Aluminum oxide dissolution control system
By adding diodes and optocouplers to the alumina leaching control system, accurate detection of phase loss and phase sequence of three-phase power supply was achieved, solving the equipment damage problem caused by phase loss of frequency converter and improving production efficiency and equipment stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-21
- Publication Date
- 2026-03-20
AI Technical Summary
In alumina production, the operation of frequency converters with a single phase loss can lead to damage to devices and machines. At the same time, it is necessary to determine the consistency of phase sequence during process switching to avoid equipment damage. Existing technologies are difficult to solve this problem effectively.
In the alumina leaching control system, by adding diodes and two optocouplers, an asymmetric method is used to identify phase loss in the three-phase power supply and detect the phase sequence. The phase loss judgment module and the phase sequence detection module are used to determine the phase loss and phase sequence.
It enables accurate identification of phase loss and phase sequence detection in three-phase power supply, avoids inverter overvoltage alarms, improves production efficiency, meets heat treatment process requirements, and ensures stable equipment operation.
Smart Images
Figure CN224020163U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of alumina, especially relates to a alumina dissolution control system. BACKGROUND
[0002] Alumina production mainly adopts the Bayer method, wherein the alumina in bauxite is dissolved by high-temperature and high-pressure lye in the dissolution link, and the efficiency directly affects the overall energy consumption (accounting for about 30%-40%) and product quality. Taking China as an example, the proportion of domestic diaspore is more than 80%, which needs to be dissolved at a high temperature of 260-280 DEG C, and the traditional process relies on a large amount of lime (dry ore amount 10%-12%) to eliminate titanium mineral retardation, but causes the red mud amount to increase by more than 30%.
[0003] Among them, the frequency converter is the core part of the alumina dissolution control system. In the industry, the open-phase operation of the frequency converter will cause damage to the device and the machine. In addition, in some special fields, the frequency conversion switching needs to be carried out, which requires the frequency converter to judge the consistency of the input phase sequence to avoid damage to the equipment. UTILITY MODEL CONTENTS
[0004] In order to solve the above problems, the utility model provides an alumina dissolution control system, which aims to ensure that the open-phase operation of the frequency converter will cause damage to the device and the machine.
[0005] In order to achieve the above purpose, the utility model provides the following technical scheme:
[0006] The utility model provides a alumina dissolution control system, including motor, frequency converter, control circuit, frequency converter is connected in the front end of motor, relief resistance is connected in the pressure relief joint of frequency converter, control circuit includes first current -limiting resistance, second current -limiting resistance and third current -limiting resistance connected to first phase line, second phase line and third phase line respectively, first optocoupler, second optocoupler, first diode, second diode, sampling resistance and open -phase judging module, wherein: the first diode is connected in the rear end of first current -limiting resistance in positive direction, the second diode is connected in the rear end of second current -limiting resistance in reverse direction, and the negative pole of first diode is connected to the positive pole of second diode;The first end of sampling resistance is connected to the negative pole of second diode, and the second end is connected to the rear end of third current -limiting resistance;The primary side of first optocoupler and second optocoupler is connected in opposite polarity to the two ends of sampling resistance respectively;The open -phase judging module confirms the phase line of open -phase according to the secondary side output signal of first optocoupler and second optocoupler;
[0007] The phase deficiency judging module confirms that the phase line is normal when the secondary sides of the first optocoupler and the second optocoupler output pulse waves, confirms that the first phase line is deficient in phase when the secondary side of the first optocoupler outputs a high level and the secondary side of the second optocoupler outputs a pulse wave, confirms that the second phase line is deficient in phase when the secondary side of the first optocoupler outputs a pulse wave and the secondary side of the second optocoupler outputs a high level, and confirms that the third phase line is deficient in phase when the secondary sides of the first optocoupler and the second optocoupler output high levels.
[0008] The inspection device further comprises a control circuit connected to the secondary sides of the first optocoupler and the second optocoupler and judging the phase sequence of the first phase line, the second phase line and the third phase line according to the time sequence of the output pulses of the first optocoupler and the second optocoupler.
[0009] When the output pulse of the first optocoupler leads the output pulse of the second optocoupler, the control circuit confirms that the currents of the first phase line, the second phase line and the third phase line are sequentially different by 120°, and when the output pulse of the first optocoupler lags behind the output pulse of the second optocoupler, the control circuit confirms that the currents of the first phase line, the third phase line and the second phase line are sequentially different by 120°.
[0010] The first end of the sampling resistor is connected to the positive pole of the primary side of the first optocoupler via a forwardly connected third diode, and the negative pole of the primary side of the second optocoupler is connected to the first end of the sampling resistor via a forwardly connected fourth diode.
[0011] Compared with the prior art, the utility model has the beneficial effects that:
[0012] The alumina dissolution control system of the utility model realizes the identification of the phase line of the deficient phase in the three-phase power supply in an asymmetric mode by adding a diode and two optocouplers on the basis of the original phase deficiency inspection device.
[0013] The OLED display circuit is stable in performance, simple in structure and convenient for users to use.
[0014] When the load weight exceeds 1500 Kg, the frequency converter does not overpressure alarm and stop outputting in either the rising state or the falling state, the heat treatment weight is improved, the production efficiency is improved and the heat treatment process requirements are met. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 is the alumina dissolution control system drawing of the utility model.
[0016] Figure 2 is the OLED display circuit principle diagram of the utility model. DETAILED DESCRIPTION
[0017] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the utility model.
[0018] As Figure 1 shown, it is a schematic diagram of the phase loss checking device embodiment of the utility model, which can be connected to a three-phase power supply and used for detecting a phase loss line of the three-phase power supply. The phase loss checking device in the embodiment comprises a first current-limiting resistor R1, a second current-limiting resistor R2 and a third current-limiting resistor R3 connected to a first phase line, a second phase line and a third phase line respectively, and the checking device further comprises a first optocoupler U1, a second optocoupler U2, a first diode D1, a second diode D2, a sampling resistor R4 and a phase loss judgment module. The above-mentioned first diode D1 is connected in forward direction at the rear end of the first current-limiting resistor R1 (i.e. the anode of the first diode D1 is connected at the rear end of the first current-limiting resistor R1), the second diode D2 is connected in reverse direction at the rear end of the second current-limiting resistor R2 (i.e. the cathode of the second diode D2 is connected at the rear end of the second current-limiting resistor R2), and the cathode of the first diode D1 is connected to the anode of the second diode D2; the first end of the sampling resistor R4 is connected to the cathode of the second diode D2, and the second end is connected to the rear end of the third current-limiting resistor R3; the primary sides of the first optocoupler U1 and the second optocoupler U2 are connected in polarity opposite ways at the two ends of the sampling resistor R4 (for example, the anode of the primary side of the first optocoupler U1 is connected to the first end of the sampling resistor R4, and the cathode is connected to the second end of the sampling resistor R4, and the anode of the primary side of the second optocoupler U2 is connected to the second end of the sampling resistor R4, and the cathode is connected to the first end of the sampling resistor R4); the phase line of the phase loss is confirmed by the phase loss judgment module according to the secondary side output signals V1 and V2 of the first optocoupler U1 and the second optocoupler U2.
[0019] The alumina dissolution control system of the utility model realizes the identification of the phase line of the phase loss in the three-phase power supply in an asymmetric way by adding a diode and two optocouplers on the basis of the original phase loss checking device. And the phase loss checking device of the utility model can also be used for realizing the phase sequence detection of the three-phase power supply.
[0020] In the above-mentioned phase loss checking device, the expressions of the voltages Va, Vb and Vc on the first phase line, the second phase line and the third phase line are as follows:
[0021] V a =V l sinθ;
[0022] V b =V l sin(θ+120°);
[0023] Vc = Vlsin(0 - 120°);
[0024] where V1 is the maximum voltage.
[0025] According to the circuit theory, Figure 1 In the absence of the second diode D2, the voltage on the sampling resistor R4 is equal to the sum of the voltage on the sampling resistor R4 of the first phase line, the second phase line and the third phase line voltage Va, Vb, Vc respectively:
[0026]
[0027] The component of the first phase line on the sampling resistor R4 is:
[0028]
[0029] The component of the second phase line on the sampling resistor R4 is:
[0030]
[0031] The component of the third phase line on the sampling resistor R4 is:
[0032]
[0033] In the case of R1 = R2 = R3 = R (i.e. the resistance of the first current limiting resistor R1, the second current limiting resistor R2 and the third current limiting resistor R3 are all R), the above expression can be simplified as:
[0034]
[0035] The component of the first phase line on the sampling resistor R4 is:
[0036]
[0037] The component of the second phase line on the sampling resistor R4 is:
[0038]
[0039] The component of the third phase line on the sampling resistor R4 is:
[0040]
[0041] Thus, the voltage applied to the sampling resistor R4 is:
[0042]
[0043] After adding the second diode D2, the voltage on the sampling resistor R4 changes, as follows:
[0044] When Va1>V b1>V c1, the voltage on the sampling resistor R4 is still the superposition of the first phase line, the second phase line and the third phase line voltage:
[0045]
[0046] When V b1>V a1>V 1c, the voltage on the sampling resistor R4 is the superposition of the first phase line and the third phase line voltage:
[0047]
[0048] When V b1>V c1>V a1, the voltage on the sampling resistor R4 is zero, that is, VR4=0;
[0049] When V c1>V b1>V a1, the voltage on the sampling resistor R4 is still the superposition of the second phase line and the third phase line voltage:
[0050]
[0051] When V c1>V a1>V b1, the voltage on the sampling resistor R4 is still the superposition of the second phase line and the third phase line voltage:
[0052]
[0053] When Va1>V c1>V b1, the voltage on the sampling resistor R4 is still the superposition of the first phase line, the second phase line and the third phase line voltage:
[0054]
[0055] From the above analysis, it can be seen that when the second diode D2 is in the circuit, the voltage across the sampling resistor R4 has three situations, that is: Or VR4=0 .
[0056] Correspondingly, Figure 1 In the phase absence checking device shown, the first optocoupler U1 and the second optocoupler U2 detect the positive voltage and the negative voltage of the sampling resistor R4 respectively, when the voltage on the sampling resistor R4 is positive, the first optocoupler U1 is turned on, and when the voltage on the sampling resistor R4 is negative, the second optocoupler U2 is turned on.
[0057] Attached Figure 1The utility model discloses an alumina dissolution control system diagram, in drawing, 1 is control switch, 2 is frequency converter, 3 is motor, R1 and R2 are pressure relief resistance, can know from the drawing, the utility model discloses an alumina dissolution control system includes the motor of power 5.5KW, the frequency converter of model number AMB-G7-7R5T3, the frequency converter is connected at the front end of motor, and the pressure relief resistance of 60Ω / 1KW is connected to frequency converter pressure relief joint, the frequency for using when rising is 35Hz, and the frequency for using when falling is 120Hz, its characterized in that, at pressure relief resistance R1 place, parallel connection again the pressure relief resistance R2 of 60Ω / 1KW, as mentioned above, when the load weight exceeds 1500 Kg, whether it is the rising state or the falling state, all will appear the phenomenon that frequency converter overvoltage alarm and stop output, after observation, found that after each shutdown, the surface temperature of pressure relief resistance R1 is obviously raised, shows that pressure relief resistance R1 resistance is higher and the power is smaller, makes its pressure relief and heat dissipation are not timely, causes frequency converter overheat protection, according to the utility model discloses an alumina dissolution control system at pressure relief resistance R1 place parallel connection again the pressure relief resistance R2 of 60Ω / 1KW, solved above-mentioned problem, even if the load weight exceeds 1500 Kg, whether it is the rising state or the falling state, all will not appear the phenomenon that frequency converter overvoltage alarm and stop output, effectively improved heat treatment weight, effectively improved production efficiency, and satisfy the heat treatment process requirement.
[0058] By, the combination of the secondary side output voltage V1 of the first optocoupler U1 and the secondary side output voltage V2 of the second optocoupler U2 can not only judge the open-phase fault, but also judge which phase is open-phase, and theoretically, the open-phase can be detected within one cycle, that is, the open-phase judgment module confirms that the phase line is normal when the secondary sides of the first optocoupler U1 and the second optocoupler U2 output pulse waves, confirms that the first phase line is open-phase when the secondary side of the first optocoupler U1 outputs a high level and the secondary side of the second optocoupler U2 outputs a pulse wave, confirms that the second phase line is open-phase when the secondary side of the first optocoupler U1 outputs a pulse wave and the secondary side of the second optocoupler U2 outputs a high level, and confirms that the third phase line is open-phase when the secondary sides of the first optocoupler U1 and the second optocoupler U2 output high levels, that is:
[0059] V1 V2 State 50HZ pulse 50HZ pulse Normal High level 50HZ pulse First phase line open 50HZ pulse High level Second phase line open High level High level Third phase line open
[0060] In addition, the above-mentioned open-phase checking device can further include a phase sequence detection module, and the phase sequence detection is realized through the phase sequence detection module. The phase sequence detection module is connected to the secondary sides of the first optocoupler U1 and the second optocoupler U2, and judges the phase sequence of the first phase line, the second phase line and the third phase line according to the time sequence of the output pulses of the first optocoupler U1 and the second optocoupler U2.
[0061] Specifically, when the output pulse of the first optocoupler U1 leads the output pulse of the second optocoupler U2, the phase sequence detection module confirms that the currents of the first phase line, the second phase line and the third phase line are sequentially 120° apart; when the output pulse of the first optocoupler U1 lags behind the output pulse of the second optocoupler U1 (as shown in the figure), the phase sequence detection module confirms that the currents of the first phase line, the third phase line and the second phase line are sequentially 120° apart. Figure 1 To improve the safety of detection, the third diode D3 and the fourth diode D4 can be added in the above phase deficiency inspection device, that is, the first end of the sampling resistor R4 is connected to the positive pole of the primary side of the first optocoupler U1 through the third diode D3 connected in forward direction; the negative pole of the primary side of the second optocoupler U2 is connected to the first end of the sampling resistor R4 through the fourth diode D4 connected in forward direction.
[0062] Figure 2 The OLED display circuit principle diagram of the utility model is shown in the figure, the OLED display circuit includes operating register and data register drive OLED display character. Figure 2 The utility model OLED display circuit performance is stable, constitutes simply, it is convenient for user to use.
[0063] Although the utility model has been explained in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features, any modification, equivalent replacement, improvement etc. within the spirit and principle of the utility model should be included in the protection scope of the utility model.
Claims
1. An alumina leaching control system, characterized in that, The system includes a motor, a frequency converter, and a control circuit. The frequency converter is connected to the front end of the motor, and a pressure relief resistor is connected to the frequency converter's pressure relief connector. The control circuit includes a first current-limiting resistor, a second current-limiting resistor, and a third current-limiting resistor, respectively connected to the first phase line, the second phase line, and the third phase line; a first optocoupler, a second optocoupler, a first diode, a second diode, a sampling resistor, and a phase loss detection module. Specifically: the first diode is forward-biased and connected to the rear end of the first current-limiting resistor; the second diode is reverse-biased and connected to the rear end of the second current-limiting resistor; the negative terminal of the first diode is connected to the positive terminal of the second diode; the first end of the sampling resistor is connected to the negative terminal of the second diode, and the second end is connected to the rear end of the third current-limiting resistor; the primary windings of the first and second optocouplers are connected to the two ends of the sampling resistor with opposite polarities; the phase loss detection module identifies the missing phase line based on the output signals from the secondary windings of the first and second optocouplers. The phase loss detection module confirms that the phase line is normal when both the secondary sides of the first and second optocouplers output pulse waves; confirms that the first phase line is missing when the secondary side of the first optocoupler outputs a high level and the secondary side of the second optocoupler outputs a pulse wave; confirms that the second phase line is missing when the secondary side of the first optocoupler outputs a pulse wave and the secondary side of the second optocoupler outputs a high level; and confirms that the third phase line is missing when both the secondary sides of the first and second optocouplers output a high level.
2. The alumina leaching control system according to claim 1, characterized in that: The inverter model is AMB-G7-7R5T3; the voltage relief resistor is 60Ω / 1kW; the frequency used during rise is 35Hz; and the frequency used during fall is 120Hz.
3. The alumina leaching control system according to claim 1, characterized in that, It also includes an inspection device; the inspection device further includes a control circuit, which is connected to the secondary side of the first optocoupler and the second optocoupler, and determines the phase sequence of the first phase line, the second phase line and the third phase line according to the timing of the output pulses of the first optocoupler and the second optocoupler.
4. The alumina leaching control system according to claim 3, characterized in that: When the output pulse of the first optocoupler leads the output pulse of the second optocoupler, the control circuit confirms that the currents of the first phase line, the second phase line, and the third phase line are sequentially 120° apart; when the output pulse of the first optocoupler lags behind the output pulse of the second optocoupler, the control circuit confirms that the currents of the first phase line, the third phase line, and the second phase line are sequentially 120° apart.
5. The alumina leaching control system according to claim 1, characterized in that: The first terminal of the sampling resistor is connected to the positive terminal of the primary side of the first optocoupler via a forward-connected third diode; the negative terminal of the primary side of the second optocoupler is connected to the first terminal of the sampling resistor via a forward-connected fourth diode.
6. The alumina leaching control system according to claim 1, characterized in that, It also includes an OLED display circuit, which includes an operation register and a data register to drive the OLED to display characters.