A sewage treatment process data real-time inspection method and system

Abstract

The application relates to the technical field of data processing, in particular to a sewage treatment process data real-time inspection method and system. The method comprises the following steps: performing frequency signal and pressure signal smoothing alignment processing on a Roots blower on a sewage treatment production line to obtain a smoothed frequency sequence and a smoothed pressure sequence; when the change rate of the smoothed frequency sequence exceeds a preset threshold, it is determined that the Roots blower enters an active speed regulation period, and a characteristic area is determined based on the smoothed frequency sequence and the smoothed pressure sequence; the regression slope of the smoothed frequency sequence and the smoothed pressure sequence in the active speed regulation period is calculated, and an impedance offset factor of the regression slope relative to a reference slope is determined; and the inspection result of the Roots blower is output by using the characteristic area and the impedance offset factor. Through the above technical scheme, the Roots blower on the sewage treatment production line can be inspected.

Description

Technical Field

[0001] This application relates to the field of data processing technology, and in particular to a method and system for real-time inspection of wastewater treatment process data. Background Technology

[0002] A Roots blower is a gas conveying machine that operates based on the principle of volumetric rotation. In wastewater treatment processes, the Roots blower is the core power equipment of the aeration system, providing sufficient oxygen for the aerobic biological treatment stage. In the aerobic tank, microorganisms decompose organic pollutants in the wastewater through metabolism. The Roots blower pressurizes the air and releases it evenly into the water as bubbles through the aerator, increasing the contact area and contact time between the air and the wastewater, thereby increasing the dissolved oxygen concentration in the water and meeting the survival and metabolic needs of aerobic microorganisms. Roots blowers can also be used in processes such as aerobic sludge digestion or sludge transport.

[0003] If a Roots blower malfunctions during operation, it will directly disrupt the process balance of the wastewater treatment system, leading to a significant decrease in treatment efficiency. If the Roots blower malfunctions, it will cause insufficient airflow or reduced air pressure, making it impossible for the dissolved oxygen concentration in the aerobic tank to meet the process requirements. When the dissolved oxygen concentration is too low, the activity of aerobic microorganisms is inhibited, and the decomposition efficiency of organic pollutants is greatly reduced. The hypoxic environment will promote the growth of anaerobic microorganisms in the tank, causing problems such as sludge bulking or foul odor in the water, further deteriorating the quality of the effluent.

[0004] If faults in the Roots blower are not detected in time, the blower will operate in an inefficient and energy-intensive state for a long time, and may even cause serious accidents such as belt breakage or motor burnout, resulting in unplanned shutdown of the production line and affecting the efficiency of the sewage treatment process. Therefore, it is necessary to conduct inspections of the Roots blowers on the sewage treatment production line. Summary of the Invention

[0005] To conduct inspections of Roots blowers on wastewater treatment production lines, this application provides a method and system for real-time inspection of wastewater treatment process data.

[0006] According to a first aspect of the embodiments of this application, a method for real-time inspection of wastewater treatment process data is provided, comprising: performing smoothing and alignment processing on the frequency signal and pressure signal of a Roots blower on a wastewater treatment production line to obtain a smoothed frequency sequence and a smoothed pressure sequence; determining that the Roots blower has entered an active speed regulation cycle when the rate of change of the smoothed frequency sequence exceeds a preset threshold, and constructing a two-dimensional phase plane based on the smoothed frequency sequence and the smoothed pressure sequence to calculate the characteristic area enclosed by the running trajectory in the active speed regulation cycle on the two-dimensional phase plane; calculating the regression slope of the smoothed frequency sequence and the smoothed pressure sequence in the active speed regulation cycle, and determining the impedance offset factor of the regression slope relative to the reference slope; inputting the characteristic area and the impedance offset factor into a multidimensional nonlinear fusion model, and calculating the transmission anomaly index of the Roots blower by nonlinearly activating the characteristic area and combining it with the linear superposition of the impedance offset factor, so as to output the inspection result of the Roots blower according to the transmission anomaly index.

[0007] In this way, by capturing the dynamic response characteristics of the Roots blower during the active speed regulation cycle, the mechanical hysteresis characteristics of the transmission system are characterized by the characteristic area in the two-dimensional phase plane, and the flow resistance characteristics of the gas path system are characterized by the impedance offset factor of the regression slope. By inputting the two into a multi-dimensional nonlinear fusion model, the decoupling and quantification of different types of fault mechanisms are achieved. It is possible to identify the transmission abnormalities and gas path abnormalities of the Roots blower using existing frequency data and pipeline pressure data, thereby improving the real-time performance and accuracy of the inspection.

[0008] Optionally, the active speed regulation cycle includes one complete acceleration process and one complete deceleration process; calculating the characteristic area enclosed by the running trajectory in the two-dimensional phase plane within the active speed regulation cycle includes: for each complete acceleration and deceleration process within the active speed regulation cycle, traversing all sampling points, calculating the first product of the smoothing frequency of the current sampling point and the smoothing pressure of the next sampling point, and the second product of the smoothing frequency of the next sampling point and the smoothing pressure of the current sampling point; calculating the difference between the first product and the second product, and accumulating the differences corresponding to all adjacent sampling points within the entire active speed regulation cycle, and determining the characteristic area based on the absolute value of the accumulation result.

[0009] In this way, by using the area of ​​the hysteresis loop formed by frequency and pressure on the phase plane as the characteristic area, which corresponds to the loss and delay in the energy transmission process of the transmission system, the belt slack can be sensitively reflected, so as to realize the inspection of the Roots blower on the sewage treatment production line.

[0010] Optionally, the regression slopes of the smoothed frequency sequence and the smoothed pressure sequence within the active speed regulation period are calculated, including: determining the pressure arithmetic mean of the smoothed pressure sequence and the frequency arithmetic mean of the smoothed frequency sequence within the active speed regulation period; calculating the pressure deviation between the smoothed pressure and the pressure arithmetic mean at each sampling point, and the frequency deviation between the smoothed frequency and the frequency arithmetic mean at each sampling point; using the sum of the products of the pressure deviations and frequency deviations at all sampling points as the covariance term, the sum of the squares of the frequency deviations at all sampling points as the variance term, and the ratio of the covariance term to the variance term as the regression slope.

[0011] Optionally, the transmission anomaly index of the Roots blower is determined by the following formula: ,in, This refers to the transmission anomaly index of the Roots blower. It is a natural constant. The preset gain coefficient, For the characteristic area, The preset area threshold, The preset weighting coefficients, This is the impedance offset factor. This is the standard impedance constant used for normalization.

[0012] Optionally, the inspection results of the Roots blower are output based on the transmission abnormality index, including: comparing the transmission abnormality index of the Roots blower with a preset alarm threshold to determine whether there is an abnormality in the transmission of the Roots blower; if it is determined that there is an abnormality in the transmission of the Roots blower, the fault type of the Roots blower is determined based on the contribution weight of the characteristic area and impedance offset factor to the transmission abnormality index of the Roots blower.

[0013] This enables fault attribution and reduces the time cost for maintenance personnel to troubleshoot.

[0014] Optionally, the transmission abnormality index of the Roots blower is determined based on the nonlinear activation term of the characteristic area and the linear superposition term of the impedance offset factor. If an abnormality is found in the transmission of the Roots blower, the fault type is determined as follows: if the ratio of the nonlinear activation term to the linear superposition term is greater than or equal to a predetermined ratio, the fault type is determined to be abnormally loose transmission belt; if the ratio is less than a predetermined ratio, the fault type is determined to be air intake system blockage.

[0015] In this way, by identifying the type of failure in the Roots blower, on-site personnel can easily take targeted maintenance measures.

[0016] Optionally, the rate of change of the smoothed frequency sequence is determined by calculating the smoothed frequency difference within adjacent time windows; the smoothed pressure sequence is determined as follows: pressure data is obtained by performing a weighted moving average calculation on the discrete pressure signal of the Roots blower using time decay weights; the time decay weights are positively correlated with the time difference between the current time; the pressure data calculated by the weighted moving average is corrected using the linear correction coefficient of the pressure sensor and the benchmark compensation value based on the current atmospheric pressure environment to generate a smoothed pressure sequence.

[0017] In this way, by introducing time decay weights, more recent data are given higher weights, which solves the data lag problem caused by the traditional averaging method. At the same time, by combining linear correction and benchmark compensation, the influence of sensor drift and ambient atmospheric pressure fluctuations on the absolute pressure value is eliminated.

[0018] Optionally, the method further includes: in response to the Roots blower receiving a shutdown command and the operating frequency returning to zero, acquiring the feedback value of the pressure sensor within a preset delay period; calculating the deviation value between the feedback value and the standard atmospheric pressure; if the deviation value is within a preset allowable range, updating the reference compensation value according to the deviation value, and using the updated reference compensation value to participate in the calculation of the smooth pressure sequence at subsequent times.

[0019] This allows for automatic zero-point calibration during the quiet window after the Roots blower is shut down.

[0020] Optionally, the method further includes: if the deviation value exceeds a preset allowable range, outputting a sensor fault alarm signal and stopping the updating of the reference compensation value.

[0021] According to a second aspect of the present application, a real-time inspection system for wastewater treatment process data is provided, comprising: a processor and a memory, wherein the memory stores computer program instructions, and the computer program instructions, when executed by the processor, implement the steps of the real-time inspection method for wastewater treatment process data provided in the first aspect of the present application.

[0022] The technical solutions provided by the embodiments of this application may include the following beneficial effects: For the Roots blower on the sewage treatment production line, frequency signals and pressure signals are smoothed and aligned to obtain smoothed frequency sequences and smoothed pressure sequences; when the rate of change of the smoothed frequency sequence exceeds a preset threshold, it is determined that the Roots blower has entered an active speed regulation cycle; a two-dimensional phase plane can be constructed based on the smoothed frequency sequence and smoothed pressure sequence to calculate the characteristic area enclosed by the running trajectory in the active speed regulation cycle on the two-dimensional phase plane; the regression slope of the smoothed frequency sequence and smoothed pressure sequence in the active speed regulation cycle is calculated, and the impedance offset factor of the regression slope relative to the reference slope is determined. The determination of the characteristic area takes into account the correlation between the smoothed frequency and smoothed pressure during the operation of the Roots blower. Using the characteristic area and the impedance offset factor, more accurate inspection results of the Roots blower can be output.

[0023] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0024] Figure 1 This is a flowchart illustrating a real-time inspection method for wastewater treatment process data according to an exemplary embodiment;

[0025] Figure 2 This is a schematic diagram of the feature area under different conditions in the embodiments of this application;

[0026] Figure 3 This is a comparative diagram of the test results of this application and the pressure alarm test results;

[0027] Figure 4 This is a schematic diagram illustrating the structure of a real-time inspection system for wastewater treatment process data according to an exemplary embodiment. Detailed Implementation

[0028] First, a brief introduction to the application scenario of the embodiments of this application will be given. In the application scenario of this application, the Roots blower in the sewage treatment system drives the impeller to rotate through belt drive and delivers high-pressure air to the bottom of the aeration tank. The Roots blower may malfunction, which will affect the sewage treatment effect of the sewage treatment system. Therefore, it is necessary to inspect the Roots blower on the sewage treatment production line.

[0029] To address the aforementioned technical problems, embodiments of this application provide a method and system for real-time inspection of wastewater treatment process data. Figure 1 This is a flowchart illustrating a real-time inspection method for wastewater treatment process data according to an exemplary embodiment, such as... Figure 1 As shown, the method includes the following steps.

[0030] In step S101, the frequency signal and pressure signal of the Roots blower on the sewage treatment production line are smoothed and aligned to obtain a smoothed frequency sequence and a smoothed pressure sequence.

[0031] In one embodiment, the rate of change of the smoothed frequency sequence is determined by calculating the smoothed frequency difference within adjacent time windows; the smoothed pressure sequence is determined by: using time decay weights to perform a weighted moving average calculation on the discrete pressure signal of the Roots blower to obtain pressure data; the time decay weights are positively correlated with the time difference between the current time; using the linear correction coefficient of the pressure sensor and the benchmark compensation value based on the current atmospheric pressure environment, the pressure data calculated by the weighted moving average is corrected to generate a smoothed pressure sequence.

[0032] For data acquisition of Roots blowers, data is usually obtained from the control system via an industrial fieldbus. The frequency signal can come from the real-time feedback of the frequency converter, and the sampling frequency can usually be set from 1Hz to 10Hz. The pressure signal can come from the pressure transmitter installed on the blower's outlet main pipe.

[0033] In real industrial environments, raw signals are often accompanied by electromagnetic interference and fluid pulsation noise. In order to obtain a high-quality data foundation, the raw signals can be smoothed.

[0034] The time decay weighting used can specifically employ an exponentially weighted moving average algorithm. For example, let the current time be... Historical moment Then at time weight It can be represented as ,in The smoothing factor can be, for example, 0.2. The time decay weight is positively correlated with the time difference between the current time and the previous time.

[0035] In wastewater treatment plants, aeration pipes can be hundreds of meters long. Pressure wave reflections occur within the pipes, which may cause high-frequency fluctuations in pressure sensor readings. Directly using the raw data to calculate subsequent derivatives or integrals may amplify the noise and lead to misjudgments.

[0036] The weighted moving average with time decay weights can respond more quickly to pressure changes caused by variations in the speed of the Roots blower compared to a simple arithmetic average, avoiding the phase lag caused by the traditional averaging method. By introducing a linear correction coefficient and a reference compensation value for the pressure sensor, the systematic errors caused by sensor manufacturing tolerances and the zero-point drift caused by changes in ambient atmospheric pressure can be eliminated.

[0037] In one embodiment, in response to the Roots blower receiving a shutdown command and the operating frequency returning to zero, the feedback value of the pressure sensor can be collected within a preset delay period; the deviation between the feedback value and the standard atmospheric pressure can be calculated; if the deviation is within a preset allowable range, the reference compensation value can be updated according to the deviation value, and the updated reference compensation value can be used to participate in the calculation of the smooth pressure sequence at subsequent times.

[0038] The operation mode of Roots blowers is usually intermittent or rotating. When the control system of the sewage treatment production line issues a shutdown command to the Roots blower, the frequency converter output frequency drops to 0; the impeller of the Roots blower stops rotating, and the pressure in the outlet pipe should gradually drop back to the ambient atmospheric pressure; the preset delay period can be set to a range of 30 to 60 seconds after shutdown to avoid water hammer effect fluctuations at the moment of shutdown.

[0039] The pressure sensor feedback value can be collected within a preset delay period. and standard atmospheric pressure For comparison, the standard atmospheric pressure can be, for example, 101.3 kPa or determined based on altitude, and the deviation is calculated. ;like If the drift is less than a preset threshold, the sensor drift is determined to be within the calibrable range, and the reference compensation value is updated. .

[0040] The pressure-sensitive element inside the pressure sensor may age, causing zero-point drift. This drift is slow and irreversible. If it is not calibrated regularly, the slope in the calculated pressure-frequency phase plane will shift, affecting the accuracy of impedance judgment. Self-calibration during downtime makes full use of the equipment's non-working time and reduces the cost of maintaining the pressure sensor.

[0041] The dynamically updated baseline compensation value is used in the calculation of the smooth pressure sequence after the next startup. Compensating the measurement system before each startup can keep the relative pressure change value output by the measurement system more accurate, improve the baseline stability of the impedance offset factor calculation in subsequent steps, and avoid false alarms of intake system blockage due to sensor drift.

[0042] In one embodiment, if the deviation value exceeds the preset allowable range, a sensor fault alarm signal can be output, and the update of the reference compensation value can be stopped.

[0043] When deviation value When the pressure exceeds, for example, 5 kPa, it usually means that the sensor has an anomaly such as diaphragm damage, short circuit, or acquisition module failure, rather than a simple zero drift. This can trigger an advanced alarm to indicate sensor failure and prevent incorrect calibration logic from further contaminating the data.

[0044] By comparing the preset allowable range with the deviation value, and stopping the update of the benchmark compensation value when the deviation value exceeds the preset allowable range, the continued propagation of erroneous parameters can be prevented, ensuring timely mitigation of losses in the event of hardware failure.

[0045] In step S102, when the rate of change of the smoothed frequency sequence exceeds a preset threshold, it is determined that the Roots blower has entered an active speed regulation cycle, and a two-dimensional phase plane is constructed based on the smoothed frequency sequence and the smoothed pressure sequence to calculate the characteristic area enclosed by the running trajectory in the active speed regulation cycle on the two-dimensional phase plane.

[0046] In one embodiment, the active speed regulation cycle includes a complete acceleration process and a complete deceleration process; calculating the characteristic area enclosed by the running trajectory in the two-dimensional phase plane within the active speed regulation cycle includes: for each complete acceleration and deceleration process within the active speed regulation cycle, traversing all sampling points, calculating the first product of the smoothing frequency of the current sampling point and the smoothing pressure of the next sampling point, and the second product of the smoothing frequency of the next sampling point and the smoothing pressure of the current sampling point; calculating the difference between the first product and the second product, and accumulating the differences corresponding to all adjacent sampling points within the entire active speed regulation cycle, and determining the characteristic area based on the absolute value of the accumulation result.

[0047] The active speed regulation cycle of a Roots blower refers to the process by which the blower adjusts from one steady-state speed to another, or performs periodic purging actions, in order to adapt to changes in dissolved oxygen demand in the biological treatment tank. The rate of change of the smooth frequency sequence can be monitored in real time. When the absolute value of the rate of change of the smooth frequency sequence exceeds, for example, 0.5 Hz / s, it can be marked as the start of the active speed regulation of the Roots blower.

[0048] The constructed two-dimensional phase plane has smooth frequency as the X-axis and smooth pressure as the Y-axis. Under ideal rigid transmission, the change of pressure with frequency should be a more coincident curve. However, in the case of belt slack, the pressure response during acceleration will lag behind the increase in frequency, and the pressure drop during deceleration will also lag, thus forming a closed hysteresis loop on the phase plane.

[0049] The characteristic area can be calculated using the discretized form of Green's theorem, assuming the sampling point sequence is... The calculation process is as follows: , as well as The values ​​are the smoothing frequency and smoothing pressure at the i-th time step, respectively.

[0050] Traditional single-point monitoring usually only focuses on the magnitude of the pressure value, while ignoring the dynamic phase relationship between pressure and rotational speed. In wastewater treatment plants, belt slack in Roots blowers is a gradual process. In the early stages, belt slack in Roots blowers is only manifested as a decrease in transmission efficiency, that is, the pressure does not increase accordingly after the rotational speed increases. By constructing a phase plane and calculating the area, this implicit time lag can be transformed into an explicit geometric area, thus enabling the amplification and extraction of the existing fault characteristics.

[0051] The physical meaning of the characteristic area corresponds to the energy dissipation or mechanical clearance of the transmission system within a speed regulation cycle; the looser the belt, the more severe the slippage, and the wider the hysteresis loop, the larger the obtained characteristic area; compared with simple instantaneous value comparison, the integral area has stronger noise resistance, avoids the influence of individual sampling points on the overall area, and thus ensures the stability and sensitivity of belt slack fault judgment.

[0052] Figure 2 This is a schematic diagram of the feature area under different conditions in the embodiments of this application, such as... Figure 2 As shown, the feature area obtained when the Roots blower is in a healthy state is smaller; the feature area obtained when the Roots blower has a loose drive belt is larger; when the Roots blower has a clogged air intake filter, it is difficult to show anomalies in the feature area, but the feature area in the two-dimensional phase plane is different from that in the healthy state. The regression slope can be combined to further determine whether there are any anomalies in the Roots blower.

[0053] In step S103, the regression slopes of the smoothed frequency sequence and the smoothed pressure sequence within the active speed regulation cycle are calculated, and the impedance offset factor of the regression slope relative to the reference slope is determined.

[0054] In one embodiment, calculating the regression slope of the smoothed frequency sequence and the smoothed pressure sequence within the active speed regulation period includes: determining the pressure arithmetic mean of the smoothed pressure sequence and the frequency arithmetic mean of the smoothed frequency sequence within the active speed regulation period; calculating the pressure deviation between the smoothed pressure and the pressure arithmetic mean at each sampling point, and the frequency deviation between the smoothed frequency and the frequency arithmetic mean at each sampling point; using the sum of the products of the pressure deviation and the frequency deviation at all sampling points as the covariance term, the sum of the squares of the frequency deviations at all sampling points as the variance term, and the ratio of the covariance term to the variance term as the regression slope.

[0055] Let the mean of the smoothed frequency be Smoothed mean pressure is For each sampling point They can be calculated separately. and regression slope Impedance offset factor The regression slope can be calculated. relative to factory reference slope Obtained by ratio or difference, for example .

[0056] Roots blowers are positive displacement blowers. The outlet pressure of a Roots blower mainly depends on the back pressure, i.e., the water depth of the aeration head and the pipeline resistance. Under constant water level, the pressure and flow rate of a Roots blower are linearly related. When the inlet filter is clogged, the resistance at the intake end of the Roots blower increases, which leads to a decrease in the efficiency of the Roots blower in doing work at the same frequency or a shift in the characteristic curve.

[0057] The regression slope reflects the aerodynamic impedance characteristics of the system composed of the current Roots blower and pipeline network. When intake blockage occurs, the airflow is obstructed, making it difficult to establish effective exhaust pressure or changing its characteristics at the same speed increase, causing the regression slope to deviate from the reference value. The characteristics of the regression slope are orthogonal to the hysteresis loop area caused by belt slack, that is, belt slack mainly affects the area of ​​the phase trajectory, while intake blockage mainly affects the inclination of the phase trajectory.

[0058] In step S104, the characteristic area and impedance offset factor are input into the multidimensional nonlinear fusion model. By performing nonlinear activation on the characteristic area and combining it with the linear superposition of the impedance offset factor, the transmission anomaly index of the Roots blower is calculated, so as to output the inspection results of the Roots blower based on the transmission anomaly index.

[0059] In one embodiment, the transmission anomaly index of the Roots blower is determined by the following formula: ,in, This refers to the transmission anomaly index of the Roots blower. It is a natural constant. The preset gain coefficient, For the characteristic area, The preset area threshold, The preset weighting coefficients, This is the impedance offset factor. This is the standard impedance constant used for normalization.

[0060] The preset gain coefficient, for example, is set to 0.5, to adjust the steepness of the activation function; the preset area threshold can be preset based on the hysteresis area of ​​a normal new belt; the preset weight coefficient, for example, is set to 0.8, to balance the influence of the impedance offset factor.

[0061] The calculation formula for the transmission anomaly index of a Roots blower is a multidimensional nonlinear fusion model. The first term of the calculation formula for the transmission anomaly index... It is a variant of the Sigmoid activation function used to handle feature area; the second term in the formula for calculating the transmission anomaly index. It is a linear term used to handle the impedance offset factor.

[0062] Belt slack faults in Roots blowers often exhibit abrupt or threshold characteristics. When the slack is within a certain range, the belt of the Roots blower can maintain effective transmission thanks to the automatic tensioning device; however, when the slack exceeds the critical point, slippage will occur rapidly. Therefore, a Sigmoid nonlinear activation is applied to the characteristic area, so that when the characteristic area... When the first term of the formula for calculating the transmission anomaly index is close to 0, it can suppress any possible noise.

[0063] The formula for calculating the transmission anomaly index integrates the fault characteristics of two different physical properties into a dimensionless index, by adjusting... and The sensitivity to belt slack can be flexibly set, and can be adjusted... You can set the focus weight for congestion faults.

[0064] The higher the value of the transmission anomaly index obtained, the lower the overall health of the Roots blower. It retains both the ability to detect sudden mechanical failures and the ability to track the trend of progressive air circuit failures, thus achieving a comprehensive evaluation of the health status of the Roots blower.

[0065] In one embodiment, the inspection results of the Roots blower are output based on the transmission abnormality index, including: comparing the transmission abnormality index of the Roots blower with a preset alarm threshold to determine whether there is an abnormality in the transmission of the Roots blower; if it is determined that there is an abnormality in the transmission of the Roots blower, the fault type of the Roots blower is determined based on the contribution weight of the characteristic area and impedance offset factor to the transmission abnormality index of the Roots blower.

[0066] Figure 3 This is a comparative diagram of the test results and pressure alarm monitoring results of this application, as shown below. Figure 3 As shown, when monitoring the Roots blower solely by pressure, the pressure peak of the Roots blower varies under different operating conditions, but it may not output an alarm signal because the predetermined pressure alarm threshold has not been reached. By utilizing the method for determining the transmission abnormality index in this embodiment, alarms can be effectively triggered when the Roots blower is in abnormal condition, thus enabling effective inspection of the Roots blowers on the wastewater treatment production line.

[0067] In one embodiment, the transmission abnormality index of the Roots blower is determined based on a nonlinear activation term of the characteristic area and a linear superposition term of the impedance offset factor. When an abnormality is determined in the transmission of the Roots blower, the fault type is determined as follows: if the ratio of the nonlinear activation term to the linear superposition term is greater than or equal to a predetermined ratio, the fault type is determined to be abnormally loose drive belt; if the ratio of the nonlinear activation term to the linear superposition term is less than a predetermined ratio, the fault type is determined to be air intake system blockage.

[0068] A total alarm threshold can be set, for example, to 1.5. If the transmission abnormality index of the Roots blower is greater than or equal to the total alarm threshold, the abnormality judgment logic can be triggered, and the nonlinear term can be calculated. With linear terms The ratio; if the ratio is greater than or equal to the predetermined ratio, it indicates that the increase in the transmission abnormality index of the Roots blower is mainly contributed by the nonlinear activation term; if the ratio is less than the predetermined ratio, it indicates that the increase in the transmission abnormality index of the Roots blower is mainly contributed by the linear superposition term.

[0069] By classifying by ratio, specific instructions can be output to suggest checking the belt or cleaning the air inlet, which facilitates targeted handling of existing faults at the wastewater treatment site.

[0070] Since belt slack primarily causes an increase in the characteristic area, with a smaller impact on the hysteresis loop area; and blockage primarily causes a change in the regression slope, with a smaller impact on the hysteresis loop area, therefore, the ratio It has high recognizability and can provide definitive decision support for on-site maintenance.

[0071] Figure 4 This is a schematic diagram illustrating the structure of a real-time inspection system 1000 for wastewater treatment process data, according to an exemplary embodiment. (Refer to...) Figure 4 The wastewater treatment process data real-time inspection system 1000 includes a processor 1100 and a memory 1200. The memory 1200 stores computer program instructions. When the computer program instructions are executed by the processor 1100, they implement all or part of the steps of the wastewater treatment process data real-time inspection method in this application.

[0072] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only.

[0073] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope.

Claims

1. A sewage treatment process data real-time inspection method, characterized in that, The method comprises the following steps: For the Roots blower on the sewage treatment production line, the frequency signal and the pressure signal are smoothed and aligned to obtain a smoothed frequency sequence and a smoothed pressure sequence; When the rate of change of the smoothed frequency sequence exceeds a preset threshold, it is determined that the Roots blower enters an active speed regulation period, and a two-dimensional phase plane is constructed based on the smoothed frequency sequence and the smoothed pressure sequence to calculate a characteristic area enclosed by the running track in the two-dimensional phase plane in the active speed regulation period; The regression slope of the smoothed frequency sequence and the smoothed pressure sequence in the active speed regulation period is calculated, and an impedance offset factor of the regression slope relative to a reference slope is determined; The characteristic area and the impedance offset factor are input into a multi-dimensional nonlinear fusion model, the transmission abnormality index of the Roots blower is calculated by nonlinear activation of the characteristic area and linear superposition of the impedance offset factor, and the patrol result of the Roots blower is output according to the transmission abnormality index; The transmission abnormality index of the Roots blower is determined by the following formula: wherein, is a drive abnormality index of the Roots blower, is a natural constant, is a preset gain coefficient, is a characteristic area, is a preset area threshold value, is a preset weight coefficient, is an impedance offset factor, is a standard impedance constant for normalization.

2. The real-time inspection method of sewage treatment process data according to claim 1, characterized in that, The active speed regulation period includes a complete acceleration process and a complete deceleration process; The characteristic area enclosed by the running track in the two-dimensional phase plane in the active speed regulation period comprises: For each complete acceleration and deceleration process in the active speed regulation period, all sampling points are traversed, the first product of the smoothed frequency of the current sampling point and the smoothed pressure of the next sampling point is calculated, and the second product of the smoothed frequency of the next sampling point and the smoothed pressure of the current sampling point is calculated; The difference between the first product and the second product is calculated, and the difference values corresponding to all adjacent sampling points in the entire active speed regulation period are accumulated, and the characteristic area is determined according to the absolute value of the accumulation result.

3. The real-time inspection method of sewage treatment process data according to claim 1, characterized in that, The regression slope of the smoothed frequency sequence and the smoothed pressure sequence in the active speed regulation period comprises: The arithmetic mean of the smoothed pressure sequence and the arithmetic mean of the smoothed frequency sequence in the active speed regulation period are determined, the pressure deviation of each sampling point from the arithmetic mean of the smoothed pressure is calculated, and the frequency deviation of each sampling point from the arithmetic mean of the smoothed frequency is calculated; The sum of the products of the pressure deviations and the frequency deviations of all sampling points is taken as the covariance term, the sum of the squares of the frequency deviations of all sampling points is taken as the variance term, and the ratio of the covariance term to the variance term is taken as the regression slope.

4. The real-time inspection method of sewage treatment process data according to claim 1, characterized in that, The patrol result of the Roots blower is output according to the transmission abnormality index, which comprises: The transmission abnormality index of the Roots blower is compared with a pre-set alarm threshold to determine whether the transmission of the Roots blower is abnormal; In the case where it is determined that the transmission of the Roots blower is abnormal, the contribution weight of the characteristic area and the impedance offset factor to the transmission abnormality index of the Roots blower is determined to determine the fault type of the Roots blower.

5. The real-time inspection method of sewage treatment process data according to claim 4, characterized in that, The transmission abnormality index of the Roots blower is determined according to the nonlinear activation term of the characteristic area and the linear superposition term of the impedance offset factor; in the case where it is determined that the transmission of the Roots blower is abnormal, the fault type of the Roots blower is determined by the following method: In the case where the ratio of the nonlinear activation term to the linear superposition term is greater than or equal to a predetermined proportion, it is determined that the fault type of the Roots blower is transmission belt abnormal relaxation. In a case that a ratio of the nonlinear activation term to the linear superposition term is less than a predetermined proportion, the fault type of the Roots blower is determined as an intake system blockage.

6. The real-time inspection method of wastewater treatment process data according to claim 1, characterized in that, A change rate of the smoothed frequency sequence is determined by calculating a difference of the smoothed frequency in adjacent time windows; the smoothed pressure sequence is determined in the following way: The discrete pressure signal of the Roots blower is calculated by using a time decay weight to obtain pressure data; the time decay weight is positively correlated with a time difference between the current time; The pressure data calculated by using the weighted moving average is corrected by using a linear correction coefficient of the pressure sensor and a reference compensation value based on the current atmospheric pressure environment to generate the smoothed pressure sequence.

7. The real-time inspection method of sewage treatment process data according to claim 6, characterized in that, The method further comprises: In response to the Roots blower receiving a shutdown instruction and the operating frequency being zeroed, the feedback value of the pressure sensor is collected within a preset delay period; A deviation value between the feedback value and the standard atmospheric pressure is calculated, if the deviation value is within a preset allowable range, the reference compensation value is updated according to the deviation value, and the updated reference compensation value is used to participate in the calculation of the smoothed pressure sequence at a subsequent time.

8. The real-time inspection method of sewage treatment process data according to claim 7, characterized in that, The method further comprises: if the deviation value exceeds the preset allowable range, outputting a sensor fault alarm signal and stopping updating the reference compensation value.

9. A sewage treatment process data real-time inspection system, characterized in that, Comprise: A processor and a memory, the memory stores computer program instructions, the computer program instructions are executed by the processor to realize the sewage treatment process data real-time inspection method according to any one of claims 1-8.

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