Pipeline anti-freezing control method, system, storage medium and computer device

Abstract

The application relates to the technical field of pipeline anti-freezing, and discloses a pipeline anti-freezing control method, a pipeline anti-freezing control system, a storage medium and computer equipment, the method is applied to a pipeline anti-freezing control system comprising a first control unit, a second control unit and a heating execution unit, and the method comprises the following steps: under a steady state condition, the first control unit drives to control the heating execution unit to execute steady state temperature closed loop control; when a transient state condition trigger condition is met, a net heat loss accumulation is calculated according to real-time heat dissipation parameters, and when a switching threshold value is reached, the system is switched to the second control unit to drive to control the heating execution unit; the second control unit adjusts the output power of the heating execution unit according to the real-time heat dissipation parameters, compares the net heat loss accumulation with a maximum allowed heat loss threshold value, and outputs a graded early warning signal; when the net heat loss accumulation is lower than the switching threshold value and lasts for a preset time length, the system is switched back to the first control unit to execute the steady state temperature closed loop control. The above method improves response timeliness and control reliability, and reduces operation energy consumption.

Description

Technical Field

[0001] This invention relates to the field of pipeline antifreeze technology, and in particular to a pipeline antifreeze control method, system, storage medium, and computer equipment. Background Technology

[0002] Long-distance and process pipelines, especially those primarily buried with exposed sections connected by bridges or added later, experience significantly increased heat dissipation rates under low temperatures and strong winds, making them prone to freezing and blockage. To ensure safe pipeline operation, current technologies typically employ heating devices for freeze protection and regulate heating output through temperature acquisition and control. However, these pipelines often have both buried and exposed sections, with differences in thermal inertia, heat dissipation conditions, and response speeds between the different sections. Furthermore, the dynamic nature of weather conditions creates multiple challenges for freeze protection control, balancing response speed, control reliability, and operational energy consumption.

[0003] Existing pipeline antifreeze solutions generally use single-point temperature measurement with temperature sensors. When the detected pipeline temperature drops to a set threshold, the output power of the heating device is directly controlled to implement heating. This type of solution has the following prominent problems: On the one hand, the adjustment method of heating output is relatively simple and cannot adapt to the dynamic changes in meteorological conditions and pipeline heat dissipation status, making it difficult to achieve a good balance between energy consumption control and antifreeze protection; on the other hand, the control effect is quite sensitive to operating conditions, and control deviations are prone to occur when operating conditions change, affecting the stability and reliability of pipeline temperature control.

[0004] Therefore, a pipeline antifreeze control method that improves the effectiveness of pipeline antifreeze control to adapt to dynamic operating conditions is urgently needed. Summary of the Invention

[0005] In view of this, this application provides a pipeline antifreeze control method, system, storage medium and computer equipment, the main purpose of which is to solve the technical problems that existing pipeline antifreeze solutions are difficult to balance energy consumption control and antifreeze protection, and that control reliability is easily affected by changes in operating conditions.

[0006] According to a first aspect of the present invention, a pipeline antifreeze control method is provided, applied to a pipeline antifreeze control system, the pipeline antifreeze control system including a first control unit, a second control unit, and a heating execution unit, the method comprising: Under steady-state conditions, the first control unit drives and controls the heating execution unit to perform steady-state temperature closed-loop control on the target pipeline. When the transient operating condition triggering condition is met, the second control unit calculates the net heat loss accumulation based on the real-time heat dissipation parameters of the target pipeline. When the cumulative net heat loss reaches the switching threshold, the drive output of the heating execution unit is switched from the first control unit to the second control unit; During the period when the second control unit drives and controls the heating execution unit, the second control unit adjusts the output power of the heating execution unit according to the real-time heat dissipation parameters, compares the net heat loss accumulation with the preset maximum allowable heat loss threshold, and outputs a graded early warning signal. When the cumulative net heat loss is lower than the switching threshold and continues for a preset duration, the drive output of the heating execution unit is switched from the second control unit to the first control unit, and the first control unit drives and controls the heating execution unit to perform steady-state temperature closed-loop control.

[0007] According to a second aspect of the present invention, a pipeline antifreeze control system is provided, comprising: a first control unit, a second control unit, and a heating execution unit; The first control unit is used to drive and control the heating execution unit to perform steady-state temperature closed-loop control on the target pipeline under steady-state operating conditions; The second control unit is used to calculate the net heat loss accumulation based on the real-time heat dissipation parameters of the target pipeline when the transient operating condition triggering condition is met; when the net heat loss accumulation reaches the switching threshold, it drives and controls the heating execution unit. The second control unit is also configured to adjust the output power of the heating execution unit according to the real-time heat dissipation parameters during the driving control of the heating execution unit, compare the net heat loss accumulation with the preset maximum allowable heat loss threshold, and output a graded warning signal; The first control unit is further configured to drive and control the heating execution unit to perform steady-state temperature closed-loop control when the net heat loss accumulation is lower than the switching threshold and continues for a preset duration.

[0008] According to a third aspect of the present invention, a storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the above-described pipeline antifreeze control method.

[0009] According to a fourth aspect of the present invention, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the above-described pipeline antifreeze control method.

[0010] This invention provides a pipeline antifreeze control method, system, storage medium, and computer equipment. First, under steady-state conditions, a first control unit drives and controls a heating execution unit to perform steady-state temperature closed-loop control on the target pipeline. This ensures the pipeline maintains a stable antifreeze state through temperature closed-loop control when weather conditions are relatively stable, avoiding the problem of increased control deviation due to changes in operating conditions when relying solely on power control, thus improving the stability and reliability of pipeline temperature control. Second, when transient operating conditions are triggered, the net heat loss accumulation is calculated based on the real-time heat dissipation parameters of the target pipeline. When the net heat loss accumulation reaches a switching threshold, the system switches to control the heating execution unit driven by a second control unit. This allows the antifreeze control to promptly transition from steady-state temperature closed-loop control to transient control when operating conditions dynamically change, no longer relying solely on temperature thresholds to trigger protection actions, which is beneficial for improving protection. The method prioritizes the anticipation and timeliness of actions. Then, when the second control unit drives the heating execution unit, it adjusts the output power of the heating execution unit based on real-time heat dissipation parameters and compares the net heat loss accumulation with the maximum allowable heat loss threshold to output graded early warning signals. This allows the heating output to adjust according to the actual heat dissipation state of the pipeline, avoiding direct output of heating power in a single mode when weather conditions change abruptly. This helps to achieve a balance between energy consumption control and antifreeze protection, and allows for early output of graded early warnings when the net heat loss accumulation reaches the corresponding threshold, improving the timeliness of antifreeze protection. Finally, when the net heat loss accumulation is below the switching threshold and remains below it for a preset duration, the system switches to steady-state temperature closed-loop control driven by the first control unit. This allows the system to return to steady-state temperature closed-loop control after the transient condition eases, ensuring temperature control stability and reducing operating energy consumption. The above method, through the coordination of steady-state temperature closed-loop control and transient control, as well as the calculation of net heat loss accumulation based on real-time heat dissipation parameters, power adjustment, and graded early warnings, improves the responsiveness and control reliability of the pipeline antifreeze scheme, and reduces operating energy consumption.

[0011] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0012] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 A schematic flowchart of a pipeline antifreeze control method provided by an embodiment of the present invention is shown; Figure 2A schematic flowchart of another pipeline antifreeze control method provided by an embodiment of the present invention is shown; Figure 3 This diagram illustrates the structure of a pipeline antifreeze control system provided in an embodiment of the present invention. Figure 4 A schematic diagram of the device structure of a computer device provided in an embodiment of the present invention is shown. Detailed Implementation

[0013] Exemplary embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0014] This application provides a pipeline antifreeze control method, which is applied to a pipeline antifreeze control system. The pipeline antifreeze control system includes a first control unit, a second control unit, and a heating execution unit.

[0015] The heating execution unit provides heat to the target pipeline for freeze protection. Specifically, it can be an electric heat tracing device, an electric heating device, or other execution equipment capable of heating the pipeline. The first control unit and the second control unit are respectively connected to the heating execution unit and are used to drive and control the heating execution unit. The first and second control units can be independent control devices, such as independent microcontrollers, controllers, or control circuits, or they can be independent control logic units within the same control platform. The first and second control units can respectively collect the operating parameters and environmental parameters of the target pipeline and output corresponding drive signals to the heating execution unit accordingly. It should be noted that the specific form of the first control unit, the second control unit, and the heating execution unit does not constitute a limitation on this application, as long as the corresponding control and heating functions can be achieved.

[0016] like Figure 1 As shown, the method includes: 101. Under steady-state conditions, the first control unit drives and controls the heating execution unit to perform steady-state temperature closed-loop control on the target pipeline.

[0017] Among them, steady-state operating condition refers to a relatively stable state in which the meteorological conditions of the target pipeline environment and / or the operating state of the target pipeline are, such as when parameters such as ambient temperature, ambient wind speed, pipe medium temperature, and pipe medium flow rate do not change drastically or abruptly. In actual operation, pipeline antifreeze control usually faces the problem of dynamic changes in meteorological conditions. When parameters such as ambient temperature and wind speed are relatively stable, the heat dissipation state of the pipeline is also relatively stable. At this time, a control method based on temperature feedback is suitable. Steady-state temperature closed-loop control refers to using the pipeline temperature of the target pipeline as the controlled variable, comparing it with the preset target temperature, and adjusting the drive signal output to the heating execution unit according to the temperature deviation obtained from the comparison, so that the pipeline temperature tends to or maintains near the target temperature. Drive control refers to the first control unit outputting a drive signal to the heating execution unit to control the heating output of the heating execution unit. The target temperature can be preset according to the antifreeze requirements of the target pipeline, for example, set to a temperature value higher than the freezing point of the medium in the pipeline, so as to leave a safety margin between the pipeline temperature and the risk of freezing blockage.

[0018] Specifically, under steady-state conditions, the first control unit collects the pipe temperature of the target pipe and compares it with the preset target temperature to obtain the temperature deviation. The first control unit adjusts the drive signal output to the heating execution unit based on the temperature deviation, for example, by adjusting the duty cycle or on / off state of the drive signal, thereby adjusting the heating output of the heating execution unit to bring the pipe temperature of the target pipe closer to the target temperature. If the pipe temperature is lower than the target temperature, the heating output is increased; if the pipe temperature is higher than the target temperature, the heating output is decreased or heating is stopped. Since the control process uses the pipe temperature as feedback and continuously adjusts it, a steady-state temperature closed-loop control of the target pipe is formed. During the steady-state temperature closed-loop control process, the first control unit, as the main control unit under steady-state conditions, drives and controls the heating execution unit, enabling the target pipe to maintain a stable anti-freezing state when meteorological conditions are relatively stable. It should be noted that the specific implementation of the temperature closed-loop control can employ proportional control, proportional-integral control, proportional-integral-derivative control, or threshold switching control, etc., and this application does not limit this method.

[0019] In this embodiment, by employing steady-state temperature closed-loop control under steady-state operating conditions, the target pipeline can maintain a stable antifreeze state based on temperature feedback when meteorological conditions are relatively stable. This avoids the problem of increased control deviation due to changes in operating conditions when relying solely on power control, thus improving the stability and reliability of pipeline temperature control. Simultaneously, since temperature closed-loop control is the primary method under steady-state operating conditions, the control logic is simple and reliable, which helps reduce control complexity and energy consumption during steady-state operation. Furthermore, since the first control unit independently executes temperature closed-loop control under steady-state operating conditions, there is no need to initiate transient control logic, which helps reduce the computational burden on the control system and reserves control resources for subsequent control switching under transient operating conditions.

[0020] 102. When the transient operating condition triggering condition is met, the second control unit calculates the net heat loss accumulation based on the real-time heat dissipation parameters of the target pipeline; when the net heat loss accumulation reaches the switching threshold, the drive output of the heating execution unit is switched from the first control unit to the second control unit.

[0021] Among them, the transient operating condition triggering condition refers to the condition used to determine that the target pipeline enters the transient operating condition from the steady-state operating condition. The transient operating condition refers to the operating condition in which the meteorological conditions of the environment where the target pipeline is located and / or the operating state of the target pipeline change drastically, causing the pipeline's heat dissipation state to deviate from the steady state, such as a sudden drop in ambient temperature or a sudden increase in ambient wind speed. The real-time heat dissipation parameters refer to the parameters that can reflect the current heat dissipation state of the target pipeline, including the ambient temperature and ambient wind speed of the environment where the target pipeline is located, as well as the pipeline temperature, the temperature of the medium inside the pipe, and the flow rate of the medium inside the pipe. The net heat loss accumulation refers to the accumulation obtained by integrating the net heat loss power of the target pipeline under the transient operating condition over time, which is used to characterize the heat loss accumulated by the target pipeline over a period of time. The switching threshold is a pre-set net heat loss accumulation threshold used to trigger the switching of the control mode to the second control unit driving and controlling the heating execution unit. Specifically, the drive output of the heating execution unit is transferred from the first control unit to the second control unit, so that the second control unit takes over the drive control of the heating execution unit from the first control unit.

[0022] Specifically, when the meteorological conditions or operating status of the target pipeline change drastically, causing the system to determine that the transient operating condition triggering condition is met, the second control unit calculates the net heat loss accumulation based on the real-time heat dissipation parameters of the target pipeline. The second control unit can obtain the ambient temperature and wind speed of the target pipeline environment, as well as the real-time heat dissipation parameters such as the pipeline temperature, the temperature of the medium inside the pipe, and the flow rate of the medium inside the pipe, and determine the real-time net heat loss power of the target pipeline accordingly. Then, the real-time net heat loss power is integrated over time to obtain the net heat loss accumulation. After calculating the net heat loss accumulation, the net heat loss accumulation is compared with a preset switching threshold. When the net heat loss accumulation reaches the switching threshold, the drive output of the heating execution unit is switched from the first control unit to the second control unit, and the second control unit drives and controls the heating execution unit. In summary, the system no longer triggers the protection action simply based on whether the pipeline temperature is lower than a certain temperature threshold. Instead, after determining that a transient operating condition has been entered, the control mode is switched by the net heat loss accumulation reaching the switching threshold, so that the heating execution unit is promptly taken over by the second control unit.

[0023] In this embodiment, the above-mentioned method enables the antifreeze control to switch from steady-state temperature closed-loop control to transient control in a timely manner when meteorological conditions or operating status change drastically, no longer relying solely on temperature thresholds to trigger protection actions. This improves the advance nature and timeliness of protection actions. At the same time, since the net heat loss accumulation is used as the switching basis, the actual heat loss of the target pipeline can be reflected from the perspective of heat accumulation, avoiding delays in protection actions caused by temperature sensor response lag. This allows for the activation of corresponding control measures before the pipeline temperature drops to a dangerous value, reducing the risk of pipeline freezing and blockage.

[0024] 103. When the second control unit drives and controls the heating execution unit, the second control unit adjusts the output power of the heating execution unit according to the real-time heat dissipation parameters, compares the net heat loss accumulation with the preset maximum allowable heat loss threshold, and outputs a graded warning signal.

[0025] Specifically, the second control unit drives the heating execution unit by outputting a drive signal to control the heating output of the heating execution unit. At this point, the system has switched from steady-state temperature closed-loop control to transient control. Real-time heat dissipation parameters reflect the current heat dissipation status of the target pipe, including the ambient temperature and wind speed of the target pipe, as well as the pipe temperature, internal medium temperature, and internal medium flow rate. Output power refers to the power corresponding to the heat provided by the heating execution unit to the target pipe per unit time. The maximum permissible heat loss threshold is a pre-set threshold for determining whether the cumulative heat loss of the target pipe has reached the warning level. The maximum permissible heat loss threshold is greater than the switching threshold. The graded warning signal refers to the warning signal output according to different warning levels based on the comparison between the cumulative net heat loss and the maximum permissible heat loss threshold.

[0026] Specifically, the second control unit can acquire the ambient temperature and wind speed of the target pipeline, as well as real-time heat dissipation parameters such as the pipeline temperature, internal medium temperature, and internal medium flow rate. Based on this, it determines the real-time net heat loss power of the target pipeline and adjusts the output power of the heating execution unit according to the real-time net heat loss power, so that the heating output can follow the actual heat dissipation state of the target pipeline, rather than outputting at a fixed power or in a single mode. At the same time, the second control unit compares the calculated net heat loss accumulation with the preset maximum allowable heat loss threshold and outputs graded warning signals based on the comparison results. For example, when the net heat loss accumulation approaches the maximum allowable heat loss threshold, a lower-level warning signal can be output; when the net heat loss accumulation reaches or exceeds the maximum allowable heat loss threshold, a higher-level warning signal can be output. Through graded warnings, operators can judge the degree of heat loss of the pipeline according to the warning level and take corresponding measures.

[0027] In this embodiment, the heating output can be adjusted according to the actual heat dissipation state of the target pipeline through the above-mentioned method, rather than directly outputting heating power in a single way when the weather conditions change suddenly. This helps to achieve a better balance between energy consumption control and antifreeze protection. At the same time, since the net heat loss accumulation is compared with the maximum allowable heat loss threshold and a graded early warning signal is output, the degree of heat loss of the pipeline can be quantitatively assessed from the perspective of heat accumulation. Early warning is output before the pipeline temperature drops to a dangerous value, overcoming the shortcomings of the temperature sensor response lag and further improving the timeliness and safety of antifreeze protection.

[0028] 104. When the cumulative net heat loss is lower than the switching threshold and continues for a preset duration, the drive output of the heating execution unit is switched from the second control unit to the first control unit, and the first control unit drives and controls the heating execution unit to perform steady-state temperature closed-loop control.

[0029] The preset duration refers to the pre-set duration used to determine whether the transient condition has been alleviated. It can be set according to factors such as the length of the control cycle, the system response speed, and the thermal inertia of the target pipeline. When the net heat loss accumulation is lower than the switching threshold, it means that the net heat loss of the target pipeline per unit time has been reduced and the transient condition has tended to be alleviated. Then, the control unit is switched to be driven and controlled by the first control unit. Specifically, the drive output of the heating execution unit is transferred from the second control unit back to the first control unit, so that the first control unit takes over the drive control of the heating execution unit from the second control unit.

[0030] Specifically, during the process of the second control unit driving and controlling the heating execution unit, the net heat loss accumulation is continuously calculated and compared with the switching threshold. When the net heat loss accumulation is lower than the switching threshold and this state continues for a preset duration, it is determined that the transient condition has eased, and the system switches from transient control back to steady-state control. Specifically, the drive output of the heating execution unit is returned from the second control unit to the first control unit, which then re-acquires the pipe temperature of the target pipe and adjusts the drive signal output to the heating execution unit according to the temperature deviation between the pipe temperature and the preset target temperature, so that the target pipe re-enters steady-state temperature closed-loop control. Thus, it can be seen that the transient control is not permanent, but automatically exits after the net heat loss accumulation drops and stabilizes for a preset duration, allowing the system to return to steady-state temperature closed-loop control. It should be noted that if the net heat loss accumulation reaches the switching threshold again during the exit process, the system can maintain the second control unit driving and controlling the heating execution unit, thereby avoiding premature exit from transient control before the transient condition has truly eased.

[0031] In this embodiment, the above method enables the system to automatically return to steady-state temperature closed-loop control after the transient condition is relieved, avoiding long-term transient control and balancing control stability and operating energy consumption. At the same time, since exiting transient control requires the net heat loss accumulation to be lower than the switching threshold for a preset duration, it can avoid frequent switching of control mode due to a short-term drop in net heat loss accumulation, which is beneficial to improving the stability and reliability of the control process.

[0032] This invention provides a pipeline antifreeze control method. First, under steady-state operating conditions, a first control unit drives and controls a heating execution unit to perform steady-state temperature closed-loop control on the target pipeline. This allows the pipeline to maintain a stable antifreeze state through temperature closed-loop control when weather conditions are relatively stable, avoiding the problem of increased control deviation due to changes in operating conditions when relying solely on power control, thus improving the stability and reliability of pipeline temperature control. Second, when the transient operating condition triggering condition is met, the net heat loss accumulation is calculated based on the real-time heat dissipation parameters of the target pipeline. When the net heat loss accumulation reaches a switching threshold, the system switches to control the heating execution unit driven by a second control unit. This allows the antifreeze control to promptly switch from steady-state temperature closed-loop control to transient control when operating conditions change dynamically, no longer relying solely on temperature thresholds to trigger protection actions. This improves the predictability and effectiveness of protection actions. The system prioritizes timely response. Subsequently, when the second control unit drives the heating execution unit, it adjusts the output power of the heating execution unit based on real-time heat dissipation parameters and compares the net heat loss accumulation with the maximum allowable heat loss threshold to output graded early warning signals. This allows the heating output to adjust according to the actual heat dissipation state of the pipeline, avoiding direct output of heating power in a single mode when weather conditions change abruptly. This helps achieve a balance between energy consumption control and antifreeze protection, and allows for early output of graded early warnings when the net heat loss accumulation reaches the corresponding threshold, improving the timeliness of antifreeze protection. Finally, when the net heat loss accumulation is below the switching threshold and remains below it for a preset duration, the system switches to steady-state temperature closed-loop control driven by the first control unit. This allows the system to return to steady-state temperature closed-loop control after the transient condition eases, ensuring temperature control stability and reducing operating energy consumption. The above method, through the coordination of steady-state temperature closed-loop control and transient control, as well as the calculation of net heat loss accumulation based on real-time heat dissipation parameters, power adjustment, and graded early warnings, improves the responsiveness and control reliability of the pipeline antifreeze scheme, while reducing operating energy consumption.

[0033] This application provides another method for pipeline antifreeze control, such as... Figure 2 As shown, it specifically includes: 201. Steady-state temperature closed-loop control.

[0034] In one embodiment, under steady-state conditions, the first control unit drives and controls the heating execution unit to perform steady-state temperature closed-loop control on the target pipeline. Specifically, the first control unit collects the pipeline temperature of the target pipeline and adjusts the drive signal output to the heating execution unit according to the temperature deviation between the pipeline temperature and the preset target temperature, so that the target pipeline maintains a stable antifreeze state when the weather conditions are relatively stable. For specific implementation details, please refer to step 101, which will not be elaborated on here.

[0035] 202. Triggering judgment of transient operating conditions.

[0036] In one implementation, when the transient operating condition triggering condition is met, the system switches from steady-state control to transient control. The transient operating condition triggering condition may include at least one of strong wind disturbance triggering and windless extreme cold triggering.

[0037] Specifically, the determination method for triggering strong wind disturbance includes: collecting the wind speed signal of the environment where the target pipeline is located; filtering the wind speed signal for two consecutive heating drive PWM cycles, wherein the heating drive PWM cycles of the output drive signals of the first control unit and the second control unit are the same; when the filtered wind speed signal is greater than or equal to the preset wind level threshold, it is determined that the transient operating condition triggering condition is met.

[0038] Specifically, in long-distance and process pipelines, especially those with exposed pipe sections due to bridge connections or subsequent additions, the surface convective heat transfer coefficient of the exposed pipe sections increases significantly during strong winds, leading to a sharp increase in the heat dissipation rate. Unlike the steady-state condition where the temperature decreases slowly, the increased heat dissipation caused by strong wind disturbances is sudden and dynamic. If protection actions are triggered solely by temperature thresholds, heating is often only initiated when the pipeline temperature is already close to the danger level, resulting in insufficient advance warning of protection actions. Therefore, it is necessary to establish an independent triggering and judgment method for strong wind disturbances, enabling the system to determine the transition to transient conditions in the early stages of strong wind disturbances.

[0039] In this embodiment, the method for determining whether a strong wind disturbance has occurred includes: First, collecting the wind speed signal of the environment where the target pipeline is located. The wind speed signal directly reflects the convective heat dissipation conditions of the environment where the target pipeline is located and is the direct basis for determining whether a strong wind disturbance has occurred. Second, filtering the wind speed signal for two consecutive heating drive PWM cycles. Since natural wind has pulsation and instantaneous fluctuations, if the instantaneous wind speed is directly used as the basis for determination, it is easy to trigger the transient condition due to instantaneous gusts or wind speed fluctuations, resulting in frequent switching of control modes. By filtering the wind speed signal for two consecutive heating drive PWM cycles, the wind speed determination result can be kept stable in the time dimension, filtering out instantaneous fluctuation interference. Only when the wind speed meets the corresponding conditions within two consecutive heating drive PWM cycles will it proceed to the subsequent determination, thereby improving the accuracy and stability of the trigger determination. Finally, when the filtered wind speed signal is greater than or equal to a preset wind level threshold, it is determined that the transient condition triggering condition is met. The preset wind level threshold can be preset according to the laying conditions, insulation conditions, and antifreeze requirements of the target pipeline.

[0040] In one embodiment, the heating drive PWM period is the PWM period of the drive signal output by the first control unit, and the heating drive PWM period of the second control unit is the same as that of the first control unit. Therefore, when the second control unit takes over the drive control of the heating execution unit, the heating drive PWM period of the second control unit and the first control unit are consistent, which helps to ensure that the period of the drive signal remains unchanged before and after the control mode switch, thereby making the switching process smoother.

[0041] Furthermore, the preset wind speed threshold can be set to the wind speed value corresponding to level 6 wind speed. When the filtered wind speed signal reaches the preset wind speed threshold, it indicates that the environment of the target pipeline has experienced a strong wind disturbance that is sufficient to significantly aggravate the heat dissipation of the pipeline. At this time, it is determined that the transient operating condition triggering condition is met, and the system switches from steady-state temperature closed-loop control to transient control in order to respond promptly to the aggravated heat dissipation caused by the strong wind disturbance and avoid delay in protection action due to the lag in the response of the temperature sensor. Through the above method, the system can use the filtered wind speed signal as the judgment basis when a strong wind disturbance occurs to determine the transition to transient operating condition in a timely and accurate manner, thereby improving the advance and timely response of antifreeze protection and reducing the risk of false triggering caused by instantaneous wind speed fluctuations.

[0042] Specifically, the determination method for triggering the windless extreme cold includes: detecting the wind speed signal of the environment where the target pipeline is located; when the wind speed signal is less than the preset wind level threshold, determining whether the heating execution unit is in full power output state for two consecutive heating drive PWM cycles; if the heating execution unit is in full power output state for two consecutive PWM cycles, it is determined that the transient operating condition triggering condition is met, wherein the heating drive PWM cycle of the output drive signal of the first control unit and the second control unit is the same.

[0043] In actual operation, the meteorological conditions faced by pipeline antifreeze are not limited to strong wind disturbances. When there is no strong wind in the environment where the target pipeline is located, but the ambient temperature remains low, the temperature difference between the pipeline and the surrounding environment increases, and the pipeline heat dissipation will continue to intensify. At this time, since there is no strong wind signal, the strong wind disturbance triggering method will not be activated. However, if the protection action is triggered solely by the temperature threshold, there will still be a problem of temperature sensor response lag. More importantly, in windless and extremely cold conditions, the system may already be in a high heating output state. If the heating output remains at a high level for a long time and the pipeline temperature does not rise, it indicates that relying solely on steady-state temperature closed-loop control is insufficient to cope with the current heat dissipation state. In this case, it is necessary to determine the transition to a transient state through another triggering method. Therefore, it is necessary to set up an independent triggering determination method for windless and extremely cold scenarios.

[0044] In this embodiment, the determination method for windless extreme cold triggering includes: First, detecting the wind speed signal of the environment where the target pipeline is located. The purpose of detecting the wind speed signal is to eliminate strong wind disturbances, that is, to confirm that the current situation does not belong to the scenario targeted by the aforementioned strong wind disturbance triggering, thereby avoiding duplicate determination between the two triggering methods; Second, when the wind speed signal does not reach the preset wind level threshold, it is determined whether the heating execution unit is in full power output state for two consecutive PWM cycles. Under the premise of no strong wind signal, if the heating execution unit has been in full power output state for two consecutive complete PWM cycles, it indicates that the system has been continuously heating at maximum capacity under the current heat dissipation conditions, but the heat dissipation of the pipeline is still increasing, and the steady-state temperature closed-loop control is no longer able to meet the antifreeze requirements. Specifically, two consecutive PWM cycles are used as the determination method. The condition is set to avoid erroneous triggering of transient conditions due to instantaneous fluctuations within a single control cycle, ensuring the judgment result remains stable over time. Finally, if the heating execution unit is in full-power output state for two consecutive PWM cycles, the transient condition triggering condition is determined to be met. At this point, the system switches from steady-state temperature closed-loop control to transient control, so as to respond promptly to the continuous increase in heat dissipation under windless and extremely cold conditions through subsequent transient power adjustment and net heat loss accumulation warning. Through the above methods, the system can set an independent triggering judgment method for windless and extremely cold scenarios, in addition to triggering by strong wind disturbances, avoiding the problem of not being able to enter transient control in time due to the absence of strong wind signals. This expands the applicability of the transient condition triggering condition and improves the timeliness and reliability of antifreeze protection in windless and extremely cold scenarios.

[0045] 203. Calculation of cumulative net heat loss.

[0046] Specifically, the real-time heat dissipation parameters of the target pipeline are acquired using the second control unit. These parameters include the ambient temperature and wind speed of the environment in which the target pipeline is located, as well as the pipeline temperature, the temperature of the medium inside the pipeline, and the flow velocity of the medium inside the pipeline. Based on these real-time heat dissipation parameters, the real-time net heat loss power of the target pipeline is calculated. and the real-time net heat loss power Integrate over time to obtain the cumulative net heat loss. .

[0047] In this embodiment, after determining that the transient operating condition triggering condition is met, the second control unit needs to calculate the net heat loss accumulation as the basis for subsequent control mode switching and graded early warning. Specifically, the second control unit obtains the real-time heat dissipation parameters of the target pipeline. The real-time heat dissipation parameters reflect the actual heat dissipation state of the target pipeline at the current moment, including the ambient temperature and ambient wind speed of the environment where the target pipeline is located, as well as the pipeline temperature, the temperature of the medium inside the pipe, and the flow rate of the medium inside the pipe. Among them, the ambient temperature and ambient wind speed are used to characterize the heat dissipation conditions on the environmental side where the target pipeline is located. The lower the ambient temperature, the better. The higher the ambient wind speed, the stronger the convective heat transfer between the pipe and the environment, and the higher the pipe's heat dissipation rate. Pipe temperature characterizes the temperature state of the target pipe itself; the difference between the pipe temperature and the target temperature affects the rate at which the pipe dissipates heat to the environment. The temperature and flow velocity of the medium inside the pipe characterize the heat transfer conditions on the medium side of the target pipe. The medium temperature affects the heat exchange between the medium and the pipe wall, while the flow velocity affects the convective heat transfer efficiency within the medium. These parameters, from the environmental side, the pipe wall side, and the medium side respectively, collectively reflect the actual heat dissipation state of the target pipe, and are therefore used to calculate the real-time net heat loss power. The basis for this.

[0048] After obtaining the real-time heat dissipation parameters, the real-time net heat loss power of the target pipeline is calculated based on these parameters. Real-time net heat loss power This refers to the net heat loss power of the target pipeline per unit time at the current moment. Specifically, it can be determined by the heat dissipation loss of the target pipeline's outer surface based on the ambient temperature and wind speed, the heat exchange state inside the pipeline based on the difference between the pipeline temperature and the temperature of the medium inside the pipeline, and the influence of the medium flow rate on heat exchange based on the flow velocity inside the pipeline. Thus, the real-time net heat loss power of the target pipeline at the current moment can be obtained comprehensively. Unlike judging the degree of heat loss simply based on pipe temperature, real-time net heat loss power... It can reflect the actual heat dissipation intensity of the target pipeline from the perspective of heat transfer.

[0049] In one implementation, the real-time net heat loss power The calculation can be simplified based on the following assumptions: When the medium inside the pipe is still air, the thermal resistance of the air is high, and the heat transfer power between the air and the pipe wall is low, having a negligible impact on the net heat loss calculation; when the temperature of the medium inside the pipe is equal to the set temperature of the protective layer, the net heat exchange between the medium inside the pipe and the pipe wall is zero, and the calculation of net heat loss only needs to consider the heat dissipation from the protective layer to the atmosphere; the higher the temperature of the medium inside the pipe, the greater the internal heat transfer from the medium to the pipe wall, and the smaller the required electric heating power under steady state. However, under short-term wind-cold disturbances, the temperature of the medium inside the pipe remains basically unchanged, and the internal heat source can be considered as a fixed bias that does not change with the transient process, thus not affecting the calculation of the transient heat loss increment; through the above simplifications, the real-time net heat loss power... The calculation can focus on the heat dissipation of the protective layer to the atmosphere, which facilitates the rapid determination of net heat loss power under transient conditions and subsequent integration calculations.

[0050] Obtain the real-time net heat loss power Then, by integrating the real-time net heat loss power over time, the cumulative net heat loss is obtained. Since the heat dissipation of the target pipe is a cumulative process over time, the real-time net heat loss power... It can only reflect the heat dissipation intensity at the current moment, but cannot reflect the cumulative heat loss of the target pipeline over a period of time. This is achieved by analyzing the real-time net heat loss power. Integrate over time to obtain the cumulative net heat loss. It can convert the instantaneous heat dissipation intensity that changes over time into cumulative heat loss, thereby quantifying the actual heat loss of the target pipeline over a period of time, and the net cumulative heat loss. It can reflect the total amount of heat lost in the target pipeline, and also provide information for subsequent switching thresholds. Maximum permissible heat loss threshold The comparison provides a unified quantitative basis for determining whether to switch control modes and whether to output graded warning signals; based on this, the net heat loss accumulation... It can reflect the actual heat loss of the target pipeline from the perspective of heat accumulation, avoiding the delay in protection action caused by the lag in the response of temperature sensors when relying solely on temperature thresholds. This provides an accurate and quantitative basis for subsequent control mode switching and graded early warning.

[0051] 204. Drive control switching.

[0052] Specifically, the output level of the second control unit is adjusted to be consistent with the current output level of the first control unit; the drive output of the first control unit to the heating execution unit is stopped, and the second control unit is switched to output a drive signal to the heating execution unit, while maintaining the on / off state of the heating execution unit unchanged during the switching process.

[0053] In this embodiment, when the net heat loss accumulation reaches the switching threshold, the drive control of the heating execution unit needs to be switched from the first control unit to the second control unit. Since the first control unit and the second control unit are respectively connected to the heating execution unit, if the switching process is not handled properly, problems such as two drive signals acting on the heating execution unit at the same time, momentary interruption of drive output, or output level jump may occur, which will affect the normal operation of the heating execution unit and even cause the antifreeze protection to be interrupted. Therefore, the switching process needs to be executed in a predetermined order to ensure the smoothness of the switching and the continuity of the antifreeze protection.

[0054] In one implementation, firstly, the output level of the second control unit is adjusted to match the current output level of the first control unit. Before the switch, the heating execution unit is driven and controlled by the first control unit, and its output level corresponds to the current heating output state. If the drive output is directly switched from the first control unit to the second control unit, and the output level of the second control unit is inconsistent with that of the first control unit, the drive signal received by the heating execution unit will jump at the moment of switching, which may cause a sudden change in the heating output. By first adjusting the output level of the second control unit to match the current output level of the first control unit, the two drive outputs are kept at the same level before the switch, thereby providing a smooth transition condition for the subsequent switch and avoiding the impact on the heating execution unit due to the level difference at the moment of switching.

[0055] Secondly, the first control unit stops driving the heating execution unit and switches to the second control unit to output driving signals to the heating execution unit. Since the output level of the second control unit is now consistent with the current output level of the first control unit, the driving signal received by the heating execution unit will not change during the process of the first control unit stopping driving and the second control unit taking over driving. In other words, the driving signal received by the heating execution unit remains consistent in level before and after the switch, only the driving source changes from the first control unit to the second control unit.

[0056] Meanwhile, the on / off state of the heating execution unit remains unchanged during the switching process. The on / off state refers to whether the heating execution unit is in a heating state before and after the switching, and its corresponding on / off status. By maintaining the on / off state of the heating execution unit during the switching process, a driving gap can be avoided between the first control unit stopping driving and the second control unit taking over driving, preventing power outages or heating interruptions in the heating execution unit at the moment of switching, thus ensuring the continuity of antifreeze protection. Therefore, the switching process is completed under the premise that the heating execution unit maintains its original on / off state. After the switching is completed, the second control unit continues to drive and control the heating execution unit. Through the above method, the process of switching drive control from the first control unit to the second control unit can be completed under the condition of consistent output level and unchanged on / off state, avoiding drive signal jumps or heating interruptions at the moment of switching, thereby ensuring the smoothness of the switching process and the continuity of antifreeze protection.

[0057] 205. Transient power regulation and graded early warning.

[0058] Specifically, the real-time net heat loss power of the target pipe is determined based on real-time heat dissipation parameters. Determine the device type of the heating actuator; if the heating actuator is a stepless power regulation device, then control the output power of the heating actuator to follow the real-time net heat loss power. The changes should be synchronized and not exceed the rated maximum power of the heating actuator; if the heating actuator is a graded adjustment device, the changes should be based on the real-time net heat loss power. Based on the comparison results with the power of each level of the heating actuator, the output power of the heating actuator is controlled to increase or decrease step by step.

[0059] In this embodiment, when the second control unit drives the heating execution unit, it needs to adjust the output power of the heating execution unit according to the real-time heat dissipation parameters. Since the power adjustment methods of heating execution units used in different sites may differ—some heating execution units support continuously adjustable output power, while others can only be adjusted according to preset levels—if a uniform power adjustment method is used, some heating execution units may not be able to adjust according to the actual heat dissipation state, affecting the matching degree between the heating output and the actual heat dissipation state of the pipeline. Therefore, before performing power adjustment, it is necessary to first determine the real-time net heat loss power of the target pipeline. The appropriate power adjustment method is adopted according to the equipment type of the heating execution unit.

[0060] In one implementation, firstly, the real-time net heat loss power of the target pipe is determined based on real-time heat dissipation parameters. Real-time net heat loss power This parameter reflects the actual heat dissipation intensity of the target pipeline at the current moment and serves as the basis for subsequent power adjustment. The specific determination method can refer to the aforementioned real-time heat dissipation parameters and real-time net heat loss power. The calculation process will not be elaborated here; secondly, the device type of the heating execution unit is determined. The device type is used to characterize the power adjustment method supported by the heating execution unit. It can be determined according to the hardware configuration, drive circuit form or control interface form of the heating execution unit. By determining the device type, the subsequent power adjustment method can be matched with the actual adjustment capability of the heating execution unit, avoiding control failure due to mismatch between the adjustment method and the device type.

[0061] If the heating actuator is a stepless power regulation device, then the output power of the heating actuator should follow the real-time net heat loss power. The output power of a stepless power regulating device is a heating actuator whose output power can be continuously varied within the regulating range, and does not exceed the rated maximum power of the heating actuator. For this type of device, the output power follows the real-time net heat loss power. Synchronous changes allow the heating output to dynamically match the actual heat dissipation state of the target pipe, i.e., when the real-time net heat loss power... When the power is increased, the output power is increased accordingly; when the real-time net heat loss power is increased... When the output power is reduced, the output power is reduced accordingly. Thus, the heating output can meet the antifreeze requirements and avoid the waste of electricity caused by outputting high power when the heat dissipation requirements are small. At the same time, limiting the output power to within the rated maximum power can prevent the heating actuator from being affected by overload operation, thus ensuring its safety and service life.

[0062] If the heating actuator is a graded adjustment device, then based on the real-time net heat loss power... Based on the comparison results of the power levels of the heating actuator, the output power of the heating actuator is controlled to gradually increase or decrease. A graded-level adjustable device refers to a heating actuator whose output power can only be adjusted according to a few preset levels. For this type of device, the real-time net heat loss power is... By comparing the power of each gear, the target gear corresponding to the current heat dissipation state can be determined. Then, the output power is controlled to increase or decrease step by step to the target gear. By adopting a step-by-step adjustment method, the impact of gear jumps on the heating execution unit and the thermal state of the pipeline can be avoided, making the heating output change process more stable.

[0063] This application enables different types of heating actuators to adjust their power according to the real-time heat dissipation status of the target pipeline, thereby matching the heating output with the actual heat dissipation requirements, meeting the antifreeze requirements while taking into account operating energy consumption, and improving the adaptability between the power adjustment process and the adjustment capability of the heating actuator.

[0064] 206. Exit transient state and restore steady-state control.

[0065] Specifically, when the net heat loss accumulates Below the switching threshold And if the net heat loss accumulates during the preset duration... The switching threshold has been reached again. Then the heating execution unit is maintained under the drive of the second control unit; if the net heat loss accumulates... The switching threshold was not reached again. If the output level of the first control unit is adjusted to match the current output level of the second control unit, the second control unit stops driving the heating execution unit, and the first control unit outputs a drive signal to the heating execution unit, maintaining the on / off state of the heating execution unit during the switching process; after the first control unit resumes driving control of the heating execution unit, the net heat loss accumulation is calculated. The temperature is reset to zero, and the heating actuator is driven by the first control unit to perform steady-state temperature closed-loop control.

[0066] In this embodiment, when the net heat loss accumulates... Below the switching threshold When the preset duration is reached, it indicates that the net heat loss of the target pipeline has decreased, the transient condition is easing, and the system can prepare to switch from transient control back to steady-state temperature closed-loop control. However, the easing of the transient condition does not necessarily mean that it has stabilized and ended. If the accumulated net heat loss... If the temperature only drops briefly and then rises again, it indicates that the transient condition has not truly eased. If transient control is prematurely discontinued at this point, the system may frequently switch control modes when the transient condition recurs, affecting control stability and the continuity of antifreeze protection. Therefore, before discontinuing transient control, it is necessary to first assess the cumulative net heat loss. Confirm the changing trend and process accordingly based on the confirmation results.

[0067] Specifically, when the net heat loss accumulates Below the switching threshold And if the net heat loss accumulates during the preset duration... The switching threshold has been reached again. Then the heating execution unit is still driven and controlled by the second control unit, which means that although the net heat loss accumulates... It once fell below the switching threshold. It remained in effect for the preset duration, but if it subsequently reached the switching threshold again... This indicates that the heat dissipation status of the target pipeline has not yet stabilized and the transient condition may reappear. In this case, the system continues to be driven and controlled by the second control unit to control the heating execution unit, without performing a switch-out, thus avoiding repeated switching due to premature exit from transient control; if the net heat loss accumulates... The switching threshold was not reached again. This indicates that the transient condition has indeed eased, and at this point, the switch from transient control to steady-state control is executed. Specifically, the output level of the first control unit is first adjusted to be consistent with the current output level of the second control unit. Before the switch, the heating execution unit is driven and controlled by the second control unit, and its output level corresponds to the current heating output state. If the drive output is directly switched from the second control unit to the first control unit, and the output level of the first control unit is inconsistent with that of the second control unit, the drive signal received by the heating execution unit will jump at the moment of switching, which may cause a sudden change in the heating output. By first adjusting the output level of the first control unit to be consistent with the current output level of the second control unit, the two drive outputs are kept at the same level before the switch, thereby providing a smooth transition condition for the subsequent switch.

[0068] Afterwards, the second control unit stops driving the heating execution unit, and the first control unit outputs a drive signal to the heating execution unit. Since the output level of the first control unit is now consistent with the current output level of the second control unit, the drive signal received by the heating execution unit will not change during the process of the second control unit stopping driving and the first control unit taking over driving. At the same time, the on / off state of the heating execution unit remains unchanged during the switching process, avoiding a driving gap between the second control unit stopping driving and the first control unit taking over driving, preventing the heating execution unit from losing power or interrupting heating at the moment of switching, thereby ensuring the continuity of antifreeze protection.

[0069] Finally, after the first control unit resumes drive control of the heating actuator, the net heat loss accumulation is calculated. In another implementation, zeroing out involves simultaneously recording the real-time net heat loss power. The data is reset to zero, and the first control unit drives the heating execution unit to perform steady-state temperature closed-loop control. The data reset is specifically considered because both data are intermediate quantities calculated based on real-time heat dissipation parameters during the transient process, representing the instantaneous heat dissipation intensity and accumulated heat loss under transient conditions, respectively. If they are not reset upon exiting, the accumulated heat loss in the previous transient process and the net heat loss power at the previous moment may have a residual impact on subsequent judgments, preventing the judgment of subsequent transient conditions from restarting from a new starting state. Therefore, before resuming steady-state control, the real-time net heat loss power is reset. and cumulative net heat loss All data is reset to zero, thus affecting the triggering of subsequent transient conditions and the accumulation of net heat loss. Both calculations and tiered early warnings restart from a new initial state. After resetting, the first control unit re-acquires the pipe temperature of the target pipe and adjusts the drive signal output to the heating actuator based on the temperature deviation between the pipe temperature and the preset target temperature, causing the target pipe to re-enter steady-state temperature closed-loop control. Through this method, the system can smoothly recover to steady-state temperature closed-loop control after the transient condition eases, avoiding premature exit from transient control before the transient condition has truly subsided. During the exit process, the on / off state of the heating actuator remains unchanged, while simultaneously resetting the real-time net heat loss power. and cumulative net heat loss This avoids residual effects of the previous transient process on subsequent judgments, thus balancing the stability of the control process, the continuity of antifreeze protection, and operating energy consumption.

[0070] In another optional implementation, the pipeline antifreeze control system may further include a threshold adaptive adjustment unit. In actual operation, the actual operating conditions of the target pipeline environment may change over time. For example, seasonal weather conditions, changes in pipeline insulation status, and differences in the ratio of buried to exposed sections may all lead to deviations between the actual heat dissipation state and the preset conditions. If the maximum allowable heat loss threshold... Using a fixed setting may lead to inappropriate threshold settings when operating conditions drift, especially when the maximum allowable heat loss threshold is... When the setting is too high, the net heat loss accumulation The threshold may not be reached before the actual danger occurs, resulting in untimely early warning output and the risk of missed alarms.

[0071] Specifically, the threshold adaptive adjustment unit can record operating data under multiple historical operating conditions, and the operating data may include net heat loss power. Net heat loss cumulative amount And at least one of the following: pipeline temperature change data, such as the net heat loss power recorded under multiple historical high wind cooling conditions. Net heat loss cumulative amount And pipeline temperature change data, and from this, determine the cumulative heat loss data before the actual danger occurs. The cumulative heat loss data before the actual danger occurs can refer to the net cumulative heat loss before the pipeline temperature approaches the freezing blockage danger value. The achieved value is based on the cumulative heat loss data and the maximum allowable heat loss threshold. Perform iterative corrections to achieve the corrected maximum allowable heat loss threshold. It can more accurately reflect the actual degree of heat loss under the current on-site operating conditions, thereby providing early warning signals in subsequent operation and reducing the impact of the maximum allowable heat loss threshold. Risk of missed alarms due to improper settings; the threshold adaptive adjustment unit adjusts the maximum allowable heat loss threshold. It can adaptively adjust based on historical operating data, thereby adapting to changes in environmental conditions and improving performance due to the maximum allowable heat loss threshold. This addresses the issue of missed alarms caused by inappropriate parameters and improves the reliability of early warning systems under different field conditions.

[0072] This application provides a specific embodiment of a pipeline antifreeze control method, applied to a DN50 pipeline antifreeze branch line. Specifically, the pipeline is a 20# seamless steel pipe with an outer diameter D. i =0.0603m, wall thickness is 3.91mm, unit length mass is 5.44kg / m, total length is 300m, of which the open-air laying section is 180m long, which is the weak and risky section of the pipeline and is completely exposed to the atmospheric environment; the buried laying section is 120m long, the top of the pipe is buried at a depth of about 1.2m, and the heat loss of the buried laying section is basically unchanged; the pipeline is equipped with a mineral wool insulation layer with an insulation thickness δ=50mm, and an outer insulation aluminum skin is installed on the outside. The outer diameter of the insulation layer and the outer aluminum skin is Do=0.1603m, and the thermal conductivity of the insulation material is λ=0.040W / (m·K).

[0073] Furthermore, the heating actuator of the pipeline antifreeze control system is compatible with both graded level adjustment and stepless zero-crossing adjustment power regulation methods. The rated power of the electric heat tracing hardware is 25W / m, and the total rated power is 7.5kW. The first control unit and the second control unit in the pipeline antifreeze control system are respectively connected to the heating actuator.

[0074] Based on this, the current calculation parameters specifically include: the outer diameter D of the steel pipe. i =0.0603m, outer diameter of the insulation outer cladding Do=0.1603m, thermal conductivity of the insulation material λ=0.040W / (m·K); KF is the surface convective heat transfer coefficient of the aluminum outer cladding facing the atmosphere, in W / (m²). 2 ·K), under windless conditions, KF1=6W / (m 2 ·K), under strong wind conditions, KF2=20W / (m 2 ·K); The target pipe wall temperature is 5℃, and the ambient temperature is 20℃, temperature difference ΔT = 25K; calculated length L of the open-air section 露天 =180m; instantaneous wind speed under strong wind conditions can reach 12m / s.

[0075] In this embodiment, real-time net heat loss power The thermal resistance can be determined based on the target pipeline's thermal resistance model. This model includes the internal convective thermal resistance from the medium inside the pipe to the pipe wall, the conductive thermal resistance formed by the pipe wall and insulation layer, and the convective thermal resistance from the outer surface of the insulation layer to the environment. The temperature difference between the ambient temperature and the pipeline temperature serves as the driving force for heat transfer. Ambient wind speed affects the external convective thermal resistance, while the flow velocity of the medium inside the pipe affects the internal convective thermal resistance. Based on this, the heat dissipation power of the open-air section in this embodiment is calculated as follows: Specifically, under stable and windless weather conditions, the system operates in a steady-state state. The first control unit drives the heating actuator to perform steady-state temperature closed-loop control on the target pipeline. The steady-state calculation incorporates the real-time net heat loss power of the open-air section. First, calculate the heat dissipation power of the open-air section:

[0076] Meanwhile, the actual output power of electric heat tracing under thermal steady state .

[0077] Therefore, the following calculation is performed:

[0078] This difference corresponds to the heat dissipation and electric heat tracing efficiency loss in the buried section.

[0079] Under sudden weather changes such as strong winds and temperature drops, the system enters a transient state. Regardless of whether the heating actuator is a stepped-level regulating device or a stepless zero-crossing regulating device, it immediately determines the real-time net heat loss power based on real-time heat dissipation parameters and participates in the power regulation decision. At the same time, it runs the net heat loss accumulation in parallel. Points-based warning.

[0080] Specifically, the heat dissipation capacity of the open-air section is:

[0081] Therefore, the increase in heat dissipation power of the exposed laying section under high wind conditions, i.e., the real-time net heat loss power, can be calculated as follows:

[0082] Meanwhile, the heat dissipation and electric heat tracing efficiency loss of the buried section remain unchanged, while the electric heat tracing output is simultaneously increased to:

[0083] In addition, the switching threshold for net heat loss accumulation and maximum allowable heat loss threshold Calculations are only performed on the 180m exposed high-risk pipe section; the heat loss of the buried section remains basically unchanged and is not included in the integration calculation, with the specific heat capacity C of the pipe material taken as 470 J / (kg·℃); the total mass M of the exposed pipeline... 露天 =5.44×180=979.2kg; Switching threshold The allowable temperature drop for the corresponding open-air pipe section is from 5℃ to 2℃, a total drop of 3℃. The switching threshold is calculated based on this.

[0084] Maximum permissible heat loss threshold For the corresponding open-air pipe section, the allowable temperature drop is from 5℃ to 0℃, and the drop is 5℃:

[0085] Among them, the maximum allowable heat loss threshold Greater than the switching threshold .

[0086] In a verification example, the same basic conditions as in the above embodiments were used for the pipeline, i.e., the pipeline was DN50 and the outer diameter of the steel pipe was D. i =0.0603m, outer diameter of the insulation outer lining Do=0.1603m, thermal conductivity of the mineral wool insulation layer λ=0.040W / (m·K), calculated length of the open-air section L 露天 =180m; The surface convective heat transfer coefficient of the aluminum outer cladding facing the atmosphere is KF1=6W / (m²) under windless conditions. 2 ·K), under high wind conditions, KF2=20W / (m 2 ·K); In addition, the medium inside the pipe is water at 10℃, and the pipe wall temperature is approximately taken as the temperature of the medium inside the pipe, T. pipe =10℃.

[0087] Based on this, the fixed thermal resistance term is first calculated, where the thermal resistance of the insulated cylinder is:

[0088] The external convective thermal resistance under windless conditions is:

[0089] Therefore, the total thermal resistance under stable, windless weather conditions is:

[0090] The convective thermal resistance on the outer side under high wind conditions is:

[0091] Therefore, the total thermal resistance under high wind conditions is:

[0092] In this verification example, the medium inside the pipe is water at 10℃, and the pipe wall temperature is T. pipe =10℃, ambient temperature is At 20℃, the temperature difference is ΔT = 30K.

[0093] Under stable, windless weather conditions, the heat dissipation power per unit length is:

[0094] The heat dissipation capacity of the open-air section is:

[0095] However, under conditions of sudden weather changes and strong winds, the ambient temperature remains... At 20℃, with only an increase in ambient wind speed, the heat dissipation power per unit length is:

[0096] The heat dissipation capacity of the open-air section is:

[0097] Therefore, the increase in heat dissipation power of the exposed laying section under high wind conditions, i.e., the real-time net heat loss power, can be calculated as follows:

[0098] In another verification example, the medium inside the pipe is water at 10°C, and the pipe wall temperature is T. pipe =10℃, ambient temperature under windless steady-state operating conditions is 15℃, ambient temperature under strong wind and rapid change conditions is 20℃. Under windless steady-state conditions, the temperature difference is ΔT1=10℃. ( 15) = 25K, the temperature difference under the condition of strong wind and rapid change is ΔT2 = 10 ( 20) = 30K; Based on this, under stable and windless weather conditions, the heat dissipation power per unit length is:

[0099] The heat dissipation capacity of the open-air section is:

[0100] Under conditions of sudden weather changes, strong winds, and temperature drops, the ambient wind speed increases and the ambient temperature decreases. At 20℃, the heat dissipation power per unit length is:

[0101] The heat dissipation capacity of the open-air section is:

[0102] Therefore, the increase in heat dissipation power of the outdoor laying section under strong wind cooling conditions, i.e., the real-time net heat loss power, can be calculated as follows:

[0103] As can be seen from the above verification examples, under the condition of only increased ambient wind speed, the increase in heat dissipation power in the open-air section is 74.30W; under the dual disturbance condition of increased ambient wind speed and decreased ambient temperature, the increase in heat dissipation power in the open-air section reaches 287.51W, which is significantly greater than that under the condition of single wind speed disturbance; the above results further indicate that the real-time net heat loss power It can reflect the heat dissipation increment of the target pipeline under different operating conditions based on real-time heat dissipation parameters, thereby providing a basis for transient power compensation control and net heat loss accumulation. The calculations provide the basis.

[0104] Furthermore, as Figure 1 In terms of specific implementation of the method, this application provides a pipeline antifreeze control system, such as... Figure 3 As shown, the system includes: a first control unit, a second control unit, and a heating execution unit; the first control unit is used to drive and control the heating execution unit to perform steady-state temperature closed-loop control on the target pipeline under steady-state operating conditions; the second control unit is used to calculate the net heat loss accumulation based on the real-time heat dissipation parameters of the target pipeline when the transient operating condition triggering condition is met, and drive and control the heating execution unit when the net heat loss accumulation reaches the switching threshold; the second control unit is also used to adjust the output power of the heating execution unit according to the real-time heat dissipation parameters when driving and controlling the heating execution unit, and compare the net heat loss accumulation with the preset maximum allowable heat loss threshold, and output a graded early warning signal; the first control unit is also used to drive and control the heating execution unit to perform steady-state temperature closed-loop control when the net heat loss accumulation is lower than the switching threshold and continues for a preset duration.

[0105] Specifically, Figure 3 The first control unit and the second control unit are connected to the heating execution unit by selectively switching on one of them, so that the heating execution unit is driven and controlled by one of the first control unit and the second control unit at the same time, and the control unit is switched from one control unit to the other control unit when the corresponding conditions are met.

[0106] In one embodiment, the pipeline antifreeze control system further includes a temperature sensor and a wind speed sensor. The signals from the temperature sensor and the wind speed sensor are respectively connected to the acquisition ports of the first control unit and the second control unit, enabling both the first control unit and the second control unit to acquire real-time heat dissipation parameters such as the pipe temperature, ambient temperature, ambient wind speed, and the temperature and flow rate of the medium inside the pipe. The output terminal of the first control unit is connected to one input terminal of an analog switch, and the output terminal of the second control unit is connected to the other input terminal of the analog switch. The output terminal of the analog switch is connected to the heating execution unit. The analog switch can be a 74HC4053 analog switch, used to isolate and switch the drive output between the first control unit and the second control unit. The first control unit and the second control unit can communicate and interact to transmit operating status indicators to each other. The second control unit can also output alarm signals to the alarm output interface to output graded warning signals.

[0107] Under steady-state conditions, the environmental meteorological conditions are relatively stable, and the system is in a steady-state operating state. The temperature control mode is adopted. Specifically, the first control unit collects the pipeline temperature and outputs a PWM drive signal to control the heating execution unit to perform steady-state temperature closed-loop control on the target pipeline. The second control unit only completes signal acquisition and monitoring and does not take over the drive control of the heating execution unit. At this time, the analog switch connects the control path of the first control unit to the heating execution unit.

[0108] Under transient conditions, such as a sudden strong wind or a rapid increase in pipe heat dissipation, the system enters a transient process. The second control unit reads the pipe temperature, ambient temperature, wind speed, pipe medium temperature, and pipe medium flow rate in real time, and calculates the real-time net heat loss power based on these real-time heat dissipation parameters. ; Real-time net heat loss power Integrate over time to obtain the cumulative net heat loss. ; cumulative net heat loss With the preset maximum allowable heat loss threshold Continuous comparison; if net heat loss accumulates It continues to accumulate and approaches the maximum allowable heat loss threshold. The system outputs a Level 1 warning; when the cumulative net heat loss... Reaching or exceeding the maximum permissible heat loss threshold When this occurs, a level two alarm signal is output.

[0109] Net heat loss accumulation Once the switching threshold is reached, the second control unit takes over the drive control of the heating actuator via an analog switch. Specifically, the analog switch achieves high-impedance isolation and switching between the steady-state control path of the first control unit and the transient control path of the second control unit: during steady-state normal operation, the control path of the first control unit to the heating actuator is activated; when a transient trigger condition occurs, drive control switching is executed, and the second control unit performs power compensation control on the heating actuator to avoid mutual interference between the two signals. (The last sentence appears to be incomplete and possibly refers to a separate point about net heat loss accumulation.) After the temperature drops below the switching threshold and remains below the preset time, the analog switch reconnects the control path of the first control unit to the heating execution unit, and the first control unit drives the heating execution unit to perform steady-state temperature closed-loop control.

[0110] It should be noted that other corresponding descriptions of the functional units involved in the pipeline antifreeze control system provided in this embodiment can be found in [reference needed]. Figure 1 and Figure 2 The corresponding descriptions in [the document] will not be repeated here.

[0111] Based on the above, Figure 1 and Figure 2 Accordingly, this embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements the above-described pipeline antifreeze control method.

[0112] Based on this understanding, the technical solution of this application can be embodied in the form of a software product. The software product to be identified can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, mobile hard drive, etc.) and includes several instructions to enable a computer device (such as a personal computer, server, or network device, etc.) to execute the pipeline antifreeze control method of various implementation scenarios of this application.

[0113] Based on the above, Figure 1 and Figure 2 The method shown, and Figure 3 The illustrated embodiment of the pipeline antifreeze control system, in order to achieve the above objectives, such as... Figure 4 As shown, this embodiment also provides a physical device for a pipeline antifreeze control method. This device includes a communication bus, a processor, a memory, and a communication interface. It may also include input / output interfaces and a display device. The various functional units can communicate with each other via the bus. The memory stores a computer program, and the processor executes the program stored in the memory to perform the pipeline antifreeze control method described in the above embodiment.

[0114] Optionally, the physical device may also include a user interface, a network interface, a camera, radio frequency (RF) circuitry, sensors, audio circuitry, a Wi-Fi module, etc. The user interface may include a display screen, input units such as a keyboard, etc., and optional user interfaces may also include USB interfaces, card reader interfaces, etc. The network interface may optionally include standard wired interfaces, wireless interfaces (such as Wi-Fi interfaces), etc.

[0115] Those skilled in the art will understand that the physical equipment structure of the pipeline antifreeze control method provided in this embodiment does not constitute a limitation on the physical equipment, and may include more or fewer components, or combine certain components, or have different component arrangements.

[0116] The storage medium may also include an operating system and a network communication module. The operating system is a program that manages the hardware and software resources of the aforementioned physical device, supporting the operation of information processing programs and other software and / or programs to be identified. The network communication module is used to enable communication between the various components within the storage medium, as well as communication with other hardware and software in the information processing physical device.

[0117] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms, or it can be implemented by hardware. By applying the technical solution of this application, firstly, under steady-state operating conditions, the first control unit drives and controls the heating execution unit to perform steady-state temperature closed-loop control on the target pipeline, so that the pipeline can maintain a stable antifreeze state in a temperature closed-loop manner when the meteorological conditions are relatively stable, avoiding the problem of increased control deviation due to changes in operating conditions when relying solely on power control, thus improving the stability and reliability of pipeline temperature control; secondly, when the transient operating condition triggering condition is met, the net heat loss accumulation is calculated based on the real-time heat dissipation parameters of the target pipeline, and when the net heat loss accumulation reaches the switching threshold, the control unit is switched to be driven and controlled by the second control unit, so that the antifreeze control can switch from steady-state temperature closed-loop control to transient control in a timely manner when the operating conditions change dynamically, no longer relying solely on the temperature threshold to trigger the protection action, which is beneficial to improving the advance and response of the protection action. The method ensures timely response; subsequently, when the second control unit drives the heating execution unit, it adjusts the output power of the heating execution unit according to real-time heat dissipation parameters, and compares the net heat loss accumulation with the maximum allowable heat loss threshold to output graded early warning signals. This allows the heating output to be adjusted according to the actual heat dissipation state of the pipeline, avoiding direct output of heating power in a single mode when weather conditions change abruptly. This helps to achieve a balance between energy consumption control and antifreeze protection, and can output graded early warnings in advance when the net heat loss accumulation reaches the corresponding threshold, improving the timeliness of antifreeze protection. Finally, when the net heat loss accumulation is lower than the switching threshold and continues for a preset time, it switches to the first control unit driving the heating execution unit to perform steady-state temperature closed-loop control, so that the system can return to steady-state temperature closed-loop control after the transient condition is relieved, ensuring the stability of temperature control and operating energy consumption. The above method improves the response timeliness and control reliability of the pipeline antifreeze scheme and reduces operating energy consumption by coordinating steady-state temperature closed-loop control and transient control, as well as calculating the net heat loss accumulation based on real-time heat dissipation parameters, adjusting power, and providing graded early warnings.

[0118] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of a preferred embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing this application. Those skilled in the art will understand that the modules in the apparatus of the embodiment can be distributed within the apparatus of the embodiment as described, or can be modified to be located in one or more apparatuses different from this embodiment. The modules of the above-described embodiment can be combined into one module, or further divided into multiple sub-modules.

[0119] It should be noted that any AI models, software tools, or components not belonging to this company appearing in the embodiments of this application are merely illustrative examples and do not represent actual use. All user personal information involved in the embodiments of this application has been authorized (with the knowledge and consent) by the relevant parties or has been fully authorized by all parties, and the executing entity may obtain it through various legal and compliant means. The collection, storage, use, processing, transmission, provision, and disclosure of the information, data, and signals involved all comply with relevant laws and regulations and do not violate public order and good morals.

[0120] The serial numbers in this application are for descriptive purposes only and do not represent the superiority or inferiority of any particular implementation scenario. The above disclosures are merely a few specific implementation scenarios of this application; however, this application is not limited thereto, and any variations conceived by those skilled in the art should fall within the protection scope of this application.

Claims

1. A pipeline antifreeze control method, applied to a pipeline antifreeze control system, the pipeline antifreeze control system comprising a first control unit, a second control unit, and a heating execution unit, characterized in that, The method includes: Under steady-state conditions, the heating execution unit is driven and controlled by the first control unit to perform steady-state temperature closed-loop control on the target pipeline. When the transient operating condition triggering condition is met, the second control unit calculates the net heat loss accumulation based on the real-time heat dissipation parameters of the target pipeline. When the cumulative net heat loss reaches the switching threshold, the drive output of the heating execution unit is switched from the first control unit to the second control unit; During the period when the second control unit drives and controls the heating execution unit, the second control unit adjusts the output power of the heating execution unit according to the real-time heat dissipation parameters, compares the net heat loss accumulation with the preset maximum allowable heat loss threshold, and outputs a graded early warning signal. When the cumulative net heat loss is lower than the switching threshold and continues for a preset duration, the drive output of the heating execution unit is switched from the second control unit to the first control unit, and the first control unit drives and controls the heating execution unit to perform steady-state temperature closed-loop control.

2. The method according to claim 1, characterized in that, The transient operating condition triggering conditions include strong wind disturbance triggering, and the determination method for strong wind disturbance triggering includes: Collect wind speed signals of the environment where the target pipeline is located; The wind speed signal is filtered for two consecutive heating drive PWM cycles, wherein the heating drive PWM cycles of the output drive signals of the first control unit and the second control unit are the same. When the filtered wind speed signal is greater than or equal to the preset wind level threshold, it is determined that the transient operating condition triggering condition is met.

3. The method according to claim 1, characterized in that, The transient operating condition triggering conditions include windless extreme cold triggering, and the determination method for windless extreme cold triggering includes: Detect the wind speed signal of the environment in which the target pipeline is located; When the wind speed signal is less than the preset wind level threshold, it is determined whether the heating execution unit is in full power output state for two consecutive PWM cycles. If the heating execution unit is in full power output state for two consecutive heating drive PWM cycles, it is determined that the transient operating condition triggering condition is met, wherein the heating drive PWM cycles of the output drive signals of the first control unit and the second control unit are the same.

4. The method according to claim 1, characterized in that, The calculation of the net heat loss accumulation by the second control unit based on the real-time heat dissipation parameters of the target pipe includes: The second control unit obtains the real-time heat dissipation parameters of the target pipe, wherein the real-time heat dissipation parameters include the ambient temperature and ambient wind speed of the environment in which the target pipe is located, as well as the pipe temperature, the temperature of the medium inside the pipe, and the flow rate of the medium inside the pipe. The real-time net heat loss power of the target pipe is calculated based on the real-time heat dissipation parameters, and the real-time net heat loss power is integrated over time to obtain the cumulative net heat loss.

5. The method according to claim 1, characterized in that, Switching the drive output of the heating execution unit from the first control unit to the second control unit includes: Adjust the output level of the second control unit to match the current output level of the first control unit; The first control unit stops driving the heating execution unit and switches to the second control unit outputting a driving signal to the heating execution unit, while maintaining the on / off state of the heating execution unit unchanged during the switching process.

6. The method according to claim 1, characterized in that, The step of adjusting the output power of the heating execution unit by the second control unit according to the real-time heat dissipation parameters includes: The real-time net heat loss power of the target pipeline is determined based on the real-time heat dissipation parameters. Determine the device type of the heating execution unit; If the heating execution unit is a stepless power regulation device, then the output power of the heating execution unit is controlled to change synchronously with the real-time net heat loss power, and does not exceed the rated maximum power of the heating execution unit; If the heating execution unit is a graded adjustment device, then based on the comparison result between the real-time net heat loss power and the power of each grade of the heating execution unit, the output power of the heating execution unit is controlled to increase or decrease step by step.

7. The method according to claim 1, characterized in that, The maximum allowable heat loss threshold is greater than the switching threshold; when the cumulative net heat loss is lower than the switching threshold and continues for a preset duration, the drive output of the heating execution unit is switched from the second control unit to the first control unit, and the first control unit drives and controls the heating execution unit to perform steady-state temperature closed-loop control, including: When the cumulative net heat loss is lower than the switching threshold and continues for the preset duration, if the cumulative net heat loss reaches the switching threshold again, the heating execution unit will continue to be driven and controlled by the second control unit. If the net heat loss accumulation does not reach the switching threshold again, the output level of the first control unit is adjusted to be consistent with the current output level of the second control unit, the drive output of the second control unit to the heating execution unit is stopped, and the first control unit outputs a drive signal to the heating execution unit, and the on / off state of the heating execution unit remains unchanged during the switching process. After the first control unit resumes drive control of the heating execution unit, the net heat loss accumulation is cleared to zero, and the first control unit drives and controls the heating execution unit to perform steady-state temperature closed-loop control.

8. A pipeline antifreeze control system, characterized in that, include: The first control unit, the second control unit, and the heating execution unit; The first control unit is used to drive and control the heating execution unit to perform steady-state temperature closed-loop control on the target pipeline under steady-state operating conditions; The second control unit is used to calculate the net heat loss accumulation based on the real-time heat dissipation parameters of the target pipeline when the transient operating condition triggering condition is met; when the net heat loss accumulation reaches the switching threshold, it drives and controls the heating execution unit. The second control unit is also configured to adjust the output power of the heating execution unit according to the real-time heat dissipation parameters during the driving control of the heating execution unit, compare the net heat loss accumulation with the preset maximum allowable heat loss threshold, and output a graded warning signal; The first control unit is further configured to drive and control the heating execution unit to perform steady-state temperature closed-loop control when the net heat loss accumulation is lower than the switching threshold and continues for a preset duration.

9. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

10. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

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