High-power-density electric field coupling type wireless charging structure

Abstract

The invention relates to an electric field coupling type wireless charging structure, in particular to a high-power-density electric field coupling type wireless charging structure. The invention aims to solve the problem of low power density of a coupling mechanism of an electric field coupling type wireless power transmission system. The device comprises a first energy emitting polar plate assembly, a second energy emitting polar plate assembly, a first energy receiving polar plate assembly, a second energy receiving polar plate assembly and a rotating shaft, the first energy emitting pole plate assembly and the first energy receiving pole plate assembly are vertically inserted to form a first reel type coupling unit, and the second energy emitting pole plate assembly and the second energy receiving pole plate assembly are vertically inserted to form a second reel type coupling unit. The first reel type coupling unit and the second reel type coupling unit are sequentially and fixedly arranged on a rotating shaft in a sleeving mode, and the rotating shaft is connected with rotation driving equipment. The invention belongs to the technical field of electric field coupling type wireless charging.

Description

Technical Field

[0001] The invention relates to an electric field coupling type wireless charging structure, belonging to the technical field of electric field coupling type wireless charging. Background Art

[0002] In special environments such as outer spacecraft, wind power generation, and oil drilling, rotating slip rings are required to power special equipment in a rotating state. Currently, most of the rotating slip rings used are conductive slip rings with physical contact, which have disadvantages such as high cost, wear during operation, and easy generation of abrasive debris, which restrict the service life of rotating equipment. Wireless power transmission technology, with its advantages of non-contact power supply, can fundamentally solve the problems of short circuit between rings and electrostatic discharge in the slip ring power supply method, thereby improving the reliability of the equipment power supply unit. At the same time, by optimizing the design of the wireless power supply coupling mechanism and replacing multiple conductive rings, the overall weight of the power supply unit can be effectively reduced to achieve a lightweight design. With the development of this technology and its wide application in electric vehicles and home appliances, it has received great attention in the aerospace field in recent years.

[0003] In recent years, scholars from various countries have conducted research on the application of inductive power transfer (IPT) wireless power supply technology to solve the problem of wireless power supply for rotating slip rings, and have achieved some results. However, it is also found that the IPT system is restricted by problems such as power density and EMI: for example, the changing magnetic field induces eddy currents, resulting in power loss; the energy transfer magnetic field is easily radiated to the outside of the WPT system, increasing the EMI problem; IPT usually requires twisted wires to reduce the skin effect, and requires ferrite to guide the magnetic field, which increases the weight and cost of the system. The capacitive power transfer (CPT) technology has the advantages of strong anti-electromagnetic interference, small size, and light weight, which is conducive to miniaturization and heat dissipation design, and is easy to achieve simultaneous transmission of energy and signal. It has great potential in the field of rotating wireless power supply in special environments. Summary of the invention

[0004] The present invention aims to solve the problem that the magnetic field coupling type wireless power supply technology usually requires twisted wires to reduce the skin effect and requires ferrite to guide the magnetic field, which increases the weight and cost of the system, and further proposes a high power density electric field coupling type wireless charging structure.

[0005] The technical solution adopted by the present invention to solve the above problems is: the present invention comprises a first energy emitting plate assembly, a second energy emitting plate assembly, a first energy receiving plate assembly, a second energy receiving plate assembly and a rotating shaft;

[0006] The first energy emitting plate assembly and the first energy receiving plate assembly are plugged in up and down to form a first roll-type coupling unit, and the second energy emitting plate assembly and the second energy receiving plate assembly are plugged in up and down to form a second roll-type coupling unit. The first roll-type coupling unit and the second roll-type coupling unit are fixedly mounted on the rotating shaft in sequence, and the rotating shaft is connected to the rotating drive device.

[0007] Further, the first energy emitter plate assembly includes a first disk and a plurality of first energy emitter plates;

[0008] The first energy emitting plate is annular, and a plurality of first energy emitting plates are sequentially arranged from the inside to the outside, and the upper surface of each first energy emitting plate is fixedly connected to the lower surface of the first disk.

[0009] Further, the first energy receiving plate assembly includes a second disk and a plurality of first energy receiving plates;

[0010] The first energy receiving plate is annular, and multiple first energy receiving plates are sequentially arranged from the inside to the outside. The lower surface of each first energy receiving plate is fixedly connected to the upper surface of the second disk, and multiple first energy emitting plates are staggered and plugged together with multiple first energy receiving plates.

[0011] Further, the second energy emitter plate assembly includes a third disk and a plurality of second energy emitter plates;

[0012] The second energy emitting plate is annular, and a plurality of second energy emitting plates are sequentially arranged from the inside to the outside, and the upper surface of each second energy emitting plate is fixedly connected to the lower surface of the third disk.

[0013] Further, the second energy receiving plate assembly includes a fourth disk and a plurality of second energy receiving plates;

[0014] The second energy receiving plate is annular, and multiple second energy receiving plates are sequentially arranged from the inside to the outside. The lower surface of each second energy receiving plate is fixedly connected to the upper surface of the fourth disk, and multiple second energy emitting plates are staggered and plugged together with multiple second energy receiving plates.

[0015] Furthermore, the width of the first energy emitting plate and the first energy receiving plate are both 80 mm.

[0016] Furthermore, the width of the second energy emitting plate and the second energy receiving plate are both 80 mm.

[0017] Furthermore, a distance between a lower surface of the first roll-type coupling unit and an upper surface of the second roll-type coupling unit is 116 mm.

[0018] The beneficial effects of the present invention are as follows: by adopting the electric field coupling wireless power transmission scheme, designing a reel-type coupling mechanism, and adopting a bilateral LCLC type resonant compensation network, a constant voltage output independent of the load can be achieved, and the energy dissipation in the energy transmission process can be greatly reduced; compared with the traditional cylindrical structure, the equivalent coupling mutual capacitance value C of the reel-type coupling mechanism is M The power density increased by 380.82%, the weight power density increased by 27%, and the volume power density increased by 327%;

[0019] Traditional aerospace power supply slip rings use contact power supply, which has high system cost, heavy weight, easy wear and short life. The existing wireless power supply slip rings based on magnetic coupling wireless power transmission technology have defects such as large eddy current loss and high heat generation. The aerospace power supply slip rings using electric field coupling wireless power transmission technology have strong anti-electromagnetic interference, small size, light weight and low cost. They fundamentally overcome the wear and chip problems in the power supply of spacecraft rotating slip rings, while reducing the cost and weight of the power supply device, providing a very potential solution for improving the service life of the spacecraft power supply device.

[0020] The present invention adopts a reel-type coupling mechanism. Since the energy emitting plate and the energy receiving plate are arranged in an interlaced manner, both sides of the energy emitting plate are coupled with energy receiving plates, and the plate area is fully utilized. Under the condition of generating the same coupling capacitance, the required coupling plate area is smaller, which can greatly reduce the weight and cost of the coupling plate. 3. The reel-type coupling mechanism is adopted. Since the space inside the cylinder is fully utilized and multiple coupling surfaces are superimposed, the space volume of the coupling mechanism is fully utilized, which is conducive to the miniaturization design of the system;

[0021] The present invention adopts a bilateral LCLC type resonant compensation network to achieve a constant voltage output that is independent of the load. Even if the spacecraft load fluctuates, the energy output can remain unchanged, thereby greatly improving the stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of the reel-type coupling unit;

[0023] Figure 2 It is a disassembled schematic diagram of the reel-type coupling unit;

[0024] Figure 3 It is a schematic diagram of a bilateral LCLC type resonant compensation network;

[0025] Figure 4 It is a schematic diagram of the six capacitors produced by the four-electrode plate;

[0026] Figure 5 It is a schematic diagram of a bilateral LCLC type resonant compensation network after decoupling the coupling unit according to a π-type equivalent network;

[0027] Figure 6 It is a schematic diagram of parameter setting of the reel-type coupling unit;

[0028] Figure 7 It is a schematic diagram of the parameter setting of the traditional cylinder coupling mechanism;

[0029] Figure 8 is a cross-sectional view of a first reel-type coupling unit;

[0030] Fig. 9 is a cross-sectional view of the second reel-type coupling unit. DETAILED DESCRIPTION

[0031] Specific implementation method 1: Figure 1 , Figure 2 , Figure 8 and Fig. 9 As shown, a high power density electric field coupling type wireless charging structure includes a first energy emitting plate assembly, a second energy emitting plate assembly, a first energy receiving plate assembly, a second energy receiving plate assembly and a rotating shaft;

[0032] The first energy emitting plate assembly and the first energy receiving plate assembly are plugged in up and down to form a first roll-type coupling unit, and the second energy emitting plate assembly and the second energy receiving plate assembly are plugged in up and down to form a second roll-type coupling unit. The first roll-type coupling unit and the second roll-type coupling unit are fixedly mounted on the rotating shaft in sequence, and the rotating shaft is connected to the rotating drive device.

[0033] Wherein, the first energy emitting plate assembly includes a first disk 2 and a plurality of first energy emitting plates P1;

[0034] The first energy emitting plate P1 is annular, and a plurality of first energy emitting plates P1 are sequentially arranged from the inside to the outside, and the upper surface of each first energy emitting plate P1 is fixedly connected to the lower surface of the first disc 2; the first energy receiving plate assembly includes a second disc 3 and a plurality of first energy receiving plates P3;

[0035] The first energy receiving plate P3 is annular, and multiple first energy receiving plates P3 are sequentially arranged from the inside to the outside. The lower surface of each first energy receiving plate P3 is fixedly connected to the upper surface of the second disk 3, and multiple first energy emitting plates P1 are staggered and plugged together with multiple first energy receiving plates P3.

[0036] Wherein, the second energy emitting plate assembly includes a third disk 4 and a plurality of second energy emitting plates P2;

[0037] The second energy emitting plate P2 is annular, and a plurality of second energy emitting plates P2 are sequentially arranged from the inside to the outside, and the upper surface of each second energy emitting plate P2 is fixedly connected to the lower surface of the third disk 4; the second energy receiving plate assembly includes a fourth disk 5 and a plurality of second energy receiving plates P4;

[0038] The second energy receiving plate P4 is annular, and multiple second energy receiving plates P4 are sequentially arranged from the inside to the outside. The lower surface of each second energy receiving plate P4 is fixedly connected to the upper surface of the fourth disk 5, and multiple second energy emitting plates P2 and multiple second energy receiving plates P4 are staggered and plugged together.

[0039] Among them, the width of the first energy emitting plate P1 and the first energy receiving plate P3 are both 80 mm;

[0040] The width of the second energy emitting plate P2 and the second energy receiving plate P4 are both 80 mm;

[0041] The distance between the lower surface of the first roll-type coupling unit and the upper surface of the second roll-type coupling unit is 116 mm.

[0042] The diameters of the first disc 2, the second disc 3, the third disc 4 and the fourth disc 5 are all 220 mm;

[0043] The distance between the bottom edge of the first energy emitting plate P1 and the upper surface of the second disk 3 is 10 mm;

[0044] The distance between the bottom edge of the second energy emitting plate P2 and the upper surface of the fourth disk 5 is 10 mm;

[0045] The distance between the top edge of the first energy receiving plate P3 and the lower surface of the first disk 2 is 10 mm;

[0046] The distance between the top edge of the second energy receiving plate P4 and the lower surface of the third disk 4 is 10 mm.

[0047] How it works

[0048] like Figure 1 As shown, the energy emitting plates and the energy receiving plates are arranged alternately, and both sides of the energy emitting plates are coupled with energy receiving plates; the top of the energy emitting plates and the bottom of the energy receiving plates are integrally connected with disks, and there is an opening in the center of the disk for passing the shaft; the energy emitting plates are connected to the rotating mechanism of the rotating equipment through bearings to maintain the rotating motion state; the energy receiving plates are connected to the rotating equipment body through the shaft and maintain a relatively static state with the rotating equipment body;

[0049] like Figure 2As shown, during the energy transmission process, the rotating first energy emitting plate P1 transmits electric energy to the first energy receiving plate P3 in a non-contact manner, and after flowing through the load, the energy is returned to the second energy emitting plate P2 through the second energy receiving plate P4, thereby completing the energy transmission process; the energy emitting and receiving plates are both composed of light-weight, low-cost, thin copper cylinders, which can reduce the weight and cost of the energy transmission system while meeting the mechanical strength requirements of the rotating mechanism; insulating materials are added to the outer surface of the emitter plate of the coupling mechanism to prevent electrical breakdown accidents during the energy transmission process and ensure the safety and stability of the system;

[0050] like Figure 3 As shown, the transmitter consists of two inductors L1 and L f1 And two capacitors C f1 and C ex1 The receiving end consists of two inductors L2 and L f2 And two capacitors C f2 and C ex2 Composition. in is the input AC power, U out is the output AC power supply. Due to the effect of compensation capacitor, the equivalent parallel capacitance of the energy input and output ports can be recorded as C in1 =C ex1 +C1, C in2 =C ex2 +C2. To analyze the parameter relationship of the resonant compensation network components, the coupling mechanism must first be modeled. Since the coupling mechanism can actually be considered to have two sets of "transmit-receive" plates, that is, a total of four metal plates. These four metal plates can generate six equivalent coupling capacitors;

[0051] like Figure 4 As shown, in order to simplify the calculation, the formula shown in formula (1) is used to decouple the six capacitors into three capacitors, and further form a π-type equivalent network. The bilateral LCLC resonant compensation network after decoupling the coupling mechanism according to the π-type network is as follows Figure 5 shown.

[0052]

[0053] When the system operates at the resonant frequency, the primary inductance L f1 With the primary capacitor C f1 The parallel resonance is formed, as shown in formula (2), at this time 1 / jωC f1 =jωL f1 , so the primary resonant inductance value is L in1 =L1-L f1 . Primary inductance L in1 , L f1 With C in1, C in2 , C M The secondary inductor L2 and C1, C2, C M Constitute parallel resonance, as shown in formula (3);

[0054]

[0055] The network can achieve constant voltage output regardless of load when the condition is satisfied, that is, ZPA (Zero Phase Angle). The relationship between U2 and U1 is shown in equation (4).

[0056]

[0057] Since the transmission power of the coupling mechanism is related to the equivalent mutual capacitance value C M So the mutual capacitance value C can be used M To reflect the power transmission situation. Therefore, the coupling capacitance value K under the unit weight of the coupling plate is used. G To reflect the weight power density of the energy transmission of the coupling mechanism, the coupling capacitance value K per unit volume of the coupling mechanism is used. V To reflect the volume power density of energy transmission of the coupling mechanism. That is: K G =C M / G, where G is the weight of the coupling mechanism; K V =C M / V, where V is the volume of the coupling mechanism.

[0058] A simulation model is established in Maxwell, where Figure 6 The reel coupling mechanism is provided. Figure 7 The traditional coupling mechanism is used as a control. The size and energy transmission distance of both are set to be 2mm, and the thickness of the coupling plate is 2mm. The material of the coupling plate is copper. Its density is ρ cu .

[0059] The equivalent coupling capacitance values ​​of the two structures are shown in Table 1 and Table 2. As can be seen from the table, the reel-type coupling mechanism increases the coupling capacitance C 13 and C 24 , while reducing the cross-coupling capacitance C 14 and C 23 , which is more conducive to energy transmission.

[0060] The six coupling capacitors are equivalently calculated using formula (1), and the three equivalent coupling capacitor values ​​are shown in Table 3. As can be seen from the table, the mutual capacitance value C of the winding structure is M It is 4.8 times that of the traditional cylindrical structure.

[0061] According to the simulation model parameters, the total weight G1 of the four coupling plates of the reel-type coupling mechanism is 517040πρcu , the total volume V1 of the two pairs of "transmitter-receiver" structures is 2178000πmm 3 ; Cylindrical coupling mechanism, the total weight G2 of the four coupling plates is 136960πρ cu , the total volume V2 of the two pairs of "transmitter-receiver" structures is 1936000πmm 3 The K of the two coupling mechanisms can be calculated G With K V As shown in Table 4. It can be seen from the table that the K of the roll structure G It is 27.6% larger than the traditional cylindrical structure, which means that the weight power density of the drum structure is 27.6% higher than that of the traditional cylindrical structure; V It is 4.27 times that of the traditional cylindrical structure, which means that the volume power density of the drum structure is 4.27 times that of the traditional cylindrical structure.

[0062] Table 1 Simulation results of six capacitance values ​​of traditional cylindrical coupling mechanism

[0063]

[0064] Table 2 Simulation results of six capacitance values ​​of the drum coupling mechanism

[0065]

[0066] Table 3 Three equivalent coupling capacitance values ​​after equivalent

[0067]

[0068] Table 4 K of two coupling mechanisms G With K V

[0069]

[0070]

[0071] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent replacement and improvement made to the above embodiments without departing from the content of the technical solution of the present invention, based on the technical essence of the present invention, within the spirit and principles of the present invention, still fall within the protection scope of the technical solution of the present invention.

Claims

1. A high power density electric field coupling wireless charging structure, characterized in that: It includes a first energy emitting plate assembly, a second energy emitting plate assembly, a first energy receiving plate assembly, a second energy receiving plate assembly and a rotating shaft; The first energy emitting plate assembly and the first energy receiving plate assembly are plugged in up and down to form a first roll-type coupling unit, and the second energy emitting plate assembly and the second energy receiving plate assembly are plugged in up and down to form a second roll-type coupling unit. The first roll-type coupling unit and the second roll-type coupling unit are fixedly mounted on the rotating shaft in sequence, and the rotating shaft is connected to the rotating drive device.

2. The high power density electric field coupling wireless charging structure according to claim 1, characterized in that: The first energy emitting plate assembly comprises a first disk (2) and a plurality of first energy emitting plates (P1); The first energy emitting plate (P1) is annular, and a plurality of first energy emitting plates (P1) are sequentially arranged from the inside to the outside, and the upper surface of each first energy emitting plate (P1) is fixedly connected to the lower surface of the first disc (2).

3. A high power density electric field coupling wireless charging structure according to claim 1 or 2, characterized in that: The first energy receiving plate assembly comprises a second disk (3) and a plurality of first energy receiving plates (P3); The first energy receiving plate (P3) is annular, and a plurality of first energy receiving plates (P3) are sequentially arranged from the inside to the outside, the lower surface of each first energy receiving plate (P3) is fixedly connected to the upper surface of the second disc (3), and the plurality of first energy emitting plates (P1) and the plurality of first energy receiving plates (P3) are staggered and plugged together.

4. The high power density electric field coupling type wireless charging structure according to claim 1, characterized in that: The second energy emitting plate assembly comprises a third disk (4) and a plurality of second energy emitting plates (P2); The second energy emitting plate (P2) is annular, and a plurality of second energy emitting plates (P2) are sequentially arranged from the inside to the outside, and the upper surface of each second energy emitting plate (P2) is fixedly connected to the lower surface of the third disk (4).

5. A high power density electric field coupling type wireless charging structure according to claim 1 or 4, characterized in that: The second energy receiving plate assembly comprises a fourth disk (5) and a plurality of second energy receiving plates (P4); The second energy receiving plate (P4) is annular, and a plurality of second energy receiving plates (P4) are sequentially arranged from the inside to the outside, the lower surface of each second energy receiving plate (P4) is fixedly connected to the upper surface of the fourth disk (5), and the plurality of second energy emitting plates (P2) and the plurality of second energy receiving plates (P4) are staggered and plugged together.

6. The high power density electric field coupling wireless charging structure according to claim 3, characterized in that: The width of the first energy emitting plate (P1) and the first energy receiving plate (P3) are both 80 mm.

7. The high power density electric field coupling wireless charging structure according to claim 5, characterized in that: The width of the second energy emitting plate (P2) and the second energy receiving plate (P4) are both 80 mm.

8. The high power density electric field coupling type wireless charging structure according to claim 1, characterized in that: The distance between the lower surface of the first roll-type coupling unit and the upper surface of the second roll-type coupling unit is 116 mm.

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