Multi-parameter collaborative optimization control method based on large-scale model refrigeration station terminal system

Abstract

The present invention relates to the field of online control technology and is a multi-parameter collaborative optimization control method based on a large-scale model refrigeration station terminal system. The specific method includes: evaluating the working coupling degree of the refrigeration station; deeply evaluating the working performance of the refrigeration station terminal system and estimating the optimization direction of the control strategy; calculating the load weights of the new and old terminals, actively compensating for the hydraulic imbalance between the new and old terminal systems, and selecting a combined optimization control mode for the terminal system based on the energy efficiency difference coefficient; continuously monitoring the compatibility of the new and old systems at the refrigeration station terminal, and when the monitoring result is incompatible, outputting the differentiated control parameters of the refrigeration station terminal system. The present invention solves the problem in the prior art of the lack of a dynamic collaborative optimization mechanism for the new and old terminals of the refrigeration station based on multi-dimensional parameter differences.

Description

Technical Field

[0001] The present invention relates to the technical field of online control and is a multi-parameter collaborative optimization control method based on a large-model refrigeration station terminal system. Background Art

[0002] During the upgrade and transformation of the refrigeration station system, the integration of new and old terminal equipment faces multiple technical challenges. In the existing technology, the refrigeration station terminal system usually adopts a global unified control strategy, which fails to fully consider the essential differences between the new and old equipment in terms of energy efficiency attenuation characteristics, hydraulic impedance and control response speed. As a result, the following problems will appear in the actual operation of the refrigeration station: First, the energy efficiency characteristics do not match. The new terminal equipment usually adopts high-efficiency heat exchange technology, and its energy efficiency attenuation presents linear characteristics, while the old equipment shows exponential decline due to aging. It is difficult to dynamically align the energy efficiency benchmarks of the two, resulting in an increase in the overall energy efficiency loss of the system; second, hydraulic loss The imbalance is aggravated, which is manifested in the fact that the new terminal adopts nonlinear valve characteristics, while the old equipment causes impedance drift due to pipeline scaling, branch flow distribution imbalance occurs frequently, and when the local pressure difference deviation rate exceeds 0.5, it is easy to cause water pump surge; in addition, there will be control timing conflict problems, which are specifically manifested in the fact that the new terminal has a response speed of milliseconds, and the old equipment has a control command asynchrony due to actuator hysteresis, which produces an overshoot of more than 25% when the load suddenly changes, which will seriously affect the temperature control accuracy of the refrigeration station system; in the existing technology, the optimization control of the refrigeration station terminal mostly relies on static weight distribution or a single control mode, and lacks a dynamic coordination mechanism for multi-dimensional parameter differences. Summary of the Invention

[0003] The technical problem to be solved by the present invention is that the existing technology lacks a dynamic collaborative optimization mechanism for the new and old terminals of the refrigeration station based on multi-dimensional parameter differences. A multi-parameter collaborative optimization control method based on a large-model refrigeration station terminal system is proposed.

[0004] In order to achieve the above-mentioned object, the technical solution of the multi-parameter collaborative optimization control method based on the large-scale model refrigeration station terminal system of the present invention includes the following steps:

[0005] S1: Collect the operating characteristic data of the new and old terminal systems of the refrigeration station and evaluate the working coupling degree of the refrigeration station;

[0006] S2: In-depth evaluation of the performance of the refrigeration station terminal system, obtaining the energy efficiency difference coefficient and flow distribution coordination coefficient, and simultaneously constructing a multi-dimensional parameter comparison matrix to estimate the optimization direction of the control strategy;

[0007] S3: Calculate the load weights of the new and old terminal systems through the load weight distribution model, actively compensate for the hydraulic imbalance between the new and old terminal systems, and select the combined optimization control mode of the terminal system based on the energy efficiency difference coefficient;

[0008] S4: Continuously monitor the compatibility of the old and new systems at the end of the refrigeration station. When the monitoring result is incompatible, output the differentiated control parameters of the refrigeration station end system, and simultaneously visualize the fusion coefficient of the refrigeration station end system and the high-risk nodes of hydraulic imbalance in real time.

[0009] Specifically, S1 includes:

[0010] S11: Build an energy efficiency attenuation model for the new terminal of the refrigeration station, collect the factory energy efficiency value and actual operating time of the new terminal system of the refrigeration station and input them into the energy efficiency attenuation model, and output the actual energy efficiency value of the new terminal of the refrigeration station;

[0011] Preferably, the output formula of the energy efficiency attenuation model is:

[0012] ;

[0013] in, The factory energy efficiency value of the new terminal system of the refrigeration station;

[0014] The real-time operating time of the new terminal system of the refrigeration station;

[0015] Design life cycle for new terminal systems in refrigeration stations;

[0016] Obtain the measured pressure difference data and nominal flow data of the new terminal system of the refrigeration station, establish the valve flow characteristic curve of the new terminal system of the refrigeration station, and obtain the current effective energy efficiency value of the new terminal system of the refrigeration station ;

[0017] Preferably, the valve flow characteristic curve is specifically: ;

[0018] in, are the discharge coefficient and nonlinear index, respectively;

[0019] The pressure difference between the two ends of the valve at the new end of the refrigeration station;

[0020] S12: Collect historical energy efficiency records, real-time operating resistance, and valve actuator response delay of the old terminal system of the refrigeration station, and perform fitting processing on the energy efficiency decay trajectory of the old terminal system of the refrigeration station based on the collected data to obtain the actual energy efficiency value of the old terminal of the refrigeration station;

[0021] Preferably, the fitting process includes: ;

[0022] is the initial energy efficiency value of the old terminal system of the refrigeration station;

[0023] The accumulated operating time of the old terminal system of the refrigeration station;

[0024] is the attenuation coefficient of the old terminal system of the refrigeration station;

[0025] At the same time, the real-time operating resistance of the old terminal system of the refrigeration station is collected, and the hydraulic impedance change rate of the old terminal system of the refrigeration station is calculated based on the real-time operating resistance of the old terminal system of the refrigeration station and the design pressure loss of the new terminal system of the refrigeration station.

[0026] Preferably, the calculation strategy of the hydraulic impedance change rate is:

[0027] ;

[0028] in, The operating resistance of the old terminal system of the refrigeration station;

[0029] The design pressure loss of the new terminal system of the refrigeration station;

[0030] Specifically, S1 also includes:

[0031] S13: Conduct hydraulic coupling evaluation and thermal coupling evaluation on the working coupling degree of the refrigeration station to obtain the hydraulic imbalance index and thermal interference coefficient of the terminal system of the refrigeration station;

[0032] The hydraulic coupling degree evaluation includes: evaluating the branch pressure difference deviation rate at the end of the refrigeration station, and calculating the hydraulic imbalance index of the refrigeration station terminal system based on the branch pressure difference deviation rate at the end of the refrigeration station. , specifically:

[0033] ;

[0034] in, is the real-time flow of the i-th branch; is the total flow of the current refrigeration station terminal system;

[0035] Preferably, the branch pressure difference deviation rate of the new terminal of the refrigeration station is Specifically:

[0036] ;in, is the real-time pressure difference of the i-th branch; is the average pressure difference of the current refrigeration station terminal system;

[0037] It should be noted that the hydraulic imbalance index , which is used to quantify the hydraulic conflict intensity between the new and old terminals and can avoid imbalance in branch flow due to impedance differences.

[0038] The thermal coupling degree evaluation includes: quantifying the temperature gradient field of the refrigeration station terminal system, and calculating the thermal interference coefficient based on the temperature gradient field of the refrigeration station terminal system. , where the thermal interference coefficient is the ratio of the maximum temperature gradient to the average temperature gradient;

[0039] Preferably, the temperature gradient field The quantification includes:

[0040] ;in, Indicates the difference in water outlet temperature between adjacent terminals; Indicates the end spacing;

[0041] It should be noted that the thermal interference coefficient Used to capture the cascade effect of thermal interference and prevent local temperature field distortion.

[0042] Specifically, S2 includes:

[0043] S21: Conduct an in-depth analysis of the energy efficiency matching of the refrigeration station terminal system, specifically:

[0044] Extracting real-time energy efficiency of new terminal of refrigeration station , Corrected energy efficiency of old terminals and benchmark energy efficiency of cooling systems , and calculate the energy efficiency difference coefficient, and extract the hydraulic imbalance index Correcting the energy efficiency difference coefficient to obtain a corrected energy efficiency difference coefficient;

[0045] Preferably, the calculation strategy of the energy efficiency difference coefficient is:

[0046] ;

[0047] Preferably, the hydraulic imbalance index The specific corrections to the energy efficiency difference coefficient are as follows:

[0048] ;

[0049] S22: Extract the corrected energy efficiency difference coefficient and evaluate the energy efficiency integration requirement level of the cooling station terminal, including:

[0050] when When ≤10%, it means that the new terminal system and the old terminal system of the refrigeration station are directly compatible;

[0051] When 10%< When ≤25%, it means that the terminal system of the refrigeration station needs dynamic compensation;

[0052] when When it is >25%, it means that the control strategy of the refrigeration station terminal system needs to be reconstructed;

[0053] S23: Conduct an in-depth analysis of the hydraulic coordination of the refrigeration station terminal system, specifically:

[0054] Collect new terminal branch flow , old terminal branch flow and total system flow , and calculate the flow distribution coordination coefficient;

[0055] Preferably, the flow distribution coordination coefficient The calculation strategy is:

[0056] ;

[0057] in, are the lengths of the new terminal branch and the old terminal branch of the refrigeration station respectively;

[0058] L is the average length of all terminal branches in the refrigeration station;

[0059] S24: Extracting the flow distribution coordination coefficient and determining the hydraulic fusion state at the end of the refrigeration station, including:

[0060] when When ≥0.9, it means that the new terminal system and the old terminal system of the refrigeration station are well compatible;

[0061] When 0.7≤ When <0.9, it means that valve compensation is required for the terminal system of the refrigeration station;

[0062] when When <0.7, it indicates that water pump frequency conversion intervention is required for the refrigeration station terminal system.

[0063] Specifically, S2 also includes:

[0064] S25: collecting characteristic parameters of the new terminal of the refrigeration station and characteristic parameters of the old terminal of the refrigeration station, establishing a multi-dimensional parameter comparison matrix, and calculating the dimensional difference index of the refrigeration station terminal system;

[0065] The optimization direction of the control strategy is estimated based on the dimensional difference index of the refrigeration station terminal system, including:

[0066] when When , the temperature difference balance model of the refrigeration station terminal system is rebuilt;

[0067] when When updating, the hydraulic calculation algorithm of the refrigeration station terminal system is updated;

[0068] when When , a hybrid control sequence is used for the terminal system of the refrigeration station;

[0069] The characteristic parameters of the new terminal of the refrigeration station include: heat exchange temperature difference , valve gain and control response time The characteristic parameters of the old terminal of the refrigeration station include: heat transfer coefficient , pipeline impedance and PID dead zone ;

[0070] Preferably, the multidimensional parameter comparison matrix is ​​specifically: ;

[0071] The calculation strategy of the dimensional difference index of the refrigeration station terminal system is specifically as follows:

[0072] ;

[0073] are the measured values ​​and design values ​​of the characteristic parameters of the new terminal of the refrigeration station respectively;

[0074] are the measured values ​​and design values ​​of the characteristic parameters of the old terminal of the refrigeration station respectively;

[0075] k is the horizontal data index of the multidimensional parameter comparison matrix;

[0076] Specifically, S3 includes:

[0077] S31: Collect the running-in time of the new terminal of the refrigeration station and design life , new terminal real-time energy efficiency , theoretical maximum And the old terminal's cumulative running time ;

[0078] Construct a load weight distribution model to dynamically distribute the weights of the new and old terminals of the refrigeration station, and obtain the load weights of the new terminal system and the load weights of the old terminal system of the refrigeration station;

[0079] Preferably, the dynamic allocation is specifically:

[0080] , ;

[0081] Generate dynamic load distribution instructions according to the load weight of the new terminal system of the refrigeration station and the load weight of the old terminal system of the refrigeration station;

[0082] Preferably, the load of the new terminal system of the refrigeration station is the product of the load weight of the new terminal system of the refrigeration station and the total flow of the refrigeration station;

[0083] Preferably, the load of the old terminal system of the refrigeration station is the sedimentation of the load weight of the old terminal system of the refrigeration station and the total flow of the refrigeration station;

[0084] S32: Collect the branch flow of the new terminal system of the refrigeration station and old terminal system branch flow , and the new terminal system branch impedance Branch impedance of the old terminal system ;

[0085] The system generates a water pump compensation frequency based on the collected data, and outputs variable frequency pump adjustment instructions through the water pump compensation frequency to actively compensate for the pressure difference offset caused by the hydraulic imbalance between the new and old terminal systems of the refrigeration station;

[0086] Preferably, the water pump compensation frequency The calculation strategy is as follows:

[0087] ;

[0088] in, is the original proportional gain;

[0089] S33: Input the energy efficiency difference coefficient into the optimization control model, and output a combined optimization control mode corresponding to the energy efficiency difference coefficient;

[0090] Preferably, the control mode includes:

[0091] When the energy efficiency difference coefficient is greater than 0.2, the MPC model predictive control is adopted for the new terminal system of the refrigeration station, and the fuzzy PID control is adopted for the old terminal system of the refrigeration station;

[0092] When the energy efficiency difference coefficient is greater than 0.1 but less than or equal to 0.2, feedforward-feedback composite control is adopted for the new terminal system of the refrigeration station, and gain scheduling PID is adopted for the old terminal system of the refrigeration station;

[0093] When the energy efficiency difference coefficient is less than or equal to 0.1, adaptive robust control is adopted for the new terminal system of the refrigeration station, and traditional PID control is adopted for the old terminal system of the refrigeration station;

[0094] Specifically, S4 includes:

[0095] S41: Calculate and obtain the fusion coefficient of the current refrigeration station terminal system through the refrigeration station terminal system fusion evaluation strategy. The refrigeration station terminal system fusion evaluation strategy is specifically as follows:

[0096] ;

[0097] is the fusion coefficient of the refrigeration station terminal system;

[0098] It should be noted that the fusion coefficient of the refrigeration station terminal system is used to measure the compatibility and degree of integration between the new and old systems.

[0099] Assign coordination coefficients to flows;

[0100] It should be noted that the flow distribution coordination coefficient reflects the characteristics of the fluid flow in the system. The closer the value is to 0.8, the more matched the hydraulic characteristics are. Among them, 0.8 is obtained through fitting.

[0101] Actual system efficiency, which indicates the operating efficiency of the current refrigeration station terminal system;

[0102] Design efficiency refers to the efficiency of the refrigeration station terminal system under ideal conditions.

[0103] S42: real-time monitoring of the fusion coefficient of the refrigeration station terminal system. When the fusion coefficient of the refrigeration station terminal system is greater than or equal to 0.75, it is determined that the new terminal and the old terminal of the refrigeration station are compatible.

[0104] When the fusion coefficient of the refrigeration station terminal system is less than 0.75, it is determined that the new terminal and the old terminal of the refrigeration station terminal are incompatible, and step S43 is executed at the same time to output the differentiated control parameters of the refrigeration station terminal system;

[0105] S43: Calculate and output differentiated control parameters of the refrigeration station terminal system, where the differentiated control parameters include: a new terminal optimized control parameter set and an old terminal optimized control parameter set;

[0106] S44: Synchronously output the predictive control parameter set and real-time valve opening adjustment instruction of the new terminal system of the refrigeration station and the PID parameter set after compensation of the old terminal of the refrigeration station.

[0107] Specifically, S4 also includes:

[0108] S45: Real-time monitoring of the fusion coefficient at the end of the refrigeration station and visualization through a heat map;

[0109] S46: Synchronously monitor the hydraulic characteristic coefficients in the refrigeration station system and mark high-risk nodes of hydraulic imbalance in real time.

[0110] Compared with the prior art, the technical effects of the present invention are as follows:

[0111] 1. This invention establishes a new terminal energy efficiency attenuation model and fits it with the old terminal decay trajectory, dynamically calculates the energy efficiency difference coefficient, and corrects it in combination with the hydraulic imbalance index. This achieves dynamic alignment of the energy efficiency benchmarks of new and old equipment, thereby improving the overall energy efficiency of the refrigeration station system, which is superior to the improvement achieved by traditional static allocation strategies.

[0112] 2. Based on the flow distribution coordination coefficient and pressure difference compensation algorithm, the present invention adjusts the frequency of the variable frequency pump and the valve opening in real time, controls the branch pressure difference deviation rate to below 0.3, and effectively eliminates the risk of local flow oscillation and water pump surge.

[0113] 3. The present invention evaluates the differences in thermal, hydraulic and control dimensions through a multi-dimensional parameter comparison matrix, and triggers a hierarchical control strategy (MPC / fuzzy PID / robust control) in combination with the energy efficiency difference coefficient, thereby shortening the response time of the new terminal and reducing the overshoot of the old terminal, while also improving the temperature control accuracy of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0114] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them:

[0115] Figure 1 It is a flow chart of the multi-parameter collaborative optimization control method based on the large-model refrigeration station terminal system of the present invention. DETAILED DESCRIPTION

[0116] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0117] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0118] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0119] Example 1:

[0120] like Figure 1As shown, the multi-parameter collaborative optimization control method based on the large model refrigeration station terminal system of the embodiment of the present invention is as follows Figure 1 As shown, the specific steps are as follows:

[0121] S1: Collect the operating characteristic data of the new and old terminal systems of the refrigeration station and evaluate the working coupling degree of the refrigeration station;

[0122] S1 includes:

[0123] S11: Build an energy efficiency attenuation model for the new terminal of the refrigeration station, collect the factory energy efficiency value and actual operating time of the new terminal system of the refrigeration station and input them into the energy efficiency attenuation model, and output the actual energy efficiency value of the new terminal of the refrigeration station;

[0124] Preferably, the output formula of the energy efficiency attenuation model is:

[0125] ;

[0126] in, The factory energy efficiency value of the new terminal system of the refrigeration station;

[0127] The real-time operating time of the new terminal system of the refrigeration station;

[0128] Design life cycle for new terminal systems in refrigeration stations;

[0129] Obtain the measured pressure difference data and nominal flow data of the new terminal system of the refrigeration station, establish the valve flow characteristic curve of the new terminal system of the refrigeration station, and obtain the current effective energy efficiency value of the new terminal system of the refrigeration station ;

[0130] Preferably, the valve flow characteristic curve is specifically: ;

[0131] in, are the discharge coefficient and nonlinear index, respectively;

[0132] The pressure difference between the two ends of the valve at the new end of the refrigeration station;

[0133] S12: Collect historical energy efficiency records, real-time operating resistance, and valve actuator response delay of the old terminal system of the refrigeration station, and perform fitting processing on the energy efficiency decay trajectory of the old terminal system of the refrigeration station based on the collected data to obtain the actual energy efficiency value of the old terminal of the refrigeration station;

[0134] Preferably, the fitting process includes: ;

[0135] is the initial energy efficiency value of the old terminal system of the refrigeration station;

[0136] The accumulated operating time of the old terminal system of the refrigeration station;

[0137] is the attenuation coefficient of the old terminal system of the refrigeration station;

[0138] At the same time, the real-time operating resistance of the old terminal system of the refrigeration station is collected, and the hydraulic impedance change rate of the old terminal system of the refrigeration station is calculated based on the real-time operating resistance of the old terminal system of the refrigeration station and the design pressure loss of the new terminal system of the refrigeration station.

[0139] Preferably, the calculation strategy of the hydraulic impedance change rate is:

[0140] ;

[0141] in, The operating resistance of the old terminal system of the refrigeration station;

[0142] The design pressure loss of the new terminal system of the refrigeration station;

[0143] The S1 also includes:

[0144] S13: Conduct hydraulic coupling evaluation and thermal coupling evaluation on the working coupling degree of the refrigeration station to obtain the hydraulic imbalance index and thermal interference coefficient of the terminal system of the refrigeration station;

[0145] The hydraulic coupling degree evaluation includes: evaluating the branch pressure difference deviation rate at the end of the refrigeration station, and calculating the hydraulic imbalance index of the refrigeration station terminal system based on the branch pressure difference deviation rate at the end of the refrigeration station. , specifically:

[0146] ;

[0147] in, is the real-time flow of the i-th branch; is the total flow of the current refrigeration station terminal system;

[0148] Preferably, the branch pressure difference deviation rate of the new terminal of the refrigeration station is Specifically:

[0149] ;in, is the real-time pressure difference of the i-th branch; is the average pressure difference of the current refrigeration station terminal system;

[0150] It should be noted that the hydraulic imbalance index , which is used to quantify the hydraulic conflict intensity between the new and old terminals and can avoid imbalance in branch flow due to impedance differences.

[0151] The thermal coupling degree evaluation includes: quantifying the temperature gradient field of the refrigeration station terminal system, and calculating the thermal interference coefficient based on the temperature gradient field of the refrigeration station terminal system. , where the thermal interference coefficient is the ratio of the maximum temperature gradient to the average temperature gradient;

[0152] Preferably, the temperature gradient field The quantification includes:

[0153] ;in, Indicates the difference in water outlet temperature between adjacent terminals; Indicates the end spacing;

[0154] It should be noted that the thermal interference coefficient Used to capture the cascade effect of thermal interference and prevent local temperature field distortion.

[0155] S2: In-depth evaluation of the performance of the refrigeration station terminal system, obtaining the energy efficiency difference coefficient and flow distribution coordination coefficient, and simultaneously constructing a multi-dimensional parameter comparison matrix to estimate the optimization direction of the control strategy;

[0156] S2 includes:

[0157] S21: Conduct an in-depth analysis of the energy efficiency matching of the refrigeration station terminal system, specifically:

[0158] Extracting real-time energy efficiency of new terminal of refrigeration station , Corrected energy efficiency of old terminals and benchmark energy efficiency of cooling systems , and calculate the energy efficiency difference coefficient, and extract the hydraulic imbalance index Correcting the energy efficiency difference coefficient to obtain a corrected energy efficiency difference coefficient;

[0159] Preferably, the calculation strategy of the energy efficiency difference coefficient is:

[0160] ;

[0161] Preferably, the hydraulic imbalance index The specific corrections to the energy efficiency difference coefficient are as follows:

[0162] ;

[0163] S22: Extract the corrected energy efficiency difference coefficient and evaluate the energy efficiency integration requirement level of the cooling station terminal, including:

[0164] when When ≤10%, it means that the new terminal system and the old terminal system of the refrigeration station are directly compatible;

[0165] When 10%< When ≤25%, it means that the terminal system of the refrigeration station needs dynamic compensation;

[0166] when When it is >25%, it means that the control strategy of the refrigeration station terminal system needs to be reconstructed;

[0167] S23: Conduct an in-depth analysis of the hydraulic coordination of the refrigeration station terminal system, specifically:

[0168] Collect new terminal branch flow , old terminal branch flow and total system flow , and calculate the flow distribution coordination coefficient;

[0169] Preferably, the flow distribution coordination coefficient The calculation strategy is:

[0170] ;

[0171] in, are the lengths of the new terminal branch and the old terminal branch of the refrigeration station respectively;

[0172] L is the average length of all terminal branches in the refrigeration station;

[0173] S24: Extracting the flow distribution coordination coefficient and determining the hydraulic fusion state at the end of the refrigeration station, including:

[0174] when When ≥0.9, it means that the new terminal system and the old terminal system of the refrigeration station are well compatible;

[0175] When 0.7≤ When <0.9, it means that valve compensation is required for the terminal system of the refrigeration station;

[0176] when When <0.7, it indicates that water pump frequency conversion intervention is required for the refrigeration station terminal system.

[0177] S2 also includes:

[0178] S25: collecting characteristic parameters of the new terminal of the refrigeration station and characteristic parameters of the old terminal of the refrigeration station, establishing a multi-dimensional parameter comparison matrix, and calculating the dimensional difference index of the refrigeration station terminal system;

[0179] The optimization direction of the control strategy is estimated based on the dimensional difference index of the refrigeration station terminal system, including:

[0180] when When , the temperature difference balance model of the refrigeration station terminal system is rebuilt;

[0181] when When updating, the hydraulic calculation algorithm of the refrigeration station terminal system is updated;

[0182] when When , a hybrid control sequence is used for the terminal system of the refrigeration station;

[0183] The characteristic parameters of the new terminal of the refrigeration station include: heat exchange temperature difference , valve gain and control response time The characteristic parameters of the old terminal of the refrigeration station include: heat transfer coefficient , pipeline impedance and PID dead zone ;

[0184] Preferably, the multidimensional parameter comparison matrix is ​​specifically: ;

[0185] The calculation strategy of the dimensional difference index of the refrigeration station terminal system is specifically as follows:

[0186] ;

[0187] are the measured values ​​and design values ​​of the characteristic parameters of the new terminal of the refrigeration station respectively;

[0188] are the measured values ​​and design values ​​of the characteristic parameters of the old terminal of the refrigeration station respectively;

[0189] k is the horizontal data index of the multidimensional parameter comparison matrix;

[0190] Exemplarily, in this embodiment, k represents the thermal, hydraulic, and response dimensions, respectively;

[0191] S3: Calculate the load weights of the new and old terminal systems through the load weight distribution model, actively compensate for the hydraulic imbalance between the new and old terminal systems, and select the combined optimization control mode of the terminal system based on the energy efficiency difference coefficient;

[0192] S3 includes:

[0193] S31: Collect the running-in time of the new terminal of the refrigeration station and design life , new terminal real-time energy efficiency , theoretical maximum And the old terminal's cumulative running time ;

[0194] Construct a load weight distribution model to dynamically distribute the weights of the new and old terminals of the refrigeration station, and obtain the load weights of the new terminal system and the load weights of the old terminal system of the refrigeration station;

[0195] Preferably, the dynamic allocation is specifically:

[0196] , ;

[0197] Generate dynamic load distribution instructions according to the load weight of the new terminal system of the refrigeration station and the load weight of the old terminal system of the refrigeration station;

[0198] Preferably, the load of the new terminal system of the refrigeration station is the product of the load weight of the new terminal system of the refrigeration station and the total flow of the refrigeration station;

[0199] Preferably, the load of the old terminal system of the refrigeration station is the sedimentation of the load weight of the old terminal system of the refrigeration station and the total flow of the refrigeration station;

[0200] S32: Collect the branch flow of the new terminal system of the refrigeration station and old terminal system branch flow , and the new terminal system branch impedance Branch impedance of the old terminal system ;

[0201] The system generates a water pump compensation frequency based on the collected data, and outputs variable frequency pump adjustment instructions through the water pump compensation frequency to actively compensate for the pressure difference offset caused by the hydraulic imbalance between the new and old terminal systems of the refrigeration station;

[0202] Preferably, the water pump compensation frequency The calculation strategy is as follows:

[0203] ;

[0204] in, is the original proportional gain;

[0205] S33: Input the energy efficiency difference coefficient into the optimization control model, and output a combined optimization control mode corresponding to the energy efficiency difference coefficient;

[0206] Preferably, the control mode includes:

[0207] When the energy efficiency difference coefficient is greater than 0.2, the MPC model predictive control is adopted for the new terminal system of the refrigeration station, and the fuzzy PID control is adopted for the old terminal system of the refrigeration station;

[0208] For example, in this embodiment, it should be noted that:

[0209] When the energy efficiency difference coefficient is greater than 0.2, the energy efficiency difference between the old and new terminal systems of the refrigeration station is significant. The high efficiency characteristics of the new terminal system of the refrigeration station need to be fully utilized. Through rolling optimization and future state prediction through the MPC model, the dynamic energy efficiency advantages of the new terminal can be maximized.

[0210] For the old terminal system of the refrigeration station, there are response hysteresis and nonlinearity. Fuzzy PID dynamically adjusts PID parameters through the rule base, which can well adapt to the nonlinear characteristics of the old equipment.

[0211] When the energy efficiency difference coefficient is greater than 0.1 but less than or equal to 0.2, feedforward-feedback composite control is adopted for the new terminal system of the refrigeration station, and gain scheduling PID is adopted for the old terminal system of the refrigeration station;

[0212] For example, in this embodiment, it should be noted that:

[0213] When the energy efficiency difference coefficient is greater than 0.1 but less than or equal to 0.2, the energy efficiency difference between the new and old terminal systems of the refrigeration station is moderate. Feedforward-feedback composite control is adopted for the new terminal system of the refrigeration station. Feedforward control quickly responds to setpoint changes (taking advantage of the high efficiency of the new terminal), and feedback control suppresses disturbances (such as flow fluctuations of the old terminal). This is suitable for scenarios with moderate energy efficiency differences and avoids excessive computational overhead of MPC.

[0214] For the old terminal system of the refrigeration station, the gain scheduling PID is adopted to effectively solve the nonlinear problem of the old equipment under partial load.

[0215] When the energy efficiency difference coefficient is less than or equal to 0.1, adaptive robust control is adopted for the new terminal system of the refrigeration station, and traditional PID control is adopted for the old terminal system of the refrigeration station;

[0216] For example, in this embodiment, it should be noted that:

[0217] When the energy efficiency difference coefficient is less than or equal to 0.1, the energy efficiency difference between the old and new terminal systems of the refrigeration station is small, the performance of the old terminal system of the refrigeration station is close to that of the new terminal system, and the traditional PID is sufficient to maintain stable operation.

[0218] S4: Continuously monitor the compatibility of the old and new systems at the end of the refrigeration station. When the monitoring result is incompatible, output the differentiated control parameters of the refrigeration station end system, and simultaneously visualize the fusion coefficient of the refrigeration station end system and the high-risk nodes of hydraulic imbalance in real time.

[0219] S4 includes:

[0220] S41: Calculate and obtain the fusion coefficient of the current refrigeration station terminal system through the refrigeration station terminal system fusion evaluation strategy. The refrigeration station terminal system fusion evaluation strategy is specifically as follows:

[0221] ;

[0222] is the fusion coefficient of the refrigeration station terminal system;

[0223] It should be noted that the fusion coefficient of the refrigeration station terminal system is used to measure the compatibility and degree of integration between the new and old systems.

[0224] Assign coordination coefficients to flows;

[0225] It should be noted that the flow distribution coordination coefficient reflects the characteristics of the fluid flow in the system. The closer the value is to 0.8, the more matched the hydraulic characteristics are. Among them, 0.8 is obtained through fitting.

[0226] Actual system efficiency, which indicates the operating efficiency of the current refrigeration station terminal system;

[0227] Design efficiency refers to the efficiency of the refrigeration station terminal system under ideal conditions.

[0228] S42: real-time monitoring of the fusion coefficient of the refrigeration station terminal system. When the fusion coefficient of the refrigeration station terminal system is greater than or equal to 0.75, it is determined that the new terminal and the old terminal of the refrigeration station are compatible.

[0229] When the fusion coefficient of the refrigeration station terminal system is less than 0.75, it is determined that the new terminal and the old terminal of the refrigeration station terminal are incompatible, and step S43 is executed at the same time to output the differentiated control parameters of the refrigeration station terminal system;

[0230] S43: Calculate and output differentiated control parameters of the refrigeration station terminal system, where the differentiated control parameters include: a new terminal optimized control parameter set and an old terminal optimized control parameter set;

[0231] S44: Synchronously output the predictive control (MPC) parameter set and real-time valve opening adjustment instructions of the new terminal system of the refrigeration station and the PID parameter set after compensation of the old terminal of the refrigeration station.

[0232] Exemplarily, in this embodiment, the new terminal optimization control parameter set includes: prediction time domain length and valve opening correction amount;

[0233] Among them, the predicted time domain length The calculation strategy is:

[0234] ;

[0235] It represents the temperature change of the new terminal, reflecting the change in temperature regulation of the new system;

[0236] is the temperature gradient of the new terminal working space of the refrigeration station, which represents the rate of change of temperature in space; Indicates the spatial flow rate of the new terminal system of the refrigeration station;

[0237] The calculation strategy of the valve opening correction amount is:

[0238] ;

[0239] It is the valve opening correction value, which is used to adjust the valve opening to achieve precise flow control;

[0240] is the proportional coefficient, which reflects the influence of the difference between the set flow rate and the actual flow rate on the adjustment of the valve opening;

[0241] To set the flow rate, it indicates the flow rate value that the system expects to achieve;

[0242] is the actual flow, indicating the current actual flow value of the system;

[0243] is the differential coefficient, which reflects the influence of the flow rate change rate on the valve opening adjustment;

[0244] is the flow rate change rate, which indicates the speed at which the flow changes over time.

[0245] Exemplarily, in this embodiment, the old terminal optimization control parameter set includes: a modified proportional gain, a modified integral time constant, and a modified differential time constant;

[0246] The calculation strategy of the modified proportional gain is:

[0247] ;

[0248] in, is the corrected proportional gain, which is used to improve the response speed and accuracy of the system; is the original proportional gain;

[0249] is the damping coefficient of the old terminal, reflecting the damping effect of the old terminal system of the refrigeration station during the control process; is the damping coefficient of the new terminal, reflecting the damping effect of the new terminal system of the refrigeration station during the control process;

[0250] The calculation strategy of the modified integral time constant is:

[0251] ;

[0252] The corrected integral time constant is used to eliminate the system steady-state error; Original integration time constant;

[0253] The calculation strategy of the modified differential time constant is:

[0254] ;

[0255] is the modified differential time constant, which is used to suppress overshoot and oscillation of the system.

[0256] is the original differential time constant;

[0257] The S4 also includes:

[0258] S45: Real-time monitoring of the fusion coefficient at the end of the refrigeration station and visualization through a heat map;

[0259] S46: Synchronously monitor the hydraulic characteristic coefficients in the refrigeration station system and mark high-risk nodes of hydraulic imbalance in real time.

[0260] Example 2:

[0261] This embodiment provides an electronic device, comprising: a processor and a memory, wherein the memory stores a computer program that can be called by the processor;

[0262] The processor executes the above-mentioned multi-parameter collaborative optimization control method based on the large-model refrigeration station terminal system by calling the computer program stored in the memory.

[0263] This electronic device may vary significantly due to different configurations or performance, and may include one or more processors (Central Processing Units, CPUs) and one or more memories, wherein the memories store at least one computer program, which is loaded and executed by the processor to implement the multi-parameter collaborative optimization control method based on a large-scale model refrigeration station terminal system provided in the above-mentioned method embodiment. The electronic device may also include other components for implementing the device's functions. For example, the electronic device may also have components such as wired or wireless network interfaces and input / output interfaces for data input and output. This embodiment will not be described in detail here.

[0264] Example 3:

[0265] This embodiment provides a computer-readable storage medium having a rewritable computer program stored thereon;

[0266] When the computer program runs on a computer device, the computer device is enabled to execute the above-mentioned multi-parameter collaborative optimization control method based on the large-model refrigeration station terminal system.

[0267] For example, computer-readable storage media can be read-only memory (ROM), random access memory (RAM), compact disc read-only memory (CD-ROM), magnetic tape, floppy disk, and optical data storage device.

[0268] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0269] It should be understood that determining B based on A does not mean determining B based solely on A. B can also be determined based on A and / or other information.

[0270] The above embodiments can be implemented in whole or in part via software, hardware, firmware, or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. A computer program product comprises one or more computer instructions or computer programs. When the computer instructions or computer program are loaded or executed on a computer, the processes or functions according to the embodiments of the present invention are fully or partially generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. Computer instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, computer instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center via a wired network or / and a wireless network. The computer-readable storage medium can be any available medium accessible by a computer or a data storage device such as a server or data center that contains a collection of one or more available media. Available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media. The semiconductor media can be a solid-state drive.

[0271] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in the present invention can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0272] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0273] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of units is only one type. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0274] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0275] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0276] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0277] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-parameter collaborative optimization control method based on a large-scale model refrigeration station terminal system is characterized by: include: S1: Collect the operating characteristic data of the new and old terminal systems of the refrigeration station and evaluate the working coupling degree of the refrigeration station; S2: In-depth evaluation of the performance of the refrigeration station terminal system, obtaining the energy efficiency difference coefficient and flow distribution coordination coefficient, and simultaneously constructing a multi-dimensional parameter comparison matrix to estimate the optimization direction of the control strategy; S21: Conduct an in-depth analysis of the energy efficiency matching of the refrigeration station terminal system, specifically: Extracting real-time energy efficiency of new terminal of refrigeration station , Corrected energy efficiency of old terminals and benchmark energy efficiency of cooling systems , and calculate the energy efficiency difference coefficient, and extract the hydraulic imbalance index Correcting the energy efficiency difference coefficient to obtain a corrected energy efficiency difference coefficient; S22: Extract the corrected energy efficiency difference coefficient and evaluate the energy efficiency integration requirement level of the cooling station terminal, including: when When ≤10%, it means that the new terminal system and the old terminal system of the refrigeration station are directly compatible; When 10%< When ≤25%, it means that the terminal system of the refrigeration station needs dynamic compensation; when When it is >25%, it means that the control strategy of the refrigeration station terminal system needs to be reconstructed; S23: Conduct an in-depth analysis of the hydraulic coordination of the refrigeration station terminal system, specifically: Collect new terminal branch flow , old terminal branch flow and total system flow , and calculate the flow distribution coordination coefficient; S24: Extracting flow distribution coordination coefficient , and determine the hydraulic fusion status of the refrigeration station end, including: when When ≥0.9, it means that the new terminal system and the old terminal system of the refrigeration station are well compatible; When 0.7≤ When <0.9, it means that valve compensation is required for the terminal system of the refrigeration station; when When <0.7, it indicates that the water pump frequency conversion intervention of the refrigeration station terminal system is required; S25: collecting characteristic parameters of the new terminal of the refrigeration station and characteristic parameters of the old terminal of the refrigeration station, establishing a multi-dimensional parameter comparison matrix, and calculating the dimensional difference index of the refrigeration station terminal system; The optimization direction of the control strategy is estimated based on the dimensional difference index of the refrigeration station terminal system, including: When the thermal dimension difference index When , the temperature difference balance model of the refrigeration station terminal system is rebuilt; When the hydraulic dimension difference index When updating, the hydraulic calculation algorithm of the refrigeration station terminal system is updated; When the response dimension difference index When , a hybrid control sequence is used for the terminal system of the refrigeration station; The characteristic parameters of the new terminal of the refrigeration station include: heat exchange temperature difference , valve gain and control response time The characteristic parameters of the old terminal of the refrigeration station include: heat transfer coefficient , pipeline impedance and PID dead zone ; S3: Calculate the load weights of the new and old terminal systems through the load weight distribution model, actively compensate for the hydraulic imbalance between the new and old terminal systems, and select the combined optimization control mode of the terminal system based on the energy efficiency difference coefficient; S4: Continuously monitor the compatibility of the old and new systems at the end of the refrigeration station. When the monitoring result is incompatible, output the differentiated control parameters of the refrigeration station end system, and simultaneously visualize the fusion coefficient of the refrigeration station end system and the high-risk nodes of hydraulic imbalance in real time.

2. The multi-parameter collaborative optimization control method based on a large-scale model refrigeration station terminal system according to claim 1 is characterized in that: S1 includes: S11: Build an energy efficiency attenuation model for the new terminal of the refrigeration station, collect the factory energy efficiency value and actual operating time of the new terminal system of the refrigeration station and input them into the energy efficiency attenuation model, and output the actual energy efficiency value of the new terminal of the refrigeration station; Obtain the measured pressure difference data and nominal flow data of the new terminal system of the refrigeration station, establish the valve flow characteristic curve of the new terminal system of the refrigeration station, and obtain the current effective energy efficiency value of the new terminal system of the refrigeration station ; S12: Collect historical energy efficiency records, real-time operating resistance, and valve actuator response delay of the old terminal system of the refrigeration station, and perform fitting processing on the energy efficiency decay trajectory of the old terminal system of the refrigeration station based on the collected data to obtain the actual energy efficiency value of the old terminal of the refrigeration station; At the same time, the real-time operating resistance of the old terminal system of the refrigeration station is collected, and the hydraulic impedance change rate of the old terminal system of the refrigeration station is calculated based on the real-time operating resistance of the old terminal system of the refrigeration station and the design pressure loss of the new terminal system of the refrigeration station.

3. The multi-parameter collaborative optimization control method based on a large-scale model refrigeration station terminal system according to claim 2 is characterized in that: The S1 also includes: S13: Conduct hydraulic coupling evaluation and thermal coupling evaluation on the working coupling degree of the refrigeration station to obtain the hydraulic imbalance index and thermal interference coefficient of the terminal system of the refrigeration station; The hydraulic coupling degree evaluation includes: evaluating the branch pressure difference deviation rate at the end of the refrigeration station, and calculating the hydraulic imbalance index of the refrigeration station terminal system based on the branch pressure difference deviation rate at the end of the refrigeration station. , specifically: ； in, is the real-time flow of the i-th branch; is the total flow of the current refrigeration station terminal system; The thermal coupling degree evaluation includes: quantifying the temperature gradient field of the refrigeration station terminal system, and calculating the thermal interference coefficient based on the temperature gradient field of the refrigeration station terminal system. , where the thermal interference coefficient is the ratio of the maximum temperature gradient to the average temperature gradient.

4. The multi-parameter collaborative optimization control method based on a large-scale model refrigeration station terminal system according to claim 3 is characterized in that S3 include: S31: Collect the running-in time of the new terminal of the refrigeration station and design life , new terminal real-time energy efficiency , theoretical maximum And the old terminal's cumulative running time ; Construct a load weight distribution model to dynamically distribute the weights of the new and old terminals of the refrigeration station, and obtain the load weights of the new terminal system and the load weights of the old terminal system of the refrigeration station; Generate dynamic load distribution instructions according to the load weight of the new terminal system of the refrigeration station and the load weight of the old terminal system of the refrigeration station; S32: Collect the branch flow of the new terminal system of the refrigeration station and old terminal system branch flow , and the new terminal system branch impedance Branch impedance of the old terminal system ; The system generates a water pump compensation frequency based on the collected data, and outputs variable frequency pump adjustment instructions through the water pump compensation frequency to actively compensate for the pressure difference offset caused by the hydraulic imbalance between the new and old terminal systems of the refrigeration station; S33: Input the energy efficiency difference coefficient into the optimization control model, and output the combined optimization control mode corresponding to the energy efficiency difference coefficient.

5. The multi-parameter collaborative optimization control method based on a large-scale model refrigeration station terminal system according to claim 4 is characterized in that S4 include: S41: Calculate and obtain the fusion coefficient of the current refrigeration station terminal system through the refrigeration station terminal system fusion evaluation strategy. The refrigeration station terminal system fusion evaluation strategy is specifically as follows: ； is the fusion coefficient of the refrigeration station terminal system; Assign coordination coefficients to flows; Actual system efficiency; Design efficiency; S42: monitoring the fusion coefficient of the refrigeration station terminal system in real time. When the fusion coefficient of the refrigeration station terminal system is greater than or equal to 0.75, determining whether the new terminal and the old terminal of the refrigeration station are compatible; When the fusion coefficient of the refrigeration station terminal system is less than 0.75, it is determined that the new terminal and the old terminal of the refrigeration station terminal are incompatible, and step S43 is executed at the same time to output the differentiated control parameters of the refrigeration station terminal system; S43: Calculate and output differentiated control parameters of the refrigeration station terminal system, where the differentiated control parameters include: a new terminal optimized control parameter set and an old terminal optimized control parameter set; S44: Synchronously output the predictive control parameter set and real-time valve opening adjustment instruction of the new terminal system of the refrigeration station and the PID parameter set after compensation of the old terminal of the refrigeration station.

6. The multi-parameter collaborative optimization control method based on a large-scale model refrigeration station terminal system according to claim 5 is characterized in that: The S4 also includes: S45: Real-time monitoring of the fusion coefficient at the end of the refrigeration station and visualization through heat maps; S46: Synchronously monitor the hydraulic characteristic coefficients in the refrigeration station system and mark high-risk nodes of hydraulic imbalance in real time.

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