Multi-gain output wireless electric energy transmission system

Abstract

The utility model relates to the field of wireless power transmission, and provides a multi-gain output wireless power transmission system. The utility model aims to realize three output voltages on a receiving side only by switching a primary side circuit without a complex controller, thereby ensuring that the structure of the receiving side circuit is simple. According to the main scheme, the inverter comprises an inverter module, a secondary compensation module, a rectifier module, a filter module and a controller module, the core is that the inverter module is used for outputting high-frequency alternating-current voltage and is composed of alternating-current switches S1, S2, S3, S4, S5 and S6, different control signals are generated through the controller module, three-path full-bridge output can be formed, and the inverter module is connected with the secondary compensation module through on-off of the alternating-current switches. And the working mode of the system is changed to realize different voltage gains.

Description

Technical Field

[0001] The invention relates to the field of wireless power transmission and provides a wireless power transmission system with multi-gain output. Background Art

[0002] Wireless power transfer technology has received widespread attention in recent years, mainly because it can charge electronic devices without physical connection, providing great convenience and flexibility. Traditional wireless power transfer systems are usually designed with single-gain output, that is, they can only provide a fixed output voltage or power. However, with the increase in the types of electronic devices and the diversification of their functions, the demand for wireless power transfer systems that can provide multiple output voltages or powers is growing.

[0003] Existing multi-gain output wireless power transfer systems usually rely on complex control circuits to achieve switching between different output voltages. These systems usually require the use of microcontrollers or other electronic control units to monitor and control the output voltage, which not only increases the complexity and cost of the system, but also reduces the reliability and energy efficiency of the system.

[0004] The present invention proposes a novel multi-gain output wireless power transmission system, the main innovation of which is to achieve three different output voltages at the receiving end by simplifying the switching mechanism of the side circuit, while avoiding complex control circuits. This design not only simplifies the structure of the receiving end circuit, but also makes the design process of system parameters easier. In addition, the proposed system can maintain high energy efficiency and stability while meeting the condition of constant output voltage. Summary of the invention

[0005] The present invention proposes a wireless power transmission system with multi-gain output, which realizes the switching of three output voltages through simplified circuit structure and parameter design, thereby improving the flexibility and efficiency of the system.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0007] The present invention provides a wireless power transmission system with multi-gain output, comprising the following modules:

[0008] Input power module: provides DC input voltage;

[0009] Inverter module: used to output high-frequency AC voltage, which is powered by AC switch S 1. S 2. S 3. S 4. S 5 and S 6, through the controller module to generate different control signals, three-way full-bridge output can be formed;

[0010] Primary compensation module: used to compensate reactive power, suppress harmonics, and adjust output gain. The controller module controls the inverter to work in different modes and is connected to the primary compensation inductor. , primary compensation inductance , primary compensation capacitor , primary compensation capacitor and primary compensation capacitor Form different electrical pathways;

[0011] Transmitter module: primary coil In generating a high frequency magnetic field, the secondary coil To couple;

[0012] Receiving module: secondary coil With primary coil Coupling, generating induced voltage;

[0013] Secondary compensation module: Secondary compensation capacitor Used to compensate reactive power and suppress harmonics;

[0014] Rectifier module: The compensated AC power is converted into the DC power required by the load end through a full-bridge rectifier.

[0015] Filter module: output filter capacitor Filter out harmonics;

[0016] Load module: resistance load R L Simulate loads in real applications;

[0017] Controller module: By turning the AC switch on and off, the system's operating mode is changed to achieve different voltage gains.

[0018] In the above scheme, the circuit connection relationship includes:

[0019] The positive terminal of the power supply Vin is connected to the switch One port from the switch Starting from the other port of the circuit, the inductor is connected in series ,capacitance ,capacitance ,inductance , the circuit starts from the inductor , connected to the switch Then from The other port is connected to the negative pole of the power supply Vin.

[0020] Lead the switch from the negative pole of Vin Connect to switch With inductor The nodes between

[0021] Lead the switch from the negative pole of Vin Connect to capacitor ,capacitance The nodes between

[0022] Lead the switch from the positive terminal of Vin Connect to switch With inductor The nodes between

[0023] Lead the switch from the positive terminal of Vin Connect to capacitor ,capacitance The nodes between

[0024] In the inductor With capacitor The node connection between , Connect the primary coil , primary coil Connection inductor With capacitor The nodes between.

[0025] The above scheme includes three working modes:

[0026] Working mode I: Controller controls the switch , , and Switching continuously at 85kHz frequency, , Keep disconnected, and points A and B are the inverter inputs;

[0027] Working mode II: Controller controls the switch , , and Switching continuously at 85kHz frequency, , Keep disconnected, points B and C are the input of the inverter;

[0028] Working mode III: Controller controls the switch , , and Switching continuously at 85kHz frequency, , Keep disconnected, points A and C are inverter inputs.

[0029] In the above scheme, in working mode I, the circuit has two stages in one control cycle:

[0030] Phase 1: In t 0- t 1 time range, switch S 1 and S 3 is closed, the other switches are open, and the diode D 1 and D 4 conduction;

[0031] Phase 2: In t 2- t 3 time range, switch S 2 and S 4 is turned on, the other switches are turned off, and the diode D 2 and D 3 conduction; electricity

[0032] In this mode, the voltage gain G V1 , input impedance Z in1 as follows:

[0033] (6).

[0034] In the above scheme, in working mode II, the circuit has two stages in one control cycle:

[0035] Phase 1: In t 0- t 1 time range, switch S 4 and S 6 is closed, the other switches are open, and the diode D 1 and D 4 conduction;

[0036] Phase 2: In t 2- t 3 time range, switch S 3 and S 5 is turned on, the other switches are turned off, and the diode D 2 and D 3 conduction;

[0037] In this mode, the voltage gain G V2 , input impedance Z in2 as follows:

[0038]

[0039] In the above scheme, in working mode III, the circuit has two stages in one control cycle:

[0040] Phase 1: In t 0- t1 time range, switch S 1 and S 6 is closed, the other switches are open, and the diode D 1 and D 4 conduction;

[0041] Phase 2: In t 2- t 3 time range, switch S 2 and S 5 is turned on, the other switches are turned off, and the diode D 2 and D 3 conduction;

[0042] In this mode, the voltage gain G V3 , input impedance Z in3 as follows:

[0043] .

[0044] Because the present invention adopts the above technical means, it has the following beneficial effects:

[0045] The present invention proposes a wireless power transmission system with multi-gain output. Through the innovatively designed circuit structure and control strategy, three output voltages can be realized on the receiving side, simplifying the circuit structure on the receiving side. The system can achieve different voltage outputs by switching the primary side circuit without a complex controller, significantly improving the flexibility and efficiency of the system. At the same time, the system parameter design process is simple and easy, optimizing the system performance and working stability. Compared with the prior art, the system simplifies the control circuit while improving the multi-voltage output capability, enhancing the practicality and economy of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 The circuit structure diagram of the wireless power transmission system with three voltage outputs;

[0047] Figure 2 This is the timing diagram for mode I;

[0048] Figure 3 is the equivalent circuit diagram of mode I;

[0049] Figure 4 There are two stages of working mode I;

[0050] Figure 5 .It is the timing diagram of working mode II;

[0051] Figure 6 .Equivalent circuit diagram of working mode II;

[0052] Figure 7 There are two stages of working mode II;

[0053] Figure 8 . is the timing diagram of mode III;

[0054] Fig. 9 .Equivalent circuit diagram of mode III;

[0055] Fig.10 There are two stages of working mode III. DETAILED DESCRIPTION

[0056] The following is a detailed description of the embodiments of the present invention. Although the present invention will be described and illustrated in conjunction with some specific embodiments, it should be noted that the present invention is not limited to these embodiments. On the contrary, modifications or equivalent substitutions made to the present invention should all be included in the scope of the claims of the present invention.

[0057] In addition, in order to better illustrate the present invention, numerous specific details are given in the following specific embodiments. It will be understood by those skilled in the art that the present invention can also be implemented without these specific details.

[0058] The three voltage output wireless power transfer systems proposed are as follows: Figure 1 shown. V in is the DC input voltage. L f1 , L f2 , C f1 and C f2 Constitutes primary compensation. L P and L S are the self-inductances of the primary and secondary coils respectively. C P and C S is the series resonant capacitor. M is the mutual inductance between the transmitting coil and the receiving coil. D 1- D 4 constitutes a full-bridge rectifier, C O is the output filter capacitor. R L is a resistive load. R f1 and R f2 yes L C The internal resistance of the resonant circuit inductor, R P and R Sis the internal resistance of the transmitting coil and the receiving coil.

[0059] exist Figure 1 middle, S 1- S 6 is an AC switch composed of a MOSFET and a diode in reverse series to prevent the resonant current from flowing back to the power supply from the MOSFET body diode and affecting the operation of the system. Through the specific combination of six AC switches, three operating modes of the system can be achieved.

[0060] Working mode I: Controller controls the switch , , and Switching continuously at 85kHz frequency, , Keep disconnected, the control timing diagram is as shown in the attached figure Figure 2 As shown, at this time, point A and point B are the inverter input;

[0061] Working mode II: Controller controls the switch , , and Switching continuously at 85kHz frequency, , Keep disconnected, the control timing diagram is as shown in the attached figure Figure 5 As shown, points B and C are the inputs of the inverter;

[0062] Working mode III: Controller controls the switch , , and Switching continuously at 85kHz frequency, , Keep disconnected, the control timing diagram is as shown in the attached figure Figure 8 As shown, points A and C are the inverter inputs;

[0063] The component parameters satisfy the following equations:

[0064] (1)

[0065] Working Mode I

[0066] When the circuit works as Figure 2 When shown, the equivalent circuit is as follows Figure 3 As shown in Figure 1, there are two working stages in one working cycle of the circuit.

[0067] like Figure 4 Two phases of operating mode I are shown:

[0068] Phase 1t 0- t 1): Switch S 1 and S 3 is closed, the other switches are open, and the diode D 1 and D 4 is turned on. The current loop in the circuit is as follows Figure 4 (a) shown.

[0069] Phase 2 t 2- t 3): Switch S 2 and S 4 is turned on, the other switches are turned off, and the diode D 2 and D 3 is turned on. The current loop in the circuit is as follows Figure 4 (c) shown.

[0070] The circuit steady state of working mode I is analyzed by fundamental wave analysis method. The voltage and current on the AC side and the voltage and current on the DC side should satisfy:

[0071] (2)

[0072] in, represents the DC input voltage on the primary side, represents the effective value of the inverter output AC voltage, represents the DC output voltage on the secondary side, represents the effective value of the rectifier input AC voltage, represents the receiving coil current, Represents the DC output current.

[0073] According to (2), the AC equivalent load and DC load The relationship between them is:

[0074] (3)

[0075] Represents the DC resistive load of the system.

[0076] The circuit needs to satisfy equation (1) to achieve constant voltage output and zero phase angle. The circuit elements need to satisfy

[0077] (4)

[0078] Solving equation (4), the three loop currents in the circuit can be expressed as:

[0079] (5)

[0080] Voltage gain GV1 Represents the ratio between output and input voltage, Z in1 represents the system input impedance. By solving equations (2) and (5), we can obtain G V1 and Z in1 , as shown in formula (6).

[0081] (6)

[0082] Voltage Gain and input impedance The calculation of is of great significance for wireless power transmission systems:

[0083] 1. Voltage gain It reflects the ratio between the output voltage and input voltage of the system in mode I and is an important indicator for evaluating the output capacity of the system. It determines whether the system can provide enough voltage to drive the load, so it is necessary to ensure sufficient voltage gain in system design to meet the load requirements.

[0084] 2. Input impedance refers to the equivalent impedance of the input end of the system in mode I. The size of the input impedance will affect the input matching of the system. A well-matched system can reduce reflection and improve system transmission efficiency. Therefore, in system design, it is necessary to optimize the input impedance to ensure stable operation of the system.

[0085] 3. The parameter solution of voltage gain and input impedance is one of the key steps in the design of wireless power transmission system. Through them, the working performance of the system in different modes can be evaluated. In addition, they also provide important design guidance, which helps to guide the subsequent circuit parameter design and system optimization.

[0086] Therefore, the voltage gain and input impedance The solution of is an important link to ensure the working performance of the wireless power transmission system, and it has important guiding significance for system design.

[0087] Working Mode II

[0088] When the switching sequence of the circuit is Figure 5 As shown, the circuit is in working mode II, and its equivalent AC circuit model is as follows: Figure 6 shown.

[0089] The circuit topology of Mode II is similar to that of Mode I, except that the voltage gain G V2 and input impedance Z in2 It can be expressed as:

[0090] (7)

[0091] like Figure 7 The two phases of working mode II are shown:

[0092] Phase 1 t 0- t 1): Switch S 4 and S 6 is closed, the other switches are open, and the diode D 1 and D 4 is turned on. The current loop in the circuit is as follows Figure 7 (a) shown.

[0093] Phase 2 t 2- t 3): Switch S 3 and S 5 is turned on, the other switches are turned off, and the diode D 2 and D 3 is turned on. The current loop in the circuit is as follows Figure 7 (c) shown.

[0094] Working Mode III

[0095] When the switching sequence of the circuit is Figure 8 As shown, the circuit is in working mode III, and its equivalent AC circuit model is as follows: Fig. 9 shown.

[0096] Circuit Voltage Gain G V3 and system input impedance Z in3 It can be expressed as:

[0097] (8)

[0098] like Fig.10 As shown, in working mode III, the circuit has two stages in one control cycle:

[0099] Phase 1 t 0- t 1): Switch S 1 and S 6 is closed, the other switches are open, and the diode D 1 and D 4 is turned on. The current loop in the circuit is as follows Fig.10 (a) shown.

[0100] Phase 2 t 2- t 3): Switch S 2 and S5 is turned on, the other switches are turned off, and the diode D 2 and D 3 is turned on. The current loop in the circuit is as follows Fig.10 (c) shown.

[0101] System parameter design

[0102] First, the system input voltage, output voltage and system operating frequency are determined by the actual working requirements. Then the coupling mechanism electrical parameters, coil size parameters and coil shape can be continuously optimized to see if they meet the circuit requirements.

[0103] According to (1), the capacitance C f1 and C f2 It can be obtained through formula (9):

[0104] (9)

[0105] Then substitute (9) into (1), and we can get the inductance L f1 and L f2 expression:

[0106] (10)

[0107] Finally, according to (1), the capacitance can be obtained through (11) C p and C s :

[0108] (11)

Claims

1. A wireless power transmission system with multiple gain outputs, characterized in that: Includes the following modules: Input power module: provides DC input voltage; Inverter module: used to output high-frequency AC voltage, which is powered by AC switch S 1. S 2. S 3. S 4. S 5 and S 6, through the controller module to generate different control signals, three-way full-bridge output can be formed; Primary compensation module: used to compensate reactive power, suppress harmonics, and adjust output gain. The controller module controls the inverter to work in different modes and is connected to the primary compensation inductor. , primary compensation inductor , primary compensation capacitor , primary compensation capacitor and primary compensation capacitor Form different electrical pathways; Transmitter module: primary coil In generating a high frequency magnetic field, the secondary coil To couple; Receiving module: secondary coil With primary coil Coupling, generating induced voltage; Secondary compensation module: Secondary compensation capacitor Used to compensate reactive power and suppress harmonics; Rectifier module: converts the compensated AC output into the DC required by the load end through a full-bridge rectifier; Filter module: output filter capacitor Filter out harmonics; Load module: resistance load R L Simulate loads in real applications; Controller module: By turning the AC switch on and off, the system's operating mode is changed to achieve different voltage gains.

2. A wireless power transmission system with multiple gain outputs according to claim 1, characterized in that: The circuit connection relationship includes: The positive terminal of the power supply Vin is connected to the switch One port from the switch Starting from the other port of the circuit, the inductor is connected in series ,capacitance ,capacitance ,inductance , the circuit starts from the inductor , connected to the switch Then from The other port is connected to the negative pole of the power supply Vin. Lead the switch from the negative pole of Vin Connect to switch With inductor The nodes between Lead the switch from the negative pole of Vin Connect to capacitor ,capacitance The nodes between Lead the switch from the positive terminal of Vin Connect to switch With inductor The nodes between Lead the switch from the positive terminal of Vin Connect to capacitor ,capacitance The nodes between In the inductor With capacitor The node connection between , Connect the primary coil , primary coil Connection inductor With capacitor The nodes between.

3. A wireless power transmission system with multiple gain outputs according to claim 2, characterized in that: There are three working modes: Working mode I: Controller controls the switch , , and Switching continuously at 85kHz frequency, , Keep disconnected, and points A and B are the inverter inputs; Working mode II: Controller controls the switch , , and Switching continuously at 85kHz frequency, , Keep disconnected, points B and C are the input of the inverter; Working mode III: Controller controls the switch , , and Switching continuously at 85kHz frequency, , Keep disconnected, points A and C are inverter inputs.

4. A wireless power transmission system with multiple gain outputs according to claim 3, characterized in that: In working mode I, the circuit has two stages in one control cycle: Phase 1: In t 0- t 1 time range, switch S 1 and S 3 is closed, the other switches are open, and the diode D 1 and D 4 conduction; Phase 2: In t 2- t 3 time range, switch S 2 and S 4 is turned on, the other switches are turned off, and the diode D 2 and D 3 conduction; electricity In this mode, the voltage gain G V1 , input impedance Z in1 as follows: （6）。 5. The wireless power transmission system with multiple gain outputs according to claim 3, characterized in that: In working mode II, the circuit has two stages in one control cycle: Phase 1: In t 0- t 1 time range, switch S 4 and S 6 is closed, the other switches are open, and the diode D 1 and D 4 conduction; Phase 2: In t 2- t 3 time range, switch S 3 and S 5 is turned on, the other switches are turned off, and the diode D 2 and D 3 conduction; In this mode, the voltage gain G V2 , input impedance Z in2 as follows: 。 6. The wireless power transmission system with multiple gain outputs according to claim 3, characterized in that: In working mode III, the circuit has two stages in one control cycle: Phase 1: In t 0- t 1 time range, switch S 1 and S 6 is closed, the other switches are open, and the diode D 1 and D 4 conduction; Phase 2: In t 2- t 3 time range, switch S 2 and S 5 is turned on, the other switches are turned off, and the diode D 2 and D 3 conduction; In this mode, the voltage gain G V3 , input impedance Z in3 as follows: 。

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