Magnetostrictive detection method and detection system based on adaptive signal conditioning

Abstract

The application discloses a magnetostrictive detection method and system based on adaptive signal conditioning, and belongs to the technical field of measuring instruments, comprising an efficient single-tube switching boost circuit and an innovative adaptive signal conditioning circuit. Through microcontroller driving, two digital potentiometers are adjusted by using an SPI bus linkage to control the gain of an operational amplifier and the threshold voltage of a comparator, thereby realizing synchronous adaptive matching of echo signal amplitude and decision threshold. The system has a data learning function, can store optimal configuration parameters and bind them with specific probes, and realizes quick automatic adaptation after replacement or historical parameter calling. The application realizes manual calibration-free replacement of components, significantly improves measurement accuracy, reliability and use efficiency, and reduces maintenance cost.

Description

Technical Field

[0001] This invention relates to the field of measuring instrument technology, and in particular to a magnetostriction detection method and system based on adaptive signal conditioning. Background Technology

[0002] Liquid level measurement typically involves both contact and non-contact methods. Contact methods include glass tube level gauges, float level gauges, and servo level gauges. Hydrostatic level gauges can also be used, based on the principle that liquid static pressure is proportional to liquid level. By measuring the static pressure at a point at the bottom of the container (or the pressure difference with the top), and given the liquid density ρ, the liquid level height h is calculated. Capacitive level gauges use a metal rod as one electrode and the container wall as the other, forming a capacitor. Changes in liquid level cause changes in the dielectric constant between the electrodes, resulting in a change in capacitance, which is then used to measure the liquid level. Resistance (electrical contact) level gauges utilize the conductivity of the liquid itself; changes in liquid level cause changes in the resistance between the electrodes, and the liquid level is determined by measuring the resistance. Alternatively, electrodes can be installed at a specific height, and a switching signal is output based on whether the liquid level indicates the continuity of a circuit. Energy fields can also be used for non-contact measurement, including ultrasonic level gauges, radar level gauges, and laser level gauges. However, when measuring industrial petroleum and other chemical products, extremely high accuracy is required. Ordinary contact level measurement devices are prone to jamming, while non-contact measurements are easily affected by vapors or volatile gases and foams generated by containers and liquids / colloids, resulting in too low measurement accuracy, which cannot meet the accuracy requirements when conducting product transactions.

[0003] Therefore, a magnetostrictive level gauge is typically selected for measuring the liquid level of such products. Generally, a magnetostrictive level gauge consists of three parts (such as...). Figure 1 (As shown): The system consists of a probe rod 2, a circuit unit 1, and a float 3. During measurement, the circuit unit generates a current pulse, which propagates downwards along the magnetostrictive lines and produces a circular magnetic field. A float is placed outside the probe rod, moving up and down along the probe rod as the liquid level changes. Since the float contains a set of permanent magnets, it also generates a magnetic field. When the current magnetic field meets the float's magnetic field, a "torsion" pulse, or "return" pulse, is generated. The time difference between the "return" pulse and the current pulse is converted into a pulse signal, thereby calculating the actual position of the float and measuring the liquid level. However, ordinary magnetostrictive level gauges cannot adaptively match different measurement ranges. In existing magnetostrictive detection devices, the probe rod is fixed, and different probe rod lengths correspond to different test circuits to achieve different liquid level tests; that is, a shorter probe rod results in a smaller measurement range, and a larger probe rod results in a larger measurement range.

[0004] When testing the liquid level of different tanks, it is necessary to select a magnetostrictive level gauge with an appropriate range according to the size of the tank. It can be seen that the existing magnetostrictive level gauges cannot be universally adapted to different testing requirements. Therefore, this application studies a magnetostrictive detection method and detection system based on adaptive signal conditioning. Summary of the Invention

[0005] Therefore, the purpose of this invention is to provide a magnetostriction detection method and system based on adaptive signal conditioning, which adopts a magnetostriction boost circuit with simple structure and high conversion efficiency to increase the dynamic gain range and realize the adjustment of different ranges.

[0006] To achieve the above objectives, the present invention provides a magnetostriction detection system based on adaptive signal conditioning, including a power supply circuit, a boost module, an adaptive signal conditioning circuit, and a microcontroller.

[0007] The power supply circuit is used to generate an excitation voltage to generate a reference magnetic field for magnetostriction.

[0008] The boost module is connected to the power supply circuit and the microcontroller. It boosts the excitation voltage generated by the power supply circuit according to the control signal of the microcontroller to form a first magnetic field that is higher than the reference magnetic field.

[0009] The microcontroller is used to receive the echo signal generated by the magnetostrictive sensor in the reference magnetic field, and to judge the echo signal. When the echo signal is less than the lower limit of the first preset range, it is judged to switch to the large range state; when the echo signal is greater than the upper limit of the first preset range, it is judged to switch to the small range state.

[0010] When switching to the large range state, the microcontroller boosts the excitation voltage and / or adjusts the echo signal gain by increasing the resistance of the first and second digital potentiometers, amplifying the echo signal and adjusting the large range so that the echo signal is within the large range range, and outputs the detection value.

[0011] When switching to the small range mode, the microcontroller only adjusts the echo signal gain. By reducing the resistance of the first and second digital potentiometers, the echo signal is reduced and the range is decreased, so that the echo signal is within the small range range and the detection value is output.

[0012] The adaptive signal conditioning circuit receives the echo signal gain adjustment signal from the microcontroller and changes the resistance values ​​of the first digital potentiometer and the second digital potentiometer.

[0013] More preferably, the power supply circuit is connected to the boost module; it adopts a single-transistor switching topology; and includes: a switching transistor, an energy storage inductor, a diode, a first energy storage capacitor C60, and a second energy storage capacitor C61; one end of the energy storage inductor L5 is connected to the input power supply MP50, and the other end is connected to the collector of the switching transistor Q7 and the anode of the diode D26; the base of the switching transistor Q7 receives the pulse signal PULSE generated by the microcontroller, and the emitter is grounded; the cathode of the diode D26 is connected to one end of the first energy storage capacitor C60, one end of the second energy storage capacitor C61, and the high-voltage output terminal HPower, and the other ends of the first energy storage capacitor C60 and the second energy storage capacitor C61 are grounded.

[0014] Further preferably, the adaptive signal conditioning circuit includes a first-stage filter circuit, a two-stage programmable gain amplifier circuit, and a first-stage programmable threshold comparison circuit; the first-stage filter circuit is used to filter the received echo signal; the input terminals of the two-stage programmable gain amplifier circuit are connected to the output terminals of the first-stage filter circuit, and the gain of the two-stage programmable gain amplifier circuit is determined by the microcontroller adjusting the resistance value of the first digital potentiometer U16; the programmable threshold comparison circuit includes a comparator and a second digital potentiometer U19, the first input terminal of which is connected to the output terminals of the two-stage programmable gain amplifier circuit, and the input terminal of which is connected to the output terminal of the second digital potentiometer U19, generating a programmable reference voltage Vref.

[0015] More preferably, the two-stage programmable gain amplifier circuit includes a first operational amplifier U15, a second operational amplifier U17, and a feedback resistor network; the feedback resistor network is composed of the fixed terminal and the sliding terminal of the first digital potentiometer U16 connected in parallel, and then connected in series with a fixed resistor; the fixed terminal of the first digital potentiometer is connected to the inverting output terminal of the second operational amplifier, and the other end of the series resistor network is connected to the negative input terminal of the second operational amplifier U17.

[0016] More preferably, the microcontroller adjusts the first digital potentiometer U16 via the SPI bus to change the gain of the two-stage programmable gain amplifier circuit, thereby adapting to echo signals of different intensities.

[0017] More preferably, the microcontroller adjusts the resistance of the second digital potentiometer U19 via the same SPI bus to change the programmable reference voltage Vref, thereby adapting to the range of different echo signals.

[0018] More preferably, the microcontroller is configured to: after adjusting the first digital potentiometer U16 to change the gain, synchronously and in conjunction with adjusting the second digital potentiometer U19, so that the programmable reference voltage Vref is adapted to the amplified signal level.

[0019] Further preferably, the system also includes a storage module; the storage module is configured with the optimal configuration parameters obtained after adaptive adjustment; the microcontroller is also configured to: before performing adaptive adjustment, first query whether there are matching historical configuration parameters in the non-volatile memory, and if so, directly call the historical configuration parameters to configure the system.

[0020] More preferably, the storage module stores multiple sets of optimal configuration parameters, each set of optimal configuration parameters being associated with a specific probe component identifier and the current working timestamp; the microcontroller is configured to select and load a corresponding set of configuration parameters from the multiple sets of configuration parameters based on the probe component identifier input by the user or automatically identified.

[0021] This invention also provides a magnetostriction detection method based on adaptive signal conditioning, implemented based on the above-mentioned magnetostriction detection system based on adaptive signal conditioning, including the following steps:

[0022] S1. Automatic reset is performed after power-on. During the automatic reset, the microcontroller sets the digital potentiometer to the middle value and controls the PWM pin to reset to the reference voltage.

[0023] S2. Based on the reference voltage, the boost module of the power supply circuit is in the off state, and the power supply circuit emits a reference pulse to form a reference magnetic field.

[0024] S3. Acquire the echo signal generated by the magnetostrictive sensor in the reference magnetic field, and judge the echo signal. When the echo signal is less than the lower limit of the first preset range, it is judged to switch to the large range state; when the echo signal is greater than the upper limit of the first preset range, it is judged to switch to the small range state.

[0025] S4. When switching to the large range state, the microcontroller boosts the excitation voltage and / or adjusts the echo signal gain by increasing the resistance values ​​of the first and second digital potentiometers to adjust the large range, so that the echo signal is within the large range range and outputs the detection value.

[0026] When switching to the small range mode, the microcontroller only adjusts the echo signal gain. By reducing the resistance of the first and second digital potentiometers, the range is reduced, so that the echo signal is within the small range and the detection value is output.

[0027] The magnetostriction detection method and system based on adaptive signal conditioning disclosed in this application have at least the following advantages compared with the prior art.

[0028] This invention utilizes a microcontroller to execute an adaptive algorithm, automatically acquiring echo signals and intelligently adjusting gain and comparison thresholds after probe replacement, enabling the system to quickly reach its optimal operating state. Its unique data learning function binds and stores optimal parameters with a specific probe, allowing for direct recall of historical configurations upon subsequent replacements, achieving "plug and play." This completely eliminates the cumbersome manual calibration process required by traditional equipment, significantly reducing the user's operational threshold and maintenance time.

[0029] This invention employs a single-transistor boost circuit, which is simple in structure, highly efficient, and inexpensive. Its core innovation lies in using the boost circuit and dual digital potentiometers for synchronized adjustment via an SPI bus. This ensures that the signal gain amplification and the comparison decision threshold remain synchronously matched, effectively solving the problem of false triggering that may result from single adjustment. Thus, it guarantees extremely high measurement accuracy and stability even under complex operating conditions. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the magnetostriction detector mentioned in the background section;

[0031] Figure 2 A schematic diagram of the circuit structure of the magnetostriction detection system based on adaptive signal conditioning provided by the present invention;

[0032] Figure 3 This is a schematic diagram of the circuit structure of a boost circuit provided in one embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of the circuit structure of the adaptive signal conditioning circuit in another embodiment of the present invention;

[0034] Figure 5 This is a flowchart of the magnetostriction detection method based on adaptive signal conditioning according to the present invention. Detailed Implementation

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] like Figure 2 As shown, one embodiment of the present invention provides a magnetostriction detection system based on adaptive signal conditioning, including a power supply circuit, a boost module, an adaptive signal conditioning circuit, and a microcontroller;

[0037] The power supply circuit is used to generate an excitation voltage to generate a reference magnetic field for magnetostriction.

[0038] The boost module is connected to the power supply circuit and the microcontroller. It boosts the excitation voltage generated by the power supply circuit according to the control signal of the microcontroller to form a first magnetic field that is higher than the reference magnetic field.

[0039] The microcontroller is used to receive the echo signal generated by the magnetostrictive sensor in the reference magnetic field, and to judge the echo signal. When the echo signal is less than the lower limit of the first preset range, it is judged to switch to the large range state; when the echo signal is greater than the upper limit of the first preset range, it is judged to switch to the small range state.

[0040] When switching to the large range state, the microcontroller boosts the excitation voltage and / or adjusts the echo signal gain by increasing the resistance of the first and second digital potentiometers, amplifying the echo signal and adjusting the large range so that the echo signal is within the large range range, and outputs the detection value.

[0041] When switching to the small range mode, the microcontroller only adjusts the echo signal gain. By reducing the resistance of the first and second digital potentiometers, the echo signal is reduced and the range is decreased, so that the echo signal is within the small range range and the detection value is output.

[0042] It should be noted that the microcontroller performs excitation voltage boosting and / or echo signal gain adjustment, including the following steps:

[0043] Initial detection: The program begins its measurement cycle, boost circuit ( Figure 1 Start stamping, digital potentiometer ( Figure 2 Set U16 / U19 as the default value.

[0044] When the signal is too weak: that is, the program does not detect a valid echo SIG, the boost circuit remains on, the digital potentiometer increases the gain of U16 and decreases the threshold of U19;

[0045] When the signal is too strong, the program receives a saturated and distorted signal, the boost circuit remains on, and the digital potentiometer reduces the gain of U16 and increases the threshold of U19.

[0046] When the test is completed: the program successfully receives the echo and performs the calculation, the boost circuit immediately shuts down the boost, and the digital potentiometer remains set. When entering intermittent standby, if the program has no test task for a long time: the boost circuit remains off, and the digital potentiometer enters low-power mode.

[0047] The adaptive signal conditioning circuit receives the echo signal gain adjustment signal from the microcontroller and changes the resistance values ​​of the first digital potentiometer and the second digital potentiometer.

[0048] like Figure 3 The power supply circuit is connected to the boost module; it adopts a single-transistor switching topology; and includes: a switching transistor, an energy storage inductor, a diode, a first energy storage capacitor C60, and a second energy storage capacitor C61.

[0049] One end of the energy storage inductor L5 is connected to the input power supply MP50, and the other end is connected to the collector of the switching transistor Q7 and the anode of the diode D26. The base of the switching transistor Q7 receives the pulse signal PULSE generated by the microcontroller, and its emitter is grounded. The cathode of the diode D26 is connected to one end of the first energy storage capacitor, one end of the second energy storage capacitor, and the high-voltage output terminal HPower. The other ends of the first and second energy storage capacitors are grounded. When PULSE is high, Q7 is turned on, and current flows through L5 to establish a magnetic field. When PULSE is low, Q7 is turned off, the magnetic energy stored in L5 is released, charging C60 and C61 to store energy, and outputting high voltage to HPower.

[0050] like Figure 4 The adaptive signal conditioning circuit includes a first-stage filter circuit, a two-stage programmable gain amplifier circuit, and a first-stage programmable threshold comparison circuit.

[0051] The first-stage filtering circuit is used to filter the received echo signal; that is, the capacitor C62 and the resistor R130 in the figure form a high-pass filter to filter the echo signal.

[0052] The input terminal of the two-stage programmable gain amplifier circuit is connected to the output terminal of the first-stage filter circuit. The gain of the two-stage programmable gain amplifier circuit is determined by the microcontroller adjusting the resistance value of the first digital potentiometer U16. Further, the two-stage programmable gain amplifier circuit includes a first operational amplifier U15, a second operational amplifier U17, and a feedback resistor network. The first operational amplifier U15 amplifies the filtered signal. The feedback resistor network is composed of the fixed terminal PB0 and the sliding terminal PW0 of the first digital potentiometer U16 connected in parallel, and then connected in series with a fixed resistor R113. The fixed terminal APA0 of the digital potentiometer U16 is connected to the output terminal of the operational amplifier U17, and the other end of the series resistor network is connected to the negative input terminal of the operational amplifier U17 for secondary amplification.

[0053] The programmable threshold comparison circuit includes a comparator U20 and a second digital potentiometer. Its first input terminal is connected to the output terminal of the two-stage programmable gain amplifier circuit, and its input terminal is connected to the output terminal of the second digital potentiometer to generate a programmable reference voltage Vref.

[0054] More preferably, the microcontroller adjusts the first digital potentiometer U16 via the SPI bus to change the gain of the two-stage programmable gain amplifier circuit, thereby adapting to echo signals of different intensities.

[0055] More preferably, the microcontroller adjusts the resistance of the second digital potentiometer U19 via the same SPI bus to change the programmable reference voltage Vref, thereby adapting to the range of different echo signals.

[0056] More preferably, the microcontroller is configured to: after adjusting the first digital potentiometer U16 to change the gain, synchronously and in conjunction with adjusting the second digital potentiometer U19, so that the programmable reference voltage Vref is adapted to the amplified signal level.

[0057] Interface J6 receives the echo signal ReceiveEcho from the magnetostrictive sensor. Capacitor C62 and resistor R130 form a high-pass filter to filter the echo signal. The output of operational amplifier U15 is connected to the fixed terminal A (PA0) of digital potentiometer U16 (MCP41010-I / SN). The sliding terminal PW0 and the fixed terminal B (PB0) of the first digital potentiometer U16 are connected in parallel and then in series with a fixed resistor R113 (1.5kΩ). The other end of the fixed resistor R113 is connected in series with the negative input terminal of U17. Assuming the equivalent resistance of U16 is RU16 (SPI programmable range: 0-10kΩ), the gain of the second-stage operational amplifier is:

[0058]

[0059] Adjustable range: -20 times (RU16=0) to -2.6 times (RU16=10kΩ). U17 amplifies the signal in two stages. U16, R113, and R114 form the feedback resistor network for op-amp U17, achieving adjustable gain to adapt to different signal amplitudes. The output signal of U17, along with the programmable threshold voltage Vref output by digital potentiometer U19 (MCP41010-I / SN), undergoes threshold judgment via U20 (MAX9142). When U17 > Vref, U20 outputs a high level (SIG=1); when U17 < Vref, U20 outputs a low level (SIG=0). The amplified signal is output to the non-inverting input of U20. Digital potentiometer U19 can be programmed and its resistance value adjusted via the SPI interface. U19 is connected to the inverting input of U20. That is, U20 outputs a square wave signal recognizable by the microcontroller. Figure 2 This circuit uses dual digital potentiometers U16 and U19 to adjust their resistance values ​​via SPI programming, automatically adapting to magnetostrictive signals of different distances / intensities.

[0060] This application also includes a microcontroller that adaptively adjusts itself based on the received echo data according to the following formula:

[0061] Feature extraction is performed based on the echo signal, and the data features include signal amplitude FA, signal-to-noise ratio SNR, and number of times the threshold is exceeded T, etc.

[0062] The adaptive adjustment decision function F(X,Y) is set to indicate that the echo signal is optimal when the resistance of the first potentiometer is X and the resistance of the second potentiometer is Y.

[0063] The amplitude, signal-to-noise ratio, and number of times the threshold was exceeded during the optimal echo signal iterations, along with the resistance values ​​of potentiometers U16 and U19, are correlated and mapped to represent the optimal echo signal using the following formula.

[0064]

[0065] Based on the received echo signals, the data from previous data are filtered for similarity. When the amplitude, signal-to-noise ratio, and correlation function of the number of times the echo signal exceeds the threshold in any previous echo signal have the highest similarity to the current echo signal, the resistance value of the current echo signal is selected.

[0066] The resistance value is adaptively adjusted to approach the resistance value of the echo signal selected based on similarity through the following gradient change process.

[0067]

[0068] When the signal amplitude FA is small, the SNR is low, that is... Less than the reference amplitude If the SNR is less than the reference signal-to-noise ratio SNR', then the first adjustment gradient applies. Gradually increase the resistance of the first digital potentiometer and decrease the resistance of the second digital potentiometer;

[0069] When the amplitude is moderate but the SNR is low This indicates that the signal has been captured, but the noise level is high. The resistance of the first digital potentiometer is slowly increased according to the second adjustment gradient S2 to slightly increase the gain (making the signal more prominent) while simultaneously increasing the threshold (to suppress noise). The goal is to find the optimal balance between gain and threshold to maximize the SNR.

[0070] If the number of occurrences exceeds the threshold by more than 1, it indicates that the threshold setting is too low, causing noise or ringing phenomena and generating multiple spurious pulses. In this case, the threshold Vref should be increased until only one clean and stable high-level pulse is generated within the echo window.

[0071] The microcontroller will emit pulses multiple times and fine-tune the resistance values ​​of U16 and U19 according to the above rules. The adjustment step should gradually change from coarse adjustment (large steps) to fine adjustment (small steps). When the signal amplitude is stable within the target range, the SNR is higher than the preset threshold, and only one valid trigger occurs in several consecutive iterations, the parameters are considered to be optimal, and the adjustment process ends.

[0072] Further preferably, the system also includes a storage module; the storage module is configured with the optimal configuration parameters obtained after adaptive adjustment; the microcontroller is also configured to: before performing adaptive adjustment, first query whether there are matching historical configuration parameters in the non-volatile memory, and if so, directly call the historical configuration parameters to configure the system.

[0073] More preferably, the storage module stores multiple sets of optimal configuration parameters, each set of optimal configuration parameters being associated with a specific detection component identifier and the current working timestamp;

[0074] The microcontroller is configured to select and load a corresponding set of configuration parameters from the plurality of sets of parameters based on user input or automatically identified probe component identifiers.

[0075] like Figure 5 The present invention also provides a magnetostriction detection method based on adaptive signal conditioning, implemented based on the above-mentioned magnetostriction detection system based on adaptive signal conditioning, comprising the following steps:

[0076] S1. Automatic reset is performed after power-on. During the automatic reset, the microcontroller sets the digital potentiometer to the middle value and controls the PWM pin to reset to the reference voltage.

[0077] S2. Based on the reference voltage, the boost module of the power supply circuit is in the off state, and the power supply circuit emits a reference pulse to form a reference magnetic field.

[0078] S3. Acquire the echo signal generated by the magnetostrictive sensor in the reference magnetic field, and judge the echo signal. When the echo signal is less than the lower limit of the first preset range, it is judged to switch to the large range state; when the echo signal is greater than the upper limit of the first preset range, it is judged to switch to the small range state.

[0079] S4. When switching to the large range state, the microcontroller boosts the excitation voltage and / or adjusts the echo signal gain by increasing the resistance values ​​of the first and second digital potentiometers to adjust the large range, so that the echo signal is within the large range range and outputs the detection value.

[0080] When switching to the small range mode, the microcontroller only adjusts the echo signal gain. By reducing the resistance of the first and second digital potentiometers, the range is reduced, so that the echo signal is within the small range and the detection value is output.

[0081] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A magnetostriction detection system based on adaptive signal conditioning, comprising a power supply circuit, a boost module, an adaptive signal conditioning circuit, and a microcontroller; The power supply circuit is used to generate an excitation voltage to generate a reference magnetic field for magnetostriction. The boost module is connected to the power supply circuit and the microcontroller. It boosts the excitation voltage generated by the power supply circuit according to the control signal of the microcontroller to form a first magnetic field that is higher than the reference magnetic field. The microcontroller is used to receive the echo signal generated by the magnetostrictive sensor in the reference magnetic field, and to judge the echo signal. When the echo signal is less than the lower limit of the first preset range, it is judged to switch to the large range state; when the echo signal is greater than the upper limit of the first preset range, it is judged to switch to the small range state. When switching to the large range state, the microcontroller boosts the excitation voltage and / or adjusts the echo signal gain by increasing the resistance of the first and second digital potentiometers, amplifying the echo signal and adjusting the large range so that the echo signal is within the large range range, and outputs the detection value. When switching to the small range mode, the microcontroller only adjusts the echo signal gain. By reducing the resistance of the first and second digital potentiometers, the echo signal is reduced and the range is decreased, so that the echo signal is within the small range range and the detection value is output. The adaptive signal conditioning circuit receives the echo signal gain adjustment signal from the microcontroller and changes the resistance values ​​of the first digital potentiometer and the second digital potentiometer.

2. The magnetostriction detection system based on adaptive signal conditioning according to claim 1, characterized in that, The power supply circuit is connected to the boost module; It adopts a single-transistor switching topology; including: a switching transistor, an energy storage inductor, a diode, a first energy storage capacitor, and a second energy storage capacitor; One end of the energy storage inductor is connected to the input power supply, and the other end is connected to the collector of the switching transistor and the anode of the diode; the base of the switching transistor receives the pulse signal ULSE generated by the microcontroller and the emitter is grounded; the cathode of the diode is connected to one end of the first energy storage capacitor, one end of the second energy storage capacitor, and the high-voltage output terminal HPower, and the other ends of the first energy storage capacitor and the second energy storage capacitor are grounded.

3. The magnetostriction detection system based on adaptive signal conditioning according to claim 1, characterized in that, The adaptive signal conditioning circuit includes a first-stage filter circuit, a two-stage programmable gain amplifier circuit, and a first-stage programmable threshold comparison circuit. The first-stage filter circuit is used to filter the received echo signal; the input terminal of the two-stage programmable gain amplifier circuit is connected to the output terminal of the first-stage filter circuit, and the gain of the two-stage programmable gain amplifier circuit is determined by the microcontroller adjusting the resistance value of the first digital potentiometer. The programmable threshold comparison circuit includes a comparator and a second digital potentiometer. Its first input terminal is connected to the output terminal of the two-stage programmable gain amplifier circuit, and its input terminal is connected to the output terminal of the second digital potentiometer to generate a programmable reference voltage Vref.

4. The magnetostriction detection system based on adaptive signal conditioning according to claim 3, characterized in that, The two-stage programmable gain amplifier circuit includes a first operational amplifier, a second operational amplifier, and a feedback resistor network. The first operational amplifier amplifies the filtered signal. The feedback resistor network is composed of a fixed terminal and a sliding terminal of a first digital potentiometer connected in parallel, and then connected in series with a fixed resistor. The fixed terminal of the first digital potentiometer is connected to the output terminal of the second operational amplifier, and the other end of the series resistor network is connected to the negative input terminal of the second operational amplifier for two-stage amplification.

5. The magnetostriction detection system based on adaptive signal conditioning according to claim 4, characterized in that, The microcontroller adjusts the first digital potentiometer via the SPI bus to change the gain of the two-stage programmable gain amplifier circuit, thereby adapting to echo signals of different intensities.

6. The magnetostriction detection system based on adaptive signal conditioning according to claim 5, characterized in that, The microcontroller adjusts the resistance of the second digital potentiometer via the same SPI bus to change the programmable reference voltage Vref, thereby adapting to the range of different echo signals.

7. The magnetostriction detection system based on adaptive signal conditioning according to claim 6, characterized in that, The microcontroller is configured to: after adjusting the first digital potentiometer to change the gain, synchronously and in conjunction with adjusting the second digital potentiometer, so that the programmable reference voltage Vref is adapted to the amplified signal level.

8. The magnetostriction detection system based on adaptive signal conditioning according to claim 6, characterized in that, It also includes a storage module; the storage module is configured with the optimal configuration parameters obtained after adaptive adjustment; the microcontroller is further configured to: before performing adaptive adjustment, first query whether there are matching historical configuration parameters in the non-volatile memory, and if so, directly call the historical configuration parameters to configure the system.

9. The magnetostriction detection system based on adaptive signal conditioning according to claim 8, characterized in that, The storage module stores multiple sets of optimal configuration parameters, each set of optimal configuration parameters being associated with a specific detection component identifier and the current working timestamp; The microcontroller is configured to select and load a corresponding set of optimal configuration parameters from the plurality of sets based on user input or automatically identified detector component identifiers.

10. A magnetostriction detection method based on adaptive signal conditioning, implemented based on the magnetostriction detection system based on adaptive signal conditioning according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Automatic reset is performed after power-on. During the automatic reset, the microcontroller sets the digital potentiometer to the middle value and controls the PWM pin to reset to the reference voltage. S2. Based on the reference voltage, the boost module of the power supply circuit is in the off state, and the power supply circuit emits a reference pulse to form a reference magnetic field. S3. Acquire the echo signal generated by the magnetostrictive sensor in the reference magnetic field, and judge the echo signal. When the echo signal is less than the lower limit of the first preset range, it is judged to switch to the large range state; when the echo signal is greater than the upper limit of the first preset range, it is judged to switch to the small range state. S4. When switching to the large range state, the microcontroller boosts the excitation voltage and / or adjusts the echo signal gain by increasing the resistance values ​​of the first and second digital potentiometers to adjust the large range, so that the echo signal is within the large range range and outputs the detection value. When switching to the small range mode, the microcontroller only adjusts the echo signal gain. By reducing the resistance of the first and second digital potentiometers, the range is reduced, so that the echo signal is within the small range and the detection value is output.

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