: Start wireless charging alignment mode; Scanning UWB signals emitted by primary charging pads, wireless chargers, and UWB anchors located in wireless charging stations and parking lots. Search the UWB anchor points; The UWB sensor values ​​are sampled based on the UWB signal strength and distance values ​​received by the UWB tag installed on the vehicle; The location quadrant of the UWB anchor point is estimated based on the comparison of the UWB sensor values. The coordinates of the UWB anchor point relative to the vehicle are calculated by utilizing the line-of-sight sensor value, i.e., the LOS sensor value, of the UWB tag that has LOS in the UWB tag. Predicting particle positions by utilizing odometry information; and Update the position of the UWB anchor point. The UWB anchor point sends the UWB signal according to the request of the wireless charging vehicle.

18. The method of claim 17, further comprising: Based on the updated position of the UWB anchor point, the vehicle moves toward the UWB anchor point; Ensure that the secondary charging plate installed on the vehicle is aligned with the primary charging plate installed on the parking surface; Stop and shut down the vehicle; as well as Initiate wireless charging for the vehicle.

19. The method according to claim 18, wherein, The wireless charging of the vehicle includes: Controlling the power supplied to the primary charging plate; and Provide the vehicle's charging information to the vehicle's user.

20. The method of claim 17, wherein, The vehicles include electric vehicles, autonomous vehicles, or hybrid vehicles.

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