An adaptive impedance matching device for underwater low-frequency underwater acoustic transducer

Abstract

The present invention discloses an adaptive underwater low-frequency underwater acoustic transducer impedance matching device, which comprises a main control circuit, which sends a sweep frequency signal to an underwater power amplifier in a configuration stage and performs impedance matching calculation according to an electrical signal collected by an impedance detection circuit; in an adaptive operation stage, calculates an expected sound source response curve according to the transmitting power of the underwater power amplifier, obtains a power deviation in combination with the sound source signal collected by a hydrophone, obtains an impedance angle according to the electrical signal collected by the impedance detection circuit, and then performs impedance matching modification; an impedance array circuit realizes a circuit with adjustable inductance and inductance parameters to output the maximum power of the underwater acoustic transducer; in the configuration stage, the impedance detection circuit collects electrical signals of the impedance array circuit at various frequency points and transmits them to the main control circuit; in the adaptive operation stage, the electrical signals of the transmitting frequency points are collected and transmitted to the main control circuit; and an impedance switching circuit selectively connects the capacitors and inductors in the impedance array circuit by a relay according to the matching impedance of the main control circuit.

Description

Technical Field

[0001] The present invention relates to the field of underwater observation technology, and in particular to an adaptive underwater low-frequency underwater acoustic transducer impedance matching device. Background Art

[0002] The seabed observation network uses submarine cables to realize power supply and communication between shore-based and underwater equipment. Underwater high-power sound sources play a vital role in the seabed observation network.

[0003] The underwater sound source system is installed on the seabed, such as Figure 1 As shown, it consists of a signal source, an underwater power amplifier, an impedance matching device, an underwater acoustic transducer and a hydrophone. The impedance matching device is an important device that determines the sound efficiency and service life of the underwater acoustic transducer. Improper impedance matching will lead to a large amount of energy loss, heating and damage of the transducer and other problems.

[0004] The following problems are often encountered in transducer impedance matching:

[0005] 1. There are many types of transducers deployed underwater, and each has different impedance characteristics. Different transducers require separate impedance matching, which makes the parameter configuration process complicated and the customized design cost high.

[0006] 2. During the operation of the transducer on the seabed, its own impedance characteristics are affected by environmental parameters such as pressure and density. It is impossible to simulate the actual operating conditions through onshore testing or lake testing, and it is difficult to accurately match the impedance parameters during actual operation on the seabed.

[0007] 3. When the transducer is operating on the seabed, its impedance characteristics will change due to heat generation during operation, showing dynamic characteristics. The use of an impedance matching device with fixed parameters cannot ensure that the transducer is in good working condition throughout the entire working process.

[0008] Existing impedance matching devices for low-frequency underwater acoustic transducers either use large filter parameters for inefficient matching or use Butterworth filters to expand bandwidth for matching. However, the calculation of such filter parameters is complex and engineering implementation is difficult. Summary of the Invention

[0009] The purpose of the present invention is to overcome the above-mentioned defects of the prior art and thus provide an adaptive underwater low-frequency acoustic transducer impedance matching device that can meet the matching requirements of a variety of low-frequency transducers and dynamically adjust parameters according to the real-time impedance characteristics of the transducer after heating, thereby ensuring long-term, efficient and stable operation of the underwater transducer.

[0010] In order to achieve the above-mentioned object, the present invention provides an adaptive underwater low-frequency underwater acoustic transducer impedance matching device for use in an underwater sound source system of a seabed observation network, comprising a configuration phase and an adaptive operation phase. The device comprises: a main control circuit, an impedance array circuit, an impedance detection circuit, and an impedance switching circuit, wherein:

[0011] The main control circuit is used to send a sweep frequency signal within a set frequency range to the underwater power amplifier during the configuration phase, and perform impedance matching calculations based on the electrical signals at each frequency point collected by the impedance detection circuit. It is also used to calculate the expected sound source response curve based on the transmitted power of the underwater power amplifier during the adaptive operation phase, obtain a power deviation based on the sound source signal collected by the hydrophone, calculate the impedance angle based on the electrical signal collected by the impedance detection circuit, and then modify the impedance matching based on the power deviation and the impedance angle.

[0012] The impedance array circuit is used to adopt a multi-resonance point broadband matching scheme to realize a circuit with different adjustable inductance and capacitance parameters by connecting multiple groups of inductors and capacitors in series and parallel, and to connect specific circuits according to the impedance switching circuit to achieve maximum power output for the underwater acoustic transducer;

[0013] The impedance detection circuit is used to collect electrical signals of the impedance array circuit at various frequencies during the configuration phase and transmit them to the main control circuit; and is also used to collect electrical signals of the transmission frequency points during the adaptive operation phase and transmit them to the main control circuit;

[0014] The impedance switching circuit is used to selectively connect the capacitors and inductors in the impedance array circuit through relays according to the matching impedance calculated by the main control circuit.

[0015] Preferably, the device is deployed between the underwater power amplifier and the underwater acoustic transducer, or integrated into the underwater power amplifier, and the external interfaces include: a power input interface and a communication interface connected to the underwater power amplifier, and a power output interface connected to the underwater acoustic transducer.

[0016] Preferably, the main control circuit is implemented based on an MCU, DSP or FPGA chip.

[0017] Preferably, in the main control circuit, impedance matching calculation is performed based on the electrical signals of each frequency point collected by the impedance detection circuit; including:

[0018] The power input port voltage signal, power input port current signal, power output port voltage signal and power output port current signal collected by the impedance detection circuit are used to calculate the real-time impedance Z, transmission power P2 and impedance angle θ according to the pulse IV measurement method.

[0019] Preferably, the main control circuit calculates an expected sound source response curve based on the transmitted power of the underwater power amplifier, obtains a power deviation based on the sound source signal collected by the hydrophone, calculates an impedance angle based on the electrical signal collected by the impedance detection circuit, and then performs impedance matching modification based on the power deviation and the impedance angle; including:

[0020] Based on the transmitted power P1 of the underwater power amplifier, the transmitted power P2 collected and calculated by the impedance detection circuit, and the received power P3 collected by the hydrophone, the power deviation ΔP is obtained by the following formula:

[0021] ΔP=k1*(P1-P2)+k2*(P2-P3)

[0022] Among them, k1 and k2 are calibration coefficients;

[0023] The impedance parameters are closed-loop controlled according to the power deviation ΔP and the impedance angle θ, thereby completing the modification of the impedance matching.

[0024] Preferably, the impedance array circuit includes two groups of inductors and two groups of capacitors, wherein the first group of inductors is connected in series, the second group of inductors is connected in series, the first group of capacitors is connected in parallel, and the second group of capacitors is connected in parallel. The overall connection of the impedance array circuit is that the first group of inductors is connected in series with the first group of capacitors and then the second group of capacitors and the second group of inductors are connected in parallel.

[0025] Preferably, the impedance detection circuit uses a Hall sensor to collect signals.

[0026] Preferably, the processing process of the configuration stage includes:

[0027] Step 1) When the main control circuit confirms through communication that the underwater power amplifier is in a standby state, the impedance matrix is ​​set to an initial value;

[0028] Step 2) The main control circuit provides a set of sweep frequency signals within a set frequency range to the underwater power amplifier, including the sweep frequency bandwidth, frequency point interval, number of single frequency point transmission groups, and number of transmission cycles per group;

[0029] Step 3) The underwater power amplifier transmits in sequence according to the set information, and the impedance detection circuit collects the voltage and current signals of each frequency point and transmits them to the main control circuit; the main control circuit synchronously completes identification and records during the transmission of the underwater power amplifier;

[0030] Step 4) After the signal is sent, the main control circuit calculates the corrected impedance matrix value based on the collected voltage and current signals at each frequency point and modifies the impedance array matching parameters;

[0031] Step 5) Repeat steps 2) to 4) until the main control circuit determines that the impedance array matching parameter configuration is complete. The impedance switching circuit selects and connects the capacitors and inductors in the impedance array circuit through the relay according to the parameters configured by the main control circuit to achieve maximum power output of the underwater acoustic transducer.

[0032] Preferably, the processing process of the adaptive operation stage includes:

[0033] Step 1) The main control circuit calculates the expected sound source response curve according to the signal power of the underwater power amplifier;

[0034] Step 2) The main control circuit compares the expected sound source response curve with the sound source signal collected by the hydrophone and calculates the power deviation;

[0035] Step 3) The impedance detection circuit collects the impedance angle and transmits it to the main control circuit;

[0036] Step 4) The main control circuit converts the current and voltage signals obtained by the impedance detection circuit into an impedance angle, and combines the power deviation with the impedance angle to calculate the impedance matching state of the transducer, where the impedance angle is a dynamic parameter of the outer loop of the algorithm, and the power deviation is an integral parameter of the inner loop of the algorithm;

[0037] Step 5) The main control circuit monitors the impedance matching status of the transducer. When it exceeds the set limit, the device autonomously completes the adaptive parameter adjustment during the signal transmission interval, thereby maximizing the working efficiency of the underwater acoustic transducer without affecting the signal transmission status.

[0038] Compared with the prior art, the advantages of the adaptive underwater low-frequency underwater acoustic transducer impedance matching device provided by the present invention are:

[0039] 1. It can adapt to different types of underwater low-frequency transducers without the need for customized design for different transducers, greatly improving the working efficiency of the transducer and extending the working life of the transducer.

[0040] 2. The impedance matching parameter configuration process is simple to operate. All parameter configurations can be completed remotely on the software interface, without the need for manual mechanical operation of traditional transducer impedance matching devices.

[0041] 3. After construction and deployment, the parameters can be adjusted in real time according to the working status of the underwater power amplifier at any time to avoid impedance matching imbalance caused by a series of factors such as changes in the underwater acoustic environment of the transducer or heat and aging, thereby greatly improving the working efficiency and service life of the transmitting sound source. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 Schematic diagram of underwater sound source system;

[0043] Figure 2Schematic diagram of the adaptive underwater low-frequency acoustic transducer impedance matching device of the present invention;

[0044] Figure 3 is a schematic diagram of an impedance switching circuit;

[0045] Figure 4 Schematic diagram of closed-loop control of the main control circuit. DETAILED DESCRIPTION

[0046] The technical solution provided by the present invention is further illustrated below with reference to embodiments.

[0047] The technical solution of the present invention will now be described in further detail with reference to the accompanying drawings.

[0048] The internal components of the impedance matching device are as follows: Figure 2 As shown, it consists of a main control circuit, an impedance array circuit, an impedance detection circuit, and an impedance switching circuit.

[0049] The main control circuit can be composed of but not limited to logic chips such as MCU, DSP, FPGA, etc. to complete the overall algorithm calculation, protection judgment, communication and other functions of the impedance matching device.

[0050] The impedance array circuit adopts a multi-resonance point broadband matching solution, which can be composed of multiple sets of inductors and capacitors connected in series and parallel. This case takes four sets of capacitors and inductors connected in series and parallel as an example. Figure 3 As shown, each set of inductive and capacitive parameters is adjustable, and the basic parameter is selected as inductive, which is suitable for low-frequency spherical piezoelectric underwater acoustic transducer.

[0051] The impedance detection circuit collects information about the impedance array circuit, including input voltage, output voltage, input current, output current, input impedance angle, and output impedance angle, and transmits the collected electrical signals to the main control circuit for calculation. The impedance detection circuit uses Hall effect sensors for signal acquisition to avoid coupling with power circuit parameters and ensure accurate impedance matching.

[0052] Impedance switching circuit such as Figure 3 As shown in the figure, the capacitors and inductors in the impedance array are selectively connected through relays to determine the actual connection parameters of the final impedance matching device. The use of relays for switching can isolate the impedance coupling of the control circuit and ensure the accuracy of impedance matching. Figure 4 Shown is the closed-loop control schematic diagram of the main control circuit.

[0053] The working process of the impedance matching device is divided into two stages: configuration stage and adaptive operation stage.

[0054] The configuration phase process is as follows:

[0055] 1. The main control circuit communication confirms that the underwater power amplifier is in standby mode and the impedance matrix is ​​set to the initial value.

[0056] 2. The main control circuit provides a set of sweep frequency signals within the set frequency range to the underwater power amplifier, and sends the signal after the set delay.

[0057] 3. During the transmission process, the voltage and current signals at each frequency point are obtained through the impedance detection circuit.

[0058] 4. After the signal is sent, the main control circuit calculates the corrected impedance matrix value based on the collected voltage and current signals at each frequency point and modifies the impedance array matching parameters.

[0059] 5. Repeat steps 2 to 4 until the main control circuit determines that the impedance array matching parameter configuration is complete.

[0060] The process of the adaptive operation phase is as follows:

[0061] 1. Calculate the expected sound source response curve based on the underwater power amplifier's transmitting power.

[0062] 2. Compare the expected sound source response curve with the sound source signal collected by the hydrophone and calculate the power deviation.

[0063] 3. The power deviation is combined with the impedance angle obtained by the impedance detection circuit to calculate the impedance matching state of the transducer, where the impedance angle is the dynamic parameter of the inner loop of the algorithm and the power deviation is the integral parameter of the outer loop of the algorithm.

[0064] 4. Monitor the impedance matching status of the transducer. When it exceeds the set limit, the impedance matching device will automatically complete the adaptive parameter adjustment during the signal transmission interval, thereby maximizing the working efficiency of the transducer without affecting the signal transmission status.

[0065] From the above specific description of the present invention, it can be seen that the present invention arranges the matching impedance parameters in an array form, performs multi-resonance point broadband matching, and expands the working bandwidth based on transducer tuning. The present invention can also automatically adjust the matching impedance in real time according to the algorithm to achieve maximum efficiency output of the transducer.

[0066] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention and are intended to be encompassed by the claims of the present invention.

Claims

1. An adaptive underwater low-frequency acoustic transducer impedance matching device, used in an underwater sound source system of a seabed observation network, comprising a configuration phase and an adaptive operation phase, characterized in that: The device includes: a main control circuit, an impedance array circuit, an impedance detection circuit and an impedance switching circuit, wherein: The main control circuit is configured to, during a configuration phase, confirm through communication that the underwater power amplifier is in a standby state, set the impedance matrix to an initial value; and then repeat the following steps until it is determined that the impedance array matching parameter configuration is complete. The repeated steps include: sending a sweep frequency signal within a set frequency range to the underwater power amplifier, calculating a corrected impedance matrix value based on electrical signals at each frequency point collected by the impedance detection circuit, and modifying the impedance array matching parameters; It is also used to calculate the expected sound source response curve according to the signaling power of the underwater power amplifier during the adaptive operation phase, obtain the power deviation based on the sound source signal collected by the hydrophone, calculate the impedance angle according to the electrical signal collected by the impedance detection circuit, and then modify the impedance matching according to the power deviation and the impedance angle; including: Based on the transmitted power P1 of the underwater power amplifier, the transmitted power P2 collected and calculated by the impedance detection circuit, and the received power P3 collected by the hydrophone, the power deviation ΔP is obtained by the following formula: ΔP=k1*(P1-P2)+k2*(P2-P3) Among them, k1 and k2 are calibration coefficients; The impedance parameters are closed-loop controlled according to the power deviation ΔP and the impedance angle θ, thereby completing the modification of the impedance matching; The impedance array circuit is used to adopt a multi-resonance point broadband matching scheme to realize a circuit with different adjustable inductance and capacitance parameters by connecting multiple groups of inductors and capacitors in series and parallel, and to connect specific circuits according to the impedance switching circuit to achieve maximum power output for the underwater acoustic transducer; The impedance detection circuit is used to collect electrical signals of the impedance array circuit at various frequencies during the configuration phase and transmit them to the main control circuit; and is also used to collect electrical signals of the transmission frequency points during the adaptive operation phase and transmit them to the main control circuit; The impedance switching circuit is used to selectively connect the capacitors and inductors in the impedance array circuit through relays according to the matching impedance calculated by the main control circuit.

2. The adaptive underwater low-frequency acoustic transducer impedance matching device according to claim 1, characterized in that: The device is deployed between the underwater power amplifier and the underwater acoustic transducer, or integrated into the underwater power amplifier, and its external interfaces include: a power input interface and a communication interface connected to the underwater power amplifier, and a power output interface connected to the underwater acoustic transducer.

3. The adaptive underwater low-frequency acoustic transducer impedance matching device according to claim 1, characterized in that: The main control circuit is implemented based on MCU, DSP or FPGA chip.

4. The adaptive underwater low-frequency acoustic transducer impedance matching device according to claim 1, characterized in that: In the main control circuit, impedance matching calculation is performed based on the electrical signals of each frequency point collected by the impedance detection circuit; including: The power input port voltage signal, power input port current signal, power output port voltage signal and power output port current signal collected by the impedance detection circuit are used to calculate the real-time impedance Z, transmission power P2 and impedance angle θ according to the pulse IV measurement method.

5. The adaptive underwater low-frequency acoustic transducer impedance matching device according to claim 1, characterized in that: The impedance array circuit includes two groups of inductors and two groups of capacitors, wherein the first group of inductors is connected in series, the second group of inductors is connected in series, the first group of capacitors is connected in parallel, and the second group of capacitors is connected in parallel. The overall connection of the impedance array circuit is that the first group of inductors is connected in series with the first group of capacitors and then the second group of capacitors and the second group of inductors are connected in parallel.

6. The adaptive underwater low-frequency acoustic transducer impedance matching device according to claim 1, characterized in that: The impedance detection circuit uses a Hall sensor to collect signals.

7. The adaptive underwater low-frequency acoustic transducer impedance matching device according to claim 1, characterized in that: The configuration phase includes the following steps: Step 1) When the main control circuit confirms through communication that the underwater power amplifier is in a standby state, the impedance matrix is ​​set to an initial value; Step 2) The main control circuit provides a set of sweep frequency signals within a set frequency range to the underwater power amplifier, including the sweep frequency bandwidth, frequency point interval, number of single frequency point transmission groups, and number of transmission cycles per group; Step 3) The underwater power amplifier transmits in sequence according to the set information, and the impedance detection circuit collects the voltage and current signals of each frequency point and transmits them to the main control circuit; the main control circuit synchronously completes identification and records during the transmission of the underwater power amplifier; Step 4) After the signal is sent, the main control circuit calculates the corrected impedance matrix value based on the collected voltage and current signals at each frequency point and modifies the impedance array matching parameters; Step 5) Repeat steps 2) to 4) until the main control circuit determines that the impedance array matching parameter configuration is complete. The impedance switching circuit selects and connects the capacitors and inductors in the impedance array circuit through the relay according to the parameters configured by the main control circuit to achieve maximum power output of the underwater acoustic transducer.

8. The adaptive underwater low-frequency acoustic transducer impedance matching device according to claim 1, characterized in that: The processing process of the adaptive operation phase includes: Step 1) The main control circuit calculates the expected sound source response curve according to the transmitting power of the underwater power amplifier; Step 2) The main control circuit compares the expected sound source response curve with the sound source signal collected by the hydrophone and calculates the power deviation; Step 3) The impedance detection circuit collects the impedance angle and transmits it to the main control circuit; Step 4) The main control circuit converts the current and voltage signals obtained by the impedance detection circuit into an impedance angle, and combines the power deviation with the impedance angle to calculate the impedance matching state of the transducer, where the impedance angle is a dynamic parameter of the outer loop of the algorithm, and the power deviation is an integral parameter of the inner loop of the algorithm; Step 5) The main control circuit monitors the impedance matching status of the transducer. When it exceeds the set limit, the device autonomously completes the adaptive parameter adjustment during the signal transmission interval, thereby maximizing the working efficiency of the underwater acoustic transducer without affecting the signal transmission status.

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