A method and system for maintaining a constant temperature of exhaust pipe based on dynamic temperature adjustment

Abstract

This invention relates to the field of temperature control technology and proposes a method and system for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature regulation. The method includes: generating a proportional control component and an integral control component based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline; determining the heat load change trend of the exhaust gas pipeline over a certain period of time by using the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline, and generating a feedforward compensation component; adjusting the output power of the heating element in the exhaust gas pipeline using a dynamic temperature regulation command obtained by superimposing and fusing the proportional control component, the integral control component, and the feedforward compensation component, and calculating the residual deviation between the updated actual wall temperature value and the target constant temperature setpoint; this invention can improve the efficiency of maintaining constant temperature in an exhaust gas pipeline.

Description

Technical Field

[0001] This invention relates to the field of temperature control technology, and in particular to a method and system for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature regulation. Background Technology

[0002] Traditional constant temperature maintenance of exhaust gas pipelines relies solely on the difference between the real-time collected pipeline wall temperature and the target constant temperature setpoint for passive temperature control. It does not track, analyze, or predict the flow changes at the exhaust gas inlet, and cannot detect the rise and fall of heat load and fluctuations in advance. The temperature adjustment action always lags behind the actual changes in heat load. When the exhaust gas flow rate increases or decreases rapidly or fluctuates frequently, the pipeline wall temperature will quickly deviate from the target set range, and the control response speed cannot match the dynamic change rhythm of heat load.

[0003] Existing constant temperature control for exhaust gas pipelines only uses a basic real-time deviation adjustment method, which cannot integrate and correct the accumulated temperature deviation over multiple sampling periods. During steady-state operation, residual temperature deviations that cannot be eliminated will persist. At the same time, the adjustment of the heating element output power lacks graded levels and a hysteresis comparison mechanism, and the power adjustment is prone to frequent small jumps, resulting in continuous irregular oscillations in the pipeline wall temperature. The accuracy and stability of constant temperature maintenance are greatly reduced, and the exhaust gas pipeline cannot be guaranteed to maintain a stable constant temperature operation state in the long term. Summary of the Invention

[0004] This invention provides a method and system for maintaining constant temperature in exhaust gas pipelines based on dynamic temperature control, in order to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides a method for maintaining a constant temperature in an exhaust gas pipeline based on dynamic temperature control, comprising: Itm1 generates proportional and integral adjustment components based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline. Itm2: By determining the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline, the heat load change trend of the exhaust gas pipeline within a certain period of time is determined, and a feedforward compensation component is generated. Itm3 uses a dynamic temperature control command, which combines proportional control, integral control, and feedforward compensation components, to adjust the output power of the heating element in the exhaust gas pipeline and calculate the residual deviation between the updated actual wall temperature and the target constant temperature setpoint.

[0006] In a preferred embodiment, the step of generating a proportional adjustment component and an integral adjustment component based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline includes: By comparing the target constant temperature setpoint in the exhaust gas pipeline with the actual wall temperature at the current moment, the instantaneous temperature difference of the exhaust gas pipeline is obtained. The corresponding proportional adjustment coefficient is determined based on the preset level range in which the instantaneous temperature difference value is positive or negative and its magnitude. The instantaneous temperature difference is adjusted according to the proportional adjustment coefficient to obtain the proportional adjustment component.

[0007] In a preferred embodiment, the step of generating a proportional adjustment component and an integral adjustment component based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline further includes: The deviation between the actual wall temperature value and the target constant temperature set value is continuously collected at multiple sampling times along the time axis; The deviation values ​​are accumulated to obtain the cumulative temperature difference deviation of the deviation values; Determine whether the cumulative temperature difference deviation exceeds the preset cumulative threshold. If it does, generate an integral adjustment component to eliminate steady-state residual deviation based on the cumulative direction and amount of the cumulative temperature difference deviation. If the cumulative threshold is not exceeded, the integral adjustment component is set to zero.

[0008] In a preferred embodiment, determining the heat load change trend of the exhaust gas pipeline over a certain period of time by using the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline includes: The current exhaust gas flow rate at the exhaust gas inlet is continuously collected at a fixed sampling period, and all exhaust gas flow rates are stored in a sliding time window to form a real-time updated flow trajectory sequence. The difference between the starting and ending values ​​of the trajectory in the flow trajectory sequence, the number of times local peaks and valleys appear in the trajectory, and the span duration between each adjacent peak and valley are used as fluctuation pattern characteristics. Based on the characteristics of the fluctuation pattern, the trend of heat load change in the exhaust gas pipeline is determined.

[0009] In a preferred embodiment, determining the heat load variation trend of the exhaust gas pipeline based on the fluctuation morphology characteristics includes: The rising and falling trend of the exhaust gas pipeline is determined by comparing the difference between the starting and ending values ​​of the trajectory in the flow trajectory sequence. Based on the specific judgment results of the rise and fall trend, check the number of times local peaks and valleys appear in the flow trajectory sequence to determine the trend type of the rise and fall trend; The rising and falling trend, along with the trend type, are used as indicators of the heat load change trend in the exhaust gas pipeline.

[0010] In a preferred embodiment, generating the feedforward compensation component includes: The trend indicator and rate of change of heat load are mapped to a preset trend-compensation mapping table to obtain the compensation direction and compensation start-up time advance of the heat load change trend, wherein: When the trend is identified as a continuous upward phase and the rate of change is at the rapid change level, the compensation direction is to reduce the heating power, and the compensation start-up time advance is set to the first advance duration. When the trend is identified as a continuous downward phase and the rate of change is at the rapid change level, the compensation direction is to increase the heating power, and the compensation start-up time advance is set to the first advance duration. When the rate of change is slow, the advance time for compensation activation is set to a second advance time that is less than the first advance time or no advance compensation is performed. Based on the compensation direction and the advance of the compensation start time, feedforward compensation components are generated.

[0011] In a preferred embodiment, the dynamic temperature control command, which is the result of superimposing and fusing the proportional adjustment component, the integral adjustment component, and the feedforward compensation component, includes: The sign directions of the proportional control component, integral control component, and feedforward compensation component are obtained respectively. The sign directions include positive enhancement, negative weakening, or zero. Perform a consistency check on the direction of the sign; When the three directions are exactly the same, the amplitudes of the three are directly added together to generate a dynamic temperature control command for the exhaust gas pipeline. When there are components with opposite directions among the three, the conflict resolution process begins. The amplitudes of two components in opposite directions are compared, the component with the larger amplitude is retained as the dominant component, and the opposing component with the smaller amplitude is discarded. The dominant component is then added to the amplitude of a third component in the same direction to generate a dynamic temperature control command for the exhaust gas pipeline. When positive and negative components exist simultaneously among the three components, and the maximum positive amplitude is equal to the maximum negative amplitude, the dynamic temperature control command is set to the zero correction value to maintain the current output power unchanged.

[0012] In a preferred embodiment, adjusting the output power of the heating element in the exhaust gas pipeline includes: The amplitude range of the dynamic temperature control command is pre-divided into multiple discrete adjustment levels, and each adjustment level corresponds to a fixed output power adjustment step size. Select the corresponding adjustment level based on the range in which the amplitude of the dynamic temperature control command falls; If the amplitude of the dynamic temperature control command fluctuates near the boundary between two adjacent gears in multiple consecutive cycles, the hysteresis comparison mechanism will be activated. The system will only switch to a new adjustment level after the amplitude of the dynamic temperature control command continuously exceeds the boundary threshold for a preset number of consecutive cycles; otherwise, it will maintain the current level. Adjust the step size according to the output power corresponding to the selected adjustment level to change the output power of the heating element.

[0013] In a preferred embodiment, the residual deviation between the calculated updated actual wall temperature value and the target isothermal setpoint includes: The updated actual wall temperature values ​​were obtained at multiple sampling times after the heating element output power was adjusted and the exhaust gas pipeline was running stably. The updated actual wall temperature value at each sampling time is compared with the target constant temperature setpoint to obtain the instantaneous residual difference at each sampling time. Determine if the signs of all instantaneous residual differences are consistent. If they are consistent, determine that the residual deviation is a one-way deviation and output the direction indicator of the one-way deviation. If they are inconsistent, the residual deviation is determined to be an alternating deviation, and the maximum value of the absolute value of the residual difference at each instant is taken as the residual fluctuation amplitude. The direction indicator of the unidirectional deviation or the residual fluctuation amplitude is used as the output result of the residual deviation.

[0014] To address the aforementioned problems, the present invention also provides a constant temperature maintenance system for exhaust gas pipelines based on dynamic temperature control, the system comprising: The integral-proportional calculation module is used to generate proportional adjustment components and integral adjustment components respectively based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature value of the exhaust gas pipeline. The load feedforward compensation module is used to determine the heat load change trend of the exhaust gas pipeline over a certain period of time by using the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline, and generate feedforward compensation components. The integrated temperature control module is used to adjust the output power of the heating element in the exhaust gas pipeline by using a dynamic temperature control command that combines proportional adjustment component, integral adjustment component and feedforward compensation component, and to calculate the residual deviation between the updated actual wall temperature value and the target constant temperature set value.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention determines a proportional adjustment component based on the instantaneous temperature difference between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline. This allows for rapid and synchronous adjustment in response to instantaneous changes in wall temperature. An integral adjustment component is generated based on the cumulative deviation of the temperature difference, continuously correcting the temperature deviation accumulated over multiple cycles in a closed loop. This completely eliminates residual temperature deviations under steady-state operation, ensuring that the pipeline wall temperature remains accurately and stably within the target constant temperature range. This comprehensively improves the instantaneous response capability and steady-state control accuracy of constant temperature control.

[0016] 2. This invention identifies the trend of heat load change by the characteristics of exhaust gas inlet flow and generates a feedforward compensation component. The proportional control component, integral control component and feedforward compensation component are orderly integrated to form a dynamic temperature control command. The output power of the heating element is smoothly adjusted by using graded adjustment levels and a hysteresis comparison mechanism, which effectively avoids frequent jumps and oscillations in power adjustment. At the same time, the updated residual deviation of wall temperature is accurately calculated to adapt to the dynamic fluctuation of heat load in advance, and to continuously and stably maintain the constant temperature of the pipeline, which greatly improves the dynamic adaptability and long-term operational stability of constant temperature maintenance. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart of a method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control, provided in an embodiment of the present invention. Figure 2 A functional block diagram of a waste gas pipeline constant temperature maintenance system based on dynamic temperature regulation is provided in an embodiment of the present invention. The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0019] This application provides a method for maintaining a constant temperature in an exhaust gas pipeline based on dynamic temperature control. The executing entity of this method includes, but is not limited to, at least one of the following electronic devices that can be configured to execute the method provided in this application: a server, a terminal, etc. In other words, the method for maintaining a constant temperature in an exhaust gas pipeline based on dynamic temperature control can be executed by software or hardware installed on a terminal device or a server device. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cloud server cluster. The server can be an independent server or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content delivery networks (CDN), and big data and artificial intelligence platforms.

[0020] Reference Figure 1 The diagram shown is a flowchart illustrating a method for maintaining a constant temperature in an exhaust gas pipeline based on dynamic temperature control, according to an embodiment of the present invention. In this embodiment, the method for maintaining a constant temperature in an exhaust gas pipeline based on dynamic temperature control includes: Itm1 generates proportional and integral adjustment components based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline. In this embodiment of the invention, the step of generating a proportional adjustment component and an integral adjustment component based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline includes: By comparing the target constant temperature setpoint in the exhaust gas pipeline with the actual wall temperature at the current moment, the instantaneous temperature difference of the exhaust gas pipeline is obtained. The corresponding proportional adjustment coefficient is determined based on the preset level range in which the instantaneous temperature difference value is positive or negative and its magnitude. The instantaneous temperature difference is adjusted according to the proportional adjustment coefficient to obtain the proportional adjustment component.

[0021] The method of generating proportional and integral adjustment components based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline, respectively, also includes: The deviation between the actual wall temperature value and the target constant temperature set value is continuously collected at multiple sampling times along the time axis; The deviation values ​​are accumulated to obtain the cumulative temperature difference deviation of the deviation values; Determine whether the cumulative temperature difference deviation exceeds the preset cumulative threshold. If it does, generate an integral adjustment component to eliminate steady-state residual deviation based on the cumulative direction and amount of the cumulative temperature difference deviation. If the cumulative threshold is not exceeded, the integral adjustment component is set to zero.

[0022] The wall temperature of the exhaust gas pipeline is continuously acquired in real time through the wall temperature acquisition element. This value is the actual wall temperature value without correction. The actual wall temperature value is directly compared with the target constant temperature value of the exhaust gas pipeline that is preset and fixed. The difference is calculated by subtracting the actual wall temperature value from the target constant temperature value. The unique difference result is the instantaneous temperature difference value of the exhaust gas pipeline at the current moment.

[0023] Based on the actual application requirements of constant temperature control in the exhaust gas pipeline, the entire range of possible instantaneous temperature difference values ​​is divided into multiple continuously distributed, non-overlapping, and non-intersecting fixed-level intervals according to fixed numerical intervals. Each level interval corresponds to a unique numerical range. First, the positive or negative attribute of the instantaneous temperature difference value is determined to clarify the direction of the temperature deviation. Then, the specific value of the instantaneous temperature difference value is matched one by one with the numerical range of each preset level interval to determine the unique level interval to which the instantaneous temperature difference value belongs. After the matching is completed, the fixed proportional adjustment coefficient pre-bound to that level interval is directly retrieved to complete the determination of the corresponding proportional adjustment coefficient.

[0024] The proportional adjustment coefficient determined in the aforementioned steps is used as the sole basis for adjusting the instantaneous temperature difference. The specific value of the instantaneous temperature difference is scaled proportionally according to the fixed range corresponding to the proportional adjustment coefficient. During the scaling process, the positive and negative attributes of the instantaneous temperature difference remain unchanged. The final value obtained after the scaling process is the proportional adjustment component of the exhaust gas pipeline.

[0025] According to a pre-set and fixed time interval, the actual wall temperature value of the exhaust gas pipeline at each independent sampling moment on the time axis is obtained sequentially. The actual wall temperature value corresponding to each sampling moment is compared with the pre-set target constant temperature value of the exhaust gas pipeline. The result of the calculation is the deviation value at that sampling moment. The deviation value acquisition operation of multiple consecutive sampling moments is continuously completed to ensure that the acquired deviation value covers the entire sampling period.

[0026] All the sampling time deviation values ​​obtained in the previous steps are added one by one in the order of actual collection. The positive or negative attribute of each deviation value is retained during the addition process. The sum of all deviation values ​​is the cumulative temperature deviation of the deviation value.

[0027] The specific value of the cumulative temperature difference deviation is directly compared with the cumulative threshold value that is preset and fixed in the exhaust gas pipeline. When the cumulative temperature difference deviation value is greater than the cumulative threshold value, the positive or negative attribute of the cumulative temperature difference deviation is determined as the accumulation direction. The specific value of the cumulative temperature difference deviation is extracted as the accumulation amount. Based on the accumulation direction and accumulation amount, an integral adjustment component is generated specifically to eliminate steady-state residual deviation.

[0028] When the cumulative temperature difference deviation is less than or equal to the cumulative threshold value, the value of the integral adjustment component is directly set to a fixed zero value, and no integral adjustment effect is generated.

[0029] Itm2: By determining the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline, the heat load change trend of the exhaust gas pipeline within a certain period of time is determined, and a feedforward compensation component is generated. In this embodiment of the invention, determining the heat load change trend of the exhaust gas pipeline over a certain period of time by using the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline includes: The current exhaust gas flow rate at the exhaust gas inlet is continuously collected at a fixed sampling period, and all exhaust gas flow rates are stored in a sliding time window to form a real-time updated flow trajectory sequence. The difference between the starting and ending values ​​of the trajectory in the flow trajectory sequence, the number of times local peaks and valleys appear in the trajectory, and the span duration between each adjacent peak and valley are used as fluctuation pattern characteristics. Based on the characteristics of the fluctuation pattern, the trend of heat load change in the exhaust gas pipeline is determined.

[0030] The determination of the heat load variation trend of the exhaust gas pipeline based on the fluctuation pattern characteristics includes: The rising and falling trend of the exhaust gas pipeline is determined by comparing the difference between the starting and ending values ​​of the trajectory in the flow trajectory sequence. Based on the specific judgment results of the rise and fall trend, check the number of times local peaks and valleys appear in the flow trajectory sequence to determine the trend type of the rise and fall trend; The rising and falling trend, along with the trend type, are used as indicators of the heat load change trend in the exhaust gas pipeline.

[0031] The generation of feedforward compensation components includes: The trend indicator and rate of change of heat load are mapped to a preset trend-compensation mapping table to obtain the compensation direction and compensation start-up time advance of the heat load change trend, wherein: When the trend is identified as a continuous upward phase and the rate of change is at the rapid change level, the compensation direction is to reduce the heating power, and the compensation start-up time advance is set to the first advance duration. When the trend is identified as a continuous downward phase and the rate of change is at the rapid change level, the compensation direction is to increase the heating power, and the compensation start-up time advance is set to the first advance duration. When the rate of change is slow, the advance time for compensation activation is set to a second advance time that is less than the first advance time or no advance compensation is performed. Based on the compensation direction and the advance of the compensation start time, feedforward compensation components are generated.

[0032] According to a preset and fixed sampling period, the real-time exhaust gas flow rate value at the exhaust gas inlet installation location of the exhaust gas pipeline is continuously collected by the exhaust gas flow rate acquisition element. Each time a new exhaust gas flow rate value is collected, the value is stored in a sliding time window with a preset fixed duration. As the sampling sequence progresses, the sliding time window continuously removes old flow rate values ​​that exceed the fixed duration range of the window, while simultaneously incorporating the latest collected flow rate values. All valid flow rate values ​​retained in the window are arranged in the order of actual collection, forming a real-time dynamically updated flow trajectory sequence after the arrangement is completed.

[0033] The flow value at the first position in the flow trajectory sequence is extracted and defined as the trajectory start value. The flow value at the last position is extracted and defined as the trajectory end value. The difference between the trajectory end value and the trajectory start value is calculated to obtain the first-to-last difference. All flow values ​​in the flow trajectory sequence are completely traversed to identify local peak points where the value is greater than the adjacent flow value on the left and right. Local valley points where the value is less than the adjacent flow value on the left and right are identified. The total number of local peak points and local valley points is counted to obtain the frequency of local peaks and valleys. The number of sampling periods between each pair of adjacent local peak points and local valley points is recorded. The number of sampling periods is converted into the corresponding time length to obtain the span duration between each pair of adjacent peaks and valleys. The first-to-last difference, the frequency of local peaks and valleys, and the span duration between each pair of adjacent peaks and valleys are used together as the fluctuation pattern characteristics of the flow trajectory sequence.

[0034] The difference between the beginning and end of the fluctuation pattern, the number of times local peaks and valleys occur, and the span duration between each adjacent peak and valley are used as the core criteria for judging the heat load change. Combined with the pre-set flow fluctuation pattern and heat load change correspondence rules of the exhaust gas pipeline, the three types of fluctuation pattern characteristics are precisely matched with the preset heat load change states in the rules one by one. Based on the matching results, the heat load change trend of the exhaust gas pipeline within the corresponding time range of the sliding time window is finally determined.

[0035] The determined starting and ending values ​​of the trajectory are extracted from the flow trajectory sequence. The difference between the beginning and end values ​​is obtained by subtracting the starting value from the ending value. The difference between the beginning and end values ​​is directly and accurately compared with zero. When the difference between the beginning and end values ​​is greater than zero, the upward trend of the exhaust gas pipeline is determined to be an upward trend. When the difference between the beginning and end values ​​is less than zero, the upward trend of the exhaust gas pipeline is determined to be a downward trend. When the difference between the beginning and end values ​​is equal to zero, the upward trend of the exhaust gas pipeline is determined to be a stable trend.

[0036] Based on the determined rise and fall trend judgment results, the number of local peaks and valleys in the flow trajectory sequence is retrieved and statistically analyzed. The number of local peaks and valleys is then precisely matched with the pre-set thresholds for stable, gradually changing, and rapidly changing trends in the exhaust gas pipeline. When the number of local peaks and valleys is completely consistent with the stable threshold, the trend type of the rise and fall trend is determined to be stable. When the number of local peaks and valleys is completely consistent with the gradually changing threshold, the trend type of the rise and fall trend is determined to be gradually changing. When the number of local peaks and valleys is completely consistent with the rapidly changing threshold, the trend type of the rise and fall trend is determined to be rapidly changing.

[0037] The determined rise and fall trends and their corresponding trend types are directly combined, and the resulting combination is directly used as the heat load change trend of the exhaust gas pipeline.

[0038] Retrieve the trend identifier and rate of change level corresponding to the determined heat load change trend, and accurately match the trend identifier and rate of change level with each configuration item in the pre-set trend-compensation mapping table of the exhaust gas pipeline. After successful matching, directly read the compensation direction and compensation start time advance marked by the corresponding configuration item in the mapping table.

[0039] When the trend indicator of heat load change is determined to be in a continuous upward phase and the rate of change is in the rapid change level, the compensation direction is directly set to reduce the heating power, and the compensation start time advance is fixed to the first advance time preset in the exhaust gas pipeline.

[0040] When the trend indicator of the heat load change trend is a continuous decline stage and the change rate level is a rapid change level, the compensation direction is directly set to increase the heating power, and the compensation start time advance is fixed to the first advance time preset by the exhaust gas pipeline.

[0041] When the rate of change of heat load is determined to be slow, the advance time of compensation is directly fixed to the second advance time of the exhaust gas pipeline, which is less than the first advance time. Alternatively, the advance compensation operation can be canceled and no compensation advance time is set.

[0042] Using the final determined compensation direction and compensation start-up time advance as the core basis for generation, the compensation direction and compensation start-up time advance are integrated according to the pre-set feedforward compensation construction rules of the exhaust gas pipeline, and a complete feedforward compensation component is formed after integration.

[0043] Itm3 uses a dynamic temperature control command, which combines proportional control, integral control, and feedforward compensation components, to adjust the output power of the heating element in the exhaust gas pipeline and calculate the residual deviation between the updated actual wall temperature and the target constant temperature setpoint.

[0044] In this embodiment of the invention, the dynamic temperature control command, which is the result of superimposing and fusing the proportional adjustment component, the integral adjustment component, and the feedforward compensation component, includes: The sign directions of the proportional control component, integral control component, and feedforward compensation component are obtained respectively. The sign directions include positive enhancement, negative weakening, or zero. Perform a consistency check on the direction of the sign; When the three directions are exactly the same, the amplitudes of the three are directly added together to generate a dynamic temperature control command for the exhaust gas pipeline. When there are components with opposite directions among the three, the conflict resolution process begins. The amplitudes of two components in opposite directions are compared, the component with the larger amplitude is retained as the dominant component, and the opposing component with the smaller amplitude is discarded. The dominant component is then added to the amplitude of a third component in the same direction to generate a dynamic temperature control command for the exhaust gas pipeline. When positive and negative components exist simultaneously among the three components, and the maximum positive amplitude is equal to the maximum negative amplitude, the dynamic temperature control command is set to the zero correction value to maintain the current output power unchanged.

[0045] The adjustment of the output power of the heating element in the exhaust gas pipeline includes: The amplitude range of the dynamic temperature control command is pre-divided into multiple discrete adjustment levels, and each adjustment level corresponds to a fixed output power adjustment step size. Select the corresponding adjustment level based on the range in which the amplitude of the dynamic temperature control command falls; If the amplitude of the dynamic temperature control command fluctuates near the boundary between two adjacent gears in multiple consecutive cycles, the hysteresis comparison mechanism will be activated. The system will only switch to a new adjustment level after the amplitude of the dynamic temperature control command continuously exceeds the boundary threshold for a preset number of consecutive cycles; otherwise, it will maintain the current level. Adjust the step size according to the output power corresponding to the selected adjustment level to change the output power of the heating element.

[0046] The residual deviation between the calculated updated actual wall temperature value and the target isothermal setpoint includes: The updated actual wall temperature values ​​were obtained at multiple sampling times after the heating element output power was adjusted and the exhaust gas pipeline was running stably. The updated actual wall temperature value at each sampling time is compared with the target constant temperature setpoint to obtain the instantaneous residual difference at each sampling time. Determine if the signs of all instantaneous residual differences are consistent. If they are consistent, determine that the residual deviation is a one-way deviation and output the direction indicator of the one-way deviation. If they are inconsistent, the residual deviation is determined to be an alternating deviation, and the maximum value of the absolute value of the residual difference at each instant is taken as the residual fluctuation amplitude. The direction indicator of the unidirectional deviation or the residual fluctuation amplitude is used as the output result of the residual deviation.

[0047] The regulation effect attributes of the proportional regulation component, integral regulation component, and feedforward compensation component are read one by one. Based on the heating power control trend reflected by the regulation effect attributes, the sign direction of each component is accurately determined. The sign direction of the proportional regulation component, integral regulation component, and feedforward compensation component is uniquely determined to be one of three states: positive enhancement, negative weakening, or zero. There are no other determination results.

[0048] The sign directions of the proportional adjustment component, the integral adjustment component, and the feedforward compensation component are compared one by one to fully verify whether the sign directions of the three are completely consistent, thus completing the accurate verification of the direction consistency.

[0049] When the signs of the proportional control component, integral control component, and feedforward compensation component are all in the same direction, the amplitudes of the proportional control component, integral control component, and feedforward compensation component are extracted respectively. The three amplitudes are then summed in sequence. The final result of the summation is combined with the unified sign direction of the three components to generate a dynamic temperature control command for the exhaust gas pipeline.

[0050] When the sign directions of the proportional adjustment component, integral adjustment component, and feedforward compensation component simultaneously exhibit two opposite states—positive enhancement and negative weakening—the preset conflict resolution process is automatically initiated and executed to normalize the directional conflicts between the components.

[0051] During the conflict resolution process, the amplitude values ​​of two components with opposite directions are extracted and compared precisely. The component with the larger amplitude value is retained as the dominant component, and the component with the smaller amplitude value is discarded as the opposing component. Then, the amplitude value of the third component with the same sign direction as the dominant component is extracted. The amplitude values ​​of the dominant component and the third component are accumulated. The result of the accumulation calculation is combined with the sign direction corresponding to the dominant component to generate a dynamic temperature control command for the exhaust gas pipeline.

[0052] When the proportional control component, integral control component, and feedforward compensation component simultaneously exhibit both positive enhancement and negative reduction sign directions, and the maximum amplitude of all positive components is exactly equal to the maximum amplitude of all negative components, the dynamic temperature control command of the exhaust gas pipeline is directly set to the zero correction value, and the current output power of the heating element remains unchanged according to the control requirements of the zero correction value.

[0053] Based on the power control range of the exhaust gas pipeline heating element, the entire amplitude range of the dynamic temperature control command is evenly divided into multiple non-overlapping and non-intersecting discrete intervals according to fixed numerical intervals. Each discrete interval corresponds to an independent adjustment level, and a unique and fixed output power adjustment step size is bound to each adjustment level. The output power adjustment step size is a fixed increase or decrease value that the output power of the heating element can execute.

[0054] Read the amplitude value of the currently generated dynamic temperature control command, match the amplitude value with the amplitude intervals corresponding to each pre-divided adjustment level, accurately determine the unique amplitude interval to which the amplitude value belongs, and select the adjustment level corresponding to the interval as the currently selected adjustment level.

[0055] The system continuously monitors the real-time changes of the amplitude value of the dynamic temperature adjustment command within a preset number of sampling periods. When the amplitude value fluctuates back and forth near the boundary value of the amplitude range between two adjacent adjustment levels, the preset hysteresis comparison mechanism is automatically activated, and the system enters a stable adjustment state.

[0056] During the operation of the hysteresis comparison mechanism, it continuously verifies whether the amplitude value of the dynamic temperature adjustment command exceeds the boundary threshold of the adjacent gear. When the amplitude value exceeds the boundary threshold and the state remains unchanged for a preset number of consecutive cycles, the adjustment gear switching operation is performed and the new adjustment gear is changed. When the amplitude value exceeds the boundary threshold but the state does not reach the preset number of consecutive cycles, the currently used adjustment gear remains unchanged.

[0057] Extract the fixed output power adjustment step size bound to the currently selected adjustment level, and adjust the current output power of the exhaust gas pipeline heating element accordingly based on the value and direction of the output power adjustment step size, so as to accurately complete the adjustment of the heating element output power.

[0058] After the heating element completes the output power adjustment, the operating status of the exhaust gas pipeline is continuously monitored. The pipeline wall temperature is collected at multiple consecutive sampling times according to a fixed sampling period. This value is the updated actual wall temperature value after the heating power adjustment.

[0059] The updated actual wall temperature value obtained at each sampling moment is compared with the target constant temperature set value preset in the exhaust gas pipeline. The result of the difference at each independent moment is the instantaneous residual difference corresponding to that sampling moment.

[0060] The sign attribute of the instantaneous residual difference at each sampling time is checked one by one. When the sign attribute of all instantaneous residual differences is exactly the same, the residual deviation is formally determined as a one-way deviation, and the direction identifier corresponding to the unified sign is extracted.

[0061] When the sign attribute of all instantaneous residual differences has different states of positive and negative, the residual deviation is formally determined as alternating deviation. The absolute value of each instantaneous residual difference is calculated in turn, and the result with the largest value among all the calculated absolute values ​​is selected as the residual fluctuation amplitude.

[0062] The direction indicator corresponding to the unidirectional deviation or the residual fluctuation amplitude corresponding to the alternating deviation is used as the final output result of the residual deviation obtained in this calculation process.

[0063] like Figure 2 The diagram shown is a functional block diagram of a waste gas pipeline constant temperature maintenance system based on dynamic temperature regulation, provided in an embodiment of the present invention.

[0064] The dynamic temperature control-based exhaust gas pipeline constant temperature maintenance system M00 described in this invention can be installed in an electronic device. Depending on the functions implemented, the dynamic temperature control-based exhaust gas pipeline constant temperature maintenance system M00 may include an integral-proportional calculation module M01, a load feedforward compensation module M02, and a fusion temperature control module M03. The module described in this invention can also be called a unit, referring to a series of computer program segments that can be executed by the processor of an electronic device and perform a fixed function, stored in the memory of the electronic device.

[0065] In this embodiment, the functions of each module / unit are as follows: The integral-proportional calculation module is used to generate proportional adjustment components and integral adjustment components respectively based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature value of the exhaust gas pipeline. The load feedforward compensation module is used to determine the heat load change trend of the exhaust gas pipeline within a certain period of time by using the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline, and generate feedforward compensation components. The fusion temperature control module is used to adjust the output power of the heating element in the exhaust gas pipeline by using a dynamic temperature control command that combines proportional adjustment component, integral adjustment component and feedforward compensation component, and to calculate the residual deviation between the updated actual wall temperature value and the target constant temperature set value.

[0066] In the several embodiments provided by this invention, it should be understood that the disclosed methods and systems can be implemented in other ways. For example, the system embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and other division methods may be used in actual implementation.

[0067] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0068] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional modules.

[0069] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0070] This application embodiment can acquire and process relevant data based on artificial intelligence technology. Artificial intelligence is the theory, method, technology, and application system that uses digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to obtain optimal results.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control, characterized in that, The method includes: Itm1 generates proportional and integral adjustment components based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline. Itm2: By determining the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline, the heat load change trend of the exhaust gas pipeline within a certain period of time is determined, and a feedforward compensation component is generated. Itm3 uses a dynamic temperature control command, which combines proportional control, integral control, and feedforward compensation components, to adjust the output power of the heating element in the exhaust gas pipeline and calculate the residual deviation between the updated actual wall temperature and the target constant temperature setpoint.

2. The method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control as described in claim 1, characterized in that, The process involves generating proportional and integral adjustment components based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline, including: By comparing the target constant temperature setpoint in the exhaust gas pipeline with the actual wall temperature at the current moment, the instantaneous temperature difference of the exhaust gas pipeline is obtained. The corresponding proportional adjustment coefficient is determined based on the preset level range in which the instantaneous temperature difference value is positive or negative and its magnitude. The instantaneous temperature difference is adjusted according to the proportional adjustment coefficient to obtain the proportional adjustment component.

3. The method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control as described in claim 1, characterized in that, The method of generating proportional and integral adjustment components based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature of the exhaust gas pipeline, respectively, also includes: The deviation between the actual wall temperature value and the target constant temperature set value is continuously collected at multiple sampling times along the time axis; The deviation values ​​are accumulated to obtain the cumulative temperature difference deviation of the deviation values; Determine whether the cumulative temperature difference deviation exceeds the preset cumulative threshold. If it does, generate an integral adjustment component to eliminate steady-state residual deviation based on the cumulative direction and amount of the cumulative temperature difference deviation. If the cumulative threshold is not exceeded, the integral adjustment component is set to zero.

4. The method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control as described in claim 1, characterized in that, The method of determining the heat load change trend of the exhaust gas pipeline over a certain period of time by using the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline includes: The current exhaust gas flow rate at the exhaust gas inlet is continuously collected at a fixed sampling period, and all exhaust gas flow rates are stored in a sliding time window to form a real-time updated flow trajectory sequence. The difference between the starting and ending values ​​of the trajectory in the flow trajectory sequence, the number of times local peaks and valleys appear in the trajectory, and the span duration between each adjacent peak and valley are used as fluctuation pattern characteristics. Based on the characteristics of the fluctuation pattern, the trend of heat load change in the exhaust gas pipeline is determined.

5. The method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control as described in claim 4, characterized in that, The determination of the heat load variation trend of the exhaust gas pipeline based on the fluctuation pattern characteristics includes: The rising and falling trend of the exhaust gas pipeline is determined by comparing the difference between the starting and ending values ​​of the trajectory in the flow trajectory sequence. Based on the specific judgment results of the rise and fall trend, check the number of times local peaks and valleys appear in the flow trajectory sequence to determine the trend type of the rise and fall trend; The rising and falling trend, along with the trend type, are used as indicators of the heat load change trend in the exhaust gas pipeline.

6. The method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control as described in claim 1, characterized in that, The generation of feedforward compensation components includes: The trend identifier and rate of change of heat load are mapped to a preset trend-compensation mapping table to obtain the compensation direction and compensation start-up time advance of the heat load change trend, wherein: When the trend is identified as a continuous upward phase and the rate of change is at the rapid change level, the compensation direction is to reduce the heating power, and the compensation start-up time advance is set to the first advance duration. When the trend is identified as a continuous downward phase and the rate of change is at the rapid change level, the compensation direction is to increase the heating power, and the compensation start-up time advance is set to the first advance duration. When the rate of change is slow, the advance time for compensation activation is set to a second advance time that is less than the first advance time or no advance compensation is performed. Based on the compensation direction and the advance of the compensation start time, feedforward compensation components are generated.

7. The method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control as described in claim 1, characterized in that, The dynamic temperature control command, which is the result of superimposing and fusing the proportional adjustment component, the integral adjustment component, and the feedforward compensation component, includes: The sign directions of the proportional control component, integral control component, and feedforward compensation component are obtained respectively. The sign directions include positive enhancement, negative weakening, or zero. Perform a consistency check on the direction of the sign; When the three directions are exactly the same, the amplitudes of the three are directly added together to generate a dynamic temperature control command for the exhaust gas pipeline. When there are components with opposite directions among the three, the conflict resolution process begins. The amplitudes of two components in opposite directions are compared, the component with the larger amplitude is retained as the dominant component, and the opposing component with the smaller amplitude is discarded. The dominant component is then added to the amplitude of a third component in the same direction to generate a dynamic temperature control command for the exhaust gas pipeline. When positive and negative components exist simultaneously among the three components, and the maximum positive amplitude is equal to the maximum negative amplitude, the dynamic temperature control command is set to the zero correction value to maintain the current output power unchanged.

8. The method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control as described in claim 1, characterized in that, The adjustment of the output power of the heating element in the exhaust gas pipeline includes: The amplitude range of the dynamic temperature control command is pre-divided into multiple discrete adjustment levels, and each adjustment level corresponds to a fixed output power adjustment step size. Select the corresponding adjustment level based on the range in which the amplitude of the dynamic temperature control command falls; If the amplitude of the dynamic temperature control command fluctuates near the boundary between two adjacent gears in multiple consecutive cycles, the hysteresis comparison mechanism will be activated. The system will only switch to a new adjustment level after the amplitude of the dynamic temperature control command continuously exceeds the boundary threshold for a preset number of consecutive cycles; otherwise, it will maintain the current level. Adjust the step size according to the output power corresponding to the selected adjustment level to change the output power of the heating element.

9. The method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control as described in claim 1, characterized in that, The residual deviation between the calculated and updated actual wall temperature value and the target isothermal setpoint includes: The updated actual wall temperature values ​​were obtained at multiple sampling times after the heating element output power was adjusted and the exhaust gas pipeline was running stably. The updated actual wall temperature value at each sampling time is compared with the target constant temperature setpoint to obtain the instantaneous residual difference at each sampling time. Determine if the signs of all instantaneous residual differences are consistent. If they are consistent, determine that the residual deviation is a one-way deviation and output the direction indicator of the one-way deviation. If they are inconsistent, the residual deviation is determined to be an alternating deviation, and the maximum value of the absolute value of the residual difference at each instant is taken as the residual fluctuation amplitude. The direction indicator of the unidirectional deviation or the residual fluctuation amplitude is used as the output result of the residual deviation.

10. A constant temperature maintenance system for exhaust gas pipelines based on dynamic temperature control, characterized in that, The system for implementing the method for maintaining constant temperature in an exhaust gas pipeline based on dynamic temperature control as described in claim 1 includes: The integral-proportional calculation module is used to generate proportional adjustment components and integral adjustment components respectively based on the instantaneous temperature difference and cumulative temperature difference deviation between the target constant temperature setpoint and the actual wall temperature value of the exhaust gas pipeline. The load feedforward compensation module is used to determine the heat load change trend of the exhaust gas pipeline over a certain period of time by using the current exhaust gas flow rate at the exhaust gas inlet in the exhaust gas pipeline, and generate feedforward compensation components. The integrated temperature control module is used to adjust the output power of the heating element in the exhaust gas pipeline by using a dynamic temperature control command that combines proportional adjustment component, integral adjustment component and feedforward compensation component, and to calculate the residual deviation between the updated actual wall temperature value and the target constant temperature set value.

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