Slag Vertical Mill Control System and Method

Abstract

This invention proposes a control system and method for a slag vertical mill. The system includes: a vertical mill operating parameter acquisition and judgment loop for judging whether at least one of the acquired parameters—feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current, and main exhaust fan current—is abnormal; a main motor current control loop for controlling the main roller pressure, mill target temperature, and feed rate through the main motor current; a mill outlet temperature control loop for correcting the mill target temperature and controlling the mill outlet temperature by adjusting the deviation of the main motor current; a mill internal ventilation control loop for controlling the classifier speed, main exhaust fan speed, and feed rate through the mill internal pressure difference and the main exhaust fan current; and a vibration control loop for controlling the classifier speed, main roller pressure, and feed rate through the mill vibration value. This system improves the automation level of the grinding process.

Description

Technical Field

[0001] This invention relates to the field of slag vertical mill production, and more particularly to a slag vertical mill control system and method. Background Technology

[0002] Slag vertical mill production is a multi-variable coupled process. Current control systems have achieved basic automated closed-loop control, such as feed rate closed-loop, main roller pressure closed-loop, and speed closed-loop. However, there is no mature system for regulating the process parameters of slag vertical mill production, or the system does not cover the process model comprehensively, making it impossible to achieve fully automated production, i.e., one-click powder making function.

[0003] like Figure 1 As shown, the existing control system judges the feed rate, mill vibration value, material layer thickness, mill inlet / outlet temperature, and mill internal pressure difference. If any of these conditions are met, the feed rate and hot air damper are adjusted through two loops: material layer control and temperature control. This system is effective to some extent, but it has significant shortcomings due to the limited number of factors considered and the insufficient number of control loops.

[0004] 1. The thickness of the material layer is difficult to obtain directly. Most vertical mills do not have material layer thickness detection. If there is no material layer thickness detection, this method cannot be used.

[0005] 2. The automatic circuit only controls the feeding amount and the hot air baffle. Since the feeding amount needs to pass through a belt about 100 meters long, it cannot respond in time when vibration occurs.

[0006] 3. The classifier speed and cold air valve opening are manually adjustable, requiring frequent manual operation and making one-button powder production impossible.

[0007] 4. The grinding pressure and main exhaust fan were not controlled by a system, requiring a large amount of manual adjustment. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention proposes a control system and method for slag vertical mills. This method achieves automatic calculation and automatic control of all process parameters in the slag vertical mill production process by decoupling analysis and modeling of the production process parameters.

[0009] To achieve the above objectives, the present invention provides a slag vertical mill control system, comprising:

[0010] A vertical mill operating parameter acquisition and judgment loop is used to determine whether there is at least one abnormal value among the collected feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current and main exhaust fan current.

[0011] A main motor current control circuit is connected to the vertical mill operating condition parameter acquisition and judgment circuit. The main motor current control circuit is used to control the main roller pressure, the target temperature inside the mill, and the feed rate through the main motor current.

[0012] A mill outlet temperature control loop is connected to the vertical mill operating condition parameter acquisition and judgment loop and the main motor current control loop. The mill outlet temperature control loop is used to correct the target temperature inside the mill by the deviation of the main motor current and control the mill outlet temperature.

[0013] A mill internal ventilation control circuit is connected to the vertical mill operating condition parameter acquisition and judgment circuit. The mill internal ventilation control circuit is used to control the classifier speed, the main exhaust fan speed, and the feed rate through the mill internal pressure difference and the main exhaust fan current.

[0014] A vibration control circuit is connected to the vertical mill operating condition parameter acquisition and judgment circuit. The vibration control circuit is used to control the classifier speed, the main roller pressure, and the feed rate through the mill vibration value.

[0015] Optionally, the main motor current control circuit is configured to include:

[0016] A main motor power protection control model is configured such that the input data is the main motor current, and the output data is the feed rate and the main roller pressure. The main motor power protection control model is used to reduce the main roller pressure and / or reduce the feed rate when the main motor current exceeds the rated power.

[0017] A motor current target control model is configured such that the input data is the main motor current, and the output data is the feed rate and the target temperature inside the mill. The motor current target control model is used to control the target temperature inside the mill through the average value of the main motor current and the direction of change of the main motor current to achieve a faster response, and to assist in the balanced control of the feed rate.

[0018] Optionally, the mill outlet temperature control loop is configured to include:

[0019] A target temperature correction model is configured such that the input data is the main motor current, and the target temperature correction model is used to perform feedforward control by controlling the target temperature inside the mill through the main motor current.

[0020] A temperature control model, connected to the target temperature correction model, is configured such that the input data are the main motor current and the temperature deviation between the target temperature inside the mill and the mill outlet temperature after feedforward correction. The temperature control model is used to control the mill outlet temperature by the direction of change of the main motor current and the temperature deviation feedback.

[0021] Optionally, the temperature control model uses a fuzzy controller.

[0022] Optionally, the slag vertical mill control system further includes:

[0023] An exhaust fan regulating unit, connected to the mill outlet temperature control circuit, is used to regulate the mill outlet temperature and includes:

[0024] Circulating air valve

[0025] Hot blast furnace gas valve

[0026] Cold air valve, exhaust gas valve;

[0027] Among them, the circulating air valve and the hot blast stove gas valve have the highest priority;

[0028] The cold air valve and exhaust valve have the next highest priority.

[0029] Optionally, the mill internal ventilation control circuit is used to control the classifier speed, the main exhaust fan speed, and the feed rate through the mill internal pressure difference and the main exhaust fan current, including:

[0030] When the internal pressure difference in the mill exceeds a first pressure difference threshold and the current of the main exhaust fan is less than a first current threshold.

[0031] Reduce the speed of the classifier, and after the mill pressure difference returns to normal, increase the speed of the classifier to the normal value.

[0032] When the internal pressure difference exceeds a first pressure difference threshold, or when the internal pressure difference exceeds but is less than a second pressure difference threshold, the internal pressure difference is controlled by adjusting the feed rate, wherein the second pressure difference threshold is less than the first pressure difference threshold.

[0033] Optionally, controlling the classifier speed, the main roller pressure, and the feed rate through the mill vibration value includes:

[0034] When the mill vibration value exceeds a first vibration threshold, the feed rate is reduced, and / or the classifier speed and the main roller pressure are reduced.

[0035] In another aspect, the present invention provides a method for controlling a slag vertical mill, wherein the above-mentioned slag vertical mill control system comprises at least:

[0036] Determine whether there is at least one abnormal value among the collected feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current and main exhaust fan current;

[0037] If there are no abnormal values ​​among the collected data on feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current, and main exhaust fan current, or if there are abnormal values ​​but they are within a controllable range...

[0038] Control is achieved through the main motor current control circuit, mill outlet temperature control circuit, mill internal ventilation control circuit, and vibration control circuit, including:

[0039] The main motor current control circuit controls the main roller pressure, the target temperature inside the mill, and the feed rate through the main motor current.

[0040] The mill outlet temperature control loop corrects the target temperature inside the mill by the deviation of the main motor current, thereby controlling the mill outlet temperature.

[0041] The mill internal ventilation control circuit is used to control the classifier speed, the main exhaust fan speed, and the feed rate by means of the mill internal pressure difference and the main exhaust fan current;

[0042] The vibration control circuit is used to control the classifier speed, the main roller pressure, and the feed rate by the mill vibration value.

[0043] Optionally, the main motor current control circuit controls the main roller pressure, the target temperature inside the mill, and the feed rate through the main motor current, including:

[0044] When the main motor current is detected to exceed the rated power, the main roller pressure is reduced, and / or the feed rate is reduced;

[0045] The target temperature inside the mill is controlled by the average value of the main motor current and the direction of change of the main motor current to achieve a faster response, and the feed rate is balanced for control.

[0046] And / or,

[0047] The mill internal ventilation control circuit is used to control the classifier speed, the main exhaust fan speed, and the feed rate through the mill internal pressure difference and the main exhaust fan current, including:

[0048] When the internal pressure difference in the mill exceeds a first pressure difference threshold and the current of the main exhaust fan is less than a first current threshold.

[0049] Reduce the speed of the classifier, and after the pressure difference of the mill returns to normal, increase the speed of the classifier to the normal value;

[0050] When the internal pressure difference exceeds a first pressure difference threshold, or when the internal pressure difference exceeds but is less than a second pressure difference threshold, the internal pressure difference is controlled by adjusting the feed rate, wherein the second pressure difference threshold is less than the first pressure difference threshold.

[0051] And / or,

[0052] Controlling the classifier speed, the main roller pressure, and the feed rate by the mill vibration value includes:

[0053] When the mill vibration value exceeds a first vibration threshold, the feed rate is reduced, and / or the classifier speed and the main roller pressure are reduced.

[0054] Optionally, the mill outlet temperature is controlled by correcting the target temperature inside the mill through the deviation of the main motor current, including:

[0055] Feedforward control is achieved by controlling the target temperature inside the mill through the main motor current.

[0056] The mill outlet temperature is controlled by the change direction of the main motor current and the temperature deviation feedback between the target temperature inside the mill and the mill outlet temperature after feedforward correction.

[0057] As can be seen from the above solutions, the advantages of the present invention are:

[0058] The slag vertical mill control system provided by this invention includes a vertical mill operating condition parameter acquisition and judgment loop, a main motor current control loop, a mill outlet temperature control loop, a mill internal ventilation volume control loop, and a vibration control loop. The vertical mill operating condition parameter acquisition and judgment loop is used to determine whether at least one of the acquired parameters—feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current, and main exhaust fan current—is abnormal. The main motor current control loop controls the main roller pressure, mill target temperature, and feed rate through the main motor current. The mill outlet temperature control loop corrects the mill target temperature by adjusting the deviation of the main motor current, thereby controlling the mill outlet temperature. The mill internal ventilation volume control loop controls the classifier speed, main exhaust fan speed, and feed rate through the mill internal pressure difference and the main exhaust fan current. The vibration control loop controls the classifier speed, main roller pressure, and feed rate through the mill vibration value. This system can greatly reduce labor intensity, while timely adjusting and stabilizing mill operating conditions to ensure smooth and stable mill operation. Through production process modeling, it improves the automation level of the powder making process and effectively supports the construction of a smart slag factory. Attached Figure Description

[0059] Figure 1 This is an architecture diagram of a slag vertical mill control system based on existing technology.

[0060] Figure 2 This is a schematic diagram of the slag vertical mill control system of the present invention;

[0061] Figure 3 for Figure 2Schematic diagram of the main motor current control circuit;

[0062] Figure 4 for Figure 2 Schematic diagram of the temperature control loop at the outlet of the mill;

[0063] Figure 5 for Figure 2 Schematic diagram of the ventilation control loop inside the intermediate mill;

[0064] Figure 6 for Figure 2 A schematic diagram of the vibration control loop.

[0065] Figure 7 This is a schematic flowchart of the slag vertical mill control method of the present invention. Detailed Implementation

[0066] To make the above features and effects of the present invention clearer and easier to understand, specific embodiments are described below, and detailed descriptions are provided in conjunction with the accompanying drawings.

[0067] This application is aimed at Figure 1 The system has been improved as follows: 1) The material layer thickness control loop has been improved by using a main motor current control loop. Stable main motor current control ensures stable material layer thickness. 2) An internal mill ventilation control loop and a vibration control loop have been added to the control loop. 3) Monitoring of main motor current and main exhaust fan current has been added to the acquired variables. Main roller pressure, circulating air valve, exhaust gas valve, and main exhaust fan speed have been added to the control variables, covering all main control parameters during the one-button grinding process. Specifically:

[0068] This invention provides a slag vertical mill control system, specifically, as follows: Figure 2 As shown, Figure 1 The overall system architecture diagram of the slag vertical mill control system is shown.

[0069] A slag vertical mill control system, specifically comprising:

[0070] A vertical mill operating parameter acquisition and judgment loop is used to determine whether there is at least one abnormal value among the collected feed rate, mill vibration value, mill inlet temperature, mill outlet temperature, mill internal pressure difference, main motor current and main exhaust fan current.

[0071] A main motor current control circuit is connected to the vertical mill operating condition parameter acquisition and judgment circuit. The main motor current control circuit is used to control the main roller pressure, the target temperature inside the mill, and the feed rate through the main motor current.

[0072] A mill outlet temperature control loop is connected to the vertical mill operating condition parameter acquisition and judgment loop and the main motor current control loop. The mill outlet temperature control loop is used to correct the target temperature inside the mill by the deviation of the main motor current and control the mill outlet temperature.

[0073] A mill internal ventilation control circuit is connected to the vertical mill operating condition parameter acquisition and judgment circuit. The mill internal ventilation control circuit is used to control the classifier speed, the main exhaust fan speed, and the feed rate through the mill internal pressure difference and the main exhaust fan current.

[0074] A vibration control circuit is connected to the vertical mill operating condition parameter acquisition and judgment circuit. The vibration control circuit is used to control the classifier speed, the main roller pressure, and the feed rate through the mill vibration value.

[0075] In this embodiment, in specific implementation, for the main motor current control circuit, such as Figure 3 As shown, the main motor current is one of the important parameters reflecting the mill load. The main motor current control loop is divided into two models: the first is the main motor power protection control model, and the second is the motor current target control model.

[0076] When the mill is operating at full load, the main motor current frequently exceeds the rated power. To protect the main motor from overload burnout, a main motor power protection control model is designed. Its input data is the main motor current, and its output data are the feed rate and the main roller pressure. The motor power protection prioritizes rapid response. When the main motor current is detected to exceed the rated power, the main motor power protection control model controls the operation by reducing the main roller pressure and, consequently, reducing the feed rate.

[0077] To ensure stable grinding conditions, a target control model for motor current is designed, using the main motor current as one of the monitored variables. Main motor current stability is considered a prerequisite for stable grinding conditions. The input data is the main motor current, and the output data are the feed rate and the target temperature inside the mill. This target control model uses the average value of the main motor current and the direction of its change to control the target temperature inside the mill for a relatively rapid response, while also assisting in the balanced control of the feed rate.

[0078] In this embodiment, for the mill outlet temperature control loop, such as Figure 4As shown in the diagram. Temperature control is the core of mill control. Instability of the mill's internal temperature directly leads to instability of the mill's condition. The main source of mill temperature instability is the change in the moisture content of the incoming material: increased moisture causes suspended matter to settle inside the mill, and the denser material on the grinding disc leads to a rapid increase in the main motor current; decreased moisture causes the material to remain suspended, the material layer to become thinner, making it difficult to form a stable material bed buffer zone, resulting in over-grinding and vibration. In this embodiment, the outlet temperature control loop is configured to include two parts: a target temperature correction model and a temperature control model. The target temperature correction model, as a feedforward control, is configured to use the main motor current as input data and control the target temperature inside the mill through the main motor current. The temperature control model, connected to the target temperature correction model, is configured to use the main motor current and the temperature deviation between the feedforward-corrected target temperature inside the mill and the mill outlet temperature as input data and control the mill outlet temperature through the direction of change of the main motor current and the temperature deviation feedback.

[0079] Furthermore, in this embodiment, the temperature control model uses a fuzzy controller, outputting the mill outlet temperature, which is ultimately converted into an exhaust regulating unit for execution. The exhaust regulating unit is connected to the mill outlet temperature control loop and is used to regulate the mill outlet temperature. Specifically, the exhaust regulating unit includes: a circulating air valve, a hot blast stove gas valve, a cold air valve, and a waste gas discharge valve; wherein the circulating air valve and the hot blast stove gas valve have the highest priority; the cold air valve and the waste gas discharge valve have the next highest priority.

[0080] In this embodiment, for the mill internal ventilation control loop, such as Figure 5 As shown in the diagram. The airflow needs to match the feed rate. During production, the airflow and velocity inside the mill should be kept stable. Mill ventilation has a significant impact on the stability, quality, high output, and low consumption of the vertical mill. If the mill ventilation is insufficient, the material cannot be pulled out; if the ventilation is excessive, the fineness will easily become coarse, and the circulating fan current will be high, increasing the system power consumption. The variable should not be too large during adjustment. In the absence of airflow detection, the airflow = (power * 3600 * fan efficiency * mechanical transmission efficiency * 1000) / air pressure, where power = voltage * current. Therefore, if... Figure 5As shown, the mill's internal ventilation control loop is equipped with an airflow control model. The input data includes the mill's internal pressure difference and the main exhaust fan current. The output data includes the classifier speed, the main exhaust fan speed, and the feed rate. Specifically, the main exhaust fan current indirectly reflects the system's ventilation volume; a stable current indicates a stable airflow. The mill's internal pressure difference also indirectly reflects changes in the system's airflow, reflecting the amount of suspended material inside the mill. When the internal pressure difference increases, under full-grind conditions, ventilation is obstructed, and the airflow decreases. When the internal pressure difference decreases, the airflow increases. When the internal pressure difference of the mill increases and the current of the main exhaust fan decreases, it indicates that the mill is overloaded, the mill vibration is intensified, and the mill is unstable. At this time, the speed of the classifier should be reduced significantly to release the material immediately. After the mill pressure difference returns to normal, the speed should be slowly increased to the normal value. That is, when the internal pressure difference of the mill exceeds a first pressure difference threshold and the current of the main exhaust fan is less than a first current threshold, the speed of the classifier should be reduced. After the mill pressure difference returns to normal, the speed of the classifier should be increased to the normal value.

[0081] On the other hand, it reflects the dynamic balance between the feed and the output material. When the pressure difference inside the mill increases, it indicates that the amount of material entering the mill is greater than the amount exiting the mill, and the internal circulation volume increases. At this time, it is advisable to consider appropriately reducing the feed. When the pressure difference inside the mill decreases, it indicates that the amount of material entering the mill is less than the amount exiting the mill, the internal circulation volume decreases, and the material layer thickness becomes thinner. The pressure difference is generally controlled within the range of 34 to 40 mbar. If the pressure difference exceeds this range, that is, when the pressure difference inside the mill exceeds a first pressure difference threshold or is more than or less than a second pressure difference threshold, the pressure difference inside the mill is controlled by adjusting the feed rate. The second pressure difference threshold is less than the first pressure difference threshold.

[0082] In this embodiment, for the vibration control loop, such as Figure 6 As shown in the diagram, the vibration control loop is equipped with a vibration control model. The input data is the mill vibration value, and the output data are the classifier speed, the main roller pressure, and the feed rate. Vibration reflects whether the mill is operating stably. The most common cause is excessive feed, leading to mill over-grinding and vibration. In this case, the feed rate should be reduced. When the vibration intensifies to the point of affecting the normal operation of the mill, a rapid response is made by reducing the classifier speed and the main roller pressure. That is, when the mill vibration value exceeds a first vibration threshold, the feed rate is reduced, and / or the classifier speed and the main roller pressure are reduced.

[0083] Table 1 shows a comparison of the hourly energy consumption and unit output consumption of the system in this application with those of manual control, as shown in Table 1:

[0084] Table 1 Comparison of hourly energy consumption and output per unit of slag vertical mill control system and manual control system.

[0085]

[0086] Practice has proven that the application of the intelligent control system of this slag vertical mill control system can reduce energy consumption per unit output, saving approximately 1.81% in electricity consumption and 1.87% in gas energy. At the same time, the control process is stable, reducing the reduction in feed rate caused by abnormal vibration, changes in material moisture and abrasion resistance, and effectively increasing hourly output.

[0087] In summary, the slag vertical mill control system provided in this application includes a vertical mill operating condition parameter acquisition and judgment loop, a main motor current control loop, a mill outlet temperature control loop, a mill internal ventilation volume control loop, and a vibration control loop. The vertical mill operating condition parameter acquisition and judgment loop is used to determine whether at least one of the acquired parameters—feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current, and main exhaust fan current—is abnormal. The main motor current control loop controls the main roller pressure, mill target temperature, and feed rate using the main motor current. The mill outlet temperature control loop corrects the mill target temperature by adjusting the deviation of the main motor current, thereby controlling the mill outlet temperature. The mill internal ventilation volume control loop controls the classifier speed, main exhaust fan speed, and feed rate using the mill internal pressure difference and the main exhaust fan current. The vibration control loop controls the classifier speed, main roller pressure, and feed rate using the mill vibration value. This system can greatly reduce labor intensity and adjust and stabilize mill conditions in a timely manner to ensure smooth mill operation. It has been tested and proven to be stable in the No. 1 vertical mill of a steel plant. The system has improved the automation level of the powder making process through production process modeling and effectively supported the construction of a smart slag factory.

[0088] Furthermore, based on the aforementioned slag vertical mill control system, this invention further provides a slag vertical mill control method, such as... Figure 7 As shown, Figure 7 A schematic flow diagram of the slag vertical mill control method is shown, which includes at least:

[0089] S1. Determine whether there is at least one abnormal value among the collected feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current and main exhaust fan current.

[0090] S2. If there are no abnormal values ​​among the collected feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current, and main exhaust fan current, or if there are abnormal values ​​but they are within a controllable range...

[0091] Control is achieved through the main motor current control circuit, mill outlet temperature control circuit, mill internal ventilation control circuit, and vibration control circuit, including:

[0092] S31, the main motor current control circuit controls the main roller pressure, the target temperature inside the mill, and the feed rate through the main motor current.

[0093] Specifically, when the main motor current is detected to exceed the rated power, the main roller pressure is reduced, and / or the feed rate is reduced;

[0094] The target temperature inside the mill is controlled by the average value of the main motor current and the direction of change of the main motor current to achieve a faster response, and the feed rate is balanced for control.

[0095] S32. The mill outlet temperature control circuit corrects the target temperature inside the mill by the deviation of the main motor current, and controls the mill outlet temperature.

[0096] Specifically, the target temperature inside the mill is controlled by the main motor current through feedforward control; the mill outlet temperature is controlled by the change direction of the main motor current and the temperature deviation feedback between the target temperature inside the mill after feedforward correction and the mill outlet temperature.

[0097] S33. The mill ventilation control circuit controls the classifier speed, the main exhaust fan speed, and the feed rate through the mill pressure difference and the main exhaust fan current.

[0098] Specifically, when the pressure difference inside the mill exceeds a first pressure difference threshold and the current of the main exhaust fan is less than a first current threshold, the speed of the classifier is reduced. After the pressure difference in the mill returns to normal, the speed of the classifier is increased to the normal value.

[0099] When the internal pressure difference exceeds a first pressure difference threshold, or when the internal pressure difference exceeds but is less than a second pressure difference threshold, the internal pressure difference is controlled by adjusting the feed rate, wherein the second pressure difference threshold is less than the first pressure difference threshold.

[0100] S34. The vibration control circuit controls the classifier speed, the main roller pressure, and the feed rate through the mill vibration value.

[0101] Specifically, when the mill vibration value exceeds a first vibration threshold, the feed rate is reduced, and / or the classifier speed and the main roller pressure are reduced.

[0102] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A control system for a slag vertical mill, characterized in that, include: A vertical mill operating parameter acquisition and judgment loop is used to determine whether there is at least one abnormal value among the collected feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current and main exhaust fan current. A main motor current control circuit is connected to the vertical mill operating condition parameter acquisition and judgment circuit. The main motor current control circuit is used to control the main roller pressure, the target temperature inside the mill, and the feed rate through the main motor current. The main motor current control circuit includes: A main motor power protection control model is configured such that the input data is the main motor current, and the output data is the feed rate and the main roller pressure. The main motor power protection control model is used to reduce the main roller pressure and / or reduce the feed rate when the main motor current exceeds the rated power. A motor current target control model is configured such that the input data is the main motor current, and the output data is the feed rate and the target temperature inside the mill. The motor current target control model is used to control the target temperature inside the mill to respond quickly by using the average value of the main motor current and the direction of change of the main motor current, and to assist in the balanced control of the feed rate. A mill outlet temperature control loop is connected to the vertical mill operating condition parameter acquisition and judgment loop and the main motor current control loop. The mill outlet temperature control loop is used to correct the target temperature inside the mill by the deviation of the main motor current, thereby controlling the mill outlet temperature. The mill outlet temperature control loop includes: A target temperature correction model is configured such that the input data is the main motor current, and the target temperature correction model is used to perform feedforward control by controlling the target temperature inside the mill through the main motor current. A temperature control model, connected to the target temperature correction model, is configured such that the input data is the main motor current and the temperature deviation between the target temperature inside the mill and the mill outlet temperature after feedforward correction. The temperature control model is used to control the mill outlet temperature by the direction of change of the main motor current and the temperature deviation feedback. A mill internal ventilation control circuit is connected to the vertical mill operating condition parameter acquisition and judgment circuit. This circuit controls the classifier speed, the main exhaust fan speed, and the feed rate based on the mill internal pressure difference and the main exhaust fan current. The circuit includes: When the pressure difference inside the mill exceeds a first pressure difference threshold and the current of the main exhaust fan is less than a first current threshold, the speed of the classifier is reduced. After the pressure difference in the mill returns to normal, the speed of the classifier is increased to the normal value. A vibration control circuit is connected to the vertical mill operating condition parameter acquisition and judgment circuit. The vibration control circuit is used to control the classifier speed, the main roller pressure, and the feed rate through the mill vibration value.

2. The slag vertical mill control system according to claim 1, characterized in that, The temperature control model uses a fuzzy controller.

3. The slag vertical mill control system according to claim 2, characterized in that, Also includes: An exhaust fan regulating unit, connected to the mill outlet temperature control circuit, is used to regulate the mill outlet temperature and includes: Circulating air valve Hot blast furnace gas valve Cold air valve, exhaust gas valve; Among them, the circulating air valve and the hot blast stove gas valve have the highest priority; The cold air valve and exhaust valve have the next highest priority.

4. The slag vertical mill control system according to claim 1, characterized in that, Controlling the classifier speed, the main roller pressure, and the feed rate by the mill vibration value includes: When the mill vibration value exceeds a first vibration threshold, the feed rate is reduced, and / or the classifier speed and the main roller pressure are reduced.

5. A method for controlling a slag vertical mill, employing the slag vertical mill control system according to any one of claims 1-4, comprising at least: Determine whether there is at least one abnormal value among the collected feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current and main exhaust fan current; If there are no abnormal values ​​among the collected data on feed rate, mill vibration value, mill outlet temperature, mill internal pressure difference, main motor current, and main exhaust fan current, or if there are abnormal values ​​but they are within a controllable range... Control is achieved through the main motor current control circuit, mill outlet temperature control circuit, mill internal ventilation control circuit, and vibration control circuit, including: The main motor current control circuit controls the main roller pressure, the target temperature inside the mill, and the feed rate through the main motor current, including: When the main motor current is detected to exceed the rated power, the main roller pressure is reduced, and / or the feed rate is reduced; The target temperature inside the mill is controlled by the average value of the main motor current and the direction of change of the main motor current to achieve a faster response, and the feed amount is balanced and controlled. The mill outlet temperature control loop corrects the target temperature inside the mill by adjusting the deviation of the main motor current, thereby controlling the mill outlet temperature. This includes: Feedforward control is achieved by controlling the target temperature inside the mill through the main motor current. The mill outlet temperature is controlled by feedback of the change direction of the main motor current and the temperature deviation between the target temperature inside the mill and the mill outlet temperature after feedforward correction. The mill internal ventilation control circuit is used to control the classifier speed, the main exhaust fan speed, and the feed rate through the mill internal pressure difference and the main exhaust fan current, including: When the pressure difference inside the mill exceeds a first pressure difference threshold and the current of the main exhaust fan is less than a first current threshold, the speed of the classifier is reduced. After the pressure difference in the mill returns to normal, the speed of the classifier is increased to the normal value. The vibration control circuit is used to control the classifier speed, the main roller pressure, and the feed rate by the mill vibration value.

6. The slag vertical mill control method according to claim 5, characterized in that, Controlling the classifier speed, the main roller pressure, and the feed rate by the mill vibration value includes: When the mill vibration value exceeds a first vibration threshold, the feed rate is reduced, and / or the classifier speed and the main roller pressure are reduced.

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