A wireless electromagnetic drive electromagnetic automatic centering device and method

Abstract

The present invention discloses a wireless electromagnetic drive electromagnetic automatic centering device and method, which relates to the field of wireless electromagnetic drive. The device includes: a primary side support structure, a primary side control box, primary and secondary side coils, a secondary side control box, a wheel hub motor, a wheel support suspension, and a wheel; the primary side support structure includes a support bottom plate, a slide rail provided on the support bottom plate, two spring support members, two tension springs, and a slider slidably connected to the slide rail; the support bottom plate is fixedly connected to the vehicle body; one end of each of the two spring support members is connected to the support bottom plate, and the other ends are respectively connected to one end of the two tension springs, and the other ends are respectively connected to two side edges of the primary side control box; the primary side control box is connected to the primary side coil, and the primary side controller in the primary side control box is used to calculate the direct current corresponding to the compensation electromagnetic force for offsetting the relative movement between the coils, and obtain the switch state signal in combination with the motor power requirement, so as to control the operation of the primary and secondary side power electronic devices and realize the real-time centering of the primary and secondary side coils.

Description

Technical Field

[0001] The present invention relates to the field of wireless electromagnetic drive, and particularly to an automatic centering device and method for a wireless electromagnetic drive system based on electromagnetic force. Background Art

[0002] In 2010, a technical solution of wireless in-wheel motor (W-IWM) drive was proposed through collaborative research in multiple fields and industries by Bridgestone Corporation, one of the world's top three tire manufacturers, the University of Tokyo, NSK Ltd., Rohm Co., Ltd., and Toyo Electric Mfg. Co., Ltd. This system adopted electromagnetic drive technology and utilized the principle of magnetic resonance coupling to achieve wireless in-wheel motor drive and conduct tests on a wireless in-wheel motor system, realizing a wireless electromagnetic drive solution with a transmission efficiency of 89% and a transmission power of 3.3 kW per wheel. Subsequently, a wireless in-wheel prototype achieved a transmission power of 12 kW per wheel.

[0003] However, there is an important technical problem in existing wireless electromagnetic drive devices: to ensure the stable operation and high transmission efficiency of wireless electromagnetic drive devices, it is necessary to ensure the stability of the mutual inductance between the primary and secondary coils. In existing wireless electromagnetic drive structures, in a vehicle driven by an in-wheel motor based on wireless electromagnetic drive, due to the vibration of the suspension spring, there are inevitable, frequent, and large-range relative position changes between the primary and secondary coils. Summary of the Invention

[0004] The purpose of the present invention is to provide a wireless electromagnetic drive electromagnetic automatic centering device and method, which can achieve real-time centering of the primary coil and the secondary coil, thereby ensuring the stability of energy transmission in the wireless electromagnetic drive system.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A wireless electromagnetic drive electromagnetic automatic centering device, the device includes: a primary support structure, a primary control box, a primary coil, a secondary coil, a secondary control box, a wheel hub motor, a wheel support suspension, and a wheel;

[0007] The primary support structure includes a support base plate, a slide rail provided on the surface of the support base plate, two spring support members, two tension springs, and a slider provided on the first surface of the primary control box and slidably connected to the slide rail;

[0008] The support base plate is fixedly connected to the vehicle body; one end of each of the two spring support members is fixedly connected to the support base plate, the other ends of the two spring support members are respectively connected to one ends of the two tension springs in a one-to-one correspondence, and the other ends of the two tension springs are respectively connected to two side edges of the primary control box in a one-to-one correspondence; the two side edges of the primary control box are two side edges adjacent to the first surface of the primary control box;

[0009] The second surface of the primary control box is fixedly connected to the primary coil, the secondary coil is fixedly connected to the first surface of the secondary control box, the second surface of the secondary control box is fixedly connected to the wheel hub motor, the wheel hub motor is connected to the wheel shaft, one end of the wheel support suspension is connected to the vehicle body, and the other end of the wheel support suspension is fixedly connected to the wheel hub motor; in the stress-free state, the primary coil and the secondary coil are aligned in the vertical direction; the first surface and the second surface of the primary control box are two relatively arranged surfaces of the primary control box; the first surface and the second surface of the secondary control box are two relatively arranged surfaces of the secondary control box.

[0010] The primary control box is provided with primary power electronic devices and a primary controller, the primary controller is connected to the primary power electronic devices, and the primary electronic devices are connected to the primary coil.

[0011] The primary controller is configured to calculate the direct current amount corresponding to the compensation electromagnetic force for offsetting the relative movement, and superimpose the direct current amount with the alternating current amount that satisfies the motor power output to obtain a switching state signal for controlling the primary power electronic devices and the secondary power electronic devices, so as to control the primary power electronic devices and the secondary power electronic devices to perform switching control operations, such that under the action of the compensation electromagnetic force generated between the primary coil and the secondary coil, the primary control box moves on the slide rail to realize the real-time centering of the primary coil and the secondary coil.

[0012] Optionally, the device further includes a wheel shock-absorbing spring; one end of the wheel shock-absorbing spring is connected to the vehicle body, and the other end of the wheel shock-absorbing spring is fixedly connected to the wheel support suspension.

[0013] Optionally, the primary control box is further provided with a primary compensation capacitor; the secondary control box is provided with secondary power electronic devices, a secondary controller, a secondary compensation capacitor and a motor controller;

[0014] The primary power electronic devices are respectively connected to an on-vehicle DC power supply, the primary controller and the primary compensation capacitor; the primary compensation capacitor is connected to the primary coil;

[0015] The secondary side coil is connected to the secondary side compensation capacitor, and the secondary side electronic devices are respectively connected to the secondary side compensation capacitor, the secondary side controller, and the motor controller; the motor controller is also connected to the secondary side controller and the wheel hub motor.

[0016] Optionally, the primary side power electronic device is a primary side inverter; the secondary side power electronic device is a secondary side controlled rectifier bridge.

[0017] The present invention also provides a wireless electromagnetic drive electromagnetic automatic centering method for a wireless electromagnetic drive electromagnetic automatic centering device, and the method includes:

[0018] Calculate the mutual inductance coefficient between the primary side coil and the secondary side coil;

[0019] Determine the relative motion law between the primary side coil and the secondary side coil according to the relationship table between the mutual inductance coefficient and the relative position between the primary and secondary coils, and calculate the compensating electromagnetic force between the coils to offset the relative motion according to the relative motion law between the primary and secondary coils;

[0020] Determine the direct current value of the compensating electromagnetic force generated by the primary side coil and the secondary side coil;

[0021] Obtain the motor side power demand value input by the driver on the vehicle side and determine the alternating current value that satisfies the motor power output according to the motor side power demand value;

[0022] Superimpose the direct current value and the alternating current value to obtain the switching state signals for controlling the primary side power electronic device in the primary side control box and the secondary side power electronic device in the secondary side control box;

[0023] Control the primary side power electronic device and the secondary side power electronic device to perform switching control operations according to the switching state signals; after the primary side power electronic device and the secondary side power electronic device perform switching control operations, under the action of the high-frequency electromagnetic field of the primary side coil and the electromagnetic field of the secondary side coil, the compensating electromagnetic force is generated between the primary side coil and the secondary side coil, and under the action of the compensating electromagnetic force, the primary side coil moves on the slide rail of the primary side support structure to achieve real-time centering with the secondary side coil.

[0024] Optionally, the calculation of the mutual inductance coefficient between the primary side coil and the secondary side coil specifically includes:

[0025] Obtain the primary side voltage value and primary side current value of the primary side coil and the secondary side voltage value and secondary side current value of the secondary side coil in real time;

[0026] Identify the mutual inductance coefficient between the primary and secondary coils in real time according to the primary side voltage value, the primary side current value, the secondary side voltage value, and the secondary side current value.

[0027] According to the specific embodiments provided by the present invention, the following technical effects are disclosed by the present invention:

[0028] The present invention discloses a wireless electromagnetic drive electromagnetic automatic centering device and method. The device includes: a primary side support structure, a primary side control box, a primary side coil, a secondary side coil, a secondary side control box, a wheel hub motor, a wheel support suspension, and a wheel; the primary side support structure includes a support base plate, a slide rail provided on the surface of the support base plate, two spring support members, two tension springs, and a slider for realizing the sliding connection between the primary side control box and the slide rail; the support base plate is fixedly connected to the vehicle body; one end of each of the two spring support members is fixedly connected to the support base plate, and the other ends are respectively connected to one ends of the two tension springs in a one-to-one correspondence, and the other ends are respectively connected to two sides of the primary side control box in a one-to-one correspondence; the primary side control box is connected to the primary side coil, and the primary side control box is provided with primary side power electronic devices and a primary side controller. The primary side controller is used to calculate the direct current corresponding to the compensation electromagnetic force for offsetting the relative movement between the coils, and combine with the motor power demand to obtain a switching state signal to control the operation of the primary and secondary side power electronic devices, so that under the action of the compensation electromagnetic force generated between the primary and secondary side coils, the primary side control box moves on the slide rail to realize the real-time centering of the primary side coil and the secondary side coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0030] Figure 1 It is an exploded structural schematic diagram of a wireless electromagnetic drive electromagnetic automatic centering device provided in Embodiment 1 of the present invention;

[0031] Figure 2 It is an overall structural schematic diagram of a wireless electromagnetic drive electromagnetic automatic centering device provided in Embodiment 1 of the present invention;

[0032] Figure 3 It is an overall schematic diagram of the primary side support structure provided in Embodiment 1 of the present invention;

[0033] Figure 4 It is a topology diagram of a wheel hub motor drive system based on wireless electromagnetic drive technology provided in Embodiment 1 of the present invention;

[0034] Figure 5 It is a compensation electromagnetic force and alternating current control flow chart provided in Embodiment 2 of the present invention;

[0035] Figure 6Flowchart of a wireless electromagnetic drive electromagnetic automatic centering method provided in Embodiment 2 of the present invention.

[0036] Reference numerals:

[0037] Primary side support structure - 1, support base plate - 101, slide rail - 102, spring support - 103, tension spring - 104, primary side control box - 2, primary side power electronic device - 201, primary side compensation capacitor - 202, primary side coil - 3, secondary side coil - 4, secondary side control box - 5, secondary side compensation capacitor - 501, secondary side power electronic device - 502, motor controller - 503, wheel support suspension - 6, wheel shock absorber spring - 7, wheel hub motor - 8, wheel - 9. Detailed implementation manners

[0038] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0039] The purpose of the present invention is to provide a wireless electromagnetic drive electromagnetic automatic centering device and method. By setting the primary side support structure, real-time centering of the primary side coil and the secondary side coil can be achieved under the action of the compensation electromagnetic force that offsets the relative movement between the coils, thereby ensuring the stable energy transmission of the wireless electromagnetic drive system.

[0040] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0041] Embodiment 1

[0042] As Figure 1 and 2 shown, the present invention provides a wireless electromagnetic drive electromagnetic automatic centering device, and the device includes: a primary side support structure 1, a primary side control box 2, a primary side coil 3, a secondary side coil 4, a secondary side control box 5, a wheel hub motor 8, a wheel support suspension 6, and a wheel 9.

[0043] The primary side support structure 1 is rigidly connected to the vehicle body. It is connected to the box through a spring and has the freedom to move up and down under the action of force. In the traditional structure, the primary side control box 2 and the primary side coil 3 are directly rigidly connected to the vehicle body without passing through the primary side support structure 1 and do not have the freedom in the vertical direction.

[0044] As Figure 3As shown, the primary side support structure 1 includes a support bottom plate 101, a slide rail 102 provided on the surface of the support bottom plate 101, two spring support members 103, two tension springs 104, and a slider provided on the first surface of the primary side control box 2 and slidably connected to the slide rail 102. The primary side control box 2 can move up and down on the slide rail 102.

[0045] The support bottom plate 101 is fixedly connected to the vehicle body, and the support bottom plate 101 can be integrally provided with the vehicle body; one end of each of the two spring support members 103 is fixedly connected to the support bottom plate 101, and the other end of each of the two spring support members 103 is respectively connected to one end of each of the two tension springs 104 in a one-to-one correspondence, and the other end of each of the two tension springs 104 is respectively connected to two side edges of the primary side control box 2 in a one-to-one correspondence; in a stress-free state, the position of the tension spring 104 aligns the primary and secondary side coils in the vertical position. The two side edges of the primary side control box 2 are two side edges adjacent to the first surface of the primary side control box 2.

[0046] The second surface of the primary side control box 2 is fixedly connected (rigidly connected) to the primary side coil 3, the secondary side coil 4 is fixedly connected to the first surface of the secondary side control box 5, the second surface of the secondary side control box 5 is fixedly connected to the wheel hub motor 8, the wheel hub motor 8 is axially connected to the wheel 9, one end of the wheel support suspension 6 is connected to the vehicle body, and the other end of the wheel support suspension 6 is fixedly connected to the wheel hub motor 8; in the stress-free state of the tension spring 104, the primary side coil 3 and the secondary side coil 4 are aligned in the vertical direction; the first surface and the second surface of the primary side control box 2 are two relatively arranged surfaces of the primary side control box 2; the first surface and the second surface of the secondary side control box 5 are two relatively arranged surfaces of the secondary side control box 5.

[0047] As Figure 1 shown, on the secondary side wheel side: the left side of the wheel support suspension 6, the upper part of the wheel shock absorber spring 7 are rigidly connected to the vehicle body, and the right side of the wheel support suspension 6 is connected to the wheel hub motor 8. Other secondary side electrical and mechanical components, including the secondary side coil 4 and the secondary side control box 5, the secondary side control box 5 is fixed on the wheel hub motor 8. The secondary side control box 5 integrates secondary side power electronic devices 502, secondary side compensation capacitors 501, motor controllers 503 and secondary side controllers, and the rotating shaft of the wheel 9 is connected to the output rotating shaft of the wheel hub motor 8. The secondary side coil 4 is connected to the secondary side compensation capacitor 501, and the secondary side electronic devices are respectively connected to the secondary side compensation capacitor 501, the secondary side controller and the motor controller 503; the motor controller 503 is also connected to the secondary side controller and the wheel hub motor 8. The secondary side power electronic device 502 is a secondary side controllable rectifier bridge.

[0048] Devices on the wheel side: The secondary coil 4, the secondary control box 5, and the wheel hub motor 8 move up and down synchronously with the vibration of the wheel 9 during vehicle driving.

[0049] Regarding the structure inside the primary control box 2, the primary power electronic device 201 and the primary controller are provided inside the primary control box 2. The primary controller is connected to the primary power electronic device 201, and the primary power electronic device is connected to the primary coil 3.

[0050] As Figure 4 shown, a primary compensation capacitor 202 is also provided inside the primary control box 2; a secondary power electronic device 502, a secondary controller, a secondary compensation capacitor 501, and a motor controller 503 are provided inside the secondary control box 5. The primary power electronic device 201 is respectively connected to the vehicle-mounted DC power supply, the primary controller, and the primary compensation capacitor 202; the primary compensation capacitor 202 is connected to the primary coil 3. More specifically, the primary power electronic device 201 is a primary inverter.

[0051] When the wireless electromagnetic drive system operates, the vehicle-mounted DC power supply is converted into alternating current through the power electronic conversion device (primary power electronic device 201), the primary compensation capacitor 202, and the primary coil 3, generating a high-frequency electromagnetic field with the magnetic induction line direction passing through the center of the primary coil 3 and along the axial direction of the primary coil 3.

[0052] To achieve the effect of vehicle body shock absorption, the device is also provided with a wheel shock absorption spring 7. One end of the wheel shock absorption spring 7 is connected to the vehicle body, and the other end of the wheel shock absorption spring 7 is fixedly connected to the wheel support suspension 6. Since the support bottom plate 101 of the primary support structure 1 is fixedly connected to the vehicle body, for the end of the wheel shock absorption spring 7 that needs to be fixedly connected to the vehicle body, this end can be fixedly connected to the support bottom plate 101 of the primary support structure 1, and the same effect of fixedly connecting the wheel shock absorption spring 7 to the vehicle body can be achieved.

[0053] The primary controller is used to calculate the direct current corresponding to the compensation electromagnetic force that cancels the relative movement between the coils, and superimpose the direct current with the alternating current that meets the motor power output to obtain the switching state signals for controlling the primary power electronic device 201 and the secondary power electronic device 502, so as to control the primary power electronic device 201 and the secondary power electronic device 502 to perform switching control operations, so that under the action of the compensation electromagnetic force generated between the primary coil 3 and the secondary coil 4, the primary control box 2 moves on the slide rail 102 to realize the real-time centering of the primary coil 3 and the secondary coil 4.

[0054] Compared with the existing wireless electromagnetic drive technology, when applying the wireless electromagnetic drive technology in the present invention, an additional DC component is generated on the coil, so that the centering of the coil can be achieved based on the electromagnetic force generated by this DC component.

[0055] Apply the electromagnetic automatic centering device of this embodiment to a vehicle driven by a hub motor based on wireless electromagnetic drive. In this vehicle structure, there is no cable connection between the vehicle body and the wheel 9 integrated with the hub motor and its control system, but wireless electromagnetic drive technology is used for power supply, improving the adaptability of the vehicle to harsh environments. Wireless electromagnetic drive is based on the principle of magnetic coupling. The primary magnetic coupling structure is connected to the vehicle body side, and the secondary magnetic coupling structure is connected to the wheel 9, located on both sides of the suspension of the vehicle wheel respectively. It can not only achieve wireless energy transmission based on high-frequency alternating current, but also achieve the function of electromagnetic force generation based on direct current, and combine with a specially designed mechanical structure to realize the real-time centering of the primary and secondary coils, ensuring the stability of wireless electromagnetic drive power transmission.

[0056] In this embodiment, the connection between the primary coil 3 and the vehicle body is no longer a traditional rigid connection, but through the slide rail 102 and the tension spring 104, so that the primary coil 3 has a degree of freedom of movement in the vertical direction, and has the ability to perform real-time centering of the primary and secondary coils in the case where the secondary coil 4 moves up and down under the influence of the vehicle wheel shock absorber. With the electromagnetic automatic centering device of this embodiment, the existing wireless electromagnetic drive coil is reused, and electromagnetic force is generated by passing direct current into the coil, and the electromagnetic force is used to make the primary control box 2 move relative to the primary support structure 1 to achieve real-time centering. Among them, the steps of electromagnetic force calculation are completed by steps 211, 212, 213, and 215 in Figure 5 Example 2.

[0057] Example 2

[0058] The following details the control method for real-time centering of the primary and secondary coils. As Figure 4 shown, it is a topology diagram (schematic diagram) of a hub motor drive system based on wireless electromagnetic drive technology. The drive unit of the wireless electromagnetic drive system based on the electromagnetic automatic centering device consists of two parts: the primary side (vehicle body side) and the secondary side (wheel side).

[0059] The wireless electromagnetic drive system is divided into two parts: the vehicle body side and the wheel side. On the vehicle body side, the DC power supply is connected to the vehicle-mounted battery to provide the same DC power supply as the vehicle's DC bus for the system. The DC power supply is converted into alternating current through the primary inverter. The frequency and phase of the alternating current are controlled in real time by the signal processing unit in the vehicle-mounted control module (primary controller) by controlling the power electronic switching devices in the primary inverter. The alternating current resonates in the high-frequency resonant circuit composed of the primary compensation capacitor 202 and the primary coil 3 (i.e., the inductance part in the magnetic coupling resonance) to form a high-frequency electromagnetic field. The energy is transmitted by the high-frequency electromagnetic field to the secondary coil 4, and an alternating current is excited in the secondary resonant circuit composed of the secondary coil 4 and the secondary compensation capacitor 501. Through the action of the secondary controllable rectifier bridge, it is converted into direct current to supply the motor controller 503. Through the action of the motor controller 503, it is converted into three-phase alternating current and transmitted to the wheel hub motor 8. The stability of the DC voltage on the input side of the motor controller 503 is achieved by the signal processing unit in the wheel side control module (secondary controller) by controlling the power electrical switching devices in the secondary controllable rectifier bridge. The output torque and speed regulation of the wheel hub motor 8 are achieved by the signal processing unit in the wheel side control module by controlling the power electrical switching devices in the motor controller 503.

[0060] During system operation, the vehicle-mounted DC power supply is converted into alternating current through the primary power electronic device 201, the primary compensation capacitor 202, and the primary coil 3, generating a high-frequency electromagnetic field with the magnetic induction line direction passing through the center of the primary coil 3. The control main body of the high-frequency electromagnetic field is the primary controller (which can be called the primary control signal processor / computer) connected to the primary control box 2 equipped with the primary power electronic device 201. The primary controller controls the switching of the power electronic devices in the primary control box 2 by generating high-frequency switching signals, such as IGBT (Insulated Gate Bipolar Transistor) or MOSFET (metal-oxide-semiconductor field-effect transistor), and then controls the switching on and off of the circuit to generate an alternating current signal.

[0061] Compared with the traditional wireless electromagnetic drive system, in the present invention, the primary controller in the primary control box 2 not only controls the conversion of direct current into an alternating current signal in the control algorithm, but also realizes the automatic control of the electromagnetic force between the primary and secondary coils. The specific electromagnetic force (compensation electromagnetic force) and alternating current control process are as Figure 5 shown.

[0062] The specific control method is as Figure 6 shown. The present embodiment provides a wireless electromagnetic drive electromagnetic automatic centering method, and the method includes: (Steps S1 to S6 are completed by the primary controller)

[0063] S1: Calculate the mutual inductance coefficient between the primary coil 3 and the secondary coil 4 (corresponding to Figure 5 step 211).

[0064] Among them, step S1 specifically includes:

[0065] (1) Obtain the primary voltage value and primary current value of the primary coil 3 and the secondary voltage value and secondary current value of the secondary coil 4 in real time.

[0066] The primary controller in the primary control box 2 collects the corresponding voltages and currents through current sensors and voltage sensors respectively installed on the primary and secondary coils.

[0067] (2) Identify the mutual inductance coefficient between the primary and secondary coils in real time according to the primary voltage value, the primary current value, the secondary voltage value and the secondary current value.

[0068] S2: Determine the relative motion law between the primary and secondary coils according to the relationship table between the mutual inductance coefficient and the relative position between the primary and secondary coils, and calculate the compensating electromagnetic force between the coils to offset the relative motion according to the relative motion law between the primary and secondary coils (corresponding to Figure 5 etep 212).

[0069] It is different for each coil. Generally speaking, when the primary and secondary coils are completely aligned, the mutual inductance coefficient is the largest. After there is a position offset, the mutual inductance coefficient gradually decreases. After the coils are produced, the mutual inductance coefficient only depends on the relative position between the coils. The specific relationship table between the relative positions of the primary and secondary coils is determined through experiments.

[0070] The primary control box 2 and the primary support structure 1 are connected by a tension spring 104. When the primary control box 2 is subjected to a force in the form of a pulse (that is, the electromagnetic force generated by the direct current in the coils acting on the primary coil 3 and the secondary coil 4), it will pull the tension spring 104 and move relative to the slide rail 102 in the primary support structure 1.

[0071] S3: Determine the direct current value for the primary coil 3 and the secondary coil 4 to generate the compensating electromagnetic force between the coils (corresponding to Figure 5 step 213).

[0072] The compensating electromagnetic force between the coils controlled by the direct current value realizes the real-time alignment of the wireless electromagnetic drive structure under the up and down movement state of the wheel 9 by means of the structure in the primary support structure 1 that allows the primary coil 3 to move freely up and down, achieving the goal of improving the overall efficiency and dynamic performance of the system.

[0073] S4: Obtain the motor-side power demand value input by the driver on the vehicle side and determine the alternating current value that satisfies the motor power output according to the motor-side power demand value (corresponding toFigure 5 Step 214 (which also exists in existing wireless power transmission schemes).

[0074] S5: Superimpose the direct current and the alternating current (i.e., superimpose the DC and AC waveform signals) to obtain a switching state signal for controlling the primary power electronic device 201 in the primary control box 2 and the secondary power electronic device 502 in the secondary control box 5 (corresponding to Figure 5 Step 215).

[0075] S6: Control the primary power electronic device 201 and the secondary power electronic device 502 to perform switching control operations according to the switching state signal.

[0076] After the primary power electronic device 201 and the secondary power electronic device 502 perform switching control operations, under the action of the high-frequency electromagnetic field of the primary coil 3 and the electromagnetic field of the secondary coil 4, a compensation electromagnetic force is generated between the primary coil 3 and the secondary coil 4. Under the action of the compensation electromagnetic force, the primary coil 3 moves on the slide rail 102 of the primary support structure 1 to achieve real-time alignment with the secondary coil 4.

[0077] When the primary coil 3 is subjected to the action of the compensation electromagnetic force, it can vibrate up and down in the vertical dimension, so that the primary coil 3 maintains a relatively stable position with respect to the secondary coil 4 (i.e., the wheel 9) to the greatest extent, ensuring the stability of wireless electromagnetic drive power transmission. The electromagnetic force is generated on the coil in the magnetic field, and here it is mainly the compensation electromagnetic force that makes the primary coil 3 move up and down. The secondary coil 4 is fixed on the wheel side, and the electromagnetic force cannot make it move.

[0078] More comprehensively, after the primary power electronic device 201 and the secondary power electronic device 502 perform switching control operations, the on-vehicle direct current is converted into alternating current through the primary power electronic device 201, the primary compensation capacitor 202, and the primary coil 3. The primary coil 3 generates a high-frequency electromagnetic field, and the high-frequency electromagnetic field wirelessly transmits energy to the secondary coil 4. It is converted into regulated DC power supply through the secondary power electronic device 502 (controlled rectifier bridge) in the secondary control box 5 and supplied to the motor controller 503 also located in the secondary control box 5. The motor controller 503 combines the motor control reference quantities (speed, torque, etc.) issued by the whole vehicle to convert the direct current into three-phase alternating current to drive the wheel hub motor 8, and the wheel hub motor 8 works to drive the wheel 9 to move, finally completing the wireless electromagnetic drive process. This part of the content needs to be jointly completed by the secondary controller (secondary signal processor / computer) and the motor controller 503 in the secondary control box 5.

[0079] In a traditional wireless electromagnetic drive device, the magnetic coupling structure coil can only provide the function of energy transmission. The present invention uses a special primary-secondary magnetic coupling structure coil structure design scheme and a coil power electronic device control algorithm, and utilizes the electromagnetic force of the coil itself to achieve real-time automatic centering of the primary-secondary magnetic coupling structure coil under the working conditions of wireless electromagnetic drive, improving the stability and overall working efficiency of a hub motor-driven vehicle system based on wireless electromagnetic drive.

[0080] The magnetic coupling coils (primary coil 3 and secondary coil 4) in the wireless electromagnetic drive electromagnetic automatic centering device in the present invention play two roles simultaneously: First, wireless energy transmission based on alternating current; second, electromagnetic force generation function based on direct current (the direct current amount in step S3), and real-time centering of the primary and secondary coils is achieved by combining a specially designed mechanical structure.

[0081] Each embodiment focuses on the differences from other embodiments, and the same or similar parts among the embodiments can be referred to each other.

[0082] Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation on the present invention.

Claims

1. A wireless electromagnetic drive electromagnetic automatic centering device, characterized in that, The device includes: a primary side support structure, a primary side control box, a primary side coil, a secondary side coil, a secondary side control box, a wheel hub motor, a wheel support suspension, and a wheel; The primary side support structure includes a support base plate, a slide rail provided on the surface of the support base plate, two spring support members, two tension springs, and a slider provided on the first surface of the primary side control box and slidably connected to the slide rail; The support base plate is fixedly connected to the vehicle body; one end of each of the two spring support members is fixedly connected to the support base plate, the other ends of the two spring support members are respectively connected to one end of the two tension springs in a one-to-one correspondence, and the other ends of the two tension springs are respectively connected to two sides of the primary side control box in a one-to-one correspondence; the two sides of the primary side control box are two sides adjacent to the first surface of the primary side control box; The second surface of the primary side control box is fixedly connected to the primary side coil, the secondary side coil is fixedly connected to the first surface of the secondary side control box, the second surface of the secondary side control box is fixedly connected to the wheel hub motor, the wheel hub motor is connected to the wheel shaft, one end of the wheel support suspension is connected to the vehicle body, and the other end of the wheel support suspension is fixedly connected to the wheel hub motor; in the stress-free state, the primary side coil and the secondary side coil are aligned in the vertical direction; the first surface and the second surface of the primary side control box are two relatively arranged surfaces of the primary side control box; the first surface and the second surface of the secondary side control box are two relatively arranged surfaces of the secondary side control box; The primary side control box is provided with primary side power electronic devices and a primary side controller, the primary side controller is connected to the primary side power electronic devices, and the primary side power electronic devices are connected to the primary side coil; The primary side controller is used to calculate the direct current corresponding to the compensation electromagnetic force for offsetting the relative movement between the coils, and superimpose the direct current with the alternating current that satisfies the motor power output to obtain a switching state signal for controlling the primary side power electronic devices and the secondary side power electronic devices, so as to control the primary side power electronic devices and the secondary side power electronic devices to perform switching control operations, so that under the action of the compensation electromagnetic force generated between the primary side coil and the secondary side coil, the primary side control box moves on the slide rail to realize the real-time centering of the primary side coil and the secondary side coil.

2. The wireless electromagnetic drive electromagnetic automatic centering device according to claim 1, characterized in that The device further includes a wheel shock-absorbing spring; one end of the wheel shock-absorbing spring is connected to the vehicle body, and the other end of the wheel shock-absorbing spring is fixedly connected to the wheel support suspension.

3. The wireless electromagnetic drive electromagnetic automatic centering device according to claim 1, characterized in that, The primary side control box is further provided with a primary side compensation capacitor; the secondary side control box is provided with secondary side power electronic devices, a secondary side controller, a secondary side compensation capacitor, and a motor controller; The primary side power electronic devices are respectively connected to an in-vehicle DC power supply, the primary side controller, and the primary side compensation capacitor; the primary side compensation capacitor is connected to the primary side coil; The secondary side coil is connected to the secondary side compensation capacitor, and the secondary side power electronic devices are respectively connected to the secondary side compensation capacitor, the secondary side controller and the motor controller; the motor controller is further connected to the secondary side controller and the in-wheel motor.

4. The wireless electromagnetic drive electromagnetic automatic centering device according to claim 3, characterized in that, The primary side power electronic device is a primary side inverter; the secondary side power electronic device is a secondary side controlled rectifier bridge.

5. A wireless electromagnetic drive electromagnetic automatic centering method for the wireless electromagnetic drive electromagnetic automatic centering device according to any one of claims 1 to 4, characterized in that, The method includes: Calculating the mutual inductance coefficient between the primary side coil and the secondary side coil; Determining the relative motion law between the primary side coil and the secondary side coil according to the relationship table between the mutual inductance coefficient and the relative position between the primary and secondary coils, and calculating the compensation electromagnetic force between the coils to offset the relative motion according to the relative motion law between the primary and secondary coils; Determining the direct current value of the primary side coil and the secondary side coil that generates the compensation electromagnetic force between the coils; Obtaining the motor side power demand value input by the driver on the vehicle side and determining the alternating current value that satisfies the motor power output according to the motor side power demand value; Superimposing the direct current value and the alternating current value to obtain the switching state signals for controlling the primary side power electronic device in the primary side control box and the secondary side power electronic device in the secondary side control box; Controlling the primary side power electronic device and the secondary side power electronic device to perform switching control operations according to the switching state signals; after the primary side power electronic device and the secondary side power electronic device perform the switching control operations, under the action of the high-frequency electromagnetic field of the primary side coil and the electromagnetic field of the secondary side coil, the compensation electromagnetic force between the primary side coil and the secondary side coil is generated, and under the action of the compensation electromagnetic force between the coils, the primary side coil moves on the slide rail of the primary side support structure to achieve real-time alignment with the secondary side coil.

6. The wireless electromagnetic drive electromagnetic automatic centering method according to claim 5, wherein, The calculation of the mutual inductance coefficient between the primary side coil and the secondary side coil specifically includes: Obtaining in real time the primary side voltage value and primary side current value of the primary side coil and the secondary side voltage value and secondary side current value of the secondary side coil; Identifying in real time the mutual inductance coefficient between the primary and secondary coils according to the primary side voltage value, the primary side current value, the secondary side voltage value and the secondary side current value.

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