Phosphate sintering temperature intelligent control method and system

Abstract

The application discloses a phosphate sintering temperature intelligent control method and system, and belongs to the technical field of temperature control. The method specifically comprises the following steps: collecting sintering parameters in a sintering process of a phosphate blank, generating state quantities of an equivalent core temperature and a hearth temperature gradient of the blank based on the collected sintering parameters, and constructing an equivalent temperature state model of the sintering process; analyzing the equivalent temperature state model, identifying phase change characteristic information of a dehydration and crystal phase conversion process of the phosphate system, and generating a target sintering temperature trajectory corresponding to the phase change characteristic information according to the phase change characteristic information; and intelligently controlling the phosphate sintering process based on the target sintering temperature trajectory. The application can change the sintering control from experience-dependent external temperature adjustment to active perception and accurate guidance based on the internal thermal state and phase change behavior of the material, thereby helping to improve the stability and consistency of the sintering process and improve the structural uniformity and performance stability of the phosphate product.

Description

Technical Field

[0001] This invention belongs to the field of temperature control technology, specifically a method and system for intelligent control of phosphate sintering temperature. Background Technology

[0002] Phosphate materials, as a material system with unique chemical bonding structures and thermal transformation characteristics, are widely used in the preparation of refractories, functional ceramics, structural bonding materials, and special inorganic composite materials. During sintering, they typically undergo multi-stage phase transformation processes, including structural dehydration, binder phase formation, and crystal phase rearrangement. Different stages correspond to different temperature ranges and thermal history requirements, and the rationality of sintering temperature control directly affects the formation of the microstructure and the stability of the final properties of the product. However, due to the strong temperature sensitivity and thermal process coupling of the phosphate system, its sintering behavior is difficult to effectively control through simple fixed temperature profiles.

[0003] Existing phosphate sintering processes mostly rely on empirically set heating curves and limited temperature measurement points for process control. They depend mainly on the furnace ambient temperature rather than the actual thermal state of the billet. Under complex working conditions, it is difficult to reflect the internal temperature distribution and temperature gradient changes of the billet. This often leads to problems such as local overheating, abrupt transitions in the dehydration stage, or insufficient crystal phase transformation, resulting in uneven internal structure, large performance fluctuations, and inconsistent product quality. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes an intelligent control method and system for phosphate sintering temperature, which can sense the internal thermal state of the green body and identify phase transformation characteristics, and achieve intelligent control of phosphate sintering temperature with adaptive adjustment.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for intelligent control of phosphate sintering temperature includes:

[0007] Sintering parameters are collected during the sintering process of phosphate green bodies, including furnace temperature parameters, atmosphere parameters, green body loading parameters, and furnace pressure parameters.

[0008] Based on the collected sintering parameters, the state variables of the equivalent core temperature of the green body and the temperature gradient of the furnace are generated, and the equivalent temperature state model of the sintering process is constructed.

[0009] The equivalent temperature state model is analyzed to identify the phase transformation characteristics of the phosphate system dehydration and crystal phase transformation process, and a target sintering temperature trajectory is generated based on the phase transformation characteristics. The target sintering temperature trajectory uses a nonlinear adjustment method to limit the internal temperature gradient of the green body within the phase transformation range.

[0010] Based on the target sintering temperature trajectory, the phosphate sintering process is intelligently controlled.

[0011] Specifically, the process of generating state variables for the equivalent core temperature of the green body and the temperature gradient of the furnace based on the collected sintering parameters, and constructing an equivalent temperature state model for the sintering process, includes:

[0012] The collected sintering parameters are divided into two dimensions: time domain and spatial domain, to form a set of domain parameters;

[0013] Based on the aforementioned set of domain parameters, the sintering operation records for different time periods are sorted and a memory sequence is generated. The memory sequence is used to characterize the cumulative impact of historical operations on the current thermal state during the sintering process.

[0014] Using the memory sequence as input, and combining the geometric features of the billet and the loading method information, a mapping relationship is established between the external parameters of the furnace and the implicit temperature state inside the billet.

[0015] Based on the mapping relationship, multiple potential temperature state quantities inside the billet are comprehensively derived to determine the equivalent core temperature of the thermal center region inside the billet.

[0016] The equivalent core temperature is correlated with the furnace temperature parameters to generate a temperature gradient state variable, which, together with the equivalent core temperature, constitutes the equivalent temperature state model of the sintering process.

[0017] Specifically, based on the mapping relationship, multiple potential temperature state quantities inside the billet are comprehensively derived to determine the equivalent core temperature of the thermal center region inside the billet, including:

[0018] Based on the mapping relationship, the hidden temperature points in different internal regions of the billet are inferred one by one to form a potential temperature state candidate set covering the central region and the boundary transition region of the billet.

[0019] For each potential temperature state in the candidate temperature state set, the potential state is filtered according to the spatial connectivity of the heat transfer path inside the billet, and potential state points that are not sufficiently related to the thermal center region are excluded to obtain the target potential temperature state set.

[0020] The target potential temperature state set is time-series aligned and stage-wise reorganized so that its transformation sequence in the sintering thermal history matches the formation process of the internal thermal center of the billet, forming a time-consistent state group.

[0021] Based on the time-consistent state group, the equivalent core temperature representing the temperature of the thermal center region inside the billet is determined by comprehensively deriving multiple potential temperature states.

[0022] Specifically, the equivalent core temperature is correlated with the furnace temperature parameters to generate a temperature gradient state variable, which, together with the equivalent core temperature, constitutes an equivalent temperature state model for the sintering process, including:

[0023] The furnace temperature parameters are sorted into layers according to the distribution of heating zones, airflow path and billet arrangement, forming a layered set of temperature parameters.

[0024] Based on the equivalent core temperature, the temperature parameter hierarchical set is correlated layer by layer to establish the correspondence between the equivalent core temperature and the temperature of different areas of the furnace.

[0025] Based on the aforementioned correspondence, the temperature parameters of each layer of the furnace are reorganized according to the order of temperature elevation and spatial continuity to construct a temperature sequence state.

[0026] The temperature sequence state is processed together with the equivalent core temperature to generate a temperature gradient state quantity, which, together with the equivalent core temperature, forms the equivalent temperature state model of the sintering process.

[0027] Specifically, the equivalent temperature state model is analyzed to identify phase transformation characteristics of the phosphate system's dehydration and crystal phase transformation processes, and a corresponding target sintering temperature trajectory is generated based on these phase transformation characteristics, including:

[0028] The equivalent core temperature and temperature gradient state quantities in the equivalent temperature state model are analyzed in time segments, and the stages are divided according to the sintering thermal process to form a set of temperature state segments.

[0029] Based on the temperature state segment set, the inflection points of temperature change, the sudden change trend of temperature gradient, and the characteristics of the stage-stable interval are extracted to generate a phase transition candidate characteristic set.

[0030] The set of candidate phase transition features is classified and processed according to their order of appearance and duration in the thermal process. The features related to structural dehydration are distinguished from those related to crystal phase transformation, thus forming an initial set of phase transition features.

[0031] The initial set of phase transition features is integrated and processed. Through comprehensive analysis of the continuity, repeatability and persistence of features in adjacent stages, the phase transition feature windows corresponding to the dehydration process and the crystal phase transformation process are determined.

[0032] Based on the phase transformation feature window, a temperature trajectory structure is constructed in the order of heating, holding and cooling stages. The temperature change mode and stage boundary position of each stage are set to generate a target sintering temperature trajectory corresponding to the phase transformation feature information.

[0033] Specifically, the initial set of phase transition characteristics is integrated, and through comprehensive analysis of the continuity, repeatability, and persistence of characteristics in adjacent stages, phase transition characteristic windows corresponding to the dehydration process and the crystal phase transformation process are determined, including:

[0034] The feature characteristics from adjacent thermal processes in the initial set of phase transition features are compared one by one to determine their consistency at the stage boundary, thus forming a candidate set of stage connection.

[0035] Screen the feature signs that appear with a frequency higher than a preset value or have a continuous distribution in the candidate set of stage transitions, identify duplicate signs, and construct a target sign set with duplicate attribute identifiers.

[0036] The target symptom set is organized by time structure. Based on the existence span and duration of each symptom in the thermal process, it is divided and combined into time segments to form a staged symptom combination.

[0037] Based on the aforementioned staged characteristic combinations, the characteristic combinations related to the structural dehydration process and the characteristic combinations related to the crystal phase transformation process are separated to determine the phase transformation characteristic windows corresponding to the dehydration process and the crystal phase transformation process.

[0038] Specifically, based on the phase transformation feature window, a temperature trajectory structure is constructed in the order of heating, holding, and cooling stages. The temperature change mode and stage boundary position of each stage are set to generate a target sintering temperature trajectory corresponding to the phase transformation feature information, including:

[0039] Each phase transition characteristic window is assigned to the heating stage, the holding stage, and the cooling stage according to its time position in the thermal history, forming a phase transition window stage assignment set.

[0040] Based on the set of phase change window stages, multiple temperature anchor points and time anchor points corresponding to the edge of the phase change window are set in the heating stage, the heat preservation stage and the cooling stage, and the anchor points are combined to form a stage boundary anchor point sequence.

[0041] For each stage boundary anchor point sequence, a nonlinear heating method is selected in the heating stage, a segmented holding or gradual change method is selected in the heat preservation stage, and a segmented cooling method is selected in the cooling stage. The method is then associated with the phase change characteristic window within that stage to form a combination of temperature change methods.

[0042] Following the order of heating, holding, and cooling stages, the temperature change patterns of each stage are combined with the corresponding stage boundary anchor point sequence and continuously assembled along the time axis to generate the target sintering temperature trajectory corresponding to the phase transformation feature window in the entire thermal history.

[0043] Specifically, based on the target sintering temperature trajectory, intelligent control of the phosphate sintering process is performed, including:

[0044] The target sintering temperature trajectory is divided into stages of heating, holding and cooling. For each stage, a corresponding trajectory reference value and stage switching condition are set to form a target trajectory reference set.

[0045] During the phosphate sintering process, the real-time equivalent core temperature and temperature gradient state are obtained and matched segment by segment with the target trajectory reference set to generate temperature state matching results.

[0046] Based on the temperature state matching results, deviation judgments are made for the heating, heat preservation and cooling stages respectively, and the corresponding adjustment trigger categories are determined according to the deviation judgment results;

[0047] Based on the aforementioned adjustment trigger category, the joint adjustment amount is determined according to the stage attributes;

[0048] After executing the joint adjustment, the real-time equivalent core temperature and temperature gradient state quantity are deviated again to complete the intelligent control of the phosphate sintering process.

[0049] Specifically, based on the aforementioned adjustment trigger category, the joint adjustment amount is determined according to the stage attributes, including:

[0050] The different adjustment trigger categories generated in the heating stage, heat preservation stage and cooling stage are collected and processed, and each adjustment trigger category is mapped to a stage set with the same stage attribute to form a trigger category stage mapping relationship.

[0051] For each set of stages in the trigger category stage mapping relationship, a priority sequence of stage control elements is formed based on the change pattern of the temperature trajectory within that stage.

[0052] According to the priority sequence of the stage control elements, in each stage set, two or more means are selected from a variety of adjustment means for combination, and the combination is matched one-to-one with the corresponding adjustment trigger category to form a set of adjustment means combination within the stage.

[0053] Based on the set of adjustment methods within the current stage, the adjustment trigger categories in the current stage are matched accordingly. By jointly setting the adjustment amplitude and adjustment order of the selected adjustment methods in the current stage, a joint adjustment amount is generated.

[0054] A phosphate sintering temperature intelligent control system is used to implement the aforementioned phosphate sintering temperature intelligent control method, comprising: a parameter acquisition module, a model construction module, a trajectory generation module, and an intelligent control module;

[0055] The parameter acquisition module is used to acquire sintering parameters during the sintering process of phosphate green bodies;

[0056] The model building module generates state variables of the equivalent core temperature of the billet and the temperature gradient of the furnace based on the collected sintering parameters, and constructs an equivalent temperature state model of the sintering process.

[0057] The trajectory generation module is used to analyze the equivalent temperature state model, identify the phase transformation characteristics of the phosphate system dehydration and crystal phase transformation process, and generate the corresponding target sintering temperature trajectory based on the phase transformation characteristics.

[0058] The intelligent control module is used to intelligently control the phosphate sintering process based on the target sintering temperature trajectory.

[0059] Compared with the prior art, the beneficial effects of the present invention are:

[0060] This invention proposes an intelligent control method and system for phosphate sintering temperature. By constructing an equivalent temperature state model based on the equivalent core temperature and furnace temperature gradient, the dehydration and phase transformation characteristics during phosphate sintering are identified. Based on this, a target sintering temperature trajectory corresponding to the phase transformation window is generated, which serves as the basis for intelligent control of the phosphate sintering process. This enables sintering control to shift from experience-based external temperature regulation to proactive sensing and precise guidance based on the internal thermal state and phase transformation behavior of the material. This helps improve the stability and consistency of the sintering process, reduce the impact of abnormal operating conditions, improve the structural uniformity and performance stability of phosphate products, and enhance the overall preparation quality and production reliability. Furthermore, by combining a staged closed-loop collaborative control strategy and an adaptive adjustment mechanism, the entire process of heating, holding, and cooling is dynamically controlled and jointly regulated, thereby achieving intelligent temperature management of the entire phosphate sintering process. Attached Figure Description

[0061] Figure 1 A flowchart of an intelligent control method for phosphate sintering temperature provided by the present invention;

[0062] Figure 2 A schematic diagram illustrating the construction of the equivalent temperature state model provided by this invention;

[0063] Figure 3 A schematic diagram of the target sintering temperature trajectory provided by the present invention;

[0064] Figure 4 This invention provides an architecture diagram of an intelligent control system for phosphate sintering temperature. Detailed Implementation

[0065] The present application will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application. These all fall within the protection scope of the present application.

[0066] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0067] It should be noted that, unless there is a conflict, the various features in the embodiments of this application can be combined with each other, and all are within the protection scope of this application. Furthermore, although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described can be performed in a different order than the module division in the device or the order in the flowchart.

[0068] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application.

[0069] Example 1

[0070] See Figure 1 The present invention provides an embodiment of a method for intelligent control of phosphate sintering temperature, comprising the following specific steps:

[0071] Step S1: Collect sintering parameters during the sintering process of phosphate green bodies, including furnace temperature parameters, atmosphere parameters, green body loading parameters, and furnace pressure parameters.

[0072] In this embodiment, by setting temperature acquisition points distributed at different heights and flow field channel positions within the sintering furnace, and combining online acquisition of atmosphere parameters (including oxygen content, nitrogen partial pressure, humidity, CO2 concentration, etc.) at the furnace inlet and outlet paths with synchronous monitoring of billet loading density, stacking method, and furnace pressure changes, key process quantities of phosphate billets during sintering are collected collaboratively. The principle is that by treating the furnace ambient temperature as an external thermal excitation source, using atmosphere parameters and furnace pressure as constraint boundary conditions for the heat and mass transfer process, and using billet loading parameters as important structural variables affecting the heat transfer path and thermal hysteresis behavior, the above-mentioned multi-source process quantities are normalized and time-series calibrated with a unified time reference, so that they together constitute data information reflecting the completeness of the sintering thermal history.

[0073] Step S2: Based on the collected sintering parameters, generate the state variables of the equivalent core temperature of the billet and the temperature gradient of the furnace, and construct the equivalent temperature state model of the sintering process.

[0074] like Figure 2 As shown, the specific steps of step S2 are as follows:

[0075] Step S201: Divide the collected sintering parameters into two dimensions, time domain and spatial domain, to form a set of domain parameters.

[0076] In this embodiment, the collected furnace temperature parameters, atmosphere parameters, billet loading parameters, and furnace pressure parameters are processed in a two-dimensional division of time and space. The principle is that the sintering process is regarded as a coupled process that continues to advance over time and undergoes differentiated evolution along the furnace space. First, taking the sintering process as the time reference, the original parameters are divided into time segments according to the heating stage, phase change sensitive stage, heat holding stage, and cooling stage, so that each type of parameter corresponds to a specific thermal history stage. Then, taking the distribution of the heating zone inside the furnace, the main airflow channel path, and the location of the billet loading area as the spatial reference, the parameters of different measurement points and different action areas are spatially aggregated and hierarchically organized. By establishing a stage-based continuous relationship on the time axis and a regional pointing relationship in the spatial domain, the original scattered process data is transformed into a set of domain parameters with stage attributes and spatial affiliation.

[0077] Step S202: Based on the set of domain parameters, sort the sintering operation records of different time periods and generate a memory sequence. The memory sequence is used to characterize the cumulative impact of historical operations on the current thermal state during the sintering process.

[0078] In this embodiment, based on the constructed set of domain parameters, the sintering operation records at different time stages are sequentially rearranged. The principle is that the sintering thermal process is not a single instantaneous state, but a time-cumulative effect process formed by the superposition of continuous operations. Therefore, it is necessary to use time progression as the dominant axis to time-calibrate and reconstruct the sequence of temperature adjustment commands, atmosphere adjustment behaviors, furnace pressure changes, and loading-related operation events in each stage, so that each operation behavior can be traced and located at a clear time position. After completing the time ordering, the operation records of each stage are serially superimposed in a continuous manner to construct an overall thermal history operation chain covering the heating stage, phase change sensitive stage, heat preservation stage, and cooling stage, and further form a memory sequence reflecting the sequential relationship of historical operation behaviors. It should be noted that this memory sequence does not directly correspond to a certain instantaneous temperature value, but is a kind of time-structured information used to express the cumulative contribution and path dependence of past operations on the current thermal state. In this way, the thermal state at any time is no longer regarded as an instantaneously measured result, but is defined as a result state that has evolved gradually from previous operations.

[0079] Step S203: Using the memory sequence as input, and combining the geometric features of the billet and the loading method information, establish a mapping relationship between the external parameters of the furnace and the implicit temperature state inside the billet.

[0080] In this embodiment, the memory sequence obtained in step S202 is used as the time-structured input. Combined with the geometric dimensions, volume morphology, specific surface area characteristics, and loading information such as stacking layer thickness, stacking method, and spacing between adjacent billets, a correspondence between the apparent process parameters of the furnace and the implicit temperature state inside the billet is constructed. The principle is that the furnace temperature parameters, atmosphere parameters, and furnace pressure parameters are regarded as externally observable driving forces, and the billet geometry and loading conditions are regarded as structural constraints affecting the heat conduction path, thermal hysteresis behavior, and heat storage capacity. By jointly modeling the two with the time-continuous memory sequence, a traceable logical coupling chain is formed between the thermal history sequence, spatial heat transfer conditions, and external process excitations. This allows the influence of furnace environment changes on different positions inside the billet to have a derivation trajectory as time progresses. Thus, a mapping relationship is established to infer the internal temperature state of the billet that cannot be directly measured from the apparent parameters of the furnace. In the above way, the potential temperature state at multiple positions inside the billet is transformed into an implicit state quantity expression form with a correlation derivation basis.

[0081] It should be noted that the mapping relationship between the external parameters of the furnace and the implicit temperature state inside the billet is established through a combination of data and physical constraints. Specifically, a training sample set is first constructed based on historical sintering process data. The input features include furnace temperature parameters, atmosphere parameters, furnace pressure parameters, and the loading structure parameters at the corresponding time. The output labels are the temperature data of key locations inside the billet obtained through embedded temperature measurement or offline calibration. Subsequently, a regression model is used to fit and model the relationship between the input features and the output temperature. The regression model can be a multiple linear regression model, a support vector regression model, or a feedforward neural network model. During the model training process, constraints based on the heat conduction mechanism are introduced to correct the physical rationality of the model output results and avoid abnormal predictions that violate the laws of heat conduction. Finally, the trained mapping model realizes the function of deriving the implicit temperature state inside the billet from the external parameters of the furnace, so that the mapping relationship has a clear data source, modeling method, and output path.

[0082] Step S204: Based on the mapping relationship, a comprehensive derivation is performed on multiple potential temperature state quantities inside the billet to determine the equivalent core temperature of the thermal center region inside the billet.

[0083] The specific steps of step S204 are as follows:

[0084] Step S2041: Based on the mapping relationship, the hidden temperature points in different internal regions of the billet are inferred one by one to form a potential temperature state candidate set covering the central region and the boundary transition region of the billet.

[0085] In this embodiment, based on the established mapping relationship between the external parameters of the furnace and the implicit temperature state inside the billet, the regions with temperature response differences inside the billet are partitioned and inferred. The principle is that the billet as a whole is regarded as a multi-layered thermal behavior structure consisting of a central thermal hysteresis region, a transitional slowly changing region, and a near-surface rapid response region. On this basis, the time-cumulative excitation reflected by the memory sequence is used as the driving quantity, and the heat conduction path formed by the billet geometry and loading method is used as the constraint condition. The implicit temperature points of each corresponding internal region in the mapping relationship are inferred one by one, so that each region obtains an internal potential temperature expression that matches its location attributes and heat transfer characteristics under a unified logical framework. Through this method of unfolding by region and inferring point by point by location, a candidate set of potential temperature states covering the central region to the boundary transition region of the billet is formed. The temperature states of different regions inside the billet no longer exist in a single estimated form, but are clearly expressed in the form of a candidate set with spatial distribution meaning and location differentiation ability.

[0086] Step S2042: For each potential temperature state in the candidate temperature state set, filter according to the spatial connectivity of the heat transfer path inside the billet, eliminate potential state points that are not sufficiently related to the thermal center region, and obtain the target potential temperature state set.

[0087] In this embodiment, the potential temperature state candidate set obtained in step S2041 is subjected to a spatial logic constraint screening process. The principle is that the thermal center region inside the billet is regarded as the result region formed by the combined influence of multiple heat transfer paths. First, based on the heat conduction direction, heat diffusion connection path and thermal coupling channel formed between regions defined by the billet geometry and loading method, a spatial connectivity mapping is established for the position of each potential temperature state in the candidate set. On this basis, taking the thermal center region as the reference starting point, it is judged whether each potential state point is in a region with a continuous heat transfer coupling link with the thermal center. Potential state points that only have a weak correlation with the near-surface rapid thermal response region or only have a short-term thermal coupling with a local isolated region and are difficult to form a stable heat transfer path are eliminated. Only temperature state points that form a continuous correlation with the thermal center region through spatial connectivity links are retained, thereby obtaining a target potential temperature state set with clear central correlation.

[0088] Step S2043: Perform time series alignment and phased reorganization on the target potential temperature state set so that the transformation sequence in the sintering thermal history matches the formation process of the internal thermal center of the billet, forming a time-consistent state group.

[0089] In this embodiment, the obtained set of target potential temperature states undergoes temporal sequence processing and phased structural reorganization. The principle is that the formation of thermal centers does not occur simultaneously in each internal region, but rather is a dynamic process of accumulation from the external heat input to the interior through different heat transfer paths, progressing gradually with the sintering thermal process. Therefore, it is necessary to first align each target potential temperature state according to its corresponding time position based on the operation time markers reflected in the memory sequence, so that it obtains a clear arrangement order on a unified time axis. Subsequently, based on the heating stage, phase change sensitive stage, and thermal stability stage as segmentation criteria, the target potential temperature states in the same or adjacent thermal stages are reorganized in stages. States with temporal continuity and evolutionary inheritance relationships are combined and merged, and the transition relationships between different stages are sequentially connected, thereby establishing a one-to-one correspondence between the trajectory of internal temperature state changes and the physical process of the gradual formation and evolution of thermal centers. Through this temporal sequence alignment and phased reconstruction processing, the set of temperature states that originally only had spatial center correlation significance is transformed into a time-consistent state group with clear temporal evolution significance.

[0090] Step S2044: Based on the time consistency state group, the equivalent core temperature representing the temperature of the internal thermal center region of the billet is determined by comprehensively deriving multiple potential temperature states.

[0091] In this embodiment, based on the obtained time-consistent state group, multiple potential temperature states belonging to different spatial locations and at different time stages are comprehensively derived. The principle is that the thermal center region is understood as a common result region formed by the continuous superposition of multiple heat transfer paths in the time dimension. Therefore, instead of simply selecting the temperature of a single region, the time-consistent state group is used as the input. First, based on the temporal inheritance relationship of each potential temperature state at different stages, an evolutionary chain reflecting the gradual inward accumulation of heat is constructed. Then, the potential temperature states of different nodes in each evolutionary chain are used as... The constituent elements are analyzed by joint reasoning regarding their spatial location attributes, the degree of correlation with heat transfer paths, and the degree of continuous contribution during the temporal progression. This gives higher representational weight to the temperature states that actually participate in the formation of the thermal center during the comprehensive derivation process, while temperature states that only have marginal response significance or short-term existence significance are gradually weakened. After completing the above comprehensive derivation, a representative temperature result reflecting the overall thermal energy accumulation level in the thermal center region inside the billet is obtained, and this result is determined as the equivalent core temperature. Thus, the internal thermal center state, which cannot be directly measured, is clearly expressed in the form of an equivalent temperature for control and analysis.

[0092] Step S205: Correlate the equivalent core temperature with the furnace temperature parameters to generate a temperature gradient state variable, which together with the equivalent core temperature constitutes the equivalent temperature state model of the sintering process.

[0093] The specific steps of step S205 are as follows:

[0094] Step S2051: The furnace temperature parameters are sorted into layers according to the distribution of heating zones, airflow path and billet arrangement to form a layered set of temperature parameters.

[0095] In this embodiment, the temperature parameters acquired within the furnace are not processed as a single whole. Instead, based on the furnace structure and thermal field organization, the temperature acquisition points within the furnace are first divided into physical zones according to the heating area, giving each heating zone an independent block attribute in terms of temperature representation. Subsequently, using the airflow paths of the main airflow channel, recirculation zone, and local disturbance zone within the furnace as references, the temperature parameters within the same block are further organized at a second level, forming airflow characteristic association groups based on temperature data with similar airflow characteristics. Next, constrained by loading method information such as billet stacking height, horizontal arrangement, and billet spacing, the aforementioned airflow characteristic association groups are further correlated by position and hierarchically merged, so that the temperature data not only possess heating area attributes and airflow attributes but also have spatial meaning directly related to the billet arrangement. Through the above multi-layered logical decomposition and reconstruction process, the furnace temperature data, originally collected at different points and recorded at different times and being independent, are transformed into a hierarchical set of temperature parameters with structural hierarchical semantics and spatial orientation.

[0096] Step S2052: Based on the equivalent core temperature, perform layer-by-layer correspondence association on the temperature parameter hierarchical set to establish the correspondence between the equivalent core temperature and the temperature of different regions of the furnace.

[0097] In this embodiment, the equivalent core temperature determined in step S2044 is used as the benchmark reference for the internal thermal state of the billet. The temperature parameter set obtained in step S2051 is processed layer by layer for correlation. The principle is as follows: First, the equivalent core temperature is considered as the temperature formed after the overall thermal field of the furnace acts on the inside of the billet and undergoes multi-stage heat transfer attenuation. Therefore, the heating zone stratification is used as the first correlation level, establishing a correspondence between the temperature of each heating zone and the equivalent core temperature, thus creating a one-to-one correspondence between the external heat input intensity and the internal thermal center state of different heating zones. Subsequently, the airflow path stratification is used as the second correlation level, based on the heat exchange efficiency and heat distribution uniformity of different airflow channels. To mitigate the impact of temperature variations, a differentiated response relationship is established between temperature data under different airflow paths within the same heating zone and the equivalent core temperature, ensuring that the external temperature distribution reflects the bias trend of the internal temperature field. Furthermore, the arrangement of billets is layered into a third correlation level. Based on the thermal coupling characteristics formed by the billet loading position, stacking density, and adjacent relationships, the mapping between the temperature of each region and the equivalent core temperature is refined, ensuring that the correlation not only reflects regional temperature differences but also the differences in heat transfer paths caused by the loading structure. Through the above progressive method, a multi-level correspondence mapping is established, ultimately forming a hierarchical and positionally oriented correspondence between the equivalent core temperature and the temperatures of different regions of the furnace.

[0098] Step S2053: Based on the correspondence, the temperature parameters of each layer of the furnace are reorganized according to the order of temperature high and low and spatial continuity to construct a temperature sequence state.

[0099] In this embodiment, based on the correspondence between the equivalent core temperature and the temperatures of different regions of the furnace established in step S2052, the temperature parameters of each layer of the furnace are no longer simply arranged linearly by measurement point location or section number. Instead, they are reorganized based on the core organizational principle of temperature elevation and spatial continuity. The principle is that, firstly, according to the elevation relationship of each layer's temperature parameters relative to the equivalent core temperature, the temperature parameters of different heating zones, different airflow paths, and different loading zones are initially sorted, so that the temperature values ​​have a directional meaning of gradually transitioning from the external strong excitation zone to the internal thermal response zone; subsequently, based on the above temperature elevation sorting, By introducing the spatial connectivity of the furnace structure and the continuity of airflow, temperature points that are only numerically similar but lack continuous heat transfer logic in their spatial location are eliminated or repositioned to ensure that adjacent temperature points in the same temperature sequence have both asymptotic numerical relationships and spatial heat transfer connectivity. After completing the above two-dimensional reconstruction, the sorted and spatially constrained temperature parameters are arranged according to a continuous path, thereby forming a temperature sequence state that reflects the gradual transfer from the high-temperature region of the furnace to the region near the billet and finally points to the equivalent core temperature. This transforms the furnace temperature distribution from discrete point data into a temperature sequence expression with directional meaning and structural coherence.

[0100] Step S2054: Combine the temperature sequence state with the equivalent core temperature to generate a temperature gradient state quantity, and combine it with the equivalent core temperature to form an equivalent temperature state model for the sintering process.

[0101] In this embodiment, the temperature sequence state obtained in step S2053 and the equivalent core temperature determined in step S2044 are jointly processed. The principle is as follows: First, the temperature points in the temperature sequence state that change progressively from the outside to the inside are taken as a continuous temperature chain that transmits the external heat field of the furnace to the inside of the billet. This temperature chain serves as the basic carrier for describing the external temperature distribution structure and its directionality. Then, the equivalent core temperature is taken as the endpoint reference quantity corresponding to this temperature chain inside the billet. The temperature difference relationship and spatial connection relationship of each temperature point in the temperature sequence relative to the equivalent core temperature are comprehensively analyzed. Under the premise of maintaining the consistency of the temperature gradient direction and the continuity of heat transfer logic, the temperature difference structure expression that reflects the temperature field change law from the outside of the furnace to the inside of the billet is extracted as a whole. Based on this, a temperature gradient state quantity with clear directional attributes and hierarchical structure meaning is generated. On this basis, the temperature gradient state quantity and the equivalent core temperature are structurally combined so that the internal thermal center state and the external temperature field change relationship are included in the same thermal state expression framework, thereby forming an equivalent temperature state model of the sintering process with integrity, hierarchy and logical correlation.

[0102] Step S3: Analyze the equivalent temperature state model, identify the phase transformation characteristics of the phosphate system dehydration and crystal phase transformation process, and generate the corresponding target sintering temperature trajectory based on the phase transformation characteristics. The target sintering temperature trajectory uses a nonlinear adjustment method to limit the internal temperature gradient of the green body within the phase transformation range.

[0103] The specific steps of step S3 are as follows:

[0104] Step S301: Perform time segmentation analysis on the equivalent core temperature and temperature gradient state quantities in the equivalent temperature state model, divide them into stages according to the sintering thermal process, and form a set of temperature state segments.

[0105] In this embodiment, a time-dimensional analytical mechanism is introduced into the equivalent core temperature and temperature gradient state quantities in the equivalent temperature state model. The principle is to view the sintering process as a thermal history process that evolves segment by segment along time. First, as... Figure 3As shown, taking the sintering process as the main time axis, and based on typical process segments such as the heating start-up stage, the dehydration and structural adjustment sensitive stage, the crystal phase transformation dominant stage, the thermal stability maintenance stage, and the subsequent cooling stage, the time series data of the equivalent core temperature and temperature gradient state quantities are segmented and their boundaries are defined, so that each time period corresponds to a type of thermal process unit with relatively consistent thermal behavior characteristics. Subsequently, after completing the time boundary division, the equivalent core temperature change trajectory and the corresponding temperature gradient evolution trajectory within the same time stage are grouped and aggregated, so that the internal thermal center state and the external temperature field change state form a coupled expression relationship within the same time segment. Through the above time segmentation analysis and stage organization reconstruction, the originally continuous and complex equivalent temperature state sequence is transformed into a set of temperature state segments with clear stage attributes and time orientation significance.

[0106] Step S302: Based on the temperature state segment set, extract the inflection points of temperature change, the sudden change trend of temperature gradient, and the characteristics of the staged stable interval to generate a phase transition candidate characteristic set.

[0107] In this embodiment, the temperature state segment set obtained in step S301 is used as the analysis object. Feature extraction processing is performed on the equivalent core temperature change trajectory and temperature gradient state evolution trajectory within each time stage. The principle is that the rate and direction of change of the equivalent core temperature are used as sensitive indicators of the material's internal heat absorption and structural adjustment behavior, and the continuity and abrupt change tendency of the temperature gradient over time are used as the basis for determining the matching state between the external thermal field driving force and the internal thermal response. Specifically, using each time segment as a boundary, the differences in the continuous change trend of the temperature curve within the segment are identified, and the inflection point feature of temperature change from slow change to rapid change or from rising to slowing down is extracted. Simultaneously, the temperature... The gradient change sequence over time is scanned to identify gradient abrupt changes or directional shifts within short time intervals. Furthermore, segments with small temperature changes over longer time intervals and stable coupling between the equivalent core temperature and temperature gradient are calibrated to extract stage-specific stable interval characteristics. Through parallel extraction and unified organization of these multiple types of characteristics, a set of candidate phase transition characteristics, including temperature inflection points, gradient abrupt changes, and stable plateaus, is ultimately formed. It should be noted that the specific forms of nonlinearity, such as exponential heating, piecewise polynomial regulation, and logarithmic gradual change, are used, and the temperature change inflection point is set by those skilled in the art based on the actual situation.

[0108] Specifically, for temperature inflection points, the rate of change of the first derivative of the equivalent core temperature over time is calculated. When the derivative changes sign within a continuous time window and the magnitude of the change exceeds a preset threshold, that location is identified as a temperature inflection point. For abrupt temperature gradient changes, the temperature gradient state variable is differentially calculated. When the gradient change rate between adjacent time points exceeds a set threshold proportion, it is identified as a gradient abrupt change. For a periodically stable interval, the fluctuation range of the equivalent core temperature within a preset time window is judged to be lower than a stability threshold, while the temperature gradient change remains within a defined range. If these conditions are met, it is marked as a stable interval. By introducing the above-mentioned judgment rules based on derivatives, differences, and fluctuation ranges, the phase transition characteristic identification process is transformed from qualitative description to quantitative judgment.

[0109] Step S303: Classify the set of candidate phase transition features. Based on the order of appearance and duration in the thermal process, distinguish between features related to structural dehydration and features related to crystal phase transformation to form an initial set of phase transition features.

[0110] In this embodiment, the set of phase transition candidate signs obtained in step S302 is classified with process semantic constraints. The principle is that structural dehydration and crystal phase transformation during phosphate sintering typically occur at different stages of the thermal history, manifesting as dehydration behavior signs that appear earlier, have a relatively limited duration, but are highly sensitive to temperature gradients, and crystal phase transformation signs that appear later, have a longer duration, and are accompanied by gradual stabilization of the thermal state. Therefore, firstly, the candidate signs are sorted according to their order of appearance in the thermal history, based on the time series, so that different signs obtain clear temporal location attributes; subsequently, the duration is further classified... Based on the continuity of temperature change amplitude and temperature gradient coupling characteristics, signs in the early stage with rapid response and stage-specific abrupt changes are identified as signs related to the dehydration process. Signs in the middle and later stages with relatively continuous gradient changes and stage-stable plateau characteristics are identified as signs related to the crystal phase transformation process. Signs with temporal overlap or behavioral intersection are assigned and corrected by combining their evolution trends before and after the stages. After the above comprehensive classification based on time sequence, continuous structure and gradient behavior, an initial set of phase transformation characteristics corresponding to the dehydration process and the crystal phase transformation process are formed respectively.

[0111] Step S304: Integrate the initial set of phase transition features, and determine the phase transition feature windows corresponding to the dehydration process and the crystal phase transformation process through comprehensive analysis of the continuity, repeatability and persistence of the characteristics of adjacent stages.

[0112] The specific steps of step S304 are as follows:

[0113] Step S3041: Compare the feature characteristics from adjacent thermal processes in the initial set of phase transition features one by one, determine their consistency of connection at the stage boundary, and form a candidate set of stage connection.

[0114] In this embodiment, based on the initial set of phase transformation features obtained in step S303, feature characteristics from adjacent thermal process stages are compared one by one. The principle is that dehydration and crystal phase evolution during phosphate sintering are often not instantaneously separated at the stage boundary, but are manifested in a gradual transition between adjacent stages. Therefore, it is necessary to identify the continuous correlation between the feature characteristics of the two stages in the physical process by comprehensively judging the proximity of their occurrence time, the continuity of temperature change direction, and the inheritance of temperature gradient evolution trend. Specifically, firstly, taking the stage boundary time as a reference, the feature at the end of the stage is matched one by one with the feature at the beginning of the next stage to determine whether they constitute a continuously advancing thermal process chain in terms of time position. Subsequently, based on the consistency of the temperature evolution trend and gradient change direction of the two, objects that do not have logical continuity or show abrupt breakage characteristics are eliminated, and only feature combinations that have stage transition logic and process evolution continuity are retained. Through the above screening and corresponding confirmation, a stage connection candidate set reflecting the consistency of connection between different thermal process stages is finally formed.

[0115] Step S3042: Screen the feature signs that appear with a frequency higher than a preset value or have a continuous distribution in the candidate set of stage transitions, confirm the duplicate signs, and construct a target sign set with duplicate attribute identifiers.

[0116] In this embodiment, the candidate set of stage transitions obtained in step S3041 is processed for repetitive feature identification and target feature extraction. The principle is that the feature features that truly have phase transition significance usually do not appear randomly, but rather exhibit a regular pattern of repetition or continuous distribution at different stage transition positions or different time segments. Therefore, the candidate set of stage transitions is first used as the analysis object. According to the number of times the feature features appear at the boundaries of different stages and the span of continuous distribution on the time axis, each feature is statistically scanned and its distribution is identified. Specifically, features that repeatedly appear at the transition positions of multiple stages and maintain similarity in adjacent time segments are identified. The signs of changing trends are identified as high-confidence signs indicating a stable process. At the same time, signs that appear only occasionally in a single stage or are isolated are weakened or eliminated to remove false features introduced by occasional disturbances or local anomalies. After the above screening is completed, signs that meet the preset frequency or continuous distribution criteria are marked as repeated signs and given a repeated attribute label to distinguish them from general candidate signs in subsequent analysis. The target sign set constructed in this way not only retains feature information that is highly consistent with the stage connection relationship, but also has stable phase transition semantics confirmed by both repeatability and continuity.

[0117] Step S3043: Organize the target symptom set into a time structure. Based on the existence span and duration of each symptom in the thermal process, divide and combine them into time segments to form a phased symptom combination.

[0118] In this embodiment, based on the target feature set obtained in step S3042 and marked with repeating attribute identifiers, the distribution structure of each feature feature in the time dimension is systematically organized. The principle is that features truly indicating phase transition are not instantaneous isolated events, but exist in a continuous or phased manner within a certain thermal history interval. Therefore, firstly, based on the start position, end position, and coverage span of each feature on the thermal history time axis, the target features are time-localized and interval-labeled, so that each feature has a clear time boundary attribute. Subsequently, based on features with overlapping or continuous time segments, the distribution structure of each feature is systematically organized. It divides and combines segments according to time coverage, so that signs that are in the same or adjacent thermal process stages and have a time inheritance relationship or stable continuity relationship are combined into sign aggregation units with stage semantics. Furthermore, in the combination process, signs that are discontinuous but still under the same phase change trend are supplemented and associated through the evolution trend of the preceding and following stages, so that the combined units not only reflect the continuous existence of the interval, but also reflect the evolution logic of the thermal process. Through the above time structure sorting and segment reconstruction, a stage sign combination that reflects the continuity, integrity and stage belonging characteristics of phase change behavior in different thermal process stages is finally formed.

[0119] Step S3044: Based on the aforementioned staged characteristic combination, the characteristic combination related to the structural dehydration process and the characteristic combination related to the crystal phase transformation process are separated respectively, and the phase transformation characteristic window corresponding to the dehydration process and the crystal phase transformation process is determined.

[0120] In this embodiment, based on the established staged symptom combinations, the process attributes corresponding to different staged symptom combinations are further segmented and analyzed. The principle is that although structural dehydration and crystal phase transformation during phosphate sintering partially overlap in time, they have essential differences in stage duration, temperature dependence, and gradient evolution trend. Therefore, the time coverage interval and stage position of the staged symptom combinations are used as the initial classification criteria. Symptom combinations in the early to middle stages of the thermal process, exhibiting a relatively limited duration and accompanied by sensitive temperature gradient changes, are initially classified into the dehydration-related category. Symptom combinations in the middle to later stages of the thermal process, with a relatively longer duration and a more gradual temperature change and a gradually stabilizing gradient, are classified into the dehydration-related category. The identified symptom combinations are initially categorized into crystal phase transformation-related categories. Subsequently, based on the evolutionary consistency among the symptom combinations, the stage connection relationships, and whether adjacent stages exhibit a stable and continuous trend as they progress, the aforementioned preliminary classification results are corrected for consistency. Combination units with occasional disturbances or those that only appear briefly in local stages are eliminated, while characteristic segments reflecting continuous phase transformation processes are retained. Through the above-mentioned segmentation and correction processes, the phase transformation characteristic windows of the dehydration process and the crystal phase transformation process, which have clear time ranges, stage attributes, and process-oriented significance, are finally determined, so that the phase transformation intervals that are truly representative of the process are clearly defined in both the time dimension and the process semantic dimension.

[0121] Step S305: Based on the phase transformation feature window, construct a temperature trajectory structure in the order of heating, holding and cooling stages, set the temperature change mode and stage boundary position for each stage, and generate a target sintering temperature trajectory corresponding to the phase transformation feature information.

[0122] The specific steps of step S305 are as follows:

[0123] Step S3051: Assign each phase change characteristic window to the heating stage, holding stage, and cooling stage according to its time position in the thermal process, forming a phase change window stage assignment set.

[0124] In this embodiment, the phase transformation characteristic windows of the dehydration process and the crystal phase transformation process are first identified. Their start and end times in the overall sintering thermal process are used as the core basis for stage determination. Each phase transformation window is time-positioned and stage-mapped on a unified time axis. The principle is that the sintering process typically progresses in a heating stage—holding stage—cooling stage. Different stages correspond to different thermal driving methods and structural evolution conditions. Therefore, it is necessary to compare the time coverage intervals of each phase transformation characteristic window with the stage boundary relationships, identifying those whose time positions are in the rapid temperature increase range and are clearly related to the heat input increase process. Phase transition windows are assigned to the heating stage; phase transition windows whose covering temperature remains relatively stable within a high range and exhibit continuous structural evolution are assigned to the heat preservation stage; and phase transition windows in the range where the thermal state gradually declines and exhibits a process of structural stabilization are assigned to the cooling stage. After completing the above assignments, phase transition windows near stage boundaries that exhibit stage-crossing characteristics are assigned by combining their internal symptom evolution trends and logical connections with adjacent stages to avoid ambiguity or overlap in stage determination. In this way, a set of phase transition window stage assignments is formed that establishes a clear correspondence between each phase transition characteristic window and a specific process stage.

[0125] Step S3052: Based on the set of phase change window stages, set multiple temperature anchor points and time anchor points corresponding to the edge of the phase change window in the heating stage, the heat preservation stage and the cooling stage respectively, and combine the anchor points to form a stage boundary anchor point sequence.

[0126] In this embodiment, based on the established set of phase change window stages, anchor point systems with clear boundary orientations are constructed for the heating, holding, and cooling stages. The principle is that the starting and ending edges of the phase change window are considered key alignment and controllable positions of the temperature trajectory within the stage. Multiple representative temperature and time reference points are set around these edges within each stage. Temperature anchor points are used to limit the temperature advancement height and turning points within the stage, while time anchor points are used to limit the stage's advancement rhythm and dwell intervals. Specifically, a set of temperature and time anchor points is set around the entry point and pre-entry position of the phase change window during the heating stage; maintenance anchor points are set around the main stable range of the phase change window during the holding stage; and fallback anchor points are set around the exit point of the phase change window and the subsequent structural stable range during the cooling stage. The anchor points within each stage are combined and arranged in chronological order to form a sequence of stage boundary anchor points with continuous constraint meaning within the same stage. Through this process, the phase change window no longer exists merely as an interval but is transformed into a stage boundary control framework composed of multiple temperature-time anchor points.

[0127] Step S3053: For each stage boundary anchor point sequence, select a nonlinear heating method in the heating stage, a segmented holding or gradual change method in the heat preservation stage, and a segmented cooling method in the cooling stage. Then associate the method with the phase change characteristic window in that stage to form a combination of temperature change methods.

[0128] In this embodiment, a structural constraint framework designed with the boundary anchor point sequence of each stage as the temperature trajectory is used. Temperature change patterns matching the phase transition behavior characteristics are selected for the heating, holding, and cooling stages. The principle is to prevent the temperature evolution over time from following a simple linear or fixed gradient progression pattern, instead employing a change path with differentiated rhythmic control characteristics in different stages. Specifically, in the heating stage, the temperature and time anchor points near the phase transition window in the anchor point sequence are used as control benchmarks. By setting a nonlinear heating mode between adjacent anchor points, the temperature approaches the phase transition window in multiple acceleration / deceleration combinations, such as a slow initial phase followed by a rapid one, or a rapid initial phase followed by a slow one, thus reserving necessary thermal response adjustment space for the upcoming dehydration or structural adjustment. In the holding stage, the temperature changes according to the phase transition behavior characteristics. Taking the anchor points of the main phase transition window as the core, the temperature is finely adjusted in several small increments around the characteristic range during the phase transition period by configuring segmented holding or slowly changing temperature methods between different anchor points, in order to adapt to the phased advancement requirements of the phase transition process. In the cooling phase, the anchor points corresponding to the exit edge of the phase transition window and the subsequent structurally stable section are used as references. By configuring multi-segment cooling methods, the cooling process adopts rapid decline in some intervals and slow transition in others, so as to guide the thermal state to move away from the phase transition sensitive range smoothly. Finally, the nonlinear heating method, segmented holding or slow changing method, and segmented cooling method selected in each stage are associated one by one with the phase transition characteristic window corresponding to their respective stages, forming a combination of temperature change methods for different phase transition sections.

[0129] It should be noted that the nonlinear heating method is implemented through a preset function model. Specifically, during the heating stage, the stage boundary anchor points are used as constraints, and an exponential function or piecewise polynomial function is used to fit the temperature change between adjacent anchor points. The function parameters are determined according to the target temperature span and time span, so that the temperature change rate exhibits gradual or accelerated characteristics in different segments. During the heat preservation stage, a piecewise constant function or a low-slope linear function is set to achieve stable temperature maintenance or slow adjustment. During the cooling stage, a piecewise exponential decay function or a piecewise linear function is used to achieve a gradual temperature drop. Through the above-mentioned nonlinear adjustment method based on the function model, the temperature trajectory has a clear mathematical expression in different stages.

[0130] Step S3054: According to the order of heating, holding and cooling stages, combine the temperature change mode of each stage with the corresponding stage boundary anchor point sequence and continuously assemble them along the time axis to generate the target sintering temperature trajectory corresponding to the phase transformation feature window in the whole thermal history.

[0131] In this embodiment, the target sintering temperature trajectory is constructed as a whole based on the determined temperature change patterns and corresponding stage boundary anchor point sequences of the three stages of heating, holding, and cooling. The principle is to treat the temperature evolution over time within each stage as a series of sub-trajectory segments with boundary constraints and internal change logic, and to perform continuous splicing and transition processing on the same time axis. Specifically, starting with the heating stage, the temperature change patterns within the heating stage are expanded between adjacent temperature and time anchor points to generate a heating sub-trajectory from room temperature to the area before and after the phase change window inlet. The endpoint of this sub-trajectory is then aligned with the starting anchor point in the holding stage anchor point sequence in both time and temperature, ensuring a seamless transition between heating and holding on both the time axis and temperature values. Subsequently, the segmented temperature holding or gradual temperature change patterns within the holding stage are used... Based on the formula, a mid-segment sub-trajectory covering the dehydration or crystal phase transformation dominant region is constructed under the constraint of its corresponding anchor point sequence. The end of this mid-segment sub-trajectory is then continuously connected to the starting anchor point in the cooling stage anchor point sequence, so that the thermal history naturally enters the cooling structure stage after completing the main phase transformation process. Then, in the cooling stage, a multi-segment cooling method is used to unfold between each cooling anchor point, constructing a cooling sub-trajectory from the phase transformation window exit region to the final structural stability region. By sequentially assembling the above three stage sub-trajectories on the time axis and continuously correcting them at the boundary anchor points, the overall temperature trajectory forms a continuous curve from heating in the entire thermal history, crossing the phase transformation window, and then turning to cooling stability. In the segment where each phase transformation characteristic window is located, it presents a temperature change rhythm that matches its characteristics, thereby generating a target sintering temperature trajectory corresponding to the phase transformation characteristic window.

[0132] Figure 3 A schematic diagram of the target sintering temperature trajectory generated based on the method of this invention is shown to illustrate the temperature variation over time and the distribution of stage boundary anchor points in the overall sintering thermal process; for example... Figure 3 As shown, the horizontal axis represents time (min) and the vertical axis represents furnace temperature (°C). The overall temperature trajectory consists of a continuous curve and is divided into three functional sections according to the process logic: heating stage, holding stage, and cooling stage.

[0133] During the heating phase, the temperature trajectory gradually increases from a lower temperature range and enters the medium-high temperature range non-linearly. At least one stage boundary anchor point is set during this phase to limit the pace of the heating process and the temperature boundary before entering the key thermal processes, ensuring that the temperature increase process matches the thermal requirements of the dehydration and initial crystal phase evolution stages. After entering the holding phase, the temperature trajectory tends to level off within the target high temperature range, and a stage boundary anchor point is set during this phase to limit the temperature range and duration of the stable high temperature platform, allowing the material to complete the main crystal phase transformation and structural reconstruction processes within this temperature range. In the subsequent cooling phase, the temperature trajectory slowly or gradually decreases from the high temperature range to a lower temperature range, while cooling stage anchor points are set to constrain the cooling rate and the cooling termination position, avoiding adverse structural effects caused by excessive or insufficient cooling.

[0134] By constructing the temperature trajectory in segments and setting the stage boundary anchor points, the target sintering temperature trajectory not only has continuity and integrity, but also has clear stage attributes and boundary constraints, thereby ensuring the rationality and stability of the thermal history organization of the phosphate sintering process.

[0135] Step S4: Based on the target sintering temperature trajectory, perform intelligent control of the phosphate sintering process.

[0136] The specific steps of step S4 are as follows:

[0137] Step S401: Divide the target sintering temperature trajectory into stages of heating, holding and cooling, and set corresponding trajectory reference values ​​and stage switching conditions for each stage to form a target trajectory reference set.

[0138] In this embodiment, the established target sintering temperature trajectory is used as the overall control benchmark. First, it is divided into three functional thermal history segments according to the sintering process logic: heating stage, holding stage, and cooling stage. The start and end boundary positions of each stage are determined within a unified time axis and temperature axis framework. The principle is to transform the overall temperature trajectory from a continuous curve into a segmented control object with stage attributes, so that each stage can perform target matching and dynamic adjustment within an independent logic unit. Specifically, after the stage division is completed, the temperature trajectory shape within each stage is analyzed, and trajectory reference quantities describing the target temperature path of the stage are extracted, including the stage target temperature range, temperature change trend parameters within the stage, and reference values ​​representing key inflection point characteristics of the stage, which are used as a reference for subsequent real-time control. Meanwhile, by combining the functional positioning and phase transition window distribution of each stage in the thermal process, stage switching conditions are set respectively, so that stage switching no longer simply depends on the progress of time, but is also constrained by multiple factors such as the equivalent core temperature state, the evolution trend of temperature gradient, and the degree of completion of stage target trajectory. In this way, a target trajectory reference set with clear stage objectives and reliable switching logic is formed under the overall continuity framework of temperature trajectory.

[0139] It should be noted that the stage switching conditions are determined through a multi-condition joint judgment method. Specifically, when switching from the heating stage to the heat preservation stage, the equivalent core temperature must reach the lower limit of the target temperature range, the temperature gradient change must be stable, and the duration must reach the minimum maintenance time. When switching from the heat preservation stage to the cooling stage, the phase change characteristic window must be fully covered, the temperature change rate must be lower than the set threshold, and the stage maintenance time must meet the preset requirements. For abnormal switching across stages, the results of the deviation judgment are corrected to prevent premature or delayed switching.

[0140] Step S402: During the phosphate sintering process, the real-time equivalent core temperature and temperature gradient state quantity are obtained and matched segment by segment with the target trajectory reference set to generate temperature state matching results.

[0141] In this embodiment, during the actual sintering process of the phosphate preform, the equivalent core temperature and temperature gradient state variables derived in real time based on the equivalent temperature state model are continuously acquired. The target trajectory reference set established in step S401 is used as the comparison object, and a stage-by-stage matching analysis is performed. The principle is that the real-time sintering thermal state is considered a dynamically evolving quantity, while the target trajectory reference set is considered an ideal thermal history template with stage structure and target constraint significance. First, based on the current sintering process stage, the real-time equivalent core temperature and temperature gradient state variables are limited to the corresponding stage range for matching, considering the degree of temperature numerical similarity, consistency of change trends, and alignment with the stage. The system comprehensively compares the real-time state with the target trajectory of each stage, taking into account dimensions such as the relative relationship of key inflection points, to form a temperature state deviation description for that stage. Subsequently, as time progresses and stage switching conditions are gradually met, the real-time state is automatically switched to the reference value of the next stage target trajectory for matching when the stage switch is completed. This achieves a dynamic comparison mechanism that combines continuous matching within a stage with smooth transition between stages. Through the above segment-by-segment matching and continuous verification process, the real-time equivalent core temperature and temperature gradient state are clearly expressed within the target trajectory framework, and finally, the temperature state matching result reflects the degree of difference and deviation type between the real-time state and the ideal trajectory of each stage.

[0142] Step S403: Based on the temperature state matching results, deviation judgment is performed on the heating, heat preservation and cooling stages respectively, and the corresponding adjustment trigger category is determined according to the deviation judgment results.

[0143] In this embodiment, the temperature state matching result obtained in step S402 is used as the judgment basis to perform deviation judgment and adjustment trigger category determination processing for the heating stage, holding stage and cooling stage respectively. The principle is that the sensitivity, allowable range and adjustment strategies to temperature trajectory deviation are significantly different in different stages of the sintering process. Therefore, it is necessary to implement differentiated deviation identification logic at the stage level. Specifically, in the heating stage, whether the equivalent core temperature increase rate and temperature gradient change trend conform to the target trajectory advancement rhythm is used as the main judgment criterion. When there is a lag in heating, excessively rapid advancement or gradient deviation from the target direction, it is judged as a deviation in the heating stage. In the holding stage, the focus is on whether the equivalent core temperature is maintained within the target stable range and whether the temperature gradient is kept within a reasonable fluctuation range. If the temperature deviates from the stable plateau or the gradient fluctuation disrupts the stage balance relationship, it is identified as a deviation in the holding stage. In the cooling stage, whether the cooling rate and gradient fall rhythm are consistent with the target trajectory is used as the judgment basis. If there is insufficient cooling, excessive cooling or abnormal gradient fallback, it is identified as a deviation in the cooling stage. After identifying deviations at each stage, the deviations are then categorized into different adjustment trigger categories, such as deviations within the trajectory, deviations at stage boundaries, or deviations across stages, based on their location, direction, and severity. This forms adjustment trigger categories with stage attributes and deviation semantics.

[0144] Step S404: Based on the adjustment trigger category, determine the joint adjustment amount according to the stage attribute.

[0145] The specific steps of step S404 are as follows:

[0146] Step S4041: Collect and process the different adjustment trigger categories generated in the heating stage, the heat preservation stage and the cooling stage, and map each adjustment trigger category to a stage set with the same stage attributes to form a trigger category stage mapping relationship.

[0147] In this embodiment, the different types of adjustment trigger categories identified in step S403 within the heating stage, holding stage, and cooling stage are used as basic data objects. These are then collected and mapped based on stage attributes. The principle is that although deviations generated in different stages may have similar characteristics in form, their control significance and adjustment strategies differ due to differences in their thermal history position, phase change process coordination requirements, and temperature trajectory control objectives. Therefore, systematic grouping processing at the stage dimension is necessary. Specifically, based on the source stage label of each adjustment trigger category in the temperature state matching result, categories belonging to the heating process are grouped... Trigger categories generated during the heating phase are uniformly merged into the heating phase set, trigger categories generated during the heat preservation phase are merged into the heat preservation phase set, and trigger categories generated during the cooling phase are merged into the cooling phase set. Subsequently, based on the merging, the trigger categories within each phase are structurally organized, so that deviations within the trajectory, deviations from phase boundaries, and deviations across phases within the same phase obtain clear phase affiliation and logical demarcation. Through the above phase merging and classification mapping, each adjustment trigger category corresponds to a phase set with the same phase attributes under a unified logical framework, thereby forming a trigger category phase mapping relationship with a clear phase pointing relationship.

[0148] Step S4042: For each set of stages in the trigger category stage mapping relationship, a priority sequence of stage control elements is formed based on the change law of the temperature trajectory itself within that stage.

[0149] In this embodiment, based on the trigger category stage mapping relationship formed in step S4041, a priority sequence of control elements adapted to the temperature trajectory change law of each stage set is constructed. The principle is that the temperature trajectories of different stages have significant differences in terms of advancement mode, response rhythm, and sensitivity to control means. Therefore, it is necessary to prioritize the available control elements under stage semantic constraints. Specifically, in the heating stage, based on the characteristics that the temperature trajectory aims to gradually increase and is highly sensitive to changes in external heat input, heating power-related adjustment elements are prioritized at the top of the sequence. Secondly, the effect of atmosphere parameters on heat transfer efficiency and heat absorption behavior is considered. Then, auxiliary adjustment elements related to loading are introduced as needed. In the heat preservation stage, the primary goal is to maintain temperature stability and make minor adjustments. Atmosphere regulation and local thermal field equilibrium control are given higher weight, while heating power changes are used as a secondary means to avoid introducing excessive disturbances. In the cooling stage, the dominant logic is orderly decline and gradient reconstruction. Cooling rhythm control is achieved primarily through power withdrawal and adjustments to atmosphere heat exchange conditions, with auxiliary corrections made when necessary using loading influencing factors. Through the priority sequences formed based on the temperature trajectory's own variation patterns in different stages, the adjustment trigger categories in each stage set are invoked according to a stage-specific priority order when determining subsequent adjustment strategies, thus forming a stage-specific control element priority sequence with a foundation for stage-differentiated control.

[0150] Step S4043: According to the priority sequence of the stage control elements, in each stage set, select two or more means from multiple adjustment means to combine, and match the combination with the corresponding adjustment trigger category to form a set of adjustment means combination within the stage.

[0151] In this embodiment, based on the established priority sequence of stage control elements, adjustment strategies and combinations of methods are constructed for different adjustment trigger categories included in each stage set. The principle is that different trigger categories are often difficult to effectively correct using a single control method. It is necessary to use the stage priority sequence as a constraint framework, selecting two or more synergistic adjustment methods from a variety of feasible adjustment methods in priority order for combination configuration. Specifically, within the heating stage set, prioritizing the order of power adjustment—atmosphere adjustment—loading influence correction, two or more methods are selected from heating power distribution adjustment, regional heating ratio correction, atmosphere flow and composition adjustment, and loading-related compensation adjustment for combination to adapt to the correction requirements of different heating deviation trigger categories. Within the heat preservation stage set… Based on the priority sequence within the aforementioned stages, the core approach typically involves fine-tuning of atmosphere parameters and minor correction of local power. Depending on the situation, thermal field balancing techniques are then combined to address different types of stability deviations and plateau deviation trigger categories. Within the cooling stage set, power pullback control, heat exchange atmosphere adjustment, and stage transition buffer adjustment are combined and matched in different ways according to the cooling rhythm control requirements to address different trigger categories such as insufficient cooling, excessively rapid cooling, and abnormal gradient fall. Subsequently, within each stage, a one-to-one correspondence is established between the different combinations of adjustment methods and specific trigger categories, ensuring that each trigger category has a clear, fixed adjustment combination scheme with stage attribute constraints. This forms a set of intra-stage adjustment method combinations covering different stages of heating, heat preservation, and cooling, with targeted configuration logic.

[0152] Step S4044: Based on the set of adjustment means combinations within the stage, match the corresponding adjustment trigger categories in the current stage, and generate a joint adjustment amount by jointly setting the adjustment amplitude and adjustment order of the selected adjustment means in the stage.

[0153] In this embodiment, based on the set of adjustment means combinations within the current stage determined in step S4043, specific adjustment trigger categories within the current sintering stage are matched accordingly. The principle is that the trigger category is considered an abstract expression of the temperature trajectory deviation nature and correction requirements, while the set of adjustment means combinations within the current stage is considered a control resource pool that satisfies these correction requirements. By searching within the current stage set for adjustment means combinations that establish a one-to-one correspondence with the trigger category, a multi-means coordinated adjustment scheme that can be used for correction in this stage is locked. Subsequently, after determining the adjustment means combination, it is not executed directly with a fixed ratio or a single amplitude, but rather combined with the deviation direction and deviation corresponding to the trigger category. The degree of separation and its relationship with the target trajectory of each stage are used to jointly set the magnitude, sequence, and duration of action of each adjustment method during the execution process. This enables power adjustment, atmosphere adjustment, and other auxiliary adjustment methods to form a control structure with synergy and hierarchical order in terms of time axis and execution intensity. Through the above joint setting, a joint adjustment quantity is generated in the current stage that includes the superposition effect of multiple adjustment methods and clarifies the logic of the sequential action and magnitude distribution of each method. This allows subsequent control execution links to complete a coordinated adjustment process according to the joint adjustment quantity, thereby providing a structured and stage-specific comprehensive control input for the sintering process to return to the target temperature trajectory.

[0154] It should be noted that the joint adjustment amount is generated through a weighted combination of multiple control variables. Specifically, firstly, the set of control variables participating in the adjustment is determined according to the current adjustment trigger category. These control variables include the heating power adjustment amount, the atmosphere flow rate adjustment amount, and the furnace pressure adjustment amount. Subsequently, according to the priority sequence of stage control elements, corresponding weight coefficients are assigned to each control variable, and the basic adjustment range is calculated based on the current temperature deviation. On this basis, the comprehensive adjustment command is obtained by weighting and superimposing the adjustment range of each control variable with its weight coefficient. At the same time, to avoid oscillations or overshoots during the adjustment process, upper limit constraints and rate of change limits are set for the adjustment range, and the adjustment of each control variable is implemented step by step according to the preset execution order.

[0155] Step S405: After executing the joint adjustment, the deviation of the real-time equivalent core temperature and temperature gradient state quantity is judged again to complete the intelligent control of the phosphate sintering process.

[0156] In this embodiment, after the joint adjustment has been implemented during the sintering process and the heating power distribution, furnace atmosphere conditions, and related control quantities have been executed, the sintering process is not directly processed by simply executing and ending. Instead, the equivalent temperature state model is used as the core to re-acquire and update the real-time equivalent core temperature and temperature gradient state quantities. The principle is that the thermal field change after joint adjustment is regarded as a new external excitation condition. By matching and discriminating the real-time thermal state after adjustment with the target trajectory reference set, it is determined whether there is still deviation within the trajectory, deviation at the stage boundary, or cross-trajectory in the current stage. In the event of a stage deviation, if the deviation has been eliminated or returned to within the allowable range, the current control state is maintained and the thermal process continues. If a deviation still exists or evolves into a new type of deviation, the process returns to the deviation diagnosis and adjustment triggering process, sequentially triggering new adjustment decisions and joint control settings to achieve continuous monitoring and dynamic correction of the sintering process. Through this closed-loop logic of adjustment execution, state feedback, deviation re-judgment, and strategy re-decision, the phosphate sintering process remains in a controlled evolution state throughout the entire thermal process, thus constituting an intelligent control operation mechanism with continuous judgment capability, stage adaptive capability, and dynamic correction capability.

[0157] Example 2

[0158] See Figure 4 Another embodiment of the present invention provides: a phosphate sintering temperature intelligent control system, used to implement the phosphate sintering temperature intelligent control method described in Embodiment 1, comprising: a parameter acquisition module, a model construction module, a trajectory generation module and an intelligent control module;

[0159] The parameter acquisition module is used to acquire sintering parameters during the sintering process of phosphate green bodies;

[0160] The model building module generates state variables of the equivalent core temperature of the billet and the temperature gradient of the furnace based on the collected sintering parameters, and constructs an equivalent temperature state model of the sintering process.

[0161] The trajectory generation module is used to analyze the equivalent temperature state model, identify the phase transformation characteristics of the phosphate system dehydration and crystal phase transformation process, and generate the corresponding target sintering temperature trajectory based on the phase transformation characteristics.

[0162] The intelligent control module is used to intelligently control the phosphate sintering process based on the target sintering temperature trajectory.

[0163] The specific functions of each module described above are explained in the relevant content of the intelligent control method for phosphate sintering temperature described in Example 1, and will not be repeated here.

[0164] In addition, the parts of the technical solutions provided in the embodiments of this application that are consistent with the implementation principles of the corresponding technical solutions in the prior art have not been described in detail, so as to avoid excessive elaboration.

[0165] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for intelligent control of phosphate sintering temperature, characterized in that, include: Sintering parameters are collected during the sintering process of phosphate green bodies, including furnace temperature parameters, atmosphere parameters, green body loading parameters, and furnace pressure parameters. Based on the collected sintering parameters, the state variables of the equivalent core temperature of the green body and the temperature gradient of the furnace are generated, and the equivalent temperature state model of the sintering process is constructed. The equivalent temperature state model is analyzed to identify the phase transformation characteristics of the phosphate system dehydration and crystal phase transformation process, and a target sintering temperature trajectory is generated based on the phase transformation characteristics. The target sintering temperature trajectory uses a nonlinear adjustment method to limit the internal temperature gradient of the green body within the phase transformation range. Based on the target sintering temperature trajectory, the phosphate sintering process is intelligently controlled.

2. The intelligent control method for phosphate sintering temperature as described in claim 1, characterized in that, Based on the collected sintering parameters, the equivalent core temperature of the green body and the temperature gradient of the furnace are generated as state variables, and an equivalent temperature state model of the sintering process is constructed, including: The collected sintering parameters are divided into two dimensions: time domain and spatial domain, to form a set of domain parameters; Based on the aforementioned set of domain parameters, the sintering operation records for different time periods are sorted and a memory sequence is generated. The memory sequence is used to characterize the cumulative impact of historical operations on the current thermal state during the sintering process. Using the memory sequence as input, and combining the geometric features of the billet and the loading method information, a mapping relationship is established between the external parameters of the furnace and the implicit temperature state inside the billet. Based on the mapping relationship, multiple potential temperature state quantities inside the billet are comprehensively derived to determine the equivalent core temperature of the thermal center region inside the billet. The equivalent core temperature is correlated with the furnace temperature parameters to generate a temperature gradient state variable, which, together with the equivalent core temperature, constitutes the equivalent temperature state model of the sintering process.

3. The intelligent control method for phosphate sintering temperature as described in claim 2, characterized in that, Based on the mapping relationship, multiple potential temperature state quantities inside the billet are comprehensively derived to determine the equivalent core temperature of the thermal center region inside the billet, including: Based on the mapping relationship, the hidden temperature points in different internal regions of the billet are inferred one by one to form a potential temperature state candidate set covering the central region and the boundary transition region of the billet. For each potential temperature state in the candidate temperature state set, the potential state is filtered according to the spatial connectivity of the heat transfer path inside the billet, and potential state points that are not sufficiently related to the thermal center region are excluded to obtain the target potential temperature state set. The target potential temperature state set is time-series aligned and stage-wise reorganized so that its transformation sequence in the sintering thermal history matches the formation process of the internal thermal center of the billet, forming a time-consistent state group. Based on the time-consistent state group, the equivalent core temperature representing the temperature of the thermal center region inside the billet is determined by comprehensively deriving multiple potential temperature states.

4. The intelligent control method for phosphate sintering temperature as described in claim 3, characterized in that, The equivalent core temperature is correlated with the furnace temperature parameters to generate a temperature gradient state variable, which, together with the equivalent core temperature, constitutes an equivalent temperature state model for the sintering process, including: The furnace temperature parameters are sorted into layers according to the distribution of heating zones, airflow path and billet arrangement, forming a layered set of temperature parameters. Based on the equivalent core temperature, the temperature parameter hierarchical set is correlated layer by layer to establish the correspondence between the equivalent core temperature and the temperature of different areas of the furnace. Based on the aforementioned correspondence, the temperature parameters of each layer of the furnace are reorganized according to the order of temperature elevation and spatial continuity to construct a temperature sequence state. The temperature sequence state is processed together with the equivalent core temperature to generate a temperature gradient state quantity, which, together with the equivalent core temperature, forms the equivalent temperature state model of the sintering process.

5. The intelligent control method for phosphate sintering temperature as described in claim 1, characterized in that, The equivalent temperature state model is analyzed to identify phase transformation characteristics of the phosphate system's dehydration and crystal phase transformation processes. Based on these phase transformation characteristics, a corresponding target sintering temperature trajectory is generated, including: The equivalent core temperature and temperature gradient state quantities in the equivalent temperature state model are analyzed in time segments, and the stages are divided according to the sintering thermal process to form a set of temperature state segments. Based on the temperature state segment set, the inflection points of temperature change, the sudden change trend of temperature gradient, and the characteristics of the stage-stable interval are extracted to generate a phase transition candidate characteristic set. The set of candidate phase transition features is classified and processed according to their order of appearance and duration in the thermal process. The features related to structural dehydration are distinguished from those related to crystal phase transformation, thus forming an initial set of phase transition features. The initial set of phase transition features is integrated and processed. Through comprehensive analysis of the continuity, repeatability and persistence of features in adjacent stages, the phase transition feature windows corresponding to the dehydration process and the crystal phase transformation process are determined. Based on the phase transformation feature window, a temperature trajectory structure is constructed in the order of heating, holding and cooling stages. The temperature change mode and stage boundary position of each stage are set to generate a target sintering temperature trajectory corresponding to the phase transformation feature information.

6. The intelligent control method for phosphate sintering temperature as described in claim 5, characterized in that, The initial set of phase transition characteristics is integrated, and through comprehensive analysis of the continuity, repeatability, and persistence of characteristics in adjacent stages, phase transition characteristic windows corresponding to the dehydration process and the crystal phase transformation process are determined, including: The feature characteristics from adjacent thermal processes in the initial set of phase transition features are compared one by one to determine their consistency at the stage boundary, thus forming a candidate set of stage connection. Screen the feature signs that appear with a frequency higher than a preset value or have a continuous distribution in the candidate set of stage transitions, identify duplicate signs, and construct a target sign set with duplicate attribute identifiers. The target symptom set is organized by time structure. Based on the existence span and duration of each symptom in the thermal process, it is divided and combined into time segments to form a staged symptom combination. Based on the aforementioned staged characteristic combinations, the characteristic combinations related to the structural dehydration process and the characteristic combinations related to the crystal phase transformation process are separated to determine the phase transformation characteristic windows corresponding to the dehydration process and the crystal phase transformation process.

7. The intelligent control method for phosphate sintering temperature as described in claim 6, characterized in that, Based on the phase transformation feature window, a temperature trajectory structure is constructed in the order of heating, holding, and cooling stages. The temperature change mode and stage boundary position of each stage are set to generate a target sintering temperature trajectory corresponding to the phase transformation feature information, including: Each phase transition characteristic window is assigned to the heating stage, the holding stage, and the cooling stage according to its time position in the thermal history, forming a phase transition window stage assignment set. Based on the set of phase change window stages, multiple temperature anchor points and time anchor points corresponding to the edge of the phase change window are set in the heating stage, the heat preservation stage and the cooling stage, and the anchor points are combined to form a stage boundary anchor point sequence. For each stage boundary anchor point sequence, a nonlinear heating method is selected in the heating stage, a segmented holding or gradual change method is selected in the heat preservation stage, and a segmented cooling method is selected in the cooling stage. The method is then associated with the phase change characteristic window within that stage to form a combination of temperature change methods. Following the order of heating, holding, and cooling stages, the temperature change patterns of each stage are combined with the corresponding stage boundary anchor point sequence and continuously assembled along the time axis to generate the target sintering temperature trajectory corresponding to the phase transformation feature window in the entire thermal history.

8. The intelligent control method for phosphate sintering temperature as described in claim 1, characterized in that, Based on the target sintering temperature trajectory, intelligent control of the phosphate sintering process is performed, including: The target sintering temperature trajectory is divided into stages of heating, holding and cooling. For each stage, a corresponding trajectory reference value and stage switching condition are set to form a target trajectory reference set. During the phosphate sintering process, the real-time equivalent core temperature and temperature gradient state are obtained and matched segment by segment with the target trajectory reference set to generate temperature state matching results. Based on the temperature state matching results, deviation judgments are made for the heating, heat preservation and cooling stages respectively, and the corresponding adjustment trigger categories are determined according to the deviation judgment results; Based on the aforementioned adjustment trigger category, the joint adjustment amount is determined according to the stage attributes; After executing the joint adjustment, the real-time equivalent core temperature and temperature gradient state quantity are deviated again to complete the intelligent control of the phosphate sintering process.

9. The intelligent control method for phosphate sintering temperature as described in claim 8, characterized in that, Based on the aforementioned adjustment trigger category, the joint adjustment amount is determined according to the stage attributes, including: The different adjustment trigger categories generated in the heating stage, heat preservation stage and cooling stage are collected and processed, and each adjustment trigger category is mapped to a stage set with the same stage attribute to form a trigger category stage mapping relationship. For each set of stages in the trigger category stage mapping relationship, a priority sequence of stage control elements is formed based on the change pattern of the temperature trajectory within that stage. According to the priority sequence of the stage control elements, in each stage set, two or more means are selected from a variety of adjustment means for combination, and the combination is matched one-to-one with the corresponding adjustment trigger category to form a set of adjustment means combination within the stage. Based on the set of adjustment methods within the current stage, the adjustment trigger categories in the current stage are matched accordingly. By jointly setting the adjustment amplitude and adjustment order of the selected adjustment methods in the current stage, a joint adjustment amount is generated.

10. A smart control system for phosphate sintering temperature, used to implement the smart control method for phosphate sintering temperature according to any one of claims 1-9, characterized in that, include: Parameter acquisition module, model building module, trajectory generation module, and intelligent control module; The parameter acquisition module is used to acquire sintering parameters during the sintering process of phosphate green bodies; The model building module generates state variables of the equivalent core temperature of the billet and the temperature gradient of the furnace based on the collected sintering parameters, and constructs an equivalent temperature state model of the sintering process. The trajectory generation module is used to analyze the equivalent temperature state model, identify the phase transformation characteristics of the phosphate system dehydration and crystal phase transformation process, and generate the corresponding target sintering temperature trajectory based on the phase transformation characteristics. The intelligent control module is used to intelligently control the phosphate sintering process based on the target sintering temperature trajectory.

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