Ground insulation fault detection equipment for cathode bus of aluminum electrolysis cell
By designing an aluminum electrolytic cell fault detection device including a sampling module, a switching module and a DC isolation module, the problem of difficulty in accurately positioning the fault point of the aluminum electrolytic cell to the ground in the prior art is solved, and the accurate positioning of the fault point is achieved and improve accuracy.
Patent Information
- Application Number
- CN202420341966.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-23
- Publication Date
- 2025-02-11
- Estimated Expiration
- 2034-02-23
AI Technical Summary
The existing zero-point drift detection method is difficult to accurately locate the fault point of the insulation of the aluminum electrolytic cell to the ground, especially when the fault impedance is not zero or the voltage fluctuates.
An aluminum electrolytic cell cathode busbar to ground insulation fault detection device is designed, including a sampling module, a switching module, a DC isolation module, a controller, a touch display screen and a DC power module. By measuring the voltage and impedance under normal circumstances, recording data, and comparing and computing in a fault state, determining the impedance and position of the fault point.
The fault point of the aluminum electrolytic cell is accurately positioned, which can still be effective when the fault impedance is not zero or voltage fluctuates, reducing errors and improving detection accuracy.
Smart Images
Figure CN222461648U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of electrolytic aluminum production, in particular to a device for detecting insulation faults of cathode busbars of aluminum electrolytic cells to the ground. Background Art
[0002] Aluminum electrolytic cells are essential production equipment in the aluminum electrolysis industry, and their operating status directly affects the production efficiency and economic benefits of aluminum electrolytic plants. However, due to insulation damage or artificial overlap, aluminum electrolytic cells are prone to ground insulation failure, which brings huge losses to enterprises.
[0003] For such a special DC system as the aluminum electrolysis plant, it is very necessary to detect and locate the fault point quickly and accurately, which can reduce many unnecessary losses.
[0004] The zero-point drift detection method is currently the most widely used detection method. This detection method performs voltage detection at both ends of the aluminum electrolysis cell production line, that is, at the point where the voltage of the aluminum electrolysis cell production line is the largest, and at the point where the potential on the cathode busbar of the aluminum electrolysis cell is zero relative to the earth voltage. When an aluminum electrolysis cell has an insulation failure to the ground, its zero point will shift accordingly. By measuring the voltage drift of the zero point and dividing it by the standard voltage of a single aluminum electrolysis cell, the location of the faulty aluminum electrolysis cell can be determined.
[0005] However, the short circuit of the electrolytic cell to the ground is sometimes not an absolute short circuit, and the impedance of the fault is not necessarily zero. Sometimes it may be several ohms or thousands of ohms. In addition, due to interference from external factors, the actual working voltage of each aluminum electrolytic cell may fluctuate. Therefore, the zero-point drift detection method cannot accurately locate the fault point. Summary of the invention
[0006] The purpose of the utility model is to solve the above problems and provide an aluminum electrolytic cell cathode busbar to ground insulation fault detection device, which can effectively and accurately detect the location of the fault point, and is still applicable when the aluminum electrolytic cell is grounded with resistance. The following solutions are adopted to achieve the above purpose:
[0007] A device for detecting insulation faults of cathode busbars of aluminum electrolysis cells to ground, comprising: a sampling module, a switching module, a DC isolation module, a controller, a touch display screen and a DC power supply module, wherein the sampling module and the DC isolation module are both connected in parallel between the cathode busbar of the aluminum electrolysis cell and grounding, and the switching module is connected in series on the cathode busbar of the aluminum electrolysis cell between the sampling module and the DC isolation module, the switching module is electrically connected to the input end of the DC isolation module, the output end of the DC isolation module is electrically connected to the input end of the controller, the controller is electrically connected to the touch display screen, the output end of the controller is electrically connected to the sampling module and the switching module, and the DC power supply module is electrically connected to the sampling module, the switching module, the DC isolation module, the controller and the touch display screen.
[0008] Furthermore, the sampling module internally comprises a plurality of sampling module resistors with different resistance values and sampling module relays respectively connected in series therewith, and the sampling module resistors and sampling module relays of the same group are connected in parallel between the cathode busbar of the aluminum electrolytic cell and the ground.
[0009] Furthermore, the switching module includes a plurality of switching module relays, each switching module relay is connected in parallel, each switching module relay is connected in series with the cathode busbar of the aluminum electrolysis cell, and each switching module relay is electrically connected to an input port of the DC isolation module.
[0010] Furthermore, the DC isolation module is a DC current and voltage transmitter, and its specification is ±600V / ±1500V to ±10V.
[0011] Furthermore, the controller is a device with logic operation function.
[0012] Furthermore, the output end of the controller is electrically connected to the sampling module relay and the switching module relay.
[0013] Detection principle:
[0014] The sampling module contains multiple sampling module resistors with different resistance values and sampling module relays connected in series with them. The sampling module resistors with different resistance values are switched according to the different aluminum electrolysis cell system voltages and the installation positions of the detection devices.
[0015] The switching module contains multiple switching module relays, each of which is electrically connected to an input port of the DC isolation module. It switches according to the voltage of the aluminum electrolysis cell system to switch the working state of the DC isolation module, so that the voltage signal output by the DC isolation module is more accurate.
[0016] In the whole aluminum electrolytic cell system, multiple groups of detection devices are arranged, and the multiple groups of detection devices are connected to the terminal by wired or wireless means. Among the multiple groups of detection devices, except for one group of detection devices as detection points, the other detection devices are sampling points. The sampling modules of the detection point detection devices are regularly connected to the aluminum electrolytic cell system circuit, and the sampling modules of the sampling point detection devices are open circuit.
[0017] According to the different voltages of the aluminum electrolytic cell system, the controller controls the switching module to work through the touch screen of the detection point, so that different input ports of the DC isolation module are connected to the circuit. When the sampling module is not connected to the circuit, the controller receives the normal system voltage signal of the detection point. When the sampling module is connected to the circuit, the controller receives the normal system voltage signal after the detection point is connected to the resistor. According to the Thevenin theorem, the controller can calculate the system impedance. When the system impedance calculated by the controller in a certain period of time is different from the previous data, it means that the aluminum electrolytic cell system has a fault at this time. The system impedance calculated this time is the system impedance at the time of the fault. The fault resistance of the fault point can be obtained by calculating the impedance and the system impedance at fault. The voltage at the fault point can be obtained by calculating the normal system impedance, the fault system impedance, the normal sampling voltage and the fault sampling voltage. The voltage at the fault point is subtracted from the voltage at other sampling points and the absolute value is taken. The sampling point with the smallest absolute value is the point closest to the fault point. The cell number of the aluminum electrolytic cell corresponding to the fault point can be calculated based on the standard voltage of a single aluminum electrolytic cell. Although the actual working voltage of the aluminum electrolytic cell will fluctuate under the influence of various factors, it does not affect the accurate positioning of the fault point because it is known which detection device is closest to the fault point.
[0018] Advantages of the utility model
[0019] (1) The utility model measures the voltage and impedance of the monitoring position of the electrolytic cell to the ground under normal conditions, records the data, and then monitors the voltage and impedance of the fault state. By comparing the measured data with historical data, the impedance of the short-circuit point, the position of the short-circuit point and other clear information can be obtained through calculation and analysis. Even if the short circuit of the aluminum electrolytic cell to the ground is sometimes not an absolute short circuit, and the impedance of the fault is not necessarily zero, the utility model can still accurately locate the fault point.
[0020] (2) After obtaining the voltage at the fault point, the utility model compares and analyzes it with the voltages of other sampling points, and can determine which sampling point is closest to the fault point. Then, the cell number of the aluminum reduction cell corresponding to the fault point is calculated based on the cell number of the aluminum reduction cell closest to the sampling point, thereby avoiding errors caused by fluctuations in the actual working voltage of the aluminum reduction cell under the influence of various factors, and making the location of the fault point more accurate. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 It is a structural schematic diagram of a device for detecting insulation failure of cathode busbar to ground of an aluminum electrolytic cell according to the utility model;
[0022] The meanings of the symbols in the figure are as follows:
[0023] 1-sampling module; 101-sampling module resistor; 102-sampling module relay; 2-switching module; 201-switching module relay; 3-DC isolation module; 4-controller; 5-touch display screen; 6-DC power supply module. DETAILED DESCRIPTION
[0024] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0025] A device for detecting insulation faults of cathode busbars of aluminum electrolysis cells to ground, comprising: a sampling module 1, a switching module 2, a DC isolation module 3, a controller 4, a touch display screen 5 and a DC power supply module 6, wherein the sampling module 1 and the DC isolation module 3 are both connected in parallel between the cathode busbar of the aluminum electrolysis cell and the ground, the switching module 2 is connected in series on the cathode busbar of the aluminum electrolysis cell between the sampling module 1 and the DC isolation module 3, the switching module 2 is electrically connected to the input end of the DC isolation module 3, the output end of the DC isolation module 3 is electrically connected to the input end of the controller 4, the controller 4 is electrically connected to the touch display screen 5, the output end of the controller 4 is electrically connected to the sampling module 1 and the switching module 2, and the DC power supply module 6 is electrically connected to the sampling module 1, the switching module 2, the DC isolation module 3, the controller 4 and the touch display screen 5.
[0026] Preferably, the sampling module 1 includes a plurality of sampling module resistors 101 with different resistance values and sampling module relays 102 respectively connected in series therewith, and the sampling module resistors 101 and sampling module relays 102 of the same group are connected in parallel between the cathode busbar of the aluminum electrolysis cell and the ground.
[0027] Preferably, the resistance of the sampling module resistor 101 needs to satisfy the requirement that the voltage change of the aluminum electrolytic cell at the sampling point before and after the parallel resistor is connected is not greater than 2 times the standard operating voltage of a single aluminum electrolytic cell.
[0028] Preferably, the switching module 2 includes multiple switching module relays 201, each switching module relay 201 is connected in parallel, each switching module relay 201 is connected in series with the cathode bus of the aluminum electrolysis cell, and each switching module relay 201 is electrically connected to an input port of the DC isolation module 3.
[0029] Preferably, the DC isolation module 3 is a DC current and voltage transmitter, and its specification is ±600V / ±1500V to ±10V.
[0030] Preferably, the controller 4 is a PLC controller integrated with a wireless communication module.
[0031] Preferably, the output end of the controller 4 is electrically connected to the sampling module relay 102 and the switching module relay 201 .
Claims
1. A device for detecting insulation faults of cathode busbars of aluminum electrolysis cells to the ground, characterized in that: include: A sampling module (1), a switching module (2), a DC isolation module (3), a controller (4), a touch display screen (5) and a DC power supply module (6), wherein the sampling module (1) and the DC isolation module (3) are both connected in parallel between the cathode busbar of the aluminum electrolysis cell and the ground, and the switching module (2) is connected in series on the cathode busbar of the aluminum electrolysis cell between the sampling module (1) and the DC isolation module (3), the switching module (2) is electrically connected to the input end of the DC isolation module (3), the output end of the DC isolation module (3) is electrically connected to the input end of the controller (4), the controller (4) is electrically connected to the touch display screen (5), the output end of the controller (4) is electrically connected to the sampling module (1) and the switching module (2), and the DC power supply module (6) is electrically connected to the sampling module (1), the switching module (2), the DC isolation module (3), the controller (4) and the touch display screen (5).
2. The aluminum electrolysis cell cathode busbar to ground insulation fault detection device according to claim 1, characterized in that: The sampling module (1) internally comprises a plurality of sampling module resistors (101) with different resistance values and sampling module relays (102) respectively connected in series therewith; the sampling module resistors (101) and sampling module relays (102) of the same group are connected in parallel between the cathode busbar of the aluminum electrolysis cell and the ground.
3. The aluminum electrolysis cell cathode busbar to ground insulation fault detection device according to claim 1, characterized in that: The switching module (2) comprises a plurality of switching module relays (201) therein, each switching module relay (201) is connected in parallel, each switching module relay (201) is connected in series with the cathode busbar of the aluminum electrolysis cell, and each switching module relay (201) is electrically connected to an input port of the DC isolation module (3).
4. The aluminum electrolysis cell cathode busbar to ground insulation fault detection device according to claim 1, characterized in that: The DC isolation module (3) is a DC current and voltage transmitter, and its specification is ±600V / ±1500V to ±10V.
5. The aluminum electrolysis cell cathode busbar to ground insulation fault detection device according to claim 1, characterized in that: The controller (4) is a device with logic operation function.
6. The aluminum electrolysis cell cathode busbar to ground insulation fault detection device according to any one of claims 1 to 5, characterized in that: The output end of the controller (4) is electrically connected to the sampling module relay (102) and the switching module relay (201).