Underwater wireless power transmission system and method

Abstract

The invention provides an underwater wireless electric energy transmission system and method, the system comprises a primary end, a secondary end and an environment collection unit, the primary end is used for determining electric energy transmission efficiency according to a primary electric signal obtained by the primary end and a secondary electric signal obtained by the secondary end, and when the electric energy transmission efficiency is lower than a preset value, the environment collection unit is used for collecting the electric energy; determining a new working frequency within the working frequency adjustment range based on the current working frequency, determining a phase shift control signal under the new working frequency according to the secondary electric signal, and controlling the primary end to transmit electric energy to the secondary end according to the phase shift control signal; and the working frequency adjustment range is updated in real time according to the system environment parameters acquired by the environment acquisition unit. Phase shift control and frequency modulation control are combined, so that the whole wireless power transmission system runs at the highest efficiency for a long time, and the overall dynamic response performance is good.

Description

Technical Field

[0001] This invention relates to the field of deep-sea energy development and scientific research, and in particular to an underwater wireless power transmission system and method. Background Technology

[0002] In deep-sea energy development and various marine scientific research activities, power support and communication connections for various operational equipment and observation systems are generally achieved through wet-plug connectors. In actual operations, personnel use platforms such as remotely operated vehicles (ROVs) to connect the two ends of the wet-plug connectors. Compared to traditional wet-plug connectors, wireless power transfer systems do not rely on precise mating and do not carry the risks of mechanical wear and seal failure during the mating process, resulting in a longer service life. Furthermore, wireless power transfer systems are highly resistant to contamination, unaffected by seabed sediments and biological attachments, and do not require regular interface cleaning. In high-temperature and highly corrosive environments, wireless power transfer systems do not experience the risks associated with contact oxidation common with traditional wet-plug connectors. Therefore, wireless power transfer systems exhibit better environmental adaptability under certain special operating conditions.

[0003] Current underwater wireless power transfer systems are mainly designed based on the principle of magnetic induction coupling. The system generally consists of two parts: a primary side and a secondary side. When the system is working, the primary side generates a square wave with a fixed frequency and duty cycle, which drives the transmitting coil to convert electrical energy into magnetic energy. The secondary side generates an induced voltage through the receiving coil, and the output voltage is then regulated by a DC-DC voltage regulator unit.

[0004] Although the solution is technically mature and highly reliable, it has the following technical limitations in deep-water applications: 1) The system circuit is encapsulated in a sealed metal cavity, limiting heat dissipation. Electronic components operating at high temperatures for extended periods will experience temperature drift, leading to mismatch in system resonant parameters and reduced power transmission efficiency. The system's heat generation will further increase as transmission efficiency decreases, ultimately causing the entire system to malfunction.

[0005] 2) Under the same salinity and temperature conditions, the energy loss of a wireless power transfer system is closely related to the frequency of the alternating magnetic field; as the frequency increases, the energy loss also increases further. Therefore, the operating frequency of a deep-sea wireless power transfer system is constrained by the salinity and temperature of the current environmental medium.

[0006] 3) In actual operation, the impact of water flow will also cause changes in the relative positions between the primary and secondary terminals of the system, resulting in displacement between the transmitting and receiving coils, which in turn causes transient changes in the induced voltage at the secondary terminal. This places higher demands on the dynamic response capability of the system.

[0007] This shows that existing underwater wireless power transmission systems are inadequate in terms of the stability and reliability of power transmission. Summary of the Invention

[0008] To address the problems existing in the prior art, the present invention provides an underwater wireless power transmission system and method.

[0009] This invention provides an underwater wireless power transmission system, comprising a primary terminal, a secondary terminal, and an environmental acquisition unit. The primary terminal and the secondary terminal form an electrical energy-magnetic energy-electrical energy transmission architecture. The primary terminal is connected to an external voltage, and the secondary terminal is connected to an external load, wherein: The primary terminal is used to determine the power transmission efficiency based on the primary electrical signal it acquires and the secondary electrical signal acquired by the secondary terminal. When the power transmission efficiency is lower than a preset value, it determines a new operating frequency within the operating frequency adjustment range based on the current operating frequency. It also determines a phase-shift control signal at the new operating frequency based on the secondary electrical signal and controls the primary terminal to transmit power to the secondary terminal based on the phase-shift control signal. The operating frequency adjustment range is updated in real time based on the system environment parameters acquired by the environmental acquisition unit.

[0010] According to the present invention, an underwater wireless power transmission system is provided, wherein the primary end includes a control unit and a drive unit, wherein: The drive unit is connected to an external voltage to acquire the primary electrical signal; the control unit is connected to the environmental acquisition unit to acquire the system environmental parameters. The control unit is configured to determine the power transmission efficiency based on the primary electrical signal and the secondary electrical signal acquired by the secondary terminal, and when the power transmission efficiency is lower than a preset value, determine a new operating frequency within the operating frequency adjustment range based on the current operating frequency, and determine a phase-shift control signal at the new operating frequency based on the secondary electrical signal, and send the phase-shift control signal to the drive unit; it is also configured to update the operating frequency adjustment range in real time based on the system environmental parameters acquired by the environmental acquisition unit. The drive unit is connected to an external voltage and is used to control the duty cycle of the voltage inverter output waveform according to the phase shift control signal, so as to invert the external voltage into a voltage that starts the electrical energy to magnetic energy conversion process.

[0011] According to an underwater wireless power transmission system provided by the present invention, the primary end further includes a resonant unit and a transmitting coil. Correspondingly, the driving unit is used to invert an external voltage into an AC voltage to drive the transmitting coil, thereby enabling the transmitting coil to initiate an electrical-magnetic energy conversion process. The secondary end includes a receiving coil, a rectifier-filter unit, and a DC-DC voltage regulator unit. The resonant unit is connected to the driving unit and the transmitting coil, respectively. The receiving coil, the rectifier-filter unit, and the DC-DC voltage regulator unit are connected in sequence. The transmitting coil and the receiving coil establish an electrical-magnetic-electrical energy transmission channel.

[0012] According to an underwater wireless power transmission system provided by the present invention, the secondary electrical signal includes the input voltage of a DC-DC voltage regulator unit. Accordingly, the control unit is specifically used to: determine a phase-shift control signal at a new operating frequency based on the input voltage of the DC-DC voltage regulator unit.

[0013] According to the present invention, an underwater wireless power transmission system is provided, wherein the system environmental parameters include the current environmental medium salinity and the current environmental medium temperature, and correspondingly, the control unit is specifically used for: The maximum operating frequency within the operating frequency adjustment range is updated in real time based on the current salinity and temperature of the ambient medium. in, For maximum operating frequency, This is the proportionality coefficient. The maximum power loss that the system can withstand. The conductivity is the electrical conductivity at the first temperature and the first salinity value. and These are the temperature effect coefficient and the salinity effect coefficient, which affect the current dielectric conductivity, respectively. It is the difference between the current ambient temperature and the first temperature value. This is the difference between the current salinity of the ambient medium and the first salinity value. This is a correction value.

[0014] According to the present invention, an underwater wireless power transmission system is provided, wherein the driving unit includes a current sampling and conditioning circuit, a voltage sampling and conditioning circuit, a full-bridge topology circuit, and a gate driving circuit, wherein: The current sampling and conditioning circuit is connected to the external voltage to obtain the primary current signal; The voltage sampling and conditioning circuit is connected to the external voltage to obtain the primary voltage signal; The current path sampling and conditioning circuit is connected to the full-bridge topology circuit, and the full-bridge topology circuit outputs the inverted voltage. The gate drive circuit is connected to the full-bridge topology circuit and applies the phase-shift control signal to the full-bridge topology circuit, causing the full-bridge topology circuit to change the duty cycle of the voltage inverter output waveform.

[0015] According to the present invention, an underwater wireless power transmission system is provided, wherein the system environmental parameters further include the system operating temperature, and correspondingly, the primary terminal is further used for: When the system operating temperature reaches the first threshold, over-temperature protection is triggered; when the system operating temperature is lower than the second threshold, over-temperature protection is deactivated and the system restarts.

[0016] According to an underwater wireless power transmission system provided by the present invention, the primary terminal is further used for: When the primary input voltage is determined to be higher than the first upper limit value based on the primary electrical signal, or when the secondary output current is determined to be higher than the second upper limit value based on the secondary electrical signal, the system shuts down the power transmission operation.

[0017] According to an underwater wireless power transmission system provided by the present invention, the primary terminal is further used for: Once the number of times the system shuts down power transmission reaches a preset number, the system will enter a shutdown fault state.

[0018] The present invention also provides an underwater wireless power transfer method based on the above-mentioned underwater wireless power transfer system, comprising: Acquire the primary electrical signal corresponding to the primary terminal, and acquire the secondary electrical signal corresponding to the secondary terminal; The power transmission efficiency is determined based on the primary electrical signal and the secondary electrical signal, and when the power transmission efficiency is lower than a preset value, a new operating frequency is determined within the operating frequency adjustment range based on the current operating frequency. The phase-shift control signal at the new operating frequency is determined based on the secondary electrical signal, and the primary terminal is controlled to transmit electrical energy to the secondary terminal based on the phase-shift control signal; wherein, the operating frequency adjustment range is updated in real time according to the system environmental parameters.

[0019] This invention provides an underwater wireless power transmission system and method. The system determines the power transmission efficiency based on the primary electrical signal at the primary end and the secondary electrical signal at the secondary end. When the power transmission efficiency is lower than a preset value, a new operating frequency is determined within the operating frequency adjustment range based on the current operating frequency. Then, a phase-shift control signal is determined at the new operating frequency based on the secondary electrical signal. Finally, the system controls the transmission of power from the primary end to the secondary end based on the phase-shift control signal. By combining phase-shift control and frequency modulation control, the entire wireless power transmission system operates at its highest efficiency for extended periods, exhibiting excellent overall dynamic response performance. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in this 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 some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a diagram showing the external structure of the underwater wireless power transmission system provided by the present invention.

[0022] Figure 2 This is a schematic diagram of the underwater wireless power transmission system provided by the present invention.

[0023] Figure 3 This is a schematic diagram of the structure of the resonant unit provided by the present invention.

[0024] Figure 4 This is a schematic diagram of the control unit provided by the present invention.

[0025] Figure 5 This is a schematic diagram of the drive unit provided by the present invention.

[0026] Figure 6 This is a schematic diagram of the operation process of the underwater wireless power transmission system provided by the present invention.

[0027] Figure 7 This is a phase-shift control signal diagram provided by the present invention.

[0028] Figure 8 This is a frequency adjustment signal diagram provided by the present invention.

[0029] Figure 9 This is a flowchart illustrating the underwater wireless power transmission method provided by the present invention.

[0030] Figure 10 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0032] This invention provides an underwater wireless power transmission system, the structure of which is as follows: Figure 1As shown, the system consists of a primary end and a secondary end. The primary end structurally comprises an ROV operating handle, a first watertight connector, a primary end cap-1, a primary cavity, a primary end cap-2, and a guide component. The guide component, serving as a guide device for docking the primary and secondary ends, is made of non-metallic material and internally encapsulates a transmitting coil. Two temperature sensors and two salinity sensors are evenly embedded on its surface. The secondary end structurally comprises a second watertight connector, a secondary end cap-1, a secondary cavity, a secondary end cap-2, and a coil seal. (See also...) Figure 2 The circuit diagram shows the system's circuit composition. The primary cavity at the primary end integrates an auxiliary power supply, a control unit, a drive unit, a resonant unit, a transmitting coil, and a first wireless communication unit. The secondary cavity at the secondary end integrates a rectifier and filter unit, a DC-DC voltage regulator unit, a receiving coil, and a second wireless communication unit.

[0033] In this invention, to address the issue of system resonance parameter mismatch and decreased power transmission efficiency, a frequency modulation control strategy is employed to adjust the system's operating frequency, enabling the system to operate at its highest power transmission efficiency.

[0034] In ideal control models with relatively stable system structure and load, the voltage of a single port or the current in a single loop is often used as the basis for determining the system's frequency modulation. However, underwater wireless power transmission systems are prone to structural displacement due to factors such as water flow impact during actual operation. This displacement can easily lead to changes in the voltage of each port in the system. At the same time, fluctuations in the downstream load can also easily cause transient changes in the current of each loop in the system. Simply using voltage and current as parameters for frequency modulation control of the system is no longer applicable in practical applications. Practical engineering verification has shown that efficiency indicators better reflect the overall operating status of underwater wireless power transmission systems. Therefore, the system of this invention needs to monitor in real time the electrical signals inside the primary terminal (referred to as primary electrical signals for distinction, such as primary terminal input voltage, input current, etc.) and the electrical signals inside the secondary terminal (referred to as secondary electrical signals for distinction, such as secondary terminal input voltage, secondary terminal output voltage, secondary terminal output current, etc.). Then, based on the primary electrical signals acquired by itself and the secondary electrical signals acquired by the secondary terminal, the power transmission efficiency is determined. This power transmission efficiency can reflect the overall operating status of the underwater wireless power transmission system. When the power transmission efficiency is lower than the preset value, it is determined that the resonance parameters of the system have been mismatched during the power transmission process, that is, the overall working state of the system is not within the normal range. At this time, the system needs to start to find the frequency point with the highest efficiency. Therefore, a new working frequency is determined based on the current working frequency within the working frequency adjustment range.

[0035] Under the same salinity and temperature conditions, the energy loss of a wireless power transfer system is closely related to the frequency of the alternating magnetic field; as the frequency increases, the energy loss also increases further. Therefore, the operating frequency of an underwater wireless power transfer system is constrained by the salinity and temperature of the current environmental medium. Consequently, the operating frequency adjustment range needs to be updated in real-time based on the system environmental parameters obtained by the environmental acquisition unit. For example, the upper limit of the operating frequency adjustment range can be updated in real-time based on the system environmental parameters obtained by the environmental acquisition unit.

[0036] In this invention, the process of finding the most efficient frequency point and stabilizing the overall operating state of the system is not completed within one control cycle, but rather involves a frequency modulation process in each control cycle. After each frequency modulation, a phase shift control signal at the new operating frequency is determined based on the secondary electrical signal. Then, the voltage is transmitted from the primary terminal to the secondary terminal based on the phase shift control signal until the overall operating state of the system stabilizes, at which point the frequency modulation and phase shift control processes are stopped.

[0037] The underwater wireless power transmission system provided by this invention determines the power transmission efficiency based on the primary electrical signal at the primary end and the secondary electrical signal at the secondary end. When the power transmission efficiency is lower than a preset value, a new operating frequency is determined based on the current operating frequency within the operating frequency adjustment range. Then, a phase-shift control signal is determined at the new operating frequency based on the secondary electrical signal. Finally, the power is transmitted from the primary end to the secondary end according to the phase-shift control signal. By combining phase-shift control and frequency modulation control, the entire wireless power transmission system can operate at its highest efficiency for a long time and has good overall dynamic response performance.

[0038] In a further system of the above system, the primary end includes a control unit and a drive unit, wherein: The drive unit is connected to an external voltage to acquire primary electrical signals; the control unit is connected to an environmental acquisition unit to acquire system environmental parameters. The control unit is used to determine the power transmission efficiency based on the primary electrical signal and the secondary electrical signal acquired from the secondary terminal, and when the power transmission efficiency is lower than the preset value, to determine a new operating frequency within the operating frequency adjustment range based on the current operating frequency, and to determine the phase shift control signal at the new operating frequency based on the secondary electrical signal, and to send the phase shift control signal to the drive unit; it is also used to update the operating frequency adjustment range in real time based on the system environmental parameters acquired by the environmental acquisition unit. The drive unit is connected to an external voltage and is used to control the duty cycle of the voltage inverter output waveform according to the phase shift control signal, so as to invert the external voltage into the voltage that starts the electrical energy to magnetic energy conversion process.

[0039] Furthermore, the primary side also includes a resonant unit and a transmitting coil. Correspondingly, the driving unit is used to invert the external voltage into an AC voltage to drive the transmitting coil, enabling the transmitting coil to initiate the electrical energy-magnetic energy conversion process. The secondary side includes a receiving coil, a rectifier and filter unit, and a DC-DC voltage regulator unit; wherein, the resonant unit is connected to the driving unit and the transmitting coil respectively; the receiving coil, the rectifier and filter unit, and the DC-DC voltage regulator unit are connected in sequence; the transmitting coil and the receiving coil establish an electrical energy-magnetic energy-electrical energy transmission channel.

[0040] The resonant unit consists of a resonant inductor L1, a resonant capacitor C1, and a resonant capacitor C2, as shown in the specific structure below. Figure 3 As shown, the resonant unit is an LCC topology, consisting of two capacitors and one inductor. It is used to adjust the phase relationship between voltage and current in the circuit, enabling the MOSFET in the driver unit to operate in a soft-switching state. The network input of the resonant unit is connected to the output of the driver unit, and the output is connected to the transmitting coil. This circuit structure effectively cancels the self-inductance and leakage inductance of the transmitting coil, adjusts the phase relationship between the primary voltage and current, and enables the MOSFET in the front-end driver unit to operate in a soft-switching state, thereby reducing device losses and improving system efficiency.

[0041] In this invention, the control unit determines whether the system is operating at its resonant point by monitoring the current power transmission efficiency. If it is not at the resonant point, it is determined that the resonant parameters are mismatched. System resonant parameter mismatch refers to a situation in a system that utilizes resonance where key resonant parameters (mainly inductance L, capacitance C, and operating frequency f) deviate from their theoretically optimal matching values, causing the system to fail to achieve the expected resonant state or experience a significant performance degradation. To address this, the system of this invention determines that the resonant parameters are mismatched when the power transmission efficiency is lower than a preset value. A new operating frequency needs to be determined within the operating frequency adjustment range, aiming to find the frequency point with the highest efficiency; this is considered a frequency modulation process. This frequency modulation process is not completed within a single control cycle, but rather, within each control cycle, the frequency can be adjusted according to a preset adjustment gradient (e.g., 200Hz) until the frequency point with the best efficiency is found. In this invention, the frequency adjusted in each control cycle is considered the new operating frequency and applied to the power transmission operation in the new control cycle.

[0042] In this invention, the operating frequency adjustment range is updated in real time based on the system environmental parameters acquired by the environmental acquisition unit. The upper limit of the operating frequency adjustment range is constrained by the current salinity and temperature of the ambient medium; otherwise, the system energy loss will deteriorate sharply as the system operating frequency increases. Therefore, the system environmental parameters include the current ambient medium salinity and temperature. Accordingly, the control unit is specifically used for: The maximum operating frequency of the operating frequency adjustment range is updated in real time based on the current medium salinity and current medium temperature (in this invention, the minimum frequency of the operating frequency adjustment range can be preset to a fixed value).

[0043] in, For maximum operating frequency, This is the proportionality coefficient. The maximum power loss that the system can withstand. The conductivity is the electrical conductivity at the first temperature and the first salinity value. and These are the temperature effect coefficient and the salinity effect coefficient, which affect the current dielectric conductivity, respectively. It is the difference between the current ambient temperature and the first temperature value. This is the difference between the current salinity of the ambient medium and the first salinity value. This is a correction value.

[0044] In this invention, the primary and secondary terminals of the underwater wireless power transmission system are structurally and electrically independent and isolated. Wireless energy transmission between them is achieved through an "electrical energy-magnetic energy-electrical energy" conversion. The primary terminal receives a rated DC input of 350-400V, which is converted to 12V DC by an auxiliary power supply to power the control unit and wireless communication unit 1. The drive unit receives control signals from the control unit and inverts the input 350-400V DC power into AC power with a peak value of 700-800V. Therefore, the drive unit of this invention needs to control the duty cycle of the voltage inverter output waveform according to the phase-shift control signal to invert the external voltage into the voltage required to initiate the electrical-magnetic energy conversion process. After each frequency modulation, the control unit determines the phase-shift control signal at the new operating frequency based on the secondary electrical signal and then sends the phase-shift control signal to the drive unit.

[0045] In this invention, the transmitting coil completes the primary-side "electrical energy to magnetic energy" conversion. The secondary-side receiving coil receives electrical energy from the primary side through the "magnetic energy to electrical energy" conversion. The rectifier-filter unit converts the AC voltage generated in the receiving coil into a DC voltage. The DC-DC regulator unit converts the DC voltage output from the rectifier-filter unit into a stable voltage required by the load. Simultaneously, the DC-DC regulator unit includes input voltage sampling, output voltage sampling, and output current sampling functions. The second wireless communication unit is responsible for feeding back the parameters sampled by the DC-DC unit to the primary side. Correspondingly, the secondary electrical signal includes the input voltage of the DC-DC regulator unit. The control unit is specifically used to: determine the phase-shift control signal at the new operating frequency based on the input voltage of the DC-DC regulator unit.

[0046] See Figure 4The control unit is the core of the closed-loop control system. The microcontroller is responsible for executing the control algorithm within each control cycle; it interacts with the host computer via the first communication interface to exchange system commands and parameters; and it connects to the first wireless communication unit via the second communication interface to acquire secondary electrical signals. Control signals are output to the drive unit through the control port. Non-volatile memory stores system operating parameters, which are the initial configuration, such as power transmission on / off control, overvoltage and overcurrent protection thresholds, operating temperature range, and operating frequency adjustment range. The voltage conversion module converts the DC 12V input from the auxiliary power supply into the operating voltages required by the microcontroller, voltage sampling module, and current sampling module. The voltage and current sampling modules isolate and convert the primary voltage and current signals to their respective voltage ranges for the microcontroller. The sensor interface connects to the temperature and salinity sensors to acquire the temperature and salinity of the external environment.

[0047] like Figure 5 As shown, the driving unit includes a current sampling and conditioning circuit, a voltage sampling and conditioning circuit, a full-bridge topology circuit, and a gate driving circuit, wherein: The current sampling and conditioning circuit is connected to an external voltage (such as 375V) to obtain the primary current signal; The voltage sampling and conditioning circuit is connected to an external voltage to obtain the primary voltage signal; The current sampling and conditioning circuit is connected to the full-bridge topology circuit, and the full-bridge topology circuit outputs the inverted voltage. The gate drive circuit is connected to the full-bridge topology circuit and applies the phase-shift control signal to the full-bridge topology circuit, causing the full-bridge topology circuit to change the duty cycle of the voltage inverter output waveform.

[0048] The drive unit primarily inverts the input external voltage (such as rated 375V DC) into AC. The full-bridge topology consists of four MOSFETs: Q1, Q2, Q3, and Q4. Q1 and Q4, and Q2 and Q3 are referred to as diagonal MOSFETs. The full-bridge topology achieves DC-to-AC conversion through the alternating conduction of these four MOSFETs. The gate drive module receives control signals from the control unit and converts them into gate drive signals for the four MOSFETs. The current sampling and conditioning circuit, composed of sampling resistors and an operational amplifier, is responsible for obtaining the primary current signal (the input current at the primary terminal). The voltage sampling and conditioning circuit obtains the primary voltage signal (the input voltage at the primary terminal) through a series resistor voltage divider. The primary current and primary voltage signals are the parameters used by the control unit to calculate power transfer efficiency and perform overvoltage protection.

[0049] In this invention, the system environmental parameters also include the system operating temperature, and correspondingly, the primary terminal is also used for: When the system operating temperature reaches the first threshold, over-temperature protection is triggered; when the system operating temperature is lower than the second threshold, over-temperature protection is deactivated and the system restarts.

[0050] In this invention, the primary end is also used for: When the primary input voltage is determined to be higher than the first upper limit based on the primary electrical signal, or when the secondary output current is determined to be higher than the second upper limit based on the secondary electrical signal, the system shuts down power transmission. Then, after the system shuts down power transmission a preset number of times, it enters a shutdown fault state.

[0051] In this invention, the microcontroller's execution program for the control unit mainly includes system initialization, soft start, host computer communication, frequency modulation control, phase shift control, over-temperature protection, over-voltage and over-current protection, and shutdown fault functions. System soft start refers to a gradual and controllable startup process. It allows a system (whether electronic, mechanical, software, or an entire organization) to smoothly and stably transition from a shutdown or standby state to normal operation, avoiding the shock of suddenly applying full power or load.

[0052] Figure 6 The entire underwater wireless power transmission system is controlled by a control unit. After the system is powered on, it will execute the following steps: (1) The microcontroller inside the control unit reads system operating parameters from non-volatile memory, including power transmission on / off control, overvoltage and overcurrent protection thresholds, operating temperature range, and operating frequency adjustment range (initial configuration). Non-volatile memory refers to a type of computer memory that does not lose data after power failure.

[0053] (2) The system performs a self-test, which includes the host computer communication interface, the function of the drive unit, and the function of the wireless communication unit.

[0054] (3) After the self-test passes, check the current system operating parameters and system status parameters. If they do not meet the operating conditions, the system enters the shutdown fault state. If they do meet the conditions, the system enters the soft start state.

[0055] (4) In soft-start mode, the control unit will gradually open the phase shift angle limit of the control signal, and the upper limit of the duty cycle of the inverter output waveform of the drive unit will gradually be released. The process can be referred to Figure 7 This step is to prevent excessive current from flowing into the circuit during startup, which could affect the system.

[0056] (5) The system communicates with the host computer. The system obtains system operating parameters from the host computer and feeds back system status parameters to the host computer.

[0057] (6) The control unit determines the power transfer efficiency based on the primary electrical signal obtained from the primary terminal and the secondary electrical signal obtained from the secondary terminal. Based on the power transfer efficiency, it determines whether the circuit is operating at the predetermined resonant point. If the efficiency is lower than the system set value, it is determined that the resonant parameters are mismatched, and the control unit begins to search for the frequency point with the highest efficiency. The frequency adjustment process can be referred to... Figure 8 , Figure 8 In the figure, (a) and (b) are the control signal waveform and the inverter output waveform of the drive unit at different frequencies, respectively.

[0058] (7) The phase-shift control signal at the current frequency is generated by sampling the input voltage of the secondary DC-DC regulator unit, and then the duty cycle of the inverter output of the drive unit is adjusted.

[0059] (8) Over-temperature protection judgment. The system adopts hysteresis control for over-temperature protection. When the temperature reaches the high threshold, the system triggers over-temperature protection; when the temperature drops below the low threshold, the system releases the protection and performs a soft restart. The high threshold and low threshold can be set by the host computer.

[0060] (9) System overvoltage and overcurrent protection judgment. When the system detects that the primary input voltage or secondary output current is higher than the set threshold limit, the system will shut down the output. After the input voltage stabilizes, the system will perform a soft restart. Each trigger of overvoltage or overcurrent will accumulate one system fault. When the number of system faults reaches the upper limit, the system will enter a shutdown fault state and cannot recover automatically.

[0061] (10) The control signal is updated and output to the drive unit.

[0062] (11) Steps (5) to (10) constitute one control cycle. After step (10) ends, the system operation flow jumps back to step (5).

[0063] Within each control cycle, the control unit completes one frequency modulation control and one phase shift control. This combination of phase shift and frequency modulation effectively solves the problem of resonant element parameter mismatch in wireless power transmission systems, ensuring the system's power transmission efficiency, while also solving the problem of secondary voltage input overshoot caused by factors such as load changes and structural changes.

[0064] The underwater wireless power transmission method provided by the present invention is described below. The underwater wireless power transmission method described below can be referred to in correspondence with the underwater wireless power transmission system described above.

[0065] Figure 9 This invention illustrates an underwater wireless power transfer method based on the aforementioned underwater wireless power transfer system, comprising the following steps: Step 91: Obtain the primary electrical signal corresponding to the primary terminal and the secondary electrical signal corresponding to the secondary terminal.

[0066] Step 92: Determine the power transmission efficiency based on the primary and secondary electrical signals, and when the power transmission efficiency is lower than the preset value, determine a new operating frequency within the operating frequency adjustment range based on the current operating frequency.

[0067] Step 93: Determine the phase-shift control signal at the new operating frequency based on the secondary electrical signal, and control the transmission of electrical energy from the primary terminal to the secondary terminal based on the phase-shift control signal; wherein, the operating frequency adjustment range is updated in real time according to the system environmental parameters.

[0068] Since the method in this embodiment of the invention is based on the same principle as the system in the above embodiment, more detailed explanations will not be repeated here.

[0069] The underwater wireless power transmission method provided by this invention determines the power transmission efficiency based on the primary electrical signal at the primary end and the secondary electrical signal at the secondary end. When the power transmission efficiency is lower than a preset value, a new operating frequency is determined based on the current operating frequency within the operating frequency adjustment range. Then, a phase-shift control signal is determined at the new operating frequency based on the secondary electrical signal. Finally, the power is transmitted from the primary end to the secondary end according to the phase-shift control signal. By combining phase-shift control and frequency modulation control, the entire wireless power transmission system can operate at the highest efficiency for a long time, with good overall dynamic response performance.

[0070] Figure 10 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 10 As shown, the electronic device may include a processor 101, a communication interface 102, a memory 103, and a communication bus 104. The processor 101, communication interface 102, and memory 103 communicate with each other via the communication bus 104. The processor 101 can call logical instructions in the memory 103 to execute an underwater wireless power transmission method. This method includes: acquiring a primary electrical signal corresponding to the primary end and acquiring a secondary electrical signal corresponding to the secondary end; determining the power transmission efficiency based on the primary and secondary electrical signals, and when the power transmission efficiency is lower than a preset value, determining a new operating frequency within the operating frequency adjustment range based on the current operating frequency; determining a phase-shifting control signal at the new operating frequency based on the secondary electrical signal, and controlling the transmission of power from the primary end to the secondary end based on the phase-shifting control signal; wherein the operating frequency adjustment range is updated in real time according to system environmental parameters.

[0071] Furthermore, the logical instructions in the aforementioned memory 103 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0072] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the underwater wireless power transmission method provided by the above methods. The method includes: acquiring a primary electrical signal corresponding to the primary end and acquiring a secondary electrical signal corresponding to the secondary end; determining the power transmission efficiency based on the primary and secondary electrical signals, and determining a new operating frequency within the operating frequency adjustment range based on the current operating frequency when the power transmission efficiency is lower than a preset value; determining a phase-shifting control signal at the new operating frequency based on the secondary electrical signal, and controlling the primary end to transmit power to the secondary end based on the phase-shifting control signal; wherein the operating frequency adjustment range is updated in real time according to system environmental parameters.

[0073] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the underwater wireless power transmission method provided by the methods described above. The method includes: acquiring a primary electrical signal corresponding to a primary terminal and acquiring a secondary electrical signal corresponding to a secondary terminal; determining a power transmission efficiency based on the primary and secondary electrical signals, and when the power transmission efficiency is lower than a preset value, determining a new operating frequency within an operating frequency adjustment range based on the current operating frequency; determining a phase-shifting control signal at the new operating frequency based on the secondary electrical signal, and controlling the transmission of power from the primary terminal to the secondary terminal based on the phase-shifting control signal; wherein the operating frequency adjustment range is updated in real time according to system environmental parameters.

[0074] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0075] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An underwater wireless power transmission system, characterized in that, The system includes a primary terminal, a secondary terminal, and an environmental acquisition unit. The primary terminal and the secondary terminal form an electrical energy-magnetic energy-electrical energy transmission architecture. The primary terminal is connected to an external voltage, and the secondary terminal is connected to an external load, wherein: The primary terminal is used to determine the power transmission efficiency based on the primary electrical signal it acquires and the secondary electrical signal acquired by the secondary terminal. When the power transmission efficiency is lower than a preset value, it determines a new operating frequency within the operating frequency adjustment range based on the current operating frequency. It also determines a phase-shift control signal at the new operating frequency based on the secondary electrical signal and controls the primary terminal to transmit power to the secondary terminal based on the phase-shift control signal. The operating frequency adjustment range is updated in real time based on the system environment parameters acquired by the environmental acquisition unit.

2. The underwater wireless power transmission system according to claim 1, characterized in that, The primary end includes a control unit and a drive unit, wherein: The drive unit is connected to an external voltage to acquire the primary electrical signal; the control unit is connected to the environmental acquisition unit to acquire the system environmental parameters. The control unit is configured to determine the power transmission efficiency based on the primary electrical signal and the secondary electrical signal acquired by the secondary terminal, and when the power transmission efficiency is lower than a preset value, determine a new operating frequency within the operating frequency adjustment range based on the current operating frequency, and determine a phase-shift control signal at the new operating frequency based on the secondary electrical signal, and send the phase-shift control signal to the drive unit; it is also configured to update the operating frequency adjustment range in real time based on the system environmental parameters acquired by the environmental acquisition unit. The drive unit is connected to an external voltage and is used to control the duty cycle of the voltage inverter output waveform according to the phase shift control signal, so as to invert the external voltage into a voltage that starts the electrical energy to magnetic energy conversion process.

3. The underwater wireless power transmission system according to claim 2, characterized in that, The primary side also includes a resonant unit and a transmitting coil. Correspondingly, the driving unit is used to invert the external voltage into an AC voltage to drive the transmitting coil, so that the transmitting coil starts the electrical energy-magnetic energy conversion process. The secondary side includes a receiving coil, a rectifier and filter unit, and a DC-DC voltage regulator unit. The resonant unit is connected to the driving unit and the transmitting coil respectively. The receiving coil, the rectifier and filter unit, and the DC-DC voltage regulator unit are connected in sequence. The transmitting coil and the receiving coil establish an electrical energy-magnetic energy-electrical energy transmission channel.

4. The underwater wireless power transmission system according to claim 3, characterized in that, The secondary electrical signal includes the input voltage of the DC-DC regulator unit. Accordingly, the control unit is specifically used to: determine the phase-shift control signal at the new operating frequency based on the input voltage of the DC-DC regulator unit.

5. The underwater wireless power transmission system according to claim 2 or 4, characterized in that, The system environmental parameters include the current environmental medium salinity and the current environmental medium temperature. Accordingly, the control unit is specifically used for: The maximum operating frequency within the operating frequency adjustment range is updated in real time based on the current salinity and temperature of the ambient medium. in, For maximum operating frequency, This is the proportionality coefficient. The maximum power loss that the system can withstand. The conductivity is the electrical conductivity at the first temperature and the first salinity value. and These are the temperature effect coefficient and the salinity effect coefficient, which affect the current dielectric conductivity, respectively. It is the difference between the current ambient temperature and the first temperature value. This is the difference between the current salinity of the ambient medium and the first salinity value. This is a correction value.

6. The underwater wireless power transmission system according to claim 2, characterized in that, The driving unit includes a current sampling and conditioning circuit, a voltage sampling and conditioning circuit, a full-bridge topology circuit, and a gate driving circuit, wherein: The current sampling and conditioning circuit is connected to the external voltage to obtain the primary current signal; The voltage sampling and conditioning circuit is connected to the external voltage to obtain the primary voltage signal; The current sampling and conditioning circuit is connected to the full-bridge topology circuit, and the full-bridge topology circuit outputs the inverted voltage. The gate drive circuit is connected to the full-bridge topology circuit and applies the phase-shift control signal to the full-bridge topology circuit, causing the full-bridge topology circuit to change the duty cycle of the voltage inverter output waveform.

7. The underwater wireless power transmission system according to claim 1, characterized in that, The system environmental parameters also include the system operating temperature; correspondingly, the primary terminal is also used for: When the system operating temperature reaches the first threshold, over-temperature protection is triggered; when the system operating temperature is lower than the second threshold, over-temperature protection is deactivated and the system restarts.

8. The underwater wireless power transmission system according to claim 7, characterized in that, The primary end is also used for: When the primary input voltage is determined to be higher than the first upper limit value based on the primary electrical signal, or when the secondary output current is determined to be higher than the second upper limit value based on the secondary electrical signal, the system shuts down the power transmission operation.

9. The underwater wireless power transmission system according to claim 8, characterized in that, The primary end is also used for: Once the number of times the system shuts down power transmission reaches a preset number, the system will enter a shutdown fault state.

10. An underwater wireless power transmission method based on the underwater wireless power transmission system according to any one of claims 1 to 9, characterized in that, include: Acquire the primary electrical signal corresponding to the primary terminal, and acquire the secondary electrical signal corresponding to the secondary terminal; The power transmission efficiency is determined based on the primary electrical signal and the secondary electrical signal, and when the power transmission efficiency is lower than a preset value, a new operating frequency is determined within the operating frequency adjustment range based on the current operating frequency. The phase-shift control signal at the new operating frequency is determined based on the secondary electrical signal, and the primary terminal is controlled to transmit electrical energy to the secondary terminal based on the phase-shift control signal; wherein, the operating frequency adjustment range is updated in real time according to the system environmental parameters.

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