Ultrasonic automatic frequency tracking circuit

Abstract

The utility model discloses an ultrasonic automatic frequency tracking circuit, which relates to the technical field of automatic self-adaption and comprises an ultrasonic reference frequency generating unit, a metal oxide semiconductor (MOS) tube driving control unit, an MOS tube power amplification control unit and a high-frequency boosting control unit. The MOS tube control unit is connected with the MOS tube power amplification control unit, the MOS tube power amplification control unit is connected with the high-frequency boost control unit, and the high-frequency boost control unit outputs required ultrasonic signals to the load transducer; the high-frequency boost control unit is used for boosting an ultrasonic oscillation frequency signal, outputting a frequency signal matched with a load transducer, collecting and sorting the frequency signal of the load transducer and feeding back the frequency signal to the ultrasonic reference frequency generation unit, and the ultrasonic reference frequency generation unit adjusts the ultrasonic center oscillation frequency and outputs the ultrasonic center oscillation frequency. And automatic frequency tracking correction of the load transducer is realized. Usage is convenient, failure rate is low, and maintenance cost is low.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of self -adaptation, concretely relates to an ultrasonic automatic frequency tracking circuit. BACKGROUND

[0002] With the rapid development of modern science and technology, power ultrasonic system is widely used in ultrasonic cleaning, ultrasonic processing, ultrasonic welding and ultrasonic motor and the like. The power ultrasonic system is mainly composed of a high-frequency ultrasonic generator and an ultrasonic transducer, and the ultrasonic generator is an important component of the ultrasonic equipment and is responsible for providing ultrasonic frequency power to the ultrasonic transducer. In order to make the ultrasonic transducer work efficiently, not only the power provided by the ultrasonic generator is required to be sufficient, but also the frequency thereof is required to be consistent with the resonance frequency of the ultrasonic transducer. However, the resonance frequency of the ultrasonic transducer will change due to temperature, humidity and its own wear and tear, and if the frequency of the ultrasonic generator cannot change accordingly and remain consistent, the working efficiency will be reduced. If the frequency generated by the ultrasonic generator is inconsistent with the resonance frequency of the transducer for a long time, the transducer itself may be damaged.

[0003] The prior art power ultrasonic system is driven by a 220V alternating power source, such as the non-woven fabric ultrasonic cutting system with the announcement number CN216551269U, the control circuit of which is composed of multiple contactors and time relays, and cannot automatically adjust the resonance frequency matched with the transducer. Meanwhile, the contactors are relatively large in size, and it is inconvenient to reduce the size of the circuit board. Another patent application number CN202121209695.6 non-woven fabric ultrasonic cutting system has an input circuit including a rectifier circuit. The frequency tracking circuit in the prior art has the following disadvantages:

[0004] 1. It must be driven by a 220V power source, and the circuit is complex and high in cost, and cannot be carried conveniently. Meanwhile, the power conversion efficiency is low, and the loss is large.

[0005] 2. In the control mode, most of the existing ultrasonic control circuits adopt a manual frequency adjustment mode, and the frequency of the matched transducer and mold must be manually adjusted during use. However, as the use environment changes, such as the temperature rises and the humidity increases, the frequency of the load changes, and the output frequency cannot be automatically tracked, resulting in a mismatch with the load, thereby affecting the control accuracy of the ultrasonic output and causing the welding or cutting products to be defective.

[0006] 3. The existing ultrasonic control circuit adopts an analog self-excitation type oscillation circuit, and the power and amplitude cannot be automatically compensated due to the lack of pulse width adjustment. The protection circuit is not sensitive enough, and the amplitude power is small, the stability is poor, and the failure rate is high, and the maintenance rate is high. SUMMARY

[0007] The utility model aims at solving one of the prior art technical problems. For this purpose, the utility model embodiment proposes an ultrasonic automatic frequency tracking circuit, which is realized by a time base chip, a MOS tube, a MOS tube driving chip and other components.

[0008] The ultrasonic automatic frequency tracking circuit according to the embodiment of the utility model comprises: an ultrasonic reference frequency generating unit, a MOS tube driving control unit, a MOS tube power amplification control unit and a high-frequency voltage boosting control unit; the ultrasonic reference frequency generating unit is connected with the MOS tube driving control unit; the MOS tube control unit is connected with the MOS tube power amplification control unit; the MOS tube power amplification control unit is connected with the high-frequency voltage boosting control unit; and the high-frequency voltage boosting control unit outputs the required ultrasonic signal to a load transducer.

[0009] The ultrasonic reference frequency generating unit comprises a time base chip, which is used to generate a time base signal and an ultrasonic center oscillation frequency, and provide a frequency signal source for the driving control unit circuit and output a PWM signal with fixed timing and frequency.

[0010] The MOS tube driving control unit comprises a MOS tube driving chip, which is used to amplify, start and stop and process the waveform of the ultrasonic oscillation frequency signal source input by the ultrasonic reference frequency generating unit, form a driving signal and then input the driving signal to the MOS tube power amplification control unit.

[0011] The MOS tube power amplification control unit is used to output the ultrasonic oscillation frequency signal source after power amplification to the high-frequency voltage boosting control unit.

[0012] The high-frequency voltage boosting control unit is used to boost the ultrasonic oscillation frequency signal, output a frequency signal matched with the load transducer, collect and arrange the frequency signal of the load transducer, feed back to the ultrasonic reference frequency generating unit, adjust the ultrasonic center oscillation frequency by the ultrasonic reference frequency generating unit and realize automatic frequency tracking correction of the load transducer.

[0013] Further, the ultrasonic reference frequency generating unit further comprises a voltage stabilizing circuit, a time base center frequency adjusting circuit and a feedback signal processing circuit; the voltage stabilizing circuit is connected with the power input end of the time base chip and provides voltage to the time base chip; the time base center frequency adjusting circuit is connected with the control end of the time base chip and is used to adjust the center frequency of the time base chip; the feedback signal processing circuit is connected with the trigger end of the time base chip; and the output end of the time base chip is connected with the high-frequency voltage boosting control unit.

[0014] Further, the MOS tube driving control unit further comprises: a direct current voltage stabilizing circuit, an ultrasonic switch control circuit, and a MOS tube driving waveform correction circuit, the direct current voltage stabilizing circuit is connected with a MOS tube driving chip power supply end, the ultrasonic switch control circuit is connected with the MOS tube driving chip SD end, and is used for controlling an ultrasonic signal switch, and the MOS tube driving chip HO end and IO end are connected with the MOS tube driving waveform correction circuit.

[0015] Further, the MOS tube power amplification control unit comprises: a double tube push-pull circuit and an amplification bypass filter circuit, the double tube push-pull circuit is composed of a first field effect tube and a second field effect tube, the first field effect tube G pole is connected in parallel with a third diode positive pole and a twelfth resistor one end, a third diode negative pole is connected in parallel with the MOS tube driving chip LO end and a twelfth resistor other end, the second field effect tube G pole is connected in parallel with a sixth diode positive pole and a third resistor one end, and a sixth diode negative pole is connected in parallel with the MOS tube driving chip HO end and a third resistor other end.

[0016] Further, the high frequency voltage boosting control unit comprises: a high voltage boosting transformer, an LC matching resonant circuit, and a high voltage output voltage, current and phase sampling circuit, the high voltage boosting transformer input end is connected with the MOS tube power amplification control unit, the high voltage boosting transformer output end is connected with the LC matching resonant circuit, and the high voltage output voltage, current and phase sampling circuit is connected with the ultrasonic reference frequency generating unit.

[0017] Further, the time base chip model is NE555.

[0018] Further, the MOS tube driving chip model is IR2104.

[0019] Further, the first pin of the time base chip is grounded, the second pin of the time base chip is connected with one end of the 48th capacitor and one end of the 41st resistor, the sixth pin of the time base chip is connected in parallel, the other end of the 48th capacitor is grounded, the fifth pin of the time base chip is connected with one end of the 50th capacitor, the other end of the 50th capacitor is grounded; the eighth and fourth pins of the time base chip are connected with VDD5, the third pin of the time base chip is connected with one end of the 55th resistor, the other end of the 55th resistor is connected with the IN end of the second pin of the MOS tube driving chip, the seventh pin of the time base chip is connected with the collector of the triode, the emitter of the triode is connected with the ground, the seventh pin of the time base chip is connected with the first end of the adjustable resistor RV2, the second end of the adjustable resistor is connected with one end of the 51st resistor, the other end of the 51st resistor is connected with the sixth pin of the time base chip, the eighth pin of the time base chip is connected with one end of the 21st capacitor, the other end of the 21st capacitor is grounded; the other end of the 41st resistor is connected with one end of the 39th capacitor, the other end of the 39th capacitor is connected with one end of the 49th capacitor, the 20th resistor and the fourth end of the first step-up transformer, the other end of the 49th capacitor is connected with the other end of the 20th resistor, the fifth end of the first step-up transformer and grounded in parallel, the third pin of the first step-up transformer is connected with the first end of LR2, the second end of LR2 is connected with one end of the 9th capacitor, one end of the 11th capacitor and OUT+ in parallel; the end of the first step-up transformer is connected with OUT-, the second end of the first step-up transformer is connected with the other end of the 9th capacitor and the fourth end of the second step-up transformer in parallel, the other end of the 11th capacitor is connected with the fifth pin of the second step-up transformer, the first pin of the second step-up transformer is connected with the D pole of the first MOS tube, the second pin of the second step-up transformer is connected with the VCC end and one end of the 41st capacitor, the + pole of the CE capacitor, the other end of the 41st capacitor is connected with the other end of the CE3 capacitor and grounded in parallel; the third pin of the second step-up transformer is connected with the D pole of the second MOS tube, the S pole pin of the first MOS tube is grounded; the S pole of the second MOS tube is grounded; the fourth pin of the MOS tube driving chip is grounded, the third pin of the MOS tube driving chip is connected with the second end of the 6th resistor, the first end of the 6th resistor is connected with one end of S1, the other end of S1 is connected with VDD5, the first pin of the MOS tube driving chip is connected with VDD and one end of the 10th capacitor in parallel, the other end of the 10th capacitor is grounded, the eighth pin of the MOS tube driving chip is connected with VDD, the sixth pin of the MOS tube driving chip is grounded, the seventh pin of the MOS tube driving chip is connected with the HO end of the 3rd resistor, the negative pole of the 6th diode in parallel, the other end of the 3rd resistor is connected with the positive pole of the 6th diode and the gate of the second MOS tube, the fifth pin of the MOS tube driving chip is connected with one end of the 12th resistor, the negative pole of the 3rd diode in parallel, the other end of the 12th resistor is connected with the positive pole of the 3rd diode and the gate of the first MOS tube.

[0020] The ultrasonic automatic frequency tracking circuit has the advantages that: the automatic frequency tracking ultrasonic control circuit driven by low voltage and outputting high power is adopted, the automatic frequency tracking ultrasonic wave adopts self-adaptive load frequency matching technology, and the ultrasonic frequency can be automatically adjusted to adapt to different transducers and mold matching.

[0021] The automatic frequency tracking ultrasonic control circuit feeds back to the control signal generating function chip after signal sampling processing, and outputs high voltage matching through the high-voltage step-up transformer after amplification by the power amplification module.

[0022] The circuit has the advantages of improving the reliability and stability of ultrasonic wave starting, simplifying the circuit by adopting the integrated chip, and reducing the volume of the circuit board.

[0023] The additional aspects and advantages of the present application will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0024] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the following drawings in which:

[0025] Figure 1 A composition schematic diagram of the automatic frequency tracking ultrasonic control circuit is provided for the embodiments of the present application;

[0026] Figure 2 A principle block diagram of the automatic frequency tracking ultrasonic control circuit is provided for the embodiments of the present application;

[0027] Figure 3 A principle schematic diagram of the automatic frequency tracking ultrasonic control circuit is provided for the embodiments of the present application.

[0028] REFERENCE NUMERALS

[0029] Time base chip NE555, MOS tube driving chip U6, MOS tube Q1, MOS tube Q2, step-up transformer T1, step-up transformer T2;

[0030] Direct current power supply / battery ①, DC / AC ②, filter ③, sampling feedback, automatic frequency tracking ④, timing frequency PWM generation ⑤, interlock driving ⑥, electric energy / ultrasonic wave output ⑦. DETAILED DESCRIPTION

[0031] The embodiments of the present application are described below in detail, examples of which are shown in the drawings, wherein the same or similar notations represent the same or similar elements having the same or similar functions throughout. The embodiments described below by reference to the drawings are exemplary only, and are used merely for the purpose of explaining the present application, and should not be construed as limiting the present application.

[0032] In the description of the present application, unless otherwise explicitly defined, the words such as setting, installing, connecting, etc. should be understood in a broad sense, and the skilled in the art can determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0033] With the rapid development of modern science and technology, power ultrasonic system is widely used in ultrasonic cleaning, ultrasonic processing, ultrasonic welding and ultrasonic motor. The power ultrasonic system mainly consists of a high-frequency ultrasonic generator and an ultrasonic transducer. The ultrasonic generator is an important part of the ultrasonic equipment, which is responsible for providing ultrasonic frequency power to the ultrasonic transducer. In order to make the ultrasonic transducer work efficiently, not only the power provided by the ultrasonic generator is required to be sufficient, but also the frequency is required to be consistent with the resonant frequency of the ultrasonic transducer. The resonant frequency of the ultrasonic transducer will change due to temperature, humidity and its own wear, etc. If the frequency of the ultrasonic generator cannot change accordingly and remain consistent, it will lead to a decrease in work efficiency. If the frequency generated by the ultrasonic generator is inconsistent with the resonant frequency of the transducer for a long time, it may cause damage to the transducer itself. Therefore, it is particularly necessary to find an automatic control system that can complete the automatic tracking of the ultrasonic power to the transducer frequency, which can quickly and accurately find a new resonant frequency to realize frequency automatic tracking.

[0034] Based on this, the embodiment of the present application proposes an ultrasonic automatic frequency tracking circuit, which adopts a low-voltage driven high-power output automatic frequency tracking ultrasonic control circuit. The ultrasonic automatic frequency tracking is a kind of adaptive load frequency matching technology, which can automatically adjust the frequency to adapt to different transducers and mold matching. This technology can be driven by low voltage (12V-72V) and has high power output. The circuit has signal sampling processing, feedback control signal generation function chip, power amplification module and high voltage conversion matching output. The circuit improves the reliability and stability of ultrasonic starting, simplifies the circuit by using integrated chip, and reduces the volume of the circuit board.

[0035] Please refer to Figure 1 and Figure 2 , the ultrasonic automatic frequency tracking circuit according to the embodiment of the present application, and the principle block diagram is described as follows:

[0036] In the embodiment, the direct current power supply or battery provides power input for the circuit, which is filtered through the DC / AC module and then outputs power or ultrasonic waves. The timing and frequency PWM signal is generated by the time base chip after sampling feedback from the filtering module and automatic frequency tracking processing. The timing and frequency PWM signal is output to the DC / AC through the interlock driving module.

[0037] Preferably, referring to Figure 2 and Figure 3 , the technical scheme of the utility model structure comprises 4 parts:

[0038] 1. The ultrasonic reference frequency generating part comprises: a NE555 time base chip, a 5V stabilizing circuit, a time base central frequency adjusting circuit, and a feedback signal processing circuit.

[0039] 2. The MOS tube driving control part comprises: a DC13V direct current stabilizing circuit, an ultrasonic switch control circuit, and a MOS tube driving waveform correction circuit.

[0040] 3. The MOS tube power amplification control part comprises: a double tube push-pull circuit and an amplification bypass filter circuit.

[0041] 4. The high frequency voltage boosting control part comprises: a high voltage boosting transformer, an LC matching resonant circuit, a high voltage output voltage, a current, and a phase sampling circuit. In the embodiment, the high voltage boosting transformer comprises two.

[0042] Please refer to Figure 2 and Figure 3 , the embodiment further describes the ultrasonic automatic frequency tracking circuit:

[0043] The first part of the ultrasonic reference frequency generating circuit comprises: a NE555 time base chip, an attached 5V stabilizing circuit, an attached time base central frequency adjusting circuit, and a feedback signal processing circuit, which generates the ultrasonic central oscillation frequency. The main function is to provide a signal source for the MOS tube driving circuit.

[0044] The second part of the MOS tube driving control part comprises: a DC13V direct current stabilizing circuit, an ultrasonic switch control circuit, and a MOS tube driving waveform correction circuit. The main function is to amplify, start and stop, process the waveform of the frequency signal source input from the previous stage, and input the driving signal to the MOS tube.

[0045] The third part of the MOS tube power amplification control circuit comprises: a double tube push-pull circuit and an amplification bypass filter circuit. The main function is to amplify the power of the ultrasonic signal source.

[0046] The fourth part high-frequency boost control circuit part is composed of high-voltage boost transformer, LC matching resonant circuit, high-voltage output voltage, current, phase sampling circuit and the like, and mainly functions to boost high-frequency ultrasonic signals, match the frequency of the load transducer and the mold, sample and arrange signals and feed back to the source time base signal, and realize automatic frequency tracking correction.

[0047] The utility model improves the input control of the prior ultrasonic control circuit technology, and its main technical highlights are as follows:

[0048] 1. Low-voltage power supply can be used for common electric tool battery pack power supply, safer, small and portable;

[0049] 2. Small size, high power improves conversion efficiency and reduces energy consumption;

[0050] 3. Increase the feedback circuit for voltage, current, phase sampling circuit;

[0051] 4. Adopting chip control circuit, control is more accurate.

[0052] The automatic frequency tracking circuit tracks the working frequency of the machine equipment, avoids the trouble of adjusting the working frequency of the machine every time the ultrasonic transducer and the mold load are replaced, is convenient to use, has low failure rate, greatly reduces the maintenance cost, and has longer service life.

[0053] Please refer to Figure 3 , it is a kind of schematic diagram of the principle of an automatic frequency tracking circuit. Its connection mode is briefly described as follows:

[0054] The first pin of the time base chip is connected with ground, the second pin of the time base chip is connected with one end of the capacitor 48 and one end of the resistor 41, the sixth pin of the time base chip is connected in parallel, the other end of the capacitor 48 is connected with ground, the fifth pin of the time base chip is connected with one end of the capacitor 50, the other end of the capacitor 50 is connected with ground; the eighth pin and the fourth pin of the time base chip are connected with VDD5, the third pin of the time base chip is connected with one end of the resistor 55, the other end of the resistor 55 is connected with the IN end of the second pin of the MOS tube driving chip, the seventh pin of the time base chip is connected with the collector of the triode, the emitter of the triode is connected with ground, the seventh pin of the time base chip is connected with the first end of the adjustable resistor RV2, the second end of the adjustable resistor is connected with one end of the resistor 51, the other end of the resistor 51 is connected with the sixth pin of the time base chip, the eighth pin of the time base chip is connected with one end of the capacitor 21, the other end of the capacitor 21 is connected with ground; the other end of the resistor 41 is connected with one end of the capacitor 39, the other end of the capacitor 39 is connected with one end of the capacitor 49, the resistor 20 and the fourth end of the first step-up transformer, the other end of the capacitor 49 is connected with the other end of the resistor 20, the fifth end of the first step-up transformer and ground in parallel, the third pin of the first step-up transformer is connected with the first end of LR2, the second end of LR2 is connected with one end of the capacitor 9, one end of the capacitor 11 and OUT+ in parallel; the first end of the first step-up transformer is connected with OUT-, the second end of the first step-up transformer is connected with the other end of the capacitor 9 and the fourth end of the second step-up transformer in parallel, the other end of the capacitor 11 is connected with the fifth pin of the second step-up transformer, the first pin of the second step-up transformer is connected with the D pole of the first MOS tube, the second pin of the second step-up transformer is connected with VCC, one end of the capacitor 41 and the positive pole of the capacitor CE in parallel, the other end of the capacitor 41 is connected with the other end of the capacitor CE3 and ground in parallel; the third pin of the second step-up transformer is connected with the D pole of the second MOS tube, the S pole pin of the first MOS tube is connected with ground; the S pole of the second MOS tube is connected with ground; the fourth pin of the MOS tube driving chip is connected with ground, the third pin of the MOS tube driving chip is connected with the second end of the resistor 6, the first end of the resistor 6 is connected with one end of S1, the other end of S1 is connected with VDD5, the first pin of the MOS tube driving chip is connected with VDD and one end of the capacitor 10 in parallel, the other end of the capacitor 10 is connected with ground, the eighth pin of the MOS tube driving chip is connected with VDD, the sixth pin of the MOS tube driving chip is connected with ground, the seventh pin of the MOS tube driving chip is connected with the HO end of the resistor 3, the negative pole of the diode 6 and the gate of the second MOS tube in parallel, the other end of the resistor 3 is connected with the positive pole of the diode 6 and the gate of the first MOS tube, the fifth pin of the MOS tube driving chip is connected with one end of the resistor 12, the negative pole of the diode 3 and the gate of the first MOS tube in parallel. In the embodiment, the type of the time base chip is NE555, and the type of the MOS tube driving chip is IR2104.

[0055] In the embodiment, the NE555 chip is a widely used and quite common time base chip, and only a few resistors and capacitors are needed to generate various different frequency pulse signals required by digital circuits, the output end can provide a large current to directly drive various automatic control loads, and can cooperate with TTL, CMOS and other logic circuits, that is, the output level and input trigger level can match the high and low levels of these series of logic circuits. The IR2104 chip is a MOS tube driving chip, and the boot circuit in the IR2104 chip driving circuit is used to provide a high voltage source to drive the high side switch tube (that is, Vgs>Vth), so as to ensure that the MOS tube can be fully turned on. The boot circuit charges by using the conduction of the low side switch tube, and the charging voltage is raised to a level higher than the power supply voltage, and then provided to the high side driver through the driving circuit. In this way, the high side switch tube can be fully turned on, so that effective H-bridge driving is realized.

[0056] In the embodiment, the circuit principle is as follows:

[0057] The reference oscillation frequency output by the time base chip NE555 chip 3 is output to the 2 pin of the MOS tube driving chip IR2104, the 3 pin of the chip IR2104 controls the opening and closing of the ultrasonic oscillation signal, and the 5 pin and the 7 pin of the MOS tube driving chip IR2104 respectively drive the push-pull amplification circuit composed of two MOS tubes to be boosted through a high-frequency transformer, and the LC load transducer and mold frequency matching composed of an output inductor and a capacitor, and the signal sampling and arrangement is fed back to the 6 pin of the source chip NE555 to control the frequency of the time base signal, so that the frequency automatic tracking correction is realized.

[0058] The driving circuit of the embodiment relates to the frequency generation circuit of the chip NE555, the driving control circuit of the chip IR2104, the MOS tube power amplification circuit, the high-voltage output circuit, the LC resonance matching circuit and the output circuit.

[0059] In the embodiment, the automatic frequency tracking circuit is used to track the working frequency of the machine equipment, so that the trouble of adjusting the working frequency of the machine every time the ultrasonic transducer and the mold load are replaced is avoided, the use is convenient, the failure rate is low, the maintenance cost is greatly reduced, and the service life is longer.

[0060] The embodiments of the utility model are described in detail in combination with the drawings above, but the utility model is not limited to the above-mentioned embodiments, and various changes can be made within the knowledge range possessed by ordinary skilled persons in the technical field without departing from the purpose of the utility model.

[0061] The apparatus embodiments described above are merely illustrative, wherein the units described as separate components can or can not be physically separate, i.e., can be located in one place, or can also be distributed to multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purposes of the embodiments.

[0062] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "an illustrative embodiment", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0063] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. An ultrasonic automatic frequency tracking circuit, characterized in that, The ultrasonic automatic frequency tracking circuit includes: an ultrasonic reference frequency generating unit, a MOS transistor drive control unit, a MOS transistor power amplification control unit, and a high-frequency boost control unit. The ultrasonic reference frequency generating unit is connected to the MOS transistor drive control unit, the MOS transistor control unit is connected to the MOS transistor power amplification control unit, the MOS transistor power amplification control unit is connected to the high-frequency boost control unit, and the high-frequency boost control unit outputs the required ultrasonic signal to the load transducer. The ultrasonic reference frequency generating unit includes a time base chip, which is used to generate a time base signal and the ultrasonic center oscillation frequency, providing a frequency signal source for the drive control unit circuit, and outputting a PWM signal at a fixed time and frequency. The MOS transistor drive control unit includes a MOS transistor drive chip, which is used to amplify, start and stop, and process the ultrasonic oscillation frequency signal source input from the ultrasonic reference frequency generating unit to form a drive signal, which is then input to the MOS transistor power amplification control unit. The MOS transistor power amplifier control unit is used to amplify the ultrasonic oscillation frequency signal source and output it to the high-frequency boost control unit. The high-frequency boost control unit is used to boost the ultrasonic oscillation frequency signal, output a frequency signal that matches the load transducer, collect and organize the load transducer frequency signal, and feed it back to the ultrasonic reference frequency generating unit. The ultrasonic reference frequency generating unit adjusts the ultrasonic center oscillation frequency to achieve automatic frequency tracking and correction of the load transducer.

2. The ultrasonic automatic frequency tracking circuit according to claim 1, characterized in that, The ultrasonic reference frequency generating unit further includes: a voltage regulator circuit, a time base center frequency adjustment circuit, and a feedback signal processing circuit. The voltage regulator circuit is connected to the power input terminal of the time base chip and provides voltage to the time base chip. The time base center frequency adjustment circuit is connected to the control terminal of the time base chip and is used to adjust the center frequency of the time base chip. The feedback signal processing circuit is connected to the trigger terminal of the time base chip. The output terminal of the time base chip is connected to the high-frequency boost control unit.

3. The ultrasonic automatic frequency tracking circuit according to claim 1, characterized in that, The MOS transistor drive control unit further includes: a DC voltage regulator circuit, an ultrasonic switch control circuit, and a MOS transistor drive waveform correction circuit. The DC voltage regulator circuit is connected to the power supply terminal of the MOS transistor drive chip. The ultrasonic switch control circuit is connected to the SD terminal of the MOS transistor drive chip and is used to control the ultrasonic signal switch. The HO terminal and IO terminal of the MOS transistor drive chip are connected to the MOS transistor drive waveform correction circuit.

4. The ultrasonic automatic frequency tracking circuit according to claim 1, characterized in that, The MOSFET power amplifier control unit includes: a dual-tube push-pull circuit and an amplification bypass filter circuit. The dual-tube push-pull circuit consists of a first field-effect transistor and a second field-effect transistor. The gate of the first field-effect transistor is connected in parallel with the anode of the third diode and one end of the twelfth resistor. The cathode of the third diode is connected in parallel with the LO terminal of the MOSFET driver chip and the other end of the twelfth resistor. The gate of the second field-effect transistor is connected in parallel with the anode of the sixth diode and one end of the third resistor. The cathode of the sixth diode is connected in parallel with the HO terminal of the MOSFET driver chip and the other end of the third resistor.

5. The ultrasonic automatic frequency tracking circuit according to claim 1, characterized in that, The high-frequency boost control unit includes: a high-voltage boost transformer, an LC matching resonant circuit, and a high-voltage output voltage, current, and phase sampling circuit. The input terminal of the high-voltage boost transformer is connected to the MOS transistor power amplifier control unit, the output terminal of the high-voltage boost transformer is connected to the LC matching resonant circuit, and the high-voltage output voltage, current, and phase sampling circuit is connected to the ultrasonic reference frequency generating unit.

6. The ultrasonic automatic frequency tracking circuit according to claim 1, characterized in that, The time base chip is model NE555.

7. The ultrasonic automatic frequency tracking circuit according to claim 1, characterized in that, The MOS transistor driver chip is model IR2104.

8. The ultrasonic automatic frequency tracking circuit according to claim 1, characterized in that, The timer chip has the following connections: pin 1 is grounded; pin 2 is connected in parallel with one end of capacitor 48, one end of resistor 41, and pin 6; the other end of capacitor 48 is grounded; pin 5 is connected to one end of capacitor 50, and the other end of capacitor 50 is grounded; pins 8 and 4 are connected to VDD5; pin 3 is connected to one end of resistor 55, and the other end of resistor 55 is connected to pin 2 (IN) of the MOS transistor driver chip; pin 7 is connected to the collector of the transistor, and the emitter of the transistor is connected to ground; pin 7 is also connected to the first end of adjustable resistor RV2. Terminal 2 is connected to one end of resistor 51, and the other end of resistor 51 is connected to pin 6 of the time base chip. Pin 8 of the time base chip is connected to one end of capacitor 21, and the other end of capacitor 21 is grounded. The other end of resistor 41 is connected to one end of capacitor 39. The other end of capacitor 39 is connected to one end of capacitor 49, resistor 20, and terminal 4 of the first boost transformer. The other end of capacitor 49 is connected to the other end of resistor 20 and terminal 5 of the first boost transformer in parallel to ground. Pin 3 of the first boost transformer is connected to terminal 1 of LR2. Terminal 2 of LR2 is connected in parallel to one end of capacitor 9, one end of capacitor 11, and terminal OUT+. Terminal 1 of the first boost transformer is connected to terminal OUT-. The second terminal of the first step-up transformer is connected in parallel with the other end of the ninth capacitor, and the fourth terminal of the second step-up transformer is connected in parallel. The other end of the eleventh capacitor is connected to the fifth pin of the second step-up transformer. The first pin of the second step-up transformer is connected to the drain of the first MOSFET. The second pin of the second step-up transformer is connected to the VCC terminal, one end of the fourth capacitor, and the positive terminal of the CE capacitor. The other end of the fourth capacitor is connected in parallel with the other end of the CE3 capacitor and grounded. The third pin of the second step-up transformer is connected to the drain of the second MOSFET, and the source pin of the first MOSFET is grounded. The source pin of the second MOSFET is grounded. The fourth pin of the MOSFET driver chip is grounded. The third pin of the MOSFET driver chip is connected to the second terminal of the sixth resistor. The first terminal is connected to one end of S1, and the other end of S1 is connected to VDD5. The first pin of the MOS transistor driver chip is connected in parallel with the VDD terminal and one end of the 10th capacitor. The other end of the 10th capacitor is grounded. The 8th pin of the MOS transistor driver chip is connected to the VDD terminal. The 6th pin of the MOS transistor driver chip is grounded. The HO terminal of the 7th pin of the MOS transistor driver chip is connected in parallel with one end of the 3rd resistor and the negative terminal of the 6th diode. The other end of the 3rd resistor is connected in parallel with the positive terminal of the 6th diode and the gate of the 2nd MOS transistor. The 5th pin of the MOS transistor driver chip is connected in parallel with one end of the 12th resistor and the negative terminal of the 3rd diode. The other end of the 12th resistor is connected in parallel with the positive terminal of the 3rd diode and the gate of the 1st MOS transistor.

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