A variable frequency compressor control optimization method based on a commercial refrigerator

Abstract

The application discloses a kind of based on commercial refrigerator's variable frequency compressor control optimization method, it is related to refrigeration optimization control technical field, the commercial refrigerator is divided into multiple independent temperature control regions, and monitoring point is deployed in each region, realizes fine temperature control and load management;Based on the load index F of the i temperature control region of goods load and artificial operation behavior zzs,i Calculation method is used to identify the load condition of each temperature control region, and the dynamic refrigeration demand of the refrigerator is met by adjusting the refrigerant flow, and the refrigerant flow adjustment index R_adj is used to realize accurate control of each temperature control region, compared with the traditional fixed-frequency compressor adjustment, the refrigeration capacity can be flexibly adjusted according to real-time demand. The pressure stability index is used to monitor the evaporation pressure and condensation pressure, and automatically trigger the optimization instruction to adjust the operating parameters of the variable frequency compressor and simultaneously optimize the refrigerant flow to ensure the balance of refrigeration in each region.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of refrigeration optimization control, in particular to a variable frequency compressor control optimization method based on a commercial refrigerator. BACKGROUND

[0002] With the continuous development of commercial refrigerator technology and the increasing demand for application, traditional commercial refrigerators are facing more and more challenges in terms of energy efficiency, operation efficiency, temperature control accuracy and environmental adaptability. Traditional refrigerators usually use a single compressor and refrigeration system, and do not fully consider the temperature fluctuations and load differences in different areas inside the refrigerator, resulting in low overall energy efficiency and suboptimal refrigeration effect. In addition, the refrigeration efficiency of the refrigerator is usually affected by external environmental temperature, storage requirements of goods and manual operation, etc. Changes in these factors make it difficult for the refrigerator system to achieve efficient and stable temperature control management, further affecting the operation stability and product quality of the refrigerator.

[0003] To solve these problems, variable frequency compressors, as a high-efficiency control device, have been widely used in commercial refrigerators. Variable frequency compressors can precisely adjust the flow rate of refrigerant and the temperature of the temperature control area by adjusting the speed of the compressor, avoiding the energy waste of traditional fixed-frequency compressors when the load fluctuates. However, although the introduction of variable frequency compressors has improved the energy efficiency of the refrigerator to some extent, traditional commercial refrigerators still have the following problems: first, the load distribution in the temperature control area is uneven, resulting in overcooling or overheating in some areas of the refrigerator; second, there is a lack of comprehensive optimization management of multiple factors (such as goods load, manual operation behavior, external environment, etc.), which cannot effectively achieve temperature control balance between areas; third, the frequency adjustment of the compressor and the refrigerant flow adjustment are often difficult to optimize collaboratively, limiting the improvement of refrigeration efficiency. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a variable frequency compressor control optimization method based on a commercial refrigerator to solve the problems mentioned in the background.

[0005] To achieve the above purpose, the present application realizes the following technical scheme: a variable frequency compressor control optimization method based on a commercial refrigerator, comprising the following steps:

[0006] S1, pre-dividing the interior of the commercial refrigerator into several temperature control areas according to levels, and setting monitoring points in each temperature control area to collect and obtain the operating parameters in each temperature control area, including the evaporating temperature Te i , the condensing temperature Tc i , the compressor frequency F compressor,i , the refrigerant flow M i , the evaporating pressure P evap,iand condensing pressure P cond,i , a set of operating parameters is established;

[0007] S2, collect the cargo load information and manual operation behavior information in the temperature control area, establish a regional load set, and calculate the load index F of the i-th temperature control area according to the regional load set; zzs,i , and preset a load level threshold to identify the operating load level of the i-th temperature control area from the current state, and generate a corresponding first strategy or second strategy, and after implementation, the operating state coefficient L of the i-th temperature control area is constructed; hxs,i , and preset a state efficiency threshold, if the operating state coefficient L of the i-th temperature control area is lower than the state efficiency threshold, the first optimization instruction is triggered; hxs,i

[0008] S3, after receiving the first optimization instruction, the evaporation temperature Te of the i-th temperature control area in the set of operating parameters obtained in step S1 is extracted; i , the condensing temperature Tc i and the compressor frequency F compressor,i , the refrigerant flow adjustment index R_adj is calculated, and based on the refrigerant flow adjustment index R_adj, the adjusted new refrigerant flow M of the i-th temperature control area is obtained; new,i to match the refrigeration demand of the refrigerator;

[0009] S4, the evaporation pressure P evap,i and the condensing pressure P cond,i of the i-th temperature control area are monitored in real time, the pressure stability index P of the i-th temperature control area is generated; stb,i to determine whether the variable frequency compressor operating parameters need to be adjusted; preset a pressure stability threshold E, if P stb,i >E or P stb,i <E, it is judged that the variable frequency compressor operating parameters need to be adjusted, the second optimization instruction is triggered; and the second refrigerant flow M of the i-th temperature control area is calculated; new,2,i synchronized adjustment is performed to ensure that each temperature control area is in an optimal operating state.

[0010] Preferably, step S1 comprises:

[0011] S11, the internal space of the commercial refrigerator is divided into multiple hierarchical temperature control areas, and the temperature control areas are divided according to the shelf levels inside the refrigerator;

[0012] S12, a plurality of monitoring points are arranged in each temperature control area, and a temperature sensor is installed outside each temperature control area to monitor the external environment temperature T of the i-th temperature control area in real time; outsude,i

[0013] ​​The temperature of the refrigerant during evaporation is monitored by a temperature sensor inside the evaporator to obtain the evaporation temperature Te of the ith temperature control area i ;

[0014] A temperature sensor is installed in the condenser to monitor the condensation temperature Tc of the ith temperature control area in real time i ;

[0015] The operating frequency of the compressor is monitored by a Hall sensor or a rotational speed sensor to obtain the compressor frequency F of the ith temperature control area compressor,i ;

[0016] The flow rate of the refrigerant in the pipeline is detected by a flow sensor to obtain the refrigerant flow rate M of the ith temperature control area i ;

[0017] The evaporation pressure is monitored by a pressure sensor installed in the evaporator to obtain the evaporation pressure P of the ith temperature control area evap,i ;

[0018] The condensation pressure is monitored by a pressure sensor installed in the condenser to obtain the condensation pressure P of the ith 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, an operating parameter set is established.

[0020] Preferably, S2 comprises:

[0021] S21, in each temperature control area, the cargo load information and manual operation behavior information are monitored and recorded to establish a regional load set, and the regional load set comprises: the regional cargo quantity N of the ith temperature control area items,i , the regional cargo average temperature T avg,i , the average temperature T of new goods new,i , the regional cabinet door opening and closing 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, the load index F of the ith temperature control area is calculated zzs,i ;

[0023] S23, a load threshold is preset, and the load index F of the ith temperature control area zzs,i is compared with the load threshold to determine the load level of the temperature control area, which comprises:

[0024]

[0025] Wherein, Tthreshold1 and T threshold2 represent the first load threshold and the second load threshold set according to the design of the refrigerator and the use environment, which are dynamically adjusted according to the actual demand.

[0026] Preferably, the load index F zzs,i of the ith temperature control area is obtained in the following way:

[0027] S221, first calculate the impact of the cargo load on the temperature control area, and calculate the load impact index F items,i of the ith temperature control area:

[0028]

[0029] In the formula, T set represents the set ideal temperature of the refrigerator; the meaning of this formula is that the load impact caused by the difference between the cargo quantity and cargo temperature and the set temperature; the greater the cargo quantity and temperature, the higher the load of the refrigerator, and vice versa;

[0030] S222, calculate the manual operation impact index F oper,i of the ith temperature control area:

[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 ith temperature control area, and D door,i represents the door opening frequency;

[0033] The manual operation impact index F oper,i of the ith temperature control area indicates that the load is increased due to manual operation, and frequent door opening or the addition of high-temperature new goods will increase the load of the refrigerator, thereby affecting the refrigeration efficiency;

[0034] S223, combine the load impact index F items,i of the ith temperature control area obtained in S221 and the manual operation impact index F oper,i of the ith temperature control area, and calculate the load index F zzs,i of the ith temperature control area by the following formula:

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

[0036] Preferably, S2 further comprises:

[0037] S24, when the first low load level is identified, indicating that the load of the i-th temperature control area is abnormal, not only wasting the cold source, but also leading to unstable operation efficiency, generating a first strategy: increasing the current inventory of goods by 10%-20%, and increasing the proportion of cold medium by 2%-3%, the cold medium including frozen bottles and cold plates;

[0038] 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 there is no need for optimization adjustment;

[0039] When the third high load level is identified, it indicates that the load of the i-th temperature control area is abnormal, and a second strategy is generated to reduce the current inventory of goods by 10%-20% and increase the proportion of cold medium by 4%-6% to help alleviate temperature fluctuations.

[0040] Preferably, S2 further comprises:

[0041] S25, after the implementation of the first strategy and the second strategy, the evaporation pressure P evap,i , condensation pressure P cond,i , compressor frequency F compressor,i and refrigerant flow M i of the i-th temperature control area are extracted, combined with the load index F zzs,i of the i-th temperature control area, after dimensionless processing, the operation state coefficient L hxs,i of the i-th temperature control area is calculated according to the following formula:

[0042]

[0043] S26, a state efficiency threshold is preset, and the operation state coefficient L hxs,i of the i-th temperature control area is compared with the state efficiency threshold to determine whether the operation efficiency is qualified, including:

[0044] If the operation state coefficient L hxs,i of the i-th temperature control area is greater than or equal to the state efficiency threshold, it indicates that the current temperature control area has qualified operation efficiency, and continues to run;

[0045] If the operation state coefficient L hxs,i of the i-th temperature control area is less than the state efficiency threshold, it indicates that the current temperature control area has unqualified operation efficiency, and sends a first optimization instruction to the outside.

[0046] Preferably, S3 comprises:

[0047] S31, after receiving the first optimization instruction, the evaporation temperature Te i , condensation temperature Tc i and compressor frequency F compressor,iAfter non-dimensional processing, the refrigerant flow adjustment index R adj is calculated by the following formula:

[0048]

[0049] where 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; k1, k2 and k3 represent weight values;

[0050] When R adj > 0, it indicates that the refrigerant flow needs to be increased to enhance the refrigeration effect;

[0051] When R adj = 0, it indicates that the refrigerant flow is qualified and does not need to be adjusted;

[0052] When R adj < 0, it indicates that the refrigerant flow needs to be reduced to avoid excessive refrigeration;

[0053] S32, when R adj > 0 or R adj < 0 is identified, the new refrigerant flow M new,i of the i-th temperature control area is calculated by the following formula:

[0054] M new,i = M nominal × (1 + a × R adj);

[0055] where M nominal represents the standard refrigerant flow of the refrigerator temperature control area, a is the refrigerant flow adjustment coefficient, and the flow adjustment range is controlled;

[0056] If R adj is positive or R adj is negative, the new refrigerant flow M new,i of the i-th temperature control area is adjusted.

[0057] Preferably, S4 comprises:

[0058] S41, the evaporation pressure P evap,i and the condensation pressure P cond,i of the i-th temperature control area are monitored in real time, and the pressure stability index P stb,i of the i-th temperature control area is calculated by the following formula:

[0059]

[0060] where ΔP evap,i represents the evaporation pressure change increment of the i-th temperature control area after adjustment according to the new refrigerant flow M new,i , and ΔP cond,i represents the condensation pressure change increment of the i-th temperature control area after adjustment according to the new refrigerant flow M new,iThe increment of condensing pressure change after Δt represents the time interval;

[0061] S42: Preset the 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;

[0062] 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;

[0063] When P std,i >E or P std,i When P<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 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.

[0064] Preferably, S4 further includes:

[0065] S43, after receiving the second optimization instruction, calculate the new variable frequency compressor frequency F of the i-th temperature control area by the following formula: new,i :

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

[0067] 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;

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

[0069] Preferably, S4 further includes:

[0070] 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 that the instruction requirements are matched and to prevent overcooling or overheating, the second refrigerant flow M of the i-th temperature control area is calculated using the following formula: new,2,i :

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

[0072] Wherein, α is the refrigerant flow adjustment coefficient, controlling the flow adjustment range; synchronously adjust the second refrigerant flow M new,2,i of the i-th temperature control area to match the new frequency F new,i of the variable frequency compressor of the i-th temperature control area.

[0073] The present application provides a variable frequency compressor control optimization method based on commercial refrigerators. It has the following beneficial effects:

[0074] (1) The variable frequency compressor control optimization method based on commercial refrigerators divides the interior of the commercial refrigerator into multiple temperature control areas and sets monitoring points in each area, which can collect key operating parameters such as the evaporation temperature Te i , condensation temperature Tc i , compressor frequency F compressor,i , refrigerant flow M i , evaporation pressure P evap,i and condensation pressure P cond,i of the i-th temperature control area in real time. This regional management allows the refrigerator to accurately adjust to the needs of different areas, improving overall temperature control accuracy and refrigeration effect.

[0075] (2) The present application combines factors such as cargo load and manual operation behavior to construct the load index F zzs,i of the i-th temperature control area and compare it with the preset load level threshold, thereby identifying the load situation of each temperature control area. This method avoids the problem of uneven load in different areas of traditional refrigerators, effectively reducing the phenomenon of overcooling or overheating in some areas.

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

[0077] (4) By monitoring the evaporation pressure P evap,i and condensation pressure P cond,i in real time, the pressure stability index P stb,i, to ensure that the operation of the compressor is in the best state. When it is found that the pressure fluctuation exceeds the set threshold, the optimization instruction is triggered to adjust the compressor operating parameters, and the refrigerant flow is adjusted synchronously to ensure that the refrigeration effect of each temperature control area reaches the optimum. The present application comprehensively considers multiple factors (such as regional load, environmental temperature, manual operation, etc.) to dynamically adjust and optimize the refrigeration strategy of the refrigerator, which not only improves the energy efficiency of the refrigerator, but also enhances its adaptability and stability under different environmental conditions. BRIEF DESCRIPTION OF DRAWINGS

[0078] Figure 1 For the steps of the present application, a variable frequency compressor control optimization method based on a commercial refrigerator is shown in the figure. DETAILED DESCRIPTION

[0079] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0080] Embodiment 1

[0081] Please refer to Figure 1 , the present application provides a variable frequency compressor control optimization method based on a commercial refrigerator, comprising the following steps:

[0082] S1, the inside of the commercial refrigerator is divided into several temperature control areas according to the level, and monitoring points are set in each temperature control area to collect and obtain the operating parameters in each temperature control area, including the evaporation temperature Te i , the condensation temperature Tc i , the compressor frequency F compressor,i , the refrigerant flow M i , the evaporation pressure P evap,i and the condensation pressure P cond,i , and the operating parameter set is established;

[0083] S2, collect the goods load information and manual operation behavior information in the temperature control area, establish the regional load set, calculate the load index F zzs,i of the i-th temperature control area according to the regional load set, and preset the load level threshold to identify the running 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 running state coefficient L hxs,i of the i-th temperature control area is constructed, and the state efficiency threshold is preset. If the running state coefficient L hxs,i of the i-th temperature control area is lower than the state efficiency threshold, the first optimization instruction is triggered;

[0084] S3, after receiving the first optimization instruction, extracting the evaporation temperature Te of the i-th temperature control region in the set of operating parameters obtained in step S1 i , the condensation temperature Tc i , and the compressor frequency F compressor,i , calculating the refrigerant flow adjustment index R_adj, and based on the refrigerant flow adjustment index R_adj, obtaining the adjusted new refrigerant flow M of the i-th temperature control region new,i to match the refrigeration demand of the refrigerator;

[0085] S4, real-time monitoring the evaporation pressure P evap,i and the condensation pressure P cond,i of the i-th temperature control region, generating the pressure stability index P stb,u of the i-th temperature control region to determine whether the variable frequency compressor operating parameters need to be adjusted; a preset pressure stability threshold E, if P stb,i >E or P stb,i <E, it is judged that the variable frequency compressor operating parameters need to be adjusted, triggering the second optimization instruction; and calculating the second refrigerant flow M new,2,i of the i-th temperature control region for synchronous adjustment to ensure that each temperature control region is in an optimal operating state.

[0086] In this embodiment, by dividing the interior of the commercial refrigerator into multiple temperature control regions and setting monitoring points in each region, key operating parameters including the evaporation temperature Te i , the condensation temperature Tc i , the compressor frequency F compressor,i , the refrigerant flow M i , the evaporation pressure P evap,i and the condensation pressure P cond,i of the i-th temperature control region can be collected in real time. This regional management allows the refrigerator to accurately adjust to the needs of different regions, thereby improving the overall temperature control accuracy and refrigeration effect.

[0087] The present application combines factors such as cargo load and manual operation behavior to construct the load index F zzs,i of the i-th temperature control region and compare it with the preset load level threshold to identify the load situation of each temperature control region. This method avoids the problem of uneven load in different regions of traditional refrigerators, effectively reducing the phenomenon of overcooling or overheating in some regions.

[0088] By adjusting the refrigerant flow to meet the refrigeration demand of the refrigerator, the refrigerant flow adjustment index R_adj is used to achieve accurate control of the temperature control region. Compared with the traditional fixed-frequency compressor adjustment, this control method can be flexibly adjusted according to the actual demand, avoiding energy waste and improving the overall energy efficiency of the refrigerator.

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

[0090] Embodiment 2

[0091] This embodiment is an explanation and description in embodiment 1, specifically, the S1 step includes:

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

[0093] S12, setting multiple monitoring points in each temperature control area, and installing temperature sensors outside each temperature control area to monitor the external environmental temperature T outsude,i of the i-th temperature control area in real time;

[0094] Monitoring the temperature of the refrigerant during evaporation through the temperature sensor inside the evaporator to obtain the evaporation temperature Te i of the i-th temperature control area;

[0095] Installing a temperature sensor in the condenser to monitor the condensation temperature Tc i of the i-th temperature control area in real time;

[0096] Monitoring the operating frequency of the compressor through the Hall sensor or the speed sensor to obtain the compressor frequency F compressor,i of the i-th temperature control area;

[0097] Detecting the flow of refrigerant in the pipeline through the flow sensor to obtain the refrigerant flow M i of the i-th temperature control area;

[0098] Monitoring the evaporation pressure through the pressure sensor installed in the evaporator to obtain the evaporation pressure P evap,i of the i-th temperature control area;

[0099] Monitoring the condensation pressure through the pressure sensor installed in the condenser to obtain the condensation pressure P cond,i of the i-th temperature control area;

[0100] S13, after cleaning, outlier processing, missing value filling, noise filtering and data normalization of the data obtained in S12, a set of operating parameters 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 more finely manage the temperature of different areas inside the refrigerator. This hierarchical management enables each area to be customized for temperature control adjustment according to actual load, goods type and other conditions, avoiding the problem of uneven temperature in different areas of traditional refrigerators. Through detailed temperature control area division and real-time monitoring, the accuracy of temperature control inside the refrigerator can be greatly improved, avoiding temperature differences between areas and ensuring optimal storage conditions for goods. The optimized monitoring and adjustment method improves the energy efficiency of the refrigerator, especially under different loads, environmental temperatures and operating conditions, achieving higher refrigeration efficiency and energy utilization.

[0102] Embodiment 3

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

[0104] S21, in each temperature control area, monitor and record the obtained goods load information and manual operation behavior information, establish a regional load set, the regional load set includes: the number of regional goods N items,i , the average temperature T avg,i of the new goods new,i , the frequency D of the opening and closing of the regional cabinet door door,i , and the idle storage volume V area,i of the region; 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, the working load of each area can be comprehensively evaluated.

[0105] The more the number of goods, the greater the load pressure on the refrigerator, and the temperature control difficulty also increases.

[0106] The temperature of new goods is usually high, which will increase the refrigeration load of the refrigerator, resulting in reduced energy efficiency.

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

[0108] Too much or too little idle space can cause the refrigeration efficiency of the refrigerator to be unstable, affecting energy efficiency.

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

[0110] 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:

[0111]

[0112] Among them, T threshold1 and T threshold2 Indicates the first load threshold and the second load threshold set according to the design and usage environment of the refrigerator, and dynamically adjusted according to actual needs.

[0113] The load index F of the i-th temperature control area zzs,i Below the first load threshold T threshold1 When the temperature is too low, it means that the temperature control area in the refrigerator is underloaded, resulting in energy waste and low energy efficiency.

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

[0115] The load index F of the i-th temperature control area zzs,i The way to obtain is:

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

[0117]

[0118] Where, T set Indicates the ideal temperature setting for the freezer. This formula reflects the load impact caused by the quantity of goods and the difference between the temperature of the goods and the set temperature. The greater the quantity of goods and the temperature, the higher the freezer load, and vice versa.

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

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

[0121] In the formula, T outsude,i represents the external environment temperature of the i-th temperature control area, D door,i represents the on-off frequency of the door;

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

[0123] S223, in combination with the load influence index F items,i of the i-th temperature control area obtained in S221 and S222 oper,i , the load index F zzs,i of the i-th temperature control area is calculated by the following formula:

[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, not only wasting the cold source, but also causing unstable operation efficiency, and generates the first strategy: increasing the current inventory of goods by 10%-20% and increasing the proportion of cold storage medium by 2%-3%, the cold storage medium including frozen bottles and cold storage plates;

[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, and there is no need for optimization adjustment; by increasing the inventory of goods and the proportion of cold storage medium (such as frozen bottles and cold storage plates), the load of the refrigerator is improved, the cold source is avoided to be wasted, and the operation efficiency is improved.

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

[0128] S25, after the implementation of the first strategy and the second strategy, the evaporation pressure P evap,i , the condensation pressure P cond,i , the compressor frequency F compressor,i and the refrigerant flow M i of the i-th temperature control area are extracted, in combination with the load index F zzs,i of the i-th temperature control area, after dimensionless processing, the operation state coefficient L hxs,i of the i-th temperature control area is calculated by the following formula:

[0129]

[0130] S26, preset state efficiency threshold, and the running state coefficient L of the i-th temperature control area is compared with the state efficiency threshold to determine whether the running efficiency is qualified, including: hxs,i

[0131] If the running state coefficient L of the i-th temperature control area is greater than or equal to the state efficiency threshold, it indicates that the current temperature control area running efficiency is qualified, and continues to run. hxs,i

[0132] If the running state coefficient L of the i-th temperature control area is less than the state efficiency threshold, it indicates that the current temperature control area running efficiency is unqualified, and a first optimization instruction is sent to the outside. hxs,i

[0133] In this embodiment, by comprehensively monitoring the load of goods, manual operation and external environmental factors, the system can more accurately evaluate the load condition 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 conditions, the system can dynamically adjust the proportion of goods inventory and cold preservation medium, thereby effectively improving the refrigeration efficiency of the refrigerator and reducing energy waste. According to the load index and the running state coefficient, the running efficiency of the refrigerator is evaluated in real time to ensure that the temperature control area is always in the best state, avoid temperature fluctuations and equipment overload, and improve product quality and refrigerator stability. Through intelligent optimization algorithm, the system can respond to load changes in real time, automatically execute optimization instructions, reduce manual intervention, and improve the automation management level of the refrigerator.

[0134] Embodiment 4

[0135] This embodiment is an explanation and description in embodiment 1, specifically, S3 includes:

[0136] S31, when receiving the first optimization instruction, the evaporation temperature Te of the i-th temperature control area in the running parameter set obtained in S1 is extracted i , the condensation temperature Tc i and the compressor frequency F compressor,i , after dimensionless processing, the refrigerant flow adjustment index R_adj is calculated by 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 working frequency of the compressor; k1, k2 and k3 represent weight values;

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

[0140] When R_adj = 0, it indicates that the refrigerant flow is qualified and no adjustment is needed;

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

[0142] S32, when 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 :

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

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

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

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

[0147] Embodiment 5

[0148] This embodiment is an explanation and description in embodiment 1, specifically, S3 includes: S4 includes:

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

[0150]

[0151] wherein, ΔP evap,i represents the change in evaporating pressure of the i-th temperature control zone according to the new refrigerant flow M new,i represents the change in evaporating pressure after adjustment, ΔP cond,i represents the change in evaporating pressure of the i-th temperature control zone according to the new refrigerant flow M new,i represents the change in condensing pressure after adjustment, Δt represents the time interval; the changes in evaporating pressure and condensing pressure are calculated according to the new refrigerant flow adjustment. These changes reflect the impact of refrigerant flow adjustment on the pressure of the temperature control zone. This parameter is used to consider the time factor of pressure change, so that the calculation can reflect the dynamic response of the system in actual operation.

[0152] S42, a pressure stability threshold E is preset, and a pressure stability index P stb,i of the i-th temperature control zone is calculated and compared with the pressure stability threshold E. If P stb,i >E, it indicates that the pressure fluctuation of the temperature control zone is abnormal, and the pressure is too large;

[0153] If P stb,i <E, it indicates that the pressure fluctuation of the temperature control zone is abnormal, and the pressure is too small, causing additional energy waste;

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

[0155] S43, when receiving the second optimization instruction, the new frequency F new,i of the variable frequency compressor of the i-th temperature control zone is calculated according to the following formula:

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

[0157] wherein, K f represents a frequency adjustment coefficient for smoothing the variable frequency adjustment, and the value range is set to be between 0.1-5.0;

[0158] When P stb,i >E or P stb,i <E, the variable frequency compressor is adjusted according to the new frequency F new,i of the variable frequency compressor of the i-th temperature control zone.

[0159] S44, after adjusting the variable frequency compressor according to the new frequency F new,i of the variable frequency compressor of the i-th temperature control zone, the new refrigerant flow Mnew,i To ensure that the instruction requirements are matched and to prevent overcooling or overheating, the second refrigerant flow M of the i-th temperature control area is calculated using the following formula: 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 adjustment coefficient, which controls the flow adjustment range; synchronously adjust 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.

[0162] In this embodiment, after adjusting the frequency of the variable frequency compressor, the refrigerant flow rate needs to be adjusted synchronously to ensure that the refrigerant flow rate matches the new frequency to prevent overcooling or overheating. new,2,i The new variable frequency compressor frequency F of the i-th temperature control zone of the variable frequency compressor new,i The adjustment amplitude is synchronized to ensure that the adjustment amplitude of the refrigerant flow rate is consistent with the change of the compressor frequency. This embodiment promotes the improvement of the energy efficiency of the refrigerator, stabilizes the cooling effect and reduces energy waste by synchronously adjusting the variable frequency compressor frequency and the refrigerant flow rate.

[0163] The threshold is set to facilitate comparison. The size of the threshold depends on the amount of sample data and the number of bases set by technicians in this field for each set of sample data; as long as it does not affect the proportional relationship between the parameter and the quantized value.

[0164] The above formulas are obtained by collecting a large amount of data and performing software simulation, and a formula close to the actual value is selected. The coefficients in the formula are set by those skilled in the art according to actual conditions. The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, can make equivalent replacements or changes based on the technical solution and inventive concept of the present invention, which 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 in advance, set up monitoring points in each temperature control area, and collect and obtain the operating parameters in each temperature control area, including the evaporation temperature of the i-th temperature control area. , condensation temperature , compressor frequency , refrigerant flow , evaporation pressure and condensing pressure , establish a set of operating parameters; S2. Collect 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 of the i-th temperature-controlled area. , 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 of the i-th temperature control area is constructed , and preset the state efficiency threshold, if the operating state coefficient of the i-th temperature control area If it is lower than the state efficiency threshold, the first optimization instruction is triggered; S2 includes: S21. In each temperature-controlled area, monitor and record cargo load information and manual operation behavior information, and establish a regional load set. The regional load set includes: the number of regional cargo in the i-th temperature-controlled area , average temperature of regional cargo , average temperature of new goods , Regional cabinet door opening and closing frequency and regional free storage capacity ; S22. After cleaning and normalizing the regional load set, calculate and obtain the load index of the i-th temperature control area ; S23, preset the load threshold, and set the load index of the i-th temperature control area Compare with the load threshold to determine the load level of the temperature control area, including: in, and Indicates that the first load threshold and the second load threshold are set according to the design and usage environment of the refrigerator, and are dynamically adjusted according to actual needs; The load index of the i-th temperature control area The way to obtain is: S221. First, calculate the impact of cargo load on the temperature control area and calculate the load impact index of the i-th temperature control area. : ; Where, Indicates the ideal temperature setting for the freezer. This formula reflects the load impact caused by the quantity of goods and the difference between the temperature of the goods and the set temperature. The greater the quantity of goods and the temperature, the higher the freezer load, and vice versa. S222. Calculate the manual operation impact index of the i-th temperature control area : ; Where, represents the external ambient temperature of the i-th temperature control area, Indicates the switching frequency of the gate; Manual operation impact index of the i-th temperature control area Indicates that the load increase caused by manual operation, frequent door opening or the addition of new high-temperature goods will increase the load of the freezer, thereby affecting its cooling efficiency; S223: Combine the load impact index of the i-th temperature control area obtained in S221 and S222 and the manual operation impact index of the i-th temperature control area , calculate the load index of the i-th temperature control area using the following formula : ; S3, after receiving the first optimization instruction, extract the evaporation temperature of the i-th temperature control area in the operating parameter set obtained in step S1 , condensation temperature and compressor frequency , calculate the refrigerant flow regulation index , and based on the refrigerant flow adjustment index , obtain the new refrigerant flow rate of the ith temperature control area , to match the refrigeration needs of the freezer; S4. Real-time monitoring of the evaporation pressure of the i-th temperature control area and condensing pressure , generate the pressure stability index of the i-th temperature control area , to determine whether it is necessary to adjust the operating parameters of the variable frequency compressor; preset pressure stability threshold E, if When , 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 rate of the i-th temperature control area Perform synchronization adjustments.

2. The variable frequency compressor control optimization method based on a commercial refrigerator according to claim 1 is characterized in that: Step S1 includes: S11. Divide the interior space of the commercial refrigerator into multiple levels of temperature-controlled areas, where the temperature-controlled 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 of the i-th temperature control area in real time. ; The temperature sensor inside the evaporator monitors the temperature of the refrigerant during evaporation to obtain the evaporation temperature of the i-th temperature control area ; Install a temperature sensor in the condenser to monitor the condensing temperature of the i-th temperature control area in real time ; Monitor the operating frequency of the compressor through the Hall sensor or speed sensor to obtain the compressor frequency of the i-th temperature control area ; The flow rate of the refrigerant in the pipeline is detected by the flow sensor to obtain the refrigerant flow rate of the i-th temperature control area ; The evaporation pressure is monitored by the pressure sensor installed on the evaporator to obtain the evaporation pressure of the i-th temperature control area. ; The condensing pressure is monitored by the pressure sensor installed on the condenser to obtain the condensing pressure of the i-th temperature control area. ; 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 a commercial refrigerator according to claim 1, 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 zone is abnormal, which not only wastes cooling resources but also leads to unstable operating efficiency. A first strategy is generated: increase the current cargo inventory by 10%-20% and increase the proportion of cold storage medium by 2%-3%. The cold storage medium includes frozen bottles and cold plates. When the second load level is identified, it means that the load of the i-th temperature control zone is normal and the operating efficiency is qualified, and no optimization adjustment is required; When the third-highest load level is identified, indicating an abnormal load in the i-th temperature-controlled zone, a second strategy is generated to reduce the current cargo inventory by 10%-20% and increase the proportion of cold-insulating media by 4%-6% to help alleviate temperature fluctuations.

4. The variable frequency compressor control optimization method based on a commercial refrigerator according to claim 3 is characterized in that: S2 also includes: S25. After the first and second strategies are implemented, extract the evaporation pressure of the i-th temperature control area , condensing pressure , compressor frequency and refrigerant flow , combined with the load index of the i-th temperature control area After dimensionless processing, the operating state coefficient of the i-th temperature control area is calculated by the following formula: : ; S26, preset the state efficiency threshold, and set the operating state coefficient of the i-th temperature control area Compare with the state efficiency threshold to determine whether the operating efficiency is qualified, including: If the operating state coefficient of the i-th temperature control area ≥ the state efficiency threshold, it means that the current temperature control area is operating at a qualified efficiency and continues to operate; If the operating state coefficient of the i-th temperature control area < the 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.

5. 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 of the i-th temperature control area in the operating parameter set obtained in step S1. , condensation temperature and compressor frequency , after dimensionless processing, the refrigerant flow regulation index is calculated by the following formula : ; Where, Indicates the set target evaporation temperature. Indicates the set target condensing temperature. Indicates the nominal operating frequency of the compressor; Indicates the weight value; when , indicating that the refrigerant flow rate needs to be increased to enhance the cooling effect; when , indicating that the refrigerant flow rate is qualified and no adjustment is required; when , indicating that the refrigerant flow needs to be reduced to avoid overcooling; S32, when identifying or When , the new refrigerant flow rate of the i-th temperature control area is calculated by the following formula : ; Where, Indicates the standard refrigerant flow rate in the temperature control area of ​​the refrigerator. is the refrigerant flow adjustment coefficient, which controls the flow adjustment range; like Positive or When it is negative, the new refrigerant flow rate of the i-th temperature control area Make adjustments.

6. The variable frequency compressor control optimization method based on a commercial refrigerator according to claim 1, characterized in that S4 include: S41, real-time monitoring of the evaporation pressure of the i-th temperature control area and condensing pressure , the pressure stability index of the i-th temperature control area is calculated by the following formula : ; in, Indicates the new refrigerant flow rate of the i-th temperature control area The increment of evaporation pressure change after adjustment, Indicates the new refrigerant flow rate of the i-th temperature control area The condensing pressure change increment after Indicates a time interval; S42: Preset the pressure stability threshold E and set the pressure stability index of the i-th temperature control area Compared with the pressure stability threshold E, if , it means that the pressure fluctuation in the temperature control area is abnormal and the pressure is too high; like , 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 If , it is determined that the operating parameters of the variable frequency compressor need to be adjusted, triggering the second optimization instruction; if , 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.

7. The variable frequency compressor control optimization method based on a commercial refrigerator according to claim 6, characterized in that: The S4 also includes: S43, after receiving the second optimization instruction, calculate the new variable frequency compressor frequency of the i-th temperature control area using the following formula: : ; in, Indicates the frequency adjustment coefficient, which is used for smooth frequency conversion adjustment; the value range is set between 0.1-5.0; when When the frequency of the new variable frequency compressor in the i-th temperature control area is Adjust the variable frequency compressor.

8. The variable frequency compressor control optimization method based on a commercial refrigerator according to claim 7, characterized in that: The S4 also includes: S44, according to the new variable frequency compressor frequency of the i-th temperature control area After adjusting the variable frequency compressor, the new refrigerant flow needs to be adjusted synchronously To ensure that the instruction requirements are matched and to prevent overcooling or overheating, the second refrigerant flow rate of the i-th temperature control area is calculated using the following formula: : ; in, is the refrigerant flow adjustment coefficient, which controls the flow adjustment range; synchronously adjusts the second refrigerant flow of the i-th temperature control area To match the new variable frequency compressor frequency of the i-th temperature control area synchronization requirements.

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