Three-coil wireless power transfer system based on constant-voltage output class-e inverter and design method thereof

Abstract

This invention discloses a three-coil wireless power transfer system and its design method based on a constant-voltage output Class E inverter. The system includes a constant-voltage output Class E inverter that inverts the input DC power and outputs sinusoidal AC power to a three-coil magnetically coupled resonant circuit. The gate of the switching transistor S in the constant-voltage output Class E inverter is connected to a control signal. The source and drain of the switching transistor S are connected through three parallel circuits: the first parallel circuit is connected by a DC-fed inductor L. f With DC voltage V in The series circuit consists of a series connection, and the second parallel circuit consists of a parallel capacitor C. p The third parallel circuit consists of a series capacitor C. s Series inductor L s The circuit consists of three magnetically coupled resonant coils connected in series. Based on the equivalent load on the transmitting side of the three-coil magnetically coupled resonant circuit (rated to the rated load on the receiving side), the parameters of each component in the constant-voltage output Class E inverter are calculated. Finally, simulation verification is performed to adjust the parameters of each component, achieving a constant output voltage under varying load conditions.

Description

Technical Field

[0001] This invention belongs to the field of wireless power transmission and relates to a three-coil wireless power transmission system based on a constant voltage output Class E inverter and its design method. Background Technology

[0002] Wireless Power Transfer (WPT) technology generally refers to a method of power transmission that uses electromagnetic fields as relay energy to transmit electrical energy from the transmitter to the receiver in a contactless manner. Because it avoids the wear and tear and discharge problems caused by frequent plugging and unplugging, wireless power transfer has advantages over traditional wired power transmission methods in terms of convenience, flexibility, and reliability. Magnetic-coupled resonant wireless power transfer is a popular method. Its principle is that the transmitting coil generates a high-frequency magnetic field under the excitation of a high-frequency power supply, and the coupled receiving coil generates current under the influence of this high-frequency magnetic field, thus achieving wireless power transfer. However, due to the high operating frequency of medium-distance wireless power transfer, bridge inverter circuits cannot be adapted to the operating frequency of medium-distance wireless power transfer, making them unsuitable as inverter power supplies for medium-distance wireless power transfer.

[0003] The invention patent with publication number CN108183560A discloses a wireless power transfer system based on a Class E inverter. However, it uses a traditional Class E inverter. The compensation network and closed-loop control can only reduce but not eliminate the switching voltage of the switching transistor when the load changes. Therefore, it cannot achieve a constant output voltage and cannot achieve Class E soft switching. As a result, the voltage and current waveforms of the switching transistor of the Class E inverter overlap when it is turned on and off, resulting in power loss of the switching transistor and a decrease in working efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a three-coil wireless power transfer system and its design method based on a constant-voltage output Class E inverter, in order to solve the problem that existing bridge inverter circuits cannot be used as inverter power supplies for medium-distance wireless power transfer, and the problem that existing wireless power transfer systems based on Class E inverters suffer from reduced efficiency and inability to achieve constant output voltage when the load changes.

[0005] The technical solution adopted in this embodiment of the invention is: a three-coil wireless power transfer system based on a constant voltage output Class E inverter, comprising:

[0006] Low-frequency rectifier and voltage regulator circuit is used to rectify and regulate the mains voltage and output DC voltage;

[0007] A high-frequency inverter circuit is used to invert the DC voltage supplied by a low-frequency rectifier and voltage regulator circuit to output sinusoidal AC power.

[0008] A three-coil magnetically coupled resonant circuit is used for wireless power transmission of sinusoidal alternating current.

[0009] The high-frequency rectifier and voltage regulator circuit is used to rectify and regulate the AC output of the three-coil magnetically coupled resonant circuit, and output DC voltage to the load.

[0010] The high-frequency inverter circuit mentioned above uses a constant voltage output Class E inverter.

[0011] Furthermore, the constant voltage output Class E inverter includes a DC-fed inductor L. f Switch S, parallel capacitor C p Series capacitor C s and series inductor L s ,in:

[0012] The gate of the switching transistor S is connected to a control signal, and the source and drain of the switching transistor S are connected through three parallel loops: the first parallel loop is connected by a DC-fed inductor L. f With DC voltage V in The series circuit consists of a series connection, and the second parallel circuit consists of a parallel capacitor C. p The third parallel circuit consists of a series capacitor C. s Series inductor L s It consists of three magnetically coupled resonant circuits connected in series.

[0013] Furthermore, the series inductor L of the constant voltage output Class E inverter s A transmitting circuit consisting of transmitting coil L1 and first tuning capacitor C1 is connected between the drain of the switching transistor S and the transmitting coil L1. Transmitting coil L1 is coupled in the same direction to relay coil L2. Relay coil L2 and second tuning capacitor C2 form a series circuit. Relay coil L2 is coupled in the same direction to receiving coil L3. Receiving coil L3 is coupled in the same direction to third tuning capacitor C3 and receiving load R. L They form a series circuit.

[0014] Another technical solution adopted in this embodiment of the invention is: the design method of the three-coil wireless power transfer system based on a constant voltage output Class E inverter as described above, which includes the following steps:

[0015] Step S1: Design the parameters of the three-coil magnetically coupled resonant circuit based on the rated load and output voltage of the receiving side, including coil self-inductance, coil mutual inductance, Litz wire diameter used in the coils, and tuning capacitor size;

[0016] Step S2: Based on the parameters of the three-coil magnetically coupled resonant circuit, design the coil size, spatial structure, and winding method;

[0017] Step S3: Equivalently convert the rated load on the receiving side of the three-coil magnetically coupled resonant circuit to the equivalent load R on its transmitting side. eqCalculate the parameters of each component in the circuit of a constant voltage output Class E inverter, including the DC feed inductor L. f Parallel capacitor C p Series capacitor C s Series inductor L s ;

[0018] Step S4: Design a constant voltage output Class E inverter based on the calculated circuit component parameters of the constant voltage output Class E inverter and perform simulation verification. Further adjust the circuit component parameters of the constant voltage output Class E inverter based on the simulation results.

[0019] Furthermore, the specific calculation process for step S3 is as follows:

[0020] First, given the output current angular frequency ω of the switching transistor S in a constant-voltage Class E inverter, the selected quality factor Q and equivalent resistance R... eq According to Q=ω*L s / R eq Obtain the series inductance L s ;

[0021] The DC feed inductance L is determined by the following process. f Parallel capacitor C p Series capacitor C s Size:

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029] in, ω in The input LC filter circuit angular frequency, The input LC filter circuit refers to the series capacitor C in the constant voltage output Class E inverter circuit. s and series inductor L s The circuit consists of a series loop; θ is the phase of the output current of the constant voltage output Class E inverter; p is a given user-defined variable related to the circuit parameters. V inI1 is the input DC voltage, and I1 is the amplitude of the output current of the constant voltage output Class E inverter, I1 = V R / R eq V R For the equivalent load R eq The voltage is the output voltage amplitude of a Class E inverter with constant voltage output at base frequency; L x For the residual inductance, V X The voltage amplitude of the residual reactance of a Class E inverter with constant voltage output at base frequency, where π is pi; v ds (ωt) is the drain-source voltage of the switching transistor S at time t.

[0030] Furthermore, the values ​​of q and θ under different duty cycles D are determined by the following formula:

[0031] πDq+tan[πq(1-D)]=0;

[0032]

[0033] Furthermore, the values ​​of q and θ under different duty cycles D are as follows:

[0034]

[0035]

[0036] The beneficial effects of the embodiments of the present invention are:

[0037] 1. The proposed constant voltage output Class E inverter can achieve high-efficiency transmission even when only the ZVS condition is met, and can also maintain a constant output voltage under load changes. This solves the problem that the existing wireless power transmission system based on Class E inverters has reduced efficiency and cannot maintain a constant output voltage under load changes.

[0038] 2. A constant voltage output Class E inverter is used as the inverter power supply for three-coil wireless power transmission, which solves the problem that bridge inverter circuits cannot be used as inverter power supplies for medium-distance wireless power transmission due to the high operating frequency of medium-distance wireless power transmission. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be 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.

[0040] Figure 1 This is a schematic diagram of a three-coil wireless power transmission system.

[0041] Figure 2 This is a circuit diagram of a constant voltage output Class E inverter.

[0042] Figure 3 This is the circuit diagram of a three-coil wireless power transmission system.

[0043] Figure 4 The output voltage V is the voltage when the load changes. ds Waveform diagram.

[0044] Figure 5 It is the output voltage V of the switching transistor when the load changes. out Waveform diagram.

[0045] Figure 6 It is the equivalent resistance R eq When the resistance is 1, the output voltage V of the switching transistor is 1. out Waveform diagram.

[0046] Figure 7 It is the equivalent resistance R eq When the resistance is 1, the output voltage V of the switching transistor is 1. out The spectrum diagram.

[0047] Figure 8 It is the equivalent resistance R eq When the resistance is 1, the output voltage V of the switching transistor is 1. out The filtered waveform.

[0048] Figure 9 It is the equivalent resistance R eq When the resistance is 1, the output voltage V of the switching transistor is 1. out The filtered spectrum.

[0049] Figure 10 It is the equivalent resistance R eq When the output voltage V of the switching transistor is infinite out Waveform diagram.

[0050] Figure 11 It is the equivalent resistance R eq When the output voltage V of the switching transistor is infinite out The spectrum diagram.

[0051] Figure 12 It is the equivalent resistance R eq When the output voltage V of the switching transistor is infinite out The filtered waveform.

[0052] Figure 13 It is the equivalent resistance R eq When the output voltage V of the switching transistor is infinite out The filtered spectrum. Detailed Implementation

[0053] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0054] Example 1

[0055] A three-coil wireless power transfer system based on a constant-voltage output Class E inverter, such as Figure 1 As shown, it includes:

[0056] Low-frequency rectifier and voltage regulator circuit is used to rectify and regulate the mains voltage and output DC voltage;

[0057] A high-frequency inverter circuit is used to invert the DC voltage supplied by a low-frequency rectifier and voltage regulator circuit to output sinusoidal AC power.

[0058] A three-coil magnetically coupled resonant circuit is used for wireless power transmission of sinusoidal alternating current.

[0059] The high-frequency rectifier and voltage regulator circuit is used to rectify and regulate the AC output of the three-coil magnetically coupled resonant circuit, and output DC voltage to the load.

[0060] in:

[0061] In a three-coil magnetically coupled resonant circuit, the high-frequency magnetic field generated by the transmitting coil induces a current in the relay coil, and the high-frequency magnetic field generated by the current in the relay coil induces a current in the receiving coil, thus completing the three-coil wireless power transmission.

[0062] The high-frequency inverter circuit described uses a constant-voltage output Class E inverter. Based on the constant-voltage output Class E inverter and a three-coil magnetically coupled resonant circuit tuned to the operating frequency, neglecting the coil internal resistance, when the Class E inverter achieves constant-voltage output, the load R... L The voltage on it can also be kept constant.

[0063] The circuit of a constant voltage output Class E inverter is as follows: Figure 2 As shown, it includes a DC-fed inductor L f Switch S, parallel capacitor C p Series capacitor C s and series inductor L s The gate of the switching transistor S is connected to the control signal, and the source and drain of the switching transistor S are connected through three parallel loops: the first parallel loop is connected by the DC-fed inductor L. f With DC voltage V inThe series circuit consists of a series connection, and the second parallel circuit consists of a parallel capacitor C. p The third parallel circuit consists of a series capacitor C. s Series inductor L s It consists of three magnetically coupled resonant circuits connected in series.

[0064] The circuit of a three-coil wireless power transfer system based on a constant-voltage output Class E inverter is as follows: Figure 3 As shown, the series inductor L of the constant voltage output Class E inverter s A transmitting circuit consisting of transmitting coil L1 and first tuning capacitor C1 is connected between the drain of the switching transistor S and the transmitting coil L1. Transmitting coil L1 is coupled in the same direction to relay coil L2. Relay coil L2 and second tuning capacitor C2 form a series circuit. Relay coil L2 is coupled in the same direction to receiving coil L3. Receiving coil L3 is coupled in the same direction to third tuning capacitor C3 and receiving load R. L They form a series circuit.

[0065] Example 2

[0066] This embodiment proposes a design method for a three-coil wireless power transfer system based on a constant-voltage output Class E inverter, including the following steps:

[0067] Step S1: Design the parameters of the three-coil magnetic coupling resonant circuit based on the rated load and output voltage of the receiving side, including coil self-inductance, coil mutual inductance, the diameter of the Litz wire used in the coil and the size of the tuning capacitor. The function of the tuning capacitor is to make the coil work in the resonant state, and the resonant frequency is consistent with the power supply frequency.

[0068] Step S2: Based on the parameters of the three-coil magnetically coupled resonant circuit, design the coil size, spatial structure, and winding method, including coil diameter, number of coil turns, coil turn spacing, and coil spacing;

[0069] Step S3: Equivalently convert the rated load on the receiving side of the three-coil magnetically coupled resonant circuit to the equivalent load R on its transmitting side. eq and voltage V R Calculate the parameters of each component in the circuit of a constant voltage output Class E inverter, including the DC feed inductor L. f Parallel capacitor C p Series capacitor C s Series inductor L s ;

[0070] Step S4: Based on the calculated parameters of each component in the constant voltage output Class E inverter circuit, i.e., the DC feed inductor L... f Parallel capacitor C p Series capacitor C s Series inductor L sDesign a constant-voltage output Class E inverter and perform simulation verification. Based on the simulation results, further adjust the parameters of each component in the circuit of the constant-voltage output Class E inverter. Because the switching transistor S contains a certain parasitic capacitance, the capacitance C of the constant-voltage output Class E inverter needs to be further adjusted based on the simulation results. p Size, and fine-tune L f And C s The size is because the switching transistor used in the simulation is not an ideal model, but a SPICE model that is very close to the actual switching transistor. Its parasitic output capacitance is related to the drain-source voltage and needs to be adjusted manually.

[0071] Step S5: Based on the circuit component parameters of the constant voltage output Class E inverter adjusted after simulation, combined with... Figure 1 To build a three-coil wireless power transfer system based on a constant-voltage output Class E inverter, the wiring of the components in the constant-voltage output Class E inverter circuit should be kept as short as possible during the construction process to reduce stray parameters in the circuit.

[0072] Traditional Class E inverter circuits achieve high efficiency through soft switching using zero-voltage switching (ZVS) and zero-derivative switching (ZDS) conditions. However, typical electrical equipment requires a constant input voltage, and the input power varies between zero and rated power depending on actual needs. Therefore, the equivalent load in the high-frequency inverter circuit is variable. When the load changes, traditional Class E inverters cannot achieve optimal operating conditions, and the output voltage will change. The constant-voltage output Class E inverter used in this invention sacrifices the ZDS condition, achieving high-efficiency transmission even when only the ZVS condition is met. It can also operate under varying load conditions. L To maintain a constant output voltage under varying conditions, step S3 is implemented as follows:

[0073] For example Figure 2 The constant voltage output Class E inverter circuit shown is based on the rated load R on the receiving side of the three-coil magnetically coupled resonant circuit. L Calculate the equivalent resistance R on its transmitting side. eq Assuming that switch S is turned off first and then turned on, then:

[0074]

[0075]

[0076] In the formula, ω in The input LC filter circuit angular frequency is the input LC filter circuit index. Figure 2 The series capacitor C of the constant voltage output Class E inverter circuit showns and series inductor L s The series circuit formed by Z in For the defined DC-fed inductance L f and parallel capacitor C p Relevant variables.

[0077] Calculate the drain-source voltage v of the switching transistor S. ds (ωt), determined by the ZVS condition and the drain-source voltage v of the switching transistor S. ds (ωt), from which we derive:

[0078]

[0079] In the formula, V in q is the DC voltage, and ω is the angular frequency of the input LC filter circuit. in The ratio of the frequency of the output current to the angular frequency ω, i.e. ω is the angular frequency of the output current of the switch S and the constant voltage output Class E inverter; I1 is the amplitude of the output current of the constant voltage output Class E inverter; θ is the phase of the output current of the constant voltage output Class E inverter; D is the duty cycle; and π is pi.

[0080] To achieve constant voltage output, meaning maintaining a constant output voltage despite load changes, according to Ohm's law, the output voltage remains constant regardless of load changes. Therefore, even if the output current I1 of a Class E inverter changes, the circuit must still operate normally. This means the circuit parameters are independent of the magnitude of the output current I1. Thus, the coefficient of the term containing I1 in the equation is zero. Simultaneously, to satisfy the Zero-Voltage-Sensitive-Vertical ...

[0081] πDq+tan[πq(1-D)]=0;

[0082]

[0083] q and θ can then be solved, and the parameters of each component in the constant voltage output Class E inverter circuit can be calculated:

[0084] p is a user-defined variable related to circuit parameters. I1 is the output current amplitude of a constant voltage output Class E inverter, I1 = V R / R eq , will v ds The formula for calculating (ωt) simplifies to expressions containing p under different duty cycles D:

[0085]

[0086] -cos(qωt-2π(1-D)q)-qcos(ωt+θ)(1-cos(2π(1-D)q)))

[0087] The output voltage amplitude V of the constant voltage output Class E inverter at the fundamental frequency is obtained using the trigonometric Fourier transform. R and the voltage amplitude V of the residual reactance X :

[0088]

[0089]

[0090] Given the operating angular frequency ω and p, substitute v ds (ωt) is used to obtain the output voltage amplitude V of the constant voltage output Class E inverter at the base frequency. R and the voltage amplitude V of the residual reactance X ;

[0091] The selected quality factor Q and equivalent resistance R eq According to Q=ω*L s / R eq Obtain the series inductance L s ;

[0092] The DC feed inductance L is determined by the following process. f Parallel capacitor C p Series capacitor C s Size:

[0093]

[0094]

[0095]

[0096]

[0097] Among them, L x This is the remaining inductance.

[0098] The calculated values ​​of q and θ under different duty cycles D are shown in Table 1.

[0099] Table 1. Values ​​of q and θ under different duty cycles D

[0100]

[0101]

[0102] Verification of calculation results:

[0103] The circuit parameters are calculated by selecting the values ​​of q and θ when D = 0.5: L f =0.91uH, C p =16.7nF, C s=4.18nF, L s =6.3uH, R eq = 5.5Ω. Using the above parameters, a constant voltage output Class E inverter circuit is designed to obtain the output voltage V when the load changes. ds Waveform as Figure 4 As shown, Figure 4 The green, blue, red, and blue-green colors represent the equivalent resistance R in that order. eq For rated resistance, twice the rated resistance, five times the rated resistance, and infinity, by... Figure 4 It can be seen that, with load resistance R eq When the resistance is changed to 2 times, 5 times, or when the output is open, the output voltage amplitude remains essentially unchanged. The output voltage V of the switching transistor varies with the load. out Waveform as Figure 5 As shown, Figure 5 Blue, red, blue-green, and purple represent the equivalent resistance R in that order. eq The values ​​are the rated resistance, twice the rated resistance, five times the rated resistance, and infinity, where the equivalent resistance R is... eq When the amplitude is infinite, the waveform differs significantly from the sine wave, but its fundamental amplitude, after bandpass filtering, is consistent with other load conditions. The equivalent resistance R eq When the resistance is 1, the output voltage V of the switching transistor is 1. out The waveform and spectrum are as follows Figures 6-7 As shown, the equivalent resistance R eq When the resistance is 1, the output voltage V of the switching transistor is 1. out The filtered waveform and spectrum are as follows: Figures 8-9 As shown, the equivalent resistance R eq The output voltage V when it is infinite out Waveforms and spectrum diagrams as follows Figures 10-11 As shown, the equivalent resistance R eq The output voltage V when it is infinite out The filtered waveform and spectrum are as follows: Figures 12-13 As shown, when the equivalent resistance R eq When the voltage is too large, causing the waveform to deviate from a standard sine wave, its fundamental frequency component of the output voltage is sufficient to wirelessly transmit power to the receiving side R through a three-coil system. L When power is supplied, the wireless power transmission coil and tuning capacitor act as filters. Figure 4 In this circuit, the voltage is 0 when the switching transistor is turned on. Under varying load resistance, the switching transistor S can maintain the ZVS condition, achieving high-efficiency operation under soft switching.

[0104] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A three-coil wireless power transfer system based on constant-voltage output class-E inverter, characterized by, Comprise: Low-frequency rectification and voltage stabilization circuit for rectifying and stabilizing the grid voltage and outputting DC voltage; High-frequency inverter circuit for inverting the DC voltage delivered by the low-frequency rectification and voltage stabilization circuit and outputting sinusoidal AC power; Three-coil magnetic coupling resonance circuit for wirelessly transmitting the sinusoidal AC power; High-frequency rectification and voltage stabilization circuit for rectifying and stabilizing the AC output of the three-coil magnetic coupling resonance circuit and outputting DC voltage to the load; The high-frequency inverter circuit adopts a constant-voltage output E-type inverter; the constant-voltage output E-type inverter comprises a direct-current feeding inductor L f , a switching tube S, a parallel capacitor C p , a series capacitor C s and a series inductor L s ; Given the output current angular frequency ω of the switch S of the constant-voltage output class-E inverter, the series inductance L s is obtained from the selected quality factor Q and the equivalent resistance R eq according to Q = ω * L s / R eq ​ The direct current feed inductance L is determined by the following procedure f The size of the parallel capacitance C p The size of the series capacitance C s is determined by the following procedure: ； ； ； ； ； ； ； wherein, , is the angular frequency of the input LC filter circuit, , the input LC filter circuit refers to the series capacitor C s and series inductor L s of the constant-voltage output class-E inverter circuit; is the phase of the output current of the constant-voltage output class-E inverter; p is a given custom variable related to the circuit parameters, , V in is the input DC voltage, I1 is the amplitude of the output current of the constant-voltage output class-E inverter, I1=V R / R eq , V R is the voltage of the equivalent load R eq , that is, the amplitude of the output voltage of the constant-voltage output class-E inverter at the fundamental frequency; is the residual inductance, V X is the voltage amplitude of the residual reactance of the constant-voltage output class-E inverter at the fundamental frequency, π is the circular constant; v ds (ωt) is the drain-source voltage of the switch tube S at time t; q and q at different duty cycles D The values are determined by the following calculation formula: ； 。 2. The three-coil wireless power transfer system based on constant-voltage output class-E inverter of claim 1, wherein, The gate of the switch tube S is connected with a control signal, and the source and the drain of the switch tube S are connected through three parallel loops: the first parallel loop is composed of a direct current feeding inductor L f and a direct current voltage V in in series connection, the second parallel loop is composed of a parallel capacitor C p , and the third parallel loop is composed of a series capacitor C s , a series inductor L s and a three-coil magnetic coupling resonant circuit in series connection.

3. The three-coil wireless power transfer system based on constant-voltage output class-E inverter of claim 1, wherein, The series inductance L of the constant voltage output class E inverter s A transmitting loop consisting of a transmitting coil L1 and a first tuning capacitor C1 is connected between the drain of the switch S, the transmitting coil L1 is coupled inductively with a relay coil L2, the relay coil L2 forms a series loop with a second tuning capacitor C2, the relay coil L2 is coupled inductively with a receiving coil L3, the receiving coil L3 is coupled inductively with a third tuning capacitor C3 and a receiving side load R L A series loop is formed.

4. The three-coil wireless power transfer system based on constant- voltage output class-E inverter of claim 1, wherein, q and p under different duty cycles D are respectively 。 5. The design method of a three-coil wireless power transfer system based on a constant-voltage output class-E inverter according to any one of claims 1 to 4, characterized in that, Comprise the following steps: Step S1: Design the parameters of the three-coil magnetic coupling resonance circuit according to the rated load and output voltage of the receiving side, including the coil self-inductance, coil mutual inductance, coil used Litz wire diameter and tuning capacitor size; Step S2: Design the coil size, space structure and winding method according to the parameters of the three-coil magnetic coupling resonance circuit; Step S3: the rated load of the three-coil magnetic coupling resonant circuit receiving side is equivalent to the equivalent load R of its transmitting side eq , the circuit parameters of each component of the constant-voltage output class-E inverter are calculated, including the DC feed inductance L f , the parallel capacitance C p , the series capacitance C s , and the series inductance L s ; Step S4: Design the constant-voltage output E-class inverter according to the calculated circuit component parameters of the constant-voltage output E-class inverter and perform simulation verification, and further adjust the circuit component parameters of the constant-voltage output E-class inverter according to the simulation results.

Images