A flow adaptive compensation control method for a fluid delivery object

Abstract

The application relates to the technical field of fluid regulation, and discloses a flow adaptive compensation control method for a fluid conveying object, which comprises the following steps: obtaining a rated flow given value of a flow regulation loop, superimposing a carrier excitation signal of a preset frequency, outputting a combined excitation signal to a flow regulation execution unit, exciting a perturbation fluctuation signal carrying dynamic physical characteristics in a fluid pipeline, collecting a feedback flow signal in real time and extracting a same-frequency response component, calculating a response transmission ratio representing a physically effective bandwidth of the controlled pipeline, reconstructing a regulation gain of a flow adaptive control law according to the numerical fluctuation of the response transmission ratio, correcting the rated flow given value by using the regulation gain, and outputting a flow compensation instruction to the flow regulation execution unit. The application establishes a coupling mechanism of the control law and the pipeline physical constraint, effectively solves the regulation deviation caused by the viscosity drift of the fluid, and eliminates the pump body surge or dynamic pressure shock fluctuation induced by the regulation overshoot.

Description

Technical Field

[0001] This invention relates to a flow adaptive compensation control method for fluid transport objects, belonging to the field of fluid regulation technology. Background Technology

[0002] The closed-loop feedback mechanism using proportional-integral-derivative (PID) controllers is a common technique. It uses a flow meter to collect feedback signals and compares them with the flow setpoint to generate a control signal to drive the pumping actuator, thus achieving stable flow regulation. This control method based on deviation elimination has good reliability under relatively constant physical characteristics. However, when the conveying conditions change, the fluid medium often exhibits fluctuations in physical characteristics. For example, in fine chemical production, the fluid viscosity changes nonlinearly with ambient temperature, or back pressure interference occurs due to deposits on the inner wall of the pipeline. Existing regulation methods are limited by statically calibrated parameter models, making it difficult to detect changes in the current dynamic impedance of the fluid conveying system, resulting in a mismatch between the control output of the actuator and the actual impedance state of the physical system.

[0003] To address the aforementioned interference, increasing the controller gain to enhance compensation strength introduces new physical constraints. In high-viscosity environments, there is a phase lag between the execution of the adjustment action and the fluid's physical response. Blindly increasing the gain often leads the system into a nonlinear oscillation range. Another approach is to install pressure sensors or viscosity probes to construct a multivariate observation system. However, this not only increases the difficulty of hardware integration, but also makes external probes prone to measurement deviations due to material adhesion in corrosive and crystalline fluid environments. In the field of flow control, there is still a lack of an effective method to directly detect and invert the physical impedance characteristics of the system. For example, Chinese invention patent CN110462269B discloses a flow control device and a flow control method for the flow control device. By setting up parallel branches, it switches to a standby unit to maintain continuous operation when wear or failure of the working valve is detected. This hardware redundancy mechanism is a passive switching based on the mechanical life of the actuator and does not involve the dynamic coupling relationship between the fluid medium and the actuator. Faced with the shift of the transfer function poles caused by the viscosity drift of the medium, this scheme cannot detect and invert the physical impedance characteristics inside the pipeline, resulting in a mismatch between the control gain and the actual physical constraints, inducing nonlinear oscillations or dynamic pressure shocks.

[0004] Therefore, the technical problem to be solved by this invention is how to actively detect the impedance characteristics of a fluid transport system and complete the self-alignment compensation of control parameters while maintaining flow output, so as to eliminate the adjustment oscillation caused by the drift of medium characteristics. Summary of the Invention

[0005] To address the problems mentioned in the background art, the technical solution of the present invention is as follows: A flow adaptive compensation control method for fluid transport objects, comprising the following steps:

[0006] Step S1: Obtain the rated flow setpoint of the flow regulation loop;

[0007] Step S2: A carrier excitation signal of a preset frequency is superimposed on the rated flow given value to generate a combined excitation signal and output to the flow regulation execution unit to excite a micro-perturbation wave signal carrying the dynamic physical characteristics of the fluid inside the fluid pipeline.

[0008] Step S3: Real-time acquisition of feedback flow signals inside the fluid pipeline; extraction of characteristic response components with the same frequency as the carrier excitation signal using a coherent demodulation algorithm.

[0009] Step S4: Calculate the amplitude ratio of the characteristic response component to the carrier excitation signal to determine the response transmission ratio. The response transmission ratio is used to characterize the physical effective bandwidth of the controlled pipeline under the current fluid viscosity constraint.

[0010] Step S5: Monitor the numerical fluctuation of the response transmittance in real time, reconstruct the adjustment gain of the flow adaptive control law, and when the response transmittance decays, increase the value of the adjustment gain according to the reciprocal of the square root of the response transmittance to compensate for the flow tracking deviation caused by the narrowing of the physical effective bandwidth.

[0011] Step S6: Correct the deviation of the rated flow rate setpoint using the reconstructed adjustment gain, generate a flow compensation command and output it to the flow regulation execution unit, and make the instantaneous flow rate of the pipeline approach the rated flow rate setpoint by forcibly adjusting the driving frequency of the flow regulation execution unit.

[0012] Preferably, in step S5, if the value of the response transmittance is continuously lower than the blockage threshold stored in the controller, the flow regulation mode is switched to the steady-state energy maintenance mode. The steady-state energy maintenance mode limits the instantaneous output power of the flow regulation execution unit by reducing the gain weight of the differential term in the control algorithm, so as to avoid the surge of the actuator induced by the surge of fluid viscosity in the controlled pipeline, and ensure that the operating frequency of the flow regulation execution unit is maintained within the preset safe frequency envelope of the pump body.

[0013] Preferably, in step S2, a carrier excitation signal is generated using a pseudo-random frequency sequence, and the feedback flow signal is simultaneously mixed and stripped using an orthogonal reference signal to filter out background noise generated by mechanical vibration inside the fluid pipeline.

[0014] Preferably, the method further includes the following steps: step S401, calculating the phase lag angle of the characteristic response component relative to the carrier excitation signal; step S402, extracting the second harmonic component from the feedback flow signal; step S403, identifying the gas-liquid phase distribution inside the fluid pipeline based on the mapping rule between the phase lag angle and the second harmonic component.

[0015] Preferably, through calculation items Monitor the wear condition of the flow regulation actuator, among which, item Satisfy the following mathematical relationship: ,in, Harmonic energy ratio, To provide the total energy value of the higher harmonic components in the feedback flow signal, This refers to the energy value of the fundamental component in the feedback flow signal.

[0016] Preferably, it also includes real-time monitoring of the slope of the change in the adjustment gain, and initiating time-domain consistency arbitration logic when the slope exceeds a preset rate of change threshold, in order to intercept transient distortion signals in the feedback flow signal.

[0017] Preferably, the carrier frequency of the carrier excitation signal is set to... Hz to Hz, and the carrier frequency is not lower than the cutoff frequency of the flow regulation loop. times.

[0018] Preferably, the method further includes calculating the thickness of the scale buildup on the inner wall of the fluid pipeline based on the cumulative attenuation rate of the response transmittance within a preset monitoring period.

[0019] Preferably, the outlet end of the fluid pipeline is equipped with a pressure buffer unit to absorb the dynamic pressure shock fluctuations inside the controlled pipeline when the flow compensation command changes abruptly.

[0020] Preferably, it also includes generating and sending a preventive maintenance warning signal to the monitoring terminal when the response transmittance is lower than a preset safety lower limit threshold.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] 1. In the adaptive compensation of flow rate of fluid transport objects, by continuously injecting high-frequency perturbation signals higher than the system sampling bandwidth into the basic control commands, the instantaneous dynamic impedance characteristics of the transport system are extracted in real time by utilizing the same frequency component in the flow feedback signal. The flow regulation process is transformed from a post-feedback mode based on error changes to a predictive compensation mode based on physical feature inversion. When the fluid viscosity changes with environmental fluctuations or pipeline obstruction, the proportional gain of the control loop is reconstructed before the flow deviation is formed by detecting the attenuation of the carrier response amplitude. This eliminates the nonlinear oscillation induced by the adjustment phase lag under high viscosity and large hysteresis conditions.

[0023] 2. An energy transmittance analysis mechanism between high-frequency perturbation signals and characteristic response components is established, enabling dynamic alignment between control energy output and the physical system's acceptance capability. The ratio of the injected signal power spectral density to the feedback signal power spectral density is used to characterize the physical system's adjustment bandwidth. When the energy transmittance drops below the critical threshold, the system automatically adjusts the adaptive compensation correction step size. Based on the controller's ability to sense the physical system's adjustment boundary, pump surge or pipeline hammering phenomena caused by blindly pursuing zero deviation when the fluid approaches a quasi-blockage state are avoided, ensuring the physical stability of the delivery process.

[0024] 3. A multi-dimensional signal analysis scheme based on carrier phase deviation and harmonic energy distribution is adopted to achieve synchronous monitoring of fluid phase state, actuator mechanical health status, and pipeline physical status. Utilizing the propagation hysteresis characteristics and nonlinear truncation distortion law of carrier signals in different media, the phase shift, second harmonic component, and higher harmonic energy distribution of characteristic response components are used as detection indicators. Through feature decoupling at the logic level, different physical causes such as fluid gas content, actuator clearance wear, or pipeline fouling are identified. This synergistic application of multiple mechanisms enables the system to distinguish the physical nature of flow deviation and switch compensation weights or output maintenance warnings accordingly, realizing the integration of functions such as flow regulation, status monitoring, and equipment diagnosis. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the logic flow of the adaptive flow compensation control method of the present invention;

[0026] Figure 2 This is a diagram showing the control architecture and module interaction of the flow adaptive compensation control system of the present invention. Detailed Implementation

[0027] The technical solution provided by the present invention will be described below with reference to the accompanying drawings and specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not intended to limit the scope of protection of the present invention.

[0028] This invention provides a flow adaptive compensation control method for fluid transportation, comprising an excitation signal injection module, a feedback feature extraction module, an impedance mapping calculation module, and a gain adaptive adjustment module. Addressing the technical problem of nonlinear drift caused by temperature fluctuations in the viscosity of the medium during fluid transportation, the method executes a flow regulation loop initialization program, the processor obtains the rated flow setpoint, and a carrier excitation signal of a preset frequency is superimposed on the rated flow setpoint. The combined excitation signal is generated and output to the flow regulation execution unit, and the carrier excitation signal is also included. The frequency is set at Hz to Within the Hz range, and not lower than the cutoff frequency of the flow regulation loop. Times, carrier excitation signal A micro-perturbation wave signal carrying the dynamic physical characteristics of the fluid is excited inside the fluid pipeline, with the target flow rate as the target value. Taking the conveying condition of L / min as an example, if the basic drive frequency of the flow regulation actuator is Hz, then the injected amplitude is the base driving frequency. carrier excitation signal This causes high-frequency perturbations in the synthesized drive signal; the processor uses a coherent demodulation algorithm to acquire the feedback flow signal inside the fluid pipeline, and then mixes the feedback flow signal with the carrier excitation signal. Mixing orthogonal reference signals of the same frequency strips away the background noise from mechanical vibrations inside the fluid pipeline, thereby extracting the characteristic response components. Then, the characteristic response components are calculated. With carrier excitation signal The power spectral density ratio is used to determine the response transmittance. Response transmittance Used to characterize the physical effective bandwidth of a controlled pipeline under current fluid viscosity constraints; specifically, response transmittance. Satisfy the formula ;in, In response to transmittance, Characteristic response components The effective power, carrier excitation signal The injection power.

[0029] The processor monitors the response transmittance in real time. The numerical fluctuations and the adjustment gain of the flow adaptive control law are reconstructed when the response transmittance When attenuation occurs, based on the response transmittance The reciprocal of the square root of the gain is used to increase the value of the adjustment gain to compensate for the flow tracking deviation caused by the narrowing of the physical effective bandwidth. The reconstructed adjustment gain Satisfy the formula ;in, The reconstructed adjustment gain, The preset base adjustment gain, The nominal response transmittance under standard operating conditions. The response transmittance is calculated in real time. The flow regulation mode switching blocking threshold is determined based on the damped step response experiment calibration. The controlled pipeline is filled with a viscosity gradient. to Test medium, record the response transmittance at different viscosities Steady-state values ​​and the output power fluctuation rate of the flow regulation actuator will be adjusted to achieve the desired output power fluctuation rate. Critical point corresponds to the response transmittance The storage serves as the discrimination boundary, and the gain is reconstructed and adjusted in the real-time computing logic. Satisfy the formula To correct the adjustment deviation caused by fluid viscosity drift, during the gain reconstruction process, the processor monitors the slope of the adjustment gain change. If the slope exceeds the preset rate of change threshold, the time-domain consistency arbitration logic is activated to intercept transient distortion signals in the feedback flow signal and maintain the stability of the adjustment gain.

[0030] To address the monitoring needs of actuator wear and pipeline fouling, the processor extracts the second harmonic component and higher harmonic energy distribution from the feedback flow signal, and calculates the harmonic energy ratio. Monitor the wear condition of the flow regulation actuator; this ratio Satisfy the formula ;in, Harmonic energy ratio, To provide the total energy value of the higher harmonic components in the feedback flow signal, To extract the energy value of the fundamental component in the feedback flow signal, the higher harmonic components of the feedback flow signal are extracted using the carrier frequency. sampling frequency of more than times, using Sampling frequency acquisition includes The discrete sequence of the subharmonic components is truncated using a sliding time window. A sequence of sampled periods is used to perform power spectral analysis based on discrete Fourier transform to calculate the harmonic energy ratio. synchronously using cutoff frequency Low-pass filter response transmittance Smoothing processing filters out non-physical numerical jumps caused by sensor measurement noise; the sampling period is set to... Monitoring the nonlinear amplitude cutoff characteristics caused by mechanical wear of the flow regulation actuator, switching to steady-state energy maintenance mode, if the response transmittance If the value remains below the blocking threshold, the flow regulation mode is switched to steady-state energy maintenance mode. By reducing the gain weight of the differential term in the control algorithm, the instantaneous output power of the flow regulation execution unit is limited, keeping the operating frequency of the flow regulation execution unit within the preset safe frequency envelope of the pump body. To address the issue of secondary oscillation of the actuator induced by sudden jumps in control parameters during the switch between adaptive compensation mode and steady-state energy maintenance mode, a control vector perturbation-free tracking program is executed. This is achieved by monitoring the response transmittance. When the value falls to the blocking threshold, the current output value of the adaptive adjustment loop is latched as the integral initial value of the steady-state maintenance loop, and the gain is adjusted using a first-order inertial filter. Evolution slope control is implemented to limit the rate of change of the flow regulation execution unit drive frequency to within the preset safe frequency envelope, thereby eliminating the dynamic pressure shock caused by sudden changes in pipeline physical resistance through smooth coupling at the logic level.

[0031] The processor synchronously calculates the carrier excitation signal. With characteristic response components Phase lag angle between Based on phase lag angle The processor identifies the gas-liquid phase distribution inside the fluid pipeline based on the mapping rules with the second harmonic component. This gas-liquid phase distribution identification employs a multi-dimensional feature vector lookup table method. During the system debugging phase, a volumetric gas content is injected into the pipeline. to Mixed media, obtain the corresponding phase hysteresis angle The distribution sequence of the second harmonic energy proportion of the feedback flow signal is stored as a discretized phase characteristic fingerprint database, and the processor calculates the characteristic response components during real-time monitoring. Generate phase lag angle Extract the second harmonic amplitude of the feedback flow signal, when the phase lag angle Compared to the pure liquid operating condition, the reference phase offset exceeds Furthermore, the second harmonic amplitude accounts for more than [a certain percentage] of the fundamental amplitude. The processor determines that air bubble interference exists inside the fluid pipeline and invokes an impedance mapping rule optimized for compressible media, reducing the adjustment gain. The proportional branch weights offset the flow response lag induced by the gas compression and storage effect, when the phase lag angle... When the phase value increases and exceeds the preset phase threshold, it is determined that the compressibility of the fluid transport medium has increased. The processor reduces the correction strength of the adjustment gain to the rated flow setpoint, corrects the rated flow setpoint using the reconstructed adjustment gain, generates a flow compensation command and outputs it to the flow regulation execution unit. By adjusting the drive frequency of the flow regulation execution unit, the instantaneous flow rate of the pipeline is made to approach the rated flow setpoint. In addition, a pressure buffer unit is provided at the outlet end of the fluid pipeline. The pressure buffer unit is used to absorb the dynamic pressure shock fluctuation inside the controlled pipeline when the flow compensation command changes.

[0032] Example 1: In the reactor feeding operation of a fine chemical production line, the controlled fluid medium is a polymer solution with thermosensitive viscosity characteristics, and the rated flow rate is set to [value missing]. L / min, ambient temperature from Reduce to The decrease in temperature leads to an increase in the dynamic viscosity of the fluid, causing a nonlinear transition in the flow resistance characteristics within the fluid pipeline. If a proportional-integral-derivative (PID) control method based on flow error feedback is used, the shift of the transfer function poles caused by the increased medium viscosity will result in phase lag in the flow regulation actuator. When the flow regulation loop attempts to eliminate the steady-state deviation by increasing the proportional gain, a frequency of [frequency value missing] is generated within the controlled pipeline. Low-frequency dynamic pressure oscillations of Hz, this phenomenon causes the conveying flow rate to be... L / min to Significant fluctuations within the L / min range, and due to the mismatch between the adjustment command and the pipeline's physical response window, induce surge and impact noise in the pump body; the flow adaptive compensation control system performs parameter self-alignment compensation under this operating condition, and the excitation signal injection module... Based on the rated flow rate given in L / min, the superimposed frequency is... Hz and amplitude is the driving frequency carrier excitation signal The system generates high-frequency micro-perturbation wave signals carrying the dynamic physical characteristics of the fluid inside the fluid pipeline. The feedback feature extraction module extracts the characteristic response components from the feedback flow signal through a coherent demodulation algorithm. The impedance mapping calculation module calculates the characteristic response components in real time. Relative to carrier excitation signal The power spectral density ratio was used to monitor the response transmittance. From the initial calibration value Reduce to This value characterizes the physical inhibition effect of increased fluid viscosity on regulating energy.

[0033] Based on this, the gain adaptive adjustment module adjusts according to the response transmittance. Real-time changes, execute the adjustment gain reconstruction logic, and adjust the base adjustment gain. The adjustment gain is automatically corrected to the reconstructed value based on preset rules. Among them, the reconstructed adjustment gain Satisfy the formula ,in, The reconstructed adjustment gain, The preset base adjustment gain, The nominal response transmittance under standard operating conditions. The response transmittance is calculated in real time. Under the cooperation of the injected high-frequency perturbation signal and the gain reconstruction control law, the system transforms viscosity changes into an impedance matching state based on the physical effective bandwidth. This is achieved by increasing the adjustment gain. Improve the driving performance of the flow regulation actuator under high viscosity conditions, so that the actual flow output can be stabilized again. L / min and steady-state error controlled within Within the range, low-frequency oscillations induced by phase lag are eliminated. By introducing a physical probe carrier that exceeds the closed-loop bandwidth into the control loop, the system can sense the changing trend of pipeline physical constraints and complete the correction of control parameters before the flow deviation is formed. This architecture, which establishes a mapping relationship between control logic and physical impedance response, enables the fluid transport system to maintain constant dynamic regulation performance in variable temperature environments.

[0034] Example 2: Equipped with a frequency converter drive unit, the measurement range is L / min to L / min and measurement accuracy is On a physical experimental platform for electromagnetic flowmeters and real-time controllers, to address the problem of system regulation quality degradation caused by viscosity and thermosensitive drift of the controlled fluid medium, the system sampling period was set to [value missing]. The selection of this parameter, ms, balances the accuracy of capturing high-frequency perturbation signals with the processing load of the control unit; that is, it ensures that the coherent demodulation algorithm can reconstruct the frequency as... Hz carrier excitation signal The sampling frequency needs to be set to the carrier frequency. To provide sufficient phase information sampling points, the experiment superimposed a signal-to-noise ratio of more than 10 times in the flow feedback loop. dB Gaussian white noise was used to simulate electromagnetic interference in an industrial setting, and samples were prepared with mass fractions of... , and Polyacrylamide solutions respectively corresponding to mPa·s, mPa·s and The dynamic viscosity gradient in mPa·s was used, and a traditional proportional-integral-derivative controller without physical impedance sensing was set up as a control group to verify the effect of responding to transmittance. The compensation effect of reconstructing the adjustment gain; during the experimental operation phase, the excitation signal injection module in The amplitude superimposed on the basic flow rate setpoint of L / min is the driving frequency. carrier excitation signal The processor extracts the characteristic response components from the feedback flow signal in real time. And calculate the response transmittance. For specific gradient verification data, please refer to Table 1.

[0035] Table 1: Example Table of Gradient Validation Data

[0036]

[0037] Analyzing the data evolution patterns recorded in Table 1, in the test sequence of the sample group of this invention, as the fluid viscosity increased from... mPa·s increased to mPa·s, the response transmittance detected by the system in real time The occurrence of regular attenuation indicates that the physical acceptance bandwidth of the fluid medium for regulating energy is narrowing, and the reconstructed regulating gain stabilizes the final flow fluctuation rate. The following range, when the carrier frequency is set to In the out-of-range control group of Hz, the response transmittance is lower because the excitation frequency exceeds the physical cutoff frequency of the pipeline. decay to This causes the gain reconstruction logic to fail, increasing its flow volatility to [a certain value]. When the viscosity rises to mPa·s results in a response transmittance After the blocking threshold is triggered, the system automatically switches to steady-state energy maintenance mode and limits the instantaneous jump in drive power, thus mitigating pump oscillations induced by forcibly increasing gain under high damping conditions.

[0038] Example 3: This example combines Figures 1 to 2 This paper describes an adaptive compensation control method for flow rate of fluid transport objects, such as... Figure 1As shown, starting from step S1, the rated flow setpoint of the flow regulation loop is obtained. In step S2, a carrier excitation signal of a preset frequency is superimposed on the rated flow setpoint to generate a combined excitation signal, which is then output to the flow regulation execution unit to excite a micro-perturbation wave signal carrying the dynamic physical characteristics of the fluid inside the fluid pipeline. Simultaneously, step S3 is executed to collect the feedback flow signal inside the fluid pipeline in real time. The characteristic response component with the same frequency as the carrier excitation signal is extracted by a coherent demodulation algorithm. Then, step S4 is executed to calculate the amplitude ratio of the characteristic response component relative to the carrier excitation signal to determine the response transmission ratio, which is used to characterize the physical effective bandwidth of the controlled pipeline under the current fluid viscosity constraint. Based on this, step S5 is executed to monitor the numerical fluctuation of the response transmission ratio in real time and reconstruct the adjustment gain of the flow adaptive control law. When the response transmission ratio decays, the adjustment gain is increased according to the reciprocal of its square root to compensate for the flow tracking deviation caused by the narrowing of the physical effective bandwidth. Finally, step S6 is executed to use the reconstructed adjustment gain to correct the deviation of the rated flow setpoint, generate a flow compensation command, and output it to the flow regulation execution unit. By adjusting the driving frequency, the instantaneous flow of the pipeline is made to approach the rated flow setpoint.

[0039] like Figure 2 As shown, the system uses an embedded controller as its core control layer. Internally, it integrates in parallel an excitation signal injection module for generating carrier waves and combined excitations, a feedback feature extraction module for performing coherent demodulation and same-frequency extraction, an impedance mapping calculation module for calculating the response transmission ratio, and a gain adaptive adjustment module for reconstructing gain and generating compensation commands. The excitation signal injection module generates a flow compensation command containing combined excitations, which is sent to a flow regulation execution unit containing a pump and drive mechanism. This drives the fluid delivery pipeline, which is the controlled object. A flow acquisition sensor, acting as a feedback signal source, collects the flow feedback signal containing the same-frequency response in real time and sends it back to the feedback feature extraction module. Simultaneously, the fluid delivery pipeline is connected to a pressure buffer unit for absorbing dynamic pressure shocks. Furthermore, the core control layer connects to a remote monitoring terminal via a communication link, sending maintenance warnings and status data. The remote monitoring terminal receives maintenance warnings and displays status information.

[0040] Example 4: In a non-Newtonian fluid mixing condition involving intermittent gas injection, the irregular fluctuations in the internal gas phase ratio of the controlled fluid medium cause high-frequency oscillations in the physical effective bandwidth within the controlled pipeline. After receiving the rated flow rate setpoint, the flow regulation execution unit extracts the high-frequency perturbation signal through the processor, including the following ordered operation steps: using a sampling frequency of... The Hz analog-to-digital converter acquires the feedback flow signal sequence. The processor synchronously inputs the sequence into two parallel multiplication operators; the processor then processes the sequence... Each with a frequency of Hz and phase difference Orthogonal reference signal of degree and Multiplication achieves frequency shifting of the signal from the passband to the baseband; passing through a cutoff frequency of A second-order Butterworth low-pass filter at Hz filters out the sum-frequency component generated by mixing, obtaining the in-phase component. Orthogonal components Fourth step, calculate the characteristic response components. effective power Specifically, effective power Satisfy the formula ;in, Characteristic response components The effective power, For in-phase components, For orthogonal components, For sampling index value, carrier excitation signal frequency, For the sampling period, the system completes the distortion-free extraction of the instantaneous response characteristics of the controlled pipeline through the digital signal processing path determined above.

[0041] To address the response deviation issue caused by changes in the compressibility of the medium under gas-liquid two-phase flow conditions, the processor is based on characteristic response components. Relative to carrier excitation signal phase lag angle The logic for identifying the physical phase state is anchored to the functional relationship between the fluid's bulk elastic modulus and wave propagation delay. The processor pre-stores nominal delay curves for different gas-liquid ratios, and detects the phase lag angle. Compared to the reference phase offset under pure liquid conditions, the difference exceeds When the gas volume content inside the pipeline exceeds a certain level, it is determined that the gas volume content exceeds a certain level. At the critical point, the processor automatically retrieves the impedance mapping rule optimized for compressible media and reduces the adjustment gain. The proportional coefficient component is used to offset the control energy retention induced by the gas compression storage effect. This transforms the difficult-to-quantify phase disturbance into a predictable change in the controlled pipeline physical parameters, allowing the system to maintain the flow deviation within a certain range during the transient process of bubble entry. Within the variable envelope of L / min; to eliminate spurious triggering of the gain adaptive adjustment process by electromagnetic interference, the system executes a dynamic calibration program targeting the rate of change threshold, using a sliding window to acquire continuous data. Response transmittance per cycle And calculate its sample variance, and then... The standard deviation is defined as the adaptive rate of change threshold under the current environmental noise. The adjustment gain obtained in real-time is... If the first-order difference value is outside the threshold range of the rate of change, the arbitration logic determines that the jump is a non-physical viscosity drift and drives the flow regulation execution unit to enter the zero-gain correction mode, that is, latch the effective regulation parameters of the previous moment until the feedback characteristics return to the steady-state probability range defined by the sample variance. This real-time calibration method based on the statistical characteristics of measurement data provides a judgment criterion for the time-related consistency arbitration logic, ensuring that the issuance of the flow compensation command only responds to the actual impedance evolution of the fluid transport object.

[0042] Example 5: In the initial commissioning scenario of a newly installed industrial fluid transport pipeline system, to ensure that the flow adaptive compensation control system has a consistent sensing reference for pipelines with different physical properties, the system performs a standard physical impedance characteristic calibration procedure before being put into production operation, and fills the controlled pipeline with a constant viscosity. A standard test medium of mPa·s was injected with a carrier excitation signal when the flow regulation actuator was at its rated operating frequency. The processor acquires the same-frequency components in the flow feedback loop in parallel and calculates the instantaneous power spectral density, utilizing the acquired characteristic response components. With carrier excitation signal The power ratio determines the nominal response transmittance. The calibration results satisfy the formula ;in, The nominal response transmittance, The effective power of the characteristic response components under standard medium. The processor injects power into the carrier excitation signal under standard conditions and stores this value as a physical reference for subsequent gain reconstruction logic to offset the inherent energy attenuation characteristics caused by pipeline geometry and sensor arrangement.

[0043] When the system faces deployment conditions such as sensor replacement or a change in the type of fluid being transported, the processor initiates an adaptive rate-of-change threshold field calibration procedure to eliminate the impact of installation stress and environmental noise drift on control performance. The system enters a zero-load cyclic mode and continuously monitors the distribution of high-order harmonic components in the feedback flow signal. The processor then continuously... Harmonic energy ratio is obtained through a sliding filter within each sampling period. The statistical mean, and according to the formula Determine the monitoring threshold for the flow regulation execution unit; whereby, For monitoring thresholds, The average energy ratio under the noise floor. The standard deviation of the background fluctuation is used, and the response transmittance is obtained by adjusting the opening of the reflux valve. The measured value at the blocking critical point is set as the locking trigger boundary in the software logic. The program associates the monitoring indicators with the physical hardware status and completes the alignment of the control law parameters with the boundary conditions of the operating environment.

[0044] Example 6: In a spectrum adaptation scenario for a controlled fluid pipeline system, the system executes a frequency parameter determination procedure based on energy transmission gradient scanning. The flow regulation execution unit receives the frequency from... Hz Hz increments continuously to The Hz sweep instruction allows the processor to acquire the instantaneous flow response sequence at the end of the fluid pipeline and calculate the characteristic response components. The effective power value is determined by calculating the attenuation slope of the power spectral density in the frequency domain to identify the phase cutoff frequency of the controlled pipeline. The frequency point where the power drops to half of the injected power is determined as the physical effective bandwidth boundary. According to the physical effective bandwidth boundary of Double the carrier excitation signal center operating frequency The processor will calibrate the generated frequency parameters. The parameter list stored in the excitation signal injection module establishes a spectral matching relationship between the detection signal frequency and the pipeline physical environment.

[0045] When the system faces the risk of dynamic pressure surge induced by a change in flow compensation command, the processor initiates the sensitivity weight calibration procedure of the impedance mapping model. The system injects a constant amplitude step pulse signal into the flow regulation loop and records different response transmittance ratios. The adjustment time for the feedback flow signal to reach a steady-state value under the given condition is used to adjust the response transmittance. Calculate the compensation factor using partial derivatives The correction strength of the flow adaptive control law is reconstructed based on the compensation factor, and the calibrated adjustment gain satisfies the mathematical relationship. ;in, The reconstructed adjustment gain, The preset base adjustment gain, The nominal response transmittance, The response transmittance is calculated in real time. As a compensation factor calibrated by a step signal, the program maps the physical response delay to the proportional weight coefficient of the control law, eliminating the flow compensation gain error caused by the difference in rheological properties of the conveying medium, and maintaining the dynamic stability of the conveying process under the environment of fluctuating physical properties.

[0046] In industrial fluid transport pipelines equipped with pneumatic energy dissipators, the processor executes an adaptive calibration program for the pre-charge pressure of the pressure buffer unit. This involves acquiring the pressure response curve at the outlet when the pipeline flow rate undergoes a step compensation and extracting its logarithmic attenuation reduction. A relationship between the logarithmic attenuation reduction and the response transmittance is then established. A mapping model is used to adjust the damping of the pressure buffer unit in real time, ensuring that the peak value of the dynamic pressure impact inside the pipeline is always lower than the pipeline's pressure-bearing capacity. The program ensures the physical reliability of the flow adaptive compensation process under variable viscosity conditions by dynamically matching the physical energy dissipation characteristics with the control gain reconstruction logic.

[0047] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A flow rate adaptive compensation control method for fluid transport objects, characterized in that, Includes the following steps: Step S1: Obtain the rated flow setpoint of the flow regulation loop; Step S2: A carrier excitation signal of a preset frequency is superimposed on the rated flow given value to generate a combined excitation signal and output to the flow regulation execution unit to excite a micro-perturbation wave signal carrying the dynamic physical characteristics of the fluid inside the fluid pipeline. Step S3: Real-time acquisition of feedback flow signals inside the fluid pipeline; extraction of characteristic response components with the same frequency as the carrier excitation signal using a coherent demodulation algorithm. Step S4: Calculate the amplitude ratio of the characteristic response component relative to the carrier excitation signal to determine the response transmission ratio. The response transmission ratio is used to characterize the physical effective bandwidth of the controlled pipeline under the current fluid viscosity constraint. Step S5: Monitor the numerical fluctuation of the response transmittance in real time, reconstruct the adjustment gain of the flow adaptive control law, and when the response transmittance decays, increase the value of the adjustment gain according to the reciprocal of the square root of the response transmittance to compensate for the flow tracking deviation caused by the narrowing of the physical effective bandwidth. Step S6: Correct the deviation of the rated flow setpoint using the reconstructed adjustment gain, generate a flow compensation command and output it to the flow regulation execution unit, and make the instantaneous flow of the pipeline approach the rated flow setpoint by forcibly adjusting the driving frequency of the flow regulation execution unit. And, in step S401, calculate the phase lag angle of the characteristic response component relative to the carrier excitation signal; Step S402: Extract the second harmonic component from the feedback flow signal; Step S403: Based on the mapping rule between the phase lag angle and the second harmonic component, identify the gas-liquid phase distribution inside the fluid pipeline.

2. The flow rate adaptive compensation control method for fluid transport objects according to claim 1, characterized in that, In step S5, if the response transmittance value continues to be lower than the blocking threshold stored in the controller, the flow regulation mode is switched to steady-state energy maintenance mode. The steady-state energy maintenance mode limits the instantaneous output power of the flow regulation execution unit by reducing the gain weight of the differential term in the control algorithm.

3. The flow adaptive compensation control method for fluid transport objects according to claim 1, characterized in that, In step S2, a carrier excitation signal is generated using a pseudo-random frequency sequence, and the feedback flow signal is simultaneously mixed and stripped using an orthogonal reference signal.

4. The flow rate adaptive compensation control method for fluid transport objects according to claim 1, characterized in that, Through calculation items Monitor the wear condition of the flow regulation actuator, among which, item Satisfy the following mathematical relationship: ,in, Harmonic energy ratio, To provide the total energy value of the higher harmonic components in the feedback flow signal, This refers to the energy value of the fundamental component in the feedback flow signal.

5. The flow adaptive compensation control method for fluid transport objects according to claim 1, characterized in that, It also includes real-time monitoring of the slope of the gain change and initiating time-domain consistency arbitration logic when the slope exceeds a preset rate of change threshold to intercept transient distortion signals in the feedback flow signal.

6. The flow adaptive compensation control method for fluid transport objects according to claim 1, characterized in that, The carrier frequency of the carrier excitation signal is set to... Hz to Hz, and the carrier frequency is not lower than the cutoff frequency of the flow regulation loop. times.

7. The flow adaptive compensation control method for fluid transport objects according to claim 1, characterized in that, It also includes calculating the thickness of scale buildup on the inner wall of the fluid pipeline based on the cumulative attenuation rate of the response transmittance within a preset monitoring period.

8. The flow adaptive compensation control method for fluid transport objects according to claim 1, characterized in that, A pressure buffer unit is provided at the outlet end of the fluid pipeline to absorb the dynamic pressure shock fluctuations inside the controlled pipeline when the flow compensation command changes abruptly.

9. The flow adaptive compensation control method for fluid transport objects according to claim 1, characterized in that, It also includes generating and sending a preventative maintenance warning signal to the monitoring terminal when the response transmittance is lower than a preset safety lower limit threshold.

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