CN109546758B

CN109546758B - Underwater wireless power transmission system for transmitting signals by using distributed capacitors

Info

Publication number: CN109546758B
Application number: CN201811316125.XA
Authority: CN
Inventors: 刘华生; 牟宪民; 姚凯; 陈希有
Original assignee: Dalian University of Technology
Current assignee: Dalian University of Technology
Priority date: 2018-11-07
Filing date: 2018-11-07
Publication date: 2022-03-29
Anticipated expiration: 2038-11-07
Also published as: CN109546758A

Abstract

An underwater wireless power transmission system for transmitting signals by using distributed capacitors belongs to the technical field of wireless power transmission and comprises an energy transmission system and a signal transmission system. A high-frequency power supply at the transmitting side in the energy transmission system is connected with a compensation network at the transmitting side, the voltage output by the compensation network at the transmitting side is applied to a transmitting coil of the energy coupling mechanism, and the receiving side of the energy coupling mechanism receives energy and transmits the energy to the compensation network at the receiving side, and the energy is rectified by a high-frequency rectifying circuit to supply power to a load; a signal acquisition circuit in the signal transmission system transmits acquired load information to a signal modulation amplification circuit, a modulation signal is loaded to a transmitting side of a signal coupling mechanism, the signal coupling mechanism transmits the modulation signal obtained by a receiving side to a signal demodulation filtering circuit, and the load signal is output through demodulation filtering, so that synchronous transmission of energy and the signal is realized. The system can stably operate in respective frequency ranges; meanwhile, the signal is attenuated less underwater, and can be transmitted efficiently.

Description

Underwater wireless power transmission system for transmitting signals by using distributed capacitors

Technical Field

The invention provides a scheme for underwater induction type wireless power transmission and simultaneous signal transmission by using distributed capacitors of coils, and belongs to the technical field of non-electrical contact power transmission.

Background

The transmission of electrical energy through wires is the most common way of supplying power. Compared with the electric energy transmission mode of a wired cable, the non-contact wireless electric energy transmission mode has the characteristics of flexibility and easiness in use, and particularly has more remarkable superiority in special occasions such as damp, underwater, inflammable and explosive occasions and the like. For mobile equipment working in an underwater environment, when the mobile equipment needs to be replaced, underwater plugging and unplugging have great potential safety hazards. In actual work, the inductive coupling type wireless power transmission system is greatly influenced by factors such as operating conditions, environmental changes and the like, such as position changes of transmitting and receiving coils, system working frequency drift and the like. Under long-time work, the heating and aging of the coil and the switch tube can generate adverse effects on a wireless power system, so that the transmission efficiency and the power are reduced. In order to ensure the stability of the wireless power transmission system, the system needs to be controlled in a closed loop. Therefore, in the wireless power transmission system, signal transmission needs to be added in addition to the power transmission channel.

The non-electric contact power transmission technology utilizes the electromagnetic induction principle to carry out transmission. As a special power supply device, the transmission power, efficiency and robustness of the system are of great interest. In practical application, the transmission power and efficiency of the system should be improved on the basis of ensuring safety and reliability. In closed-loop control, the working current and voltage values of the circuit need to be acquired in real time, and the obtained signals are transmitted to the controller. According to the current research situation at home and abroad, energy and signals are transmitted simultaneously underwater, and the two existing solutions are adopted, namely, an additional signal transmission channel is added for transmitting information, so that independent transmission of energy and signals is realized. Such as a Zigbee or infrared radio frequency signal transmission method. But the method has complex system, higher cost and slower data transmission rate. Another method is to use two pairs of coils for signal transmission and energy transmission, respectively. The coil used for signal transmission has high current frequency and large current, generates large eddy current loss under water and has large influence on the transmission quality of a signal channel. Meanwhile, mutual coupling exists among the multiple coils, and large interference exists between energy and signals. The electric energy and the signal are synchronously transmitted by adopting a mode of combining the magnetic field and the electric field, so that the defect of wireless transmission only depending on the magnetic field can be effectively overcome. In underwater transmission, due to the large conductivity of seawater, distributed capacitance exists between coils and between the coils and the seawater compared with that in air. Therefore, a scheme for performing signal transmission by using distributed capacitance and performing energy transmission by using a coupling coil is provided.

Disclosure of Invention

The invention aims to solve the problem of larger channel interference when energy and signals are transmitted simultaneously in the conventional wireless power transmission system, and the scheme can realize independent simultaneous transmission of the energy and the signals and improve the stability of the wireless power transmission system. The signal transmission channel has high transmission frequency, and the frequency division technology is adopted, so that the frequency of an energy channel and the frequency of a signal transmission channel are not interfered in an induction type wireless electric energy transmission system, and the system can stably operate in respective frequency ranges; meanwhile, the electric field type wireless electric energy transmission technology is utilized for signal transmission, so that the signal is attenuated less underwater and can be transmitted efficiently; the advantages of large transmission power of an energy transmission path and small loss of a signal radio frequency transmission channel are fully utilized.

In order to achieve the purpose, the technical scheme of the invention is as follows:

an underwater wireless power transmission system for transmitting signals by using distributed capacitors comprises an energy transmission system and a signal transmission system, wherein load signals acquired by an energy receiving side are transmitted to an energy transmitting side for closed-loop control of the system, and the running stability and robustness of the system are improved.

The energy transmission system comprises a transmitting side high-frequency power supply, a transmitting side compensation network, an energy coupling mechanism, a receiving side compensation network, a high-frequency rectifying circuit and a load.

The high-frequency power supply at the transmitting side comprises a power frequency power supply, a low-frequency rectifying circuit and a high-frequency inverter circuit. The high-frequency inverter power supply provides required high-frequency energy for the energy coupling mechanism, the power frequency power supply is rectified by the low-frequency rectifying circuit to obtain direct-current voltage, the obtained direct-current voltage is inverted into high-frequency alternating current by the high-frequency inverter circuit and then is transmitted to the transmitting side compensation network, and the frequency is usually kHz. The transmitting side high frequency inverter power supply comprises a Royer oscillating circuit, an E type inverter circuit, a half bridge inverter circuit, a full bridge inverter circuit, a push-pull inverter circuit and the like. Different inverter topological structures are selected according to the required transmission power grade, and the soft switching technology is adopted to reduce the loss of the switching tube during the on and off.

The transmitting side compensation network enables the converted input impedance to be equivalent to a pure resistive load, reduces the reactive loss of the energy coupling mechanism in energy transmission, and improves the transmission power and efficiency. High-frequency odd harmonic components are filtered by the high-frequency square waves generated by the high-frequency power supply at the transmitting side through the compensating network at the transmitting side, and the obtained high-frequency fundamental waves are transmitted to the energy coupling mechanism. For an energy coupling mechanism formed by coils, a transmitting side compensation network usually comprises a capacitor or a series-parallel connection combination topology of the capacitor and the inductor, the T type or the pi type is common, and the specific structural form is determined by the output characteristic of a system and the parameters of the coupling mechanism. By the dual principle of the circuit, for a signal coupling mechanism consisting of a capacitor, the compensation network comprises an inductor or a combination of an inductor and a capacitor.

The energy coupling mechanism comprises a transmitting coil and a receiving coil, the transmitting coil is connected with a transmitting side compensation network, and high-frequency fundamental wave components are loaded on the transmitting coil. The alternating electric field produces a changing magnetic field in the coupling mechanism from the faraday's law of electromagnetic induction, which is likewise used to convert the changing magnetic field in the coupling mechanism into electrical energy in the receiving coil. The conversion of the electromagnetic power realizes the non-electric contact power transmission of the transmitting side and the receiving side. The coupling mechanism can be divided into two types of magnetic cores and non-magnetic cores, and the magnetic cores adopt high-frequency ferrite, permalloy or amorphous magnetically soft alloy under the high-frequency state. Mn-Zn ferrite is generally adopted and is characterized by high initial permeability and small high-frequency loss. Common core shapes include E-shaped, PU-shaped, EI-shaped, and the like. The coupling mechanism with the magnetic core has higher coupling coefficient and can transmit larger electric energy than the coupling mechanism without the magnetic core. The winding structure without the magnetic core is various, and the litz wire is adopted to manufacture the coupling mechanism so as to reduce the equivalent alternating current resistance. When the distances are the same, different coupling coefficients can be obtained by adopting different coupling modes. In the underwater transmission process, the coupling mechanism is firmly fixed, so that the variation of coil mutual inductance and distributed capacitance caused by the variation of coupling distance and coil dead area is reduced, the inaccurate matching of compensation parameters is caused, and the efficient and stable operation of the system is influenced. When non-electric contact electric energy transmission is carried out underwater, the size of distributed capacitance is greatly influenced by different winding modes, and a planar symmetrical non-magnetic core coupling mechanism is adopted for improving the distributed capacitance among coils.

The receiving side compensation network is connected with the receiving coil and used for adjusting the equivalent impedance of the receiving side to be a pure resistance characteristic, so that the receiving side reaches a resonance state in a high-frequency state, and the output power of the system is improved. The receiving side compensation network comprises capacitance or a combination network of capacitance and inductance, and the specific topological structure is determined by the output characteristic of the system and the parameters of the coupling mechanism.

The high-frequency rectification adopts a full-bridge rectification circuit consisting of fast recovery diodes, and the direct-current voltage is output through LC filtering or capacitance filtering voltage stabilization. The receiving side compensation network is connected with the receiving side high-frequency rectifying circuit and then provides electric energy for the load.

The signal transmission system comprises a signal acquisition circuit, a signal modulation amplification circuit, a signal coupling mechanism and a signal demodulation filtering circuit.

And the signal acquisition circuit is connected with the output of the high-frequency rectification filter circuit at the receiving side of the energy transmission mechanism and acquires the working voltage or current of the load. The sampled value obtained by signal detection is compared with the reference voltage by a comparison circuit, and is output as digital signals '0' and '1' after level conversion.

The signal modulation amplifying circuit is used for loading digital signals '0' and '1' obtained by level conversion into the signal coupling mechanism in a mode of controlling high-frequency carrier waves. The high frequency carrier frequency is usually MHz to eliminate the interference between the signal channel and the energy transmission channel. Common digital signal modulation schemes include Amplitude Shift Keying (ASK), Frequency Shift Keying (FSK), and Phase Shift Keying (PSK) depending on the characteristics of the carrier. In a non-contact electric energy transmission system, the selection of a signal modulation mode needs to be comprehensively considered in combination with the circuit design difficulty, the influence of signals on an energy transmission channel, the convenience degree of signal detection and the like. In order to ensure the effective transmission of signals within the coupling distance, a power amplifier circuit is adopted to amplify and output the signals.

The signal coupling mechanism is parasitic capacitance between the coupling coils. The signal coupling mechanism is divided into a signal transmitting capacitor and a receiving capacitor. Compared with the air, the seawater has larger conductivity (generally 0S/m in the air and 4S/m in the seawater), and parasitic capacitance between coils is formed between the coupling mechanisms; in a high-frequency system, for a plurality of strands of wires, turn-to-turn capacitance and distributed capacitance of a coil to seawater need to be considered. The turn-to-turn capacitance of the high-frequency coil and the equivalent capacitance of the coupling mechanism to the seawater are simplified into a parallel capacitance branch circuit of the coupling mechanism. The parasitic capacitance between the coupling mechanisms is bridged between the coupling inductors. The signal modulation amplifying circuit loads a modulation signal to the signal transmitting capacitor, and the signal output by the modulation amplifying circuit is coupled to the signal receiving capacitor in an electric field type wireless electric energy transmission mode. When the capacitor is used for signal transmission underwater, the signal attenuation loss is small, and meanwhile, as the energy of the signal transmission is small, the problem of capacitor insulation does not need to be considered, namely, more process treatment on the coil is not needed.

The signal demodulation filter circuit is used for modulating the carrier wave with the digital signal received by the signal coupling mechanism into digital signals '0' and '1'. Signal demodulation is divided into non-coherent demodulation and coherent demodulation methods. In a non-contact electric energy transmission system, a carrier synchronization signal cannot be accurately obtained in a signal extraction side, and in order to ensure the transmission of the signal, a non-coherent demodulation method is adopted. The method has two modes of amplitude keying and frequency shift keying. The demodulation circuit comprises a voltage division network, an isolation transformer, a voltage follower, an envelope detector, a low-pass filter and a comparator. The signal demodulation filtering circuit is used for extracting the modulation signal in the signal coupling mechanism receiving capacitor and consists of a voltage division circuit, a voltage follower, an envelope detector and a low-pass filter. The envelope detector carries out envelope processing on the alternating current amplitude by utilizing the characteristic of unidirectional conduction of the diode and the charge-discharge process of the resistor and the capacitor. The signal with the enveloping property obtained by the detector is subjected to low-pass filtering to remove high-frequency components and noise, so that square waves of a low-frequency link are obtained, and finally, digital signals are demodulated through voltage comparison, so that signal communication from the energy receiving side to the transmitting side is realized.

The square wave generated by the high-frequency power supply at the transmitting side is connected to a compensation network at the transmitting side, the high-frequency sinusoidal voltage output by the compensation network at the transmitting side is applied to a transmitting coil of the energy coupling mechanism, and the receiving side of the energy coupling mechanism receives energy and transmits the energy to the compensation network at the receiving side, and the energy is rectified by a high-frequency rectifying circuit to supply power to a load; the signal acquisition circuit transmits the acquired load information to the signal modulation amplification circuit, and the modulation signal obtained by modulation amplification processing is loaded to the transmitting side of the signal coupling mechanism, wherein the signal coupling mechanism is a distributed capacitor of the energy coupling mechanism during underwater wireless power transmission; the signal coupling mechanism transmits the modulation signal obtained by the receiving side to a signal demodulation filtering circuit, and outputs a load signal through demodulation filtering; and synchronous transmission of energy and signals is realized.

The invention has the beneficial effects that:

1) synchronous transmission of energy and signals in an underwater environment is realized, a real-time load working state can be obtained, closed-loop control is further conveniently realized, and the robustness of a wireless power transmission system is improved;

2) parasitic capacitance between coils is directly used as a signal transmission channel during underwater wireless power transmission, and an additional signal transmission mechanism and a complex control circuit are not required to be additionally arranged. The magnetic field is used for energy transmission, the electric field is used for signal transmission, mutual interference between the magnetic field and the electric field is small, and the signals can be accurately transmitted while energy is efficiently transmitted;

3) the energy coupling mechanism is compensated, so that the transmission capability and efficiency of the system are improved; when the energy coupling mechanism is designed for compensation, the parallel capacitance branch of the coupling mechanism is used as a part of compensation parameters.

4) Amplitude keying is adopted for signal modulation and demodulation, the carrier amplitude is controlled, and noncoherent demodulation is utilized for transmitting signals.

Drawings

Fig. 1 is a mutual inductance model of a coil and considering parasitic capacitance under an underwater working state. (a) Is a coupling coil model, and (b) is an underwater coupling coil mutual inductance model considering parasitic capacitance.

Fig. 2 is a system block diagram of signal transmission between underwater induction type wireless power transmission and distributed capacitance.

Fig. 3(a) is a schematic diagram of a signal modulation circuit using amplitude keying, and fig. 3(b) is a signal demodulation circuit using amplitude keying.

FIG. 4(a) is a schematic diagram of energy transfer; fig. 4(b) is a schematic diagram of signal transmission.

Detailed description of the preferred embodiments

The invention will be described in detail through the drawings and technical scheme in the specification. It should be understood, however, that structures and features of the invention may be incorporated in other embodiments without further recitation.

Referring to fig. 1, since seawater has a large conductivity, when a high-frequency current flows through the energy coupling mechanism, a parasitic capacitance C is generated between the coupling coils_MThe calculation formula is as follows:

C_M＝ε₀ε_rσS/d

wherein epsilon₀、ε_rRespectively, vacuum and dielectric permittivity, sigma dielectric conductivity, and S, d coil cross-sectional area and coil pitch.

Turn-to-turn capacitance C for coils at high frequencies_p-self、C_s-selfThe schematic diagram is shown in FIG. 1 (b). For convenient analysis, the multi-turn litz wire is equivalent to a single-turn coil. Neglecting the insulating layer, the turn-to-turn capacitance is:

considering the influence of the thickness of the insulating layer on the capacitance, the capacitance between the air gap and the insulating layer is:

the value of the interturn capacitance is the series value of Cr and Cg when considering the insulating layer. The total inter-turn capacitance of the N turns of coil is:

wherein r is the coil radius; l is the coil spacing between the single layers; and a is the thickness of the insulating layer.

With continued reference to fig. 1(b), the high-frequency current flowing through the transmitting-side coil generates a varying magnetic field, and a varying electromotive force is generated in the seawater by faraday's law of electromagnetic induction, and since the seawater has a conductive property, a part of heat loss, which is eddy current loss of the energy coupling mechanism, is generated.

Fig. 2 is a system block diagram of the signal transmission between the underwater induction type wireless power transmission and the distributed capacitor according to the present invention. A scheme for synchronously transmitting signals based on inductive wireless power transmission and distributed capacitance applied underwater comprises a transmitting side high-frequency inverter power supply, a transmitting side compensation network, a transmitting coil, a receiving side compensation network, a high-frequency rectification circuit and a load. The signal transmission channel comprises modules for signal acquisition, signal modulation and amplification, signal demodulation and the like. The low-frequency rectifying circuit rectifies the power frequency power supply into direct current which is used as the input of the high-frequency inverter circuit. And filtering high-order components of the high-frequency square waves obtained by inverting output through a transmitting side compensation network, and loading the high-order components to a transmitting coil. The energy is converted into a magnetic field through an electric field and then into electric energy on a receiving coil. And finally, the load is loaded to a load after the compensation of the receiving side and the high-frequency rectification and filtration. The signal transfer direction is from the energy receiving coil to the transmitting coil. Comparing the collected load signal with reference voltage, and outputting the load signal and the reference voltage as digital signals of '0' and '1' according to a certain rule, and loading the signals to a signal coupling mechanism through power amplification, and performing signal demodulation and filtering on a signal receiving side.

By contrast, in the wireless power transmission technology, amplitude keying is used for signal modulation and demodulation. The signal characteristics are expressed by the amplitude of the carrier wave, and the switch is controlled by the state of the modulation signal, so that the signal with the same amplitude state as the carrier wave is obtained. The switching frequency is much higher than the power transmission frequency, often MHz. The signal modulation circuit is essentially a multiplier circuit. Fig. 3(a) is a schematic diagram of a signal modulation circuit using amplitude keying. S₁、S₂For a field effect transistor working in a switching state, the working state can be divided into:

1) when u is_signal＝1，u′_signalWhen equal to 0, S₁Conduction, S₂Cut-off at this time u_o＝u_i；

2) When u is_signal＝0，u′_signalWhen 1, S₁Cutoff, S₂Is turned on at this time u_o＝0。

Fig. 3(b) shows a signal demodulation circuit using amplitude keying. A diode detection circuit is adopted, alternating current signals containing two amplitudes are enveloped by utilizing the charge-discharge process of a resistor capacitor, and the signals are filtered by a low-pass filter circuit to remove high-frequency harmonic waves. And a voltage comparison circuit is adopted, and the reference voltage is compared with the voltages with different amplitudes and then the signals are output.

FIG. 4(a) is a schematic diagram of a power transmission channel only, with two coils as the coupling mechanism, oriented from the transmit side to the receive side; fig. 4(b) shows the signal transmission process from the receiving side to the transmitting side. Energy and signals respectively adopt a magnetic field and an electric field as transmission media, and mutual interference is small. The signal transmission frequency is far greater than that of an energy transmission channel, the coil self-inductance has large equivalent impedance during signal transmission, and the signal transmission is approximately broken circuit treatment; similarly, in the process of electric energy transmission, the parasitic capacitance and turn-to-turn capacitance between coils are subjected to disconnection treatment in the seawater environment.

The invention transmits the load signal acquired by the energy receiving side to the energy transmitting side for closed-loop control of the system, thereby improving the operation stability and robustness of the system. In the underwater induction type wireless power transmission system, in the power transmission process, a large distributed capacitance exists between the transmitting side and the receiving side of the coupling coil.

The above-mentioned embodiments only express the embodiments of the present invention, but not should be understood as the limitation of the scope of the invention patent, it should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the concept of the present invention, and these all fall into the protection scope of the present invention.

Claims

1. an underwater wireless power transmission system utilizing distributed capacitance transmission signal, is characterized in that, described underwater wireless power transmission system comprises energy transmission system and signal transmission system, and the load signal that the energy receiving side collects is transmitted to The energy emission side performs the closed-loop control of the system;

The energy transmission system includes a transmitter-side high-frequency power supply, a transmitter-side compensation network, an energy coupling mechanism, a receiver-side compensation network, a high-frequency rectifier circuit and a load;

The high-frequency power supply on the transmitting side includes a power frequency power supply, a low-frequency rectifier circuit and a high-frequency inverter circuit. The power frequency power supply is rectified by the low-frequency rectifier circuit to obtain a DC voltage, and the obtained DC voltage is converted by the high-frequency inverter circuit into a high-frequency AC voltage. Then, it is transmitted to the compensation network on the transmitting side; the compensation network on the transmitting side makes the transformed input impedance equivalent to a pure resistive load, and the high-frequency square wave generated by the high-frequency power supply on the transmitting side passes through the compensation network on the transmitting side, and the resulting high-frequency fundamental wave is transmitted. to the energy coupling mechanism; the energy coupling mechanism includes a transmitter coil and a receiver coil, the transmitter coil is connected to the transmitter side compensation network, and the high-frequency fundamental wave component is loaded on the transmitter coil; the receiver side compensation network is connected to the receiver coil for adjusting the receiver side. The equivalent impedance is embodied as pure resistance characteristics, so that the receiving side reaches a resonance state under high frequency; the high-frequency rectifier circuit adopts a full-bridge rectifier circuit, which is regulated by LC filtering or capacitor filtering to output DC voltage, and the receiving side compensates the network After connecting with the high-frequency rectifier circuit on the receiving side, it provides power for the load;

The signal transmission system includes a signal acquisition circuit, a signal modulation and amplification circuit, a signal coupling mechanism, and a signal demodulation filter circuit;

The signal acquisition circuit is connected to the output of the high-frequency rectification filter circuit on the receiving side of the energy transmission mechanism, collects the working voltage or current of the load, compares the sampled value obtained by signal detection with the reference voltage through the comparison circuit, and performs level conversion to output a digital signal. The signal modulation and amplification circuit is used to load the digital signal obtained by level conversion into the signal coupling mechanism by controlling the high-frequency carrier, and the signal modulation and amplification circuit loads the modulation signal into the signal transmitting capacitor, and transmits the signal through the electric field radio The signal output from the modulation and amplifying circuit is coupled to the signal receiving capacitor in a way that can transmit; the signal coupling mechanism is the parasitic capacitance between the coupling coils, the signal coupling mechanism is divided into a signal transmitting capacitor and a receiving capacitor, and the parasitic capacitance between the coupling mechanisms is bridged. between the coupled inductors; the signal demodulation filter circuit is used to modulate the carrier wave with the digital signal received by the signal coupling mechanism into a digital signal; in the non-contact power transmission system, a non-coherent demodulation method is used;

The high-frequency power supply on the transmitting side is connected to the compensation network on the transmitting side. The voltage output by the compensation network on the transmitting side is applied to the transmitting coil of the energy coupling mechanism. The receiving side of the energy coupling mechanism receives energy and transmits it to the compensation network on the receiving side. The rectifier circuit rectifies the power supply for the load; the signal acquisition circuit transmits the collected load information to the signal modulation and amplification circuit, and after modulation and amplification processing, the obtained modulation signal is loaded into the transmitting side of the signal coupling mechanism. When the signal coupling mechanism is underwater wireless power transmission The distributed capacitance of the energy coupling mechanism; the signal coupling mechanism transmits the modulated signal obtained on the receiving side to the signal demodulation filter circuit, and outputs the load signal after demodulation and filtering; realizes the synchronous transmission of energy and signal.

2. a kind of underwater wireless power transmission system utilizing distributed capacitance transmission signal according to claim 1, is characterized in that, described signal demodulation filter circuit is used for extracting the modulation signal in the signal coupling mechanism receiving capacitance, the signal The demodulation filter circuit is composed of a voltage divider circuit, a voltage follower, an envelope detector and a low-pass filter. Network processing; the signal with envelope properties obtained by the detector is filtered through the low-pass filter link to filter out high-frequency components and noise, and the square wave of the low-frequency link is obtained, and finally the digital signal is demodulated through voltage comparison to realize the energy receiving side. Signal communication on the transmit side.

3. a kind of underwater wireless power transmission system utilizing distributed capacitance transmission signal according to claim 1 and 2, is characterized in that, for the energy coupling mechanism that coil is formed, described transmitting side compensation network comprises a capacitor or capacitor The series-parallel combination topology with the inductor, the specific structural form is determined by the output characteristics of the system and the parameters of the coupling mechanism.

4. a kind of underwater wireless power transmission system utilizing distributed capacitance transmission signal according to claim 1 and 2, is characterized in that, when carrying out non-electrical contact electric power transmission underwater, described energy coupling mechanism adopts plane type Symmetrical coreless coupling mechanism.

5. a kind of underwater wireless power transmission system utilizing distributed capacitance transmission signal according to claim 3, is characterized in that, when carrying out non-electrical contact power transmission underwater, described energy coupling mechanism adopts plane symmetrical Coreless coupling mechanism.

6. A kind of underwater wireless power transmission system utilizing distributed capacitance to transmit signal according to claim 1 or 2 or 5, is characterized in that, described receiving side compensation network comprises capacitance or the combined network of capacitance and inductance, specifically The topology is determined by the system output characteristics and coupling mechanism parameters.

7. A kind of underwater wireless power transmission system utilizing distributed capacitance transmission signal according to claim 3, is characterized in that, described receiving side compensation network comprises capacitance or the combined network of capacitance and inductance, and the specific topology structure is determined by the system The output characteristics and coupling mechanism parameters are determined.

8. A kind of underwater wireless power transmission system utilizing distributed capacitance to transmit signals according to claim 4, is characterized in that, described receiving side compensation network comprises capacitance or the combined network of capacitance and inductance, and the specific topology structure is determined by the system The output characteristics and coupling mechanism parameters are determined.