Integrated multi-channel coupler and modeling and parameter design method thereof

Abstract

The invention discloses an integrated multichannel coupler and a modeling and parameter design method thereof. The integrated multichannel coupler comprises a plurality of channels arranged side by side, each channel comprises a transmitting end pole plate group and a receiving end pole plate group, the transmitting end pole plate group comprises a first transmission pole plate and a second transmission pole plate, and the receiving end pole plate group comprises a third transmission pole plate and a fourth transmission pole plate; the first shielding plate and the second shielding plate can cover all the channels, the first shielding plate is located on the outer side, away from the receiving end polar plate group, of the transmitting end polar plate group, and the second shielding plate is located on the outer side, away from the transmitting end polar plate group, of the receiving end polar plate group. The integrated multi-channel coupler has the advantages that electric field radiation is reduced, compensation inductance is reduced, and meanwhile channel expansion is facilitated. According to the modeling method, the coupler full-capacitance model is simplified based on the controlled current source model, so that parameter design of the system is facilitated.

Description

Technical Field

[0001] The present invention belongs to the field of wireless charging, and more specifically, relates to an integrated multi-channel coupler and a modeling and parameter design method thereof. Background Art

[0002] Wireless power transfer (WPT) technology, which transfers energy through electric fields, magnetic fields, and microwaves, enables cable-free and intelligent power supply for devices. It has been widely used in fields such as electric vehicles, drones, and consumer electronics. Capacitive wireless power transfer (CWPT) technology, in particular, has attracted increasing attention due to its advantages, including a simple transmission mechanism, no eddy current losses, low cost, and lightweight.

[0003] Currently, due to the widespread use of power electronics in products such as electric vehicles, single-channel CWPT systems are unable to meet the power and voltage requirements. For example, EV charging power requirements can reach tens of kilowatts. Multi-channel CWPT systems combine multiple single-channel systems to increase output power. However, the coupler, the core of CWPT systems for wireless power transmission, urgently needs optimized design to improve safety and feasibility for high-power applications. Summary of the Invention

[0004] In view of the above defects or improvement needs of the prior art, the present invention provides an integrated multi-channel coupler and a modeling and parameter design method thereof.

[0005] To achieve the above object, according to a first aspect of the present invention, there is provided an integrated multi-channel coupler, comprising: n channels arranged side by side, n ≥2, each channel includes a transmitting end plate group and a receiving end plate group, the transmitting end plate group includes a first transmission plate and a second transmission plate, the receiving end plate group includes a third transmission plate and a fourth transmission plate, the first transmission plate and the third transmission plate are arranged in a positive coupling arrangement, and the second transmission plate and the fourth transmission plate are arranged in a positive coupling arrangement; The first shielding plate and the second shielding plate can cover all channels. The first shielding plate is located outside the transmitting end plate group away from the receiving end plate group, and the second shielding plate is located outside the receiving end plate group away from the transmitting end plate group.

[0006] Preferably, the first transmission plate, the second transmission plate, the third transmission plate, and the fourth transmission plate are all rectangular aluminum plates of the same size.

[0007] Preferably, adjacent channels are spaced at equal distances from each other.

[0008] According to a second aspect of the present invention, a modeling method for an integrated multi-channel coupler is provided, wherein a controlled current source model is established for the integrated multi-channel coupler. The controlled current source model includes n +1 controlled current source, and the first transmission plate is denoted as P i1 , the second transmission plate is marked as P i2 , the third transmission plate is marked as P i3 , the fourth transmission plate is recorded as P i4 , the first shielding plate is marked as P U , the second shielding plate is marked as P L , for the i controlled current sources, 1≤ i ≤ n , the first transmission plate P i1 , the second transmission plate P i2 Connected to the transmitter circuit to form a port i 1; The third transmission plate P i3 , the fourth transmission plate P i4 Connected to the receiving end circuit to form a port i 2. For the n +1 controlled current source, first shield P U and the second shielding plate P L Composed port s.

[0009] Preferably, the channel i Middle transmission plate x With transmission plate y The coupling capacitance between C i xy , subscript x and y Indicates the transmission plate number, x =1 or 2 or 3 or 4, y =1 or 2 or 3 or 4, the channel i Middle transmission plate x The coupling capacitance between the first shield plate and the first shield plate is defined as C is xU , the channel i Middle transmission plate xThe coupling capacitance between the shield plate and the second shield plate is defined as C is xL , the coupling capacitance between the first shielding plate and the second shielding plate is defined as C s UL , will i Channel transmission plate x With the k Channel transmission plate y The cross-coupling capacitance between C ik xy , port i The self-capacitance of 1 is recorded as , The calculation formula is: ; port i The self-capacitance of 2 is recorded as , The calculation formula is: ; aisle i Port a and channel k The mutual capacitance between port b is recorded as , The calculation formula is: .

[0010] According to a third aspect of the present invention, a parameter design method for an integrated multi-channel coupler is provided, comprising the steps of: A controlled current source model is established for the integrated multi-channel coupler, wherein the controlled current source model includes n +1 controlled current source, and the first transmission plate is denoted as P i1 , the second transmission plate is marked as P i2 , the third transmission plate is marked as P i3 , the fourth transmission plate is recorded as P i4 , the first shielding plate is marked as P U , the second shielding plate is marked as P L , for the i controlled current sources, 1≤ i ≤ n , the first transmission plate P i1 , the second transmission plate Pi2 Connected to the transmitter circuit to form a port i 1; The third transmission plate P i3 , the fourth transmission plate P i4 Connected to the receiving end circuit to form a port i 2. For the n +1 controlled current source, first shield P U and the second shielding plate P L Composition port s; Calculate self-capacitance and mutual capacitance based on the controlled current source model; The compensation inductance and capacitance connected at both ends of the coupler are determined based on the calculated self-capacitance and mutual capacitance.

[0011] Preferably, the channel i Middle transmission plate x With transmission plate y The coupling capacitance between C i xy , subscript x and y Indicates the transmission plate number, x =1 or 2 or 3 or 4, y =1 or 2 or 3 or 4, the channel i Middle transmission plate x The coupling capacitance between the first shield plate and the first shield plate is defined as C is xU , the channel i Middle transmission plate x The coupling capacitance between the shield plate and the second shield plate is defined as C is xL , the coupling capacitance between the first shielding plate and the second shielding plate is defined as C s UL , will i Channel transmission plate x With the k Channel transmission plate y The cross-coupling capacitance between C ik xy , port i The self-capacitance of 1 is recorded as , The calculation formula is: ; port iThe self-capacitance of 2 is recorded as , The calculation formula is: ; aisle i Port a and channel k The mutual capacitance between port b is recorded as , The calculation formula is: .

[0012] Preferably, the calculation formula for determining the compensation inductance and capacitance connected at both ends of the coupler based on the calculated self-capacitance and mutual capacitance is: ; ; in, Indicates the i The transmitter compensation inductor of each channel, Indicates the i The receiving end compensation inductor of each channel, Indicates the i The mutual capacitance of the coupler for each channel, Indicates the i The coupling coefficient of each channel, Indicates the system angular frequency.

[0013] In general, compared with the prior art, the above technical solution conceived by the present invention is applicable to high-power multi-channel electric field wireless power transmission systems. Due to the upper and lower shielding plates, the coupler has the advantage of reducing electric field radiation. Due to the large self-capacitance, the coupler also has the advantage of reducing compensation inductance. At the same time, the coupler is also conducive to channel expansion for different power requirements. Coupler modeling is a key step in the design of CWPT systems. By equating the coupler to the self-capacitance of the transmitting and receiving ends and the coupling mutual capacitance, the compensation network design can be carried out in a targeted manner to improve the system transmission efficiency. The present invention also proposes an equivalent modeling method that takes into account all coupling capacitances of multi-channel couplers. The calculated self-capacitance and mutual capacitance can be used to carry out system parameter design. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a three-dimensional view of an integrated multi-channel coupler according to an embodiment of the present invention; Figure 2 is a front view of an integrated multi-channel coupler according to an embodiment of the present invention; Figure 3 2. It is a schematic diagram of the dimensions of the front view and the left view of the integrated multi-channel coupler according to an embodiment of the present invention; Figure 4This is the channel of the embodiment of the present invention i Schematic diagram of the coupling capacitors between the four transmission plates and the upper and lower shield plates; Figure 5 This is the channel of the embodiment of the present invention i Four transmission plates and channels k Cross-coupling capacitance between the four transmission plates; Figure 6 is an integrated multi-channel coupler controlled current source model according to an embodiment of the present invention; Figure 7 This is a simplification process of the full capacitance model of the integrated multi-channel coupler according to an embodiment of the present invention; Figure 8 FIG. 4 is an equivalent circuit diagram of a CPT system with SS compensation according to an embodiment of the present invention. DETAILED DESCRIPTION

[0015] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0016] In the description of the embodiments of this application, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly specifying the quantity of the technical features indicated. "Multiple" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0017] The terms "including" and "having" and any variations thereof in the embodiments of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product or device comprising a series of steps or modules is not necessarily limited to those steps or modules explicitly listed, but may include other steps or modules not explicitly listed or inherent to these processes, methods, products or devices.

[0018] The present invention proposes an integrated multi-channel coupler and its modeling and parameter design methods, which are described in detail below.

[0019] An integrated multi-channel coupler according to an embodiment of the present invention, the three-dimensional view, the main view and the dimension view are respectively as follows: Figures 1 to 3 The integrated multi-channel coupler includes n channels, each channel consists of four rectangular transmission plates of the same size. P i1 and P i2The first transmission plate and the second transmission plate of the i-th channel constitute the transmitting end plate group. 1 and 2 represent the plate numbers. P i3 and P i4 The third and fourth transmission plates of the i-th channel constitute the receiving end plate group, and 3 and 4 represent the plate numbers. In addition, the integrated coupler also includes a first shielding plate covering all channels. P U and the second shielding plate P L The transmission plate and shielding plate are both aluminum plates with dimensions of l 3× l 4× t and l 1× l 2× t ,in l 1. l 3 and l 2. l 4 represents the length and width respectively, t Indicates thickness. d 1 represents the distance between the transmission plates, i.e. the transmission distance; d 2 represents the distance between the shielding plate and the transmission plate, i.e., the shielding distance; d 3 represents the spacing distance between adjacent channels; d 4 represents the distance between the two transmitting end plates or the two receiving end plates of each channel.

[0020] The spacing distances between adjacent channels do not have to be equal, but from the perspective of minimizing the volume of the coupler, it is preferred that the spacing distances between adjacent channels be equal. d 1 indicates the transmission distance of the system, which is determined according to the actual application scenario. d 2 represents the shielding distance. From the perspective of increasing transmission power and efficiency, the larger the shielding distance, the better. However, if it is too large, the overall size of the coupler will be too large. Therefore, it is preferably set to d 2 is within 5cm±1cm. d 3 represents the spacing distance between channels. Since there will be cross-coupling between the plates of different channels, it is preferably set to be greater than 5cm. In this way, the cross-coupling capacitance can be reduced to less than 5%, and the impact can be ignored.

[0021] According to the mechanism of capacitance generation, there is coupling capacitance between any two plates in the integrated multi-channel coupler. i For example, the channel i Middle transmission plate x With transmission plate y The coupling capacitance between Ci xy , where the superscript i Indicates the channel number ( i =1,2,3……, n ), subscript x and y Indicates the transmission plate number ( x =1,2,3,4; y =1,2,3,4). i Middle transmission plate x and the first shielding plate P U The coupling capacitance between C is xU , the channel i Middle transmission plate x and the second shielding plate P L The coupling capacitance between C is xL , first shielding plate P U , second shielding plate P L The coupling capacitance between C s UL ,like Figure 4 In addition, there are cross-coupling capacitors between the transmission plates of different channels. i Channel transmission plate x With the k Channel transmission plate y The cross-coupling capacitance between C ik xy , superscript i 、 k Indicates the channel number ( k =1,2,3……, n ), subscript x and y Indicates the transmission plate number, such as Figure 5 As shown in Figure 2, it can be seen that due to the cross-coupling between the transmission plates of different channels, the full capacitance model of the integrated multi-channel coupler includes In order to facilitate the design of system parameters, the present invention simplifies the integrated multi-channel coupler into a simplified model in which each channel only includes the primary self-capacitance, secondary self-capacitance and mutual capacitance.

[0022] The integrated coupler full capacitance model is simplified based on the controlled current source model, and its equivalent controlled current source model is as follows: Figure 6 As shown. The controlled current source model includes n +1 controlled current source, emitter plate P i1 and P i2 Connected to the transmitter circuit to form a port i 1; Receiver plate P i3 and P i4 Connected to the receiving end circuit to form a port i 2, forming port s. i controlled current sources, 1≤ i ≤ n , the transmitting end plate P i1 and P i2 Connected to the transmitter circuit to form a port i 1; Receiver plate P i3 and P i4 Connected to the receiving end circuit to form a port i 2; For the n +1 controlled current source, first shield P U and the second shielding plate P L Composed of ports. Port i The voltage and current of 1 are V i1 , I i1 ,port i2 The voltage and current are V i2 , I i2 , the voltage and current at port s are V 3 and I 3. C i1 and C i2 Respectively represent ports i 1 and port i 2's self-capacitance, C 3 represents the port s of self-capacitance. C Miakb Indicates channel i Port a and channel k Port b In order to simplify the calculation process, the cross-coupling mutual capacitance between PU and P L Port defined as channel 0 s . C Mia0s Indicates channel i Port a and Channel 0 port s The cross-coupling mutual capacitance between them. Indicates channel i Port 1 of channel 1 and port 0 of channel 0 s The cross-coupling mutual capacitance between Indicates channel i Port 2 of channel 0 and port s The cross-coupling mutual capacitance between Indicates the port of channel 0 s and channel k Port a The cross-coupling mutual capacitance between a , b Indicates the port number, that is a , b is equal to 1 or 2. The relationship between the above variables can be expressed as formula (1), and the controlled current source of each port can be calculated as formula (2).

[0023] (1); (2); in, ω =2 πf , f represents the switching frequency, Indicates the size of the controlled current source at port i1, Indicates the size of the controlled current source at port i2, represents the size of the controlled current source of port s, j represents the reset unit, ω represents the system angular frequency, and k also represents the channel number. According to the energy conservation theory, it is obvious that C Miakb = C Mkbia , C Mias = C Msia In order to calculate the self-capacitance of each port and the mutual capacitance of each channel, it is necessary to establish the relationship between the integrated multi-channel coupler full capacitance model and the controlled current source model. i 1 self-capacitance C i1 For example, it can be calculated according to formula (3).

[0024] (3); Figure 7 The simplification process of the integrated multi-channel coupler full capacitance model is shown. i 1, the voltage of other ports is 0, so other ports are short-circuited. i3 and P i4 , P k1 and P k2 , P k3 and P k4 When both channels are shorted, any two channels of the integrated multi-channel coupler i and k The full capacitance model between ports is as follows Figure 7 (a). By Figure 7 The parallel capacitor combination in (a) can be obtained Figure 7 (b).

[0025] (4); in, 、 、 、 、 、 、 、 Both represent the combined value of several capacitors connected in parallel.

[0026] When k=0, P U and P L The relevant capacitances can be combined as: (5); in, 、 、 Both represent the combined value of several capacitors connected in parallel.

[0027] definition V Pi1 , V Pi2 , V Pi3 , V Pi4 , V PU and V PL For the plate P i1 , P i2 , P i3 , P i4 , P U and P L The node voltage, represents the node voltage of the kth channel plate a, Represents the combined capacitance. Plate P i2 Set as the reference node, its node voltage is 0. According to KCL, the node current equation can be expressed as (6).

[0028] (6); It should be noted that the fourth equation in (6) indicates that except for the node P i1 , P i2 , P i3 , P i4 The sum of all other node current equations except ka The voltage is: (7); Substituting Equation (7) into the third equation in Equation (6), the node voltage can be calculated V Pi3 (8); Then combine equations (6), (7), and (8) to calculate the port i 1 self-capacitance C i1 for: (9); When the transmitting and receiving ends of the coupler are symmetrical, C i 13 = C i 24 , C i 14 = C i 23 , C ik 11 = C ik 22 , C ik 12 = C ik 21 , C ik 13 = C ik 24 and C ik 14 = Cik 23 , therefore, formula (9) can be further simplified to (10) (10); Similarly, we can also define V 11 = V 12 = … = V n1 = V n2 = V 3=0 and V i2 ≠0, calculation port i 2 self-capacitance C i2 ;definition V 11 = V 12 = … = V n1 = V n2 = V 3=0 and V i1 ≠0, calculation channel i Mutual capacitance C Mi1i2 .

[0029] (11); (12); The technical solution of the present invention proposes an integrated multi-channel coupler and a modeling method thereof. The coupler can be applied to a high-power multi-channel electric field wireless power transmission system. Due to the presence of two upper and lower shielding plates, the coupler has the advantages of reducing electric field radiation and reducing compensation inductance, and is also conducive to channel expansion. In view of the problem that the coupler has a large number of coupling capacitors and the equivalent modeling is complex, an equivalent modeling method considering all coupling capacitors of the coupler is proposed based on a controlled current source model. The calculated self-capacitance and mutual capacitance can be used to carry out system parameter design. In order to improve the energy transmission efficiency of the CPT system, it is necessary to connect compensation inductors and capacitors at both ends of the coupler to resonate with the capacitance of the coupler itself, thereby eliminating reactive power in the system transmission process and improving transmission efficiency.

[0030] The parameter design of the integrated multi-channel coupler system includes the following steps: (1) A controlled current source model is established for the integrated multi-channel coupler. The controlled current source model is as described above. Self-capacitance and mutual capacitance are calculated based on the controlled current source model.

[0031] (2) Determine the compensation inductance and capacitance connected at both ends of the coupler based on the calculated self-capacitance and mutual capacitance.

[0032] ; ; in, Indicates the i The transmitter compensation inductor of each channel, Indicates the i The receiving end compensation inductor of each channel, Indicates the i The mutual capacitance of the coupler for each channel, Indicates the i The coupling coefficient of each channel, Indicates the system angular frequency.

[0033] Taking typical SS compensation as an example, its equivalent circuit diagram is as follows Figure 8 As shown, the coupler is equivalent to a π-type circuit, and the calculated value according to the model established by the present invention is C i1 、 C i2 and C Mi , we can get the self-capacitance and mutual capacitance in the π-type circuit as C i1 - C Mi 、 C i2 - C Mi and C Mi .

[0034] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0035] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An integrated multi-channel coupler, characterized in that: include: n channels arranged side by side, n ≥2, each channel includes a transmitting end plate group and a receiving end plate group, the transmitting end plate group includes a first transmission plate and a second transmission plate, the receiving end plate group includes a third transmission plate and a fourth transmission plate, the first transmission plate and the third transmission plate are arranged in a positive coupling arrangement, and the second transmission plate and the fourth transmission plate are arranged in a positive coupling arrangement; The first shielding plate and the second shielding plate can cover all channels. The first shielding plate is located outside the transmitting end plate group away from the receiving end plate group, and the second shielding plate is located outside the receiving end plate group away from the transmitting end plate group.

2. The integrated multi-channel coupler according to claim 1, wherein: The first transmission plate, the second transmission plate, the third transmission plate, and the fourth transmission plate are all rectangular aluminum plates with the same size.

3. The integrated multi-channel coupler according to claim 1, wherein: The distances between adjacent channels are equal.

4. The modeling method of an integrated multi-channel coupler according to any one of claims 1 to 3, characterized in that: A controlled current source model is established for the integrated multi-channel coupler, wherein the controlled current source model includes n +1 controlled current source, and the first transmission plate is denoted as P i1 , the second transmission plate is marked as P i2 , the third transmission plate is marked as P i3 , the fourth transmission plate is recorded as P i4 , the first shielding plate is marked as P U , the second shielding plate is marked as P L , for the i controlled current sources, 1≤ i ≤ n , the first transmission plate P i1 , the second transmission plate P i2 Connected to the transmitter circuit to form a port i 1; The third transmission plate P i3 , the fourth transmission plate P i4 Connected to the receiving end circuit to form a port i 2. For the n +1 controlled current source, first shield P U and the second shielding plate P L Composed port s.

5. The modeling method of an integrated multi-channel coupler according to claim 4, characterized in that: The channel i Middle transmission plate x With transmission plate y The coupling capacitance between C i xy , subscript x and y Indicates the transmission plate number, x =1 or 2 or 3 or 4, y =1 or 2 or 3 or 4, the channel i Middle transmission plate x The coupling capacitance between the first shield plate and the first shield plate is defined as C is xU , the channel i Middle transmission plate x The coupling capacitance between the shield plate and the second shield plate is defined as C is xL , the coupling capacitance between the first shielding plate and the second shielding plate is defined as C s UL , will i Channel transmission plate x With the k Channel transmission plate y The cross-coupling capacitance between C ik xy , port i The self-capacitance of 1 is recorded as , The calculation formula is: ； port i The self-capacitance of 2 is recorded as , The calculation formula is: ； aisle i Port a and channel k The mutual capacitance between port b is recorded as , The calculation formula is: 。 6. The parameter design method of an integrated multi-channel coupler according to any one of claims 1 to 3, characterized in that: Including steps: A controlled current source model is established for the integrated multi-channel coupler, wherein the controlled current source model includes n +1 controlled current source, and the first transmission plate is denoted as P i1 , the second transmission plate is marked as P i2 , the third transmission plate is marked as P i3 , the fourth transmission plate is recorded as P i4 , the first shielding plate is marked as P U , the second shielding plate is marked as P L , for the i controlled current sources, 1≤ i ≤ n , the first transmission plate P i1 , the second transmission plate P i2 Connected to the transmitter circuit to form a port i 1; The third transmission plate P i3 , the fourth transmission plate P i4 Connected to the receiving end circuit to form a port i 2. For the n +1 controlled current source, first shield P U and the second shielding plate P L Composition port s; Calculate self-capacitance and mutual capacitance based on the controlled current source model; The compensation inductance and capacitance connected at both ends of the coupler are determined based on the calculated self-capacitance and mutual capacitance.

7. The parameter design method of an integrated multi-channel coupler according to claim 6, characterized in that: The channel i Middle transmission plate x With transmission plate y The coupling capacitance between C i xy , subscript x and y Indicates the transmission plate number, x =1 or 2 or 3 or 4, y =1 or 2 or 3 or 4, the channel i Middle transmission plate x The coupling capacitance between the first shield plate and the first shield plate is defined as C is xU , the channel i Middle transmission plate x The coupling capacitance between the shield plate and the second shield plate is defined as C is xL , the coupling capacitance between the first shielding plate and the second shielding plate is defined as C s UL , will i Channel transmission plate x With the k Channel transmission plate y The cross-coupling capacitance between C ik xy , port i The self-capacitance of 1 is recorded as , The calculation formula is: ； port i The self-capacitance of 2 is recorded as , The calculation formula is: ； aisle i Port a and channel k The mutual capacitance between port b is recorded as , The calculation formula is: 。 8. The parameter design method of an integrated multi-channel coupler according to claim 7, characterized in that: The calculation formula for determining the compensation inductance and capacitance connected at both ends of the coupler based on the calculated self-capacitance and mutual capacitance is: ； ； in, Indicates the i The transmitter compensation inductor of each channel, Indicates the i The receiving end compensation inductor of each channel, Indicates the i The mutual capacitance of the coupler for each channel, Indicates the i The coupling coefficient of each channel, Indicates the system angular frequency.

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