A variable air gap energy recovery device, system and method

Abstract

This invention relates to the field of motor technology and discloses a variable air gap energy recovery device, system, and method. The device includes a housing with a stator disk inside and rotor disks on both sides. Two sets of sliding grooves are provided on the housing. Each rotor disk, on the side away from the stator disk, is rotatably engaged with one end of a shift fork. The other end of the shift fork passes through the sliding groove and extends to the outside of the housing, connecting to an air gap adjustment mechanism. The air gap adjustment mechanism drives the shift fork to slide within the sliding groove, causing the two sets of rotor disks to move closer to or further away from the stator disk. This achieves dynamic air gap adjustment and real-time changes to the parameters of the energy recovery device. During energy conversion, it continuously optimizes energy conversion efficiency and expands the energy conversion range. This invention uses the air gap adjustment mechanism as a mechanical structure to adjust the distance between the rotor disk and the stator disk, achieving dynamic air gap adjustment and improving energy recovery efficiency.

Description

Technical Field

[0001] This invention relates to the field of motor energy recovery technology, and in particular to a variable air gap energy recovery device, system and method. Background Technology

[0002] Axial flux motors are widely used in energy recovery applications due to their high power density and compact structure. The air gap, a crucial component of the magnetic circuit, directly determines the reluctance and inductance characteristics. Increasing the air gap leads to increased reluctance and decreased inductance; conversely, decreasing the air gap reduces reluctance and increases inductance. This characteristic makes the air gap a key factor in adjusting the motor's electromagnetic parameters. In energy recovery (power generation) mode, the generator's power generation characteristics, output voltage stability, and load matching are all closely related to electromagnetic parameters such as inductance.

[0003] In existing technologies, the air gap of axial flux motors is mostly a fixed structure, or can only be adjusted through complex operations when the motor is stopped. There is a lack of mature solutions for real-time dynamic adjustment of the air gap during operation. A fixed air gap prevents the motor's electromagnetic parameters from flexibly adjusting to load fluctuations, speed changes, and other operating conditions, resulting in a narrow energy recovery efficiency range. For example, during the braking process of an electric vehicle, as the vehicle speed changes from high to low, the motor is prone to leaving its high-efficiency range, leading to low energy recovery efficiency at low or high speeds. In wind power generation scenarios, it cannot adapt to the variable wind speeds, making it difficult to start power generation in light winds and increasing the risk of efficiency degradation in strong winds.

[0004] Furthermore, the non-dynamic adjustment of the air gap may also cause problems such as vibration, increased noise, and accelerated device losses due to electromagnetic parameter mismatch, affecting the operational reliability and service life of the energy recovery system. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a variable air gap energy recovery device, system, and method. By adjusting the distance between the rotor disk and the stator disk through an air gap adjustment mechanism, the air gap can be dynamically adjusted, thereby optimizing the electromagnetic parameters of the motor, widening the high-efficiency range of energy recovery, and improving recovery efficiency and system adaptability.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0007] In a first aspect, a variable air gap energy recovery device includes an outer casing, a stator disk inside the outer casing, and rotor disks on both sides of the stator disk. The outer casing has two sets of sliding grooves, and the side of each rotor disk away from the stator disk is rotatably engaged with one end of a shift fork. The other end of the shift fork passes through the sliding groove and extends to the outside of the outer casing to connect with an air gap adjustment mechanism. The air gap adjustment mechanism drives the shift fork to slide in the sliding groove, causing the two sets of rotor disks to move closer to or away from the stator disk, thereby realizing dynamic air gap adjustment and real-time changes to the parameters of the energy recovery device. During the energy conversion process, the energy conversion efficiency is continuously optimized, and the energy conversion range is broadened.

[0008] As a further implementation, the outer casing is provided with a drive shaft along the axial direction, the stator disk and the rotor disk are located around the drive shaft, a drive block is provided in the middle of the drive shaft, a connecting shaft is provided laterally on the drive block, the end of the connecting shaft passes through the rotor disk, so that the drive shaft and the rotor disk rotate synchronously, and the rotor disk and the connecting shaft slide together; the drive block is located on the inner side of the stator disk and is arranged coaxially with the stator disk, the middle position of the connecting shaft passes through the drive block and is arranged circumferentially on the drive block, and the connecting shaft is arranged parallel to the drive shaft.

[0009] As a further implementation, a fixing block is provided at the center of the rotor disk away from the stator disk. The fixing block has an annular groove, and the shift fork rotates with the annular groove. A first bearing is provided between the fixing block and the transmission shaft, and the connecting shaft passes through the fixing block.

[0010] As a further implementation, the outer casing is provided with end caps at both ends, the drive shaft extends out of the end caps at both ends, and a second bearing is provided between the end caps and the drive shaft.

[0011] As a further implementation, the air gap adjustment mechanism includes a displacement slider fixing frame, which is hollow and has a sliding cavity at the top. The sliding cavity is connected to the hollow position. The displacement slider fixing frame is also equipped with a driving component, and a lead screw is provided at the output end of the driving component, which extends to the sliding cavity.

[0012] As a further implementation, the two sets of shift forks extend from one end of the outer shell and are connected to displacement sliders. The displacement sliders slide in conjunction with the sliding cavity. The side of the two sets of displacement sliders that are close to each other is an inclined surface, and a dovetail groove is provided on the inclined surface.

[0013] As a further implementation, the lead screw is threadedly engaged with the wedge block to enable the wedge block to move up and down in the hollow position and sliding cavity of the displacement slider fixing frame. The two sides of the wedge block are parallel to the inclined surface of the displacement slider, and a dovetail block is provided, which engages with the dovetail groove.

[0014] As a further implementation, a third bearing is provided between the shift fork and the annular groove.

[0015] Secondly, an energy recovery system includes an energy recovery device as described above, and further includes a controller, a speed sensor, and a load detection module. The speed sensor is located at the drive shaft to detect the speed, the load detection module is used to detect the status parameters of the energy recovery device, and the controller is connected to the load detection module, the speed sensor, and the drive component of the air gap adjustment mechanism.

[0016] Thirdly, an energy recovery method, employing the energy recovery system described above, includes the following steps:

[0017] The rotor disk inside the energy recovery device rotates relative to the stator disk, the drive shaft rotates synchronously with the rotor disk, the speed sensor detects the speed of the drive shaft in real time, and the load detection module collects the status parameters of the energy recovery device in real time.

[0018] The controller acquires the transmission shaft speed and status parameters, and controls the drive components of the air gap adjustment mechanism to work according to the speed signal and the corresponding status parameters. The rotor disk moves closer to or further away from the stator disk through the shift fork, and the air gap is dynamically adjusted in real time.

[0019] The beneficial effects of the present invention are as follows:

[0020] 1. The energy recovery device of the present invention, by setting a sliding groove on the outer shell, utilizes a fork to rotate with the rotor disk at one end, and the other end to pass through the sliding groove and extend out of the outer shell to connect with the air gap adjustment mechanism. The distance between the rotor disk and the stator disk is adjusted through this mechanical structure of the air gap adjustment mechanism, thereby achieving the purpose of dynamically adjusting the air gap. By using the air gap as a controllable parameter, the electromagnetic parameters are actively optimized, the high-efficiency range of energy recovery is widened, and the problem of low efficiency of fixed air gap motors when the speed and load change is solved, thus improving the energy recovery efficiency.

[0021] 2. Based on the transmission shaft speed detected by the speed sensor, the performance of the motor under different operating conditions is dynamically optimized. That is, by dynamically controlling the air gap, the power generation output parameters of the motor are optimized to ensure that the energy recovery device always works in the high-efficiency range. When applied to new energy vehicles, mechanical energy can be converted into electrical energy to charge the battery and improve the driving range when the accelerator is released.

[0022] 3. In electric vehicle braking scenarios, the air gap can be dynamically adjusted according to vehicle speed to achieve efficient energy recovery across the entire vehicle speed range and improve vehicle range; in wind power generation scenarios, the cut-in wind speed can be reduced to achieve power generation in light winds, while adapting to wind speed fluctuations to maximize wind energy capture and improve system adaptability and reliability.

[0023] 4. The air gap adjustment mechanism adopts a combination structure of geared motor, lead screw, wedge block, displacement slider fixing frame and displacement slider, which accurately converts the rotational motion of the lead screw into the axial displacement of the rotor disk. It has high adjustment accuracy and fast response speed. Combined with dual closed-loop control and multi-parameter collaborative optimization strategy, it realizes precise control of the air gap and ensures stable operation of the system.

[0024] 5. The energy recovery device of the present invention adopts a dual rotor disk single stator disk (RSR) structure, which eliminates the problem of unilateral magnetic pull. The stator disk adopts a non-magnetic support structure and a slotless tooth design to eliminate stator iron loss and hysteresis. Combined with the NS magnetic circuit design, it significantly improves the motor power density and energy recovery efficiency, and reduces operating noise. Attached Figure Description

[0025] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0026] Figure 1 This is a cross-sectional view of the variable air gap energy recovery device in an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the transmission shaft in an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the rotor disk structure in an embodiment of the present invention;

[0029] Figure 4 This is a partial structural diagram of the rotor disk and shift fork in an embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the air gap adjustment mechanism in an embodiment of the present invention;

[0031] Figure 6 This is a schematic diagram of the structure of the displacement slider fixing frame in an embodiment of the present invention;

[0032] Figure 7 This is a schematic diagram of the wedge block structure in an embodiment of the present invention;

[0033] Figure 8 This is a schematic diagram of the connection between the fork and the displacement slider in an embodiment of the present invention;

[0034] Figure 9 This is a schematic diagram of the rotor structure in an embodiment of the present invention;

[0035] Figure 10 This is a schematic diagram of the arrangement structure of the coils on the stator disk in an embodiment of the present invention;

[0036] Figure 11This is a schematic diagram of the arrangement structure of permanent magnets on the rotor disk in an embodiment of the present invention;

[0037] Figure 12 This is a schematic diagram of the relationship between magnetic induction intensity and air gap in an embodiment of the present invention;

[0038] Figure 13 This is a schematic diagram comparing the arrangement of permanent magnets in different directions.

[0039] The diagram exaggerates the spacing or dimensions between parts to show their positions; the diagram is for illustrative purposes only.

[0040] The components are: 1. Stator disk, 2. Rotor disk, 3. Permanent magnet, 4. Outer shell, 5. End cover, 6. Second bearing, 7. Drive shaft, 8. First bearing, 9. Connecting shaft, 10. Shift fork, 11. Displacement slider, 12. Displacement slider fixing bracket, 13. Gear motor, 14. Lead screw, 15. Wedge block, 16. Coil, 21. Fixing block, 22. Annular groove, 23. Second through hole, 41. Slide groove, 71. Drive block, 711. First through hole, 101. Shift fork rod, 102. Arc fastener, 111. Transverse slider, 112. Dovetail groove, 121. Sliding cavity, 122. Sliding groove, 151. Dovetail block. Detailed Implementation

[0041] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0042] Example 1

[0043] In a typical embodiment of the present invention, reference is made to Figures 1-13 As shown, a variable air gap energy recovery device includes a housing 4, inside which are a stator disk 1 and a rotor disk 2. The stator disk 1 is fixed inside the housing 4, and the rotor disk 2 can rotate relative to the stator disk 1. A drive shaft 7 is axially mounted on the housing 4. The stator disk 1 and rotor disk 2 are located around the drive shaft 7, with the two rotor disks 2 positioned on either side of the stator disk 1. The stator disk 1 and the rotor disks 2 on either side form an "RSR" structure. The stator disk 1 employs a non-magnetic support structure and a slotless tooth design. A drive block 71 is located in the middle of the drive shaft 7, and a connecting shaft 9 is transversely mounted on the drive block 71. The end of the connecting shaft 9 passes through the rotor disk 2, allowing the drive shaft 7 and rotor disk 2 to rotate synchronously. The rotor disk 2 is slidably fitted with the connecting shaft 9. The rotor disk 2, drive shaft 7, and connecting shaft 9 are connected to form a rotor. Figure 9 As shown, the rotor can rotate as a whole relative to the stator disk 1.

[0044] like Figure 1As shown, the outer casing 4 is provided with two sets of sliding grooves 41. Each rotor disk 2 is rotatably engaged with one end of the shift fork 10 on the side away from the stator disk 1. The other end of the shift fork 10 passes through the sliding groove 41 and extends to the outside of the outer casing 4 to connect with the air gap adjustment mechanism. The air gap adjustment mechanism drives the shift fork 10 to slide in the sliding groove 41. The shift fork 10 drives the two sets of rotor disks 2 to move closer to or away from the stator disk 1, thereby realizing dynamic air gap adjustment.

[0045] like Figure 1 As shown, the outer casing 4 is a cylindrical structure with openings at both the left and right ends. End caps 5 are connected to the openings. A stator disk 1 is fixed in the middle of the inner part of the outer casing 4, and two rotor disks 2 are located on the left and right sides of the stator disk 1.

[0046] The drive shaft 7 is coaxially arranged with the outer casing 4, and its two ends extend through the center of the end cover 5 to the outside of the outer casing 4. A second bearing 6 is provided between the end cover 5 and the drive shaft 7 to ensure that the drive shaft 7 can rotate smoothly.

[0047] Understandably, permanent magnets 3 are arranged on the side of rotor disk 2 closest to stator disk 1, and coils 16 are arranged on stator disk 1, such as... Figure 10 and Figure 11 As shown. The coil 16 winding on the stator disk 1 is mounted on a non-magnetic or insulating material support structure with a slotless design. The magnetic circuit of the permanent magnet 3 on the rotor disk 2 adopts an NS magnetic circuit structure, which can enhance the magnetic field strength and increase the power density of the motor. When the rotor disk 2 rotates, the magnetic field of the permanent magnet 3 rotates, cutting the coil 16 on the stator disk 1, generating a strong induced alternating current in the coil 16. After rectification and voltage regulation, the generated induced alternating current is converted into direct current, which can charge the high-voltage battery pack.

[0048] like Figure 13 The diagram shows a comparison of permanent magnet 3 arrangements in different directions. Both the left and right diagrams show an "RSR" structure. However, in the left diagram, the opposing sides of the permanent magnets 3 on the two rotor disks 2 have the same polarity, while in the right diagram, the opposing sides of the permanent magnets 3 on the two rotor disks 2 have opposite polarities. This embodiment uses the arrangement shown in the right diagram. Compared to the left diagram, this arrangement eliminates the need for the stator disk 1's yoke magnetic circuit and avoids stator yoke iron loss, thus reducing iron loss.

[0049] When the energy recovery device is applied to a generator scenario, when the rotor disk 2 and the stator disk 1 rotate relative to each other, the coil 16 of the stator disk 1 cuts the magnetic field lines of the permanent magnet 3, inducing an alternating electromotive force in the coil 16. An induced current is generated in the closed circuit, thereby converting the mechanical energy of the rotor disk 2 rotation into electrical energy.

[0050] When applied to electric motors, when the rotor disk 2 and stator disk 1 rotate relative to each other, if current is supplied to the coil 16 of the stator disk 1 beforehand, the coil 16 will generate a magnetic field and interact with the magnetic field of the permanent magnet 3 of the rotor disk 2, thereby generating electromagnetic torque, driving the rotor to rotate continuously, and realizing the conversion of electrical energy into mechanical energy.

[0051] like Figure 2 and Figure 3 As shown, a transmission block 71 is provided at the middle position of the transmission shaft 7. The transmission block 71 has a cylindrical block structure and four first through holes 711 are provided along the axial direction. The first through holes 711 are evenly arranged in the circumferential direction on the transmission block 71.

[0052] The stator plate 1 has a circular opening at its center. Figure 1 In the configuration, the transmission block 71 is located at the inner circular opening of the stator disk 1, and the rotation of the transmission block 71 does not interfere with the stator disk 1. The transmission shaft 7 is coaxially arranged with the stator disk 1 and the rotor disk 2, and the connecting shaft 9 passes through the transmission block 71 at the middle position and is arranged circumferentially on the transmission block 71.

[0053] Specifically, four connecting shafts 9 pass through each of the first through holes 711, with the middle position of the connecting shaft 9 corresponding to the position of the first through hole 711. The four connecting shafts 9 are arranged parallel to the transmission shaft 7. Preferably, the connecting shafts 9 and the transmission block 71 are fixedly connected.

[0054] like Figure 3 and Figure 4 As shown, a fixing block 21 is provided at the center of the rotor disk 2 on the side away from the stator disk 1. The fixing block 21 has a hollow channel that communicates with the circular opening at the center of the rotor disk 2 so that the drive shaft 7 can pass through the rotor disk 2.

[0055] The fixed block 21 has a circular cross-sectional shape. The fixed block 21 has an annular groove 22 around its periphery. The fixed block 21 has a second through hole 23 along its circumferential direction. The second through hole 23 is correspondingly provided with the first through hole 711 and the connecting shaft 9, so that both ends of the connecting shaft 9 can pass through the second through hole 23. With the support of the connecting shaft 9, the rotor disk 2 slides on the connecting shaft 9 through the second through hole 23.

[0056] A first bearing 8 is provided between the fixed block 21 and the transmission shaft 7. The first bearing 8 is a sliding bearing to ensure that the rotor disk 2 can slide smoothly along the axial direction.

[0057] It is understandable that when the drive shaft 7 rotates, it can drive the fixed block 21 to rotate through the drive block 71 and the connecting shaft 9, thereby realizing the rotation of the rotor disk 2. Therefore, the rotor disk 2 rotates synchronously with the drive shaft 7.

[0058] like Figure 1 and Figure 4 , Figure 5 As shown, the shift fork 10 includes a shift fork rod 101 and an arc-shaped fastener 102. The shift fork rod 101 is located inside the outer shell 4, and one end is an arc-shaped rod. The arc-shaped rod and the arc-shaped fastener 102 are fixed to the annular groove 22 by a fastener to achieve rotational engagement with the annular groove 22. The end of the shift fork rod 101 located outside the outer shell 4 is fixedly connected to the displacement slider 11. A third bearing is provided between the shift fork 10 and the annular groove 22 so that the rotation of the rotor disk 2 is not interfered with by the shift fork 10. When the rotor disk 2 rotates, the shift fork 10 remains stationary.

[0059] like Figure 1 As shown, the outer casing 4 is provided with two sets of sliding grooves 41, allowing the other end of the shift fork 10 to extend out of the outer casing 4 and connect to the air gap adjustment mechanism. The sliding grooves 41 are located in... Figure 1 The horizontal extension allows the two sets of shift forks 10 to slide laterally within the slide groove 41. The two sets of shift forks 10 can move closer to or further away from each other, thereby driving the two rotor discs 2 closer to or further away from the stator disc 1, thus achieving the adjustment of the distance between the rotor disc 2 and the stator disc 1 and achieving the purpose of air gap adjustment.

[0060] like Figure 1 , Figure 5 and Figure 6 As shown, the air gap adjustment mechanism includes a displacement slider 11, a displacement slider fixing frame 12, a driving component, and a wedge block 15. Specifically, the displacement slider fixing frame 12 is hollow, and a sliding cavity 121 is provided laterally at the top. The sliding cavity 121 is connected to the hollow position of the displacement slider fixing frame 12.

[0061] exist Figure 1 From a certain perspective, the top of the displacement slider fixing bracket 12 on both sides of the sliding cavity 121 is provided with a horizontal sliding groove 122, and the bottom of the displacement slider fixing bracket 12 is provided with a driving component, which is a geared motor 13. Figure 5 As shown, the output end of the geared motor 13 is connected to the lead screw 14. The lead screw 14 passes through the bottom of the displacement slider fixing frame 12, extends through the hollow position to the sliding cavity 121, and is threadedly engaged with the wedge block 15.

[0062] like Figure 7 As shown, the wedge block 15 has an isosceles trapezoidal cross-section, with dovetail blocks 151 on both sides. The two ends of the dovetail blocks 151 are flush with the top and bottom surfaces of the wedge block 15. A threaded hole is vertically provided at the center of the wedge block 15, which engages with the lead screw 14.

[0063] like Figure 5 As shown, the geared motor 13 drives the lead screw 14 to rotate, and the wedge block 15 can rise and fall in the hollow position of the displacement slider fixing frame 12 and the sliding cavity 121. Therefore, the thickness of the wedge block 15 is adapted to the width of the sliding cavity 121.

[0064] like Figure 8As shown, the two sets of forks 10 extend out of the outer shell 4 and are connected to the displacement slider 11. The displacement slider 11 is slidably engaged with the sliding cavity 121. The displacement slider 11 has a set height, with its top end located at the sliding cavity 121 and its bottom end located in the hollow position.

[0065] The two sets of displacement sliders 11 are close to each other on one side of the inclined surface, and dovetail grooves 112 are provided on the inclined surface. The inclined surface of the displacement slider 11 and the inclined surfaces on the left and right sides of the wedge block 15 have the same slope. Therefore, the inclined surfaces on both sides of the wedge block 15 are parallel to the inclined surface of the displacement slider 11, and the dovetail block 151 is engaged with the dovetail groove 112.

[0066] The displacement slider 11 has a horizontal slider 111 at the top of the front and rear sides, which cooperates with the sliding groove 122.

[0067] With the air gap adjustment mechanism described above, when the reduction motor 13 controls the lead screw 14 to rotate, the wedge block 15 can be raised and lowered in the sliding cavity 121 and the hollow position of the displacement slider fixing frame 12. Since the dovetail block 151 cooperates with the dovetail groove 112, the two sets of displacement sliders 11 can move closer or further away from each other, and then drive the two rotor disks 2 to slide laterally through the shift fork 10, changing the distance between the rotor disk 2 and the stator disk 1, so as to achieve the purpose of dynamically adjusting the air gap.

[0068] The energy recovery device in this embodiment uses a sliding groove 41 on the outer shell 4. One end of the fork 10 rotates with the rotor disk 2, and the other end passes through the sliding groove 41 and extends out of the outer shell 4 to connect with the air gap adjustment mechanism. The air gap adjustment mechanism is a mechanical structure that allows for the adjustment of the distance between the rotor disk 2 and the stator disk 1, thereby achieving the purpose of dynamically adjusting the air gap.

[0069] When a speed sensor is installed at one end of the drive shaft 7 of the energy recovery device, the controller connects the speed sensor and the geared motor 13. The controller calculates the speed of the drive shaft detected by the speed sensor and controls the geared motor 13 to operate, thereby adjusting the air gap in real time, which can ensure that the energy recovery device always works in the high-efficiency zone.

[0070] It is understood that the structural arrangement of the speed sensor for detecting speed is existing technology. The structure of this embodiment is equally applicable in the field of electric motors.

[0071] Example 2

[0072] like Figures 1-8As shown, an energy recovery system includes the energy recovery device of Embodiment 1, and further includes a controller, a speed sensor, and a load detection module. The controller is an algorithm controller. The speed sensor is located at the drive shaft 7 to detect the rotational speed of the drive shaft 7. The load detection module is used to detect the state parameters of the energy recovery device, including state of charge (SOC), voltage, and current. The controller is connected to the load detection module, the speed sensor, and the geared motor 13 of the air gap adjustment mechanism.

[0073] The controller can acquire the speed signal of the drive shaft 7 detected by the speed sensor, calculate the optimal air gap based on the speed signal and the corresponding working scenario, and then control the action of the geared motor 13 to dynamically adjust the air gap and ensure the working efficiency of the energy recovery device.

[0074] Understandably, the controller incorporates a maximum power point tracking (MPPT) algorithm and an optimal air gap calculation model. Based on the speed signal and state parameters, it calculates the optimal air gap value and then controls the geared motor 13 to adjust the appropriate air gap. The energy recovery system employs a dual closed-loop control strategy: the outer loop is the energy recovery power or voltage loop, and the inner loop is the air gap position loop. Simultaneously, it combines air gap adjustment with PWM control of power electronic devices to achieve coordinated optimization.

[0075] Example 3

[0076] An energy recovery method, employing the energy recovery system as described in Example 1, includes the following steps:

[0077] The rotor disk 2 in the energy recovery device rotates relative to the stator disk 1, and the drive shaft 7 rotates synchronously with the rotor disk 2. The speed sensor detects the speed of the drive shaft 7 in real time, and the load detection module collects the status parameters of the energy recovery device in real time.

[0078] The controller acquires the rotational speed and status parameters of the drive shaft 7. Based on the speed signal and corresponding status parameters, it controls the geared motor 13 of the air gap adjustment mechanism to operate. This, via the shift fork 10, moves the rotor disk 2 closer to or further away from the stator disk 1, dynamically adjusting the air gap in real time. Specifically, the controller calculates the optimal air gap value under the current operating conditions based on a preset optimal air gap calculation model and a maximum power point tracking algorithm, combined with the current speed signal and status parameters. It then controls the geared motor 13 to adjust the air gap to the optimal value. During energy recovery, the controller continuously monitors changes in rotational speed and load status parameters, dynamically adjusting the air gap size to ensure the motor always operates within the high-efficiency energy recovery range.

[0079] The energy recovery method in this embodiment is applicable to the braking energy recovery scenario of electric vehicles. When the driver presses the brake pedal, the system starts the energy recovery mode, and the controller calculates the optimal air gap value based on the received signal.

[0080] During high-speed braking, the controller controls the air gap adjustment mechanism to reduce the air gap, increase the magnetic induction intensity, and suppress excessive speed, thereby reducing the vehicle's speed and converting kinetic energy into electrical energy, thus achieving energy recovery.

[0081] During the low-to-medium speed braking phase, the controller controls the air gap adjustment mechanism to gradually reduce the air gap, ensuring sufficient induced current is generated at low speeds and improving the recovery power in the low-speed zone.

[0082] When a new energy vehicle is in motion, after the accelerator pedal is released, the rotor disk 2 in the energy recovery device rotates relative to the stator disk 1, and the drive shaft 7 rotates synchronously with the rotor disk 2. The speed of the drive shaft 7 decreases from high to low. The controller calculates by acquiring the speed signal of the drive shaft 7 and the state parameters of the load, and controls the geared motor 13 to adjust the air gap in real time.

[0083] This embodiment can dynamically optimize the performance of the motor under different operating conditions. That is, by dynamically controlling the air gap, the power generation output parameters of the motor can be optimized to achieve efficient energy recovery. When applied to new energy vehicles, mechanical energy can be converted into electrical energy to charge the battery and improve the driving range when the foot is released from the accelerator.

[0084] In energy recovery (power generation) mode, the energy recovery device can function as a generator. Its power generation characteristics, output voltage, and matching degree with the load are all closely related to the electromagnetic parameters of the generator (such as inductance). By changing the air gap, the generator's internal electromagnetic parameters are actually adjusted in real time. By changing the generator's output characteristics, it can be better matched with the charging curve of the downstream energy storage device (such as a battery or supercapacitor), thereby improving the recovery efficiency.

[0085] Understandably, the current regenerative braking process in electric vehicles is more like a powerful power generation mode that "starts regeneration as soon as the accelerator pedal is released." When the accelerator pedal is released, the vehicle will prioritize using its inertia to drive the motor to generate electricity, thereby charging the battery; and this power generation process itself will generate resistance on the wheels, achieving deceleration.

[0086] Traditional mechanical brakes only intervene when greater braking force is required and the brake pedal is pressed deeply. In this traditional energy recovery system, the driver is in a passive state and cannot subjectively control the energy recovery process. However, this embodiment can actively change the air gap to achieve energy recovery, thereby improving recovery efficiency.

[0087] For motors with a fixed air gap, the efficient energy recovery zone is a relatively narrow speed range. During braking, the vehicle speed (corresponding to the drive shaft speed) changes from high to low, passing through the motor's efficient zone, resulting in low recovery efficiency at low or high speeds. This embodiment can dynamically adjust the air gap to ensure that the motor always operates near its highest efficiency point throughout the entire braking process from high to low speed, thereby recovering more energy.

[0088] Throughout the braking and deceleration process, the vehicle speed continuously decreases (i.e., the motor speed continuously decreases). The controller dynamically controls the geared motor 13 in real time, fine-tuning the air gap to keep the power generation system within its peak efficiency range. It can still generate sufficiently strong induced current and braking force at low speeds, ensuring considerable regenerative power at low speeds.

[0089] For daily driving of electric vehicles, at low speeds and high torque, the air gap can be reduced to enhance the magnetic field, thereby enabling the output of greater torque to meet the needs of vehicle starting and climbing. During high-speed cruising, the air gap can be increased to weaken the magnetic field, reducing iron losses and permanent magnet eddy current losses, while also reducing back electromotive force. This allows the motor speed to be further increased without requiring a very high magnetic field weakening current, which can greatly widen the high-efficiency range of the motor, which is crucial for improving the driving range of electric vehicles.

[0090] The curve of magnetic induction intensity as a function of air gap is shown below. Figure 12 As shown, the change in air gap is inversely proportional to the change in magnetic induction intensity. A smaller air gap results in a stronger magnetic field and lower magnetic reluctance, while a larger air gap results in a weaker magnetic field and higher magnetic reluctance. The relationship between the change in air gap and the change in magnetic induction intensity is based on existing technology.

[0091] The energy recovery method of this embodiment is also applicable to wind power generation scenarios, specifically including: in the light wind start-up stage, the controller can obtain the wind speed detected by the wind speed sensor. When the wind speed is low and the wind turbine speed is lower than the start-up threshold, the controller controls the air gap adjustment mechanism to adjust the air gap to the maximum state, reducing the magnetic field strength and start-up torque, so that the wind turbine can start generating electricity under light wind conditions where traditional wind turbines cannot start.

[0092] During the wind speed change adjustment phase, the controller continuously monitors the rotor speed and output power, and dynamically adjusts the air gap according to the maximum power point tracking algorithm: when the wind speed increases, the air gap is appropriately reduced to avoid the risk of overspeed and optimize the conversion efficiency; when the wind speed decreases, the air gap is increased to maintain a high power generation efficiency.

[0093] When the wind speed suddenly increases beyond a certain set value, the controller will slightly increase the air gap. This prevents runaway; increasing the air gap weakens the magnetic field, reduces the torque load on the generator, allows the wind turbine speed to increase appropriately, and captures the suddenly increased wind energy more efficiently, while avoiding the risk of overspeed. At higher wind turbine speeds, a smaller air gap may lead to increased iron loss and heat generation; appropriately increasing the air gap allows the motor to operate in a more efficient range.

[0094] By dynamically adjusting the air gap, the generator's "high-efficiency zone" is widened, and it can actively "track" changing wind speeds to ensure peak efficiency across a wide range from light to strong winds, thereby maximizing wind energy capture.

[0095] Understandably, energy recovery devices can also be used in other fields. The core idea is to guide the dynamic adjustment of the air gap based on the acquired rotational speed signal, thereby improving power generation efficiency.

[0096] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An energy recovery system, characterized in that, The device includes a variable air gap energy recovery unit, which comprises a housing with a stator disk inside and rotor disks on both sides of the stator disk. The housing has two sets of sliding grooves. Each rotor disk, on the side furthest from the stator disk, is rotatably engaged with one end of a shift fork. The other end of the shift fork passes through the sliding groove and extends to the outside of the housing, connecting to an air gap adjustment mechanism. The air gap adjustment mechanism drives the shift fork to slide within the sliding groove, causing the two sets of rotor disks to move closer to or further away from the stator disk. This achieves dynamic air gap adjustment, real-time changes to the parameters of the energy recovery unit, and continuous optimization of energy conversion efficiency and expansion of the energy conversion range during the energy conversion process. It also includes a controller, a speed sensor and a load detection module. The speed sensor is located at the drive shaft to detect the speed. The load detection module is used to detect the status parameters of the energy recovery device. The controller is connected to the load detection module, the speed sensor and the drive component of the air gap adjustment mechanism. The outer casing has a drive shaft along its axial direction. A stator disk and a rotor disk are located around the drive shaft. A drive block is located in the middle of the drive shaft, and a connecting shaft is transversely mounted on the drive block. The end of the connecting shaft passes through the rotor disk, allowing the drive shaft and rotor disk to rotate synchronously. The rotor disk and connecting shaft are in sliding engagement. The drive block is located inside the stator disk and is coaxially arranged with it. The connecting shaft passes through the drive block in its middle position and is arranged circumferentially on the drive block. The connecting shaft is parallel to the drive shaft. A fixing block is located at the center of the rotor disk on the side furthest from the stator disk. The fixing block has an annular groove, and a fork rotates with the annular groove. A first bearing is located between the fixing block and the drive shaft, and the connecting shaft passes through the fixing block. End caps are located at both ends of the outer casing, with the drive shaft extending beyond the end caps. A second bearing is located between the end caps and the drive shaft. The air gap adjustment mechanism includes a displacement slider fixing frame. The displacement slider fixing frame is hollow, with a sliding cavity at the top. The sliding cavity communicates with the hollow position. A driving component is also located on the displacement slider fixing frame, and a lead screw is located at the output end of the driving component, extending to the sliding cavity. The two sets of forks extend from one end of the outer shell and are connected to the displacement slider. The displacement slider slides into the sliding cavity. The side of the two sets of displacement sliders that are close to each other is an inclined surface, and a dovetail groove is provided on the inclined surface. The lead screw is threaded into the wedge block to realize the lifting and lowering of the wedge block in the hollow position of the displacement slider fixing frame and the sliding cavity. The two sides of the wedge block are parallel to the inclined surface of the displacement slider and are provided with dovetail blocks, which are engaged with the dovetail groove.

2. The energy recovery system according to claim 1, characterized in that, A third bearing is provided between the shift fork and the annular groove.

3. An energy recovery method, characterized in that, The energy recovery system as described in claim 1 includes the following steps: The rotor disk inside the energy recovery device rotates relative to the stator disk, the drive shaft rotates synchronously with the rotor disk, the speed sensor detects the speed of the drive shaft in real time, and the load detection module collects the status parameters of the energy recovery device in real time. The controller acquires the transmission shaft speed and status parameters, and controls the drive components of the air gap adjustment mechanism to work according to the speed signal and the corresponding status parameters. The rotor disk moves closer to or further away from the stator disk through the shift fork, and the air gap is dynamically adjusted in real time.

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