Electrolytic tank group electrical parameter on-line monitoring evaluation and fault positioning method and system

Abstract

The invention discloses an electrolytic bath group electrical parameter online monitoring evaluation and fault positioning method and system. The method comprises the following steps: S1, carrying out real-time data acquisition and preprocessing on the electrolytic cell to obtain a real-time parameter data set; s2, setting a fixed hard threshold and an adaptive threshold based on the real-time parameter data set; and S3, performing multi-dimensional fault diagnosis and positioning based on the fixed hard threshold and the adaptive threshold. According to the method, early-stage, accurate and intelligent anomaly detection and fault diagnosis and positioning of the electrolytic cell group are achieved, and optimal control over the electrolysis technological process is achieved through communication with the DCS.

Description

Technical Field

[0001] This invention belongs to the field of industrial process monitoring and fault diagnosis technology, specifically relating to a method and system for online monitoring, evaluation and fault location of electrical parameters of an electrolytic cell group. Background Technology

[0002] In non-ferrous metal smelting plants, electrolytic cells are the core production equipment, and a series typically consists of dozens to hundreds of cells. Traditional electrolysis process control can only monitor three electrical parameters: series current, series voltage, and average cell voltage. Traditional monitoring methods cannot monitor the cell voltage, electrolysis curve, decomposition voltage, and resistance of each electrolytic cell online; they cannot detect early abnormalities or faults in individual electrolytic cells based on real-time trends in electrical parameters, thus failing to promptly alert management personnel and take appropriate measures to prevent cell damage and extend service life; and they cannot optimize production process control, improve electrolysis efficiency, or stabilize cathode metal quality by monitoring changes in electrical parameters online. Summary of the Invention

[0003] To address the shortcomings of existing technologies, one of the objectives of this invention is to provide a method for online monitoring, evaluation, and fault location of electrical parameters of electrolytic cell groups, enabling early, accurate, and intelligent anomaly detection, fault diagnosis, and location of electrolytic cell groups, and achieving optimized control of the electrolysis process through communication with DCS.

[0004] The second objective of this invention is to provide a system for realizing online monitoring, evaluation, and fault location of the electrical parameters of the electrolytic cell group.

[0005] This invention provides a method for online monitoring, evaluation, and fault location of electrical parameters of an electrolytic cell group, comprising the following steps:

[0006] S1. Real-time data acquisition and preprocessing of the electrolytic cell to obtain a real-time parameter dataset;

[0007] S2. Based on the real-time parameter dataset, set a fixed hard threshold and an adaptive threshold;

[0008] S3. Perform multi-dimensional fault diagnosis and location based on fixed hard threshold and adaptive threshold.

[0009] In step S1, the real-time data includes the series current of the electrolytic cell, the voltage of each electrolytic cell, and the corresponding electrolytic cell number;

[0010] Step S1 is as follows:

[0011] The preset time window length and calculation period are used to collect the series current I of the electrolytic cells and the voltage of each electrolytic cell. , where i is the electrolytic cell number;

[0012] Using the least squares method, the VI electrolysis curves of each electrolytic cell are generated in real time through linear fitting, and expressed by the following formula: ;

[0013] Based on the electrolysis curve, determine the intersection point of the electrolysis curve and the voltage coordinate axis. and the slope of the electrolysis curve ;

[0014] Calculate the voltage residual sequence for each electrolytic cell; the voltage residual is the difference between the cell voltage collected in real time and the cell voltage predicted by the currently fitted electrolysis curve model, calculated using the following formula: Where V is the real-time collected electrolytic cell voltage; I is the real-time collected electrolytic cell current; R is the resistance; E is the decomposition voltage; and e is the electrolytic cell voltage residual.

[0015] In step S2, the fixed hard threshold includes a fixed hard threshold for alarming above cell voltage and a fixed hard threshold for alarming below cell voltage; the fixed hard threshold is based on the highest operating cell voltage of the electrolytic cell. With minimum operating tank voltage The calculation is performed using the following formula: ; ;in, A fixed hard threshold is set for the alarm on the slot voltage; A fixed hard threshold is set for alarms under slot voltage.

[0016] The adaptive thresholds include adaptive thresholds for residual alarms (both upward and downward), voltage alarms (both upward and downward), resistance alarms (both upward and downward), and resistance alarms (both downward and upward). Setting these adaptive thresholds includes the following steps:

[0017] Set the data acquisition time window length and update cycle for calculating the adaptive threshold;

[0018] Based on the real-time parameter dataset obtained in step S1, obtain the data sequence of residual e within the time window. Decompose the data sequence of voltage E Data sequence with resistor R ;

[0019] The data sequence for calculating residual e moving average Use the following formula to calculate: Where n is the total number of data points in the data sequence; Let j be the j-th data point in the data sequence containing the residual e;

[0020] Calculate the data sequence of the decomposed voltage E moving average Use the following formula to calculate: Where n is the total number of data points in the data sequence; This refers to the j-th data point in the data sequence for decomposing voltage E.

[0021] Data sequence for calculating resistance R moving average Use the following formula to calculate: Where n is the total number of data points in the data sequence; This is the j-th data point in the data sequence for resistor R;

[0022] The data sequence for calculating residual e Moving standard deviation Use the following formula to calculate: ;

[0023] The adaptive threshold for alarm on residuals is calculated using the following formula. : ;in, This is the residual sensitivity coefficient;

[0024] The adaptive threshold for alarm under residuals is calculated using the following formula. : ;

[0025] Calculate the data sequence of the decomposed voltage E Moving standard deviation Use the following formula to calculate: ;

[0026] The upper alarm adaptive threshold of the decomposition voltage E is calculated using the following formula. : ;in, To decompose the voltage sensitivity coefficient;

[0027] The lower alarm adaptive threshold of the decomposition voltage E is calculated using the following formula. : ;

[0028] Data sequence for calculating resistance R Moving standard deviation Use the following formula to calculate: ;

[0029] Calculate the adaptive alarm threshold on resistor R using the following formula. : ;in, This is the resistance sensitivity coefficient;

[0030] Calculate the adaptive alarm threshold under resistance R using the following formula. : ;

[0031] The adaptive threshold updates automatically according to the set update cycle.

[0032] Step S3 is as follows:

[0033] When the cell voltage of the electrolytic cell exceeds the set fixed hard threshold range, it is determined that the electrolytic cell is faulty and a red emergency audible and visual alarm signal is issued.

[0034] When the residual voltage of the electrolytic cell exceeds the upper residual alarm adaptive threshold or falls below the lower residual alarm adaptive threshold, it is determined that the electrolytic cell is abnormal and a yellow warning signal is issued.

[0035] When the decomposition voltage E of the electrolytic cell exceeds the upper alarm adaptive threshold of the decomposition voltage E or falls below the lower alarm adaptive threshold of the decomposition voltage E, it is determined that there is an abnormal decomposition voltage trend in the electrolytic cell and a blue alarm signal is issued.

[0036] When the resistance R of the electrolytic cell exceeds the upper alarm adaptive threshold of the resistance R or falls below the lower alarm adaptive threshold of the resistance R, it is determined that the resistance of the electrolytic cell has an abnormal trend and a blue alarm signal is issued.

[0037] This invention also provides a system for realizing online monitoring, evaluation, and fault location of the electrical parameters of the electrolytic cell group, including a voltage divider filter circuit, Analog-to-digital converter, slave microcomputer controller, DC current sensor, master microcomputer controller;

[0038] The voltage divider and filter circuit acquires the electrolytic cell voltage, reduces it to a preset range, filters out high-frequency interference signals, and transmits the data to... Analog-to-digital converter;

[0039] The analog-to-digital converter is used for electrical isolation in the high common-mode voltage environment of the electrolytic cell group and converts the analog signal collected by the voltage divider filter circuit into a high-speed unit data stream, and transmits the data to the slave microcomputer controller;

[0040] Collect several from the microcomputer controller The data from the analog-to-digital converter is digitally filtered to obtain the cell voltage of the electrolytic cell, and then output to the host microcomputer controller via RS485 bus and Modbus RTU communication protocol.

[0041] A DC current sensor, mounted on the positive bus, collects the series currents of the electrolytic cell, outputs a 4-20mA analog signal, and transmits it to the host microcomputer controller.

[0042] Based on the received data, the host microcomputer controller performs parameter calculation, fault assessment, and fault location in the online monitoring, evaluation, and fault location method for electrical parameters of the electrolytic cell group.

[0043] This invention discloses a method and system for online monitoring, evaluation and fault location of electrical parameters of an electrolytic cell group, which realizes early, accurate and intelligent anomaly detection and fault diagnosis and location of the electrolytic cell group, and achieves optimized control of the electrolysis process through communication with DCS. Attached Figure Description

[0044] Figure 1 This is a schematic flowchart of the method of the present invention;

[0045] Figure 2 This is a schematic diagram of the system structure of the present invention;

[0046] Figure 3 This is a schematic diagram of the connection structure of a series of electrolytic cells in an embodiment of the present invention. Detailed Implementation

[0047] This invention provides a method for online monitoring, evaluation, and fault location of electrical parameters of an electrolytic cell group, the flowchart of which is shown below. Figure 1 As shown, it includes the following steps:

[0048] S1. Real-time data acquisition and preprocessing of the electrolytic cell to obtain a real-time parameter dataset;

[0049] In step S1, the real-time data includes the series current of the electrolytic cell, the voltage of each electrolytic cell, and the corresponding electrolytic cell number;

[0050] Step S1 is as follows:

[0051] The preset time window length and calculation period are used to collect the series current I of the electrolytic cells and the voltage of each electrolytic cell. , where i is the electrolytic cell number;

[0052] Using the least squares method, the VI electrolysis curves of each electrolytic cell are generated in real time through linear fitting, and expressed by the following formula: ;

[0053] Based on the electrolysis curve, determine the intersection point of the electrolysis curve and the voltage coordinate axis. and the slope of the electrolysis curve ;

[0054] Calculate the voltage residual sequence for each electrolytic cell; the voltage residual is the difference between the cell voltage collected in real time and the cell voltage predicted by the currently fitted electrolysis curve model, calculated using the following formula: Where V is the real-time collected electrolytic cell voltage; I is the real-time collected electrolytic cell current; R is the resistance; E is the decomposition voltage; and e is the electrolytic cell voltage residual.

[0055] S2. Based on the real-time parameter dataset, set a fixed hard threshold and an adaptive threshold;

[0056] In step S2, the fixed hard threshold includes a fixed hard threshold for alarming above cell voltage and a fixed hard threshold for alarming below cell voltage; the fixed hard threshold is based on the highest operating cell voltage of the electrolytic cell. With minimum operating tank voltage The calculation is performed using the following formula: ; ;in, A fixed hard threshold is set for the alarm on the slot voltage; A fixed hard threshold is set for alarms under slot voltage.

[0057] The adaptive thresholds include adaptive thresholds for residual alarms (both upward and downward), voltage alarms (both upward and downward), resistance alarms (both upward and downward), and resistance alarms (both downward and upward). Setting these adaptive thresholds includes the following steps:

[0058] Set the data acquisition time window length and update cycle for calculating the adaptive threshold;

[0059] Based on the real-time parameter dataset obtained in step S1, obtain the data sequence of residual e within the time window. Decompose the data sequence of voltage E Data sequence with resistor R ;

[0060] The data sequence for calculating residual e moving average Use the following formula to calculate: Where n is the total number of data points in the data sequence; Let j be the j-th data point in the data sequence containing the residual e;

[0061] Calculate the data sequence of the decomposed voltage E moving average Use the following formula to calculate: Where n is the total number of data points in the data sequence; This refers to the j-th data point in the data sequence for decomposing voltage E.

[0062] Data sequence for calculating resistance R moving average Use the following formula to calculate: Where n is the total number of data points in the data sequence; This is the j-th data point in the data sequence for resistor R;

[0063] The data sequence for calculating residual e Moving standard deviation Use the following formula to calculate: ;

[0064] The adaptive threshold for alarm on residuals is calculated using the following formula. : ;in, This is the residual sensitivity coefficient;

[0065] The adaptive threshold for alarm under residuals is calculated using the following formula. : ;

[0066] Calculate the data sequence of the decomposed voltage E Moving standard deviation Use the following formula to calculate: ;

[0067] The upper alarm adaptive threshold of the decomposition voltage E is calculated using the following formula. : ;in, To decompose the voltage sensitivity coefficient;

[0068] The lower alarm adaptive threshold of the decomposition voltage E is calculated using the following formula. : ;

[0069] Data sequence for calculating resistance R Moving standard deviation Use the following formula to calculate: ;

[0070] Calculate the adaptive alarm threshold on resistor R using the following formula. : ;in, This is the resistance sensitivity coefficient;

[0071] Calculate the adaptive alarm threshold under resistance R using the following formula. : ;

[0072] The adaptive threshold updates automatically according to the set update cycle.

[0073] S3. Perform multi-dimensional fault diagnosis and location based on fixed hard threshold and adaptive threshold.

[0074] Step S3 is as follows:

[0075] When the cell voltage of the electrolytic cell exceeds the set fixed hard threshold range, it is determined that the electrolytic cell is faulty and a red emergency audible and visual alarm signal is issued.

[0076] When the residual voltage of the electrolytic cell exceeds the upper residual alarm adaptive threshold or falls below the lower residual alarm adaptive threshold, it is determined that the electrolytic cell is abnormal and a yellow warning signal is issued.

[0077] When the decomposition voltage E of the electrolytic cell exceeds the upper alarm adaptive threshold of the decomposition voltage E or falls below the lower alarm adaptive threshold of the decomposition voltage E, it is determined that there is an abnormal decomposition voltage trend in the electrolytic cell and a blue alarm signal is issued.

[0078] When the resistance R of the electrolytic cell exceeds the upper alarm adaptive threshold of the resistance R or falls below the lower alarm adaptive threshold of the resistance R, it is determined that the resistance of the electrolytic cell has an abnormal trend and a blue alarm signal is issued.

[0079] This invention also provides a system for realizing online monitoring, evaluation, and fault location of the electrical parameters of the electrolytic cell group, the structural schematic diagram of which is shown below. Figure 2 As shown, it includes a voltage divider filter circuit, Analog-to-digital converter, slave microcomputer controller, DC current sensor, master microcomputer controller;

[0080] The voltage divider and filter circuit acquires the electrolytic cell voltage, reduces it to a preset range, filters out high-frequency interference signals, and transmits the data to... Analog-to-digital converter;

[0081] The analog-to-digital converter is used for electrical isolation in the high common-mode voltage environment of the electrolytic cell group and converts the analog signal collected by the voltage divider filter circuit into a high-speed unit data stream, and transmits the data to the slave microcomputer controller;

[0082] Collect several from the microcomputer controller The data from the analog-to-digital converter is digitally filtered to obtain the cell voltage of the electrolytic cell, and then output to the host microcomputer controller via RS485 bus and Modbus RTU communication protocol.

[0083] A DC current sensor, mounted on the positive bus, collects the series currents of the electrolytic cell, outputs a 4-20mA analog signal, and transmits it to the host microcomputer controller.

[0084] Based on the received data, the host microcomputer controller performs parameter calculation, fault assessment, and fault location in the online monitoring, evaluation, and fault location method for electrical parameters of the electrolytic cell group.

[0085] The method of the present invention will be further described below with reference to an embodiment:

[0086] like Figure 3 The diagram shows an electrolytic zinc production line with an annual capacity of 100,000 tons. The DC series voltage ranges from 260V to 390V, and the series current ranges from 110 to 200kA. There are 100 electrolytic cells arranged in two rows of 50 cells each. The first row of cells is connected to the positive terminal of the power supply, and the second row is connected to the negative terminal. The two rows are connected by copper busbars. Conductive plates are installed on both sides of the electrolytic cells. The anode plates inside the cells are connected to the positive terminals of the conductive plates, and the cathode plates are connected to the negative terminals. The anode and cathode plates within the same cell are connected in parallel.

[0087] The cell voltage uses a fixed hard threshold plus a residual self-adaptive threshold. The fixed hard threshold is obtained by multiplying the highest and lowest operating voltages of the electrolytic cell by a reliability coefficient. The residual self-adaptive threshold is dynamically set using the moving average and moving standard deviation of the residuals. The residuals are used for anomaly monitoring, and their threshold update cycle is on the order of minutes. For example, an update cycle of 5 minutes can be selected.

[0088] The electrolytic cell decomposition voltage E and resistance R employ self-adaptive thresholds. Based on a linearly fitted electrolytic cell electrolysis curve model, the E and R data sequences are obtained, and the moving average and moving standard deviation of E and R are calculated to dynamically set the self-adaptive thresholds. As a trend monitoring mechanism, the threshold update cycle is on the order of tens of minutes; for example, an update cycle of 10 minutes can be selected.

[0089] When the cell voltage of the electrolytic cell exceeds the set fixed hard threshold range, it is determined that the electrolytic cell is faulty and a red emergency audible and visual alarm signal is issued.

[0090] When the residual voltage of the electrolytic cell exceeds the upper residual alarm adaptive threshold or falls below the lower residual alarm adaptive threshold, it is determined that the electrolytic cell is abnormal and a yellow warning signal is issued.

[0091] When the decomposition voltage E of the electrolytic cell exceeds the upper alarm adaptive threshold of the decomposition voltage E or falls below the lower alarm adaptive threshold of the decomposition voltage E, it is determined that there is an abnormal decomposition voltage trend in the electrolytic cell and a blue alarm signal is issued.

[0092] When the resistance R of the electrolytic cell exceeds the upper alarm adaptive threshold of the resistance R or falls below the lower alarm adaptive threshold of the resistance R, it is determined that the resistance of the electrolytic cell has an abnormal trend and a blue alarm signal is issued.

Claims

1. A method for online monitoring, evaluation, and fault location of electrical parameters of an electrolytic cell group, characterized in that, Includes the following steps: S1. Real-time data acquisition and preprocessing of the electrolytic cell to obtain a real-time parameter dataset; S2. Based on the real-time parameter dataset, set a fixed hard threshold and an adaptive threshold; S3. Perform multi-dimensional fault diagnosis and location based on fixed hard threshold and adaptive threshold.

2. The method for online monitoring, evaluation, and fault location of electrical parameters of an electrolytic cell group according to claim 1, characterized in that, In step S1, the real-time data includes the series current of the electrolytic cell, the voltage of each electrolytic cell, and the corresponding electrolytic cell number.

3. The method for online monitoring, evaluation, and fault location of electrical parameters of an electrolytic cell group according to claim 1, characterized in that, Step S1 is as follows: The preset time window length and calculation period are used to collect the series current I of the electrolytic cells and the voltage of each electrolytic cell. , where i is the electrolytic cell number; Using the least squares method, the VI electrolysis curves of each electrolytic cell are generated in real time through linear fitting, and expressed by the following formula: ; Based on the electrolysis curve, determine the intersection point of the electrolysis curve and the voltage coordinate axis. and the slope of the electrolysis curve ; Calculate the voltage residual sequence for each electrolytic cell; the voltage residual is the difference between the cell voltage collected in real time and the cell voltage predicted by the currently fitted electrolysis curve model, calculated using the following formula: Where V is the real-time collected electrolytic cell voltage; I is the real-time collected electrolytic cell current; R is the resistance; E is the decomposition voltage; and e is the electrolytic cell voltage residual.

4. The method for online monitoring, evaluation, and fault location of electrical parameters of an electrolytic cell group according to claim 1, characterized in that, In step S2, the fixed hard threshold includes a fixed hard threshold for alarming above cell voltage and a fixed hard threshold for alarming below cell voltage; the fixed hard threshold is based on the highest operating cell voltage of the electrolytic cell. With minimum operating tank voltage The calculation is performed using the following formula: ; ;in, A fixed hard threshold is set for the alarm on the slot voltage; A fixed hard threshold is set for alarms under slot voltage.

5. The method for online monitoring, evaluation, and fault location of electrical parameters of an electrolytic cell group according to claim 1, characterized in that, In step S2, the adaptive thresholds include an adaptive threshold for residual alarms (upward and downward), an adaptive threshold for residual alarms (downward), an adaptive threshold for voltage alarms (upward and downward), an adaptive threshold for resistance alarms (upward and downward), and an adaptive threshold for resistance alarms (downward). Setting these adaptive thresholds includes the following steps: Set the data acquisition time window length and update cycle for calculating the adaptive threshold; Based on the real-time parameter dataset obtained in step S1, obtain the data sequence of residual e within the time window. Decompose the data sequence of voltage E Data sequence with resistor R ; The data sequence for calculating residual e moving average Use the following formula to calculate: Where n is the total number of data points in the data sequence; Let j be the j-th data point in the data sequence containing the residual e; Calculate the data sequence of the decomposed voltage E moving average Use the following formula to calculate: Where n is the total number of data points in the data sequence; This refers to the j-th data point in the data sequence for decomposing voltage E. Data sequence for calculating resistance R moving average Use the following formula to calculate: Where n is the total number of data points in the data sequence; This is the j-th data point in the data sequence for resistor R; The data sequence for calculating residual e Moving standard deviation Use the following formula to calculate: ; The adaptive threshold for alarm on residuals is calculated using the following formula. : ;in, This is the residual sensitivity coefficient; The adaptive threshold for alarm under residuals is calculated using the following formula. : ; Calculate the data sequence of the decomposed voltage E Moving standard deviation Use the following formula to calculate: ; The upper alarm adaptive threshold of the decomposition voltage E is calculated using the following formula. : ;in, To decompose the voltage sensitivity coefficient; The lower alarm adaptive threshold of the decomposition voltage E is calculated using the following formula. : ; Data sequence for calculating resistance R Moving standard deviation Use the following formula to calculate: ; Calculate the adaptive alarm threshold on resistor R using the following formula. : ;in, This is the resistance sensitivity coefficient; Calculate the adaptive alarm threshold under resistance R using the following formula. : ; The adaptive threshold updates automatically according to the set update cycle.

6. The method for online monitoring, evaluation, and fault location of electrical parameters of an electrolytic cell group according to claim 1, characterized in that, Step S3 is as follows: When the cell voltage of the electrolytic cell exceeds the set fixed hard threshold range, it is determined that the electrolytic cell is faulty and a red emergency audible and visual alarm signal is issued. When the residual voltage of the electrolytic cell exceeds the upper residual alarm adaptive threshold or falls below the lower residual alarm adaptive threshold, it is determined that the electrolytic cell is abnormal and a yellow warning signal is issued. When the decomposition voltage E of the electrolytic cell exceeds the upper alarm adaptive threshold of the decomposition voltage E or falls below the lower alarm adaptive threshold of the decomposition voltage E, it is determined that there is an abnormal decomposition voltage trend in the electrolytic cell and a blue alarm signal is issued. When the resistance R of the electrolytic cell exceeds the upper alarm adaptive threshold of the resistance R or falls below the lower alarm adaptive threshold of the resistance R, it is determined that the resistance of the electrolytic cell has an abnormal trend and a blue alarm signal is issued.

7. A system for implementing the online monitoring, evaluation, and fault location method for electrical parameters of an electrolytic cell group as described in any one of claims 1 to 6, characterized in that, Including voltage divider filter circuit, Analog-to-digital converter, slave microcomputer controller, DC current sensor, master microcomputer controller; The voltage divider and filter circuit acquires the electrolytic cell voltage, reduces it to a preset range, filters out high-frequency interference signals, and transmits the data to... Analog-to-digital converter; The analog-to-digital converter is used for electrical isolation in the high common-mode voltage environment of the electrolytic cell group and converts the analog signal collected by the voltage divider filter circuit into a high-speed unit data stream, and transmits the data to the slave microcomputer controller; Collect several from the microcomputer controller The data from the analog-to-digital converter is digitally filtered to obtain the cell voltage of the electrolytic cell, and then output to the host microcomputer controller via RS485 bus and Modbus RTU communication protocol. A DC current sensor, mounted on the positive bus, collects the series currents of the electrolytic cell, outputs a 4-20mA analog signal, and transmits it to the host microcomputer controller. Based on the received data, the host microcomputer controller performs parameter calculation, fault assessment, and fault location in the online monitoring, evaluation, and fault location method for electrical parameters of the electrolytic cell group.

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