A retractable secondary coil device for inductive charging pavement and its cooperative control method

Abstract

This invention relates to the field of wireless power transmission for vehicles, and in particular to a retractable secondary coil device and its cooperative control method for inductive charging pavement. The device includes a secondary coil assembly for forming magnetic coupling with the primary coil inside the pavement and receiving wireless power; a telescopic mounting mechanism for guiding, constraining, and supporting the vertical movement of the secondary coil assembly; and a drive unit connected to the telescopic mounting mechanism for driving the secondary coil assembly to reciprocate between an extended working position and a retracted safe position. This invention, by extending the secondary coil to the working position during charging, shortens the air gap between the primary and secondary coils, which helps improve the magnetic coupling conditions of the system from a structural perspective. Because the transmission distance between the primary and secondary coils is reduced, the mutual inductance and coupling coefficient of the system are improved during operation, thereby helping to reduce power fluctuations and improve the operational stability and transmission performance of the wireless charging system.

Description

Technical Field

[0001] This invention relates to the field of wireless power transmission for vehicles, and in particular to a retractable secondary coil device for inductive charging pavement and its cooperative control method. Background Technology

[0002] In inductive charging pavement systems, the primary coil is typically embedded within the pavement structure layer, while the secondary coil is installed in the vehicle chassis. Wireless power transmission is achieved through magnetic coupling between the two. Due to factors such as the embedment depth of the primary coil and the vehicle's ground clearance, a significant gap usually exists between the primary and secondary coils. As this gap increases, the mutual inductance and coupling coefficient between the coils decrease significantly, potentially leading to reduced system transmission efficiency.

[0003] Existing technologies mainly improve coupling performance by optimizing coil structure parameters, magnetic material arrangement, or compensation circuit configuration. However, these methods are still limited by the objective constraints of vehicle chassis space and road surface thickness, making it difficult to effectively shorten the actual distance between the primary and secondary coils from a structural perspective. Therefore, a retractable secondary coil device for inductive charging pavement and its collaborative control method are proposed. Summary of the Invention

[0004] In view of the problems mentioned above or in the prior art, the present invention is proposed.

[0005] Therefore, the object of the present invention is to provide a retractable secondary coil device for inductive charging pavement.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: including, Secondary coil assembly, which is used to form magnetic coupling with the primary coil inside the road surface and to receive wireless power; Telescopic mounting mechanism, which is used to guide, constrain and support the vertical movement of the secondary coil assembly; A drive unit, connected to the telescopic mounting mechanism, is used to drive the secondary coil assembly to reciprocate between the extended working position and the retracted safe position; A position and status detection module is used to monitor the extension displacement, working gap height, or execution status of the secondary coil assembly; and, The collaborative control unit is communicatively connected to the drive unit and the position and status detection module, and also to the vehicle controller and the wireless charging control module. It is used to control the extension and retraction of the secondary coil assembly according to the vehicle status, and to perform protective retraction under abnormal operating conditions.

[0007] As a preferred embodiment of the retractable secondary coil device for inductive charging road surface of the present invention, the secondary coil assembly is provided with a protective shell and a sealing structure on the outside to prevent water, dust and road impurities from entering during vehicle operation.

[0008] As a preferred embodiment of the retractable secondary coil device for inductive charging road surface of the present invention, wherein: the retractable installation mechanism includes a guide rail, a bearing bracket is provided on the outside of the guide rail, and a buffer mechanism is installed on the top of the guide rail.

[0009] As a preferred embodiment of the retractable secondary coil device for inductive charging road surface of the present invention, wherein: the secondary coil assembly is mounted on the bearing bracket and moves in the vertical direction under the guidance and constraint of the guide rail; The buffer mechanism provides protection for the secondary coil assembly.

[0010] As a preferred embodiment of the retractable secondary coil device for inductive charging road surface of the present invention, the driving unit may be one of an electric push rod, an electric linear actuator, or a lead screw-slider transmission mechanism.

[0011] As a preferred embodiment of the retractable secondary coil device for inductive charging road surface of the present invention, wherein: the position and state detection module includes at least one of a displacement sensor, a limit switch or an attitude sensor.

[0012] As a preferred embodiment of the retractable secondary coil device for inductive charging road surface of the present invention, wherein: the cooperative control unit is used to control the secondary coil assembly to extend to a preset working position when a vehicle is detected to enter the charging condition, and to control the secondary coil assembly to retract to a safe position when charging ends or the vehicle leaves the charging area.

[0013] The present invention also provides a collaborative control method.

[0014] This invention provides the following technical solution: a cooperative control method, characterized in that it includes any of the retractable secondary coil devices for inductive charging pavements, the method comprising the following steps: S1: Determine whether the vehicle has entered the inductive charging road surface and meets the charging triggering conditions; S2: When the triggering condition is met, control the secondary coil assembly to extend downward to the preset working position, and confirm the position or monitor the process through the position and status detection module. S3: After the secondary coil assembly is in the working position, it forms magnetic coupling with the primary coil inside the road surface and performs wireless power transmission; S4: When charging is finished or the vehicle leaves the charging area, the control drive unit drives the secondary coil assembly to retract to a safe position on the vehicle chassis. S5: When an execution abnormality is detected or the operating status does not meet the safety conditions, control the secondary coil assembly to perform protection retraction.

[0015] As a preferred embodiment of the collaborative control method of the present invention, the charging triggering conditions include valid vehicle location identification, a valid charging request, and vehicle status meeting safety requirements.

[0016] As a preferred embodiment of the collaborative control method of the present invention, the execution abnormality includes at least one of non-position, jamming, or posture abnormality.

[0017] The beneficial effects of the retractable secondary coil device for inductive charging pavement and its cooperative control method of the present invention are as follows: First, the present invention shortens the air gap between the original and secondary coils by extending the secondary coil to the working position under charging conditions, which is beneficial to improving the magnetic coupling conditions of the system from the structural level. Second, as the transmission distance between the primary and secondary coils is reduced, the mutual inductance and coupling coefficient during system operation are improved, which helps to reduce power fluctuations and improve the operational stability and transmission performance of the wireless charging system. Third, by coordinating the extension and retraction of the secondary coil, it is positioned in a position conducive to coupling during charging and retracted to a safe position when not charging. This improves charging performance without affecting vehicle passability and driving safety, and enables adaptive switching of the structure between charging and driving conditions. Fourth, the structure and control method adopted in this invention can be realized through existing electromechanical technology, and can improve the durability of the device in the chassis environment to a certain extent, and has good feasibility in engineering implementation. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 is an overall structural diagram of a retractable secondary coil device for inductive charging road surface proposed in this invention. Figure 2 This is a schematic diagram of the extended working position of a retractable secondary coil device for an inductive charging road surface proposed in this invention. Figure 3This is a schematic diagram of the retractable secondary coil device for inductive charging road surface proposed in this invention, in the safe retraction position. Figure 4 This is a schematic diagram of the control relationship of a collaborative control method proposed in this invention; Figure 5 This is a flowchart illustrating the collaborative control process of the collaborative control method proposed in this invention.

[0020] In the diagram: 1. Secondary coil assembly; 2. Telescopic mounting mechanism; 21. Guide rail; 22. Bearing bracket; 23. Buffer structure; 3. Drive unit; 4. Position and status detection module; 5. Cooperative control unit; 6. Primary coil assembly; 7. Electric vehicle chassis; 8. Charging road surface. Detailed Implementation

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0022] Based on the document content, the following is a reasonable interweaving and expansion of Example 1, retaining the original paragraph structure and highlighting the coordination between structural features, the technical problems solved, and the technical effects achieved in each paragraph: Example 1 Reference Figures 1-3 This is the first embodiment of the present invention. This embodiment provides a retractable secondary coil device for inductive charging road surface. The device is installed in the area below the vehicle chassis and fixed on the structural beam of the vehicle chassis. It includes: secondary coil assembly 1, telescopic mounting mechanism 2, drive unit 3, position and status detection module 4, and cooperative control unit 5.

[0023] Specifically, the secondary coil assembly 1, serving as the vehicle-side wireless power receiving component, is mounted on the support bracket 22 and moves vertically up and down with the telescopic mounting mechanism 2. Through this cooperative structure, the secondary coil assembly 1 can actively extend downwards when charging is required, effectively solving the problem of reduced coupling coefficient and transmission efficiency caused by excessive spacing between the primary and secondary coils in existing technologies. This achieves the effect of shortening the energy transmission distance and improving system efficiency during charging. When the vehicle is in motion, the secondary coil assembly 1 is in a retracted safe position, its overall outline located within the vehicle chassis envelope, ensuring vehicle passability and driving safety. During charging, the secondary coil assembly 1 can be driven to a downwardly extended working position, closer to the primary coil inside the road surface, achieving adaptive switching between charging performance and driving safety.

[0024] The telescopic mounting mechanism 2 is fixedly installed on the vehicle chassis structure to guide and support the vertical movement of the secondary coil assembly 1. Specifically, the telescopic mounting mechanism 2 includes a guide rail 21, a support bracket 22, a travel limiting structure, and a buffer structure 23. The guide rail 21 limits the movement of the secondary coil assembly 1 to the vertical direction only, suppressing possible lateral swaying during telescopic movement and ensuring the stability of the movement posture. The support bracket 22 supports and connects the secondary coil assembly 1, ensuring its structural strength and rigidity during movement. The travel limiting structure 23 limits its maximum extension position and minimum retraction position to prevent overtravel. The buffer structure reduces mechanical impact and lowers vibration and noise when reaching the limit position. Through the coordinated operation of these components, the issues of guiding accuracy, positioning reliability, and impact resistance during telescopic movement are solved, improving the mechanical durability of the device in complex chassis environments.

[0025] The drive unit 3 is mounted on one side of the telescopic mounting mechanism 2 and is connected to the support bracket 22 for transmission, providing driving force for the vertical movement of the secondary coil assembly 1. The drive unit 3 is implemented in the form of an electric push rod, and its output stroke matches the effective stroke of the telescopic mounting mechanism 2. This drive method features controllable stroke, compact structure, and rapid response, meeting the space and reliability requirements of vehicle chassis integration. It can precisely control the extension height and retraction position of the secondary coil assembly 1 according to the instructions of the cooperative control unit 5, providing an execution basis for achieving closed-loop control and abnormal protection.

[0026] The position and status detection module 4 is located near the telescopic installation mechanism 2. It is used to detect the displacement position, working gap height, or execution status of the secondary coil assembly 1 in real time, and sends the detection signal to the collaborative control unit 5 for positioning judgment, process monitoring, and abnormal status identification. Through this feedback mechanism, the system can accurately confirm whether the secondary coil has reached the preset working position, and promptly detect faults such as jamming, incomplete positioning, or abnormal posture. This solves the problem of unknown status during telescopic execution and provides key data support for closed-loop control and safety protection strategies.

[0027] The collaborative control unit 5 is integrated into the vehicle controller. It communicates with the drive unit 3 and the attitude and position detection module 4, as well as with the vehicle control system and the wireless charging control system. It is used to uniformly schedule and control the extension and retraction process of the secondary coil assembly 1. This collaborative control unit can automatically determine whether the charging triggering conditions are met based on vehicle location identification information, charging requests, and vehicle operating status, and prioritizes the implementation of a protective retraction strategy under abnormal operating conditions. Through this intelligent linkage control, the coordination and safety issues of secondary coil state switching under different operating conditions are solved, achieving an optimal balance between charging performance and driving safety.

[0028] Furthermore, the outer side of the secondary coil assembly 1 is provided with a protective shell and sealing structure to provide necessary protection against mud, dust, gravel, and external impacts in the vehicle chassis operating environment. This protective design effectively solves the problems of water, dust, and road impurities in the chassis environment causing contamination, corrosion, or jamming of the coil and moving mechanism, significantly improving the device's environmental adaptability and long-term operational reliability under harsh road conditions.

[0029] In use, when the vehicle is in normal driving condition, the secondary coil assembly 1 is retracted to a safe position within the vehicle chassis envelope by the telescopic mounting mechanism 2 under the drive of the drive unit 3, to ensure the vehicle's passability and driving safety. When the vehicle travels to the inductive charging road area and the cooperative control unit 5 determines that the charging triggering conditions are met based on vehicle position recognition, charging request, and operating status, the cooperative control unit 5 controls the drive unit 3 to start, driving the support bracket 22 to extend the secondary coil assembly 1 vertically downward under the constraint of the guide rail 21, until the signal from the position and status detection module 4 confirms that it has reached the preset working position, and then stops. At this time, the secondary coil assembly 1 is close to the primary coil inside the road surface, forming a stable magnetic coupling for wireless power transmission. When charging ends or the vehicle leaves the charging area, the cooperative control unit 5 controls the drive unit 3 to move in the opposite direction, retracting the secondary coil assembly 1 to a safe position. During the entire process, if the position and status detection module 4 detects abnormalities such as non-positioning, jamming, or abnormal posture, or if the vehicle's operating status does not meet safety conditions, the cooperative control unit 5 will immediately control the drive unit 3 to perform protective retraction, allowing the secondary coil assembly 1 to return to a safe position first. This achieves coordinated control of vehicle driving safety and device self-protection while ensuring charging efficiency.

[0030] In summary, through the cooperation of the drive unit 3 and the telescopic mounting mechanism 2, the secondary coil assembly 1 actively extends downward to a working position close to the primary coil on the road surface during charging. This effectively shortens the air gap between the primary and secondary coils, improves the magnetic coupling conditions at the structural level, and significantly enhances the mutual inductance and coupling coefficient of the system. This helps reduce power fluctuations and improves wireless power transmission efficiency and operational stability. Furthermore, during non-charging conditions, the secondary coil assembly 1 can be retracted to a safe position within the vehicle chassis's envelope. Combined with the protective shell and sealing structure's protection against mud, dust, and external impacts, this solves the problem of traditional fixed coils affecting vehicle passability and driving safety, achieving a balance between charging performance and driving stability. The device features adaptive switching between safety modes; and through the linkage between the position and status detection module 4 and the collaborative control unit 5, it can monitor the extension displacement, positioning status, and execution anomalies in real time. When it detects non-positioning, jamming, or abnormal posture, it automatically executes a protection retraction strategy, effectively avoiding chassis scraping, mechanical damage, and driving risks, significantly improving the safety and reliability of the device in complex chassis environments. At the same time, through the collaborative design of the guide rail 21, the bearing bracket 22, and the stroke limit and buffer structure 23, the device ensures the guiding accuracy, positioning reliability, and impact resistance of the vertical movement of the secondary coil assembly 1. Combined with compact drive forms such as electric push rods, the device has good engineering feasibility and chassis integration adaptability.

[0031] Example 2, refer to Figures 4-5 This is the second embodiment of the present invention. Unlike the previous embodiment, this embodiment provides a cooperative control method for inductive charging.

[0032] Specifically, it includes the following steps: S1: Determine whether the vehicle has entered the inductive charging road surface and meets the charging triggering conditions; S2: When the triggering condition is met, control the secondary coil assembly 1 to extend downward to the preset working position, and confirm the position or monitor the process through the position and status detection module 4. S3: After the secondary coil assembly 1 is in the working position, it forms magnetic coupling with the primary coil inside the road surface and performs wireless power transmission; S4: When charging is finished or the vehicle leaves the charging area, the control drive unit 3 drives the secondary coil assembly 1 to retract to a safe position on the vehicle chassis.

[0033] S5: When an execution abnormality is detected or the operating status does not meet the safety conditions, control the secondary coil assembly 1 to perform protection retraction.

[0034] Charging trigger conditions include valid vehicle location identification, a valid charging request, and the vehicle status meeting safety requirements.

[0035] Execution abnormalities include at least one of the following: incomplete positioning, jamming, or abnormal posture.

[0036] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A retractable secondary coil device for inductive charging pavement, characterized in that: include, Secondary coil assembly (1), which is used to form magnetic coupling with the primary coil inside the road surface and to receive wireless power; Telescopic mounting mechanism (2) is used to guide, constrain, and support the vertical movement of the secondary coil assembly (1); A drive unit (3), which is connected to the telescopic mounting mechanism (2), is used to drive the secondary coil assembly (1) to reciprocate between the extended working position and the retracted safe position; Position and status detection module (4) is used to monitor the extension displacement, working gap height, or execution status of the secondary coil assembly (1); and, The collaborative control unit (5) is connected to the drive unit (3) and the position and status detection module (4) respectively, and is also connected to the vehicle controller and the wireless charging control module. It is used to control the extension and retraction of the secondary coil assembly (1) according to the vehicle status, and to perform protective retraction under abnormal working conditions.

2. The retractable secondary coil device for inductive charging pavement as described in claim 1, characterized in that: The outer side of the secondary coil assembly (1) is provided with a protective shell and a sealing structure to prevent water, dust and road impurities from entering during vehicle operation.

3. The retractable secondary coil device for inductive charging pavement as described in claim 2, characterized in that: The telescopic installation mechanism (2) includes a guide rail (21), a bearing bracket (22) is provided on the outside of the guide rail (21), and a buffer mechanism (23) is installed on the top of the guide rail (21).

4. The retractable secondary coil device for inductive charging pavement as described in claim 3, characterized in that: The secondary coil assembly (1) is mounted on the bearing bracket (22) and moves vertically under the guidance and constraint of the guide rail (21); The buffer mechanism (23) can provide protection for the secondary coil assembly (1).

5. The retractable secondary coil device for inductive charging pavement as described in claim 4, characterized in that: The drive unit (3) can be one of an electric push rod, an electric linear actuator, or a lead screw-slider transmission mechanism.

6. The retractable secondary coil device for inductive charging pavement as described in claim 5, characterized in that: The position and status detection module (4) includes at least one of a displacement sensor, a limit switch, or an attitude sensor.

7. The retractable secondary coil device for inductive charging pavement as described in claim 6, characterized in that: The cooperative control unit (5) is used to control the secondary coil assembly (1) to extend to a preset working position when the vehicle is detected to enter the charging condition, and to control the secondary coil assembly (1) to retract to a safe position when the charging ends or the vehicle leaves the charging area.

8. A cooperative control method, characterized in that, The method comprising the retractable secondary coil device for inductive charging pavement according to any one of claims 1 to 7 includes the following steps: S1: Determine whether the vehicle has entered the inductive charging road surface and meets the charging triggering conditions; S2: When the triggering condition is met, control the secondary coil assembly (1) to extend downward to the preset working position, and confirm the position or monitor the process through the position and status detection module (4); S3: After the secondary coil assembly (1) is in the working position, it forms magnetic coupling with the primary coil inside the road surface and performs wireless power transmission; S4: When charging is finished or the vehicle leaves the charging area, the control drive unit (3) drives the secondary coil assembly (1) to retract to a safe position on the vehicle chassis. S5: When an execution abnormality is detected or the operating state does not meet the safety conditions, control the secondary coil assembly (1) to perform protection retraction.

9. The cooperative control method as described in claim 8, characterized in that: The charging triggering conditions include valid vehicle location identification, a valid charging request, and the vehicle status meeting safety requirements.

10. The cooperative control method as described in claim 9, characterized in that: The execution anomaly includes at least one of the following: incomplete execution, jamming, or abnormal posture.

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