An adaptive broadband matching control method and device for electroacoustic transducers

Abstract

This invention provides an adaptive broadband matching control method and apparatus for an electroacoustic transducer. The adaptive broadband matching control method for the electroacoustic transducer includes: constructing a closed-loop control system, I ac_ref (s) After passing through the proportional controller, the feedforward voltage reference value is obtained; I ac_ref (s) minus I ac The current error signal ΔI obtained after (s) ac The result obtained after passing through the PR controller is added to the feedforward voltage reference value, and the result is output as a signal wave to the PWM modulation module. The output terminal of the PWM modulation module is electrically connected to the control terminal of the switching transistor of the single-phase full-bridge inverter (30). The method also includes: dividing the working frequency band of the electroacoustic transducer into n sub-frequency bands. If the angular frequency is determined to belong to a certain sub-frequency band, the parameters of the PR controller are adjusted to the parameters of the PR controller corresponding to that sub-frequency band. Matrix M1, M2, ..., M n Different from each other.

Description

Technical Field

[0001] This invention relates to the fields of power electronics and underwater acoustic communication, and to a method for realizing high-power adaptive active impedance matching control over a wide bandwidth in a switch-type non-Foster system. Background Technology

[0002] Acoustic signals, as the only known signal suitable for long-distance transmission in water, are widely used in underwater surveying, seabed energy exploration, and military fields. Electroacoustic transducers, a crucial component in deep-sea communication, primarily convert electrical signals into acoustic signals. To better adapt to the complex underwater environment, the bandwidth requirements for electroacoustic transducers are constantly increasing, necessitating improvements in their performance to meet the demands for broadband acoustic signals. To satisfy the broadband and high-power requirements of electroacoustic transducers, in addition to using higher-performance materials, broadband matching control is also necessary.

[0003] Broadband matching achieves optimal impedance matching by designing a broadband impedance matching network at the transducer's front end. This network matches the transducer's impedance to the designed network, enabling the system to exhibit purely resistive behavior within the operating frequency range, reducing reactive power consumption, and increasing the transducer's active power output. Traditional passive impedance matching networks, which design LC networks between the power amplifier and the transducer, only achieve optimal impedance matching near a fixed frequency when the network is simple, failing to achieve broadband matching. Furthermore, using this method for broadband matching requires introducing numerous LC components, and determining the parameters of each component is extremely difficult, making the design process very complex.

[0004] In recent years, in the field of wireless communication, some scholars have proposed using active impedance matching networks (implemented by active devices) to construct negative impedance transformers, thereby achieving impedance matching. Existing research shows that compared to passive impedance matching networks, this method can effectively match nonlinear impedances and improve its performance. However, in the aforementioned active impedance matching networks, impedance matching is only applicable within a certain frequency band, thus achieving good impedance matching only within that band. For devices such as electroacoustic transducers, operation over a wide frequency band is typically required to improve their detection performance. Therefore, when existing active impedance matching networks are applied to electroacoustic transducers, they can only achieve good impedance matching within a certain frequency band, failing to meet the wide-bandwidth operation requirements of electroacoustic transducers. Summary of the Invention

[0005] This invention addresses the limitation of existing active impedance matching networks in meeting the requirements of electroacoustic transducers operating over a wide frequency range by providing an adaptive broadband matching control method and apparatus for electroacoustic transducers.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: an adaptive broadband matching control method for an electroacoustic transducer, wherein the driving signal of the electroacoustic transducer is provided by a power amplifier;

[0007] The feature is that the driving end of the electroacoustic transducer is connected to a single-phase full-bridge inverter; two switching transistors of the single-phase full-bridge inverter have a first common connection terminal, and the other two switching transistors have a second common connection terminal; the two input terminals of the single-phase full-bridge inverter are respectively electrically connected to the two output terminals of the DC power supply module; the first common connection terminal is electrically connected to one end of the first inductor, and the second common connection terminal, one end of the first capacitor, and one driving end of the electroacoustic transducer are electrically connected to each other; the other end of the first inductor, the other end of the first capacitor, and one output terminal of the power amplifier are electrically connected to each other at the first electrical connection point, and the other output terminal of the power amplifier and the other driving end of the electroacoustic transducer are electrically connected to each other;

[0008] The adaptive broadband matching control method for the electroacoustic transducer includes: constructing a closed-loop control system, wherein the output current reference value... Expressions in the s domain for , where s represents the variable of the s-domain function; This is an expression in the s-domain for the difference between the measured voltage at one end of the first capacitor and the voltage at the other end. The impedance being compensated in the lumped parameter model of the electroacoustic transducer Expressions in the s domain, The measured value of the power amplifier output current. Expressions in the s-domain; The feedforward voltage reference value is obtained after passing through the proportional controller. ; minus The current error signal was then obtained. Current error signal The result obtained after passing through the PR controller is compared with the feedforward voltage reference value. The sum is then output as a signal wave to the PWM modulation module, and the output terminal of the PWM modulation module is electrically connected to the control terminal of the single-phase full-bridge inverter switching transistor.

[0009] The adaptive broadband matching control method for the electroacoustic transducer further includes: dividing the operating frequency band of the electroacoustic transducer into n sub-frequency bands. If determining angular frequency If it belongs to a certain sub-frequency band, then the parameters of the PR controller are adjusted to the parameters of the PR controller corresponding to that sub-frequency band;

[0010] Among them, angular frequency The expression is fs The frequency of the output voltage signal of the power amplifier, matrix They are different. ; Let i = 1, 2, ..., n, and let i = 1, 2, ..., n, respectively, be the proportional coefficient and integral coefficient of the PR controller corresponding to the i-th sub-band.

[0011] In this invention, through the above-described configuration, the operating frequency band of the electroacoustic transducer is divided into n sub-bands, and the matrix formed by the proportional coefficient and integral coefficient of the PR controller corresponding to each i-th sub-band... The different sub-bands allow each PR controller to achieve good tracking performance of the AC signal near its corresponding resonant frequency, enabling the broadband matching control method of this invention to be applied to the wide bandwidth of the power amplifier, exhibiting good performance across all frequency ranges. Each sub-band's corresponding PR controller has a very large gain near its resonant frequency, achieving zero steady-state error regulation of the inverter output and good tracking of sinusoidal signals. Within the entire operating frequency band of the electroacoustic transducer composed of various sub-bands, there can be n resonant frequencies corresponding to the number of sub-bands (n), thus enabling control over the entire operating frequency band of the electroacoustic transducer. The control method of this invention can track the compensated impedance, providing a more accurate negative reactance value. Since it avoids canceling the equivalent reactance only at a single frequency, it is suitable for broadband matching of electroacoustic transducers. In this invention, the modulation feedback is calculated by subtracting the target matching value from the measured value, thereby achieving closed-loop control and higher control accuracy.

[0012] In the above technical solution, the first sub-frequency band, the second sub-frequency band, ..., the nth sub-frequency band are respectively The transfer function of the PR controller corresponding to the i-th sub-band in the s domain is:

[0013] ;

[0014] in, These are the proportional and integral coefficients of the PR controller corresponding to the i-th sub-band, respectively. This is the cutoff angular frequency of the PR controller. The resonant angular frequency of the PR controller corresponding to the i-th sub-band. The parameters that constitute the PR controller corresponding to the i-th sub-band.

[0015] In the above technical solution, The value satisfies the first and second conditions;

[0016] The first condition is: All are positive numbers;

[0017] in:

[0018] ;

[0019] proportionality coefficient k pwm It is the transfer function from the input of the PWM module to the output of the inverter bridge of the single-phase full-bridge inverter;

[0020] The second condition is: steady-state error. Not greater than a preset error threshold; where: , This is the reference value for the output current. This is the measured value of the power amplifier output current. This is the inductance value of the first inductor.

[0021] In this invention, through the above-described settings, all parameters of the PR controller corresponding to the i-th sub-frequency band can meet the requirements, achieving a smaller steady-state error. Therefore, the broadband matching control method of this invention can be applied to the wide bandwidth of power amplifiers, exhibiting good performance across all frequency ranges.

[0022] In the above technical solution, , , The value range is [15π, 25π] rad / s. The value range is [15, 30] rad / s.

[0023] In the above technical solution, It is a constant value.

[0024] In the above technical solution, =20πrad / s.

[0025] In the above technical solution, the proportional coefficient k of the proportional controller f The value range is [1, 5].

[0026] In the above technical solution, the input impedance of the electroacoustic transducer is inductive, and the lumped parameter model of the electroacoustic transducer includes a first static equivalent resistance connected in series between the two driving terminals of the electroacoustic transducer, a nonlinear inductance model, a nonlinear resistance model, and a first vibration system equivalent circuit structure. The inductance value of the nonlinear inductance model is... The resistance value of the nonlinear resistance model is , .

[0027] The control method of this invention can track the nonlinear impedance of the transducer (i.e., the nonlinear inductance and nonlinear resistance components in the inductance model), providing a more accurate negative reactance value, as it avoids canceling the equivalent reactance only at a single frequency. In a preferred embodiment, the nonlinear inductance model and the nonlinear resistance model are connected in series to form an eddy current impedance model, and the inductance value of the nonlinear inductance model... Resistance value of nonlinear resistance model The expression is:

[0028]

[0029] in, L is the first phase angle value. ex Here, p is the proportionality coefficient, q is the first coefficient, and q is the second coefficient. , .

[0030] In the above technical solution, the equivalent circuit structure of the first vibration system consists of an equivalent resistor, an equivalent inductor, and an equivalent capacitor connected in parallel.

[0031] In the above technical solution, the inductance value L of the first inductor s The capacitance value C of the first capacitor s Satisfy the following formula:

[0032] ;

[0033] in, These are the inductance value of the first inductor and the capacitance value of the first capacitor, respectively; F n F is the resonant frequency of the LC filter composed of the first inductor and the first capacitor; p Δi is the switching frequency of the switching transistors in the single-phase full-bridge inverter. ac_max It is 30% of the effective value of the rated output current of the power amplifier.

[0034] The present invention also provides an adaptive broadband matching control device for an electroacoustic transducer, comprising a processor configured to execute the adaptive broadband matching control method for an electroacoustic transducer as described in any of the preceding claims.

[0035] Compared with the prior art, the present invention has the following advantages:

[0036] 1. The improved PR control method proposed in this invention not only retains the good tracking performance of the PR controller for AC signals near the resonant frequency, but also divides the operating frequency band of the electroacoustic transducer into several sub-frequency bands suitable for the PR controller, thereby enabling the PR controller to be applied to a wide frequency range. This allows the matching control method using the PR controller to have good performance over a wide frequency range.

[0037] 2. The impedance matching method for adaptive wideband PR control proposed in this invention obtains the output voltage frequency of the power amplifier through a capture module in the control loop, and uses this frequency to adjust the relevant parameters of the PR controller, thereby realizing the adaptive adjustment of the PR controller parameters. This impedance matching method enables the non-Foster circuit to achieve better impedance tracking control in the wideband range of the electroacoustic transducer.

[0038] 3. This invention, based on the active impedance matching theory of non-Foster circuits, creatively proposes a non-Foster system suitable for high-power scenarios using power devices. The proposed non-Foster circuit can effectively perform broadband impedance matching for electroacoustic transducers, greatly expanding the power range of non-Foster circuit applications and providing new research ideas for related fields.

[0039] 4. The adaptive broadband impedance matching control method and device proposed in this invention utilizes a non-Foster circuit in a closed-loop control system to perform impedance matching on the electroacoustic transducer, and simultaneously employs an adaptive broadband PR control method, which can quickly and accurately match the nonlinear impedance present in devices such as electroacoustic transducers over a wide bandwidth. Attached Figure Description

[0040] Figure 1 This is a circuit diagram of the broadband adaptive impedance matching control device according to an embodiment of the present invention;

[0041] Figure 2 This is a block diagram of the adaptive broadband matching control device for an electroacoustic transducer in a non-Foster system according to an embodiment of the present invention.

[0042] Figure 3 This is a flowchart of the adaptive broadband matching control method for an electroacoustic transducer according to an embodiment of the present invention;

[0043] Figure 4 This is a diagram showing the relationship between the resonant frequency and fundamental frequency of each sub-band in an embodiment of the present invention.

[0044] Figure 5 This is a control block diagram of the broadband adaptive impedance matching control device according to an embodiment of the present invention;

[0045] Figure 6 A schematic diagram illustrating the acquisition of the frequency of the power amplifier's output voltage;

[0046] Figure 7 A comparison graph showing the change of the real part of the impedance of the electroacoustic transducer with frequency before and after matching using the method of the present invention.

[0047] Figure 8 A comparison graph showing the change of the imaginary part of the impedance of the electroacoustic transducer with frequency before and after matching using the method of the present invention.

[0048] Figure 9 A schematic diagram of the real part of the impedance for impedance matching of an electroacoustic transducer using the adaptive broadband impedance matching control method for non-Foster systems proposed in this invention.

[0049] Figure 10 This diagram illustrates the imaginary part of the impedance when using a traditional fixed-parameter PR controller for impedance matching control.

[0050] Figures 11(a), 11(b), 11(c), and 11(d) are schematic diagrams of the control block diagrams of embodiments of the present invention, which are simplified sequentially. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the implementation methods of the present invention will be described below with reference to the accompanying drawings and specific embodiments, providing a clear and complete description of the technical solutions of the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0052] To achieve optimal wideband control in impedance matching devices for electroacoustic transducers based on non-Foster circuits, a corresponding broadband matching control method needs to be designed. Compared to PI controllers, PR controllers have significantly higher gain near the resonant frequency, enabling zero steady-state error regulation of the inverter output and excellent tracking of sinusoidal signals. This invention proposes an adaptive broadband PR control impedance matching method based on traditional PR control, capable of real-time and accurate tracking of sinusoidal signals at any frequency, thus achieving adaptive broadband impedance matching control of the electroacoustic transducer.

[0053] This invention proposes an impedance matching control method and device for electroacoustic transducers based on a non-Foster system and adaptive broadband PR control. The PR controller has very high gain near the resonant frequency, enabling zero steady-state error regulation of the inverter output and good tracking of sinusoidal signals. However, this also means that traditional PR control methods cannot achieve regulation over a wide frequency range. The adaptive control system, composed of an improved PR controller and a feedforward element, solves this problem, enabling adaptive broadband impedance matching control of the system's electroacoustic transducers. Finally, simulation examples verify the rationality and effectiveness of the proposed adaptive broadband impedance matching control method and device.

[0054] This invention addresses the impedance matching problems of existing electroacoustic transducers by proposing an adaptive broadband matching control method and device for electroacoustic transducers based on a non-Foster system. The non-Foster circuit utilizes active devices to construct a negative impedance transformer, thereby achieving impedance matching and effectively solving the problems of complex passive impedance matching structures and the inability to accurately match nonlinear impedances. To further improve the performance of electroacoustic transducers and enable them to operate over a wide frequency range, this invention proposes an adaptive broadband PR control method for electroacoustic transducers. Existing PR controllers only exhibit good tracking control performance near a single frequency point. This invention uses a digital signal processor (DSP) to process and control the PR controller parameters, enabling the impedance matching device to achieve real-time and accurate matching of the nonlinear impedance of the electroacoustic transducer at any frequency. Compared to other control strategies, the DSP-based broadband control method proposed in this invention effectively retains the advantages of traditional PR controllers. Furthermore, the control of digital signals makes parameter adjustment of the PR controller easier, allowing for rapid and adaptive control of the PR controller parameters through feedback adjustment.

[0055] First, the output voltage frequency of the power amplifier is tracked in real time without error. Simultaneously, the adaptive control module adjusts the PR controller parameters (resonant angular frequency) based on this frequency signal. proportionality coefficient k p,i resonance coefficient k r,i This method performs rapid and accurate matching, and uses the PR controller and feedforward controller under these parameters to adjust the output pulse of the PWM module, thereby driving a single-phase full-bridge inverter to match the nonlinear impedance in the electroacoustic transducer. This method can perform real-time and accurate matching of the nonlinear impedance in electroacoustic transducers operating at any frequency, effectively solving the problems existing in current broadband matching research.

[0056] The present invention provides an adaptive broadband matching control method for an electroacoustic transducer, wherein the driving signal for the electroacoustic transducer 100 is provided by a power amplifier 20.

[0057] The electroacoustic transducer 100 is connected to a single-phase full-bridge inverter 30 at its drive end. Two switching transistors of the single-phase full-bridge inverter 30 have a first common connection terminal A, and the other two switching transistors have a second common connection terminal B. The two input terminals of the single-phase full-bridge inverter 30 are electrically connected to the two output terminals of the DC power supply module 4, respectively. The first common connection terminal A is electrically connected to one end of the first inductor 2, and the second common connection terminal B, one end of the first capacitor 1, and one drive end of the electroacoustic transducer 100 are electrically connected to each other. The other end of the first inductor 2, the other end of the first capacitor 1, and one output terminal of the power amplifier 20 are electrically connected to a first electrical connection point P1. The other output terminal of the power amplifier 20 and the other drive end of the electroacoustic transducer 100 are electrically connected to each other.

[0058] The adaptive broadband matching control method for the electroacoustic transducer includes: constructing a closed-loop control system, wherein the output current reference value... Expressions in the s domain for , where s represents the variable of the s-domain function; This is an expression in the s-domain for the difference between the voltage at one end and the voltage at the other end of the first capacitor 1, as measured. The impedance being compensated in the lumped parameter model of the electroacoustic transducer 100 Expressions in the s domain, The measured output current of power amplifier 20 Expressions in the s-domain; The feedforward voltage reference value is obtained after passing through the proportional controller. ; minus The current error signal was then obtained. Current error signal The result obtained after passing through the PR controller is compared with the feedforward voltage reference value. The sum is then output as a signal wave to the PWM modulation module, and the output terminal of the PWM modulation module is electrically connected to the control terminal of the 30 switching transistor of the single-phase full-bridge inverter.

[0059] The adaptive broadband matching control method for the electroacoustic transducer further includes: dividing the operating frequency band of the electroacoustic transducer into n sub-frequency bands. If determining angular frequency If it belongs to a certain sub-frequency band, then the parameters of the PR controller are adjusted to the parameters of the PR controller corresponding to that sub-frequency band;

[0060] in, fs The frequency of the output voltage signal of the power amplifier 20, matrix They are different. .

[0061] Let i = 1, 2, ..., n, and let i = 1, 2, ..., n, respectively, be the proportional coefficient and integral coefficient of the PR controller corresponding to the i-th sub-band.

[0062] The first sub-band, the second sub-band, ..., the nth sub-band are respectively The transfer function of the PR controller corresponding to the i-th sub-band in the s domain is:

[0063] ;

[0064] in, These are the proportional and integral coefficients of the PR controller corresponding to the i-th sub-band, respectively. This is the cutoff angular frequency of the PR controller. The resonant angular frequency of the PR controller corresponding to the i-th sub-band. The parameters that constitute the PR controller corresponding to the i-th sub-band.

[0065] The value of satisfies the first and second conditions.

[0066] The first condition is: All are positive numbers;

[0067] in:

[0068] ;

[0069] proportionality coefficient k pwm It is the transfer function from the input of the PWM module to the output of the inverter bridge of the single-phase full-bridge inverter 30.

[0070] The second condition is: steady-state error. Not greater than the preset error threshold. Wherein: , This is the reference value for the output current. This is the measured value of the power amplifier output current. This is the inductance value of the first inductor. (The rest of the text appears to be incomplete and possibly contains errors. When substituting the transfer function of the PR controller corresponding to the i-th sub-band in the s-domain, if the angular frequency... When taking any value within the sub-frequency band, the steady-state error If none of the parameters exceed the preset error threshold, then the parameters of the PR controller corresponding to the i-th sub-frequency band are... The second condition is met. The preset error threshold is preferably 0.2, i.e. If so, then the second condition is satisfied.

[0071] , , The value range is [15π, 25π] rad / s. The value range is [15, 30] rad / s. It is a constant value. =20πrad / s. The proportional coefficient k of the proportional controller. f The value range is [1, 5].

[0072] The input impedance of the electroacoustic transducer 100 is inductive. The lumped parameter model of the electroacoustic transducer 100 includes a first static equivalent resistance 57 connected in series between the two driving terminals of the electroacoustic transducer 100, a nonlinear inductance model 52, a nonlinear resistance model 51, and a first vibration system equivalent circuit structure V1. The inductance value of the nonlinear inductance model 52 is... The resistance value of the nonlinear resistance model 51 is... , .

[0073] It should be noted that the scheme protected in this application is not limited to schemes where the input impedance of the electroacoustic transducer 100 is inductive, or based on nonlinear inductor model 52 and nonlinear resistor model 51. Those skilled in the art can determine the impedance to be compensated based on actual needs, thereby determining the impedance to be compensated. The expression.

[0074] The nonlinear inductor model 52 and the nonlinear resistor model 51 are connected in series to form an eddy current impedance model, and the inductance value of the nonlinear inductor model 52 is... Resistance value of nonlinear resistance model 51 The expression is:

[0075]

[0076] in, L is the first phase angle value. ex Here, p is the proportionality coefficient, q is the first coefficient, and q is the second coefficient. , .

[0077] The first vibration system equivalent circuit structure V1 consists of the first vibration system equivalent resistor 53, the first vibration system equivalent inductor 54, and the first vibration system equivalent capacitor 55 connected in parallel.

[0078] The inductance value L of the first inductor 2 s The capacitance value C of the first capacitor 1 s Satisfy the following formula:

[0079] ;

[0080] in, These are the inductance value of the first inductor and the capacitance value of the first capacitor, respectively; F n F is the resonant frequency of the LC filter formed by the first inductor 2 and the first capacitor 1; p Δi is the switching frequency of the switching transistors in the single-phase full-bridge inverter 30. ac_max It is 30% of the effective value of the rated output current of the power amplifier 20.

[0081] The present invention also provides an adaptive broadband matching control device for an electroacoustic transducer, including a processor configured to execute the aforementioned adaptive broadband matching control method for an electroacoustic transducer.

[0082] Compared to passive impedance matching methods, active impedance matching offers faster response times, higher accuracy, and smaller size. The schematic diagram of the broadband adaptive impedance matching control device based on a non-Foster system proposed in this invention is shown below. Figure 1 As shown, the device comprises a power supply (power amplifier), a non-Foster matching system, and a high-power electroacoustic emitting device (electroacoustic transducer). The power supply is the power amplifier 20, and the high-power electroacoustic emitting device is the electroacoustic transducer 100. The non-Foster matching circuit 200 includes an AC-side first capacitor 1 and a first inductor 2, a DC-side capacitor 3 and a DC-side power supply 4, and a single-phase full-bridge inverter 30. One output terminal of the power amplifier 20 is directly electrically connected to one drive terminal of the electroacoustic transducer 100, and the other output terminal of the power amplifier 20 is electrically connected to one end of the first capacitor 1. The other end of the first capacitor 1 is electrically connected to the other drive terminal of the electroacoustic transducer 100. The two output terminals of the DC-side power supply 4 are respectively electrically connected to the corresponding input terminals of the single-phase full-bridge inverter 30, and the DC-side capacitor 3 is connected in parallel with the DC-side power supply 4. The two bridge arms of the single-phase full-bridge inverter 30 have two common connection terminals, with two switching transistors having a first common connection terminal A and the other two switching transistors having a second common connection terminal B. The first common connection terminal A is electrically connected to one end of the first inductor 2, and the other end of the first inductor 2 is electrically connected to the P1 connection point. The second common connection terminal B is directly electrically connected to the P2 connection point.

[0083] In the adaptive broadband matching control device for the electroacoustic transducer in the non-Foster system, the electroacoustic transducer has a lumped parameter model: the lumped parameter model includes the first static resistance R at the electrical terminal. e First equivalent inductance L em And the mechanical end first vibration equivalent circuit. First static equivalent resistance R e First equivalent inductance L emIt is connected in series with the first vibration equivalent circuit, and the first equivalent inductance L em Nonlinear resistor With nonlinear inductors The eddy current impedance model is composed of series connections; the first vibration equivalent circuit consists of the equivalent resistance R of the first vibration system. mes The equivalent capacitance C of the first vibration system mes The equivalent inductance L of the first vibration system mes They are connected in parallel.

[0084] The calculation method of the lumped parameter model is as follows: First, the first equivalent inductance is equivalent to a static inductance. By applying an excitation signal to the driving end of the electroacoustic transducer, the input admittance curve / input impedance curve of the electroacoustic transducer is obtained. Then, the first static equivalent resistance R of the electroacoustic transducer is identified using the obtained input admittance curve / input impedance curve. e Equivalent circuit to the first vibration system. The resistance value of the equivalent resistor 53 of the first vibration system, the inductance value of the equivalent inductor 54 of the first vibration system, and the capacitance value of the equivalent capacitor 55 of the first vibration system are obtained based on the electrical input admittance curve / electrical input impedance curve.

[0085] In the adaptive broadband matching control device for the electroacoustic transducer in the non-Foster system, in addition to the lumped parameter model of the electroacoustic transducer, a first inductor L is also included. s First capacitor C s With the second capacitor C dc First inductor L s First capacitor C s The value should meet the following conditions:

[0086]

[0087]

[0088] Among them, f n f is the resonant frequency of the LC filter circuit composed of the first inductor and the first capacitor; p This refers to the switching frequency of the switching transistors in a single-phase full-bridge inverter circuit. It is 0.3 times the effective value of the rated output current of the power amplifier; This is the output voltage of the DC power supply module connected to the DC side of the single-phase inverter. Based on theoretical calculations and margin considerations, the filter inductor L is selected. s The filter capacitor C is 2mH. s It is 10μF.

[0089] Figure 1The electroacoustic transducer model shown consists of a first equivalent inductance 56, a first static equivalent resistance 57, and a first vibration system equivalent circuit structure V1. The first vibration system equivalent circuit structure is formed by connecting a first vibration system equivalent resistance 53, a first vibration system equivalent inductance 54, and a first vibration system equivalent capacitance 55 in parallel. The two ends of the first vibration system equivalent circuit structure V1 are electrically connected to the other ends of the first static equivalent resistance 57 and the first equivalent inductance 56, respectively. The first equivalent inductance 56 is an eddy current impedance model formed by connecting a nonlinear resistance model 51 and a nonlinear inductance model 52 in series.

[0090] like Figure 1 As shown, the presence of inductive impedance in the electroacoustic transducer reduces its power factor. When the transducer is directly driven by a power amplifier, a large amount of reactive power is generated, while the resistor consumes some active power. Consequently, the active power input obtained by the transducer through the power amplifier cannot allow it to operate at its optimal state. Therefore, the non-Foster circuit proposed in this invention generates a negative impedance equal to the impedance value in the electroacoustic transducer within the power loop formed by the power amplifier and the transducer. This negative impedance cancels out the transducer's impedance, thereby improving its power factor and increasing its operating efficiency.

[0091] The block diagram of the adaptive broadband matching control device for electroacoustic transducers in non-Foster systems is as follows: Figure 2 As shown, the device includes a signal acquisition module, an equivalent model of an electroacoustic transducer, and an adaptive control system. Figure 3 The flowchart of the proposed control method is shown below, combined with... Figure 2 and Figure 3 The signal acquisition module includes a voltage detection module, a voltage zero-crossing comparator module, a pulse capture module, and a current detection module: the voltage detection module and the current detection module acquire the voltage and current of the power amplifier, respectively; the voltage zero-crossing comparator compares the voltage u acquired by the voltage detection module. acCompared to zero voltage, a high-level output is generated when the voltage is greater than zero, and a low-level output is generated when the voltage is less than zero, thus converting the voltage into a square wave signal. The pulse capture module captures the trigger edges of the square wave signal to obtain the trigger time of each trigger edge, from which the frequency of the power amplifier's output voltage can be calculated. The equivalent model of the electroacoustic transducer includes the electrical input admittance / impedance curve and the lumped parameter model: the electrical input admittance / impedance curve is obtained by applying excitation to the electroacoustic transducer terminals; then, the static parameters are obtained using this curve; finally, the coefficients of the nonlinear resistance and nonlinear inductance in the lumped parameters are obtained by fitting and solving, thus obtaining the values ​​of the nonlinear resistance and nonlinear inductance, thereby obtaining the lumped parameter model. The adaptive control system includes an error calculation module, a reference current calculation module, a feedforward controller, an adaptive control module, a PR controller, a PWM modulation module, and a single-phase full-bridge inverter. The reference current is calculated based on the nonlinear inductance and nonlinear resistance in the lumped parameter model. The internal unbalanced current is obtained by subtracting the reference current from the power amplifier output current obtained from the current detection module through the error calculation module. The feedforward controller converts the reference current into a feedforward voltage reference value. The adaptive control module uses the power amplifier output voltage frequency to match the resonant angular frequency, proportional coefficient, and resonant coefficient of the PR controller. The PR controller, constructed using the PR control parameters provided by the adaptive control module, converts the internal unbalanced current into an internal unbalanced voltage reference value. The PWM modulation module adds the feedforward voltage reference value and the internal unbalanced voltage reference value, then performs calculations with a carrier wave to obtain a PWM modulation wave. The single-phase full-bridge inverter uses the PWM wave to control the switching transistors to turn on and off, outputting the required AC voltage.

[0092] The steps for broadband matching of an electroacoustic transducer using the transducer broadband adaptive impedance matching control method for non-Foster systems proposed in this invention are as follows:

[0093] The non-Foster broadband adaptive impedance matching control method includes: establishing a control system based on a PR controller and a capture module (CAP), including the following steps: Step S1: First, the first equivalent inductance is equivalent to a static inductance L. em By applying an excitation signal to the driving end of the electroacoustic transducer, the input admittance / input impedance curve of the electroacoustic transducer is obtained. Then, the first static equivalent resistance R of the electroacoustic transducer is identified using the obtained input admittance / input impedance curve. e Equivalent circuit to the first vibration. Finally, the nonlinear resistance of the lumped parameter model. With nonlinear inductors The corresponding coefficients are obtained by fitting the solution. Existing studies have already conducted relatively complete analyses of them, so they will not be elaborated here.

[0094] In step S1, the specific solution method for each static parameter in the lumped parameter model is as follows:

[0095] Step S101: Given the driving signal frequency f s Since the Hz is 0, analysis shows that at the initial time 0, only the first static equivalent resistance 57 exists in the lumped parameter model. Therefore, the value of the impedance curve at time 0 is the resistance value of the first static equivalent resistance 57.

[0096] Step S102: When the equivalent inductance 54 and the equivalent capacitance 55 of the first vibration system in the circuit resonate in series, the equivalent reactance of the circuit is the static inductance L. em The sensitivity value. Therefore, the driving signal frequency. At this point, the reactance value corresponding to the obtained impedance curve is L. em .

[0097] Step S103: When the equivalent inductance 54 and equivalent capacitance 55 of the first vibration system in the circuit are equal to the static inductance L... em When parallel resonance occurs, the circuit reactance is zero, and the circuit's equivalent resistance is the sum of the resistances of the first static equivalent resistance 57 and the first vibration system equivalent resistance 53. Therefore, given the driving signal frequency... At this time, the resistance value of the first static equivalent resistance 57 can be obtained by subtracting the resistance value of the impedance curve obtained at this time from the resistance value of the first static equivalent resistance 57.

[0098] Step S2: Obtain the reference current signal I through calculation. ac_ref The current output by the power amplifier is used as the feedback signal I. ac The loop error is obtained by subtracting the feedback signal from the reference signal. ;

[0099] As can be seen from the lumped parameter model, the presence of nonlinear resistance and nonlinear inductance weakens the efficiency of the electroacoustic transducer. The non-Foster circuit proposed in this invention can effectively match this negative impedance, thereby maximizing the output efficiency of the electroacoustic transducer. Figure 1 It can be seen that the proposed non-Foster circuit is connected to the main power circuit through the first capacitor 1, in order to match the nonlinear resistance and nonlinear inductance of the electroacoustic transducer. Therefore, it is necessary to induce a corresponding negative impedance across the first capacitor 1. Then the equivalent current generated by the equivalent negative impedance in the power circuit can be used as the reference signal of the control system.

[0100] Reference signal i ac_ref The calculation formula is:

[0101]

[0102] Where s is a complex variable in the complex field; This is the voltage difference between the other end of the first capacitor and one end of the first capacitor. The inductance value of the nonlinear inductor model Expressions in the complex field; The resistance value of the nonlinear resistance model Expressions in the complex field.

[0103] Figure 5 The control system for an electroacoustic transducer impedance matching control device using a non-Foster system and adaptive broadband PR control is described below:

[0104] Step S3: After the power amplifier output voltage passes through a voltage transformer, the input voltage comparator compares it with the reference voltage of zero to obtain a square wave signal, as shown in the schematic diagram below. Figure 6 As shown.

[0105] The obtained square wave signal is input into the capture module to obtain the pulse width of the square wave signal, which is then converted into the pulse frequency, i.e., the frequency f of the power amplifier output voltage. s ;

[0106] The frequency f of the power amplifier output voltage s The calculation formula is:

[0107]

[0108] Among them, t k+1 t k These are the trigger times of the previous pulse edge and the trigger times of the next pulse edge, respectively.

[0109] Step S4: Calculate the corresponding angular frequency using the power amplifier output voltage frequency obtained in step S3. The adaptive control module automatically and quickly matches the resonant angular frequency of the PR controller, as well as the values ​​of the proportional coefficient and the resonant coefficient.

[0110] In the control method, the transfer function of the PR controller is:

[0111]

[0112] Where, k p k is the proportional gain of the PR controller. r The resonant coefficient; This is the cutoff angular frequency. Its resonant angular frequency is... The gain at point is:

[0113]

[0114] As can be seen from the above equation, the PR controller at the resonant angular frequency The gain at point is determined by the scaling factor k p,i , resonance coefficient k r,i Decision. Cutoff angular frequency. The bandwidth of the controller can be adjusted as... As the value of increases, the control bandwidth of the controller increases, however The value of will affect the stability of the system; if its value is too large, the stability of the controller will deteriorate. Therefore, the PR controller can be adjusted at the resonant angular frequency. It maintains good tracking and control performance in the vicinity.

[0115] Figure 4 This is a schematic diagram of the adaptive broadband PR control method proposed in this invention. The adaptive control module of this invention processes and controls the PR controller parameters through a digital signal processor (DSP), enabling the impedance matching device to achieve real-time and accurate matching of the nonlinear impedance of the electroacoustic transducer at any frequency. The implementation process is as follows: According to the PR control principle and the above analysis, the PR controller has a very large gain near the resonant frequency, enabling zero steady-state error adjustment of the inverter output and excellent tracking of sinusoidal signals.

[0116] For the operating frequency band ω1~ω n+1 For electroacoustic transducers, traditional PR control methods can only maintain good performance within a small range of their operating frequency band. This invention divides the frequency band into n sub-bands, thus requiring only a reasonable division of the sub-band widths. Then, a suitable PR controller can be configured to achieve optimal control within the corresponding sub-band range.

[0117] Transfer function of PR controller in each sub-band As shown in the following formula:

[0118]

[0119]

[0120] in These are the proportional coefficient and resonant coefficient of the PR controller in the i-th sub-band, respectively; , Let be the starting and ending angular frequencies of the i-th sub-band, respectively. The resonant angular frequency of the PR controller in the i-th sub-band is... Cutoff angular frequency The bandwidth of the controller can be adjusted as... As the value of increases, the control bandwidth of the controller increases, however The value of will affect the stability of the system; if its value is too large, the stability of the controller will deteriorate. Therefore, the PR controller can only operate at the resonant angular frequency. While maintaining good tracking and control performance in the vicinity, it cannot be directly used in the broadband matching control of the electroacoustic transducer based on non-Foster circuits described in this invention.

[0121] To implement the aforementioned wideband PR control method, this invention employs a digital signal processor (DSP). This digital control method facilitates easier parameter adjustment of the PR controller, enabling rapid and adaptive control of the PR controller parameters through real-time feedback of the power amplifier voltage and frequency. The specific implementation steps are as follows:

[0122] Step S4.1: Determine the number of segments. As shown in the following formula, determining the number of segments n determines the width of the sub-band. This determines the stability of the PR controller. Based on the principle analysis of the PR controller, it can be seen that... A smaller value indicates better control performance of the PR controller for that frequency band. However, this also means more PR controller parameters need to be determined, increasing the design complexity and thus requiring a controller with an appropriate bandwidth. .

[0123]

[0124] Step S4.2, determine the controller coefficients. Based on the number of segments n determined in step 4.1 and the width of the sub-band... Then, the resonant angular frequency of the PR controller in each sub-band can be obtained according to the above formula. The PR controller for the i-th sub-band is as follows.

[0125]

[0126] The corresponding proportional coefficient of the PR controller With resonance coefficient The parameters can be determined using traditional PR controller parameter determination methods, combining theoretical calculations with experiments.

[0127] Step S4.3 involves mapping the bandwidth range of each sub-band from step 4.2 to the corresponding PR controller parameters in the digital signal processor (DSP). To ensure the PR controller can select the appropriate controller parameters for different system frequencies, a complete mapping is necessary. This allows for accurate real-time tracking of the sinusoidal signal at any frequency using a precise PR controller, achieving adaptive broadband impedance matching control of the electroacoustic transducer.

[0128] Step S4.4: Automatically select the corresponding PR controller based on the output voltage frequency of the power amplifier. This invention converts the PR controller into a digital quantity by discretizing it, facilitating real-time adjustment and control of its parameters in a digital signal processor (DSP). When the power amplifier output frequency is transmitted in real-time to the adaptive control module designed in this invention via the pulse capture unit, the adaptive control module matches the corresponding PR controller parameters to form a digital PR controller based on the current power amplifier output frequency.

[0129] Based on the resonant angular frequency of the PR controller in the i-th sub-band, the corresponding proportional coefficient and resonant coefficient of the PR controller for the corresponding sub-band can be obtained through a combination of theoretical calculations and experiments. The frequency band, corresponding proportional coefficient, and resonant coefficient of each sub-band are then placed in the adaptive control module. The adaptive control module matches the angular frequency of the power amplifier's output voltage to determine its frequency band, and then outputs the corresponding resonant angular frequency ω of the PR controller. 0,i proportionality coefficient k p,i With resonance coefficient k r,i .like Figure 4 As shown, for an electroacoustic transducer with an operating frequency band of 2π×200~2π×500 rad / s, the designed sub-bandwidth is 2π×20 rad / s. As can be seen from the figure, this is divided into 2π×200~2π×220 rad / s, 2π×220~2π×240 rad / s, and up to 2π×480~2π×500 rad / s. Within each sub-band, the PR controller parameters correspond to the frequency band variation. When the transducer's operating frequency switches between different frequency bands, the adaptive control module will automatically match the PR controller parameters corresponding to that frequency band.

[0130] Step S5: Convert the error signal obtained in step S4 into an error signal. The system unbalanced voltage reference value V is obtained through the PR controller. ac_ref As shown in the following formula.

[0131] The obtained reference signal is processed by a proportional controller to obtain the feedforward voltage reference value V. ac_f As shown in the following formula;

[0132]

[0133]

[0134] Step S6: The unbalanced voltage reference value V obtained in step S5 is... ac_ref Compared with the feedforward voltage reference value V obtained in step 6 ac_fThe summation is then input into the PWM module, which is electrically connected to the control terminal of the single-phase full-bridge inverter. Through pulse width modulation, the switching transistors of the single-phase full-bridge inverter are controlled to turn on and off, ultimately yielding the power amplifier output current I. ac .

[0135]

[0136]

[0137] Where, k pwm For PWM module equivalent parameters; k f L is the proportional coefficient of the feedforward element (i.e., the proportional controller); s C is the inductance value of the first inductor. s This is the capacitance value of the first capacitor.

[0138] The closed-loop transfer function of the non-Foster broadband adaptive impedance matching control method proposed in this invention is:

[0139]

[0140] Where G(s) is the transfer function of the PR controller; K pwm K represents the equivalent parameters of the PWM module. f L is the proportional coefficient of the feedforward circuit; s C is the inductance value of the first inductor. s This is the capacitance value of the first capacitor.

[0141] The parameter values ​​for each component in this case are shown in Table 1, including the nonlinear resistor. Values Nonlinear inductor Values .

[0142] Table 1. Circuit component parameter values

[0143]

[0144] Figure 7 and Figure 8 The results of matching the nonlinear resistor and nonlinear inductor in an electroacoustic transducer using the broadband matching method based on non-Foster circuits proposed in this invention are as follows: Figure 7 This represents the impedance real part matching case. Figure 8This describes the impedance imaginary part matching case. It can be seen that as the power amplifier output frequency increases, the values ​​of the nonlinear resistance and nonlinear reactance exhibit roughly the same trend. At lower frequencies, the resistance increases sharply from its initial value, reaches its maximum value, then decreases sharply to slightly greater than the initial value, and subsequently increases gradually with frequency. Similarly, at lower frequencies, the reactance first increases sharply from zero with frequency, reaches its maximum value, then decreases sharply to a negative value equal to the maximum value, then rises rapidly to zero and subsequently increases gradually with frequency. The real and imaginary parts of the matching negative impedance given by this invention both gradually increase with frequency. Figure 7 The curve obtained after matching using the adaptive impedance matching method for non-Foster electroacoustic transducers proposed in this invention shows that when the frequency is greater than 50Hz, good matching of the nonlinear resistance can be achieved, at which point only the static resistance remains in the system. Figure 8 It can be seen that the proposed method can also match the nonlinear inductance of the system well. After the nonlinear resistance and nonlinear inductance of the system are eliminated, the electroacoustic transducer can be guaranteed to have high output efficiency in a wide frequency range.

[0145] Figure 9 This is a schematic diagram of some key port outputs in the embodiment of the method proposed in this invention. The effective value of the power amplifier output voltage is a fixed value of 15V. The output frequencies are selected as 200Hz, 300Hz, 400Hz and 500Hz, respectively. That is, when the output frequency is in the range of [200Hz, 220Hz], (280Hz, 300Hz], (380Hz, 400Hz], (480Hz, 500Hz], the parameters of the PR controller at the corresponding frequencies are shown in Table 2. Using the non-Foster broadband adaptive impedance matching control method and device proposed in this invention, the output voltage of the non-Foster circuit, the output current of the power amplifier, the steady-state matching error and the nonlinear impedance matching of the electroacoustic transducer are as follows. Figure 9 As shown. The steady-state matching error is the loop error. The magnitude of the impedance matching value under steady-state conditions reflects the control system's ability to track the reference signal. Impedance matching, on the other hand, provides a direct view of the system's matching value to the nonlinear impedance in the electroacoustic transducer, facilitating a more detailed analysis of the impedance matching performance under the control system's influence.

[0146] Table 2 PR Controller Parameter Values

[0147]

[0148] Depend on Figure 9As can be seen, the proposed method achieves good impedance matching in the electroacoustic transducer. The steady-state error gradually decreases with increasing frequency, remaining below 0.04 at 500Hz. It exhibits a fast response speed, reaching the target value within approximately one cycle, and demonstrates small overshoot and good stability. The proposed method can achieve complete impedance matching at different frequencies quickly, with accurate and rapid switching between frequencies.

[0149] Figure 10 Using the values ​​in Table 2 at 200Hz as controller parameters, the output voltage of the non-Foster circuit, the output current of the power amplifier, the steady-state matching error, and the nonlinear impedance matching of the electroacoustic transducer were obtained after frequency conversion control at 200Hz, 300Hz, 400Hz, and 500Hz. Figure 10 It can be seen that when using a single-parameter PR controller, the system only exhibits good stability at 100Hz. As the frequency increases, the system's matching error gradually increases, and its impedance matching capability for the electroacoustic transducer deteriorates. This demonstrates the effectiveness and advancement of the electroacoustic transducer impedance matching control method and device based on a non-Foster system and adaptive broadband PR control proposed in this invention.

[0150] Without a matching network, the equivalent inductance of the transducer shares the power supplied by the power amplifier 20, resulting in lower output power of the transducer at multiple frequencies. The solution of this invention is to use a non-Foster matching network to adjust the equivalent admittance (impedance) at the transducer input position over a wider frequency range while maintaining a constant output voltage of the power amplifier 20, thereby increasing the transducer output power and achieving wideband output.

[0151] If a linear system is used to match the negative impedance, the static nonlinear inductor is not fully matched due to the influence of nonlinear factors such as eddy current effects. After introducing the control system described in this paper, the impedance formed by the nonlinear resistor and nonlinear inductor can be matched, thereby improving the output efficiency of the transducer and extending the output bandwidth of the high-power transducer. Based on the target matching value, the power amplifier output current is used as a reference value. Through feedback and feedforward control in the control system, the inverter output port characteristics are kept stable and exhibit a negative impedance, thus achieving accurate and rapid impedance broadband matching for the high-power electroacoustic transducer. This invention uses feedforward control to enhance the dynamic response speed of the control system, achieving precise and rapid control of the broadband matching system.

[0152] like Figure 1 As shown, the linear lumped parameter model of the high-power electroacoustic transducer is derived based on the motor analogy method, including the equivalent circuits of the drive system and the vibration system. The two systems are connected by a transformer with a turns ratio equal to the electromechanical conversion factor. The equivalent circuit of the drive system includes a series-connected static DC resistance R.e and static inductance L em The equivalent circuit of the vibration system is composed of dynamic inductance L m Dynamic capacitor C m Dynamic resistance R1 and load impedance Z L It is composed of series components. The lumped parameter model of high-power transmitters can also be simplified to a system consisting of a driving static DC resistor R. e and static inductance L em and the equivalent dynamic resistance R of the vibration system mes Equivalent dynamic inductance L of the vibration system mes The equivalent dynamic capacitance C of the vibration system mes The equivalent circuit of the five-parameter components.

[0153] Reference value of power amplifier output current Compared with the actual output current value After comparison, the difference between the two values ​​is adjusted by the PR controller, and the output of the PR controller is compared with the reference current feedforward value. The summation produces a signal wave, which is then used by an inverter to generate PWM pulses. These pulses control the operating state of the switching non-Foster matching system, ensuring that the output port characteristic of the matching network remains stable at -L. em (ω), thus achieving matching of the static reactance of the high-power electroacoustic transducer. The inverter bridge output voltage is The carrier wave is a triangular wave.

[0154] The power amplifier output current uses a PR controller for error-free tracking of the sinusoidal signal via feedback control, and a proportional controller is used for feedforward control to improve the system's dynamic response speed. The transfer functions of the two controllers are:

[0155] proportionality coefficient This is the transfer function from the input of the PWM module to the output of the inverter bridge of the single-phase full-bridge inverter 30. This scheme adjusts the waveform of the signal wave to regulate the drive signal of the control switching transistor, thereby adjusting the inverter output waveform. In this invention, the nonlinear impedance caused by eddy currents is matched.

[0156] As shown in Figures 11(a)-11(d), the transfer function expression of the closed-loop system can be derived as follows:

[0157]

[0158] Regarding the selection of relevant parameters, firstly, for the cutoff frequency... The main impact is on system bandwidth; in this example, we choose 15. Regarding the width of the segmented frequency, too large a width will affect the controller's tracking capability, while too small a width will result in an excessive number of segments (n), increasing the computational load and posing a challenge to the DSP's processing capabilities. Based on experimental results, when using the proposed method for broadband adaptive impedance matching of the transducer, a bandwidth of approximately 40π (20Hz) is preferable. Regarding the selection of PR controller parameters, such as... Figure 1 As shown, firstly, initial values ​​are obtained for the appropriate frequency band based on experience. Then, the stability of the determined initial values ​​is judged by substituting them into the Routh table. If the stability requirements are not met, the system is corrected and iterated until it is stable.

[0159] The corresponding characteristic equation is:

[0160]

[0161] in:

[0162]

[0163]

[0164]

[0165]

[0166] The stability of the system can then be analyzed based on the Routh criterion.

[0167]

[0168] If all elements in the first column are positive, then the system is stable.

[0169] The first column is .

[0170] In Figures 11(a)-11(d), G(s) corresponds to Figure 5 The transfer function of the PR controller.

[0171] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0172] The embodiments of the present invention have been described in detail above, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and modifications made within the scope of the present invention should still fall within the scope of the present invention. After reading this invention, those skilled in the art will understand that various equivalent modifications to the present invention fall within the scope defined by the appended claims. Unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

Claims

1. An adaptive broadband matching control method for an electroacoustic transducer, wherein the driving signal for the electroacoustic transducer (100) is provided by a power amplifier (20); Its features are, The electroacoustic transducer (100) is connected to a single-phase full-bridge inverter (30) at its drive end; the single-phase full-bridge inverter (30) has two switching transistors with a first common connection terminal (A) and two other switching transistors with a second common connection terminal (B); the two input terminals of the single-phase full-bridge inverter (30) are respectively electrically connected to the two output terminals of the DC power supply module (4); the first common connection terminal (A) is electrically connected to one end of the first inductor (2), and the second common connection terminal (B), one end of the first capacitor (1), and one drive end of the electroacoustic transducer (100) are electrically connected to each other; the other end of the first inductor (2), the other end of the first capacitor (1), and one output terminal of the power amplifier (20) are electrically connected to each other at the first electrical connection point (P1), and the other output terminal of the power amplifier (20) and the other drive end of the electroacoustic transducer (100) are electrically connected to each other; The adaptive broadband matching control method for the electroacoustic transducer includes: constructing a closed-loop control system, wherein... Output current reference value Expressions in the s domain for , where s represents the variable of the s-domain function; The expression for the difference between the voltage at one end and the voltage at the other end of the first capacitor (1) obtained by measurement in the s-domain is given. The impedance being compensated in the lumped parameter model of the electroacoustic transducer (100) Expressions in the s domain, The measured value of the output current of the power amplifier (20) Expressions in the s-domain; The feedforward voltage reference value is obtained after passing through the proportional controller. ; minus The current error signal was then obtained. Current error signal The result obtained after passing through the PR controller is compared with the feedforward voltage reference value. The sum is output as a signal wave to the PWM modulation module. The output terminal of the PWM modulation module is electrically connected to the control terminal of the switching transistor of the single-phase full-bridge inverter (30). The adaptive broadband matching control method for the electroacoustic transducer further includes: dividing the operating frequency band of the electroacoustic transducer into n sub-frequency bands. If determining angular frequency If it belongs to a certain sub-frequency band, then the parameters of the PR controller are adjusted to the parameters of the PR controller corresponding to that sub-frequency band; in, f s The frequency of the output voltage signal of the power amplifier (20), matrix They are different. ; Let i = 1, 2, ..., n, and let i = 1, 2, ..., n, respectively, be the proportional coefficient and integral coefficient of the PR controller corresponding to the i-th sub-band.

2. The adaptive broadband matching control method for electroacoustic transducers according to claim 1, characterized in that: The first sub-band, the second sub-band, ..., the nth sub-band are respectively The transfer function of the PR controller corresponding to the i-th sub-band in the s domain. for: ； in, These are the proportional and integral coefficients of the PR controller corresponding to the i-th sub-band, respectively. This is the cutoff angular frequency of the PR controller. The resonant angular frequency of the PR controller corresponding to the i-th sub-band. The parameters that constitute the PR controller corresponding to the i-th sub-band.

3. The adaptive broadband matching control method for electroacoustic transducers according to claim 2, characterized in that: The value satisfies the first and second conditions; The first condition is: All are positive numbers; in: ; proportionality coefficient k pwm It is the transfer function from the input of the PWM module to the output of the inverter bridge of the single-phase full-bridge inverter (30); The second condition is: steady-state error. Not greater than a preset error threshold; where: , This is the reference value for the output current. This is the measured value of the power amplifier output current. This is the inductance value of the first inductor.

4. The adaptive broadband matching control method for electroacoustic transducers according to claim 2, characterized in that: , , The value range is [15π, 25π] rad / s. The value range is [15, 30] rad / s.

5. The adaptive broadband matching control method for electroacoustic transducers according to claim 4, characterized in that: It is a constant value.

6. The adaptive broadband matching control method for an electroacoustic transducer according to claim 5, characterized in that: =20πrad / s。 7. The adaptive broadband matching control method for an electroacoustic transducer according to any one of claims 1-6, characterized in that: The proportional coefficient k of the proportional controller f The value range is [1, 5].

8. The adaptive broadband matching control method for an electroacoustic transducer according to any one of claims 1-6, characterized in that: The input impedance of the electroacoustic transducer (100) is inductive. The lumped parameter model of the electroacoustic transducer (100) includes a first static equivalent resistance (57) connected in series between the two driving terminals of the electroacoustic transducer (100), a nonlinear inductance model (52), a nonlinear resistance model (51), and a first vibration system equivalent circuit structure (V1). The inductance value of the nonlinear inductance model (52) is... The resistance value of the nonlinear resistance model (51) is... , .

9. The adaptive broadband matching control method for an electroacoustic transducer according to claim 8, characterized in that: The nonlinear inductance model (52) and the nonlinear resistance model (51) are connected in series to form an eddy current impedance model, and the inductance value of the nonlinear inductance model (52) is... Resistance value of nonlinear resistance model (51) The expression is: ； in, L is the first phase angle value. ex Here, p is the proportionality coefficient, q is the first coefficient, and q is the second coefficient. , .

10. The adaptive broadband matching control method for an electroacoustic transducer according to claim 8, characterized in that: The first vibration system equivalent circuit structure (V1) consists of the first vibration system equivalent resistor (53), the first vibration system equivalent inductor (54), and the first vibration system equivalent capacitor (55) connected in parallel.

11. The adaptive broadband matching control method for an electroacoustic transducer according to any one of claims 1-6, characterized in that: The inductance value L of the first inductor (2) s The capacitance value C of the first capacitor (1) s Satisfy the following formula: ； in, These are the inductance value of the first inductor and the capacitance value of the first capacitor, respectively; F n F is the resonant frequency of the LC filter composed of the first inductor (2) and the first capacitor (1); p Δi is the switching frequency of the switching transistors in the single-phase full-bridge inverter (30); ac_max It is 30% of the effective value of the rated output current of the power amplifier (20).

12. An adaptive broadband matching control device for an electroacoustic transducer, characterized in that, Includes a processor configured to perform the adaptive broadband matching control method for an electroacoustic transducer as described in any one of claims 1-11.

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