A lead electrolytic cell voltage on-line intelligent monitoring method and system

Abstract

The application relates to the technical field of electrolytic cell monitoring, in particular to a lead electrolytic cell voltage online intelligent monitoring method and system, which comprises the following steps: collecting the cell voltage, electrolyte voltage and electrolyte temperature of a lead electrolytic cell at each moment in a monitoring interval; determining the induced common-mode interference condition of the monitoring interval, obtaining the electrolysis high-temperature interference condition of the monitoring interval; combining the induced common-mode interference condition and the electrolysis high-temperature interference condition to obtain a voltage interference factor of the monitoring interval; and respectively correcting the anode voltage drop, cathode voltage drop and electrolyte voltage drop of the lead electrolytic cell to evaluate the lead electrolytic cell voltage monitoring condition. Therefore, the accuracy and reliability of the lead electrolytic cell voltage monitoring are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrolytic cell monitoring, in particular to a lead electrolytic cell voltage online intelligent monitoring method and system. BACKGROUND

[0002] The lead electrolytic cell voltage is a key control technical index in the lead hydrometallurgy industry field. Through real-time acquisition, transmission and analysis of the voltage data of the electrolytic cell, intelligent monitoring and optimization of the hydrometallurgy process are realized. If the electrolytic cell voltage is too high, the impurity metals below lead in the electrochemical series will be dissolved and deposited on the cathode, affecting the chemical quality of the cathode lead and intensifying the consumption of electric energy. If the electrolytic cell voltage is too low, the cathode lead will be deposited coarsely or even stop, and the reaction kinetics will be limited, prompting other metal ions to be deposited on the cathode, affecting the purity of the cathode lead.

[0003] In the lead hydrometallurgy process, the electrolysis workshop site is in a strong current, high magnetic field and complex temperature fluctuation environment. The traditional lead electrolytic cell voltage online monitoring technology will cause electromagnetic induction due to the influence of the strong electromagnetic field environment of the electrolysis workshop. The alternating magnetic field will generate eddy current in the conductor, and the conductor eddy current and Lorentz force generated by the strong electromagnetic field will cause the voltage monitoring data of the lead electrolytic cell to drift seriously. At the same time, the electrolytic reaction of the electrolytic cell and the operation of the smelting workshop will generate high temperature, which will change the conductivity of the electrolyte, amplify the temperature drift and gain error risk in the lead electrolytic cell voltage monitoring data, and cause obvious lag and distortion in the lead electrolytic cell voltage monitoring data, so that the voltage anomaly of the lead electrolytic cell cannot be found in time, which may cause local overheating of the electrolytic cell equipment, electrolyte spatter and even plate ablation, and cause safety accidents. SUMMARY

[0004] In order to solve the above technical problems, the purpose of the present application is to provide a lead electrolytic cell voltage online intelligent monitoring method and system, and the technical scheme adopted is as follows:

[0005] In the first aspect, the present application provides a lead electrolytic cell voltage online intelligent monitoring method, which comprises the following steps:

[0006] Collecting the cell voltage, electrolyte voltage and electrolyte temperature of the lead electrolytic cell at each time in the monitoring interval;

[0007] Based on the peak distribution of the cell voltage in the monitoring interval, the monitoring interval is divided into each local period, the periodic similarity of the cell voltage between any two local periods in the monitoring interval is analyzed, and the trend distribution of the peak is analyzed. Combined with the distribution disorder degree of the low frequency component and the energy attenuation degree of the high frequency component of the electrolyte voltage in the frequency domain in the monitoring interval, the induced common mode interference condition of the monitoring interval is determined;

[0008] respectively, analyze the hysteresis of the electrolyte voltage mutation point relative to the electrolyte temperature mutation point in time sequence, and the change trend of the electrolyte temperature mutation point, determine the electrolytic high temperature interference condition of the monitoring interval combined with the trend correlation between the electrolyte temperature mutation point and the electrolyte voltage mutation point;

[0009] Combined with the induced common mode interference condition and the electrolytic high temperature interference condition, the voltage interference factor of the monitoring interval is obtained, and the anode voltage drop, the cathode voltage drop and the electrolyte voltage drop of the lead electrolysis cell are respectively corrected to evaluate the voltage monitoring condition of the lead electrolysis cell.

[0010] In one of the embodiments, the division of the monitoring interval into local time periods includes:

[0011] Using a peak detection algorithm, each wave crest in the cell voltage at all times in the monitoring interval is obtained, and each local time period is obtained by taking the time corresponding to the wave crest as the division point.

[0012] In one of the embodiments, the determination of the induced common mode interference condition of the monitoring interval includes:

[0013] The Hurst index of the sequence composed of all wave crest data of the cell voltage in the monitoring interval is calculated, and the cumulative sum of the phase locking value of the cell voltage between any two local time periods in the monitoring interval is calculated; combined with the Hurst index and the cumulative sum, the periodic fluctuation of the cell voltage of the monitoring interval is obtained.

[0014] Using a signal decomposition algorithm, the electrolyte voltage of the monitoring interval is divided into high-frequency sub-signals and low-frequency sub-signals; the information entropy of all components of all low-frequency sub-signals is calculated; the slope of the fitting straight line of each high-frequency sub-signal is obtained; and the reciprocal of the slope is taken as the energy attenuation rate of each high-frequency sub-signal.

[0015] Combined with the information entropy and the energy attenuation rate of all high-frequency sub-signals, the coupling dielectric interference of the monitoring interval is obtained.

[0016] The induced common mode interference condition of the monitoring interval is the fusion result of the periodic fluctuation of the cell voltage and the coupling dielectric interference.

[0017] In one of the embodiments, the periodic fluctuation of the cell voltage is positively correlated with the Hurst index and the cumulative sum.

[0018] In one of the embodiments, the sum of the energy attenuation rates of all high-frequency sub-signals is calculated, and multiplied by the information entropy to obtain the coupling dielectric interference of the monitoring interval.

[0019] In one of the embodiments, the determination of the electrolytic high temperature interference condition of the monitoring interval includes:

[0020] The mutation points of the electrolyte voltage and the electrolyte temperature in the monitoring interval are respectively composed into time sequence, the cumulative result of the difference between the time of the electrolyte temperature mutation point and the time of the electrolyte voltage mutation point of all electrolyte temperature mutation points with the same bit sequence is calculated, and the cumulative result is multiplied by the Hurst index of the time sequence of the electrolyte temperature mutation point to obtain the change hysteresis of the electrolyte temperature and the voltage in the monitoring interval;

[0021] The trend items of the electrolyte temperature mutation point and the electrolyte voltage mutation point are respectively obtained by using a trend decomposition algorithm, and the correlation coefficient of the trend item of the electrolyte temperature mutation point and the trend item of the electrolyte voltage mutation point is calculated.

[0022] The negative correlation index mapping result of the correlation coefficient is fused with the change hysteresis to obtain the electrolytic high-temperature interference condition.

[0023] In one of the embodiments, the voltage interference factor is positively correlated with the induced common-mode interference condition and negatively correlated with the electrolytic high-temperature interference condition.

[0024] In one of the embodiments, the anode voltage drop, the cathode voltage drop and the electrolyte voltage drop of the lead electrolytic cell are respectively corrected, including:

[0025] The anode voltage drop average, the cathode voltage drop average and the electrolyte voltage drop average of the lead electrolytic cell measured in the monitoring interval are respectively calculated, and all are denoted as voltage drop average;

[0026] The absolute value of the difference between the voltage interference factor and the preset threshold value is calculated, and the product of the absolute value and each voltage drop average is calculated.

[0027] If the voltage interference factor is greater than the preset threshold value, the difference between each voltage drop average and the product is calculated as the corrected voltage drop average, otherwise, the sum of each voltage drop average and the product is calculated as the corrected voltage drop average.

[0028] In one of the embodiments, the lead electrolytic cell voltage monitoring condition is evaluated, including:

[0029] If the corrected voltage drop average is less than or equal to the corresponding rated voltage drop, it is determined that there is no abnormality in the monitored voltage during the operation of the lead electrolytic cell, otherwise, it is determined that there is an abnormality in the monitored voltage during the operation of the lead electrolytic cell.

[0030] In the second aspect, the embodiments of the present application also provide a lead electrolytic cell voltage online intelligent monitoring system, including a memory, a processor and a computer program stored in the memory and running on the processor, and the processor implements the steps of the method in any one of the above aspects when executing the computer program.

[0031] The present application has at least the following beneficial effects:

[0032] The application determines the induced common-mode interference condition of the monitoring interval by analyzing the peak trend of the electrolytic cell voltage, in combination with the low-frequency and high-frequency components in the frequency domain analysis of the electrolyte voltage, reflects the periodic drift of the cell voltage caused by the induced potential and common-mode interference in the strong electromagnetic environment during the operation of the lead electrolytic cell, and the degree of coupling dielectric interference of the electrolyte voltage, quantifies the possibility of false high of the lead electrolytic cell voltage monitoring, and improves the accuracy and reliability of the lead electrolytic cell voltage monitoring; further, the electrolytic high-temperature interference condition of the monitoring interval is determined, which reflects the change lag degree between the electrolyte temperature and the voltage caused by the influence of the electrolysis reaction heat and the high temperature in the smelting workshop during the operation of the lead electrolytic cell, and the negative correlation trend between the electrolyte voltage and temperature, by identifying and quantifying the influence of high-temperature interference, the possibility of false low of the lead electrolytic cell voltage monitoring is embodied, and the early warning ability of the electrolytic cell voltage fluctuation trend is enhanced; further, in combination with the induced common-mode interference condition and the electrolytic high-temperature interference condition, the voltage interference factor of the monitoring interval is obtained, which accurately reflects the induced potential and common-mode interference condition formed by the strong electromagnetic environment outside during the operation of the lead electrolytic cell, and the lag distortion condition of the electrolytic cell voltage monitoring data caused by high temperature, realizes the accurate correction of the anode voltage drop, the cathode voltage drop and the electrolyte voltage drop of the lead electrolytic cell, improves the accuracy and stability of the lead electrolytic cell voltage monitoring, and ensures the operation safety of the lead electrolytic cell. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the drawings needed in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0034] Figure 1 A step flow chart of a lead electrolytic cell voltage online intelligent monitoring method provided by an embodiment of the present application;

[0035] Figure 2 A flow chart for determining the induced common-mode interference condition of the monitoring interval;

[0036] Figure 3 A flow chart for determining the electrolytic high-temperature interference condition of the monitoring interval. DETAILED DESCRIPTION

[0037] In order to further illustrate the technical means and effects taken by the present application to achieve the predetermined object, the specific implementation, structure, features and effects of the lead electrolytic cell voltage online intelligent monitoring method and system according to the present application are described in detail as follows in combination with the drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.

[0039] The specific scheme of the lead electrolytic cell voltage online intelligent monitoring method and system provided by the present application is described in detail below in combination with the drawings.

[0040] Please refer to Figure 1 which shows the step flowchart of a lead electrolytic cell voltage online intelligent monitoring method provided by an embodiment of the present application. The method comprises the following steps:

[0041] S1, collect the cell voltage, electrolyte voltage and electrolyte temperature of the lead electrolytic cell at each time in the monitoring interval, and perform pretreatment.

[0042] The present application takes single lead electrolytic cell voltage monitoring as an example for subsequent processing. The voltage sensor is used to obtain the cell voltage applied between the anode and the cathode of the lead electrolytic cell and the electrolyte voltage through the connection of the multi-core signal line and the copper bar, and the electrolyte temperature data of the lead electrolytic cell is obtained in real time by deploying the temperature sensor. The cell voltage, electrolyte voltage data and electrolyte temperature data are collected synchronously, and the collection frequency is set to 10 Hz. The implementer can set it according to the actual situation, which is not limited in the present embodiment.

[0043] In order to prevent data loss caused by external environmental interference during data collection and the influence of different dimensions between different data on subsequent analysis, the above obtained lead electrolytic cell corresponding cell voltage data, electrolyte voltage data and electrolyte temperature data are subjected to missing value filling processing by using cubic spline interpolation method, and the dimension unification between the cell voltage data, electrolyte voltage data and electrolyte temperature data is realized by Z-Score standardization processing. Cubic spline interpolation method and Z-Score standardization are both known technologies, and the specific process is not described here.

[0044] S2, based on the peak distribution of the slot voltage in the monitoring interval, dividing the monitoring interval into each local period, analyzing the periodic similarity of the slot voltage between any two local periods in the monitoring interval, and the trend distribution of the peak, combining the distribution disorder degree of the low frequency component and the energy attenuation degree of the high frequency component of the electrolyte voltage in the frequency domain, to determine the induced common mode interference condition of the monitoring interval.

[0045] During the operation of the lead electrolytic cell, the alternating magnetic field generated by the Wan'an level DC bus and the high-frequency rectifier equipment according to Faraday's law of electromagnetic induction will generate millivolt-level induced potential in the sampling line ring, and will be in series with the real electrolytic cell voltage and the electrolyte voltage; and the common mode interference formed by the coupling of the high-frequency component to the signal amplifier input through the distributed capacitance will cause the lead electrolytic cell voltage monitoring data to drift and distort, aggravate the abnormal misjudgment of the lead electrolytic cell voltage monitoring data, and lead to the inability to timely grasp the real situation of the lead electrolytic cell voltage, affecting the quality of the cathode lead product and the reliable operation of the lead electrolytic cell equipment.

[0046] Specifically, during the operation of the lead electrolytic cell, when the induced potential or common mode interference formed by the influence of the external strong electromagnetic field environment is more serious, the influence of the strong electromagnetic field coupling effect on the current distribution makes the lead electrolytic cell voltage data more present obvious periodic disturbance condition, and the common mode voltage generated by the strong electromagnetic field in the grounding loop makes the change of the fluctuation peak value of the slot voltage data more have obvious trend; at the same time, the high impedance of the electrolyte loop is affected by the common mode current coupling, which leads to unstable ground potential and obvious low-frequency noise, and the high-frequency selective interference caused by the dielectric properties of the electrolyte will make the high-frequency component energy of the electrolyte voltage data decay faster.

[0047] Based on the above analysis, each monitoring interval is set in the embodiment, and the length of the monitoring interval is set to 10 minutes in the embodiment, and the implementer can set it according to the actual situation, which is not limited in the embodiment. Taking any one of the monitoring intervals as an example, the preprocessed slot voltage data in the monitoring interval is composed into a slot voltage data sequence in time sequence. The slot voltage data sequence of the lead electrolytic cell in the monitoring interval is taken as input, the AMPD (Automatic Multiscale-based Peak Detection) multiscale peak detection algorithm is used to obtain all the peak data in the slot voltage data sequence, and each peak data corresponding to the time is taken as a segmentation point. The monitoring interval is divided into each local period, and the slot voltage data in each local period is composed into a slot voltage sub-sequence.

[0048] Further, the PLV phase locking value between any two groove voltage sub-sequences in the monitoring interval is obtained by the PLV algorithm. The larger the PLV phase locking value is, the more similar the periods between the groove voltage sub-sequences are. Secondly, all wave peak data in the groove voltage data sequence in the monitoring interval are grouped to form a wave peak sequence, and the Hurst index of the wave peak sequence is calculated. The coupling dielectric interference of the monitoring interval is obtained by combining the Hurst index and the sum of the phase locking values between all arbitrary two local periods in the interval. The coupling dielectric interference is positively correlated with the Hurst index and the sum.

[0049] In the embodiment, the product of the Hurst index and the sum is taken as the groove voltage period fluctuation of the monitoring interval. The groove voltage period fluctuation reflects the fluctuation degree of the peak data of the groove voltage and the period similarity of the groove voltage data caused by the strong electromagnetic field coupling effect and the common-mode voltage generated by the grounding loop. In the running process of the lead electrolytic cell, the more serious the interference of the induced potential and the common-mode current formed by the external strong electromagnetic environment is, the more long-term trend the peak data in the groove voltage data sequence has, the higher the period similarity between the groove voltage sub-sequences in the monitoring interval is, and the larger the groove voltage period fluctuation of the monitoring interval is.

[0050] Further, the time sequence composed of all electrolyte voltages in the monitoring interval is divided into each frequency band by using the wavelet packet decomposition algorithm. In the embodiment, Daubechies 4 (db4) wavelet is used, and 3-level decomposition is performed to obtain each high-frequency sub-signal and each low-frequency sub-signal after decomposition. The information entropy of all components of all low-frequency sub-signals is calculated. The least square method is used to linearly fit each high-frequency sub-signal to obtain the slope of the fitting straight line of each high-frequency sub-signal. The reciprocal of the slope of the fitting straight line of each high-frequency sub-signal is taken as the energy attenuation rate of each high-frequency sub-signal. The wavelet packet decomposition algorithm is a known technology.

[0051] In the embodiment, the sum of the energy attenuation rates of all high-frequency sub-signals in the monitoring interval is calculated, and multiplied by the information entropy to obtain the coupling dielectric interference of the monitoring interval. The coupling dielectric interference represents the difference of the low-frequency sub-signals and the rapid energy attenuation degree of the high-frequency sub-signals caused by the common-mode current of the strong electromagnetic environment and the dielectric characteristic interference of the electrolyte in the running process of the lead electrolytic cell. The more obvious the energy difference of the frequency components in the low-frequency band is, the greater the degree of confusion is, and the greater the energy attenuation rate of the frequency components in the high-frequency band is, the stronger the coupling dielectric interference of the monitoring interval is.

[0052] The fusion of the slot voltage periodic fluctuation and the coupling dielectric interference determines the induced common mode interference condition of the monitoring interval, which is used to represent the periodic drift of the slot voltage and the coupling dielectric interference degree of the electrolyte voltage caused by the induced potential and the common mode interference formed by the strong electromagnetic environment in the lead electrolytic cell running process. The more significant the induced common mode interference condition is, the more likely it is to cause false high phenomenon of lead electrolytic cell voltage monitoring and larger error.

[0053] It should be noted that fusion means combining multiple variables, which can be calculated by addition, multiplication, addition and multiplication fusion, and mean value calculation, and the present embodiment does not limit this.

[0054] In the present embodiment, the expression of the induced common mode interference condition of the monitoring interval is:

[0055] In the formula, is the induced common mode interference condition of the i th monitoring interval in the lead electrolytic cell running process, is the slot voltage periodic fluctuation of the i th monitoring interval in the lead electrolytic cell running process, is the coupling dielectric interference of the i th monitoring interval in the lead electrolytic cell running process, and norm() is a normalization function, so that the value of is in the range of [0, 1]. The flow chart of the induced common mode interference condition of the monitoring interval is shown in Figure 2 .

[0056] S3, respectively, the mutation points of the electrolyte voltage and the electrolyte temperature in the monitoring interval are obtained, the time sequence hysteresis of the electrolyte voltage mutation point relative to the electrolyte temperature mutation point is analyzed, and the change trend of the electrolyte temperature mutation point is analyzed. Combined with the trend correlation between the electrolyte temperature mutation point and the electrolyte voltage mutation point, the electrolytic high temperature interference condition of the monitoring interval is determined.

[0057] In the lead electrolytic cell running process, the electrolytic reaction of the electrolytic cell and the running of the smelting workshop will produce high temperature influence. The temperature drift and gain error analysis of the external high temperature environment on the lead electrolytic cell voltage monitoring data is difficult to accurately grasp the distortion degree of the lead electrolytic cell voltage monitoring data, so as to cover up the real condition of the electrolytic cell voltage and aggravate the risk of safety accidents.

[0058] Specifically, during the operation of the lead electrolytic cell, when the external environment interference caused by the electrolysis reaction and the high temperature generated in the smelting workshop on the voltage data monitoring of the electrolytic cell is more serious, the electrolyte temperature gradient rises obviously, and is affected by the need for a certain time of temperature transfer, the electrolyte voltage data is more significantly affected by the temperature and the related changes lagged by the temperature; at the same time, the electrolyte temperature rise will cause the ohmic voltage drop and the polarization voltage drop of the electrolyte, and when the external environment high temperature interference is more serious, the negative correlation between the trend change of the electrolyte voltage data and the electrolyte temperature data is higher.

[0059] Based on the above analysis, in this embodiment, all the electrolyte temperatures at all times in the monitoring interval are combined into an electrolyte temperature data sequence, and the electrolyte voltage data sequence and the electrolyte temperature data sequence in the monitoring interval are respectively taken as inputs, and the Pettitt mutation point detection algorithm is used to obtain each mutation point in the electrolyte voltage data sequence and the electrolyte temperature data sequence in the monitoring interval. The mutation points in the electrolyte voltage data sequence are combined into an electrolyte voltage mutation point sequence according to the order of appearance, and the mutation points in the electrolyte temperature data sequence are combined into an electrolyte temperature mutation point sequence according to the order of appearance. The electrolyte voltage mutation point sequence and the electrolyte temperature mutation point sequence are respectively taken as inputs, and the STL (Seasonal-Trend decomposition using Loess) sequence decomposition algorithm is used to obtain the trend items of each mutation point in the electrolyte voltage mutation point sequence and the trend items of each mutation point in the electrolyte temperature mutation point sequence. The Pettitt mutation point detection algorithm and the STL sequence decomposition algorithm are both known technologies, and the specific obtaining process will not be described in more detail.

[0060] Further, this embodiment determines the electrolytic high temperature interference condition of the monitoring interval, which is used to represent the change lag degree between the electrolyte temperature and the voltage and the negative correlation trend between the electrolyte voltage and the temperature caused by the electrolysis reaction heat and the high temperature in the smelting workshop during the operation of the lead electrolytic cell. Specifically:

[0061] For the electrolyte temperature mutation point sequence and the electrolyte voltage mutation point sequence, the difference between the time of the electrolyte temperature mutation point and the electrolyte voltage mutation point with the same bit sequence in the electrolyte temperature mutation point sequence and the electrolyte voltage mutation point sequence is calculated. It should be noted that the same bit sequence refers to the bit sequence in the electrolyte temperature mutation point sequence and the electrolyte voltage mutation point sequence. The cumulative result of all the differences in the monitoring interval is calculated, and multiplied by the Hurst index of the electrolyte temperature mutation point sequence to obtain the change hysteresis of the electrolyte temperature and voltage in the monitoring interval. The change hysteresis reflects the positive correlation trend of the electrolyte temperature in the lead electrolytic cell running process and the change hysteresis degree between the electrolyte temperature and the electrolyte voltage data. In the lead electrolytic cell running process, when the lead electrolytic cell voltage monitoring data is more seriously affected by the external environment electrolysis reaction or smelting workshop high temperature, the electrolyte temperature gradient rising condition is more obvious, and the hysteresis between the electrolyte temperature and voltage mutation data is more significant, that is, the change hysteresis obtained is larger.

[0062] The Pearson correlation coefficient of all trend items of the electrolyte temperature mutation point sequence and all trend items of the electrolyte voltage mutation point sequence is calculated, and the negative correlation index mapping result of the Pearson correlation coefficient is fused with the change hysteresis to obtain the electrolytic high temperature interference condition. The implementer can select other feasible correlation calculation methods such as cosine similarity.

[0063] The expression of the electrolytic high temperature interference condition of the monitoring interval in the embodiment is:

[0064] In the formula, is the electrolytic high temperature interference condition of the i th monitoring interval in the lead electrolytic cell running process; is the change hysteresis of the electrolyte temperature and voltage in the i th monitoring interval in the lead electrolytic cell running process; is the Pearson correlation coefficient in the i th monitoring interval in the lead electrolytic cell running process, e is a natural constant, and norm() is a normalization function, so that the value range of is in the range of [0, 1]. Wherein, is the index mapping result of the Pearson correlation coefficient, which aims to avoid the denominator being 0, is the negative correlation index mapping result of the Pearson correlation coefficient, which indicates that the electrolytic high temperature interference condition and the Pearson correlation coefficient are negatively correlated. The electrolytic high temperature interference condition determination flow chart of the monitoring interval is as Figure 3 shown.

[0065] The electrolytic high-temperature interference condition reflects the hysteresis of the change of the electrolyte temperature and voltage and the strength of the negative correlation between the electrolyte voltage and temperature caused by the heat of the electrolysis reaction and the high temperature in the smelting workshop during the operation of the lead electrolytic cell; the higher the negative correlation between the trend changes of the electrolyte voltage data and the electrolyte temperature data, the smaller the Pearson correlation coefficient, the more obvious the negative trend between the electrolyte voltage and temperature data caused by the high temperature during the operation of the lead electrolytic cell, and the greater the electrolytic high-temperature interference condition, at this time, it is easier to cause the false low phenomenon of the lead electrolytic cell voltage monitoring, and there is also a large error.

[0066] S4, in combination with the induced common-mode interference condition and the electrolytic high-temperature interference condition, obtains a voltage interference factor of the monitoring interval, and respectively corrects the anode voltage drop, the cathode voltage drop and the electrolyte voltage drop of the lead electrolytic cell to evaluate the lead electrolytic cell voltage monitoring condition.

[0067] During the operation of the lead electrolytic cell, the more serious the induced potential and common-mode interference formed by the strong electromagnetic environment outside, the easier it is to cause the false high phenomenon of the lead electrolytic cell voltage monitoring, that is, the measured value will abnormally increase, and the more serious the high temperature generated by the electrolysis reaction and the smelting workshop, the easier it is to cause the false low phenomenon of the lead electrolytic cell voltage monitoring, that is, the measured value will abnormally decrease, and the greater the induced common-mode interference condition and the electrolytic high-temperature interference condition of the monitoring interval, which all reflect that the higher the influence of the environment interference on the lead electrolytic cell voltage.

[0068] Therefore, in this embodiment, the induced common-mode interference condition and the electrolytic high-temperature interference condition of the monitoring interval are taken as the input of the TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) comprehensive evaluation method, and the comprehensive evaluation value is output, wherein the induced common-mode interference condition is positively correlated with the output comprehensive evaluation value, and the electrolytic high-temperature interference condition is negatively correlated with the output comprehensive evaluation value. The weight in the TOPSIS comprehensive evaluation method is determined by the entropy weight method. The TOPSIS comprehensive evaluation method and the entropy weight method are both known technologies, and the specific process will not be described here.

[0069] The normalized value of the comprehensive evaluation value is taken as the voltage interference factor of the monitoring interval, that is, the voltage interference factor is positively correlated with the induced common-mode interference condition and negatively correlated with the electrolytic high-temperature interference condition, the greater the voltage interference factor, the more likely the lead electrolytic cell voltage monitoring is false high, and vice versa, the more likely the lead electrolytic cell voltage monitoring is false low. The normalization method of the comprehensive evaluation value adopts the sigmoid function, and the implementer can choose other feasible normalization methods.

[0070] In the monitoring interval, the anode voltage drop, the cathode voltage drop, and the electrolyte voltage drop of the lead electrolytic cell are measured multiple times, respectively, the mean value of all the measured anode voltage drops, the mean value of all the measured cathode voltage drops, and the mean value of the measured electrolyte voltage drop are calculated, and the three mean values are all recorded as the voltage drop mean value.

[0071] The embodiment predefines a threshold T, which represents the critical judgment value of the false high and false low of the lead electrolytic cell voltage monitoring, and T = 0.5 in the embodiment, which can be set by the implementer according to the actual situation, and the embodiment does not limit this. The absolute value of the difference between the voltage interference factor of the monitoring interval and the threshold T is calculated, and the multiplication result of the absolute value and each voltage drop mean value is calculated, which represents the abnormal part of each voltage drop mean value. Further, if the voltage interference factor of the monitoring interval is greater than the threshold T, it indicates that the false high phenomenon occurs in the lead electrolytic cell voltage monitoring, the difference between each voltage drop mean value and the multiplication result is calculated as the corrected voltage drop mean value, and if the voltage interference factor of the monitoring interval is less than or equal to the threshold T, it indicates that the false low phenomenon occurs in the lead electrolytic cell voltage monitoring, and the sum of each voltage drop mean value and the multiplication result is calculated as the corrected voltage drop mean value.

[0072] The corrected voltage drop mean value eliminates the influence of the external strong electromagnetic environment and high temperature during the operation of the lead electrolytic cell, and obtains a more accurate voltage drop.

[0073] If the corrected voltage drop mean value is less than or equal to the corresponding rated voltage drop, it is determined that there is no abnormality in the monitored voltage during the operation of the lead electrolytic cell, otherwise, it is determined that there is an abnormality in the monitored voltage during the operation of the lead electrolytic cell, which needs to be maintained and repaired to avoid aggravating the fault evolution of the lead electrolytic cell over time and causing safety accidents. In the embodiment, the anode voltage drop is 0.34 V, the electrolyte voltage drop is 1.57 V, and the cathode voltage drop is 0.36 V.

[0074] Based on the same inventive concept as the above method, the embodiment of the present application also provides a lead electrolytic cell voltage online intelligent monitoring system, which comprises a memory, a processor, and a computer program stored in the memory and running on the processor, and the processor implements the steps of any one of the above methods when executing the computer program.

[0075] It should be noted that the above-mentioned sequence of the embodiments of the present application is only for description, and does not represent the advantages and disadvantages of the embodiments. Moreover, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multi-task processing and parallel processing are also possible or can be advantageous.

[0076] The various embodiments in the specification are described in progressive manner, and the same or similar parts between the various embodiments can be mutually referred to, and each embodiment focuses on the difference from other embodiments.

[0077] The above only describes the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for online intelligent monitoring of voltage in a lead electrolytic cell, characterized in that, The method includes the following steps: The cell voltage, electrolyte voltage, and electrolyte temperature of the lead electrolytic cell were collected at various times within the monitoring interval. Based on the peak distribution of the tank voltage within the monitoring interval, the monitoring interval is divided into various local time periods. The periodic similarity of the tank voltage between any two local time periods within the monitoring interval, as well as the trend distribution of the peaks, are analyzed. Combined with the degree of disorder in the distribution of the low-frequency component and the degree of energy attenuation of the high-frequency component of the electrolyte voltage in the frequency domain within the monitoring interval, the induced common-mode interference status of the monitoring interval is determined. The abrupt change points of electrolyte voltage and electrolyte temperature within the monitoring interval were obtained respectively. The time lag of the abrupt change point of electrolyte voltage relative to the abrupt change point of electrolyte temperature, as well as the changing trend of the abrupt change point of electrolyte temperature, were analyzed. Based on the trend correlation between the abrupt change points of electrolyte temperature and electrolyte voltage, the electrolytic high temperature interference status in the monitoring interval was determined. By combining the inductive common-mode interference and the electrolytic high-temperature interference, the voltage interference factor in the monitoring range is obtained, and the anode voltage drop, cathode voltage drop, and electrolytic voltage drop of the lead electrolytic cell are corrected respectively to evaluate the voltage monitoring status of the lead electrolytic cell. The determination of the induced common-mode interference status within the monitoring range includes: Calculate the Hurst exponent of the sequence of all peak data of the tank voltage within the monitoring interval, and calculate the cumulative sum of the phase lock values ​​of the tank voltage between any two local time periods within the monitoring interval; combine the Hurst exponent and the cumulative sum to obtain the periodic fluctuation of the tank voltage within the monitoring interval. The electrolyte voltage in the monitoring interval is divided into high-frequency sub-signals and low-frequency sub-signals using a signal decomposition algorithm; the information entropy of all components of all low-frequency sub-signals is calculated; the slope of the fitted line of each high-frequency sub-signal is obtained; and the reciprocal of the slope is taken as the energy attenuation rate of each high-frequency sub-signal. By combining the information entropy with the energy attenuation rate of all high-frequency sub-signals, the coupling dielectric interference of the monitoring interval is obtained; The induced common-mode interference status in the monitoring interval is the result of the fusion of the tank voltage periodicity and the coupled dielectric interference; the tank voltage periodicity is positively correlated with the Hurst exponent and the cumulative sum. The determination of the electrolytic high-temperature interference status within the monitoring range includes: The abrupt changes in electrolyte voltage and electrolyte temperature within the monitoring interval are respectively composed into time series. The sum of the differences between the time of the electrolyte temperature abrupt change point and the time of the electrolyte voltage abrupt change point in all the same order is calculated and multiplied by the Hurst exponent of the time series of electrolyte temperature abrupt changes to obtain the lag of changes in electrolyte temperature and voltage within the monitoring interval. The trend terms of electrolyte temperature change points and electrolyte voltage change points are obtained by using the trend decomposition algorithm, and the correlation coefficient between the trend terms of electrolyte temperature change points and electrolyte voltage change points is calculated. The negative correlation index mapping result of the correlation coefficient is fused with the change lag to obtain the electrolytic high-temperature interference status; the voltage interference factor is positively correlated with the induced common-mode interference status and negatively correlated with the electrolytic high-temperature interference status.

2. The online intelligent monitoring method for lead electrolytic cell voltage as described in claim 1, characterized in that, The division of the monitoring interval into various local time periods includes: The peak detection algorithm is used to obtain the peaks of the slot voltage at all times within the monitoring interval. The time corresponding to the peak is used as the dividing point to obtain the local time periods of the monitoring interval.

3. The online intelligent monitoring method for lead electrolytic cell voltage as described in claim 1, characterized in that, The sum of the energy attenuation rates of all high-frequency sub-signals is calculated and multiplied by the information entropy to obtain the coupling dielectric interference of the monitoring interval.

4. The online intelligent monitoring method for lead electrolytic cell voltage as described in claim 1, characterized in that, The corrections to the anode voltage drop, cathode voltage drop, and electrolytic pressure drop of the lead electrolytic cell include: Calculate the average anode voltage drop, average cathode voltage drop, and average electrolytic voltage drop of the lead electrolytic cell within the monitoring interval, and record them as the average voltage drop. Calculate the absolute value of the difference between the voltage interference factor and the preset threshold, and calculate the product of the absolute value of the difference and the average value of each voltage drop; If the voltage interference factor is greater than a preset threshold, calculate the difference between the average voltage drop and the product, and use it as the corrected average voltage drop; otherwise, calculate the sum of the average voltage drop and the product, and use it as the corrected average voltage drop.

5. The online intelligent monitoring method for lead electrolytic cell voltage as described in claim 4, characterized in that, The assessment of the voltage monitoring status of the lead electrolytic cell includes: If the corrected average voltage drop is less than or equal to the corresponding rated voltage drop, it is determined that there is no abnormality in the monitoring voltage during the operation of the lead electrolytic cell; otherwise, it is determined that there is an abnormality in the monitoring voltage during the operation of the lead electrolytic cell.

6. A lead electrolytic cell voltage online intelligent monitoring system, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-5.

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