Dual-channel WPT system based on bilateral current sharing

Abstract

The invention discloses a double-channel WPT system based on bilateral current sharing, and relates to the field of magnetic coupling wireless power transmission, and a direct current voltage source VIN of the system is connected with a double-channel magnetic coupling mechanism through a double-channel half-bridge inverter and a double-channel LCC resonance compensation network; a transmitting end current sharing channel connected with two channels is arranged between the two-channel LCC resonance compensation network and the two-channel magnetic coupling mechanism; the dual-channel magnetic coupling mechanism is connected with the load resistor RL through the dual-channel S compensation network and the dual-channel half-bridge rectifier; a receiving end current sharing channel connected with the two channels is arranged between the two-channel magnetic coupling mechanism and the two-channel S compensation network; and the filter capacitor CO1 and the filter capacitor CO2 are connected in parallel with the two-channel half-bridge rectifier. According to the dual-channel half-bridge inverter, the ZVS soft switching working condition of the dual-channel half-bridge inverter and the dual-channel transmission power balance can be realized while the constant voltage output characteristic of the system is ensured.

Description

Technical Field

[0001] The present application relates to the field of magnetically coupled wireless power transmission, and in particular to a dual-channel WPT system based on bilateral current sharing. Background Art

[0002] The dual-channel wireless power transfer (WPT) system can reduce the voltage and current stress of system power components such as switch devices, magnetic coupling mechanisms, resonant inductors and capacitors in the system, and is widely used to improve the system transmission power capacity. In the dual-channel WPT system, the magnetic coupling mechanism designed with a stacked coil structure has been widely used, which can not only effectively reduce the structural size of the magnetic coupling mechanism, but also improve its power transmission capacity. Generally, the stacked coil structure magnetic coupling mechanism needs to realize the mutual inductance decoupling of the coils for the decoupling design of the system circuit and its output control. Typical decoupling coil structures include DDQ type coil structure, orthogonal DD type coil structure, BP type coil structure, TP type coil structure, etc., which can realize the mutual inductance decoupling between coils within a certain offset range. However, in the case of the offset of the dual-channel magnetic coupling mechanism, the mutual inductance between the sending and receiving coils of different channels is usually inconsistent, resulting in the problem of unbalanced transmission power between channels in the dual-channel WPT system, thereby limiting the improvement of the system's power capacity. Summary of the invention

[0003] The purpose of this application is to provide a dual-channel WPT system based on bilateral current sharing, which can achieve the ZVS soft switching working condition of the dual-channel half-bridge inverter and the transmission power balance of the dual channels while ensuring the constant voltage output characteristics of the system.

[0004] To achieve the above objectives, this application provides the following solutions:

[0005] In a first aspect, the present application provides a dual-channel WPT system based on bilateral current sharing, the dual-channel WPT system based on bilateral current sharing includes: a DC voltage source V IN , dual-channel half-bridge inverter, dual-channel LCC resonant compensation network, dual-channel magnetic coupling mechanism, transmitting end current sharing channel, dual-channel S compensation network, dual-channel half-bridge rectifier, receiving end current sharing channel, filter capacitor C O1 With filter capacitor C O2 and load resistance R L ;

[0006] The DC voltage source V IN The dual-channel half-bridge inverter, the dual-channel LCC resonant compensation network and the dual-channel magnetic coupling mechanism are connected; a dual-channel transmitting end current sharing channel is set between the dual-channel LCC resonant compensation network and the dual-channel magnetic coupling mechanism;

[0007] The dual-channel magnetic coupling mechanism is connected through a dual-channel S compensation network, a dual-channel half-bridge rectifier and a load resistor R L connection; the dual-channel magnetic coupling mechanism and the dual-channel S compensation network are connected by setting a dual-channel receiving end current sharing channel; filter capacitor C O1 And filter capacitor C O2 In parallel with a dual channel half-bridge rectifier.

[0008] Optionally, the dual-channel magnetic coupling mechanism uses two orthogonally placed DD-type coils.

[0009] Optionally, the dual-channel LCC resonant compensation network includes: an inductor L of the first channel FP1 , capacitor C FP1 and capacitor C P1 and the inductor L of the second channel FP2 , capacitor C FP2 and capacitor C P2 ;

[0010] The inductance L FP1 One end of the inductor L is connected to the first output end of the dual-channel half-bridge inverter. FP1 The other end of the capacitor C FP1 One end and capacitor C P1 One end of the capacitor C FP1 The other end of the capacitor C is connected to one end of the transmitting end coil of the first channel in the dual-channel magnetic coupling mechanism; P1 The other end of the coil is connected to the other end of the transmitting end coil of the first channel in the dual-channel magnetic coupling mechanism;

[0011] The inductance L FP2 One end of the inductor L is connected to the second output end of the dual-channel half-bridge inverter. FP2 The other end of the capacitor C FP2 One end and capacitor C P2 One end of the capacitor C FP2 The other end of the capacitor C is connected to one end of the transmitting end coil of the second channel in the dual-channel magnetic coupling mechanism; P2 The other end of is connected to the other end of the transmitting end coil of the second channel in the dual-channel magnetic coupling mechanism.

[0012] Optionally, the dual-channel S compensation network includes a capacitor C of the first channel S1 and the second channel capacitor C S2 .

[0013] Alternatively, using the formula Determine current parameters; the current parameters include: dual-channel half-bridge inverter output current and output current Transmitter coil current in dual-channel magnetic coupling mechanism and coil current The receiving coil current in the dual-channel magnetic coupling mechanism and coil current Dual channel half bridge rectifier input current and input current Transmitter current shares channel current And the receiving end current sharing channel current

[0014] Among them, M 11 and M 22 is the mutual inductance between the coils in the dual-channel magnetic coupling mechanism, and the current Parameter σ and resistance R E They are L T is the inductance of the transmitting coil in the dual-channel magnetic coupling mechanism, L R is the inductance of the receiving coil in the dual-channel magnetic coupling mechanism, j is a complex number, ω is the system angular frequency, π is the circumference of a circle, is the output voltage of the dual-channel half-bridge inverter, L F is the inductance in the dual-channel LCC resonant compensation network.

[0015] Alternatively, using the formula Determine the output impedance angle θ of the dual-channel half-bridge inverter INV ;

[0016] Using the formula Determine the mutual inductance change rate δ M11 and the mutual inductance change rate δ M22 ; Mutual inductance change rate δ M11 and the mutual inductance change rate δ M22 Mutual inductance M 11 and M 22 Mutual inductance M in the case of positive alignment 11-aligned and mutual inductance M 22-aligned The ratio of

[0017] Among them, the parameters Φ, Ψ and Γ are:

[0018]

[0019] Optionally, the dual-channel half-bridge inverter output power P INV1 And the output power P INV2 for:

[0020]

[0021] in, and Dual-channel half-bridge inverter output voltage.

[0022] Optionally, the dual-channel half-bridge rectifier input power P REC1 and input power P REC2 for:

[0023]

[0024] in,

[0025] Optionally, the transmitting coil current in the dual-channel magnetic coupling mechanism and coil current The receiving coil current Coil current Satisfy the following formulas respectively:

[0026]

[0027] Optionally, the transmission power P of the transmitting coil in the dual-channel magnetic coupling mechanism LT1 , transmission power P LT2 And the transmission power P of the transmitting coil LR1 , transmission power P LR2 Respectively expressed as:

[0028]

[0029] Among them, L T1 and L T2 are the inductance of the first channel coil and the second channel coil inductance of the transmitting end in the dual-channel magnetic coupling mechanism, L R1 and L R2 They are respectively the first channel coil inductance and the second channel coil inductance of the receiving end in the dual-channel magnetic coupling mechanism.

[0030] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0031] The present application provides a dual-channel WPT system based on bilateral current sharing. By adding a dual-channel LCC resonant compensation network and a dual-channel S compensation network to the dual-channel WPT system, the original dual-channel WPT system is based on the LCC-S compensation network to obtain a dual-channel current sharing (Dual-Channel Current Sharing, DCCS) WPT topology, so that the present application can achieve dual-channel transmission power balance while ensuring the constant voltage output characteristics of the system, thereby achieving an improvement in the power capacity of the system; and, through the dual-channel LCC resonant compensation network, the output impedance of the dual-channel half-bridge inverter is designed to be weakly inductive, thereby achieving the ZVS soft switching working condition of the dual-channel half-bridge inverter without affecting energy transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 This is a structural diagram of a dual-channel WPT system based on bilateral current sharing in an embodiment of the present application;

[0034] Figure 2 The structure and size diagram of the magnetic coupling mechanism of the DDQ type coil structure;

[0035] Figure 3 The structure and size diagram of the magnetic coupling mechanism of the orthogonal DD coil structure;

[0036] Figure 4 It is a schematic diagram of the variation curve of the mutual inductance and mutual inductance deviation coefficient K of the dual-channel magnetic coupling mechanism with the offset distance;

[0037] Figure 5 This is a schematic diagram of the fundamental wave equivalent circuit of this application;

[0038] Figure 6 K is the voltage gain deviation coefficient G-VV With the load resistance R L Schematic diagram of the change curve;

[0039] Figure 7 is the inverter impedance angle θ under different mutual inductance change rates INV Schematic diagram;

[0040] Figure 8 It is the voltage and current simulation waveform @ alignment condition, without current sharing channel schematic diagram;

[0041] Fig. 9 It is the pressure current simulation waveform @ alignment condition, with a schematic diagram of the current sharing channel;

[0042] Fig.10 This is the voltage and current simulation waveform @Δx=10cm working condition, without current sharing channel schematic diagram;

[0043] Fig.11 The system voltage and current simulation waveform @Δx=10cm working condition, with a schematic diagram of the current sharing channel. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0045] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0046] In an exemplary embodiment, Figure 1 As shown, a dual-channel WPT system based on bilateral current sharing is provided, which includes: a DC voltage source V IN , dual-channel half-bridge inverter, dual-channel LCC resonant compensation network, dual-channel magnetic coupling mechanism, transmitting end current sharing channel, dual-channel S compensation network, dual-channel half-bridge rectifier, receiving end current sharing channel, filter capacitor C O1 With filter capacitor C O2 and load resistance R L ;

[0047] The DC voltage source V IN The dual-channel half-bridge inverter, the dual-channel LCC resonant compensation network and the dual-channel magnetic coupling mechanism are connected; a dual-channel transmitting end current sharing channel is set between the dual-channel LCC resonant compensation network and the dual-channel magnetic coupling mechanism;

[0048] The dual-channel magnetic coupling mechanism is connected through a dual-channel S compensation network, a dual-channel half-bridge rectifier and a load resistor R L connection; the dual-channel magnetic coupling mechanism and the dual-channel S compensation network are connected by setting a dual-channel receiving end current sharing channel; filter capacitor C O1 And filter capacitor C O2 In parallel with a dual channel half-bridge rectifier.

[0049] like Figure 1 As shown, the DC voltage source V IN Provides system input voltage V IN 400V DC .

[0050] MOSFET tubes Q1~Q2 and Q3~Q4 respectively form a dual-channel half-bridge inverter with parallel input.

[0051] Diodes D1-D2 and D3-D4 form dual-channel half-bridge rectifiers respectively.

[0052] The transmitting end of the dual-channel magnetic coupling mechanism uses two orthogonally placed DD-type coils L T1 and L T2 , receiving coil L R1 and L R2 Has a symmetrical structure; M 11 and M 22 The mutual inductance between two coaxially placed DD-type coils on both sides. The two series-connected inductors L PS and capacitor C PS and inductor L SS , capacitor C SS They respectively form current sharing channels at the transmitting and receiving ends, providing paths for the shared current.

[0053] In order to further explain the reason why the present application adopts the DD type coil, the following comparative analysis is performed on the magnetic coupling mechanism of the typical DDQ type coil structure and the orthogonal DD type coil structure under different offset conditions:

[0054] The structure and size diagram of the magnetic coupling mechanism of DDQ type and orthogonal DD type coil structure are shown as follows: Figure 2 and Figure 3 The magnetic coupling mechanism of the two coil structures adopts the same stacking structure, where L T1 and L T2 There are two transmitting coils, L R1 and L R2 There are two receiving coils respectively. The only difference is that the Q-type coil is replaced with an orthogonal DD-type coil. The dimensions of the transmitting and receiving ends of the magnetic coupling mechanism of the two coil structures are both 400*400mm, and the ferrite core is the same size as the magnetic coupling mechanism. All DD-type coils have 8 turns, and the Q-type coils have 9 turns.

[0055] The three-dimensional finite element simulation was performed using COMSOL software to analyze the offset performance of the magnetic coupling mechanism of the dual-channel DDQ coil structure and the orthogonal DD coil structure. T1 and L R1 The mutual inductance is M 11 , coil LT2 and L R2 The mutual inductance is M 22 , based on the mutual inductance simulation results of the two magnetic coupling mechanisms under offset conditions, as shown in Figure 4 shown.

[0056] Figure 4 Parts (a) to (c) of the diagram respectively depict the mutual inductance M of the two magnetic coupling mechanisms when they are offset along the x, y, and z axes. 11 and M 22 When the two magnetic coupling mechanisms are offset along the x and y axes, the mutual inductance M 11 and M 22 With the offset distance, the change trend is gradually reduced, such as Figure 4 Part (a) and Figure 4 As shown in part (b), the reduced mutual inductance value is different. At this time, M 11 ≠M 22 , under this condition, the transmission power of the two channels is unbalanced, and the transmission power of each channel is proportional to the size of the mutual inductance value according to different compensation network topologies. When the two magnetic coupling mechanisms are offset along the z-axis direction, the mutual inductance M 11 and M 22 The variation trend and magnitude with the offset distance are basically consistent, so it can be approximately considered that M 11 =M 22 ,like Figure 4 As shown in part (c), the transmission power of the two channels can naturally reach a balance under the current working condition. In order to more clearly reflect the mutual inductance M 11 and M 22 As the offset distance changes, the mutual inductance deviation coefficient K = M is defined 11 / M 22 The mutual inductance deviation curves of the two magnetic coupling mechanisms when offset along the x, y, and z axes are as follows: Figure 4 As shown in part (d) of .

[0057] Through the above analysis, the mutual inductance of the two channels of the DDQ and orthogonal DD coil structure magnetic coupling mechanisms are usually inconsistent under offset conditions, and the mutual inductance deviation of the DDQ coil structure magnetic coupling mechanism is relatively small, while the DD coil structure magnetic coupling mechanism has better physical structure symmetry, which is more convenient for processing and manufacturing and parameter consistency design in practical applications. Therefore, the orthogonal DD coil structure is used as the magnetic coupling mechanism of the dual-channel WPT system.

[0058] The dual-channel LCC resonant compensation network includes: the inductor L of the first channel FP1 , capacitor C FP1 and capacitor C P1 and the inductor L of the second channel FP2 , capacitor CFP2 and capacitor C P2 ;

[0059] The inductance L FP1 One end of the inductor L is connected to the first output end of the dual-channel half-bridge inverter. FP1 The other end of the capacitor C FP1 One end and capacitor C P1 One end of the capacitor C FP1 The other end of the capacitor C is connected to one end of the transmitting end coil of the first channel in the dual-channel magnetic coupling mechanism; P1 The other end of the coil is connected to the other end of the transmitting end coil of the first channel in the dual-channel magnetic coupling mechanism;

[0060] The inductance L FP2 One end of the inductor L is connected to the second output end of the dual-channel half-bridge inverter. FP2 The other end of the capacitor C FP2 One end and capacitor C P2 One end of the capacitor C FP2 The other end of the capacitor C is connected to one end of the transmitting end coil of the second channel in the dual-channel magnetic coupling mechanism; P2 The other end of is connected to the other end of the transmitting end coil of the second channel in the dual-channel magnetic coupling mechanism.

[0061] The dual-channel S compensation network includes a first channel capacitor C S1 and the second channel capacitor C S2 .

[0062] In order to study this application, the topological structure of this application is converted into Figure 5 The fundamental equivalent circuit under the frequency domain analysis is shown in FIG. 1 , in which all current and voltage variables are represented by fundamental phasors, and the fundamental equivalent circuit representation matrix is:

[0063]

[0064] The dual-channel half-bridge inverter at the transmitting end uses the same control pulse to provide high-frequency AC input for the two transmission channels. Therefore, the output voltage amplitude and phase of the half-bridge inverter of the two channels are the same, which can be expressed as:

[0065]

[0066] Among them, the internal resistance of each component in the system is ignored, and the impedance in the fundamental wave equivalent circuit representation matrix can be expressed as:

[0067]

[0068] When the system operates in a known resonant state, all impedances in the above formulas are 0;

[0069] In order to simplify the system analysis process, the two channels use the same circuit parameters:

[0070]

[0071] Furthermore, using the formula Determine current parameters; the current parameters include: dual-channel half-bridge inverter output current and output current Transmitter coil current in dual-channel magnetic coupling mechanism and coil current The receiving coil current in the dual-channel magnetic coupling mechanism and coil current Dual channel half bridge rectifier input current and input current Transmitter current shares channel current And the receiving end current sharing channel current

[0072] Among them, M 11 and M 22 is the mutual inductance between the coils in the dual-channel magnetic coupling mechanism, and the current Parameter σ and resistance R E They are L T is the coil resistance at the transmitting end in the dual-channel magnetic coupling mechanism, L R is the receiving coil resistance in the dual-channel magnetic coupling mechanism, j is a complex number, ω is the system angular frequency, π is the circumference of a circle, is the output voltage of the dual-channel half-bridge inverter, L F is the inductance in the dual-channel LCC resonant compensation network.

[0073] According to the current parameter determination formula, the voltage gain G can be obtained VV for:

[0074]

[0075] The voltage gain G′ of the system when there is no current sharing channel is obtained VV for:

[0076]

[0077] From the above formula, we can see that the voltage gain G′ VVIt is independent of the load, that is, the LCC-S compensation network in this application has a constant voltage output characteristic. In order to compare and analyze the output characteristics of the proposed system, the voltage gain deviation coefficient K of the system with and without the current sharing channel is defined. G-VV for:

[0078]

[0079] According to the system parameters in Table 1 and Figure 4 The variation curve of the mutual inductance of the dual-channel magnetic coupling mechanism with the offset distance. Under different offset distances, the current gain deviation coefficient K is calculated. G-VV With the load resistance R L The change curve of Figure 6 As shown. It can be seen that when the dual-channel magnetic coupling mechanism is aligned, K G-VV The load resistor R L The proposed DCCS WPT system has the same voltage gain with or without the current sharing channel, and has a constant voltage output characteristic that is independent of the load. In addition, due to the offset along the z-axis, there is always M 11 =M 22 , the system also has a constant voltage output characteristic that is independent of the load in the case of current sharing channels or not. When the dual-channel magnetic coupling mechanism is offset along the x-axis or y-axis direction, since the x-axis or y-axis direction has a similar change trend, the dual-channel magnetic coupling mechanism is selected here to be offset by 5cm and 10cm along the x-axis direction for analysis. It can be seen that K G-VV Within the maximum offset distance range designed for the system, it is only reduced by 0.18%, which shows that under offset conditions, the proposed DCCS WPT system still maintains a load-independent approximate constant voltage output characteristic.

[0080] Table 1

[0081]

[0082]

[0083] According to the current parameter determination formula, the output impedance of the half-bridge inverter of the two channels is equal, that is, the output impedance Z of the dual-channel half-bridge inverter INV for:

[0084]

[0085] Dual-channel half-bridge inverter output impedance angle θ INV It can be expressed as:

[0086]

[0087] Among them, the parameters Φ, Ψ and Γ are:

[0088]

[0089] In order to analyze the variation of the impedance angle of the dual-channel half-bridge with the mutual inductance of the two channels, the mutual inductance variation rate δ is defined as M11 and δ M22 is the mutual inductance M of the two channels 11 and M 22 Mutual inductance M 11-aligned and M 22-aligned Ratio of:

[0090]

[0091] According to the system parameters shown in Table 1, under different mutual inductance change rates, the dual-channel half-bridge output impedance angle θ is calculated. INV like Figure 7 As shown. Figure 7 As shown, in the case of positive alignment, due to δ M11 =δ M22 , dual-channel half-bridge inverter output impedance angle θ INV is 0, the dual-channel half-bridge inverter can achieve ZPA operation. In addition, when the magnetic coupling mechanism is offset along the z-axis direction, it can be obtained that M11 =δ M22 ,θ INV is 0. During the displacement of the magnetic coupling mechanism along the x or y axis, δ M11 With δ M22 The difference between them gradually increases, θ INV Gradually increases with the offset distance. During the entire migration process, θ INV are all very small negative values. Even when the magnetic coupling mechanism is at the maximum offset position, θ INV It is only -2.5°, at this time, the output impedance of the dual-channel half-bridge inverter is weakly capacitive. In order to ensure the ZVS working characteristics of the WPT system, the output impedance of the dual-channel half-bridge inverter is designed to be weakly inductive through the resonance compensation network parameters. Therefore, the system provided by the present application can compensate for the weak capacitive impedance mentioned above, thereby achieving the ZVS working condition of the dual-channel half-bridge inverter without affecting energy transmission.

[0092] Dual-channel half-bridge inverter output power P INV1 And the output power P INV2 for:

[0093]

[0094] in, and Dual-channel half-bridge inverter output voltage.

[0095] Dual channel half bridge rectifier input power P REC1 and input power P REC2 for:

[0096]

[0097] in,

[0098] Transmitter coil current in dual-channel magnetic coupling mechanism and coil current The receiving coil current and coil current Satisfy the following formulas respectively:

[0099]

[0100] According to the calculation formula of current parameters, and So it can be approximately considered and That is, the transmission power P of the transmitting coil in the dual-channel magnetic coupling mechanism LT1 , transmission power P LT2 And the transmission power P of the transmitting coil LR1 , transmission power P LR2 Respectively expressed as:

[0101]

[0102] Among them, L T1 and L T2 are the coil resistance of the first channel and the coil resistance of the second channel at the transmitting end in the dual-channel magnetic coupling mechanism, L R1 and L R2 They are respectively the first channel coil resistance and the second channel coil resistance of the receiving end in the dual-channel magnetic coupling mechanism.

[0103] Therefore, the present application can simultaneously achieve power balance of the half-bridge inverter, the transmitting and receiving end coils, and the half-bridge rectifier between the two channels. Through simulation research, the output voltage and current (V INV1 , V INV2 , I INV1 , I INV2 ), dual-channel half-bridge rectifier input voltage and current (V REC1 , V REC2 , I REC1 , I REC2 ) and the shared channel current (I PS , I SS) waveform.

[0104] When the dual-channel magnetic coupling mechanism is fully aligned (M 11 =M 22 ), with or without current sharing channels, the output voltage and current of the dual-channel half-bridge inverter (V INV1 , V INV2 , I INV1 , I INV2 ), dual-channel half-bridge rectifier input voltage and current (V REC1 , V REC2 , I REC1 , I REC2 ) Waveform Figure 8 and Fig. 9 As shown, the transmission power of the two channels is also balanced at this time, and the shared channel current (I PS , I SS ) is 0.

[0105] When the dual-channel magnetic coupling mechanism is offset by 10 cm along the x-axis (M 11 ≠M 22 ), in the absence of current sharing channels, the transmission power of the two channels is unbalanced, and the transmission power of each channel is proportional to the size of the mutual inductance. The output voltage and current (V INV1 , V INV2 , I INV1 , I INV2 ), rectifier bridge input voltage and current (V REC1 , V REC2 , I REC1 , I REC2 ) Waveform Fig.10 Under the current working condition, by adding the proposed current sharing channel, the transmission power of the two channels is restored to balance, and the output voltage and current (V INV1 , V INV2 , I INV1 , I INV2 ), rectifier bridge input voltage and current (V REC1 , V REC2 , I REC1 , I REC2 ) and the shared channel current (I PS , I SS ) has a waveform such as Fig.11 Therefore, the proposed current sharing channel can ensure the power balance of the two channels when the mutual inductances are inconsistent.

[0106] The dual-channel WPT system based on bilateral current sharing provided by this application can solve the power imbalance problem caused by the inconsistency of mutual inductance between channels in the dual-channel WPT system. The current sharing channel in this application has little effect on the system transmission power, efficiency and other performance indicators. This application can ensure the constant voltage output characteristics of the system while achieving dual-channel transmission power balance.

[0107] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0108] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A dual-channel WPT system based on bilateral current sharing, characterized in that: The dual-channel WPT system based on bilateral current sharing includes: a DC voltage source V IN , dual-channel half-bridge inverter, dual-channel LCC resonant compensation network, dual-channel magnetic coupling mechanism, transmitting end current sharing channel, dual-channel S compensation network, dual-channel half-bridge rectifier, receiving end current sharing channel, filter capacitor C O1 With filter capacitor C O2 and load resistance R L ; The DC voltage source V IN The dual-channel half-bridge inverter, the dual-channel LCC resonant compensation network and the dual-channel magnetic coupling mechanism are connected; a dual-channel transmitting end current sharing channel is set between the dual-channel LCC resonant compensation network and the dual-channel magnetic coupling mechanism; The dual-channel magnetic coupling mechanism is connected through a dual-channel S compensation network, a dual-channel half-bridge rectifier and a load resistor R L Connection; the dual-channel magnetic coupling mechanism and the dual-channel S compensation network are connected by setting a dual-channel receiving end current sharing channel; filter capacitor C O1 And filter capacitor C O2 In parallel with a dual channel half-bridge rectifier.

2. A dual-channel WPT system based on bilateral current sharing according to claim 1, characterized in that: The dual-channel magnetic coupling mechanism adopts two orthogonally placed DD-type coils.

3. A dual-channel WPT system based on bilateral current sharing according to claim 1, characterized in that: The dual-channel LCC resonant compensation network includes: the inductor L of the first channel FP1 , capacitor C FP1 and capacitor C P1 and the inductor L of the second channel FP2 , capacitor C FP2 and capacitor C P2 ; The inductance L FP1 One end of the inductor L is connected to the first output end of the dual-channel half-bridge inverter. FP1 The other end of the capacitor C FP1 One end and capacitor C P1 One end of the capacitor C FP1 The other end of the capacitor C is connected to one end of the transmitting end coil of the first channel in the dual-channel magnetic coupling mechanism; P1 The other end of the coil is connected to the other end of the transmitting end coil of the first channel in the dual-channel magnetic coupling mechanism; The inductance L FP2 One end of the inductor L is connected to the second output end of the dual-channel half-bridge inverter. FP2 The other end of the capacitor C FP2 One end and capacitor C P2 One end of the capacitor C FP2 The other end of the capacitor C is connected to one end of the transmitting end coil of the second channel in the dual-channel magnetic coupling mechanism; P2 The other end of is connected to the other end of the transmitting end coil of the second channel in the dual-channel magnetic coupling mechanism.

4. A dual-channel WPT system based on bilateral current sharing according to claim 1, characterized in that: The dual-channel S compensation network includes a first channel capacitor C S1 and the second channel capacitor C S2 .

5. A dual-channel WPT system based on bilateral current sharing according to any one of claims 1 to 4, characterized in that: Using the formula Determine current parameters; The current parameters include: dual-channel half-bridge inverter output current and output current Transmitter coil current in dual-channel magnetic coupling mechanism and coil current The receiving coil current in the dual-channel magnetic coupling mechanism and coil current Dual-channel half-bridge rectifier input current and input current Transmitter current shares channel current And the receiving end current sharing channel current Among them, M 11 and M 22 is the mutual inductance between the coils in the dual-channel magnetic coupling mechanism, and the current Parameter σ and resistance R E They are L T is the inductance of the transmitting coil in the dual-channel magnetic coupling mechanism, L R is the inductance of the receiving coil in the dual-channel magnetic coupling mechanism, j is a complex number, ω is the system angular frequency, π is the circumference of a circle, is the output voltage of the dual-channel half-bridge inverter, L F is the inductance in the dual-channel LCC resonant compensation network.

6. A dual-channel WPT system based on bilateral current sharing according to claim 5, characterized in that: Using the formula Determine the output impedance angle θ of the dual-channel half-bridge inverter INV ; Using the formula Determine the mutual inductance change rate δ M11 and the mutual inductance change rate δ M22 ; Mutual inductance change rate δ M11 and the mutual inductance change rate δ M22 Mutual inductance M 11 and M 22 Mutual inductance M in the case of positive alignment 11-aligned and mutual inductance M 22-aligned The ratio of Among them, the parameters Φ, Ψ and Γ are:

7. A dual-channel WPT system based on bilateral current sharing according to claim 5, characterized in that: Dual-channel half-bridge inverter output power P INV1 And the output power P INV2 for: in, and Dual-channel half-bridge inverter output voltage.

8. A dual-channel WPT system based on bilateral current sharing according to claim 5, characterized in that: Dual channel half bridge rectifier input power P REC1 and input power P REC2 for: in, 9. A dual-channel WPT system based on bilateral current sharing according to claim 8, characterized in that: Transmitter coil current in dual-channel magnetic coupling mechanism and coil current The receiving coil current Coil current Satisfy the following formulas respectively:

10. A dual-channel WPT system based on bilateral current sharing according to claim 9, characterized in that: The transmission power P of the transmitting coil in the dual-channel magnetic coupling mechanism LT1 , transmission power P LT2 And the transmission power P of the transmitting coil LR1 , transmission power P LR2 Respectively expressed as: Among them, L T1 and L T2 are the inductance of the first channel coil and the second channel coil inductance of the transmitting end in the dual-channel magnetic coupling mechanism, L R1 and L R2 They are respectively the first channel coil inductance and the second channel coil inductance of the receiving end in the dual-channel magnetic coupling mechanism.

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