Parameter identification method for four-pole-plate underwater electric field type wireless power transmission system

Abstract

The invention discloses a parameter identification method for a four-pole-plate underwater electric field type wireless power transmission system. A direct-current power supply, a high-frequency inverter, a transmitting pole plate module, a receiving pole plate module, a system load and a sampling and control module are included. When the system normally transmits electric energy, the system works in a resonant state, input impedance of the system under different loads is calculated by adjusting load impedance and collecting information of voltage and current of an output end of an inverter, and parameters between polar plates of the system are solved by using an equation. Parameter identification can be achieved by collecting the voltage and the current of the output end of the inverter, complex circuits do not need to be added, the driving frequency of the system does not need to be changed, the steps are simple, and various parameters between system polar plates under the seawater medium working condition can be effectively identified.

Description

Technical Field

[0001] The invention relates to the field of wireless power transmission, and in particular to a parameter identification method for a quadrupole underwater electric field type wireless power transmission system. Background Art

[0002] Compared with traditional wired charging methods, wireless charging technology has advantages such as charging safety, reliability, and flexibility, and is particularly suitable for harsh electrical environments such as coal mines and underwater. Compared with magnetically coupled resonant wireless power transmission systems, electric field coupled wireless power transmission systems are lower in cost and more suitable for large-scale deployment in the vast ocean. Moreover, electric field coupled wireless power transmission systems are not troubled by eddy current problems in underwater environments, which can significantly improve system transmission efficiency and stability.

[0003] Autonomous underwater vehicles play an important role in the civil and military fields. Autonomous underwater vehicles are unmanned devices that sail underwater and have the advantages of autonomous control, more flexible offshore operations, and strong concealment. When an autonomous underwater vehicle is performing underwater wireless charging, the position of the autonomous underwater vehicle docked on the charging platform is misaligned due to the impact of seawater fluctuations, resulting in the inability to determine the resistance value between the system plates, affecting the charging efficiency and power, and reducing the service life of the autonomous underwater vehicle battery. Therefore, it is very important to identify the resistance value between the system plates. Summary of the invention

[0004] In order to make up for the deficiencies of the prior art, the embodiment of the present application proposes a parameter identification method for a quadrupole plate underwater electric field type wireless power transmission system to solve the problems existing in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A method for identifying parameters of a quadrupole underwater electric field type wireless power transmission system comprises the following steps:

[0007] Step 1, construct a circuit topology diagram of a quadrupole wireless power transmission system, the circuit topology diagram specifically includes: a DC power supply, a high-frequency inverter, an emitter plate module, a seawater equivalent impedance circuit, a receiving plate module, a system load and a sampling and control module, the DC power supply is connected to the input end of the high-frequency inverter, the output end of the high-frequency inverter is connected to the input end of the emitter plate module, the output end of the emitter plate module is connected to the input end of the seawater equivalent impedance circuit, the output end of the seawater equivalent impedance circuit is directly opposite to the input end of the receiving plate module, the output end of the receiving plate module is connected to the system load, the input port of the sampling and control module is respectively connected to the output end of the high-frequency inverter and the system load, and the output port is connected to the system load; the seawater equivalent impedance circuit is a Π-type equivalent circuit, consisting of an equivalent resistor R Π1, R Π2 , R Π3 The system load is the real load R of the system. F A parallel circuit consisting of an adjustable resistor R used only for parameter identification is controlled by a switch;

[0008] Step 2: Fix the system operating frequency, and obtain the four equivalent capacitances C1, C2, C3 and C4 of the insulating layer according to the size and relative dielectric constant of the plate insulating layer, and calculate their parasitic resistance R C1 , R C2 , R C3 , R C4 , adjust the compensation inductors L1 and L2 according to the capacitance value to make the system work in a resonant state, and calculate its parasitic resistance R L1 , R L2 ;

[0009] Step 3: Connect three system loads with different resistance values ​​respectively, obtain the voltage and current at the output end of the high-frequency inverter, and calculate the corresponding input impedances Z1, Z2 and Z3 of the system respectively;

[0010] Step 4, determine the equivalent circuit of the quadrupole wireless power transmission system when it is in resonance, and obtain a set of equations about the relationship between input impedance, load resistance, parasitic resistance and equivalent resistance in seawater according to Kirchhoff's voltage-current law;

[0011] Step 5: Substitute the input impedance, parasitic resistance and load resistance obtained in steps 2, 3 and 4 into the equations in step 4 to solve for the equivalent resistance R between the plates. Π1 , R Π2 , R Π3 , to achieve parameter identification.

[0012] As a further technical solution of the present invention: the step 2 specifically comprises:

[0013] Step 2.1, through the area S, thickness d and relative dielectric constant ε of the insulating layer on the surface of the plate w ; Calculate the equivalent capacitance of the insulating layer on the surface of each plate

[0014] Where ε0 represents the dielectric constant of vacuum;

[0015] Step 2.2, adjusting the compensation inductors L1 and L2 according to the obtained capacitance value and the system operating frequency, so that the system operates in a resonant state;

[0016] In step 2.3, the parasitic resistance of the capacitor and the compensation inductor are measured using an impedance analyzer.

[0017] As a further technical solution of the present invention: Step 3 specifically includes:

[0018] Step 3.1, the resistance value of the control system load is R1, voltage is applied and the system is judged to be working normally; the voltage U1 and current I1 at the output end of the high-frequency inverter are recorded at this time;

[0019] Step 3.2, the resistance value of the control system load is R2, the voltage is applied and it is judged that the system is working normally; the voltage U2 and current I2 at the output end of the high-frequency inverter are recorded at this time;

[0020] Step 3.3, the resistance value of the control system load is R3, the voltage is applied and it is judged that the system works normally; the voltage U3 and current I3 at the output end of the high-frequency inverter are recorded at this time;

[0021] Step 3.4, calculate the input impedance of the system Z1 = U1 / I1, Z2 = U2 / I2, Z3 = U3 / I3 respectively;

[0022] In the formula, Z1, Z2, and Z3 represent the system input impedance when the system works under three kinds of loads; U1, U2, and U3 represent the high-frequency inverter output terminal voltage when the system works under three kinds of loads; I1, I2, and I3 represent the high-frequency inverter output terminal current when the system works under three kinds of loads.

[0023] As a further technical solution of the present invention: Step 4 specifically includes:

[0024] Step 4.1, simplifying the system circuit into an equivalent circuit when the system is resonant;

[0025] Step 4.2, the equations obtained based on the equivalent circuit at resonance are as follows:

[0026]

[0027] In the formula, a1, a2, a3, b1, b2, and b3 represent intermediate variables.

[0028] As a further technical solution of the present invention: the high-frequency inverter adopts a single-phase full-bridge inverter circuit, and the output voltage is a square wave with a fixed duty cycle, and the output voltage satisfies the formula: Among them U ab is the fundamental effective value of the high frequency inverter output voltage, V DC is the output DC voltage value of the DC power supply.

[0029] As a further technical solution of the present invention: the emitter plate module includes a first plate, a third plate and a first compensation inductor; one end of the compensation inductor is connected to an output end of the high-frequency inverter, and the other end of the compensation inductor is connected to one end of the first plate; the other end of the third plate is connected to another output end of the high-frequency inverter;

[0030] Among them, the inherent resonant frequency of the emitter plate module satisfies the formula: Among them, ω T represents the natural resonant frequency of the emitter plate module, C T Represents the capacitance value of the emitter plate, L T represents the compensating inductance of the emitter plate.

[0031] As a further technical solution of the present invention: the receiving plate module includes a second plate, a fourth plate and a second compensation inductor; one end of the compensation inductor is connected to the input end of the system load, and the other end of the compensation inductor is connected to one end of the second plate; the other end of the fourth plate is connected to the output end of the system load;

[0032] Among them, the natural resonant frequency of the receiving plate module satisfies the formula: Among them, ω S Indicates the natural resonant frequency of the receiving plate module, C S Indicates the capacitance value of the receiving plate, L S Represents the compensation inductance of the receiving plate.

[0033] As a further technical solution of the present invention: the seawater equivalent impedance circuit is composed of six resistors R 12 , R 13 , R 14 , R 23 , R 24 , R 34 Equivalent to three π-type resistors R Π1 , R Π2 , R Π3 ; Among them, the resistor R 12 , R 13 , R 14 , R 23 , R 24 , R 34 are the mutual resistances among the first electrode plate, the second electrode plate, the third electrode plate and the fourth electrode plate.

[0034] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0035] The present invention provides a parameter identification method for a quadrupole underwater electric field type wireless power transmission system based on a variable load. The technology can quickly solve the resistance between the system plates by switching the load resistance. The technology does not need to change the driving frequency of the system, does not need to add complex circuits, has simple steps, and can quickly and accurately achieve parameter identification requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the system structure of the present invention;

[0037] Figure 2 is a detailed circuit topology diagram of the present invention;

[0038] Figure 3 is an equivalent circuit diagram of the system resonant state of the present invention;

[0039] Figure 4 It is a parameter identification flow chart of the present invention;

[0040] Figure 5 A relationship diagram showing the change in the distance between the transmitting and receiving plates of the system of the present invention with respect to the equivalent resistance between the plates;

[0041] Figure 6 The figure is a relationship diagram of the output power and efficiency of the system of the present invention as the distance between the transmitting and receiving plates changes. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] like Figure 1-6 As shown, a method for identifying parameters of a quadrupole underwater electric field type wireless power transmission system based on variable load, the method specifically comprises the following steps:

[0044] Step 1, constructing a circuit topology diagram of a quadrupole wireless power transmission system, wherein the circuit topology specifically includes: a DC power supply 1, a high-frequency inverter 2, a transmitter plate module 3, a seawater equivalent impedance circuit 4, a receiving plate module 5, a system load 6, and a sampling and control module 7;

[0045] Among them, the DC power supply 1 is connected to the input end of the high-frequency inverter 2, the output end of the high-frequency inverter 2 is connected to the input end of the emitter plate module 3, the output end of the emitter plate module 3 is connected to the input end of the seawater equivalent impedance circuit 4, the output end of the seawater equivalent impedance circuit 4 is directly opposite to the input end of the receiving plate module 5, the output end of the receiving plate module 5 is connected to the system load 6, the input port of the sampling and control module 7 is respectively connected to the output end of the high-frequency inverter 2 and the system load 6, and the output port is connected to the system load 6;

[0046] The seawater equivalent impedance circuit 4 is a Π-type equivalent circuit, which consists of an equivalent resistor R Π1 , R Π2 , R Π3 The system load 6 is the real load R of the system FThe parallel circuit composed of the adjustable resistor R used only for parameter identification is controlled by a switch.

[0047] Step 2: Fix the system operating frequency, and obtain the four equivalent capacitances C1, C2, C3 and C4 of the insulating layer according to the size and relative dielectric constant of the plate insulating layer, and calculate their parasitic resistance R C1 , R C2 , R C3 , R C4 , adjust the compensation inductors L1 and L2 according to the capacitance value to make the system work in a resonant state, and calculate its parasitic resistance R L1 , R L2 ; The specific method is as follows:

[0048] Step 2.1, through the area S, thickness d and relative dielectric constant ε of the insulating layer on the surface of the plate w ; Calculate the equivalent capacitance of the insulating layer on the surface of each plate

[0049] Where ε0 represents the dielectric constant of vacuum;

[0050] Step 2.2, adjusting the compensation inductors L1 and L2 according to the obtained capacitance value and the system operating frequency, so that the system operates in a resonant state;

[0051] Step 2.3, using an impedance analyzer to measure the parasitic resistance of the capacitor and the compensation inductor respectively;

[0052] Step 3, respectively connect three system loads 6 with different resistance values, obtain the voltage and current at the output end of the high-frequency inverter 2, and respectively calculate the corresponding input impedances Z1, Z2 and Z3 of the system; the specific method is as follows:

[0053] Step 3.1, the resistance value of the control system load 6 is R1, voltage is applied and it is determined that the system is working normally; the voltage U1 and current I1 at the output end of the high-frequency inverter 2 are recorded at this time;

[0054] Step 3.2, the resistance value of the control system load 6 is R2, the voltage is applied and it is determined that the system is working normally; the voltage U2 and the current I2 at the output end of the high-frequency inverter 2 are recorded at this time;

[0055] Step 3.3, the resistance value of the control system load 6 is R3, the voltage is applied and it is determined that the system is working normally; the voltage U3 and the current I3 at the output end of the high-frequency inverter 2 are recorded at this time;

[0056] Step 3.4, calculate the input impedance of the system Z1 = U1 / I1, Z2 = U2 / I2, Z3 = U3 / I3 respectively;

[0057] In the formula, Z1, Z2, and Z3 represent the system input impedance of the system working under three kinds of loads; U1, U2, and U3 represent the output terminal voltage of the high-frequency inverter 2 of the system working under three kinds of loads; I1, I2, and I3 represent the output terminal current of the high-frequency inverter 2 of the system working under three kinds of loads;

[0058] Step 4, determining the equivalent circuit of the quadrupole wireless power transmission system when it is in resonance, and obtaining a set of equations about the relationship between input impedance, load resistance, parasitic resistance and equivalent resistance in seawater according to Kirchhoff's voltage-current law;

[0059] Step 4.1, when the system resonates, simplify the system circuit to Figure 3 The equivalent circuit of

[0060] Step 4.2, the equations obtained based on the equivalent circuit at resonance are as follows:

[0061]

[0062]

[0063] In the formula, a1, a2, a3, b1, b2, and b3 represent intermediate variables.

[0064] Step 5: Substitute the input impedance, parasitic resistance and load resistance obtained in steps 2, 3 and 4 into the equations in step 4 to solve for the equivalent resistance R between the plates. Π1 , R Π2 , R Π3 , to achieve parameter identification. The specific method is as follows:

[0065] Calculate the parameters in formula 3 according to the system load values ​​R1, R2, and R3, substitute the parameters of formula 3 into formula 2 to calculate the parameters of formula 2, substitute the parameters of formula 2 into formula 1, and calculate the equivalent resistance R in combination with the input impedance values ​​Z1, Z2, and Z3 Π1 , R Π2 , R Π3 .

[0066] Preferably, the high-frequency inverter 2 adopts a single-phase full-bridge inverter circuit, and the output voltage is a square wave with a fixed duty cycle, and the output voltage satisfies the formula: Among them U ab is the fundamental effective value of the high frequency inverter output voltage, V DC is the output DC voltage value of DC power supply 1.

[0067] Preferably, the emitter plate module 3 includes a first plate, a third plate and a first compensation inductor; one end of the compensation inductor is connected to an output end of the high-frequency inverter 2, and the other end of the compensation inductor is connected to one end of the first plate; the other end of the third plate is connected to another output end of the high-frequency inverter 2;

[0068] Among them, the inherent resonant frequency of the emitter plate module satisfies the formula: Among them, ω T represents the natural resonant frequency of the emitter plate module, C T Represents the capacitance value of the emitter plate, L T represents the compensating inductance of the emitter plate.

[0069] Preferably, the receiving plate module 5 includes a second plate, a fourth plate and a second compensation inductor; one end of the compensation inductor is connected to the input end of the system load 6, and the other end of the compensation inductor is connected to one end of the second plate; the other end of the fourth plate is connected to the output end of the system load 6;

[0070] Among them, the natural resonant frequency of the receiving plate module satisfies the formula: Among them, ω S Indicates the natural resonant frequency of the receiving plate module, C S Indicates the receiving plate capacitance, L S Represents the compensation inductance of the receiving plate.

[0071] Preferably, the seawater equivalent impedance circuit 4 consists of six mutual resistors R 12 , R 13 , R 14 , R 23 , R 24 , R 34 Equivalent to three π-type resistors R Π1 , R Π2 , R Π3 ;

[0072] Among them, the resistor R 12 , R 13 , R 14 , R 23 , R 24 , R 34 are the mutual resistances among the first electrode plate, the second electrode plate, the third electrode plate and the fourth electrode plate.

[0073] The following is a specific embodiment of the present invention.

[0074] Step 1, constructing a circuit topology diagram of a quadrupole plate wireless power transmission system;

[0075] refer to Figure 1The circuit topology structure diagram of the quadrupole plate wireless power transmission system shown in the figure, the circuit topology structure specifically includes: a DC power supply 1, a high-frequency inverter 2, a transmitter plate module 3, a seawater equivalent impedance circuit 4, a receiving plate module 5, a system load 6 and a sampling and control module 7;

[0076] The system's DC input voltage V DC The voltage of the system is 100V, the driving frequency of the system is 200kHz, the transmitting plate module and the receiving plate module are both made of aluminum plate, and the insulating material is mica with a dielectric constant of 5.7; the seawater conductivity is set to 4; the R 12 =88.527Ω、R 13 =1.1534Ω、R 14 =95.3198Ω, R 23 =106.3739Ω、R 24 =0.97876Ω, R 34 =114.812Ω, equivalent to π-type resistors R Π1 =2.15486Ω, R Π2 =46.97976Ω, R Π3 =53.4769Ω; three different load resistors are set to R148Ω, R2=50Ω, R3=51Ω;

[0077] Step 2: Fix the system operating frequency, and obtain the four equivalent capacitances C1, C2, C3 and C4 of the insulating layer according to the size and relative dielectric constant of the plate insulating layer, and calculate their parasitic resistance R C1 , R C2 , R C3 , R C4 , adjust the compensation inductors L1 and L2 according to the capacitance value to make the system work in a resonant state, and calculate its parasitic resistance R L1 , R L2 ; The specific method is as follows:

[0078] Step 2.1, the area through the insulating layer on the plate surface S = 25600mm 2 , thickness d = 10 mm and relative dielectric constant ε w =5.7; by formula The equivalent capacitance values ​​of the insulating layer on the surface of each plate are calculated to be C1 = 1.3564nF, C2 = 1.3805nF, C3 = 1.3563nF, and C4 = 1.3804nF;

[0079] Where ε0 represents the dielectric constant of vacuum;

[0080] Step 2.2, according to the obtained capacitance value and the system operating frequency f=200kHz, the compensation inductors L1 and L2 are adjusted to 925.585μH, so that the system works in a resonant state;

[0081] Step 2.3, use an impedance analyzer to measure the parasitic resistance of the capacitor as R C1 =1.125Ω, R C2 =0.959Ω, R C3 =1.1298Ω, R C4 =0.961Ω; Parasitic resistance R of compensation inductor L1 , R L1 Both are 2Ω;

[0082] Step 3, respectively connect three system loads 6 with different resistance values, obtain the voltage and current at the output end of the high-frequency inverter 2, and respectively calculate the corresponding input impedances Z1, Z2 and Z3 of the system; the specific method is as follows:

[0083] Step 3.1, the resistance of the control system load 6 is R1=48Ω, voltage is applied and the system is judged to be working normally; the voltage U1 and current I1 at the output end of the high-frequency inverter 2 are recorded at this time;

[0084] Step 3.2, the resistance of the control system load 6 is R2=50Ω, voltage is applied and the system is judged to be working normally; the voltage U2 and current I2 at the output end of the high-frequency inverter 2 are recorded at this time;

[0085] Step 3.3, the resistance of the control system load 6 is R3=51Ω, voltage is applied and the system is judged to be working normally; the voltage U3 and current I3 at the output end of the high-frequency inverter 2 are recorded at this time;

[0086] Step 3.4, calculate the input impedance of the system Z1 = U1 / I1, Z2 = U2 / I2, Z3 = U3 / I3 respectively;

[0087] In the formula, Z1, Z2, and Z3 represent the system input impedance of the system working under three kinds of loads; U1, U2, and U3 represent the output terminal voltage of the high-frequency inverter 2 of the system working under three kinds of loads; I1, I2, and I3 represent the output terminal current of the high-frequency inverter 2 of the system working under three kinds of loads;

[0088] In this example, the input impedance of the system is calculated to be Z1 = 21.83919Ω, Z2 = 22.032804Ω, and Z3 = 22.12601Ω;

[0089] Step 4, determine the equivalent circuit of the quadrupole wireless power transmission system when it is resonant, and obtain the equation group about the relationship between input impedance, load resistance, parasitic resistance and equivalent resistance in seawater according to Kirchhoff's voltage and current law. The specific method is as follows:

[0090] Step 4.1, when the system resonates, simplify the system circuit to Figure 3 The equivalent circuit of

[0091] Step 4.2, the equations obtained based on the equivalent circuit at resonance are as follows:

[0092]

[0093] In the formula, a1, a2, a3, b1, b2, b3 represent intermediate variables;

[0094] Step 5: Substitute the input impedance, parasitic resistance and load resistance obtained in steps 2, 3 and 4 into the equations in step 4 to solve for the equivalent resistance R between the plates. Π1 , R Π2 , R Π3 , to achieve parameter identification. The specific method is as follows:

[0095] Calculate the parameters a1, a2, and a3 in Formula 3 according to the system load values ​​R1, R2, and R3, substitute the parameters of Formula 3 into Formula 2 to calculate the parameters b1, b2, and b3 of Formula 2, substitute the parameters of Formula 2 into Formula 1, and calculate the equivalent resistance R in combination with the input impedance values ​​Z1, Z2, and Z3 Π1 , R Π2 , R Π3 In this embodiment, R is calculated Π1 =2.131Ω, R Π2 =44.92Ω, R Π3 =56.296Ω, thus achieving parameter identification. Figure 5 , Figure 6 ,By comparing the simulation value with the assumed theoretical value, it can be obtained that the ,error value is small, which fully demonstrates that the method used in the ,presentation is feasible and effective.

[0096] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0097] In addition, it should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment have also been appropriately combined to form other implementation modes that are easy for those skilled in the art to understand.

Claims

1. A method for identifying parameters of a quadrupole underwater electric field wireless power transmission system, characterized in that: The following steps are involved: Step 1, construct a circuit topology diagram of a quadrupole wireless power transmission system, the circuit topology diagram specifically includes: a DC power supply, a high-frequency inverter, an emitter plate module, a seawater equivalent impedance circuit, a receiving plate module, a system load and a sampling and control module, the DC power supply is connected to the input end of the high-frequency inverter, the output end of the high-frequency inverter is connected to the input end of the emitter plate module, the output end of the emitter plate module is connected to the input end of the seawater equivalent impedance circuit, the output end of the seawater equivalent impedance circuit is directly opposite to the input end of the receiving plate module, the output end of the receiving plate module is connected to the system load, the input port of the sampling and control module is respectively connected to the output end of the high-frequency inverter and the system load, and the output port is connected to the system load; the seawater equivalent impedance circuit is a Π-type equivalent circuit, consisting of an equivalent resistor R Π1 , R Π2 , R Π3 The system load is the real load R of the system. F A parallel circuit consisting of an adjustable resistor R used only for parameter identification is controlled by a switch; Step 2: Fix the system operating frequency, and obtain the four equivalent capacitances C1, C2, C3 and C4 of the insulating layer according to the size and relative dielectric constant of the plate insulating layer, and calculate their parasitic resistance R C1 , R C2 , R C3 , R C4 , adjust the compensation inductors L1 and L2 according to the capacitance value to make the system work in a resonant state, and calculate its parasitic resistance R L1 , R L2 ; Step 3: Connect three system loads with different resistance values ​​respectively, obtain the voltage and current at the output end of the high-frequency inverter, and calculate the corresponding input impedances Z1, Z2 and Z3 of the system respectively; Step 4, determine the equivalent circuit of the quadrupole wireless power transmission system when it is in resonance, and obtain a set of equations about the relationship between input impedance, load resistance, parasitic resistance and equivalent resistance in seawater according to Kirchhoff's voltage-current law; Step 5: Substitute the input impedance, parasitic resistance and load resistance obtained in steps 2, 3 and 4 into the equations in step 4 to solve for the equivalent resistance R between the plates. Π1 , R Π2 , R Π3 , to achieve parameter identification.

2. A method for identifying parameters of a quadrupole underwater electric field wireless power transmission system according to claim 1, characterized in that: The step 2 specifically includes: Step 2.1, through the area S, thickness d and relative dielectric constant ε of the insulating layer on the surface of the plate w ; Calculate the equivalent capacitance of the insulating layer on the surface of each plate Where ε0 represents the dielectric constant of vacuum; Step 2.2, adjusting the compensation inductors L1 and L2 according to the obtained capacitance value and the system operating frequency, so that the system operates in a resonant state; In step 2.3, the parasitic resistance of the capacitor and the compensation inductor are measured using an impedance analyzer.

3. The method for identifying parameters of a quadrupole underwater electric field wireless power transmission system according to claim 1, characterized in that: The step 3 specifically includes: Step 3.1, the resistance value of the control system load is R1, voltage is applied and the system is judged to be working normally; the voltage U1 and current I1 at the output end of the high-frequency inverter are recorded at this time; Step 3.2, the resistance value of the control system load is R2, the voltage is applied and it is judged that the system is working normally; the voltage U2 and current I2 at the output end of the high-frequency inverter are recorded at this time; Step 3.3, the resistance value of the control system load is R3, the voltage is applied and it is judged that the system works normally; the voltage U3 and current I3 at the output end of the high-frequency inverter are recorded at this time; Step 3.4, calculate the input impedance of the system Z1 = U1 / I1, Z2 = U2 / I2, Z3 = U3 / I3 respectively; In the formula, Z1, Z2, and Z3 represent the system input impedance when the system works under three kinds of loads; U1, U2, and U3 represent the high-frequency inverter output terminal voltage when the system works under three kinds of loads; I1, I2, and I3 represent the high-frequency inverter output terminal current when the system works under three kinds of loads.

4. The method for identifying parameters of a quadrupole underwater electric field wireless power transmission system according to claim 1, characterized in that: The step 4 specifically includes: Step 4.1, simplifying the system circuit into an equivalent circuit when the system is resonant; Step 4.2, the equations obtained based on the equivalent circuit at resonance are as follows: In the formula, a1, a2, a3, b1, b2, and b3 represent intermediate variables.

5. A method for identifying parameters of a quadrupole underwater electric field type wireless power transmission system according to claim 4, characterized in that: The high-frequency inverter adopts a single-phase full-bridge inverter circuit, and the output voltage is a square wave with a fixed duty cycle. The output voltage satisfies the formula: Among them U ab is the fundamental effective value of the high frequency inverter output voltage, V DC is the output DC voltage value of the DC power supply.

6. The method for identifying parameters of a quadrupole underwater electric field wireless power transmission system according to claim 1, characterized in that: The emitter plate module includes a first plate, a third plate and a first compensation inductor; one end of the compensation inductor is connected to an output end of the high-frequency inverter, and the other end of the compensation inductor is connected to one end of the first plate; the other end of the third plate is connected to another output end of the high-frequency inverter; Among them, the inherent resonant frequency of the emitter plate module satisfies the formula: Among them, ω T represents the natural resonant frequency of the emitter plate module, C T Represents the capacitance value of the emitter plate, L T represents the compensating inductance of the emitter plate.

7. The method for identifying parameters of a quadrupole underwater electric field wireless power transmission system according to claim 1, characterized in that: The receiving plate module includes a second plate, a fourth plate and a second compensation inductor; one end of the compensation inductor is connected to the input end of the system load, and the other end of the compensation inductor is connected to one end of the second plate; the other end of the fourth plate is connected to the output end of the system load; Among them, the natural resonant frequency of the receiving plate module satisfies the formula: Among them, ω S Indicates the natural resonant frequency of the receiving plate module, C S Indicates the capacitance value of the receiving plate, L S Represents the compensation inductance of the receiving plate.

8. The method for identifying parameters of a quadrupole underwater electric field wireless power transmission system according to claim 1, characterized in that: The seawater equivalent impedance circuit consists of six resistors R 12 , R 13 , R 14 , R 23 , R 24 , R 34 Equivalent to three π-type resistors R Π1 , R Π2 , R Π3 ; Among them, the resistor R 12 , R 13 , R 14 , R 23 , R 24 , R 34 are the mutual resistances among the first electrode plate, the second electrode plate, the third electrode plate and the fourth electrode plate.

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