Method for monitoring density of cement paste in well cementation operation based on double-closed-loop cooperative control

Abstract

The invention provides a well cementation operation cement paste density monitoring method based on double-closed-loop cooperative control, and relates to the field of cement paste density monitoring, and the method specifically comprises the following steps: collecting an original signal of a sensor and an original signal of a driver; performing storage shift on the sensor signal and the driver signal, and judging whether the signals cross a zero point or not; if yes, the amplitudes of the sensor signal and the driving signal in one period are calculated, and the frequency of the sensor signal and the phases of the two signals are calculated; calculating phases of the driving gain increment signal and the driving signal; generating a composite driving signal fusing frequency, phase and amplitude information; and fitting a density-frequency model through a quadratic polynomial, and calculating the density of the measured cement paste on line by using the extracted fundamental frequency. According to the technical scheme, the defect that cement paste density calculation errors are increased in the prior art is overcome; resonance drift caused by change of working conditions cannot be handled, so that unstable vibration of the measuring tube is caused, and the measuring precision is further influenced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of cement slurry density monitoring, in particular to a cementing operation cement slurry density monitoring method based on double closed-loop cooperative control. BACKGROUND

[0002] Cementing operation is a key process of oil and gas exploitation, and cement slurry density is a core parameter that determines the quality of cementing and the safety of wellbore. Whether it can be accurately and timely monitored directly relates to the safety of the operation and the long-term stability of oil and gas wells. If the density is too low, it is easy to cause blowout, annular channeling and other serious accidents, and if the density is too high, it may fracture the formation and cause insufficient annular filling, resulting in huge economic losses. The traditional offline density measurement method (such as specific gravity bottle and laboratory densimeter) has a measurement period of more than 10 minutes, which cannot cope with the dynamic fluctuations of cement slurry density in deep well and ultra-deep well operations, and is easy to miss the control window; radioactive density instruments have radiation safety risks and complex maintenance, which are difficult to meet the continuous operation requirements of cementing operation.

[0003] The vibrating tube density meter (VTD) is based on the inherent coupling relationship between the measurement tube's natural vibration frequency and the density, realizes online measurement of fluid density, and has the core advantages of simple structure, high measurement accuracy and non-contact measurement, which is an ideal technical solution for real-time monitoring of cement slurry density in cementing operation. However, the cementing wellhead working condition is extremely harsh: the cement slurry viscosity is as high as 500~2000mPa・s, the solid particle content is more than 20%, and it is also faced with 10~120MPa high pressure, strong mechanical vibration (piping vibration caused by mud pump) and electromagnetic interference, which poses a severe challenge to the stability and adaptability of the VTD driving system.

[0004] The existing VTD driving system has certain limitations: on the one hand, the signal processing accuracy is insufficient, the traditional time / frequency domain analysis method is easily affected by speed fluctuation and environmental interference, and it is difficult to accurately extract the frequency, amplitude and phase difference of the vibration signal, which leads to an increase in density calculation error; on the other hand, the control strategy is single, most driving systems only use simple amplitude control, lack of accurate compensation for phase difference, and cannot cope with the resonance drift caused by working condition changes, which leads to unstable vibration of the measurement tube and further affects the measurement accuracy. In addition, the analog driving system has inherent defects such as difficult start and weak anti-electromagnetic interference ability, and the existing digital driving system has insufficient cooperation between the parameter extraction algorithm and the control strategy, and limited working condition adaptability.

[0005] Therefore, there is a need for a cementing operation cement slurry density monitoring method based on double closed-loop cooperative control, which can accurately extract parameters under complex working conditions and has high density measurement accuracy. SUMMARY

[0006] The main purpose of the present application is to provide a cementing operation cement slurry density monitoring method based on double closed-loop cooperative control, so as to solve the problem that in the prior art, it is difficult to accurately extract the frequency, amplitude and phase difference key parameters of the vibration signal, resulting in increased density calculation error; unable to cope with the resonance drift caused by the working condition change, resulting in unstable measurement tube vibration, further affecting the measurement accuracy.

[0007] To achieve the above purpose, the present application provides a cementing operation cement slurry density monitoring method based on double closed-loop cooperative control, which specifically comprises the following steps: S1, after measuring the vibration of the measuring tube, the sensor original signal and the driver original signal are collected, and the abnormal values are removed.

[0008] S2, the sensor signal and the driver signal are stored and shifted, and whether the signal passes through the zero point is judged according to the changes before and after the signal respectively; if yes, the amplitude of the sensor signal and the driving signal in a period is calculated, the frequency of the sensor signal and the phase difference of the two signals are calculated, and then step S3 is executed; if not, the sensor signal and the driver signal of the next point are continuously collected, and step S2 is continuously executed until the signal zero crossing point is detected.

[0009] S3, according to the sensor signal amplitude, the driving gain increment signal is calculated according to the PID operation rule; according to the phase difference between the sensor and the driver, the phase compensation amount is calculated according to the PID operation rule.

[0010] S4, the extracted frequency and phase difference are transmitted to the direct digital synthesizer DDS, the driving amplitude gain and the sine signal with specified frequency and phase generated by the DDS are transmitted to the multiplication digital-to-analog converter MDAC, and the composite driving signal integrating the frequency, phase and amplitude information is generated.

[0011] S5, the measured cement slurry density is calculated online by using the extracted fundamental frequency through quadratic polynomial fitting density-frequency model.

[0012] Further, step S1 specifically comprises the following steps: S1.1, collecting the sensor original signal and the driver original signal at the moment.

[0013] S1.2, removing the sensor signal abnormal value: ; Wherein, is the sensor signal value after removing the abnormal value at the moment, the initial value , is the upper limit value of the sensor signal.

[0014] S1.3, remove the abnormal value of driver signal: ; wherein, is the abnormal value of driver signal at time t, and the initial value is 0 V; , is the upper limit value of driver signal.

[0015] Further, step S2 specifically comprises the following steps: S2.1, perform storage shift of sensor signal: ; ; ; ; wherein, is the sensor signal value at time t, and the initial value is 0 V; is the sensor signal value at time t, and the initial value is 0 V; is the sensor signal value at time t, and the initial value is 0 V; is the sensor signal value at time t, and the initial value is 0 V; is the sensor signal value at time t, and the initial value is 0 V.

[0016] S2.2, perform storage shift of driver signal: ; ; ; ; wherein, is the driver signal value at time t, and the initial value is 0 V; is the driver signal value at time t, and the initial value is 0 V; is the driver signal value at time t, and the initial value is 0 V; is the driver signal value at time t, and the initial value is 0 V; is the driver signal value at time t, and the initial value is 0 V.

[0017] S2.3, update the maximum value of sensor signal : ; wherein, is the maximum value function.

[0018] S2.4, update the minimum value of sensor signal : ;​​​​​​​ wherein, is a minimum value function.

[0019] Further, step S2 also comprises the following steps: S2.5, if the sensor signal satisfies the condition then calculate the number of times of zero-crossing of the sensor signal : ; wherein, the initial value of is set to 0.

[0020] calculate the sampling count value corresponding to the previous zero-crossing time of the sensor : ; wherein, the initial value of is set to 0.

[0021] calculate the sampling count value corresponding to the current zero-crossing time of the sensor : ; wherein, the initial value of is set to 0.

[0022] S2.6, calculate the number of sampling points between the adjacent two zero-crossing points of the sensor signal : ; calculate the interpolation correction value corresponding to the current zero-crossing time of the sensor : ; wherein, the initial value is set to 0.

[0023] assign the interpolation correction value corresponding to the current zero-crossing time of the sensor to the interpolation correction value corresponding to the previous zero-crossing time of the sensor : ; wherein, the initial value is set to 0.

[0024] S2.7, update the sensor signal frequency value : ; wherein, is the signal sampling frequency.

[0025] S2.8, update the phase difference value of the driver signal and the sensor signal : ; wherein, is the sampling period; the initial value of is set to 0; if , let normalize to [-180°, 180°].

[0026] S2.9, update the sensor signal amplitude : ; calculate the amplitude deviation ; set the value of the amplitude of the vibrating tube.

[0027] Further, step S3 comprises the following steps: S3.1, calculate the phase difference deviation at the current time: ; wherein, the initial value is set to 0°; set the value of the phase difference, which is 0°.

[0028] assign the phase difference deviation at the current time to the phase deviation of the driver and the sensor at the last time: ; wherein, the initial value is set to 0°; generate the phase compensation amount using a PI controller : ; wherein, , are the proportional and integral coefficients of the phase difference PI controller, respectively;

[0029] wherein, and are the upper and lower limit values of the phase compensation amount, respectively.

[0030] assign the phase compensation amount at the current time to the phase compensation amount at the last time : ; wherein, is the phase compensation amount at the current time, the initial value of which is set to 0°, the initial value is set to 0°.

[0031] S3.2, according to the size of match different proportional coefficients With integral coefficient : ; in, and These represent the high and low threshold values ​​for amplitude deviation, respectively. , These are the high deviation proportional and integral coefficients of the amplitude PI controller, respectively. , These are the proportional and integral coefficients of the amplitude PI controller, respectively; These are the low-deviation proportional and integral coefficients of the amplitude PI controller, respectively.

[0032] S3.3, Calculate the incremental signal of the driving gain: ; in, The amplitude deviation at the current moment is initially set to 0V; The initial value is set to 0V to represent the amplitude deviation from the previous moment. This represents the amplitude gain increment.

[0033] Assign the current amplitude deviation to the previous amplitude deviation. : .

[0034] S3.4, Calculate the driving amplitude gain : ; in, and These are the upper and lower limits of the drive gain, respectively.

[0035] S3.5, if the sensor signal does not meet the conditions Then proceed to step S4.

[0036] Furthermore, step S4 specifically includes the following steps: The DDS phase is updated based on the fusion frequency and phase compensation amount to generate a sinusoidal signal. : ; calculate The sinusoidal signal output by the DDS at any given time : .

[0037] Multiply the DDS output signal by the amplitude gain to synthesize. Moment drive signal : ; The MDAC output signal is amplified to obtain a driving signal : ; wherein, is the power amplifier amplification factor.

[0038] Further, the step S5 is specifically: calculating the density of the sampling time : ; wherein, , , is the model coefficient.

[0039] The present application has the following beneficial effects: The purpose of the present application is to provide a "signal processing-double closed loop collaborative control-density calculation" integrated digital driving system, through the collaborative design of high-precision signal processing algorithm and double closed loop control strategy, the parameter extraction accuracy, vibration stability and density measurement accuracy of the vibrating tube densitometer under complex cementing working conditions are improved, and the real-time online monitoring demand of the cement slurry density is met. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the specific embodiments or prior art description will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor. In the drawings: Figure 1 The figure shows the principle diagram of the vibrating tube densitometer digital driving system based on double closed loop collaborative control of the second embodiment of the present application. DETAILED DESCRIPTION

[0041] The technical solutions of the present application will be described below in conjunction with the drawings, obviously, the described embodiments are some of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0042] Embodiment one A monitoring method for cementing operation cement slurry density based on double closed loop collaborative control, defining the sensor and driver signal sampling frequency as (unit: Hz) (example value Hz), sampling period , is a discrete sampling time, denotes the initial time. The following steps are performed starting from the sampling time k = 1, and specifically include the following steps: S1, after measuring the tube vibration, collect the sensor original signal and the driver original signal, and eliminate abnormal values; wherein the driver is used to drive the densimeter measuring tube (vibration tube) to resonate.

[0043] S2, store and shift the sensor signal and the driver signal, and respectively judge whether the signal passes zero point according to the changes before and after the signal; if yes, calculate the amplitude of the sensor signal and the driving signal within a period, calculate the frequency of the sensor signal and the phase difference between the two signals, and then perform step S3; if not, continue to collect the sensor signal and the driver signal of the next point, and continue to perform step S2 until the signal passes zero point.

[0044] S3, according to the amplitude of the sensor signal, calculate the driving gain increment signal according to the PID operation rule; according to the phase difference between the sensor and the driver, calculate the phase compensation according to the PID operation rule.

[0045] S4, transmit the extracted frequency and phase difference to the direct digital synthesizer DDS, and transmit the driving amplitude gain and the sine signal with specified frequency and phase generated by the DDS to the multiplying digital-to-analog converter MDAC. The DDS generates a sine signal with specified frequency and phase; the MDAC multiplies the analog input signal (i.e. the DDS output signal) with the digital input signal (i.e. the amplitude gain), to generate a composite driving signal that integrates frequency, phase and amplitude information. After being amplified by the power amplifier, the composite signal is used to drive the measuring tube to vibrate.

[0046] S5, by fitting the density-frequency model with a quadratic polynomial, the measured cement slurry density is calculated online using the extracted fundamental frequency.

[0047] Specifically, it is characterized in that step S1 specifically includes the following steps: S1.1, collect the sensor original signal and the driver original signal at time t0.

[0048] S1.2, eliminate abnormal values of the sensor signal: ; wherein, is the sensor signal value after eliminating abnormal values at time t0(unit: V), the initial value , is the upper limit of the sensor signal, and a value beyond the range is determined as an abnormal value (for example, 5v).

[0049] S1.3, remove abnormal values of the driver signal: ; wherein, is the abnormal value of the driver signal at the moment (unit: V), and the initial value is 0V. , is the upper limit of the driver signal, and a value beyond the range is determined as an abnormal value (for example, 5v).

[0050] Specifically, step S2 specifically comprises the following steps: S2.1, perform sensor signal storage shift: ; ; ; ; wherein, is the sensor signal value at the moment, and the initial value is 0V. is the sensor signal value at the moment, and the initial value is 0V. is the sensor signal value at the moment, and the initial value is 0V. is the sensor signal value at the moment, and the initial value is 0V. is the sensor signal value at the moment, and the initial value is 0V.

[0051] S2.2, perform driver signal storage shift: ; ; ; ; wherein, is the driver signal value at the moment, and the initial value is 0V. is the driver signal value at the moment, and the initial value is 0V. is the driver signal value at the moment, and the initial value is 0V. is the driver signal value at the moment, and the initial value is 0V. is the driver signal value at the moment, and the initial value is 0V.

[0052] S2.3, update the maximum value of the sensor signal : ; wherein, ​​​​​​​is a maximum function, The initial value is set to 0.1 V.

[0053] S2.4, update the minimum value of the sensor signal : ; wherein, is a minimum function, The initial value is set to -0.1 V.

[0054] Specifically, step S3 specifically comprises the following steps: S2.5, if the sensor signal satisfies the condition , then calculate the number of times of zero-crossing of the sensor signal : ; wherein, The initial value of is set to 0.

[0055] Calculate the sampling count value corresponding to the previous zero-crossing time of the sensor : ; wherein, The initial value of is set to 0; (dimensionless).

[0056] Calculate the sampling count value corresponding to the current zero-crossing time of the sensor : ; wherein, The initial value of is set to 0; (dimensionless)

[0057] S2.6, calculate the number of sampling points between the adjacent two zero-crossing points of the sensor signal : .

[0058] Calculate the interpolation correction value corresponding to the current zero-crossing time of the sensor : ; wherein, The initial value is set to 0 (dimensionless, range [0, 1]).

[0059] Assign the interpolation correction value corresponding to the current zero-crossing time of the sensor to the interpolation correction value corresponding to the previous zero-crossing time of the sensor : ; wherein, The initial value is set to 0 (dimensionless, range [0, 1]).

[0060] S2.7, update the sensor signal frequency value (unit: Hz): ; wherein, is the signal sampling frequency.

[0061] S2.8, update the driver signal and sensor signal phase difference value (unit: °): ; wherein, is the sampling period; the initial value is set to 0.

[0062] if , let normalize to [-180°, 180°].

[0063] S2.9, update the sensor signal amplitude value (unit: V): ; calculate the amplitude deviation ; is the vibration tube amplitude set value.

[0064] Specifically, step S3 includes the following steps: S3.1, calculate the current time phase difference deviation: ; wherein, the initial value is set to 0°, and the difference between the phase difference set value and the actual phase difference; is the phase difference set value, which is set to 0°.

[0065] assign the current time phase difference deviation to the previous time driver and sensor phase deviation (i.e., driver phase minus sensor phase): ; wherein, the initial value is set to 0°, and the difference between the phase difference set value and the actual phase difference.

[0066] generate a phase compensation amount using a PI controller : ; wherein, , are the proportional and integral coefficients of the phase difference PI controller, respectively, which are set to 0.3 and 0.1 in the embodiment.

[0067]

[0068] in, and These are the upper and lower limits of the phase compensation amount, respectively.

[0069] Assign the current phase compensation value to the previous phase compensation value. : ; in, This is the phase compensation amount at the current moment, with an initial value set to 0°. It is used to adjust the phase of the drive signal to match the sensor signal. The initial value is set to 0°, which is used to adjust the phase of the drive signal to match the sensor signal.

[0070] S3.2, according to Size, matching different scaling factors With integral coefficient : ; in, and These represent the high and low threshold values ​​for amplitude deviation, respectively. , These are the high deviation proportional and integral coefficients of the amplitude PI controller, respectively, which are set to 5 and 2 in this embodiment; , These are the proportional deviation and integral coefficient of the amplitude PI controller, respectively, and in this embodiment they are set to 3 and 1, respectively; These are the low deviation proportional and integral coefficients of the amplitude PI controller, respectively, and in this embodiment, they are set to 1 and 0.5, respectively.

[0071] S3.3, Calculate the incremental signal of the driving gain: ; in, The amplitude deviation at the current moment is initially set to 0V, which is the difference between the preset amplitude and the actual amplitude. The amplitude deviation at the previous moment is initially set to 0V, which is the difference between the preset amplitude and the actual amplitude. This is the amplitude gain increment, initially set to 0, used to update the amplitude gain.

[0072] Assign the current amplitude deviation to the previous amplitude deviation. For use in the next iteration calculation: .

[0073] S3.4, Calculate the driving amplitude gain : ; wherein, and are the upper and lower limit values of the drive gain, respectively; The initial value is set to 1.0 (dimensionless) for adjusting the amplitude of the drive signal.

[0074] S3.5, if the sensor signal does not satisfy the condition Step S4 is performed.

[0075] Specifically, step S4 specifically comprises the following steps: updating the DDS phase based on the fusion frequency and the phase compensation amount to generate a sinusoidal signal : ; wherein, is the phase of the DDS at time k (unit: rad).

[0076] calculating the sinusoidal signal output by the DDS at time k : ; dimensionless, range [-1, 1].

[0077] multiplying the DDS output signal by the amplitude gain to synthesize drive signal at time k : ; amplifying the MDAC output signal to obtain the drive signal : ; wherein, is the amplification factor of the power amplifier, used to amplify the drive signal.

[0078] Specifically, step S5 specifically comprises: calculating the density of the sampling time : ; wherein, , , are model coefficients.

[0079] In the field test of the vibration pipe densitometer matched with the cementing pump in an oilfield, the method provided by the application is used for online monitoring of the cement slurry density, and the experimental conditions and results are as follows: 1. Experimental conditions ​​Environmental conditions: room temperature (25±1℃); Test medium: 6 kinds of medium covering the density range of commonly used cementing slurry, including seawater (1.02 g / cm³), 2 kinds of low-density cementing slurry (LD-LC1: 1.18 and LD-LC2: 1.21 g / cm³), 2 kinds of medium-density cementing slurry (MD-LC1: 1.38 and MD-LC2: 1.45 g / cm³), and 1 kind of high-density cementing slurry (HD-LC: 1.90 g / cm³); System parameters: sensor sampling frequency 16 kHz, DDS 16 bits (frequency resolution 0.01 Hz), and MDAC 12 bits (to ensure the accuracy of gain adjustment).

[0080] 2. Test results Signal extraction accuracy: frequency extraction error ≤±0.01 Hz, amplitude extraction steady-state error ≤±0.01 V, and phase difference steady-state fluctuation ≤±0.1°; Closed-loop control performance: when the test medium is switched (such as seawater→low-density cementing slurry→high-density cementing slurry), the phase difference is restored to the set value within 1 s, the amplitude fluctuation range is ≤±0.1 V, and the frequency tracking response time is ≤1 s (without overshoot). Density measurement accuracy: as shown in Table 1, the absolute error of the density measurement of the cementing slurry is all ≤0.005 g / cm³, meeting the accuracy requirement of density monitoring for cementing operations.

[0081] Table 1. Density measurement values and errors

[0082] Working condition adaptability: in the test of simulating high-viscosity (1500 mPa·s) and high-solid-phase (20% particle content) cementing slurry, the system can still operate stably, the density measurement error does not increase significantly, and the anti-interference ability is significantly better than that of the traditional driving system.

[0083] The method provided by the application has excellent parameter extraction accuracy, closed-loop control stability and density measurement accuracy in field tests, can adapt to complex working conditions of cementing operations, effectively solves the technical bottleneck of the traditional driving system, provides a reliable technical solution for real-time online monitoring of cement slurry density, and has been successfully applied to cementing operations of 3 deep wells with a cumulative operation time of more than 1000 hours without any problem of shutdown or measurement accuracy exceeding the standard.

[0084] Example 2 As Figure 1As shown, the application also provides a double closed-loop cooperative control based digital driving system for vibrating tube density meter. The working principle of the system is as follows: after the measurement tube is vibrated, the sensor signal is collected and the signal amplitude, frequency and driver-sensor phase difference are extracted online through signal processing algorithm. The frequency signal is mapped to the corresponding density value through the density-frequency model; the amplitude signal is fed back to the adaptive amplitude controller to generate the driving amplitude gain, ensuring that the measurement tube maintains stable vibration at the preset amplitude set value; the phase difference signal is fed back to the phase difference controller to match the phase of the driving output and the sensor signal, ensuring that the driving signal can maintain the resonance of the measurement tube with the highest energy efficiency and avoid vibration attenuation or instability caused by phase mismatch. Finally, the extracted frequency and the compensation phase output by the phase difference controller are transmitted to the direct digital synthesizer (DDS), and the amplitude gain is transmitted to the multiplication digital-to-analog converter (MDAC). The DDS generates a sine signal with specified frequency and phase; the MDAC multiplies the analog input signal (i.e. the DDS output signal) and the digital input signal (i.e. the amplitude gain) to generate a composite driving signal that integrates frequency, phase and amplitude information. After being amplified by the power amplifier, the composite signal is used to drive the measurement tube to vibrate.

[0085] Of course, the above description is not a limitation of the application, and the application is not limited to the above examples. Changes, modifications, additions or substitutions made by those skilled in the art within the scope of the application should also be within the scope of the application.

Claims

1. A method for monitoring cement slurry density in cementing operation based on double closed-loop cooperative control, characterized in that, Specifically comprising the following steps: S1, after measuring the pipe vibration, collecting the sensor original signal and the driver original signal, and eliminating abnormal values; S2, storing and shifting the sensor signal and the driver signal, and judging whether the signal is zero point according to the changes before and after the signal respectively; if yes, calculating the amplitude of the sensor signal and the driving signal in a period, calculating the frequency of the sensor signal and the phase difference of the two signals, and then executing step S3; if not, continue to collect the sensor signal and the driver signal of the next point, and continue to execute step S2 until the signal zero point is detected; S3, according to the sensor signal amplitude, calculating the driving gain increment signal according to the PID operation rule; according to the phase difference between the sensor and the driver, calculating the phase compensation according to the PID operation rule; S4, transmitting the extracted frequency and phase difference to the direct digital synthesizer DDS, transmitting the driving amplitude gain and the sine signal with specified frequency and phase generated by DDS to the multiplication digital analog converter MDAC, and generating the composite driving signal integrating the frequency, phase and amplitude information; S5, through the quadratic polynomial fitting density-frequency model, the extracted base frequency is used to calculate the measured cement slurry density online.

2. The method of claim 1, wherein the method is characterized by, Step S1 specifically comprises the following steps: S1.1, acquisition time sensor raw signal with driver raw signal ; S1.2, eliminating the abnormal values of the sensor signal: ； wherein is the sensor signal value after removing outliers at the moment, initial value , is the upper limit value of the sensor signal; S1.3, eliminating the abnormal values of the driver signal: ； wherein, is the driver signal at the moment of removing the outlier, the initial value , is the upper limit value of the driver signal.

3. The method of claim 1, wherein the method is characterized by: Step S2 specifically comprises the following steps: S2.1, storing and shifting the sensor signal: ; ; ; ； wherein, is the sensor signal value at the time instant, with an initial value of 0 V; is the sensor signal value at the time instant, with an initial value of 0 V; is the sensor signal value at the time instant, with an initial value of 0 V; is the sensor signal value at the time instant, with an initial value of 0 V; S2.2, storing and shifting the driver signal: ; ; ; ; wherein, is the driver signal value at time t, with an initial value of 0 V; is the driver signal value at time t, with an initial value of 0 V; is the driver signal value at time t, with an initial value of 0 V; is the driver signal value at time t, with an initial value of 0 V; S2.3, update sensor signal maximum value : ； wherein is a max function; S2.4, update sensor signal minimum value : ; wherein is the minimum function.

4. The method according to claim 3, wherein, Step S2 further comprises the following steps: S2.5, if the sensor signal satisfies the condition then calculate the number of zero-crossings of the sensor signal : ； wherein, the initial value of is set to 0; calculating a sampling count value corresponding to a previous zero-crossing time of the sensor : ； wherein, the initial value of is set to 0; calculating a sampling count value corresponding to a current zero-crossing time of the sensor : ； wherein, the initial value of is set to 0; S2.6, calculate the number of sampling points between two adjacent zero-crossings of the sensor signal : ； calculating an interpolated correction value corresponding to a current zero-crossing time of the sensor : ； wherein, Initial value is 0; assigning the interpolation correction value corresponding to the current zero-crossing time of the sensor to the interpolation correction value corresponding to the previous zero-crossing time of the sensor : ； wherein, Initial value is 0; S2.7, updating the sensor signal frequency value : ； wherein is the signal sampling frequency; S2.8, updating the drive signal and sensor signal phase difference value : ； wherein is a sampling period; the initial value of is set to 0; If then let normalize to [-180°, 180°]; S2.9, update sensor signal amplitude : ； Calculate amplitude deviation ; Set the amplitude value for the vibrating tube.

5. The method of claim 1, wherein the method is characterized by: Step S3 comprises the following steps: S3.1, calculating the phase difference deviation at the current time: ； wherein The initial value is set to 0°. The value for the phase difference is set to 0°. Assigning the phase difference deviation at the current time to the phase deviation of the driver and the sensor at the last time: ； wherein, Initial value is set to 0°; Generating phase compensation with a pi controller : ； wherein, , are the proportional and integral coefficients of the phase difference PI controller, respectively. ； wherein and are the upper and lower limit values of the phase compensation, respectively; assigning a current time phase compensation amount to a previous time phase compensation amount : ； wherein, is the phase compensation amount for the current time instant, with an initial value of 0°, with an initial value of 0°; S3.2, according to Size, match different scale factors With integral coefficient : ； wherein, and are high, low amplitude deviation thresholds, respectively, , are high deviation proportional, integral coefficients of the amplitude PI controller, respectively; , are medium deviation proportional, integral coefficients of the amplitude PI controller, respectively; are low deviation proportional, integral coefficients of the amplitude PI controller, respectively. S3.3, calculating the driving gain increment signal: ； Wherein, is the current time amplitude deviation, the initial value is set to 0V; is the last time amplitude deviation, the initial value is set to 0V; is the amplitude gain increment; assigning the amplitude deviation of the current time instant to the amplitude deviation of the previous time instant : ； S3.4, compute drive amplitude gain : ； wherein and are the upper and lower drive gain limit values, respectively; S3.5, if the sensor signal does not satisfy the condition then step S4 is performed.

6. The method of claim 1, wherein the method is characterized by: Step S4 specifically comprises the following steps: Updating the DDS phase based on the fusion frequency and phase compensation amount to generate a sinusoidal signal : ； Computing the sine signal outputted by the DDS at the moment : ； The DDS output signal is multiplied by an amplitude gain to synthesize the moment driving signal : ； The MDAC output signal Amplification to obtain a drive signal : ； wherein PAM is the power amplifier multiplication factor.

7. The method of claim 1, wherein the method is characterized by: Step S5 specifically is: Computing the sampling instants Density of the instants : ; wherein , , are model coefficients.

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