Control method, device and equipment for continuous casting equipment

Abstract

The invention discloses a control method, device and equipment of continuous casting equipment, the continuous casting equipment comprises a tundish, a negative electrode assembly and a power supply, the tundish comprises a stopper rod and a submersed nozzle, the negative electrode assembly is fixedly arranged in the tundish and is in contact with molten steel in the tundish, the positive electrode of the power supply is connected with the stopper rod and the submersed nozzle, and the negative electrode of the power supply is in contact with the submersed nozzle. The method comprises the steps that when the continuous casting equipment conducts casting, the current height of a stopper rod is obtained, and the higher the current height is, the higher the blocking risk of the submersed nozzle is; based on the current height, a current duty cycle of the power supply is controlled. According to the invention, the technical problem that inclusions are easily attached to the submersed nozzle and the stopper rod of the tundish is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of continuous casting, and in particular relates to a control method, device and equipment for continuous casting equipment. Background Art

[0002] The submerged nozzle is the molten steel outlet of the tundish, and the molten steel flowing out of the submerged nozzle enters the crystallizer. The stopper rod is a refractory rod installed in the tundish to control the opening and closing of the submerged nozzle and the flow of molten steel by lifting and displacement.

[0003] There are many inclusions in the molten steel in the tundish. If the inclusions are attached to the submerged nozzle of the tundish, the submerged nozzle may be blocked. Then, when the molten steel enters the crystallizer from the submerged nozzle, it may cause the molten steel to flow asymmetrically in the crystallizer, and the liquid level fluctuation of the molten steel on the unblocked side of the crystallizer will increase significantly, causing the protective slag on the surface of the molten steel in the crystallizer to be drawn into the molten steel, reducing the quality of the ingot. If the inclusions are attached to the stopper rod of the tundish, as the number of attached inclusions increases, the inclusions on the stopper rod may fall off. The fallen inclusions enter the crystallizer from the submerged nozzle, which will also cause the liquid level fluctuation of the molten steel in the crystallizer to increase significantly, causing the protective slag on the surface of the molten steel in the crystallizer to be drawn into the molten steel, reducing the quality of the ingot. Therefore, it is a technical problem that inclusions are easily attached to the submerged nozzle and stopper rod of the tundish, which needs to be solved urgently. Summary of the invention

[0004] The embodiments of the present invention provide a control method, device and equipment for continuous casting equipment, which solve the technical problem that inclusions are easily attached to the submerged nozzle and stopper rod of the tundish.

[0005] In the first aspect, an embodiment of the present invention provides a control method for a continuous casting equipment, the continuous casting equipment comprising a tundish, a negative electrode assembly and a power supply, the tundish comprising a stopper rod and an immersed water nozzle, the negative electrode assembly is fixedly arranged on the tundish and in contact with the molten steel in the tundish, the positive electrode of the power supply is respectively connected to the stopper rod and the immersed water nozzle, and the negative electrode of the power supply is connected to the negative electrode assembly, the method comprising: when the continuous casting equipment is casting, obtaining a current height of the stopper rod, wherein a larger current height indicates a higher risk of blockage of the immersed water nozzle; and based on the current height, controlling a current duty cycle of the power supply.

[0006] In combination with the first aspect of the present invention, in some embodiments, controlling the current duty cycle of the power supply based on the current height includes: obtaining an initial height of the stopper rod, the initial height being obtained at an initial moment of casting by the continuous casting equipment, and the initial height being less than or equal to the current height; and controlling the current duty cycle of the power supply based on the initial height and the current height.

[0007] In combination with the first aspect of the present invention, in some embodiments, controlling the current duty cycle of the power supply based on the initial altitude and the current altitude includes: obtaining a duty cycle lower limit value and a duty cycle upper limit value set for the power supply, the duty cycle lower limit value being less than the duty cycle upper limit value; if the current altitude is less than or equal to a preset first altitude threshold, using the duty cycle lower limit value as the current duty cycle; if the current altitude is greater than the first altitude threshold and less than a preset second altitude threshold, determining the current duty cycle based on the initial altitude and the current altitude, the second altitude threshold being greater than the first altitude threshold; if the current altitude is greater than or equal to the second altitude threshold, using the duty cycle upper limit value as the current duty cycle.

[0008] In combination with the first aspect of the present invention, in some embodiments, determining the current duty cycle based on the initial height and the current height includes: determining a current height deviation between the initial height and the current height; based on the current height deviation, determining the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is linear and continuous, and the greater the height deviation, the greater the duty cycle.

[0009] In combination with the first aspect of the present invention, in some embodiments, determining the current duty cycle based on the initial height and the current height includes: determining a current height deviation between the initial height and the current height; based on the current height deviation, determining the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is nonlinear and continuous, and the greater the height deviation, the greater the tendency of increasing the duty cycle.

[0010] In combination with the first aspect of the present invention, in some embodiments, determining the current duty cycle based on the initial height and the current height includes: determining a current height deviation between the initial height and the current height; based on the current height deviation, determining the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is nonlinear and continuous, and the greater the height deviation, the smaller the increasing trend of the duty cycle.

[0011] In combination with the first aspect of the present invention, in some embodiments, determining the current duty cycle based on the initial height and the current height includes: determining a current height deviation between the initial height and the current height; based on the current height deviation, determining the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is nonlinear and discontinuous, and the duty cycle increases in a step-by-step manner as the height deviation increases.

[0012] In combination with the first aspect of the present invention, in some embodiments, obtaining the lower limit value and the upper limit value of the duty cycle set for the power supply includes: obtaining the carbon content of the molten steel; based on the carbon content, determining the lower limit value and the upper limit value of the duty cycle, wherein the smaller the carbon content, the larger the lower limit value and the upper limit value of the duty cycle.

[0013] In the second aspect, an embodiment of the present invention provides a control device for a continuous casting equipment, the continuous casting equipment comprising a tundish, a negative electrode assembly and a power supply, the tundish comprising a stopper rod and an immersed water nozzle, the negative electrode assembly is fixedly arranged on the tundish and in contact with the molten steel in the tundish, the positive electrode of the power supply is respectively connected to the stopper rod and the immersed water nozzle, and the negative electrode of the power supply is connected to the negative electrode assembly, the device comprising: a height acquisition unit, for acquiring a current height of the stopper rod when the continuous casting equipment is casting, wherein a larger current height indicates a higher risk of blockage of the immersed water nozzle; a power supply control unit, for controlling a current duty cycle of the power supply based on the current height.

[0014] In a third aspect, an embodiment of the present invention provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements any one of the methods described in the first aspect when executing the computer program.

[0015] One or more technical solutions provided by the embodiments of the present invention achieve at least the following technical effects or advantages:

[0016] In a control method for a continuous casting device provided in an embodiment of the present invention, the continuous casting device includes a tundish, a negative electrode assembly and a power supply, the tundish includes a stopper rod and an immersion nozzle, the negative electrode assembly is fixedly arranged in the tundish and in contact with the molten steel in the tundish, the positive electrode of the power supply is respectively connected to the stopper rod and the immersion nozzle, and the negative electrode of the power supply is connected to the negative electrode assembly, and the method includes: when the continuous casting device is casting, the current height of the stopper rod is obtained, wherein the greater the current height, the higher the risk of blockage of the immersion nozzle; based on the current height, the current duty cycle of the power supply is controlled. Since the stopper rod and the immersion nozzle are both connected to the positive electrode of the power supply, a positive electric field will be formed in the vicinity of the stopper rod and the immersion nozzle, which can repel positively charged particles. Since most of the inclusions are positively charged Al2O3 inclusions, the inclusions are not easy to adhere to the immersion nozzle and the stopper rod of the tundish. In addition, since the negative electrode assembly can attract positively charged Al2O3 inclusions, the inclusions are further prevented from being attached to the submerged nozzle and stopper rod of the tundish. Therefore, the possibility of inclusions being attached to the submerged nozzle and stopper rod of the tundish is reduced.

[0017] In addition, the greater the current height of the stopper rod, the higher the risk of blockage of the submerged water inlet. When the risk of blockage is high, a larger duty cycle is selected to increase the current intensity, thereby reducing the possibility of inclusions adhering to the submerged water inlet and the stopper rod of the tundish. When the risk of blockage is low, a smaller duty cycle is selected to reduce the current intensity, which can save electricity. Therefore, controlling the current duty cycle of the power supply based on the current height not only reduces the amount of inclusions adhering to the submerged water inlet or the stopper rod, but also selects a suitable duty cycle according to actual conditions to adjust the current intensity of the power supply, thereby avoiding wasting electricity. Therefore, the beneficial effect of balancing power saving and reducing the amount of inclusions adhering is also achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 is a flow chart of a control method for continuous casting equipment in an embodiment of the present invention;

[0020] Figure 2 This is a first schematic diagram of the corresponding relationship in an embodiment of the present invention;

[0021] Figure 3 A second schematic diagram of the corresponding relationship in the embodiment of the present invention;

[0022] Figure 4 This is a third schematic diagram of the corresponding relationship in the embodiment of the present invention;

[0023] Figure 5 is a fourth schematic diagram of the corresponding relationship in the embodiment of the present invention;

[0024] Figure 6 for Figure 1 Schematic diagram of continuous casting equipment;

[0025] Figure 7 It is a functional module diagram of a control device for continuous casting equipment in an embodiment of the present invention;

[0026] Figure 8 Schematic diagram of the structure of an electronic device in an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0029] The embodiment of the present invention provides a control method for a continuous casting device, wherein the continuous casting device comprises a tundish, a negative electrode assembly and a power supply, wherein the tundish comprises a stopper rod and an immersion nozzle, the negative electrode assembly is fixedly arranged in the tundish and contacts with molten steel in the tundish, the positive electrode of the power supply is respectively connected to the stopper rod and the immersion nozzle, and the negative electrode of the power supply is connected to the negative electrode assembly, and the reference Figure 1 As shown, the method includes the following steps S101-S102:

[0030] S101: When the continuous casting device is casting, the current height of the stopper rod is obtained, wherein the larger the current height is, the higher the risk of blockage of the submerged nozzle is.

[0031] It should be noted that the continuous casting equipment can automatically control the height of the stopper rod according to the molten steel flow rate of the submerged nozzle. Specifically, when there are many inclusions attached to the submerged nozzle or the stopper rod, the molten steel flow rate of the submerged nozzle is reduced, and the risk of clogging of the submerged nozzle is increased. At this time, the continuous casting equipment automatically controls the height of the stopper rod to increase. Therefore, the greater the current height, the higher the risk of clogging of the submerged nozzle.

[0032] It should be noted that the height refers to the distance between the head of the stopper rod and the bottom of the submerged nozzle.

[0033] S102: Based on the current altitude, control the current duty cycle of the power supply.

[0034] In some implementations, step S102 may include the following steps S1021 to S1022:

[0035] S1021: Obtaining an initial height of the stopper rod, where the initial height is obtained at the initial moment of casting of the continuous casting equipment, and the initial height is less than or equal to the current height.

[0036] S1022: Based on the initial altitude and the current altitude, control the current duty cycle of the power supply.

[0037] In some implementations, step S1022 may include the following steps A to D:

[0038] Step A: Obtain a duty cycle lower limit value and a duty cycle upper limit value set for a power supply, wherein the duty cycle lower limit value is smaller than the duty cycle upper limit value.

[0039] In some embodiments, obtaining a lower limit value and an upper limit value of the duty cycle set for a power supply may include: obtaining the carbon content of the molten steel; and determining a lower limit value and an upper limit value of the duty cycle based on the carbon content, wherein the smaller the carbon content, the larger the lower limit value and the upper limit value of the duty cycle.

[0040] It should be noted that the lower limit of the duty cycle may be 40% to 60%, and the upper limit of the duty cycle may be 90% to 100%.

[0041] It should be noted that according to the law of carbon-oxygen balance, the lower the carbon content, the higher the oxygen content, and the more oxidized inclusions. At this time, the duty cycle needs to be increased to increase the current intensity, so as to effectively prevent inclusions from adhering to the submerged nozzle and stopper rod of the tundish. Therefore, the lower limit and upper limit of the duty cycle are determined based on the carbon content, so as to select a more suitable duty cycle, avoid the attachment of inclusions due to too low current intensity, and avoid energy waste due to too high current intensity. Therefore, a balance is achieved between saving energy and reducing the possibility of inclusion attachment.

[0042] Step B: If the current altitude is less than or equal to the preset first altitude threshold, the duty cycle lower limit is used as the current duty cycle.

[0043] Step C: If the current altitude is greater than the first altitude threshold and less than a preset second altitude threshold, determine the current duty cycle based on the initial altitude and the current altitude, and the second altitude threshold is greater than the first altitude threshold.

[0044] It is understandable that there are multiple implementations for determining the current duty cycle based on the initial altitude and the current altitude, which are described below by way of example:

[0045] Implementation method 1:

[0046] Determine a current height deviation between an initial height and a current height; based on the current height deviation, determine a current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is linear and continuous, and the greater the height deviation, the greater the duty cycle.

[0047] refer to Figure 2 As shown, Figure 2 This is a first schematic diagram of the corresponding relationship in an embodiment of the present invention, wherein the first height deviation is the height deviation corresponding to the first height threshold, and the second height deviation is the height deviation corresponding to the second height threshold. When the current height is greater than the first height threshold and less than the preset second height threshold, the corresponding relationship is linear and continuous, and the greater the height deviation, the greater the duty cycle, wherein the corresponding relationship can be expressed by the following formula (1):

[0048] η=η min +k×|P-P0| (1);

[0049] Where, η is the current duty cycle, η min is the lower limit of the duty cycle, k is the preset coefficient, the value range of k can be 2.0% to 3.0%, P is the current altitude, and P0 is the initial altitude.

[0050] It should be noted that every time the height deviation increases by a certain value, the duty cycle also increases by a certain value. Through a linear and continuous corresponding relationship, the control logic of the duty cycle is simplified and the complexity of program implementation is reduced.

[0051] Implementation method 2:

[0052] Determine the current height deviation between the initial height and the current height; based on the current height deviation, determine the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is nonlinear and continuous, and the greater the height deviation, the greater the increasing trend of the duty cycle.

[0053] refer to Figure 3 As shown, Figure 3 This is a second schematic diagram of the corresponding relationship in an embodiment of the present invention, wherein the first height deviation is the height deviation corresponding to the first height threshold, and the second height deviation is the height deviation corresponding to the second height threshold. When the current height is greater than the first height threshold and less than the preset second height threshold, the corresponding relationship is nonlinear and continuous, and the greater the height deviation, the greater the increase trend of the duty cycle.

[0054] It should be noted that if the molten steel is used to produce low-level products, such as low-level automobile plates, a certain amount of inclusions in the molten steel is allowed, and the quality of the ingot is allowed to be low. When the current height is near the first height threshold, since the quality of the ingot is allowed to be low, if the duty cycle is quickly increased, although the quality level of the ingot is improved, it has no practical production significance and wastes electricity. Therefore, when the current height is near the first height threshold, the duty cycle is slowly increased to ensure that the quality of the ingot is at least qualified and avoid wasting electricity. When the current height is near the second height threshold, the duty cycle is quickly increased to remove a certain amount of inclusions in the molten steel, so it is also possible to avoid the ingot quality being unqualified due to the presence of more inclusions in the molten steel, and to a certain extent, it can also avoid the attachment of inclusions to the submerged nozzle and stopper rod of the tundish, so it is also possible to avoid the ingot quality being unqualified due to the attachment of inclusions. Therefore, it is possible to save electricity while ensuring the quality of the ingot.

[0055] Implementation method three:

[0056] Determine the current height deviation between the initial height and the current height; based on the current height deviation, determine the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is nonlinear and continuous, and the greater the height deviation, the smaller the increasing trend of the duty cycle.

[0057] refer to Figure 4 As shown, Figure 4 This is a third schematic diagram of the corresponding relationship in the embodiment of the present invention, wherein the first height deviation is the height deviation corresponding to the first height threshold, and the second height deviation is the height deviation corresponding to the second height threshold. When the current height is greater than the first height threshold and less than the preset second height threshold, the corresponding relationship is nonlinear and continuous, and the greater the height deviation, the smaller the increasing trend of the duty cycle.

[0058] It should be noted that if molten steel is used to produce high-level products, such as high-level automotive plates, the molten steel is not allowed to contain too many inclusions at this time, and the quality requirements for the ingot are high. When the current height is near the first height threshold, the ingot quality is allowed to be higher, and the greater the current height, the higher the risk of blockage of the submerged nozzle, that is, the greater the possibility of a decrease in the quality of the ingot. Therefore, it is necessary to quickly increase the duty cycle to increase the current intensity, thereby increasing the positive electric field strength in the vicinity of the stopper rod and the submerged nozzle, and minimizing the possibility of inclusions adhering to the submerged nozzle and the stopper rod of the tundish. At the same time, the adsorption force of the negative electrode assembly on positively charged inclusions is increased, minimizing the inclusion content of the molten steel. In this way, the excellent quality of the ingot is guaranteed.

[0059] Implementation method 4:

[0060] Determine a current height deviation between an initial height and a current height; based on the current height deviation, determine a current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is nonlinear and discontinuous, and the duty cycle increases in a step-by-step manner as the height deviation increases.

[0061] refer to Figure 5 As shown, Figure 5 This is a fourth schematic diagram of the corresponding relationship in the embodiment of the present invention, wherein the first height deviation is the height deviation corresponding to the first height threshold, and the second height deviation is the height deviation corresponding to the second height threshold. When the current height is greater than the first height threshold and less than the preset second height threshold, the corresponding relationship is nonlinear and discontinuous, and the duty cycle increases stepwise as the height deviation increases.

[0062] It should be noted that due to calculation errors or detection errors, the current height deviation value will fluctuate, so the current height deviation will fluctuate in a small range. If the duty cycle is adjusted accordingly every time a small fluctuation in the height deviation is detected, the workload of the power supply will increase, resulting in a shortened service life of the power supply, and thus shortening the service life of the continuous casting equipment. Therefore, this implementation method limits the duty cycle to increase in a step-by-step manner as the height deviation increases, avoiding frequent duty cycle adjustments due to small fluctuations in the height deviation, reducing the workload of the continuous casting equipment, and extending the service life of the continuous casting equipment.

[0063] It should be noted that Figure 2 , Figure 3 , Figure 4 as well as Figure 5 It shows that the corresponding duty cycle changes continuously near the first height deviation, and the corresponding duty cycle changes continuously near the second height deviation, that is, the smallest duty cycle in the corresponding relationship is infinitely close to the lower limit of the duty cycle, and the largest duty cycle in the corresponding relationship is infinitely close to the upper limit of the duty cycle. In other embodiments, the smallest duty cycle in the corresponding relationship can be significantly greater than or significantly less than the lower limit of the duty cycle, and the largest duty cycle in the corresponding relationship can be significantly greater than or significantly less than the upper limit of the duty cycle. In addition, the corresponding relationship can be expressed using a formula, such as the above figure Figure 2 , Figure 3 , Figure 4 as well as Figure 5 In addition, the corresponding relationship may not be expressed using a formula.

[0064] Step D: If the current altitude is greater than or equal to the second altitude threshold, the duty cycle upper limit is used as the current duty cycle.

[0065] It should be noted that the type of steel in the molten steel may be ultra-low carbon steel, and the molten steel of ultra-low carbon steel is more susceptible to the phenomenon of inclusion attachment; wherein the carbon content of the ultra-low carbon steel may be 0 to 0.0030%.

[0066] In some embodiments, the negative electrode assembly may include: a negative electrode material, which is a conductive refractory material and is in contact with the molten steel, and the negative electrode material is used to absorb inclusions in the molten steel; a negative electrode interface, which is provided at one end of the negative electrode material and is not in contact with the molten steel, and the negative electrode interface is connected to the negative electrode of the power supply. It should be noted that since the negative electrode material also has the characteristic of absorbing inclusions in the molten steel when there is no current, the inclusions can be quickly absorbed by the negative electrode assembly, reducing the inclusion content in the molten steel, and thus improving the quality of the ingot.

[0067] In some embodiments, the number of negative electrode assemblies is multiple, and the negative electrode assembly may include: a first negative electrode subassembly, the negative electrode of the power source is connected to the first negative electrode subassembly, and the first negative electrode subassembly is fixedly arranged on the first side of the tundish; a second negative electrode subassembly, the negative electrode of the power source is connected to the second negative electrode subassembly, and the second negative electrode subassembly is fixedly arranged on the second side of the tundish, and the second side is the opposite side of the first side. It should be noted that since the number of negative electrode assemblies is multiple, inclusions can be quickly adsorbed by the negative electrode assemblies, reducing the inclusion content in the molten steel, and thus improving the quality of the ingot.

[0068] In some embodiments, the output voltage of the power supply is 0-35V, and the output current is 0-400A. It should be noted that limiting the output voltage of the power supply to 0-35V will not cause major safety accidents even if the personnel on duty accidentally touch the power supply, thereby improving the safety of the continuous casting equipment.

[0069] In some embodiments, the power supply is used to output a pulse current, and the frequency of the pulse current may be 0 to 50,000 Hz, and the duty cycle may be 10% to 100%.

[0070] It should be noted that, when the power supply is used to output direct current, under the action of the electric field, the inclusions in the molten steel mainly move in a left-right direction. At this time, the negative electrode component can absorb a certain amount of inclusions, but there are still uncharged inclusions, negatively charged inclusions and some positively charged inclusions that are not absorbed by the negative electrode component. In contrast, when the power supply is used to output pulse current, if the pulse current is of high current intensity, the inclusions in the molten steel mainly move in a left-right direction. At this time, the negative electrode component can absorb a certain amount of inclusions. If the pulse current is of low current intensity, the inclusions float up under the action of buoyancy and combine with the molten steel protective slag, further reducing the inclusion content in the molten steel. Therefore, when the power supply is used to output pulse current, the possibility of inclusions adhering to the submerged nozzle and stopper rod of the tundish is further reduced.

[0071] in addition, Figure 6 for Figure 1 Schematic diagram of the continuous casting equipment. For the power supply, tundish, submerged nozzle, stopper rod and negative electrode components, please refer to Figure 6 .

[0072] It should be noted that the steel industry, as a pillar industry of the national economy, plays a vital role. It is not only a key force in promoting scientific and technological progress, promoting national rejuvenation and national prosperity, but also a cornerstone for ensuring the sustained and efficient development of my country's economy. Among them, the independent production capacity of high-quality steel is directly related to the country's strategic security and core competitiveness. However, there is still a certain gap between my country's independent research and development and production of high-quality steel and the international advanced level. This situation is partly attributed to the problem of large-size inclusions that are difficult to avoid in the steel manufacturing process, which seriously affects the quality of finished steel and limits the international competitiveness of my country's steel industry. Continuous casting technology, as a revolutionary breakthrough in the steel production process, has greatly improved the efficiency and quality control level of steel production. However, in the continuous casting process of ultra-low carbon steel, although aluminum particle deoxidation is a common deoxidation method to reduce the oxygen content in the molten steel, this process is also accompanied by the generation of Al2O3 inclusions. These fine oxide inclusions are difficult to completely remove and become the main obstacle to the smooth flow of continuous casting nozzles. The blockage of the nozzle will not only lead to the imbalance of the flow field during the casting process, causing liquid level fluctuations and slag defects, but also force the production to be interrupted for nozzle replacement, which significantly reduces production efficiency and increases costs. If the nozzle blockage is avoided only by improving the nozzle lining material, changing the nozzle structure, optimizing the three-way argon parameters, etc., the problem is that the dynamic changes in the continuous casting process are not fully considered, especially the changes in the micro-blocking of the nozzle in the later stage of continuous casting, resulting in limited anti-blocking effect. The embodiment of the present invention closely tracks the position change of the stopper rod during the casting process, dynamically adjusts the duty cycle of the pulse power supply, and dynamically optimizes the current output mode to adapt to the specific needs of different stages of continuous casting, especially when the nozzle begins to show signs of blockage in the later stage of continuous casting. The current parameters can be adjusted in real time to effectively suppress the trend of nozzle blockage and ensure the continuity and stability of the casting process. It can significantly improve the production efficiency of ultra-low carbon steel continuous casting, reduce production interruptions caused by nozzle blockage, and at the same time improve the quality of the ingot, and promote the transformation and upgrading of the industry to a more efficient and intelligent direction.

[0073] In order to enhance the understanding of the embodiments of the present invention, the following examples are given: Figure 2 As an example, referring to formula (1), the preset coefficient k is 2.5%, η minThe value is 50%. In a certain casting process of 7 furnaces of ultra-low carbon steel, the cross-section is 230mm×1600mm, the casting speed is 1.4m / min, ultra-low carbon steel protective slag is used, the superheat is controlled at about 25℃-40℃, and at the beginning of the first furnace casting, the pulse current is set to 100A according to the regulations. As casting progresses, after the casting speed of the first furnace stabilizes, the initial height P0 of the tundish stopper rod is detected to be 61 mm, the pulse voltage is 12 V, and the duty cycle is 50%. As casting progresses, the height of the stopper rod changes to 65 mm, that is, the P value is 65 mm. According to formula (1), it can be determined that the current duty cycle is 60%. Therefore, the control system automatically adjusts the pulse current duty cycle from the initial 50% to 60%. As casting continues, the height of the stopper rod rises to 84 mm at a certain moment. At this time, the P value is 84 mm. According to formula (1), the current duty cycle is 107.5%. However, since it cannot exceed 100%, the control system automatically adjusts the pulse current duty cycle from the initial 50% to 100%, that is, DC current. After implementing this optimized control scheme, the stopper rod changes smoothly and the stopper rod rise control is stable, that is, the formation of oxide inclusions on the inner wall of the nozzle is reduced. The entire casting process is smooth and there is no nozzle blockage.

[0074] In a control method of a continuous casting device provided by an embodiment of the present invention, the continuous casting device includes a tundish, a negative electrode assembly and a power supply, the tundish includes a stopper rod and an immersion nozzle, the negative electrode assembly is fixedly arranged in the tundish and contacts the molten steel in the tundish, the positive electrode of the power supply is respectively connected to the stopper rod and the immersion nozzle, and the negative electrode of the power supply is connected to the negative electrode assembly, and the method includes: when the continuous casting device is casting, the current height of the stopper rod is obtained, wherein the greater the current height, the higher the risk of blockage of the immersion nozzle; based on the current height, the current duty cycle of the power supply is controlled. Since the stopper rod and the immersion nozzle are both connected to the positive electrode of the power supply, a positive electric field will be formed in the vicinity of the stopper rod and the immersion nozzle, which can repel positively charged particles. Since most of the inclusions are positively charged Al2O3 inclusions, the inclusions are not easy to adhere to the immersion nozzle and the stopper rod of the tundish. In addition, since the negative electrode assembly can attract positively charged Al2O3 inclusions, the inclusions are further prevented from being attached to the submerged nozzle and stopper rod of the tundish. Therefore, the possibility of inclusions being attached to the submerged nozzle and stopper rod of the tundish is reduced.

[0075] In addition, the greater the current height of the stopper rod, the higher the risk of blockage of the submerged water inlet. When the risk of blockage is high, a larger duty cycle is selected to increase the current intensity, thereby reducing the possibility of inclusions adhering to the submerged water inlet and the stopper rod of the tundish. When the risk of blockage is low, a smaller duty cycle is selected to reduce the current intensity, which can save electricity. Therefore, controlling the current duty cycle of the power supply based on the current height not only reduces the amount of inclusions adhering to the submerged water inlet or the stopper rod, but also selects a suitable duty cycle according to actual conditions to adjust the current intensity of the power supply, thereby avoiding wasting electricity. Therefore, the beneficial effect of balancing power saving and reducing the amount of inclusions adhering is also achieved.

[0076] Based on the same inventive concept, Figure 7 As shown, an embodiment of the present invention provides a control device 10 for a continuous casting equipment, the continuous casting equipment includes a tundish, a negative electrode assembly and a power supply, the tundish includes a stopper rod and an immersed water nozzle, the negative electrode assembly is fixedly arranged in the tundish and in contact with the molten steel in the tundish, the positive electrode of the power supply is respectively connected to the stopper rod and the immersed water nozzle, and the negative electrode of the power supply is connected to the negative electrode assembly. The control device 10 of the continuous casting equipment includes: a height acquisition unit 110, used to acquire the current height of the stopper rod when the continuous casting equipment is casting, wherein the larger the current height is, the higher the risk of blockage of the immersed water nozzle is; a power supply control unit 120, used to control the current duty cycle of the power supply based on the current height.

[0077] It can be understood that the power control unit 120 includes: an initial acquisition subunit, used to obtain the initial height of the stopper rod, the initial height is obtained at the initial moment of casting of the continuous casting equipment, and the initial height is less than or equal to the current height; a control subunit, used to control the current duty cycle of the power supply based on the initial height and the current height.

[0078] It can be understood that the control subunit includes: a threshold acquisition module, which is used to obtain the lower limit value of the duty cycle and the upper limit value of the duty cycle set for the power supply, and the lower limit value of the duty cycle is smaller than the upper limit value of the duty cycle; a first determination module, which is used to use the lower limit value of the duty cycle as the current duty cycle if the current altitude is less than or equal to a preset first altitude threshold; a second determination module, which is used to determine the current duty cycle based on the initial altitude and the current altitude if the current altitude is greater than the first altitude threshold and less than a preset second altitude threshold, and the second altitude threshold is greater than the first altitude threshold; a third determination module, which is used to use the upper limit value of the duty cycle as the current duty cycle if the current altitude is greater than or equal to the second altitude threshold.

[0079] It can be understood that the second determination module is specifically used to: determine the current height deviation between the initial height and the current height; based on the current height deviation, determine the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is linear and continuous, and the greater the height deviation, the greater the duty cycle. Or determine the current height deviation between the initial height and the current height; based on the current height deviation, determine the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is nonlinear and continuous, and the greater the height deviation, the greater the increasing trend of the duty cycle. Or determine the current height deviation between the initial height and the current height; based on the current height deviation, determine the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is nonlinear and continuous, and the greater the height deviation, the smaller the increasing trend of the duty cycle. Or determine the current height deviation between the initial height and the current height; based on the current height deviation, determine the current duty cycle from a preset corresponding relationship; wherein the corresponding relationship is nonlinear and discontinuous, and the duty cycle increases stepwise with the increase of the height deviation.

[0080] It can be understood that the threshold acquisition module is specifically used to: obtain the carbon content of molten steel; based on the carbon content, determine the lower limit value and the upper limit value of the duty cycle, wherein the smaller the carbon content, the larger the lower limit value and the upper limit value of the duty cycle.

[0081] It should be understood that more implementation details of the control device 10 of the continuous casting equipment in the embodiment of the present invention refer to the control method of the continuous casting equipment described above, and for the sake of brevity of the specification, they are not repeated here.

[0082] Based on the same inventive concept, an embodiment of the present invention further provides an electronic device, such as Figure 8 As shown, it includes a memory 804, a processor 802, and a computer program stored in the memory 804 and executable on the processor 802. The processor 802 executes the program to implement the steps described in any implementation of the control method of the continuous casting equipment.

[0083] Among them, Figure 8In the embodiment of the present invention, a bus architecture (represented by bus 800) is shown, which may include any number of interconnected buses and bridges, and bus 800 links various circuits including one or more processors represented by processor 802 and memory represented by memory 804. Bus 800 may also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. Bus interface 805 provides an interface between bus 800 and receiver 801 and transmitter 803. Receiver 801 and transmitter 803 may be the same element, namely a transceiver, providing a unit for communicating with various other devices over a transmission medium. Processor 802 is responsible for managing bus 800 and general processing, while memory 804 may be used to store data used by processor 802 when performing operations.

[0084] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored as one or more instructions or codes on a computer-readable medium or transmitted via a computer-readable medium. Other examples and implementations are within the scope and spirit of the present invention and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these. In addition, each functional unit may be integrated into a processing unit, each unit may exist physically separately, or two or more units may be integrated into one unit.

[0085] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0086] The units described as separate components may or may not be physically separated, and the components of the control device may or may not be physical units, that is, they may be located in one place or distributed in multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0087] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0088] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. A control method for continuous casting equipment, characterized in that: The continuous casting equipment comprises a tundish, a negative electrode assembly and a power source, the tundish comprises a stopper rod and an immersion nozzle, the negative electrode assembly is fixedly arranged on the tundish and contacts with molten steel in the tundish, the positive electrode of the power source is respectively connected to the stopper rod and the immersion nozzle, the negative electrode of the power source is connected to the negative electrode assembly, and the method comprises: When the continuous casting device is casting, obtaining a current height of the stopper rod, wherein the greater the current height is, the higher the risk of blockage of the submerged nozzle is; Based on the current altitude, a current duty cycle of the power source is controlled.

2. The control method of continuous casting equipment according to claim 1, characterized in that: The controlling the current duty cycle of the power supply based on the current altitude includes: Acquire an initial height of the stopper rod, wherein the initial height is acquired at an initial moment of casting by the continuous casting device, and the initial height is less than or equal to the current height; Based on the initial altitude and the current altitude, a current duty cycle of the power source is controlled.

3. The control method of continuous casting equipment according to claim 2, characterized in that: The controlling the current duty cycle of the power supply based on the initial altitude and the current altitude comprises: Acquire a duty cycle lower limit value and a duty cycle upper limit value set for the power supply, wherein the duty cycle lower limit value is smaller than the duty cycle upper limit value; If the current altitude is less than or equal to a preset first altitude threshold, taking the duty cycle lower limit as the current duty cycle; If the current altitude is greater than the first altitude threshold and less than a preset second altitude threshold, determining the current duty cycle based on the initial altitude and the current altitude, and the second altitude threshold is greater than the first altitude threshold; If the current altitude is greater than or equal to the second altitude threshold, the duty cycle upper limit value is used as the current duty cycle.

4. The control method of continuous casting equipment according to claim 3, characterized in that: The determining the current duty cycle based on the initial altitude and the current altitude comprises: determining a current altitude deviation between the initial altitude and the current altitude; Based on the current height deviation, determining the current duty cycle from a preset corresponding relationship; The corresponding relationship is linear and continuous, and the greater the height deviation, the greater the duty cycle.

5. The control method of continuous casting equipment according to claim 3, characterized in that: The determining the current duty cycle based on the initial altitude and the current altitude comprises: determining a current altitude deviation between the initial altitude and the current altitude; Based on the current height deviation, determining the current duty cycle from a preset corresponding relationship; The corresponding relationship is nonlinear and continuous, and the greater the height deviation, the greater the increasing trend of the duty cycle.

6. The control method of continuous casting equipment according to claim 3, characterized in that: The determining the current duty cycle based on the initial altitude and the current altitude comprises: determining a current altitude deviation between the initial altitude and the current altitude; Based on the current height deviation, determining the current duty cycle from a preset corresponding relationship; The corresponding relationship is nonlinear and continuous, and the greater the height deviation, the smaller the increasing trend of the duty cycle.

7. The control method of continuous casting equipment according to claim 3, characterized in that: The determining the current duty cycle based on the initial altitude and the current altitude comprises: determining a current altitude deviation between the initial altitude and the current altitude; Based on the current height deviation, determining the current duty cycle from a preset corresponding relationship; The corresponding relationship is nonlinear and discontinuous, and the duty cycle increases in a step-by-step manner as the height deviation increases.

8. The control method of the continuous casting equipment according to any one of claims 3 to 7, characterized in that: The obtaining of a duty cycle lower limit value and a duty cycle upper limit value set for the power supply includes: Obtaining the carbon content of the molten steel; Based on the carbon content, the duty cycle lower limit value and the duty cycle upper limit value are determined, wherein the smaller the carbon content is, the larger the duty cycle lower limit value and the duty cycle upper limit value are.

9. A control device for continuous casting equipment, characterized in that: The continuous casting equipment comprises a tundish, a negative electrode assembly and a power source, wherein the tundish comprises a stopper rod and an immersion nozzle, the negative electrode assembly is fixedly arranged on the tundish and contacts with molten steel in the tundish, the positive electrode of the power source is respectively connected to the stopper rod and the immersion nozzle, and the negative electrode of the power source is connected to the negative electrode assembly, and the device comprises: a height acquisition unit, used for acquiring the current height of the stopper rod when the continuous casting device is casting, wherein the greater the current height is, the higher the risk of blockage of the submerged nozzle is; A power control unit is used to control a current duty cycle of the power supply based on the current altitude.

10. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method according to any one of claims 1 to 8 when executing the computer program.

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