A control method and device for realizing constant-current and constant-voltage output of a wireless power transmission system

Abstract

This invention belongs to the field of wireless power transfer technology, specifically relating to a control method and apparatus for achieving constant current and constant voltage output in a wireless power transfer system. The method includes: constructing a wireless power transfer system with high-precision constant current and constant voltage output characteristics based on an LCC-S topology considering parasitic resistance; and controlling the output characteristics by adjusting a high-precision control module in the wireless power transfer system to achieve high-precision constant current and constant voltage output. This invention proposes a convenient high-precision constant current and constant voltage output control method based on the LCC-S topology. This method can simultaneously achieve constant current and constant voltage output using a single topology, and precisely controls the output characteristics by adjusting a high-precision control module without the need for additional circuitry, thereby effectively improving the system's integration and efficiency while ensuring accuracy.

Description

Technical Field

[0001] This invention belongs to the field of wireless power transmission technology, specifically relating to a control method and device for realizing constant current and constant voltage output of a wireless power transmission system. Background Technology

[0002] With the rapid development of wireless power transfer technology, numerous studies are focusing on promoting the practical application of this system. Among these studies, using wireless power transfer technology to charge lithium-ion batteries has become an important research direction. Organically combining wireless power transfer with lithium-ion battery fast charging technology will not only help improve the overall performance of the system but will also further promote the practical application of wireless charging technology in a wider range of fields.

[0003] Constant current and constant voltage charging is a widely used, high-efficiency charging method for lithium batteries. It achieves a balance between charging speed, battery capacity, and safe lifespan, leading to its increasingly widespread application. The constant current and constant voltage charging process consists of two continuous stages: Initially, constant current charging is used, maintaining a constant charging current while the battery voltage gradually increases. This increases the battery's equivalent impedance and consequently, the system's equivalent load. When the battery voltage reaches a preset constant voltage threshold, the charging process automatically switches to constant voltage mode. In this stage, the charging voltage remains constant, while the charging current gradually decreases exponentially according to the battery's saturation state. Simultaneously, the battery's equivalent impedance continues to rise, further increasing the system's equivalent load.

[0004] In academic analysis of constant current and constant voltage output characteristics, the influence of parasitic resistance in the resonant network is often ignored. However, this simplification differs significantly from real-world applications—parasitic resistance objectively exists in actual systems, and its impact on output characteristics cannot be ignored. Furthermore, the constant current and constant voltage charging process itself causes changes in the system's equivalent load; especially when the equivalent load resistance is within a relatively small range of 3Ω to 100Ω, the interference from parasitic resistance is further amplified. This makes it difficult for any existing constant current and constant voltage topology to achieve high-precision constant current or constant voltage output. To address this accuracy issue, engineering practice typically requires the introduction of an additional DC-DC circuit after the rectifier stage to ensure the system's constant current and constant voltage characteristics. However, this approach has two significant drawbacks: firstly, it directly increases the overall system size; secondly, it leads to a decrease in the system's energy conversion efficiency.

[0005] To address this problem, this invention proposes a convenient and high-precision constant current and constant voltage output control method based on the LCC-S topology. This method can achieve constant current and constant voltage output simultaneously using a single topology, and precisely control the output characteristics by adjusting the high-precision control module without the need for additional circuits. This effectively improves the system's integration and efficiency while ensuring accuracy. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a control method and device for realizing constant current and constant voltage output in a wireless power transmission system, aiming to take into account the influence of parasitic resistance and make the wireless power transmission system model closer to actual application scenarios.

[0007] To achieve the above objectives, the present invention provides the following solution: A control method for achieving constant current and constant voltage output in a wireless power transmission system, the method comprising: A wireless power transfer system with high-precision constant current and constant voltage output characteristics is constructed based on the LCC-S topology that takes into account parasitic resistance. By adjusting the output characteristics of the high-precision control module in the wireless power transmission system, high-precision constant current and constant voltage output of the wireless power transmission system can be achieved.

[0008] Preferably, the wireless power transmission system includes: an input DC voltage source, a high-frequency inverter unit, a resonant network, an uncontrolled rectifier unit, and a battery pack, wherein the resonant network includes a transmitting-side resonant network and a receiving-side resonant network; The high-frequency inverter unit consists of MOSFETs S 1~ S A full-bridge inverter consisting of 4 components converts the DC voltage input to the wireless power transmission system into high-frequency AC power. The power transmitter is equipped with internal resistance R Lf1 high-precision control module X Lf1 High-precision control module X Lf1 With internal resistance R 1 transmitting coil L 1. Emitter-side resonant capacitor C Lf1 and C Together, they form a transmitter-side resonant network to achieve the resonant requirements of the wireless power transmission system; On the energy receiving side, including internal resistance R 2 receiving coil L 2. Resonant capacitor on the receiving side C 2. Construct a receiving-side resonant network; The uncontrolled rectifier unit consists of diodes D 1~ D The system consists of an uncontrolled rectifier bridge. AC power is converted to DC by the uncontrolled rectifier unit, and then filtered by a filter capacitor. C r After smoothing and filtering, the battery pack is charged.

[0009] Preferably, for wireless power transmission systems, the high-precision control module in the resonant network is increased.X Lf1 The inductance suppresses fluctuations in the wireless power transfer system under constant current and constant voltage output modes.

[0010] Preferably, in constant current mode, the resonance condition of the wireless power transfer system is: ; in, ω CC It is the operating frequency of a constant current mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1 The inductance value for the high-precision control module. M This refers to the mutual inductance between the transmitting and receiving coils. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

[0011] Preferably, in constant voltage mode, the resonance condition of the wireless power transfer system is: ; in, ω CV It is the operating frequency of a constant voltage mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1 The inductance value for the high-precision control module. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

[0012] The present invention also provides a control device for realizing constant current and constant voltage output of a wireless power transmission system. The device is used to implement the aforementioned method and includes: a system construction module and a control module. The system building module is used to construct a wireless power transfer system with high-precision constant current and constant voltage output characteristics based on the LCC-S topology that takes parasitic resistance into account. The control module is used to control the output characteristics of the wireless power transmission system by adjusting the high-precision control module in the wireless power transmission system, so as to realize the high-precision constant current and constant voltage output of the wireless power transmission system.

[0013] Preferably, the wireless power transmission system includes: an input DC voltage source, a high-frequency inverter unit, a resonant network, an uncontrolled rectifier unit, and a battery pack, wherein the resonant network includes a transmitting-side resonant network and a receiving-side resonant network; The high-frequency inverter unit consists of MOSFETs S 1~ S A full-bridge inverter consisting of 4 components converts the DC voltage input to the wireless power transmission system into high-frequency AC power. The power transmitter is equipped with internal resistance R Lf1 high-precision control module X Lf1 High-precision control module X Lf1 With internal resistance R 1 transmitting coil L 1. Emitter-side resonant capacitor C Lf1 and C Together, they form a transmitter-side resonant network to achieve the resonant requirements of the wireless power transmission system; On the energy receiving side, including internal resistance R 2 receiving coil L 2. Resonant capacitor on the receiving side C 2. Construct a receiving-side resonant network; The uncontrolled rectifier unit consists of diodes D 1~ D The system consists of an uncontrolled rectifier bridge. AC power is converted to DC by the uncontrolled rectifier unit, and then filtered by a filter capacitor. C r After smoothing and filtering, the battery pack is charged.

[0014] Preferably, for wireless power transmission systems, the high-precision control module in the resonant network is increased. X Lf1 The inductance suppresses fluctuations in the wireless power transfer system under constant current and constant voltage output modes.

[0015] Preferably, in constant current mode, the resonance condition of the wireless power transfer system is: ; in, ω CC It is the operating frequency of a constant current mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1 The inductance value for the high-precision control module. MThis refers to the mutual inductance between the transmitting and receiving coils. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

[0016] Preferably, in constant voltage mode, the resonance condition of the wireless power transfer system is: ; in, ω CV It is the operating frequency of a constant voltage mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1 The inductance value for the high-precision control module. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) Simple structure and easy to implement: The innovative control method adopted in this invention does not require the introduction of any additional circuits, which not only simplifies the system architecture and reduces the difficulty of implementation, but also helps to control the complexity of the system, reduce manufacturing costs and achieve lightweight design.

[0018] (2) The system is robust and adaptable: The constructed system model innovatively incorporates the influence of parasitic resistance, making it closer to actual application scenarios. Therefore, no matter how the parasitic parameters fluctuate, the system can maintain high-precision constant current and constant voltage output, demonstrating excellent anti-interference and stability.

[0019] (3) Wide load compatibility and stable performance: Compared with existing technologies, this method can reliably maintain the stability of system output performance over a wider range of load resistance changes, ensuring the reliability and practicality of the system in different application scenarios. Attached Figure Description

[0020] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the wireless power transmission system with constant current and constant voltage output according to an embodiment of the present invention; Figure 2This is a schematic diagram of the equivalent AC circuit for LCC-S type compensation according to an embodiment of the present invention; Figure 3 The diagrams illustrate the effect of parasitic resistance on output under resonant conditions in an embodiment of the present invention. (a) shows the effect when k=0.4 in CV mode, (b) shows the effect when k=0.1 in CV mode, (c) shows the effect when k=0.4 in CC mode, and (d) shows the effect when k=0.1 in CC mode. Figure 4 This is a schematic diagram illustrating the effect of parameter λ on the efficiency of constant voltage and constant current modes in an embodiment of the present invention. Figure 5 This is a schematic diagram of the constant current and constant voltage output fluctuation experiment according to an embodiment of the present invention, wherein (a) is a schematic diagram of current fluctuation rate and (b) is a schematic diagram of voltage fluctuation rate; Figure 6 This is a schematic diagram of the output waveform when k=0.46 in an embodiment of the present invention; Figure 7 This is a schematic diagram of the output waveform when k=0.12 in an embodiment of the present invention; Figure 8 This is a schematic diagram of the constant current and constant voltage mode switching process in an embodiment of the present invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] Example 1 This invention provides a control method for achieving constant current and constant voltage output in a wireless power transmission system, comprising: A wireless power transfer system with high-precision constant current and constant voltage output characteristics is constructed based on the LCC-S topology that takes into account parasitic resistance. By adjusting the output characteristics of the high-precision control module in the wireless power transmission system, high-precision constant current and constant voltage output of the wireless power transmission system can be achieved.

[0025] Figure 1This invention demonstrates the topology of a wireless power transfer system with constant current and constant voltage output characteristics. The wireless power transfer system mainly comprises the following components: an input DC voltage source, a high-frequency inverter unit, a resonant network (including a transmitter-side resonant network and a receiver-side resonant network), an uncontrolled rectifier unit, and a battery pack (which can be equivalent to a variable resistor in circuit analysis).

[0026] This invention incorporates the parasitic resistance of the system into the construction of a wireless power transmission system, thereby seeking a method to enhance the constant current and constant voltage output characteristics of the LCC-S topology, which is closer to actual use scenarios and improves the constant current and constant voltage output characteristics of the LCC-S topology in practical use scenarios.

[0027] The high-frequency inverter unit is composed of MOSFETs. S 1~ S A four-component full-bridge inverter converts the DC voltage input to the wireless power transmission system into the high-frequency AC power required by the system. The power transmitter is equipped with an internal resistance... R Lf1 high-precision control module X Lf1 (capacitance C X1 coil L X2 High-precision control module X Lf1 With transmitting coil L 1 (internal resistance is) R 1) Emitter-side resonant capacitor C Lf1 and C 1. Together, they form the transmitting-side resonant network to achieve the system's resonance requirements. On the energy receiving side, the receiving coil... L 2 (internal resistance is) R 2) Resonant capacitor with the receiving side C 2. This forms the receiving-side resonant network. The uncontrolled rectifier unit consists of diodes. D 1~ D The system consists of an uncontrolled rectifier bridge. AC power is converted to DC by the uncontrolled rectifier unit, and then filtered by a filter capacitor. C r After smoothing and filtering, the battery pack is charged.

[0028] Due to the parasitic resistance of the system R Lf1 , R 1 and RThe presence of parasitic resistance 2 prevents wireless power transfer systems from achieving perfectly ideal constant current and constant voltage output. Therefore, this invention innovatively incorporates the influence of the parasitic resistance mentioned above, making the wireless power transfer system model closer to real-world application scenarios. Based on this, this invention proposes that for wireless power transfer systems with arbitrary coupling coefficients, increasing the high-precision control module in the resonant network... X Lf1 The inductance can effectively suppress system fluctuations in constant current and constant voltage output modes.

[0029] According to the fundamental frequency approximation equivalent method, the effective value of the fundamental frequency voltage U 1 can be represented as: ; in, U in This is the input DC voltage.

[0030] Figure 2 An equivalent AC circuit model for LCC-S type compensation is given, in which... R AC The equivalent resistance of the system is given by the following expression: ; in, R L This is the equivalent load resistance of the battery pack.

[0031] According to Kirchhoff's Voltage Law (KVL), the following equation can be obtained: ; in, j This is the identifier for the imaginary part of a complex number. ω The system's operating angular frequency, X Lf1 The inductance value for the high-precision control module. R Lf1 This represents the parasitic resistance value of the high-precision control module. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. I Lf1 The current value flowing through the high-precision control module. I 1 represents the current flowing through the transmitting coil. L 1 represents the self-inductance of the transmitting coil. R 1 represents the parasitic resistance value of the transmitting coil. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side. R 2 represents the parasitic resistance value of the receiving coil. M This refers to the mutual inductance between the transmitting and receiving coils.I 2 represents the current flowing through the receiving coil. R AC This is the equivalent resistance value.

[0032] In constant current mode, the resonance condition of the system is: ; In constant voltage mode, the resonance condition of the system is: ; in, ω CC and ω CV These are the system operating frequencies for constant current mode and constant voltage mode, respectively.

[0033] Due to the internal resistance of the transmitting coil, receiving coil, and high-precision control module, the constant current and constant voltage output characteristics independent of the load cannot be maintained. Figure 3 Demonstrates different load resistances R L Below, coupling coefficient k Output current gain at values ​​of 0.1 and 0.4 respectively. G IU and output voltage gain G UU The trend of change with system operating frequency. (Comparison) Figure 3 From (a), (b), (c), and (d) in the text, we can conclude that: in different k Value below, R L Will be G IU and G UU This has a significant impact. Therefore, in the LCC-S topology, the constant current and constant voltage output characteristics cannot be fully achieved by setting resonance conditions.

[0034] ; in, k The coupling coefficient is... L 1 represents the self-inductance of the transmitting coil. L 2 represents the self-inductance value of the receiving coil. M This represents the mutual inductance value between the transmitting coil and the receiving coil.

[0035] However, too large X Lf1 This presents two main problems. First, the topology is difficult to implement in practice. Based on the resonance condition of the constant voltage mode, X Lf1 and C Lf1 They are inversely proportional. WhenX Lf1 When emotions are excessive, what is needed C Lf1 The capacitance value will be significantly reduced, possibly falling below the specifications of commercially available capacitors, thus affecting the physical realization of the topology. Secondly, X Lf1 Increased insensitivity can negatively impact the efficiency of the entire system. To quantify this relationship, parameters are defined. λ = X Lf1 / L 1, and in Figure 4 The effect of increasing the voltage on efficiency is shown in constant current and constant voltage modes. Simulation results show that increasing the voltage... X Lf1 The inductance of the material leads to its parasitic resistance. R Lf1 This corresponding increase leads to a greater conduction loss.

[0036] Therefore, as Figure 4 As shown, λ The inductance is maintained within the range of 0.8 to 0.9. This choice not only ensures a sufficiently high inductance value, but also maintains high operating efficiency in both constant current and constant voltage modes, with almost identical performance levels in both modes.

[0037] Figure 5 This demonstrates the coupling coefficient k When the values ​​are 0.12 and 0.46 respectively, the following is adopted: X Lf1 Under three different resonant inductance parameters of 5μH, 30μH, and 70μH, the system... R L The fluctuation rate of output current and voltage during the change from 10Ω to 100Ω; Figures 6-7 Showing k The output waveforms are shown for values ​​of 0.46 and 0.12, respectively. Experimental results indicate that increasing... L f1 The inductance value can effectively suppress fluctuations in the system's output voltage and current.

[0038] Experimental results show that, regardless of the system coupling coefficient, in constant current mode, when the load resistance ( R L When the impedance varies between 3Ω and 10Ω, the output current fluctuation remains within 1%; in constant voltage mode, when R L When the impedance varies between 10Ω and 100Ω, the output voltage fluctuation can also be controlled within 1%. This output characteristic indicates that the system fully meets the requirements of constant current-constant voltage charging applications for lithium batteries.

[0039] This invention proposes that the LCC-S topology can be switched between constant current and constant voltage output modes by adjusting the system operating frequency. The system parameter setting process for both constant current and constant voltage modes is as follows: Figure 8 As shown, the details are as follows: 1. Constant voltage mode parameter design: Based on the system's constant voltage output requirements, first determine the operating angular frequency in constant voltage mode. ω CV Based on the resonance condition of the system in constant voltage mode, the resonant capacitance is obtained. C 1. C 2 and C Lf1 The initial parameter values.

[0040] 2. Parameter tolerance analysis and constant current mode operating angular frequency determination: To ensure the robustness of the system, a resonant capacitor is set. C 1. C 2 and C Lf1 The permissible deviation range for the parameters is 1%. Based on the system's resonance condition in constant current mode, the operating angular frequency that satisfies the constant current mode output is derived. ω CC .

[0041] 3. Iterative optimization process: If there are issues in step 2... ω CC If a feasible solution is found, the parameter design process is complete. If no solution is found, return to step 1 and make minor adjustments to the initial resonant frequency. ω CV Repeat the calculation until a feasible solution that simultaneously satisfies the requirements of constant current mode and constant voltage mode is obtained.

[0042] In summary, this invention proposes a convenient and high-precision constant current and constant voltage output control method based on the LCC-S topology. This method can achieve constant current and constant voltage output simultaneously using a single topology, and precisely control the output characteristics by adjusting the high-precision control module. No additional circuits are required, which effectively improves the system integration and efficiency while ensuring accuracy.

[0043] Example 2 The present invention also provides a control device for realizing constant current and constant voltage output of a wireless power transmission system, for implementing the method described in the foregoing embodiments, the device comprising: a system construction module and a control module; The system building module is used to construct a wireless power transfer system with high-precision constant current and constant voltage output characteristics based on the LCC-S topology that takes parasitic resistance into account. The control module is used to control the output characteristics of the wireless power transmission system by adjusting the high-precision control module in the wireless power transmission system, so as to realize the high-precision constant current and constant voltage output of the wireless power transmission system.

[0044] Furthermore, the wireless power transmission system includes: an input DC voltage source, a high-frequency inverter unit, a resonant network, an uncontrolled rectifier unit, and a battery pack, wherein the resonant network includes a transmitting-side resonant network and a receiving-side resonant network; The high-frequency inverter unit consists of MOSFETs S 1~ S A full-bridge inverter consisting of 4 components converts the DC voltage input to the wireless power transmission system into high-frequency AC power. The power transmitter is equipped with internal resistance R Lf1 high-precision control module X Lf1 High-precision control module X Lf1 With internal resistance R 1 transmitting coil L 1. Emitter-side resonant capacitor C Lf1 and C Together, they form a transmitter-side resonant network to achieve the resonant requirements of the wireless power transmission system; On the energy receiving side, including internal resistance R 2 receiving coil L 2. Resonant capacitor on the receiving side C 2. Construct a receiving-side resonant network; The uncontrolled rectifier unit consists of diodes D 1~ D The system consists of an uncontrolled rectifier bridge. AC power is converted to DC by the uncontrolled rectifier unit, and then filtered by a filter capacitor. C r After smoothing and filtering, the battery pack is charged.

[0045] Furthermore, for wireless power transmission systems, the high-precision control module in the resonant network can be increased. X Lf1 The inductance suppresses fluctuations in the wireless power transfer system under constant current and constant voltage output modes.

[0046] Furthermore, in constant current mode, the resonance condition of the wireless power transfer system is: ; in, ω CC It is the operating frequency of a constant current mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1The inductance value for the high-precision control module. M This refers to the mutual inductance between the transmitting and receiving coils. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

[0047] Furthermore, in constant voltage mode, the resonance condition of the wireless power transfer system is: ; in, ω CV It is the operating frequency of a constant voltage mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1 The inductance value for the high-precision control module. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

[0048] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A control method for achieving constant current and constant voltage output in a wireless power transmission system, characterized in that, The method includes: A wireless power transfer system with high-precision constant current and constant voltage output characteristics is constructed based on the LCC-S topology that takes into account parasitic resistance. By adjusting the output characteristics of the high-precision control module in the wireless power transmission system, high-precision constant current and constant voltage output of the wireless power transmission system can be achieved.

2. The method according to claim 1, characterized in that, The wireless power transmission system includes: an input DC voltage source, a high-frequency inverter unit, a resonant network, an uncontrolled rectifier unit, and a battery pack. The resonant network includes a transmitting-side resonant network and a receiving-side resonant network. The high-frequency inverter unit consists of MOSFETs S 1~ S A full-bridge inverter consisting of 4 components converts the DC voltage input to the wireless power transmission system into high-frequency AC power. The power transmitter is equipped with internal resistance R Lf1 high-precision control module X Lf1 High-precision control module X Lf1 With internal resistance R 1 transmitting coil L 1. Emitter-side resonant capacitor C Lf1 and C Together, they form a transmitter-side resonant network to achieve the resonant requirements of the wireless power transmission system; On the energy receiving side, including internal resistance R 2 receiving coil L 2. Resonant capacitor on the receiving side C 2. Construct a receiving-side resonant network; The uncontrolled rectifier unit consists of diodes D 1~ D The system consists of an uncontrolled rectifier bridge. AC power is converted to DC by the uncontrolled rectifier unit, and then filtered by a filter capacitor. C r After smoothing and filtering, the battery pack is charged.

3. The method according to claim 2, characterized in that, For wireless power transmission systems, increasing the precision control module in the resonant network... X Lf1 The inductance suppresses fluctuations in the wireless power transfer system under constant current and constant voltage output modes.

4. The method according to claim 2, characterized in that, In constant current mode, the resonance condition of the wireless power transfer system is: ； in, ω CC It is the operating frequency of a constant current mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1 The inductance value for the high-precision control module. M This refers to the mutual inductance between the transmitting and receiving coils. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

5. The method according to claim 2, characterized in that, In constant voltage mode, the resonance condition of the wireless power transfer system is: ； in, ω CV It is the operating frequency of a constant voltage mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1 The inductance value for the high-precision control module. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

6. A control device for realizing constant current and constant voltage output in a wireless power transmission system, the device being used to implement the method according to any one of claims 1-5, characterized in that, The device includes: a system construction module and a control module; The system building module is used to construct a wireless power transfer system with high-precision constant current and constant voltage output characteristics based on the LCC-S topology that takes parasitic resistance into account. The control module is used to control the output characteristics of the wireless power transmission system by adjusting the high-precision control module in the wireless power transmission system, so as to realize the high-precision constant current and constant voltage output of the wireless power transmission system.

7. The apparatus according to claim 6, characterized in that, The wireless power transmission system includes: an input DC voltage source, a high-frequency inverter unit, a resonant network, an uncontrolled rectifier unit, and a battery pack. The resonant network includes a transmitting-side resonant network and a receiving-side resonant network. The high-frequency inverter unit consists of MOSFETs S 1~ S A full-bridge inverter consisting of 4 components converts the DC voltage input to the wireless power transmission system into high-frequency AC power. The power transmitter is equipped with internal resistance R Lf1 high-precision control module X Lf1 High-precision control module X Lf1 With internal resistance R 1 transmitting coil L 1. Emitter-side resonant capacitor C Lf1 and C Together, they form a transmitter-side resonant network to achieve the resonant requirements of the wireless power transmission system; On the energy receiving side, including internal resistance R 2 receiving coil L 2. Resonant capacitor on the receiving side C 2. Construct a receiving-side resonant network; The uncontrolled rectifier unit consists of diodes D 1~ D The system consists of an uncontrolled rectifier bridge. AC power is converted to DC by the uncontrolled rectifier unit, and then filtered by a filter capacitor. C r After smoothing and filtering, the battery pack is charged.

8. The apparatus according to claim 7, characterized in that, For wireless power transmission systems, increasing the precision control module in the resonant network... X Lf1 The inductance suppresses fluctuations in the wireless power transfer system under constant current and constant voltage output modes.

9. The apparatus according to claim 7, characterized in that, In constant current mode, the resonance condition of the wireless power transfer system is: ； in, ω CC It is the operating frequency of a constant current mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1 The inductance value for the high-precision control module. M This refers to the mutual inductance between the transmitting and receiving coils. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

10. The apparatus according to claim 7, characterized in that, In constant voltage mode, the resonance condition of the wireless power transfer system is: ； in, ω CV It is the operating frequency of a constant voltage mode wireless power transfer system. L 1 represents the self-inductance of the transmitting coil. C Lf1 and C 1 represents the capacitance value of the emitter-side resonant capacitor. X Lf1 The inductance value for the high-precision control module. L 2 represents the self-inductance value of the receiving coil. C 2 represents the capacitance value of the resonant capacitor on the receiving side.

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