Commercial refrigerator-based inverter compressor control optimization method

Abstract

The invention discloses an inverter compressor control optimization method based on a commercial refrigerator, and relates to the technical field of refrigeration optimization control, the commercial refrigerator is divided into a plurality of independent temperature control areas, monitoring points are deployed in each area, and refined temperature control and load management are realized; according to the method, the load condition of each temperature control area is recognized through a load index Fzzs, i calculation method of the ith temperature control area based on the cargo load and manual operation behaviors, the dynamic refrigeration requirement of the refrigerator is met by adjusting the refrigerant flow, precise control over each temperature control area is achieved by adopting the refrigerant flow adjusting index Radj, and compared with traditional fixed-frequency compressor adjustment, the dynamic refrigeration requirement of the refrigerator is met. And the refrigerating capacity can be flexibly adjusted according to real-time requirements. And the evaporation pressure and the condensation pressure are monitored through the pressure stability index, an optimization instruction is automatically triggered, the operation parameters of the inverter compressor are adjusted, the refrigerant flow is synchronously optimized, and refrigeration balance of all the areas is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigeration optimization control, and specifically to an optimization method for controlling a variable-frequency compressor based on a commercial freezer. Background Art

[0002] With the continuous development of commercial freezer technology and the increasing application requirements, traditional commercial freezers are facing greater challenges in terms of energy efficiency, operating efficiency, temperature control accuracy, and environmental adaptability. Traditional freezers usually adopt a single compressor and refrigeration system, and do not fully consider the temperature fluctuations and load differences in different regions inside the freezer, resulting in low overall energy efficiency and sub-optimal refrigeration effects. In addition, the refrigeration efficiency of the freezer is usually affected by factors such as the external environmental temperature, cargo storage requirements, and manual operations. The changes in these factors make it difficult for the freezer system to achieve efficient and stable temperature control management, further affecting the operating stability and product quality of the freezer.

[0003] To address these problems, variable-frequency compressors, as a high-efficiency control device, have gradually been widely used in commercial freezers. By adjusting the rotational speed of the compressor, the variable-frequency compressor can control the refrigerant flow rate and the temperature in the temperature control area, and can perform precise adjustment according to actual needs, avoiding energy waste of traditional fixed-frequency compressors during load fluctuations. However, although the introduction of variable-frequency compressors has improved the energy efficiency of the freezer to a certain extent, traditional commercial freezers still have the following problems: First, the load distribution in the temperature control area is uneven, resulting in possible overcooling or overheating in some areas of the freezer; second, there is a lack of comprehensive optimization management of multiple factors (such as cargo load, manual operation behavior, external environment, etc.), and it is impossible to effectively achieve temperature control balance between regions; third, it is often difficult to synergistically optimize the compressor frequency adjustment and refrigerant flow rate adjustment, resulting in limited room for improving refrigeration efficiency. Summary of the Invention

[0004] In view of the deficiencies of the prior art, the present invention provides an optimization method for controlling a variable-frequency compressor based on a commercial freezer to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention is realized through the following technical solutions: An optimization method for controlling a variable-frequency compressor based on a commercial freezer includes the following steps:

[0006] S1. Divide the interior of the commercial freezer into several temperature control areas in advance according to levels, and set monitoring points in each temperature control area to collect and obtain the operating parameters in each temperature control area, including the evaporation temperature Te of the i-th temperature control area i , the condensation temperature Tc i , the compressor frequency F compressor,i , the refrigerant flow rate M i , the evaporation pressure P evap,iand the condensation pressure P cond,i , establish a set of operating parameters;

[0007] S2. Collect the cargo load information and manual operation behavior information in the temperature-controlled area, establish a regional load set, and calculate based on the regional load set to obtain the load index Fi of the ith temperature-controlled area zzs,i , and preset a load level threshold to identify the operating load level of the ith temperature-controlled area from the current state, and generate a corresponding first strategy or second strategy. After implementation, construct the operating state coefficient Li of the ith temperature-controlled area hxs,i , and preset a state efficiency threshold. If the operating state coefficient Li of the ith temperature-controlled area hxs,i is lower than the state efficiency threshold, trigger a first optimization instruction;

[0008] S3. After receiving the first optimization instruction, extract the evaporation temperature Te of the ith temperature-controlled area from the set of operating parameters obtained in step S1 i , the condensation temperature Tc i and the compressor frequency F compressor,i , calculate the refrigerant flow rate adjustment index R_adj, and based on the refrigerant flow rate adjustment index R_adj, obtain the adjusted new refrigerant flow rate Mi of the ith temperature-controlled area new,i to match the refrigeration demand of the freezer;

[0009] S4. Real-time monitor the evaporation pressure Pi evap,i and the condensation pressure P cond,i of the ith temperature-controlled area, generate the pressure stability index Pi stb,i of the ith temperature-controlled area to determine whether it is necessary to adjust the operating parameters of the variable-frequency compressor; preset a pressure stability threshold E. If Pi stb,i > E or Pi stb,i < E, it is determined that it is necessary to adjust the operating parameters of the variable-frequency compressor, trigger a second optimization instruction; and calculate the second refrigerant flow rate Mi new,2,i of the ith temperature-controlled area for synchronous adjustment to ensure that each temperature-controlled area is in an optimal operating state.

[0010] Preferably, step S1 includes:

[0011] S11. Divide the internal space of the commercial freezer into multiple levels of temperature-controlled areas, and the temperature-controlled areas are divided according to the shelf levels inside the freezer;

[0012] S12. Set multiple monitoring points in each temperature-controlled area, install temperature sensors outside each temperature-controlled area, and real-time monitor the external environmental temperature Ti outsude,i ;

[0013] Monitor the temperature of the refrigerant during evaporation through the temperature sensor inside the evaporator to obtain the evaporation temperature Te of the i-th temperature control area. i ;

[0014] Install a temperature sensor in the condenser to monitor the condensation temperature Tc of the i-th temperature control area in real time. i ;

[0015] Monitor the operating frequency of the compressor through a Hall sensor or a rotational speed sensor to obtain the compressor frequency F of the i-th temperature control area. compressor,i ;

[0016] Detect the flow rate of the refrigerant in the pipeline through a flow sensor to obtain the refrigerant flow rate M of the i-th temperature control area. i ;

[0017] Monitor the evaporation pressure through the pressure sensor installed in the evaporator to obtain the evaporation pressure P of the i-th temperature control area. evap,i ;

[0018] Monitor the condensation pressure through the pressure sensor installed in the condenser to obtain the condensation pressure P of the i-th temperature control area. cond,i ;

[0019] S13. After cleaning, outlier processing, missing value filling, noise filtering, and data normalization of the data obtained in S12, establish an operating parameter set.

[0020] Preferably, S2 includes:

[0021] S21. In each temperature control area, monitor and record the obtained cargo load information and manual operation behavior information, and establish a regional load set. The regional load set includes: the regional cargo quantity N of the i-th temperature control area items,i , the average temperature T of the regional cargo avg,i , the average temperature T of the new goods new,i , the regional cabinet door switch frequency D door,i and the regional idle storage volume V area,i ;

[0022] S22. After cleaning and data normalization of the regional load set, calculate and obtain the load index F of the i-th temperature control area. zzs,i ;

[0023] S23. Preset a load threshold, and compare the load index F of the i-th temperature control area zzs,i with the load threshold to judge the load level of the temperature control area, including:

[0024]

[0025] Among them, Tthreshold1 and T threshold2 represent the first load threshold and the second load threshold set according to the design and usage environment of the refrigerator, and are dynamically adjusted according to actual needs.

[0026] Preferably, the load index F of the i-th temperature control area zzs,i is obtained as follows:

[0027] S221. First, calculate the influence of the cargo load on the temperature control area, and calculate and obtain the load influence index F of the i-th temperature control area items,i :

[0028]

[0029] In the formula, T set represents the ideal temperature set for the refrigerator; the meaning of this formula is: the load influence caused by the difference between the quantity and temperature of the goods and the set temperature; the larger the quantity and temperature of the goods, the higher the load of the refrigerator, and vice versa;

[0030] S222. Calculate the manual operation influence index F of the i-th temperature control area oper,i :

[0031] F oper,i =|D door,i ×(T new,i -T outsude,i )|;

[0032] In the formula, T outsude,i represents the external environment temperature of the i-th temperature control area, and D door,i represents the opening and closing frequency of the door;

[0033] The manual operation influence index F of the i-th temperature control area oper,i represents the load increment caused by manual operation. Frequent opening of the door or the addition of new goods at high temperature will increase the load of the refrigerator and thus affect its refrigeration efficiency;

[0034] S223. Combine the load influence index F of the i-th temperature control area obtained in S221 and S222 items,i and the manual operation influence index F of the i-th temperature control area oper,i , and calculate and obtain the load index F of the i-th temperature control area through the following formula zzs,i :

[0035] F zzs,i =F items,i +F oper,i .

[0036] Preferably, S2 further includes:

[0037] S24. When the first low load level is recognized, it indicates that the load in the i-th temperature control area is abnormal, which not only wastes the cold source but also causes unstable operating efficiency. Generate the first strategy: increase the current inventory by 10%-20% and increase the proportion of the cold insulation medium by 2%-3%. The cold insulation medium includes frozen bottles and cold insulation boards;

[0038] When the second medium load level is recognized, it indicates that the load in the i-th temperature control area is normal and the operating efficiency is qualified, so no optimization adjustment is required;

[0039] When the third high load level is recognized, it indicates that the load in the i-th temperature control area is abnormal. Generate the second strategy: reduce the current inventory by 10%-20% and increase the proportion of the cold insulation medium by 4%-6% to help alleviate the temperature fluctuation.

[0040] Preferably, S2 further includes:

[0041] S25. After implementing the first and second strategies, extract the evaporation pressure P evap,i 、condensation pressure P cond,i 、compressor frequency F compressor,i and refrigerant flow rate M i in the i-th temperature control area, and combine with the load index F zzs,i of the i-th temperature control area. After dimensionless processing, calculate and obtain the operating state coefficient L hxs,i of the i-th temperature control area through the following formula:

[0042]

[0043] S26. Preset the state efficiency threshold, and compare the operating state coefficient L hxs,i of the i-th temperature control area with the state efficiency threshold to determine whether the operating efficiency is qualified, including:

[0044] If the operating state coefficient L hxs,i of the i-th temperature control area is ≥ the state efficiency threshold, it indicates that the operating efficiency of the current temperature control area is qualified, and continue to operate;

[0045] If the operating state coefficient L hxs,i of the i-th temperature control area is < the state efficiency threshold, it indicates that the operating efficiency of the current temperature control area is unqualified, and send the first optimization instruction to the outside.

[0046] Preferably, S3 includes:

[0047] S31. After receiving the first optimization instruction, extract the evaporation temperature Te i 、condensation temperature Tc i and compressor frequency F compressor,i, after dimensionless processing, the refrigerant flow rate adjustment index R_adj is calculated by the following formula:

[0048]

[0049] In the formula, Te set represents the set target evaporation temperature, Tc set represents the set target condensation temperature, F nominal represents the nominal operating frequency of the compressor; k 1 , k 2 and k 3 represent weight values;

[0050] When R_adj > 0, it means that the refrigerant flow rate needs to be increased to enhance the refrigeration effect;

[0051] When R_adj = 0, it means that the refrigerant flow rate is qualified and does not need to be adjusted;

[0052] When R_adj < 0, it means that the refrigerant flow rate needs to be reduced to avoid excessive refrigeration;

[0053] S32. When it is recognized that R_adj > 0 or R_adj < 0, the new refrigerant flow rate M of the i-th temperature control area is calculated by the following formula new,i :

[0054] M new,i = M nominal ×(1 + α × R_adj);

[0055] In the formula, M nominal represents the standard refrigerant flow rate of the freezer temperature control area, and α is the refrigerant flow rate adjustment coefficient, which controls the flow rate adjustment range;

[0056] If R_adj is positive or R_adj is negative, the new refrigerant flow rate M of the i-th temperature control area is adjusted according to new,i this.

[0057] Preferably, S4 includes:

[0058] S41. Real-time monitor the evaporation pressure P of the i-th temperature control area evap,i and the condensation pressure P cond,i , and calculate and obtain the pressure stability index P of the i-th temperature control area through the following formula stb,i :

[0059]

[0060] Among them, ΔP evap,i represents the change increment of the evaporation pressure after adjustment according to the new refrigerant flow rate M of the i-th temperature control area new,i , ΔP cond,iThe basis for the i-th temperature control region according to the new refrigerant flow rate M new,i The incremental change in the condensation pressure after that, and Δt represents the time interval;

[0061] S42. Preset the pressure stability threshold E, and compare the pressure stability index P of the i-th temperature control region stb,i with the pressure stability threshold E. If P stb,i > E, it indicates that the pressure fluctuation in the temperature control region is abnormal and the pressure is too high;

[0062] If P stb,i < E, it indicates that the pressure fluctuation in the temperature control region is abnormal and the pressure is too low, resulting in waste of additional energy consumption;

[0063] When P std,i > E or P std,i < E, it is determined that the operating parameters of the variable-frequency compressor need to be adjusted, triggering the second optimization instruction; if P stb,i = E, it indicates that the pressure fluctuation in the temperature control region is normal, and it is determined that the operating parameters of the variable-frequency compressor do not need to be adjusted.

[0064] Preferably, S4 further includes:

[0065] S43. After receiving the second optimization instruction, calculate and obtain the new variable-frequency compressor frequency F of the i-th temperature control region through the following formula new,i :

[0066] F new,i = F compressor,i + K f × (E - P stb,i );

[0067] wherein, K f represents the frequency adjustment coefficient for smoothing the variable-frequency adjustment; the value range is set between 0.1 - 5.0;

[0068] When P stb,i > E or P stb,i < E, adjust the variable-frequency compressor according to the new variable-frequency compressor frequency F of the i-th temperature control region new,i .

[0069] Preferably, S4 further includes:

[0070] S44. After adjusting the variable-frequency compressor according to the new variable-frequency compressor frequency F of the i-th temperature control region new,i , it is necessary to synchronously adjust the new refrigerant flow rate M new,i to ensure that it matches the instruction requirements and prevent overcooling or overheating. Calculate and obtain the second refrigerant flow rate M of the i-th temperature control region through the following formula new,2,i :

[0071] Mnew,2,i = M new,i + α × (F new,i - F compressor,i );

[0072] Among them, α is the refrigerant flow rate adjustment coefficient, controlling the flow rate adjustment range; synchronously adjusting the second refrigerant flow rate M of the i-th temperature control area new,2,i to match the new frequency of the variable-frequency compressor F of the i-th temperature control area new,i for synchronous requirements.

[0073] The present invention provides an optimization method for controlling a variable-frequency compressor based on a commercial freezer. It has the following beneficial effects:

[0074] (1) For the optimization method for controlling a variable-frequency compressor based on a commercial freezer, by dividing the interior of the commercial freezer into multiple temperature control areas and setting monitoring points in each area, it can collect in real time key operating parameters including the evaporation temperature Te i of the i-th temperature control area, the condensation temperature Tc i , the compressor frequency F compressor,i , the refrigerant flow rate M i , the evaporation pressure P evap,i and the condensation pressure P cond,i etc. This regional management enables the freezer to precisely adjust according to the needs of different areas, thereby improving the overall temperature control accuracy and refrigeration effect.

[0075] (2) The present invention combines factors such as the load of goods and human operation behavior to construct the load index F of the i-th temperature control area zzs,i and compares it with a preset load level threshold to identify the load situation of each temperature control area. This method avoids the problem of uneven loads in different areas of traditional freezers and effectively reduces the overcooling or overheating phenomena in some areas.

[0076] (3) By adjusting the refrigerant flow rate to meet the refrigeration requirements of the freezer, the refrigerant flow rate adjustment index R_adj is used to achieve precise control of the temperature control area. This control method can be flexibly adjusted according to actual needs compared with the traditional fixed-frequency compressor adjustment, avoiding energy waste and improving the overall energy efficiency of the freezer.

[0077] (4) By real-time monitoring of the evaporation pressure P evap,i and the condensation pressure P cond,i , generating the pressure stability index P of the i-th temperature control area stb,i, to ensure that the compressor operates at its best. When it is found that the pressure fluctuation exceeds the set threshold, an optimization instruction is triggered to adjust the compressor operation parameters and synchronously regulate the refrigerant flow rate to ensure that the refrigeration effect in each temperature control area reaches the optimum. The present invention comprehensively considers multiple factors (such as regional load, ambient temperature, manual operation, etc.) to dynamically adjust and optimize the refrigeration strategy of the cold cabinet, not only improving the energy efficiency of the cold cabinet, but also enhancing its adaptability and stability under different environmental conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] Figure 1 It is a schematic diagram of the steps of a variable frequency compressor control optimization method based on a commercial cold cabinet according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0079] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0080] Embodiment 1

[0081] Please refer to Figure 1 , the present invention provides a variable frequency compressor control optimization method based on a commercial cold cabinet, including the following steps:

[0082] S1. The interior of the commercial cold cabinet is pre-divided into several temperature control areas according to levels, and monitoring points are set in each temperature control area to collect and obtain the operation parameters in each temperature control area, including the evaporation temperature Te of the i-th temperature control area i , the condensation temperature Tc i , the compressor frequency F compressor,i , the refrigerant flow rate M i , the evaporation pressure P evap,i and the condensation pressure P cond,i , and a set of operation parameters is established;

[0083] S2. The cargo load information and manual operation behavior information in the temperature control area are collected to establish a regional load set, and calculations are performed based on the regional load set to obtain the load index F of the i-th temperature control area zzs,i , and a load level threshold is preset to identify the operation load level of the i-th temperature control area from the current state and generate a corresponding first strategy or second strategy. After implementation, the operation state coefficient L of the i-th temperature control area is constructed hxs,i , and a state efficiency threshold is preset. If the operation state coefficient L of the i-th temperature control area hxs,i is lower than the state efficiency threshold, a first optimization instruction is triggered;

[0084] S3. After receiving the first optimization instruction, extract the evaporation temperature Te of the i-th temperature control zone in the set of operating parameters obtained in step S1 i , the condensation temperature Tc i and the compressor frequency F compressor,i , calculate the refrigerant flow rate adjustment index R_adj, and based on the refrigerant flow rate adjustment index R_adj, obtain the new refrigerant flow rate M of the adjusted i-th temperature control zone new,i , to match the refrigeration demand of the freezer

[0085] S4. Real-time monitor the evaporation pressure P of the i-th temperature control zone evap,i and the condensation pressure P cond,i , generate the pressure stability index P of the i-th temperature control zone stb,u , to determine whether it is necessary to adjust the operating parameters of the variable frequency compressor; preset the pressure stability threshold E, if P stb,i > E or P stb,i < E, then it is determined that it is necessary to adjust the operating parameters of the variable frequency compressor, trigger the second optimization instruction; and calculate the second refrigerant flow rate M of the i-th temperature control zone new,2,i for synchronous adjustment to ensure that each temperature control zone is in an optimal operating state

[0086] In this embodiment, by dividing the interior of the commercial freezer into multiple temperature control zones and setting monitoring points in each zone, it is possible to collect in real time the evaporation temperature Te including the i-th temperature control zone i , the condensation temperature Tc i , the compressor frequency F compressor,i , the refrigerant flow rate M i , the evaporation pressure P evap,i and the condensation pressure P cond,i and other key operating parameters. This regional management enables the freezer to perform precise adjustment according to the needs of different regions, thereby improving the overall temperature control accuracy and refrigeration effect

[0087] The present invention combines factors such as the load of goods and the behavior of manual operations to construct the load index F of the i-th temperature control zone zzs,i and compare it with the preset load level threshold, so as to identify the load situation of each temperature control zone. This method avoids the problem of uneven load in different zones in traditional freezers, and effectively reduces the overcooling or overheating phenomenon in some zones

[0088] By adjusting the refrigerant flow rate to meet the refrigeration demand of the freezer, the refrigerant flow rate adjustment index R_adj is used to achieve precise control of the temperature control zone. This control method can be adjusted flexibly according to actual needs compared with the traditional fixed-frequency compressor adjustment, avoiding energy waste and improving the overall energy efficiency of the freezer

[0089] By monitoring the evaporation pressure P in real time evap,i and the condensation pressure P cond,i , generate the pressure stability index Pi of the ith temperature control area stb,i to ensure that the compressor operates in the best state. When it is found that the pressure fluctuation exceeds the set threshold, an optimization instruction is triggered to adjust the compressor operation parameters, and the refrigerant flow rate is synchronously adjusted to ensure that the refrigeration effect of each temperature control area reaches the optimum. The present invention comprehensively considers multiple factors (such as regional load, ambient temperature, manual operation, etc.) to dynamically adjust and optimize the refrigeration strategy of the cold cabinet, which not only improves the energy efficiency of the cold cabinet, but also enhances its adaptability and stability under different environmental conditions.

[0090] Embodiment 2

[0091] This embodiment is an explanation and illustration based on Embodiment 1. Specifically, the S1 step includes:

[0092] S11. Divide the internal space of the commercial cold cabinet into multiple hierarchical temperature control areas, and the temperature control areas are divided according to the shelf levels inside the cold cabinet;

[0093] S12. Set multiple monitoring points in each temperature control area, install temperature sensors outside each temperature control area, and monitor the external environmental temperature Ti of the ith temperature control area in real time outsude,i ;

[0094] Monitor the temperature when the refrigerant evaporates through the temperature sensor inside the evaporator to obtain the evaporation temperature Te of the ith temperature control area i ;

[0095] Install a temperature sensor in the condenser to monitor the condensation temperature Tc of the ith temperature control area i ;

[0096] Monitor the operating frequency of the compressor through a Hall sensor or a rotational speed sensor to obtain the compressor frequency Fi of the ith temperature control area compressor,i ;

[0097] Detect the flow rate of the refrigerant in the pipeline through a flow sensor to obtain the refrigerant flow rate Mi of the ith temperature control area i ;

[0098] Monitor the evaporation pressure through the pressure sensor installed in the evaporator to obtain the evaporation pressure Pi of the ith temperature control area evap,i ;

[0099] Monitor the condensation pressure through the pressure sensor installed in the condenser to obtain the condensation pressure Pi of the ith temperature control area cond,i ;

[0100] S13. After cleaning, outlier processing, missing value filling, noise filtering and data normalization of the data obtained in S12, an operating parameter set is established.

[0101] In this embodiment, the interior of the commercial refrigerator is divided into multiple temperature control areas according to the shelf levels, which can manage the temperature of different areas inside the refrigerator more finely. This hierarchical management allows each area to be customized for temperature control according to actual load, cargo type and other conditions, avoiding the problem of uneven temperature in different areas in traditional refrigerators. Through detailed temperature control area division and real-time monitoring, the accuracy of temperature control inside the refrigerator can be greatly improved, temperature differences between areas can be avoided, and the optimal storage conditions for goods can be ensured. The optimized monitoring and adjustment method improves the energy efficiency of the refrigerator, especially under different loads, ambient temperatures and operating conditions, and can achieve higher refrigeration efficiency and energy utilization.

[0102] Example 3

[0103] This embodiment is the explanation and description in Embodiment 1. Specifically, S2 includes:

[0104] S21. In each temperature-controlled area, monitor and record the cargo load information and manual operation behavior information, and establish a regional load set. The regional load set includes: the number of regional cargo N in the i-th temperature-controlled area items,i , Regional cargo average temperature T avg,i 、The average temperature of new goods T new,i , Regional cabinet door opening and closing frequency D door,i and the free storage volume V area,i ;Accurately collect and record the load information of each temperature control area. These factors directly affect the temperature control effect and energy efficiency of the refrigerator. By obtaining this information, a comprehensive assessment of the workload of each area can be made.

[0105] The more goods there are, the greater the load pressure on the refrigerator, and the more difficult it is to control the temperature.

[0106] New goods are usually warmer, which increases the refrigeration load of the freezer and reduces energy efficiency.

[0107] Frequent opening and closing of cabinet doors will cause temperature fluctuations, increase the load on the refrigerator and affect energy efficiency.

[0108] Too much or too little free space may cause the refrigerator's refrigeration efficiency to be unstable and affect energy efficiency.

[0109] S22. After cleaning and normalizing the regional load set, calculate and obtain the load index F of the i-th temperature control area zzs，i ; Based on the data after cleaning, calculate the load index F of each temperature control area zzs，i, as the core basis for judging the operating status of each temperature control area in the refrigerator. The load index F zzs，i The calculation will help accurately identify the workload of each temperature control area in the refrigerator, thus providing a basis for subsequent optimization and adjustment.

[0110] S23. Preset a load threshold, and compare the load index F zzs,i of the i-th temperature control area with the load threshold to judge the load level of the temperature control area, including:

[0111]

[0112] wherein, T threshold1 and T threshold2 represent the first load threshold and the second load threshold set according to the design and use environment of the refrigerator, and are dynamically adjusted according to actual needs.

[0113] When the load index F zzs,i of the i-th temperature control area is lower than the first load threshold T threshold1 , it means that the load of the temperature control area in the refrigerator is insufficient, and there are problems of energy waste and low energy efficiency.

[0114] When the load index F zzs,i of the i-th temperature control area is higher than the second load threshold T threshold2 , when the load is too heavy, the burden on the temperature control area in the refrigerator is too large, which may cause temperature fluctuations and unstable operation.

[0115] The method for obtaining the load index F zzs,i of the i-th temperature control area is as follows:

[0116] S221. First, calculate the influence of the cargo load on the temperature control area, and calculate and obtain the load influence index F items,i of the i-th temperature control area:

[0117]

[0118] In the formula, T set represents the ideal temperature set for the refrigerator; the meaning of this formula is: the load influence caused by the difference between the quantity and temperature of the goods and the set temperature; the larger the quantity and temperature of the goods, the higher the load of the refrigerator, and vice versa;

[0119] S222. Calculate the manual operation influence index F oper,i of the i-th temperature control area:

[0120] F oper,i =|D door,i ×(T new,i -T outsude,i )|;

[0121] Where, T outsude,i represents the external ambient temperature of the i-th temperature control area, and D door,i represents the opening and closing frequency of the door;

[0122] The manual operation influence index F of the i-th temperature control area oper,i represents the load increment caused by manual operation. Frequent door opening or the addition of new high-temperature goods will increase the load of the refrigerator, thereby affecting its refrigeration efficiency;

[0123] S223. Combine the load influence index F of the i-th temperature control area obtained in S221 and S222 items,i and the manual operation influence index F of the i-th temperature control area oper,i , and calculate the load index F of the i-th temperature control area through the following formula zzs,i :

[0124] F zzs,i = F items,i + F oper,i .

[0125] S24. When the first low load level is identified, it indicates that the load of the i-th temperature control area is abnormal, which not only wastes the cold source but also causes unstable operation efficiency. Generate the first strategy: increase the current inventory by 10%-20% and increase the proportion of the cold insulation medium by 2%-3%. The cold insulation medium includes freezing bottles and cold insulation boards;

[0126] When the second medium load level is identified, it indicates that the load of the i-th temperature control area is normal and the operation efficiency is qualified, so no optimization adjustment is required; by increasing the inventory and the proportion of the cold insulation medium (such as freezing bottles and cold insulation boards), the load of the refrigerator is increased to avoid wasting the cold source and improve the operation efficiency.

[0127] When the third high load level is identified, it indicates that the load of the i-th temperature control area is abnormal. Generate the second strategy: reduce the current inventory by 10%-20% and increase the proportion of the cold insulation medium by 4%-6% to help alleviate the temperature fluctuation. By reducing the inventory and increasing the proportion of the cold insulation medium to alleviate the temperature fluctuation, ensure the stable operation of the refrigerator and avoid the energy efficiency loss caused by overloading.

[0128] S25. After implementing the first and second strategies, extract the evaporation pressure P evap,i , condensation pressure P cond,i , compressor frequency F compressor,i and refrigerant flow rate M i of the i-th temperature control area. Combine with the load index F zzs,i of the i-th temperature control area. After dimensionless processing, calculate the operation state coefficient L hxs,i of the i-th temperature control area through the following formula

[0129]

[0130] S26. Preset the state efficiency threshold, and compare the operation state coefficient L of the i-th temperature control area with the state efficiency threshold to determine whether the operation efficiency is qualified, including: hxs,i If the operation state coefficient L of the i-th temperature control area is greater than or equal to the state efficiency threshold, it means that the operation efficiency of the current temperature control area is qualified, and continue to operate;

[0131] If the operation state coefficient L of the i-th temperature control area hxs,i ≥ the state efficiency threshold, it means that the operation efficiency of the current temperature control area is qualified, and continue to operate;

[0132] If the operation state coefficient L of the i-th temperature control area hxs,i < the state efficiency threshold, it means that the operation efficiency of the current temperature control area is unqualified, and send the first optimization instruction to the outside.

[0133] In this embodiment, by comprehensively monitoring the cargo load, manual operations, and external environmental factors, the system can more accurately evaluate the load conditions of each temperature control area of the refrigerator, so as to provide corresponding optimization strategies under different load conditions. By identifying low-load and high-load situations, the system can dynamically adjust the ratio of the cargo stock to the cold insulation medium, thereby effectively improving the refrigeration efficiency of the refrigerator and reducing energy waste. According to the load index and the operation state coefficient, the operation efficiency of the refrigerator is evaluated in real time to ensure that the temperature control area is always in the best state, avoiding temperature fluctuations and equipment overload phenomena, and improving the product quality and the stability of the refrigerator. Through the intelligent optimization algorithm, the system can respond to load changes in real time, automatically execute the optimization instruction, reduce manual intervention, and improve the automation management level of the refrigerator.

[0134] Embodiment 4

[0135] This embodiment is an explanation and description based on Embodiment 1. Specifically, S3 includes:

[0136] S31. After receiving the first optimization instruction, extract the evaporation temperature Te, condensation temperature Tc, and compressor frequency F of the i-th temperature control area from the set of operation parameters obtained in step S1. After dimensionless processing, calculate the refrigerant flow rate adjustment index R_adj through the following formula: i 、condensation temperature Tc i and compressor frequency F compressor,i , after dimensionless processing, calculate the refrigerant flow rate adjustment index R_adj through the following formula:

[0137]

[0138] In the formula, Te set represents the set target evaporation temperature, Tc set represents the set target condensation temperature, F nominal represents the nominal operating frequency of the compressor; k 1 、k 2 and k 3Indicates the weight value;

[0139] When R_adj > 0, it indicates that the refrigerant flow rate needs to be increased to enhance the refrigeration effect;

[0140] When R_adj = 0, it indicates that the refrigerant flow rate is qualified and does not need to be adjusted;

[0141] When R_adj < 0, it indicates that the refrigerant flow rate needs to be decreased to avoid excessive refrigeration;

[0142] S32. When it is identified that R_adj > 0 or R_adj < 0, calculate the new refrigerant flow rate M of the i-th temperature control area through the following formula new,i :

[0143] M new,i = M nominal ×(1 + α×R_adj);

[0144] In the formula, M nominal represents the standard refrigerant flow rate of the freezer temperature control area, and α is the refrigerant flow rate adjustment coefficient, which controls the flow rate adjustment range;

[0145] If R_adj is positive or negative, adjust according to the new refrigerant flow rate M of the i-th temperature control area new,i for adjustment.

[0146] In this embodiment, by calculating the refrigerant flow rate adjustment index R_adj, the refrigerant flow rate can be accurately controlled to ensure the best refrigeration effect of the freezer under different loads and temperature control conditions. This not only improves the refrigeration efficiency of the freezer but also avoids energy waste caused by excessive refrigeration. According to the operating parameters of the freezer (such as evaporation temperature, condensation temperature, and compressor frequency), intelligently calculate and adjust the new refrigerant flow rate M of the i-th temperature control area new,i . This intelligent adjustment can not only respond to real-time load changes but also dynamically optimize operating parameters according to actual needs, improving the working efficiency of the freezer. By accurately controlling the refrigerant flow rate, avoiding excessive refrigeration or insufficient refrigeration, not only improves the operating efficiency of the freezer but also reduces the risk of equipment overload operation, thereby extending the service life of the equipment.

[0147] Embodiment 5

[0148] This embodiment is an explanation and illustration based on Embodiment 1. Specifically, S3 includes: S4 includes:

[0149] S41. Real-time monitor the evaporation pressure P of the i-th temperature control area evap,i and the condensation pressure P cond,i , and calculate and obtain the pressure stability index P of the i-th temperature control area through the following formula stb,i :

[0150]

[0151] Among them, ΔP evap,i represents the increment of the adjusted evaporation pressure change in the i-th temperature control area based on the new refrigerant flow rate M new,i ; ΔP cond,i represents the increment of the condensed pressure change in the i-th temperature control area after the new refrigerant flow rate M new,i ; Δt represents the time interval. According to the adjustment of the new refrigerant flow rate, the change amounts of the evaporation pressure and the condensation pressure are calculated. These change amounts reflect the influence of the refrigerant flow rate adjustment on the pressure in the temperature control area. This parameter is used to consider the time factor of the pressure change so that the calculation can reflect the dynamic response of the system during actual operation.

[0152] S42. Preset a pressure stability threshold E, and compare the pressure stability index P stb,i in the i-th temperature control area with the pressure stability threshold E. If P stb,i > E, it means that the pressure fluctuation in the temperature control area is abnormal and the pressure is too high;

[0153] If P stb,i < E, it means that the pressure fluctuation in the temperature control area is abnormal and the pressure is too low, resulting in waste of additional energy consumption;

[0154] When P stb,i > E or P stb,i < E, it is determined that the operating parameters of the variable-frequency compressor need to be adjusted, and the second optimization instruction is triggered; if P stb,i = E, it means that the pressure fluctuation in the temperature control area is normal, and it is determined that the operating parameters of the variable-frequency compressor do not need to be adjusted.

[0155] S43. After receiving the second optimization instruction, calculate and obtain the new variable-frequency compressor frequency F new,i in the i-th temperature control area through the following formula:

[0156] F new,i = F compressor,i + K f × (E - P stb,i );

[0157] Among them, K f represents the frequency adjustment coefficient, which is used to smooth the variable-frequency adjustment; the value range is set between 0.1 - 5.0;

[0158] When P stb,i > E or P stb,i < E, adjust the variable-frequency compressor according to the new variable-frequency compressor frequency F new,i in the i-th temperature control area.

[0159] S44. According to the new variable-frequency compressor frequency Fnew,i After adjusting the variable-frequency compressor, it is necessary to synchronously adjust the new refrigerant flow rate M new,i , ensure that it matches the command requirements, prevent overcooling or overheating, and obtain the second refrigerant flow rate M of the i-th temperature control area through the following formula calculation new,2,i :

[0160] M new,2,i = M new,i + α × (F new,i - F compressor,i );

[0161] Among them, α is the refrigerant flow rate adjustment coefficient, which controls the flow rate adjustment range; synchronously adjust the second refrigerant flow rate M of the i-th temperature control area new,2,i to match the new variable-frequency compressor frequency F of the i-th temperature control area new,i synchronization requirements.

[0162] In this embodiment, after adjusting the variable-frequency compressor frequency, it is necessary to synchronously adjust the refrigerant flow rate to ensure that the refrigerant flow rate matches the new frequency, prevent overcooling or overheating. The second refrigerant flow rate M of the i-th temperature control area new,2,i is synchronized with the adjustment range of the new variable-frequency compressor frequency F of the i-th temperature control area of the variable-frequency compressor, ensuring that the adjustment range of the refrigerant flow rate is consistent with the change of the compressor frequency. Through the synchronous adjustment of the variable-frequency compressor frequency and the refrigerant flow rate in this embodiment, it promotes the improvement of the energy efficiency of the freezer, the stability of the refrigeration effect, and the reduction of energy consumption waste. new,i

[0163] The setting of the size of the threshold is for the convenience of comparison. Regarding the size of the threshold, it depends on the amount of sample data and the number of base numbers set by those skilled in the art for each group of sample data; as long as it does not affect the proportional relationship between the parameter and the quantified value.

[0164] The above formulas are all obtained by collecting a large amount of data for software simulation and selecting a formula close to the true value. The coefficients in the formulas are set by those skilled in the art according to the actual situation. As described above, only the preferred specific implementation manner of the present invention is described, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.​

Claims

1. A variable frequency compressor control optimization method based on commercial refrigerators, characterized in that: The following steps are involved: S1. Divide the interior of the commercial refrigerator into several temperature control areas according to the level in advance, and set monitoring points in each temperature control area to collect and obtain the operating parameters in each temperature control area, including the evaporation temperature Te of the i-th temperature control area. i , condensation temperature Tc i , compressor frequency F compressor,i , Refrigerant flow rate M i , evaporation pressure P evap,i and condensation pressure P cond,i , establish a set of operating parameters; S2. Collect cargo load information and manual operation behavior information in the temperature control area, establish a regional load set, and calculate based on the regional load set to obtain the load index F of the i-th temperature control area. zzs,i , and preset the load level threshold to identify the operating load level of the i-th temperature control area from the current state, and generate the corresponding first strategy or second strategy. After implementation, the operating state coefficient L of the i-th temperature control area is constructed hxs,i , and preset the state efficiency threshold, if the operating state coefficient L of the i-th temperature control area hxs,i If it is lower than the state efficiency threshold, the first optimization instruction is triggered; S3, after receiving the first optimization instruction, extract the evaporation temperature Te of the i-th temperature control area in the operating parameter set obtained in step S1 i , condensation temperature Tc i and compressor frequency F compressor,i , calculate the refrigerant flow adjustment index R_adj, and based on the refrigerant flow adjustment index R_adj, obtain the new refrigerant flow M of the ith temperature control area to be adjusted new,i , to match the refrigeration needs of the freezer; S4. Real-time monitoring of the evaporation pressure P of the i-th temperature control area evap,i and condensation pressure P cond,i , generate the pressure stability index P of the i-th temperature control area stb,i , to determine whether it is necessary to adjust the operating parameters of the variable frequency compressor; Preset pressure stability threshold E, if P stb,i >E or P stb,i When <E, it is determined that the variable frequency compressor operating parameters need to be adjusted, triggering the second optimization instruction; and calculating the second refrigerant flow M of the i-th temperature control area new,2,i Perform synchronization adjustments.

2. The variable frequency compressor control optimization method based on commercial refrigerator according to claim 1 is characterized in that: The S1 step includes: S11, dividing the internal space of the commercial refrigerator into multiple levels of temperature control areas, and the temperature control areas are divided according to the shelf levels inside the refrigerator; S12, set up multiple monitoring points in each temperature control area, install temperature sensors outside each temperature control area, and monitor the external ambient temperature T of the i-th temperature control area in real time outsude,i ; The temperature of the refrigerant during evaporation is monitored by the temperature sensor inside the evaporator to obtain the evaporation temperature Te of the i-th temperature control area. i ; Install a temperature sensor in the condenser to monitor the condensing temperature Tc of the i-th temperature control area in real time. i ; Monitor the operating frequency of the compressor through the Hall sensor or speed sensor to obtain the compressor frequency F of the i-th temperature control area compressor,i ; The flow rate of the refrigerant in the pipeline is detected by the flow sensor to obtain the refrigerant flow rate M of the i-th temperature control area. i ; The evaporation pressure is monitored by the pressure sensor installed on the evaporator to obtain the evaporation pressure P of the i-th temperature control area. evap,i ; The condensing pressure is monitored by the pressure sensor installed on the condenser to obtain the condensing pressure P of the i-th temperature control area. cond,i ; S13. After cleaning, outlier processing, missing value filling, noise filtering and data normalization of the data obtained in S12, an operating parameter set is established.

3. The variable frequency compressor control optimization method based on commercial refrigerator according to claim 1 is characterized in that S2 include: S21. In each temperature-controlled area, monitor and record the cargo load information and manual operation behavior information, and establish a regional load set. The regional load set includes: the number of regional cargo N in the i-th temperature-controlled area items,i , Regional cargo average temperature T avg,i 、The average temperature of new goods T new,i , Regional cabinet door opening and closing frequency D door,i and the free storage volume V area,i ; S22. After cleaning and normalizing the regional load set, calculate and obtain the load index F of the i-th temperature control area zzs,i ; S23, preset the load threshold, and set the load index F of the i-th temperature control area zzs,i Compare with the load threshold to determine the load level of the temperature control area, including: Among them, T threshold1 and T threshold2 It means that the first load threshold and the second load threshold are set according to the design and use environment of the refrigerator, and are dynamically adjusted according to actual needs.

4. The variable frequency compressor control optimization method based on commercial refrigerator according to claim 3 is characterized in that: The load index F of the i-th temperature control area zzs,i The way to obtain is: S221. First, calculate the impact of the cargo load on the temperature control area, and calculate and obtain the load impact index F of the i-th temperature control area. items,i : Where, T set Indicates the ideal temperature for the freezer. This formula means: the load effect caused by the difference between the quantity of goods and the temperature of the goods and the set temperature. The greater the quantity and temperature of the goods, the higher the freezer load, and vice versa. S222. Calculate the manual operation influence index F of the ith temperature control area oper,i : F oper,i =|D door,i ×(T new,i -T outsude,i )|; Where, T outsude,i represents the external ambient temperature of the ith temperature control area, D door,i Indicates the switching frequency of the gate; The influence index F of manual operation in the i-th temperature control area oper,i Indicates that the load increment caused by manual operation, frequent door opening or the addition of new high-temperature goods will increase the load of the freezer, thus affecting its refrigeration efficiency; S223: Combine the load influence index F of the i-th temperature control area obtained in S221 and S222 items,i and the manual operation influence index F of the i-th temperature control area oper,i , calculate the load index F of the i-th temperature control area using the following formula: zzs,i : F zzs,i =F items,i +F oper,i 。 5. The variable frequency compressor control optimization method based on commercial refrigerator according to claim 3 is characterized in that: S2 also includes: S24, when the first low load level is identified, it indicates that the load of the i-th temperature control area is abnormal, which not only wastes the cold source but also leads to unstable operation efficiency, and generates a first strategy: increasing the current cargo inventory by 10%-20% and increasing the proportion of cold-keeping medium by 2%-3%, wherein the cold-keeping medium includes frozen bottles and cold-keeping plates; When the second load level is identified, it means that the load of the i-th temperature control area is normal, the operating efficiency is qualified, and no optimization adjustment is required; When the third highest load level is identified, indicating that the load of the i-th temperature-controlled area is abnormal, a second strategy is generated to reduce the current cargo inventory by 10%-20% and increase the proportion of cold-keeping medium by 4%-6% to help alleviate temperature fluctuations.

6. The variable frequency compressor control optimization method based on commercial refrigerator according to claim 3 is characterized in that: S2 also includes: S25. After the first strategy and the second strategy are implemented, extract the evaporation pressure P of the i-th temperature control area. evap,i , condensation pressure P cond,i , compressor frequency F compressor,i And refrigerant flow M i , combined with the load index F of the i-th temperature control area zzs,i After dimensionless processing, the operating state coefficient L of the i-th temperature control area is calculated by the following formula: hxs,i : S26, preset the state efficiency threshold, and set the operating state coefficient L of the i-th temperature control area hxs,i Compare with the state efficiency threshold to determine whether the operating efficiency is qualified, including: If the operating state coefficient L of the i-th temperature control area hxs,i ≥ the state efficiency threshold, it means that the current temperature control area has qualified operating efficiency and continues to operate; If the operating state coefficient L of the i-th temperature control area hxs,i < state efficiency threshold, it means that the operating efficiency of the current temperature control area is unqualified, and the first optimization instruction is sent to the outside.

7. The variable frequency compressor control optimization method based on commercial refrigerator according to claim 1 is characterized in that S3 include: S31, after receiving the first optimization instruction, extract the evaporation temperature Te of the i-th temperature control area in the operating parameter set obtained in step S1 i , condensation temperature Tc i and compressor frequency F compressor,i , after dimensionless processing, the refrigerant flow regulation index R_adj is calculated by the following formula: In the formula, Te set Indicates the set target evaporation temperature, Tc set Indicates the set target condensing temperature, F nominal represents the nominal operating frequency of the compressor; k1, k2 and k3 represent weight values; When R_adj>0, it means that the refrigerant flow rate needs to be increased to enhance the cooling effect; When R_adj=0, it means the refrigerant flow rate is qualified and no adjustment is required; When R_adj<0, it means that the refrigerant flow needs to be reduced to avoid over-cooling; S32. When it is identified that R_adj>0 or R_adj<0, the new refrigerant flow M of the i-th temperature control area is calculated by the following formula new,i : M new,i =M nominal ×(1+α×R_adj); Where M nominal It represents the standard refrigerant flow rate in the temperature control area of ​​the refrigerator, α is the refrigerant flow rate adjustment coefficient, and controls the flow rate adjustment range; If R_adj is positive or negative, the new refrigerant flow M of the i-th temperature control area new,i Make adjustments.

8. The variable frequency compressor control optimization method based on commercial refrigerator according to claim 1 is characterized in that S4 include: S41, real-time monitoring of the evaporation pressure P of the i-th temperature control area evap,i and condensation pressure P cond,i The pressure stability index P of the i-th temperature control area is calculated by the following formula: stb,i : Among them, ΔP evap,i Indicates the new refrigerant flow M of the i-th temperature control area new,i Adjusted evaporation pressure change increment, ΔP cond,i Indicates the new refrigerant flow M of the i-th temperature control area new,i The increment of condensing pressure change after the condensing pressure is Δt, which represents the time interval; S42, preset a pressure stability threshold E, and calculate the pressure stability index P of the i-th temperature control area. stb,i Compared with the pressure stability threshold E, if P stb,i >E, it means that the pressure fluctuation in the temperature control area is abnormal and the pressure is too high; If P stb,i <E, it means that the pressure fluctuation in the temperature control area is abnormal and the pressure is too low, resulting in extra energy waste; When P stb,i >E or P stb,i <E, it is determined that the variable frequency compressor operating parameters need to be adjusted, triggering the second optimization instruction; if P stb,i =E, it means that the pressure fluctuation in the temperature control area is normal, and it is judged that there is no need to adjust the operating parameters of the variable frequency compressor.

9. The variable frequency compressor control optimization method based on commercial refrigerator according to claim 8, characterized in that: S4 also includes: S43, after receiving the second optimization instruction, the new variable frequency compressor frequency F of the i-th temperature control area is calculated by the following formula: new,i : F new,i =F compressor,i +K f ×(E-P stb,i ); Among them, K f Indicates the frequency adjustment coefficient, which is used for smooth frequency conversion adjustment; the value range is set between 0.1-5.0; When P stb,i >E or P stb,i When <E, the frequency F of the new variable frequency compressor in the i-th temperature control area new,i Adjust the variable frequency compressor.

10. A variable frequency compressor control optimization method based on a commercial refrigerator according to claim 9, characterized in that: S4 also includes: S44, according to the new variable frequency compressor frequency F of the i-th temperature control area new,i After adjusting the variable frequency compressor, the new refrigerant flow M needs to be adjusted synchronously new,i , to ensure matching instruction requirements and prevent overcooling or overheating, the second refrigerant flow M of the i-th temperature control area is calculated by the following formula new,2,i : M new,2,i =M new,i +α×(F new,i -F compressor,i ); Among them, α is the refrigerant flow adjustment coefficient, which controls the flow adjustment range; synchronously adjusts the second refrigerant flow M of the i-th temperature control area new,2,i To match the new variable frequency compressor frequency F of the i-th temperature control area new,i synchronization requirements.

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