Electric furnace body monitoring closed-loop water distribution system and control method

Abstract

This application discloses a closed-loop water distribution system and control method for monitoring electric furnace bodies, relating to the field of industrial electric furnace water cooling technology. Addressing the problems of existing electric furnace water distributors—such as limited monitoring dimensions, inability to distinguish between instrument malfunctions and actual water circuit anomalies, inconvenient fault location, and crude cooling adjustment leading to erroneous shutdowns and low maintenance efficiency—this application deploys sensing elements along the entire path of the inlet main pipe, each independent cooling branch, and the return main pipe. A dual fault diagnosis mechanism is implemented through the PLC control layer, combining multi-physical quantity correlation trend analysis of branches with main pipe-branch balance verification to cross-locate faults, simultaneously achieving single-branch PID closed-loop water flow regulation and hierarchical interlocking protection. This application can distinguish between instrument malfunctions and actual water circuit anomalies, locate fault points, achieve dynamic matching of cooling water flow, reduce the probability of unnecessary shutdowns, and improve the operational stability and maintenance efficiency of the water cooling system.

Description

Technical Field

[0001] This application relates to the technical field of water cooling systems for industrial electric furnaces, and in particular to a closed-loop water distribution system and control method for monitoring the furnace body. Background Technology

[0002] Industrial electric furnaces are widely used in industries such as casting, metallurgy, and heat treatment. Components such as the furnace body's induction coils, upper and lower short-circuit rings, and magnetic yoke continuously generate heat during operation, requiring a water cooling system to remove this heat and maintain the equipment's normal operating temperature. The water distributor is a crucial device in the water cooling system, responsible for distributing cooling water and collecting return water; its operational stability directly affects the overall operational safety and service life of the electric furnace. With the increasing power of electric furnace equipment and the growing demand for continuous production, the requirements for water cooling systems in terms of operational status monitoring and fault response are also gradually increasing.

[0003] Existing electric furnace water distributors are mostly purely mechanical structures, possessing only basic water distribution and collection functions. Typically, monitoring sensors are installed only at the inlet and outlet mains to monitor the overall system temperature, pressure, and flow parameters. Some distributors have added sensors to branch lines, but these only provide independent display of parameters for a single branch. Protection logic is mostly limited to triggering audible and visual alarms and shutdown interlocks when a single parameter exceeds its limit. Control methods primarily rely on manual valve adjustment or open-loop control. When operational abnormalities occur, maintenance personnel must check each pipeline and instrument line to confirm the location and type of fault.

[0004] Existing monitoring and protection solutions cannot distinguish between sensor malfunctions and actual cooling water circuit anomalies. When a single sensor experiences drift or disconnection, it can easily trigger false alarms or even shutdown interlocks, increasing unnecessary production interruptions. Relying solely on main pipe parameters and independent monitoring of individual branches cannot quickly locate faulty branches, resulting in lengthy troubleshooting times and impacting equipment maintenance efficiency. Summary of the Invention

[0005] This application provides a closed-loop water distribution system and control method for monitoring electric furnace body. Its purpose is to solve the problems of existing electric furnace water distributor monitoring schemes that cannot distinguish between instrument failures and actual water circuit abnormalities, and that fault location is inconvenient. At the same time, it realizes closed-loop regulation of branch cooling water volume, thereby improving the operational stability and maintenance efficiency of the water cooling system.

[0006] To achieve the above objectives, this application adopts the following technical solution: In the first aspect, a closed-loop water distribution system for integrated monitoring of electric furnace body temperature, flow rate and pressure is provided, including an inlet water distribution and regulation system, a furnace body cooling load unit, a return water collection and monitoring system and a PLC control layer. The water inlet distribution and regulation system includes a main water inlet pipe monitoring unit and a water inlet distributor unit. The main water inlet pipe monitoring unit is connected to the water inlet distributor unit. The main water inlet pipe monitoring unit integrates a temperature sensor, a pressure sensor, and a flow sensor. The water inlet distributor unit is equipped with multiple independent water inlet branch pipes. Each water inlet branch pipe is independently equipped with a temperature sensor, a pressure sensor, a flow sensor, and an electric regulating valve. The furnace cooling load unit includes multiple independent cooling branches, which correspond to the upper and lower short-circuit rings of the electric furnace, the cooling points of the magnetic yoke, and the cooling branches of the furnace induction coil. The water inlet of each cooling branch is connected to the water inlet branch of the water inlet water dispenser unit, and there is no series connection between the cooling branches. The return water collection and monitoring system includes a return water main pipe monitoring unit and a return water distributor unit. The return water main pipe monitoring unit is connected to the return water distributor unit. The return water main pipe monitoring unit integrates a temperature sensor, a pressure sensor, and a flow sensor. The return water distributor unit is equipped with multiple independent return water branch pipes, and each return water branch pipe is independently equipped with a temperature sensor, a pressure sensor, and a flow sensor. The outlet of each cooling branch pipe is connected to the return water branch pipe of the return water distributor unit one by one. The PLC control layer includes a data acquisition and preprocessing unit, a PID closed-loop control unit, a sensor and actuator self-diagnosis unit, and a hierarchical interlocking protection unit. The signal outputs of all temperature, pressure, and flow sensors are connected to the data acquisition and preprocessing unit. The data acquisition and preprocessing unit is connected to the PID closed-loop control unit and the sensor and actuator self-diagnosis unit, respectively. The outputs of both the PID closed-loop control unit and the sensor and actuator self-diagnosis unit are connected to the hierarchical interlocking protection unit. The control output of the PID closed-loop control unit is connected to the electric regulating valves of each inlet branch pipe, forming a closed-loop control circuit. The interlocking output of the hierarchical interlocking protection unit is used to connect to the main operating system of the electric furnace.

[0007] In the above embodiments, this application deploys sensing elements along the entire path of the main inlet pipe, each inlet branch pipe, each return branch pipe, and the main return pipe, and combines them with the self-diagnosis and closed-loop regulation unit of the PLC control layer to realize the acquisition of parameters and fault identification of the entire water circuit, forming a closed-loop regulation link for branch flow, so that protection actions and cooling regulation are both executed based on reliable operating condition judgment.

[0008] Secondly, a closed-loop control method for integrated monitoring of water cooling in an electric furnace body is provided, comprising the water distribution system as described in the first aspect, and including the following steps: S1: Real-time acquisition of temperature, pressure, and flow operating parameters of the main inlet pipe, each inlet branch pipe, each return branch pipe, and the main return pipe; synchronous acquisition of actual opening feedback signals of the electric regulating valves of each branch pipe. S2: Perform fault diagnosis on the collected sensor data and actuator status, the fault diagnosis including: The first diagnostic mechanism performs correlation trend analysis on at least two different physical quantity sensors on the same branch. When the rate of change of the first physical quantity exceeds a preset reasonable threshold and the second physical quantity does not show a corresponding change that conforms to the physical law, it is determined to be an instrument malfunction. The second diagnostic mechanism sums up the flow rate and temperature difference parameters of all operating branches and performs dynamic material balance or heat balance verification with the measured values ​​of the corresponding parameters of the inlet or return water main. When the deviation between the summed value of the branch and the measured value of the main exceeds the preset tolerance, the specific faulty branch and fault type are located by combining the branch correlation trend analysis results. Based on the judgment results of the first and second diagnostic mechanisms, the instrument failure is distinguished from the actual working condition of the water circuit, and corresponding fault handling strategies are generated. S3: Using the temperature difference between the inlet and outlet water of a single branch, the flow rate of the branch, or the pressure of the branch as the control target, the PID calculation outputs the opening adjustment command to the electric regulating valve of the corresponding branch to adjust the water supply of each cooling branch. S4: Compare the collected waterway operating parameters with the preset protection threshold to determine the protection level corresponding to the current operating condition; S5: Based on the determined protection level, corresponding protection actions will be executed, including early warning prompts, audible and visual alarms, and shutdown of the main operating system of the electric furnace.

[0009] In the above embodiments, this application combines branch correlation trend analysis with two diagnostic mechanisms, namely main pipe and branch balance verification, to distinguish between instrument failure and actual water circuit abnormality, complete the location of the faulty branch, and perform graded protection and closed-loop flow regulation on this basis, so that the operation judgment and control logic of the water cooling system are more in line with the actual working conditions.

[0010] In some embodiments of this application, the correlation trend analysis of the first diagnostic mechanism in step S2 includes: Time series correlation analysis is performed on the temperature sensor and flow sensor on the same branch to calculate the ratio of temperature change rate ΔT / Δt to flow change rate ΔQ / Δt in real time. When the ratio exceeds the normal coupling range preset according to the electric furnace operating conditions and the duration exceeds the first confirmation time threshold, it is determined that the temperature sensor of the branch has a drift fault, or the flow sensor has a drift or jamming fault.

[0011] In the above embodiments, this application determines instrument faults by coupling and comparing temperature and flow rate change rates, identifies abnormal sensor data based on the physical laws of fluid heat transfer, improves the accuracy of single-branch instrument fault judgment, and reduces misjudgments.

[0012] In some embodiments of this application, the dynamic material balance verification and thermal balance verification of the second diagnostic mechanism in step S2 specifically include: Material balance verification: Sum the instantaneous inflow values ​​of all operating branches to obtain the total branch flow ΣQbranch, and compare it with the measured value of the total inflow flow Qtotal. When |ΣQbranch-Qtotal| / Qtotal > preset material tolerance rate, it is determined that there is an abnormality in the branch flow measurement or the total flow measurement. Heat balance verification: Calculate the sum of the products of the flow rate of each branch and the corresponding inlet and outlet water temperature difference Σ(Q_branch × ΔT_branch), and compare it with the calculated value of the inlet main pipe flow rate multiplied by the total system temperature difference Q_total_inlet × (T_total_return - T_total_inlet). When the absolute value of the deviation between the two is greater than the ratio of the total heat exchange of the system to the preset heat balance deviation rate, it is determined that there is an abnormality in the branch temperature measurement, branch flow measurement, or main pipe temperature measurement.

[0013] In the above embodiments, this application uses two verification methods, material balance and thermal balance, to verify the consistency of measurement data at the overall system level, providing a system-level judgment basis for fault location and supplementing the limitations of single-branch analysis.

[0014] In some embodiments of this application, step S2 combines the branch correlation trend analysis results to locate the specific faulty branch and fault type, using cross-validation logic: When the second diagnostic mechanism determines that there is a system-level deviation, and the first diagnostic mechanism of a certain branch simultaneously determines that there is an instrument fault in that branch, the branch is marked as a faulty branch, and the faulty sensor type is determined according to the attributes of the abnormal physical quantities in the correlation trend analysis. When the second diagnostic mechanism determines that there is a system-level deviation, but the first diagnostic mechanism of all branches does not give a fault determination of the instrument, the fault source is located as the inlet main pipe sensor or the return main pipe sensor, and a main pipe instrument maintenance prompt is issued.

[0015] In the above embodiments, this application can distinguish between branch instrument failures and main pipe instrument failures through cross-verification of branch-level diagnosis and system-level verification, thereby narrowing the scope of fault investigation and facilitating targeted handling by maintenance personnel.

[0016] In some embodiments of this application, the fault diagnosis described in step S2 further includes an actuator diagnosis sub-step: Real-time acquisition of opening feedback signals of each electric regulating valve, continuous comparison of the opening feedback signals with the opening command output by the PID closed-loop regulating unit, when the deviation value exceeds the preset dead zone and continues to exceed the second confirmation time threshold, further determination of whether the measured flow value of the corresponding branch changes with the opening command. If the measured flow rate does not change as expected with the opening command, the electric regulating valve is determined to have a jamming fault. If the measured flow rate changes normally with the opening command, it is determined that the valve opening feedback sensor is faulty.

[0017] In the above embodiments, this application extends the scope of fault diagnosis to electric regulating valves and opening feedback sensors, which can distinguish between valve body jamming and abnormal feedback signals, thus improving the identification dimensions of fault types.

[0018] In some embodiments of this application, when a jamming fault is determined in the electric regulating valve, the fault handling strategy includes: Switch the control mode of the branch corresponding to the stuck valve from PID automatic adjustment to manual locking mode, lock the valve at the current opening degree or the preset safe opening degree; at the same time, block the software signal path of the branch that triggers interlock shutdown due to abnormal flow or temperature difference, retain only the independent hardware protection loop based on the return water temperature exceeding the limit, and generate a valve maintenance work order prompt.

[0019] In the above embodiments, this application adopts a method of locking the opening degree and interlocking with the shielding software to deal with valve jamming failure, maintaining branch cooling operation while retaining hardware over-temperature protection, and reducing unnecessary machine downtime.

[0020] In some embodiments of this application, the fault handling strategy generated in step S2 further includes: When a single sensor fault is diagnosed, only the instrument fault alarm is triggered, the water circuit abnormal interlock shutdown signal triggered by the fault sensor data of that branch is blocked, and the branch switches to the derating control mode of the remaining effective parameters to maintain the normal operation of the system.

[0021] In the above embodiments, this application adopts a derating operation mode for single sensor failure, which only triggers the fault indication and does not trigger the water circuit interlock shutdown, thereby reducing the probability of production interruption while ensuring basic cooling safety.

[0022] In some embodiments of this application, in step S3, when the electric furnace load increases and the return water temperature of a single branch rises, the PID closed-loop control unit increases the opening of the corresponding branch electric control valve to increase the cooling water flow; when the return water temperature is lower than the set value, the valve opening is reduced to achieve balanced cooling of the furnace body and energy-saving operation.

[0023] In the above embodiments, this application dynamically adjusts the valve opening according to the return water temperature to match the cooling requirements of the electric furnace under different loads, so that the cooling water volume of each branch can be dynamically adjusted according to the operating conditions.

[0024] In some embodiments of this application, a data storage and uploading step is also included: all operating parameters, fault records and protection action logs are synchronously stored in a historical database and can be uploaded to the factory DCS, MES or SCADA system via remote communication.

[0025] The above embodiments also include a data storage and uploading step: all operating parameters, fault records and protection action logs are synchronously stored in a historical database and can be uploaded to the factory DCS, MES or SCADA system via remote communication.

[0026] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0027] Figure 1 This is a structural block diagram of a closed-loop water distribution system for monitoring the furnace body of an electric furnace, as described in this application. Figure 2 This is a flowchart of a closed-loop water distribution system control method for monitoring an electric furnace body, as described in this application. Figure 3 This is a flowchart of the first diagnostic mechanism of the closed-loop water distribution system control method for monitoring electric furnace body according to this application; Figure 4 This is a flowchart of the second diagnostic mechanism of the closed-loop water distribution system control method for monitoring electric furnace body according to this application. Detailed Implementation

[0028] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0029] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0030] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0031] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0032] Additionally, if the meaning of "and / or" in the text is that it includes three parallel options, taking "A and / or B" as an example, it includes option A, option B, or an option that satisfies both A and B.

[0033] The present application will now be described in detail through exemplary embodiments. However, it should be understood that, without further description, elements, structures, and features in one embodiment may be advantageously incorporated into other embodiments.

[0034] It should be noted that industrial electric furnaces are widely used in industries such as casting, metallurgy, and heat treatment. Components such as the furnace body's induction coils, upper and lower short-circuit rings, and magnetic yoke continuously generate heat during operation, which must be removed by a water cooling system to maintain the equipment's normal operating temperature. The water distributor is a key device in the water cooling system responsible for distributing cooling water and collecting return water; its operational stability directly affects the overall operational safety and service life of the electric furnace. With the increasing power of electric furnace equipment and the growing demand for continuous production, the requirements for water cooling systems in terms of operational status monitoring and fault response are also gradually increasing.

[0035] Existing electric furnace water distributors are mostly purely mechanical structures, possessing only basic water distribution and collection functions. Typically, monitoring sensors are installed only at the inlet and outlet mains to monitor the overall system temperature, pressure, and flow parameters. Some distributors have added sensors to branch lines, but these only provide independent display of parameters for a single branch. Protection logic is mostly limited to triggering audible and visual alarms and shutdown interlocks when a single parameter exceeds its limit. Control methods primarily rely on manual valve adjustment or open-loop control. When operational abnormalities occur, maintenance personnel must check each pipeline and instrument line to confirm the location and type of fault.

[0036] Existing monitoring and protection solutions cannot distinguish between sensor malfunctions and actual cooling water circuit anomalies. When a single sensor experiences drift or disconnection, it can easily trigger false alarms or even shutdown interlocks, increasing unnecessary production interruptions. Relying solely on main pipe parameters and independent monitoring of individual branches cannot quickly locate faulty branches, resulting in lengthy troubleshooting times and impacting equipment maintenance efficiency.

[0037] Based on this, this application proposes an integrated monitoring closed-loop water distribution system for electric furnace body temperature, flow rate, and pressure, and an integrated monitoring closed-loop control method for water cooling. By deploying temperature, pressure, and flow sensors along the entire path of the inlet main pipe, each independent cooling branch, and the return main pipe, and combining the dual fault diagnosis logic of multi-physical quantity correlation trend diagnosis of the branches and material balance and heat balance verification of the main pipe and branches, and through the PID closed-loop regulation and hierarchical interlocking protection mechanism of the single-branch electric regulating valve, the system can distinguish between instrument faults and actual water circuit anomalies, locate faulty branches, and dynamically adjust the cooling water volume. This solves the problems of existing electric furnace water distributor monitoring schemes that are prone to triggering false alarms and false shutdowns, have long fault troubleshooting cycles, and use crude cooling adjustment methods.

[0038] In the following, embodiments of this application will be described in detail with reference to the accompanying drawings.

[0039] As attached Figure 1 As shown in an illustrative embodiment of this application, in a first aspect, an integrated monitoring closed-loop water distribution system for electric furnace body temperature, flow rate, and pressure is provided, including an inlet water distribution and regulation system, a furnace body cooling load unit, a return water collection and monitoring system, and a PLC control layer.

[0040] The water inlet distribution and regulation system includes a main water inlet pipe monitoring unit and a water inlet distributor unit. The main water inlet pipe monitoring unit is connected to the water inlet distributor unit. The main water inlet pipe monitoring unit integrates a temperature sensor, a pressure sensor, and a flow sensor. The water inlet distributor unit is equipped with multiple independent water inlet branch pipes. Each water inlet branch pipe is independently equipped with a temperature sensor, a pressure sensor, a flow sensor, and an electric regulating valve. The furnace cooling load unit includes multiple independent cooling branches, which correspond to the upper and lower short-circuit rings of the electric furnace, the cooling points of the magnetic yoke, and the cooling branches of the furnace induction coil. The water inlet of each cooling branch is connected to the water inlet branch of the water inlet water dispenser unit, and there is no series connection between the cooling branches. The return water collection and monitoring system includes a return water main pipe monitoring unit and a return water distributor unit. The return water main pipe monitoring unit is connected to the return water distributor unit. The return water main pipe monitoring unit integrates a temperature sensor, a pressure sensor, and a flow sensor. The return water distributor unit is equipped with multiple independent return water branch pipes, and each return water branch pipe is independently equipped with a temperature sensor, a pressure sensor, and a flow sensor. The outlet of each cooling branch pipe is connected to the return water branch pipe of the return water distributor unit one by one. The PLC control layer includes a data acquisition and preprocessing unit, a PID closed-loop control unit, a sensor and actuator self-diagnosis unit, and a hierarchical interlocking protection unit. The signal outputs of all temperature, pressure, and flow sensors are connected to the data acquisition and preprocessing unit. The data acquisition and preprocessing unit is connected to the PID closed-loop control unit and the sensor and actuator self-diagnosis unit, respectively. The outputs of both the PID closed-loop control unit and the sensor and actuator self-diagnosis unit are connected to the hierarchical interlocking protection unit. The control output of the PID closed-loop control unit is connected to the electric regulating valves of each inlet branch pipe, forming a closed-loop control circuit. The interlocking output of the hierarchical interlocking protection unit is used to connect to the main operating system of the electric furnace.

[0041] This application deploys sensing elements along the entire path of the main inlet pipe, each inlet branch pipe, each return branch pipe, and the main return pipe. Combined with the self-diagnosis and closed-loop regulation unit of the PLC control layer, it realizes the acquisition of water circuit parameters and fault identification, so that protection actions and cooling regulation are all based on reliable operating condition judgments.

[0042] Specifically, the water inlet distribution and regulation system, serving as the inlet distribution terminal for cooling water, sequentially includes an inlet main pipe monitoring unit and an inlet water distributor unit along the water flow direction. The inlet main pipe monitoring unit is connected in series between the external water supply pipeline and the inlet water distributor, integrating three types of detection elements: temperature sensor, pressure sensor, and flow sensor. It can acquire the basic operating parameters of the total system water intake in real time, providing benchmark data for subsequent balance verification.

[0043] Furthermore, the inlet water distribution unit adopts an integrated water distribution chamber structure, which evenly distributes the single water flow of the main inlet pipe into multiple independent inlet branches. Each inlet branch is independently equipped with a temperature sensor, a pressure sensor, a flow sensor, and an electric regulating valve. The sensing elements are responsible for collecting real-time parameters of the inlet side of a single branch, and the electric regulating valve, as the actuator, receives control commands and precisely adjusts the cooling water flow of the corresponding branch, thereby realizing independent water distribution control of a single branch.

[0044] In some embodiments, the furnace cooling load unit corresponds to all the heating components of the furnace body and includes multiple independent cooling branches, which respectively correspond to the upper and lower short-circuit rings of the furnace, the cooling points of the magnetic yoke, and the cooling branch of the furnace induction coil. The water inlet of each cooling branch is connected to the water inlet branch of the water inlet water dispenser unit, and each cooling branch is independent of each other and not connected in series.

[0045] Furthermore, by adopting an independent branch cooling method, it can be ensured that the water entering each cooling point is low-temperature cooling water of the same temperature, avoiding the problem of the water temperature rising after the preceding points absorb heat and causing the cooling capacity of the subsequent points to decrease when cooling is connected in series. At the same time, the operating parameters of each branch can correspond to a cooling point, which makes it easy to accurately locate the furnace body components with abnormal heating.

[0046] Specifically, the return water collection and monitoring system is symmetrically arranged on the inlet side, with return water distributor units and return water main monitoring units sequentially arranged along the water flow direction. Each return water distributor unit has multiple independent return water branch pipes, each equipped with an independent temperature sensor, pressure sensor, and flow sensor. The outlet of each cooling branch is connected to the return water branch pipe of the return water distributor unit, allowing for individual collection of return water parameters at each cooling point. Furthermore, the water flow from all return water branch pipes converges into the main chamber of the return water distributor before flowing into the return water main monitoring unit. This unit also integrates temperature, pressure, and flow sensors to collect the overall return water operating data. Combined with the baseline data from the inlet main pipe, the total heat exchange and total pressure drop of the entire water cooling system can be calculated, reflecting the overall cooling operation status of the system.

[0047] In some embodiments, the PLC control layer includes four functional modules: a data acquisition and preprocessing unit, a PID closed-loop regulation unit, a sensor and actuator self-diagnosis unit, and a hierarchical interlocking protection unit. The signal output terminals of all temperature sensors, pressure sensors, and flow sensors are connected to the data acquisition and preprocessing unit, which performs analog signal acquisition, analog-to-digital conversion, engineering value conversion, and filtering to output stable and effective operating parameters.

[0048] Furthermore, the data acquisition and preprocessing unit is connected to the PID closed-loop control unit and the sensor and actuator self-diagnosis unit respectively, and simultaneously transmits the processed operating parameters to the PID closed-loop control unit and the sensor and actuator self-diagnosis unit; the PID closed-loop control unit calculates the valve control command based on the inlet and outlet water parameters of the branch, and the sensor and actuator self-diagnosis unit completes fault identification and location based on the parameter coupling relationship of the whole path.

[0049] Furthermore, the outputs of both the PID closed-loop control unit and the sensor and actuator self-diagnostic unit are connected to a tiered interlocking protection unit. This unit combines real-time operating data with fault diagnosis results to comprehensively determine the system's safety level, preventing false protection actions caused by instrument malfunctions. The control output of the PID closed-loop control unit is directly connected to the electric regulating valves of each inlet branch pipe, forming a complete closed-loop control circuit with the valve opening feedback signal, achieving dynamic and precise regulation of the cooling water volume. The interlocking output of the tiered interlocking protection unit is connected to the electric furnace's main operating system, directly triggering the furnace shutdown protection when a serious water circuit abnormality is detected, preventing overheating damage to furnace components.

[0050] Overall, the full-path sensing layout provides a complete data foundation for fault diagnosis and closed-loop regulation. The self-diagnostic unit ensures the accuracy of operating condition judgment, the closed-loop regulation unit realizes dynamic matching of cooling water volume on demand, and the hierarchical interlocking protection unit takes into account both operational safety and production continuity. All modules work together to improve the operational reliability and maintenance efficiency of the electric furnace water cooling system.

[0051] Secondly, a closed-loop control method for integrated monitoring of water cooling in an electric furnace body is provided, including the water distribution system as described in the first aspect, such as... Figure 2 As shown, it includes the following steps: S1: Real-time acquisition of temperature, pressure, and flow operating parameters of the main inlet pipe, each inlet branch pipe, each return branch pipe, and the main return pipe; synchronous acquisition of actual opening feedback signals of the electric regulating valves of each branch pipe. Specifically, step S1 provides a complete data foundation for the entire control method. The data acquisition range covers all water circuit nodes, including the main inlet pipe, all inlet branch pipes, all return branch pipes, and the main return pipe. It can acquire the inlet and return parameters of each cooling point and simultaneously acquire the actual opening feedback signal of the electric regulating valve to ensure that the timestamps of the sensor data and the actuator status data are consistent, providing synchronous data support for subsequent coupling analysis and closed-loop control.

[0052] In some embodiments, the acquired raw signal is first processed by filtering and engineering value conversion to filter out instantaneous data jumps caused by electromagnetic interference at the scene, convert the analog signal into a value in the corresponding physical unit, and then input it into the subsequent calculation and diagnostic modules to ensure the accuracy of subsequent judgments.

[0053] S2: Perform fault diagnosis on the collected sensor data and actuator status, the fault diagnosis including: like Figure 3 As shown, the first diagnostic mechanism performs correlation trend analysis on at least two different physical quantity sensors on the same branch. When the rate of change of the first physical quantity exceeds a preset reasonable threshold and the second physical quantity does not show a corresponding change that conforms to the physical law, it is determined to be an instrument malfunction. like Figure 4 As shown, the second diagnostic mechanism sums the flow rate and temperature difference parameters of all operating branches and performs dynamic material balance or heat balance verification with the measured values ​​of the corresponding parameters of the inlet or return water main. When the deviation between the summed value of the branch and the measured value of the main exceeds the preset tolerance, the specific faulty branch and fault type are located by combining the branch correlation trend analysis results. By combining the results of the first and second diagnostic mechanisms, the system distinguishes between instrument malfunctions and actual water circuit conditions, and generates corresponding fault handling strategies. Specifically, step S2 achieves accurate fault identification and location through two complementary diagnostic mechanisms, cross-verifying the operating condition from both individual branch and system-wide dimensions. The first diagnostic mechanism uses the coupling relationship of multiple physical quantities within a branch to initially determine a single branch fault. Under normal operating conditions, physical quantities such as temperature, flow rate, and pressure in the same cooling branch follow the basic laws of fluid heat transfer and exhibit clear corresponding changes. For example, when the branch flow rate increases, the heat transfer capacity improves, and the return water temperature will simultaneously show a decreasing trend, with the change rates of the two types of physical quantities maintaining a stable proportional range. When the change rate of one physical quantity exceeds a preset reasonable threshold, while the other physical quantity does not show a corresponding change in accordance with the law, it indicates that the sensor data does not conform to the true physical logic, and an instrument fault can be determined. The correlation trend analysis continuously monitors the duration of the abnormal state, and only outputs the fault determination result when the abnormal state exceeds the set confirmation time, which can filter out misjudgments caused by instantaneous data fluctuations and improve the reliability of the diagnostic results.

[0054] Specifically, the second diagnostic mechanism verifies data consistency at the system-wide level through two types of checks: material balance and thermal balance. Material balance verification is based on the principle of fluid continuity; under normal operating conditions, the deviation between the sum of flow rates of all operating branches and the measured flow rate of the main pipe should be within the allowable range of measurement error. Thermal balance verification is based on the principle of energy conservation; similarly, the deviation between the sum of heat exchange of all branches and the total heat exchange of the system should be within a reasonable range. When the deviation between the sum of branch values ​​and the measured value of the main pipe exceeds the preset tolerance, it indicates a measurement anomaly within the system. In this case, combined with the branch-level analysis results of the first diagnostic mechanism, the specific faulty branch and fault type can be located. Furthermore, if there is a deviation in the system-level verification, but no anomalies are detected in the individual branch diagnoses of all branches, the fault can be determined to originate from the sensing element on the main pipe side. This distinguishes between branch faults and main pipe faults, narrowing the scope of fault investigation.

[0055] Furthermore, by combining the results of the two diagnostic mechanisms, the system can clearly distinguish between instrument malfunctions and actual cooling water circuit anomalies, and generate corresponding handling strategies for different fault types. This avoids misjudging instrument malfunctions as cooling water circuit anomalies and triggering unnecessary shutdown protection, thereby improving the continuity of production operations while ensuring equipment safety.

[0056] S3: Using the temperature difference between the inlet and outlet water of a single branch, the flow rate of the branch, or the pressure of the branch as the control target, the PID calculation outputs the opening adjustment command to the electric regulating valve of the corresponding branch to adjust the water supply of each cooling branch. Specifically, step S3 dynamically adjusts the water volume of each cooling branch. A PID control logic runs independently for each branch, adjusting the opening of the electric regulating valve in real time based on the branch's actual operating parameters to match the current heat load. The control target can be flexibly selected according to actual production needs. Using the inlet and outlet water temperature difference as the control target ensures stable heat exchange efficiency at each cooling point; using the branch flow rate as the control target ensures constant cooling water volume in each branch; and using the branch pressure as the control target maintains stable pipeline pressure, preventing pressure fluctuations from damaging cooling components.

[0057] Furthermore, after the opening command output by the PID regulator is sent to the electric regulating valve, it will be combined with the opening feedback signal collected in step S1 to form a closed-loop verification, confirming that the valve is executed in place, ensuring the accuracy of the regulation action, and forming a complete closed-loop control link.

[0058] S4: Compare the collected waterway operating parameters with the preset protection threshold to determine the protection level corresponding to the current operating condition; S5: Based on the determined protection level, corresponding protection actions will be executed, including early warning prompts, audible and visual alarms, and shutdown of the main operating system of the electric furnace.

[0059] Specifically, steps S4 and S5 together constitute a tiered protection logic, comparing water circuit operating parameters with multi-level preset thresholds to match the corresponding protection level. The tiered thresholds cover different operating conditions, from minor anomalies to severe hazards, corresponding to protection actions of varying intensities. Furthermore, the protection level determination is combined with the fault diagnosis results from step S2. If the abnormal parameters originate from instrument malfunctions, high-level shutdown protection will not be triggered; only an instrument maintenance prompt will be output. Only when a genuine water circuit anomaly is determined and the parameters reach the corresponding thresholds will warning, alarm, and shutdown actions be triggered at each level. This tiered and interconnected protection method can promptly alert maintenance personnel when operating conditions are abnormal, reliably protect equipment in hazardous conditions, and avoid unnecessary production interruptions caused by instrument malfunctions.

[0060] In the above scheme, this application combines two diagnostic mechanisms, namely branch correlation trend analysis and main pipe and branch balance verification, to distinguish between instrument failure and actual water circuit abnormality, complete the location of the faulty branch, and on this basis, perform graded protection and closed-loop flow regulation, so that the operation judgment and control logic of the water cooling system are more in line with the actual working conditions.

[0061] In some embodiments, the correlation trend analysis of the first diagnostic mechanism in step S2 includes: Time series correlation analysis is performed on the temperature sensor and flow sensor on the same branch to calculate the ratio of temperature change rate ΔT / Δt to flow change rate ΔQ / Δt in real time. When the ratio exceeds the normal coupling range preset according to the electric furnace operating conditions and the duration exceeds the first confirmation time threshold, it is determined that the temperature sensor of the branch has a drift fault, or the flow sensor has a drift or jamming fault.

[0062] It should be noted that a jamming fault describes a complete failure state where the parts are completely stuck and unable to move. The moving parts are directly jammed by foreign objects or deformed structures, completely unable to respond to control commands, and remain in a fixed position without moving.

[0063] In the above scheme, this application judges instrument faults by coupling and comparing temperature and flow rate change rate, and identifies abnormal sensor data based on the physical laws of fluid heat transfer, thereby improving the accuracy of single-branch instrument fault judgment and reducing misjudgment.

[0064] Specifically, the correlation trend analysis selects two parameters—return water temperature and flow rate—on the same cooling branch as the analysis objects. These two parameters have a clear physical coupling relationship during forced convection heat transfer. Under normal operating conditions, changes in flow rate directly correspond to inverse changes in return water temperature, and the ratio of their changes remains relatively stable. The system reads real-time values ​​of temperature and flow rate at fixed sampling intervals, calculates the temperature change and flow rate change per unit time, and then obtains the coupling coefficient by comparing the two values, thereby quantifying the degree of matching between the changes of the two physical quantities.

[0065] Furthermore, the values ​​of the normal coupling range can be obtained through on-site calibration under the rated operating conditions of the electric furnace. Corresponding ranges can be set for branches with different power levels and cooling points to ensure that the judgment benchmark matches the actual operating conditions. When the coupling change coefficient exceeds the upper and lower limits of the normal coupling range, the system starts timing statistics. Only when the abnormal state is continuously maintained and the duration exceeds the first confirmation duration threshold will the final instrument fault judgment result be output. Setting the confirmation duration threshold can effectively filter out short-term data jumps caused by electromagnetic interference and instantaneous turbulence in industrial environments, avoid single abnormal sampling triggering incorrect diagnosis, and improve the anti-interference capability and reliability of the diagnostic results.

[0066] Specifically, based on the correspondence of abnormal parameters, the type and form of faulty sensors can be further distinguished. If the temperature change rate significantly deviates from the reasonable range, while the flow rate change rate remains within the normal fluctuation range, the temperature sensor in that branch is determined to have a drift fault, mostly caused by aging of the sensing element and increased temperature drift. If the flow rate change rate significantly deviates from the reasonable range, while the temperature change rate remains stable, the flow sensor in that branch is determined to have a drift or jamming fault. Jamming faults are common in impeller-type flow detection elements, mostly caused by scale buildup in the pipeline or small foreign objects obstructing impeller rotation. Through the coupling analysis of the change rate, no additional detection element is needed; fault identification and preliminary classification can be completed using only existing sensor data, without increasing the system hardware cost.

[0067] In some embodiments, the dynamic material balance verification and thermal balance verification of the second diagnostic mechanism in step S2 specifically include: Material balance verification: Sum the instantaneous inflow values ​​of all operating branches to obtain the total branch flow ΣQbranch, and compare it with the measured value of the total inflow in the main inlet pipe Qtotal. If |ΣQbranch - Qtotal| / Qtotal > the preset material tolerance rate, it is determined that there is an abnormality in the branch flow measurement or the main pipe flow measurement.

[0068] Heat balance verification: Calculate the sum of the products of the flow rate of each branch and the corresponding inlet and outlet water temperature difference Σ(Q_branch × ΔT_branch), and compare it with the calculated value of the inlet main pipe flow rate multiplied by the total system temperature difference Q_total_inlet × (T_total_return - T_total_inlet). When the absolute value of the deviation between the two is greater than the ratio of the total heat exchange of the system to the preset heat balance deviation rate, it is determined that there is an abnormality in the branch temperature measurement, branch flow measurement, or main pipe temperature measurement.

[0069] In the above scheme, this application uses two verification methods, material balance and thermal balance, to verify the consistency of measurement data at the overall system level, providing a system-level judgment basis for fault location and supplementing the limitations of single branch analysis.

[0070] Specifically, under normal operating conditions, cooling water is an incompressible fluid that satisfies the continuity equation during steady-state flow. The total flow rate at the main inlet pipe should equal the sum of the flow rates of all branches in operation. In actual calculations, the system synchronously collects the instantaneous flow rates of all inlet branches at the same time, sums the flow rates of each branch to obtain the total branch flow rate, and then compares it with the measured flow rate of the main inlet pipe. The absolute value of the difference is calculated as a percentage of the measured flow rate of the main pipe, thus obtaining the flow deviation rate. The preset material tolerance rate comprehensively considers the measurement accuracy errors of each sensor, the minor flow deviations caused by uneven pipeline resistance, and the synchronization errors of data sampling, and falls within the acceptable deviation range under normal operating conditions. When the calculated deviation rate exceeds the preset tolerance rate, it indicates an anomaly in the flow measurement data within the system. The source of the anomaly may be a failure of the flow sensor in a branch or a deviation in the flow sensor on the main pipe side, thus completing the initial judgment of system-level flow anomalies.

[0071] Furthermore, the heat balance verification is based on the principle of energy conservation and simultaneously covers the consistency verification of both flow rate and temperature parameters. Cooling water absorbs heat as it flows through the furnace cooling branches. The heat exchange of a single branch per unit time is proportional to the branch's cooling water flow rate and the temperature difference between the inlet and outlet water. The cumulative heat exchange value of all branches should be consistent with the total heat exchange of the entire system. In actual calculations, the flow rate of each operating branch is first calculated as the product of the corresponding inlet and outlet water temperature difference. The calculation results for all branches are then summed to obtain a reference value for the total heat exchange on the branch side. Next, the total heat exchange reference value on the main pipe side is calculated by multiplying the inlet main pipe flow rate by the system's total temperature difference, where the system's total temperature difference is the difference between the return main pipe temperature and the inlet main pipe temperature. Finally, the absolute value of the deviation between the two reference values ​​is calculated and compared with the total heat exchange reference value on the main pipe side to obtain the heat balance deviation rate. The preset thermal balance deviation rate also incorporates the measurement errors of both temperature and flow sensors. When the deviation rate exceeds the threshold, it indicates that there is an abnormality in the temperature or flow measurement within the system. The abnormality covers all temperature and flow detection elements on both the branch and main pipe sides.

[0072] Specifically, when only the material balance verification exceeds the standard, the anomaly can be initially identified as originating from the flow detection stage; when only the heat balance verification exceeds the standard, the anomaly can be initially identified as originating from the temperature detection stage; when both types of verifications exceed the standard simultaneously, further cross-location is required by combining the branch-level analysis results of the first diagnostic mechanism. Through global data verification of the main pipe and branches, the limitation of single-branch correlation analysis in identifying faults within branches can be overcome, enabling the identification and location of faults in sensing elements on the main pipe side. This allows the entire fault diagnosis system to cover all detection nodes, improving the comprehensiveness and accuracy of the overall judgment.

[0073] In some embodiments, step S2 combines the branch correlation trend analysis results to locate the specific faulty branch and fault type, using cross-validation logic: When the second diagnostic mechanism determines that there is a system-level deviation, and the first diagnostic mechanism of a certain branch simultaneously determines that there is an instrument fault in that branch, the branch is marked as a faulty branch, and the faulty sensor type is determined according to the attributes of the abnormal physical quantities in the correlation trend analysis.

[0074] When the second diagnostic mechanism determines that there is a system-level deviation, but the first diagnostic mechanism of all branches does not give a fault determination of the instrument, the fault source is located as the inlet main pipe sensor or the return main pipe sensor, and a main pipe instrument maintenance prompt is issued.

[0075] In the above solution, this application can distinguish between branch instrument failures and main pipe instrument failures through cross-verification of branch-level diagnosis and system-level verification, thus narrowing the scope of fault investigation and facilitating targeted handling by maintenance personnel.

[0076] Specifically, the cross-validation logic uses the system-level deviation judgment of the second diagnostic mechanism as the trigger condition, and combines it with the branch-level path-by-path detection results of the first diagnostic mechanism for bidirectional verification, thus solving the judgment blind spot problem existing in a single diagnostic mechanism. Relying solely on branch correlation trend analysis can only identify sensing anomalies within a single branch and cannot determine whether the main pipe-side detection element has failed; relying solely on system-level balance verification can only determine that there is an overall data deviation and cannot locate the specific faulty branch. After the two mechanisms are combined, the fault location can be accurately located, improving the reliability of the diagnostic results.

[0077] Furthermore, when the second diagnostic mechanism determines that the system has a measurement deviation, and the first diagnostic mechanism of a certain branch simultaneously outputs an instrument fault determination result, that branch can be directly marked as a faulty branch. At this time, the abnormal data on the branch side can precisely explain the source of the system-level deviation. The two types of determination results corroborate each other, and the accuracy of the fault determination is far higher than that of a single mechanism. At the same time, based on the abnormal physical quantity attributes identified in the branch correlation trend analysis, the specific type of faulty sensor can be directly determined. For example, an abnormal temperature corresponds to a temperature sensor fault, and an abnormal flow corresponds to a flow sensor fault. Maintenance personnel can directly repair or replace the corresponding components.

[0078] It should be noted that the system-level deviation is the judgment result output by the second diagnostic mechanism. It refers to the inconsistency between the measured data on the main pipe side and the calculated data after summing all branches from the global perspective of the entire water cooling system, which exceeds the normal measurement error range. It is used to determine that there is an anomaly in the overall measurement link of the system, rather than the normal operating condition fluctuation of a single branch.

[0079] The system-level deviation under material balance verification refers to the deviation rate exceeding the preset material tolerance rate when the sum of the inlet flow rates of all operating branches is compared with the measured flow rate of the main inlet pipe. Under normal operating conditions, the cooling water satisfies mass conservation, and the difference between the sum of the branch flow rates and the main pipe flow rate comes only from the accuracy error of the sensor itself, and the value is very small. When the deviation exceeds the tolerance range, it indicates that there is a contradiction in the global flow data, which must be due to an anomaly in the measurement of one or more flow sensors.

[0080] If the temperature or flow rate of a single branch exceeds the threshold, it may be due to a real water circuit anomaly (such as pipe blockage or increased load) or a sensor malfunction; however, if a system-level deviation occurs, it must be a problem in the measurement process, and it is the basis for distinguishing between instrument malfunction and real water circuit anomaly.

[0081] The system-level deviation under heat balance verification refers to the difference between the sum of the heat exchange of all operating branches (branch flow rate × branch inlet and outlet water temperature difference) and the total system heat exchange calculated from the main pipe side (main pipe flow rate × main pipe inlet and outlet water temperature difference), and the deviation rate exceeding the preset heat balance deviation rate. Under normal operating conditions, energy is conserved, and the two calculation results should be basically consistent; when an out-of-tolerance deviation occurs, it indicates that there is an overall inconsistency in the global temperature or flow measurement data, and that there is a fault in the measurement link.

[0082] Under normal operating conditions, the cooling water meets the law of conservation of mass, and the difference between the total flow rate of the branches and the flow rate of the main pipe comes only from the accuracy error of the sensor itself, and the value is very small. When the deviation exceeds the tolerance range, it indicates that there is a contradiction in the global flow data, and there must be an abnormality in the measurement of one or more flow sensors.

[0083] Specifically, when the second diagnostic mechanism determines that there is a system-level deviation, but the first diagnostic mechanism for all branches does not output any instrument fault determination results after checking each branch, the possibility of a faulty sensor on the branch side can be ruled out, and the fault source can be directly located as the inlet main pipe sensor or the return main pipe sensor. At this time, the system will simultaneously issue a main pipe instrument maintenance prompt, guiding maintenance personnel to prioritize checking the detection components at the main pipe, without needing to check each branch individually.

[0084] Furthermore, this hierarchical positioning logic does not require additional detection hardware. It can accurately locate fault points simply through logical operations on existing sensor data. It can distinguish between instrument faults and actual water circuit anomalies, and further distinguish between branch circuit faults and main pipe faults. This significantly reduces the time spent on troubleshooting, improves the operation and maintenance efficiency of the water cooling system, and also reduces the production downtime caused by the inability to quickly locate instrument faults.

[0085] In some embodiments, the fault diagnosis in step S2 further includes an actuator diagnosis sub-step: The opening feedback signals of each electric regulating valve are collected in real time. The opening feedback signals are continuously compared with the opening commands output by the PID closed-loop regulating unit. When the deviation value exceeds the preset dead zone and continues to exceed the second confirmation time threshold, it is further determined whether the measured flow value of the corresponding branch changes with the opening command.

[0086] If the measured flow rate does not change as expected with the opening command, the electric regulating valve is determined to have a jamming fault.

[0087] If the measured flow rate changes normally with the opening command, it is determined that the valve opening feedback sensor is faulty.

[0088] In the above solution, this application extends the scope of fault diagnosis to electric regulating valves and opening feedback sensors, which can distinguish between valve body jamming and abnormal feedback signals, and improve the identification dimensions of fault types.

[0089] Specifically, as the core actuator of closed-loop regulation, the operating status of the electric regulating valve directly affects the accuracy of cooling water flow regulation. Problems such as valve jamming and distorted feedback signals can lead to closed-loop regulation failure, resulting in abnormal temperature differences in the cooling branches. Relying solely on sensor correlation analysis can easily misdiagnose these as actual water circuit faults. Through specialized actuator diagnostic logic, the type of fault at the actuator end can be accurately identified, providing a basis for subsequent differentiated handling.

[0090] Furthermore, the diagnostic process begins by comparing the deviation between the command and the feedback. The system acquires the target opening command output by the PID closed-loop control unit in real time, and simultaneously collects the actual opening feedback signal returned by the corresponding electric control valve, continuously calculating the difference between the two. A preset dead zone is used to accommodate normal valve action lag and signal transmission errors, avoiding the identification of deviations within the normal range as faults; only when the deviation value exceeds the dead zone range, and the abnormal state is maintained continuously for a duration exceeding the second confirmation duration threshold, is subsequent in-depth judgment triggered. Setting the confirmation duration threshold can filter instantaneous deviations during valve action, eliminate interference from transitional states during normal regulation, and ensure the stability of the diagnostic results.

[0091] Specifically, after triggering the depth judgment, the system introduces the measured value of the branch flow as an independent verification basis to distinguish between valve body faults and feedback signal faults. Flow parameters are the direct result of valve adjustment actions and can truly reflect the actual operating state of the water circuit, unaffected by opening feedback signals. If, after the opening command changes, the measured value of the corresponding branch flow does not show the expected change in the same direction, it indicates that the valve core has not followed the command to execute the action, and there is a mechanical structure jamming. This can be determined as a jamming fault in the electric regulating valve body. This type of fault is usually caused by scale deposition in the pipeline, foreign objects blocking the valve core, or wear of the actuator transmission components.

[0092] Furthermore, if the measured branch flow rate changes in a consistent manner after the opening command changes, it indicates that the valve's actual regulating function is normal. If only the opening feedback signal does not match the actual state, it can be determined that the valve opening feedback sensor is faulty. This type of fault is a signal-level anomaly and will not directly affect the cooling capacity of the water circuit; it will only interfere with the accuracy judgment of closed-loop regulation. By clearly distinguishing between these two types of faults, maintenance personnel can adopt different handling solutions. For valve jamming faults, a shutdown for repair should be arranged as soon as possible. For feedback sensor faults, components can be replaced during production breaks without emergency shutdown, thereby reducing the impact of actuator failure on production continuity.

[0093] In some embodiments, when a jamming fault is determined in the electric regulating valve, the fault handling strategy includes: Switch the control mode of the branch corresponding to the stuck valve from PID automatic adjustment to manual locking mode, lock the valve at the current opening degree or the preset safe opening degree; at the same time, block the software signal path of the branch that triggers interlock shutdown due to abnormal flow or temperature difference, retain only the independent hardware protection loop based on the return water temperature exceeding the limit, and generate a valve maintenance work order prompt.

[0094] It should be noted that the "sticking" fault describes an incomplete failure state characterized by sluggish operation and resistance. The valve core or actuator can still move slightly, but the response is delayed, the opening deviation is large, and it cannot accurately reach the command position. This is mostly caused by scale buildup, aging seals, and wear of transmission components leading to increased resistance, and belongs to a mild to moderate mechanical fault.

[0095] In the above solution, this application adopts a method of locking the opening degree and interlocking with the shielding software to deal with valve jamming failure. While retaining the hardware over-temperature protection, it maintains the cooling operation of the branch circuit and reduces unnecessary downtime of the whole machine.

[0096] Specifically, when the system determines that the electric regulating valve body has a jamming fault, the corresponding handling strategy is executed in three levels in sequence: operation maintenance, risk avoidance, and safety backup, maximizing production continuity while ensuring the bottom line of equipment safety. First, the control mode of the branch corresponding to the jammed valve is switched from PID automatic adjustment to manual locking mode, stopping the continuous output of dynamic adjustment commands to the faulty valve. After the valve jams, the valve core cannot respond normally to changes in opening. If PID automatic adjustment continues, the controller will repeatedly output incremental commands due to the continuous deviation between the target value and the measured value. This can easily cause overload damage to the electric actuator and may also aggravate the mechanical wear of the jammed part of the valve core, leading to further deterioration of the fault. The opening locking can prioritize the current opening at the time of the fault. If the current opening deviates too much from the reasonable range, it switches to the preset safe opening to ensure that the branch maintains a stable basic cooling water flow, meeting the minimum heat dissipation requirements of the corresponding cooling point, and preventing cooling interruption due to valve actuator failure.

[0097] Furthermore, the system synchronously blocks the software signal path that would trigger an interlock shutdown for this branch due to abnormal flow or temperature differences. After a valve jams, the branch flow and the temperature difference between the inlet and outlet water will gradually deviate from the normal set range. If the original software interlock logic is retained, a complete unit shutdown protection will be triggered due to actuator failure. However, at this time, the cooling water circuit is still conducting, and the basic cooling function of the branch is not completely lost. Directly triggering a complete unit shutdown would be an over-protection measure. Blocking the corresponding software interlock signal path avoids unnecessary furnace shutdowns caused by actuator failures, maintaining the normal operation of the electric furnace.

[0098] Specifically, while disabling software interlocks, the system retains only an independent hardware protection loop based on excessive return water temperature. This protection loop is directly constructed from independent temperature sensing elements and relays, without relying on PLC software calculations or conventional sensor acquisition links. When the branch return water temperature exceeds the set limit safety threshold, it can directly output a shutdown protection signal, triggering the shutdown of the electric furnace's main operating system. This independent hardware protection loop serves as a final safety fallback mechanism, providing reliable protection when branch cooling capacity is severely insufficient or furnace components are at risk of overheating damage. It avoids safety control failures due to the disabling of interlock signals, balancing the continuity of production operation with the safety of the equipment itself.

[0099] Furthermore, the system synchronously generates valve maintenance work orders, recording the time of the fault, the fault branch number, the fault type, and the current operating parameters, and pushes these to the operation and maintenance management terminal. Maintenance personnel can select appropriate downtime intervals according to the production schedule to perform valve maintenance, cleaning, and replacement without requiring emergency boiler shutdown. This tiered fault-tolerant approach reduces the impact of actuator failures on production rhythm and improves the overall operational fault tolerance and maintenance flexibility of the water-cooling system.

[0100] In some embodiments, the fault handling strategy generated in step S2 further includes: When a single sensor fault is diagnosed, only the instrument fault alarm is triggered, the water circuit abnormal interlock shutdown signal triggered by the fault sensor data of that branch is blocked, and the branch switches to the derating control mode of the remaining effective parameters to maintain the normal operation of the system.

[0101] In the above scheme, this application adopts a derating operation mode for single sensor failure, which only triggers the fault indication and does not trigger the water circuit interlock shutdown, thereby reducing the probability of production interruption while ensuring basic cooling safety.

[0102] Specifically, single sensor drift and disconnection are frequent instrument-related faults during the operation of water-cooling systems. These faults only cause distortion in the measurement data of the corresponding physical quantity and do not directly cause the cooling water circuit to fail. If conventional protection logic is used to directly trigger interlock shutdown based on abnormal data, the instrument fault will be treated as a water circuit fault, causing unnecessary production stoppages. This solution sets up a dedicated fault-tolerant handling logic for single sensor failures. After identifying a single sensor fault, an independent instrument fault alarm is triggered first. The alarm information clearly indicates the faulty branch and the type of faulty component, clearly distinguishing it from water circuit abnormality alarms, which facilitates maintenance personnel to quickly identify the nature of the fault and arrange targeted handling.

[0103] Furthermore, the system synchronously blocks the water circuit abnormality interlock shutdown signal triggered by fault sensor data in this branch, preventing distorted measurement data from triggering incorrect protection actions. The blocking scope is limited to the interlock logic associated with the corresponding faulty sensor and does not deactivate all protection mechanisms for the entire branch. The protection thresholds corresponding to the other normally functioning sensors remain effective and can continue to provide protection when abnormalities occur under actual operating conditions.

[0104] Specifically, while shielding the interlock signal, the cooling branch automatically switches to derating control mode. It no longer uses the physical quantity corresponding to the faulty sensor as the closed-loop control target, but instead executes a conservative control strategy based on the parameters of other normally functioning sensors. For example, when a single branch return water temperature sensor fails, the branch control logic switches from the original temperature difference closed-loop regulation to constant flow control mode, maintaining the branch water supply with a fixed target of a safe flow rate under the current operating conditions, ensuring basic heat dissipation capacity through a stable cooling water flow. When a branch flow sensor fails, it switches to a combined control mode based on inlet water pressure and return water temperature, indirectly ensuring water flow capacity through pressure parameters. The derating control mode abandons the original high-precision dynamic adjustment capability, but can maintain the basic operation of the branch cooling function even when a single instrument fails, ensuring that the corresponding furnace components do not experience cooling interruptions.

[0105] Furthermore, the entire handling strategy can be executed automatically without manual intervention. After a fault is triggered, the system automatically completes mode switching and signal shielding, while recording the time, branch, and fault type, and generating maintenance prompts. Maintenance personnel do not need to shut down the system immediately; they can select appropriate downtime intervals in conjunction with the production schedule to complete the calibration or replacement of faulty sensors. Instrument maintenance can be completed without affecting the normal production rhythm, effectively reducing the impact of single instrument failures on production continuity and improving the overall operational reliability of the system.

[0106] In some embodiments, in step S3, when the electric furnace load increases and the return water temperature of a single branch rises, the PID closed-loop control unit increases the opening of the corresponding branch electric control valve to increase the cooling water flow; when the return water temperature is lower than the set value, the valve opening is reduced to achieve balanced cooling of the furnace body and energy-saving operation.

[0107] In the above scheme, this application dynamically adjusts the valve opening according to the return water temperature to match the cooling requirements of the electric furnace under different loads, so that the cooling water volume of each branch can be dynamically adjusted according to the operating conditions.

[0108] Specifically, the load on the electric furnace is dynamically changing during actual production. During the smelting and heating phase, the heating power is high, and components such as the furnace body induction coil and magnetic yoke generate significant heat. During the heat preservation and discharge phase, the power decreases, and the heat generation decreases accordingly. Traditional water cooling systems often use a constant flow water supply mode, typically configuring the cooling water flow rate according to the maximum load condition. This leads to wasted energy during low-load phases, and supplying water to different cooling points with the same flow rate cannot match the differentiated heating characteristics of each component, easily resulting in localized insufficient or excessive cooling. This solution implements independent PID closed-loop regulation for each cooling branch, using the branch return water temperature or the inlet / outlet water temperature difference as the control target. It compares the deviation between the measured value and the set value in real time, and outputs corresponding valve opening commands through proportional, integral, and derivative calculations to dynamically adjust the cooling water flow rate of each branch.

[0109] Furthermore, when the furnace load increases and the corresponding branch return water temperature rises, the PID unit automatically increases the opening of the electric regulating valve to increase the branch cooling water flow, enhance heat exchange capacity, and pull the return water temperature back to the set range, preventing overheating at the cooling points. When the furnace load decreases and the return water temperature falls below the set value, the valve opening automatically decreases, reducing the branch cooling water flow and minimizing the output power consumption of the circulating water pump while meeting cooling requirements. The independent adjustment mode for each branch can adapt to the heat generation differences at different cooling points, ensuring balanced cooling effects across all parts of the furnace body, avoiding excessive local temperature differences that could affect equipment lifespan, and simultaneously enabling on-demand water supply, reducing the overall energy consumption of the water cooling system.

[0110] In some embodiments, the control method further includes a data storage and uploading step: all operating parameters, fault records, and protection action logs are synchronously stored in a historical database and can be uploaded to the factory's DCS, MES, or SCADA system via remote communication. This application, through the full storage and network uploading of operating data and event logs, can provide data support for fault tracing, system optimization, and plant-wide management, achieving traceability and centralized management of water-cooling system operating data.

[0111] Specifically, the local historical database stores data categorized by data type. Regular operating parameters, including temperature, pressure, flow rate, and valve opening data for each node, are stored as averages at fixed time intervals for long-term trend analysis. Raw data for the periods before and after a fault is stored using a higher sampling frequency, comprehensively recording the entire process of fault occurrence, development, and handling. This facilitates post-fault cause tracing and verification of the accuracy of diagnostic logic. Fault records and protection action logs are archived separately, containing complete information such as fault occurrence time, fault branch, fault type, handling measures, and protection action trigger times, serving as the primary basis for equipment operation and maintenance and fault analysis.

[0112] Furthermore, the system supports standard industrial communication protocols via a remote communication unit, enabling the uploading of aggregated operational data, alarm information, and equipment status to the factory-level DCS, MES, or SCADA control systems. This allows for the integration of a single water-cooling system with the entire plant's production control system. After uploading, management personnel can view the operational status of all electric furnace water-cooling systems in the central monitoring room and receive unified fault alarms and maintenance prompts, eliminating the need for on-site inspections of each device. Once the data is integrated into the production system, it can also be linked with the electric furnace's production plan and power scheduling data. By combining this with the production rhythm, changes in cooling load can be predicted in advance, providing data support for the optimization of the entire plant's water system scheduling and improving the overall efficiency of the plant's operation and maintenance management.

[0113] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A closed-loop water distribution system for monitoring electric furnace body, characterized in that, This includes an inlet water distribution and regulation system, a furnace cooling load unit, a return water collection and monitoring system, and a PLC control layer; The water inlet distribution and regulation system includes a main water inlet pipe monitoring unit and a water inlet distributor unit. The main water inlet pipe monitoring unit is connected to the water inlet distributor unit. The main water inlet pipe monitoring unit integrates a temperature sensor, a pressure sensor, and a flow sensor. The water inlet distributor unit is equipped with multiple independent water inlet branch pipes. Each water inlet branch pipe is independently equipped with a temperature sensor, a pressure sensor, a flow sensor, and an electric regulating valve. The furnace cooling load unit includes multiple independent cooling branches, which correspond to the upper and lower short-circuit rings of the electric furnace, the cooling points of the magnetic yoke, and the cooling branches of the furnace induction coil. The water inlet of each cooling branch is connected to the water inlet branch of the water inlet water dispenser unit, and there is no series connection between the cooling branches. The return water collection and monitoring system includes a return water main pipe monitoring unit and a return water distributor unit. The return water main pipe monitoring unit is connected to the return water distributor unit. The return water main pipe monitoring unit integrates a temperature sensor, a pressure sensor, and a flow sensor. The return water distributor unit is equipped with multiple independent return water branch pipes, and each return water branch pipe is independently equipped with a temperature sensor, a pressure sensor, and a flow sensor. The outlet of each cooling branch pipe is connected to the return water branch pipe of the return water distributor unit one by one. The PLC control layer includes a data acquisition and preprocessing unit, a PID closed-loop regulation unit, a sensor and actuator self-diagnosis unit, and a hierarchical interlocking protection unit; the signal output terminals of all temperature sensors, pressure sensors, and flow sensors are connected to the data acquisition and preprocessing unit. The data acquisition and preprocessing unit is connected to the PID closed-loop control unit and the sensor and actuator self-diagnosis unit respectively; the output terminals of the PID closed-loop control unit and the sensor and actuator self-diagnosis unit are both connected to the graded interlocking protection unit; the control output terminal of the PID closed-loop control unit is connected to the electric regulating valve of each water inlet branch pipe to form a closed-loop control circuit; the interlocking output terminal of the graded interlocking protection unit is used to connect to the main operating system of the electric furnace.

2. A control method, comprising the water distribution system as described in claim 1, characterized in that, Includes the following steps: S1: Real-time acquisition of temperature, pressure, and flow operating parameters of the main inlet pipe, each inlet branch pipe, each return branch pipe, and the main return pipe; synchronous acquisition of actual opening feedback signals of the electric regulating valves of each branch pipe. S2: Perform fault diagnosis on the collected sensor data and actuator status, the fault diagnosis including: The first diagnostic mechanism performs correlation trend analysis on at least two different physical quantity sensors on the same branch. When the rate of change of the first physical quantity exceeds a preset reasonable threshold and the second physical quantity does not show a corresponding change that conforms to the physical law, it is determined to be an instrument malfunction. The second diagnostic mechanism sums up the flow rate and temperature difference parameters of all operating branches and performs dynamic material balance or heat balance verification with the measured values ​​of the corresponding parameters of the inlet or return water main. When the deviation between the summed value of the branch and the measured value of the main exceeds the preset tolerance, the specific faulty branch and fault type are located by combining the branch correlation trend analysis results. Based on the judgment results of the first and second diagnostic mechanisms, the instrument failure is distinguished from the actual working condition of the water circuit, and corresponding fault handling strategies are generated. S3: Using the temperature difference between the inlet and outlet water of a single branch, the flow rate of the branch, or the pressure of the branch as the control target, the PID calculation outputs the opening adjustment command to the electric regulating valve of the corresponding branch to adjust the water supply of each cooling branch. S4: Compare the collected waterway operating parameters with the preset protection threshold to determine the protection level corresponding to the current operating condition; S5: Based on the determined protection level, corresponding protection actions will be executed, including early warning prompts, audible and visual alarms, and shutdown of the main operating system of the electric furnace.

3. The integrated monitoring and closed-loop control method for water-cooled electric furnace body according to claim 2, characterized in that, The correlation trend analysis of the first diagnostic mechanism in step S2 includes: Time series correlation analysis is performed on the temperature sensor and flow sensor on the same branch to calculate the ratio of temperature change rate ΔT / Δt to flow change rate ΔQ / Δt in real time. When the ratio exceeds the normal coupling range preset according to the electric furnace operating conditions and the duration exceeds the first confirmation time threshold, it is determined that the temperature sensor of the branch has a drift fault, or the flow sensor has a drift or jamming fault.

4. The closed-loop control method for integrated monitoring of water-cooled electric furnace body according to claim 2, characterized in that, The dynamic material balance verification and thermal balance verification of the second diagnostic mechanism in step S2 are specifically as follows: Material balance verification: Sum the instantaneous inflow values ​​of all operating branches to obtain the total branch flow ΣQbranch, and compare it with the measured value of the total inflow flow Qtotal. When |ΣQbranch-Qtotal| / Qtotal > preset material tolerance rate, it is determined that there is an abnormality in the branch flow measurement or the total flow measurement. Heat balance verification: Calculate the sum of the products of the flow rate of each branch and the corresponding inlet and outlet water temperature difference Σ(Q_branch × ΔT_branch), and compare it with the calculated value of the inlet main pipe flow rate multiplied by the total system temperature difference Q_total_inlet × (T_total_return - T_total_inlet). When the absolute value of the deviation between the two is greater than the ratio of the total heat exchange of the system to the preset heat balance deviation rate, it is determined that there is an abnormality in the branch temperature measurement, branch flow measurement, or main pipe temperature measurement.

5. The integrated monitoring and closed-loop control method for water-cooled electric furnace body according to claim 3 or 4, characterized in that, In step S2, the specific faulty branch and fault type are located by combining the branch correlation trend analysis results, using cross-validation logic: When the second diagnostic mechanism determines that there is a system-level deviation, and the first diagnostic mechanism of a certain branch simultaneously determines that there is an instrument fault in that branch, the branch is marked as a faulty branch, and the faulty sensor type is determined according to the attributes of the abnormal physical quantities in the correlation trend analysis. When the second diagnostic mechanism determines that there is a system-level deviation, but the first diagnostic mechanism of all branches does not give a fault determination of the instrument, the fault source is located as the inlet main pipe sensor or the return main pipe sensor, and a main pipe instrument maintenance prompt is issued.

6. The integrated monitoring and closed-loop control method for water-cooled electric furnace body according to claim 2, characterized in that, The fault diagnosis described in step S2 also includes an actuator diagnosis sub-step: Real-time acquisition of opening feedback signals of each electric regulating valve, continuous comparison of the opening feedback signals with the opening command output by the PID closed-loop regulating unit, when the deviation value exceeds the preset dead zone and continues to exceed the second confirmation time threshold, further determination of whether the measured flow value of the corresponding branch changes with the opening command. If the measured flow rate does not change as expected with the opening command, the electric regulating valve is determined to have a jamming fault. If the measured flow rate changes normally with the opening command, it is determined that the valve opening feedback sensor is faulty.

7. The integrated monitoring and closed-loop control method for water-cooled electric furnace body according to claim 6, characterized in that, When a jamming fault is determined in the electric regulating valve, the fault handling strategy includes: Switch the control mode of the branch corresponding to the stuck valve from PID automatic adjustment to manual locking mode, lock the valve at the current opening degree or the preset safe opening degree; at the same time, block the software signal path of the branch that triggers interlock shutdown due to abnormal flow or temperature difference, retain only the independent hardware protection loop based on the return water temperature exceeding the limit, and generate a valve maintenance work order prompt.

8. The integrated monitoring and closed-loop control method for water-cooled electric furnace body according to claim 2, characterized in that, The fault handling strategy generated in step S2 also includes: When a single sensor fault is diagnosed, only the instrument fault alarm is triggered, the water circuit abnormal interlock shutdown signal triggered by the fault sensor data of that branch is blocked, and the branch switches to the derating control mode of the remaining effective parameters to maintain the normal operation of the system.

9. The closed-loop control method for integrated monitoring of water-cooled electric furnace body according to claim 2, characterized in that, In step S3, when the electric furnace load increases, causing the return water temperature of a single branch to rise, the PID closed-loop control unit increases the opening of the corresponding branch electric regulating valve to increase the cooling water flow; when the return water temperature is lower than the set value, the valve opening is reduced to achieve balanced cooling of the furnace body and energy-saving operation.

10. The integrated monitoring and closed-loop control method for water-cooled electric furnace body according to claim 2, characterized in that, It also includes data storage and uploading steps: all operating parameters, fault records and protection action logs are synchronously stored in the historical database and can be uploaded to the factory DCS, MES or SCADA system via remote communication.

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