Temperature control method of cold storage machine

Abstract

The invention relates to the technical field of temperature control of cold storage machines, and provides a temperature control method of cold storage machines, which comprises the following steps that S1, a target cold storage temperature value is set, a wire controller sends a refrigeration instruction to all cold storage machines, and the cold storage machines start compressors corresponding to the cold storage machines after receiving the refrigeration instruction; s2, continuously obtaining temperature values measured by temperature sensors on all the cold storage machines; s3, selecting a temperature value measured by a temperature sensor of a certain cold storage machine as a current cold storage temperature value; s4, correcting the abnormal temperature sensors according to the temperature measurement conditions of all the temperature sensors in the past first preset time length; wherein the temperature value measured by the abnormal temperature sensor cannot be used as the current temperature value of the refrigeration house; and S5, when the current cold storage temperature value reaches the target cold storage temperature value, the cold storage machine closes a compressor corresponding to the cold storage machine.

Description

Technical Field

[0001] The invention relates to the technical field of temperature control of cold storage machines, in particular to a temperature control method of a cold storage machine. Background Art

[0002] With the widespread application of modern large-scale cold storage in logistics, food storage, and drug storage, the temperature control system of cold storage is essential to ensure the storage conditions of items. In order to meet the requirements of precise temperature control, multiple cold storage machines (refrigeration machines) are usually used to work together. These cold storage machines are usually equipped with temperature sensors to monitor the temperature in the cold storage in real time, and the compressor of the cold storage machine is started and stopped by the wire controller to achieve the regulation of the temperature of the cold storage.

[0003] However, in actual applications, due to the location of the cold storage machines, the installation differences of the temperature sensors and their accuracy, the temperature sensors of the various cold storage machines in the cold storage often have certain measurement errors, which may cause deviations in the temperatures measured by the temperature sensors of each cold storage machine, thereby affecting the temperature control effect of the entire cold storage. Sometimes, even if the cold storage temperature has reached the preset target, some cold storage machines still fail to shut down synchronously, causing the cold storage system to run for a long time.

[0004] Long-term asynchronous operation will not only increase energy consumption and fail to achieve energy-saving effects, but may also lead to excessive use of certain cold storage machines and increase wear of mechanical parts. This uneven operating state will accelerate the aging of some cold storage machines and affect their service life, which will in turn lead to an increase in the maintenance cost of the entire cold storage system and may affect the storage conditions of items in the cold storage.

[0005] Therefore, the existing cold storage temperature control system needs an improved temperature control method to ensure that each cold storage machine can be shut down synchronously through a more accurate temperature measurement and correction mechanism, so as to achieve energy saving and increase the service life of the equipment. Summary of the invention

[0006] In view of the above-mentioned defects, the purpose of the present invention is to propose a temperature control method for a cold storage machine, which aims to achieve accurate synchronization of the temperatures of multiple cold storage machines by real-time monitoring, comparison and correction of the temperature sensor data of each cold storage machine, thereby solving the problem of non-synchronous shutdown caused by temperature sensor errors.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] A temperature control method for a cold storage machine, the temperature control method is applied to a plurality of cold storage machines arranged in a cold storage, the cold storage machine is provided with a temperature sensor, a wire controller is arranged in the cold storage, the wire controller is used to send a control instruction to control the start and stop of a compressor in the cold storage machine, the temperature control method comprises the following steps:

[0009] S1: Set the target cold storage temperature value, the wired controller sends a cooling command to all cold storage machines, and the cold storage machines start the corresponding compressors after receiving the cooling command;

[0010] S2: Continuously obtain the temperature values ​​measured by the temperature sensors on each cold storage machine;

[0011] S3: According to the comparison between the obtained temperature values ​​and the comparison between the temperature value measured by the temperature sensor of the first cold storage machine and the temperature value of the remaining temperature sensors when the temperature value reaches the target cold storage temperature value, the temperature value measured by the temperature sensor of a cold storage machine is selected as the current cold storage temperature value;

[0012] S4: performing a correction operation on the abnormal temperature sensor according to the temperature measurement conditions of all temperature sensors within the first preset time length in the past;

[0013] Among them, the temperature value measured by the abnormal temperature sensor cannot be used as the current cold storage temperature value;

[0014] S5: When the current cold storage temperature reaches the target cold storage temperature, a stop command is sent to the wire controller. After receiving the stop command, the wire controller forwards the stop command to all cold storage machines, and the cold storage machines shut down the corresponding compressors.

[0015] Preferably, in step S3, it includes obtaining a refrigeration mode of the cold storage;

[0016] When the refrigeration mode is the item refrigeration mode, a cold storage machine whose interval with the item to be refrigerated is less than a preset distance is used as a target cold storage machine;

[0017] If the number of target cold storage machines is 1, the temperature value measured by the temperature sensor of the target cold storage machine is used as the current cold storage temperature value;

[0018] If the number of target cold storage machines is greater than one, a first average value of the temperature values ​​measured by the temperature sensors of all target cold storage machines is calculated, and the first average value is used as the current cold storage temperature value.

[0019] Preferably, step S3 includes:

[0020] When the temperature value measured by a temperature sensor reaches the target cold storage temperature value, the temperature values ​​measured by the remaining temperature sensors are monitored in real time;

[0021] If within the second preset time length, the temperature value measured by another temperature sensor reaches the target cold storage temperature value, then the positional relationship between the two temperature sensors is determined;

[0022] When two temperature sensors whose measured temperature values ​​reach the target cold storage temperature value are in adjacent positions, the temperature value measured by the other adjacent temperature sensor of the temperature sensor whose measured temperature value reaches the target cold storage temperature value for the first time is selected as the current cold storage temperature value;

[0023] When the two temperature sensors are in non-adjacent positions, the temperature value measured by the temperature sensor that is in the center of the two temperature sensors in space is selected as the current cold storage temperature value.

[0024] Preferably, step S3 includes:

[0025] If the difference between the highest value and the lowest value of the temperature values ​​measured by the temperature sensors is less than the first temperature threshold, the average value of the temperature values ​​measured by the temperature sensors of all the cold storage machines is taken as the current cold storage temperature value.

[0026] Preferably, step S3 includes:

[0027] If the difference between the highest temperature value and the remaining temperature values ​​measured by each temperature sensor is greater than the second temperature threshold, the highest temperature value measured is removed, and the average temperature value is calculated based on the remaining temperature values ​​measured as the current cold storage temperature value.

[0028] Preferably, step S4 includes:

[0029] Obtaining changes in temperature values ​​measured by all temperature sensors within a first preset time length in the past;

[0030] If the temperature value measured by the temperature sensor of the same cold storage machine reaches the target cold storage temperature value for the first time in a row, and the difference between the highest value and the remaining temperature values ​​measured by all temperature sensors is greater than the third temperature threshold, then the temperature sensor whose measured temperature value reaches the target cold storage temperature value for the first time in a row is subject to accuracy verification.

[0031] Furthermore, step S4 includes:

[0032] If the accuracy verification result of the temperature sensor to be verified is qualified, then obtaining the change of the temperature values ​​measured by all temperature sensors within the past first preset time length;

[0033] The temperature value measured by the temperature sensor whose measured temperature value is at the lowest proportion of the longest time length among all sensors is selected as the current cold storage temperature value.

[0034] Furthermore, step S4 includes:

[0035] If the accuracy verification result of the temperature sensor to be verified is unqualified, a correction operation is performed on the unqualified temperature sensor:

[0036] Use a reference temperature sensor of the same model to detect the temperature of the cold storage and obtain a reference temperature curve;

[0037] Compare the reference temperature curve with the current temperature curve of the temperature measured by the temperature sensor to be calibrated to obtain a comparison result;

[0038] When the comparison result is a linear error, a linear correction operation is performed on the temperature sensor to be corrected;

[0039] When the comparison result is a nonlinear error, the temperature curve measured by the temperature sensor to be calibrated is divided into several small intervals, and the temperature sensor to be calibrated is calibrated according to the values ​​of the reference temperature curve and the current temperature curve in the small intervals.

[0040] Furthermore, the linear correction operation satisfies the relationship:

[0041] T l =a×T0+b;

[0042] Among them, T l represents the degree of the temperature sensor after the linear correction operation is performed, a represents the strength of the relationship between the sensor reading and the corrected output, and b represents the offset.

[0043] Furthermore, the temperature sensor to be calibrated is calibrated according to the values ​​of the reference temperature curve and the current temperature curve in the small interval, satisfying the relationship:

[0044]

[0045] Among them, T corrected Represents the temperature value measured by the calibrated temperature sensor, T measured Indicates the temperature value measured by the temperature sensor to be calibrated, T reference2 and T reference1 Respectively represent the measured values ​​of the reference temperature sensor at the end point and the starting point of the small interval, T measured2 and T measured1 Indicates the measured values ​​of the temperature sensor to be calibrated at the end point and the start point of the small interval.

[0046] One of the above technical solutions has the following advantages or beneficial effects:

[0047] The present invention selects the temperature value measured by the temperature sensor of a certain cold storage machine as the current cold storage temperature value according to the comparison between the various temperature values ​​obtained, so as to more accurately reflect the actual temperature state in the cold storage and avoid the influence of the temperature fluctuation of a single sensor on the overall temperature control; according to the comparison between the temperature value measured by the temperature sensor of the first cold storage machine and the remaining temperature sensors when the temperature value reaches the target cold storage temperature value, the appropriate temperature sensor data is selected as the cold storage temperature value, which can effectively avoid the control error caused by the improper position of the temperature sensor and improve the stability of the cold storage temperature control; through the accuracy verification step, inaccurate sensors can be effectively identified and corrected, so as to avoid the interference of inaccurate temperature data on the temperature control of the cold storage machine and ensure the long-term stable operation of the temperature control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0049] Figure 1 is a flow chart of a temperature control method for a cold storage machine provided by an embodiment of the present invention;

[0050] Figure 2 It is a correction flow chart when the accuracy verification result of the temperature sensor to be verified in the temperature control method of the cold storage machine provided by the embodiment of the present invention is unqualified;

[0051] Figure 3 The present invention is a diagram showing the position relationship between objects and the cold storage machine during refrigeration in the cold storage of the temperature control method of the cold storage machine provided by the embodiment of the present invention. DETAILED DESCRIPTION

[0052] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0053] In this application, the terms "comprises", "comprising" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0054] A temperature control method for a cold storage machine, the temperature control method is applied to a plurality of cold storage machines arranged in a cold storage, the cold storage machine is provided with a temperature sensor, the cold storage is provided with a wire controller, the wire controller is used to send a control instruction to control the start and stop of the compressor in the cold storage machine, such as Figure 1 As shown, in a preferred embodiment of the present invention, the temperature control method comprises the following steps:

[0055] S1: Set the target cold storage temperature value, the wired controller sends a cooling command to all cold storage machines, and the cold storage machines start the corresponding compressors after receiving the cooling command;

[0056] In the temperature control system of the cold storage, setting the target cold storage temperature value is the key first step to ensure that the cold storage environment meets the storage requirements. The target cold storage temperature value is set according to the optimal storage temperature of the items to be stored (such as food, medicine, etc.). When the temperature control system is started, the wire controller is responsible for issuing a refrigeration command and conveying this target temperature to all cold storage machines. After receiving the command, the cold storage machine will start its compressor and start the refrigeration process. Through the coordinated work of multiple cold storage machines, the entire cold storage environment will quickly approach the set target temperature. The role of setting the target temperature value is to ensure that all cold storage machines work under a unified goal, thereby ensuring the coordination and consistency of the cold storage temperature.

[0057] S2: Continuously obtain the temperature values ​​measured by the temperature sensors on each cold storage machine;

[0058] One of the core elements of the temperature control system is real-time monitoring of temperature. Each cold storage machine is equipped with a temperature sensor, which continuously monitors the temperature inside the cold storage. The temperature of the cold storage is determined by summarizing the measurement data of multiple temperature sensors. Therefore, the data fed back by the temperature sensor of each cold storage machine will directly affect the temperature control effect of the entire cold storage. By continuously obtaining and updating the temperature values ​​of the temperature sensors of each cold storage machine, the temperature control system can grasp the overall temperature conditions of the cold storage in real time. The principle is that by continuously collecting the temperature data of the cold storage machine, the temperature control system can dynamically adjust the temperature to ensure that the temperature in the cold storage is always at the target temperature, thereby avoiding uneven cooling or over-cooling caused by excessive temperature differences.

[0059] S3: According to the comparison between the obtained temperature values ​​and the comparison between the temperature value measured by the temperature sensor of the first cold storage machine and the temperature value of the remaining temperature sensors when the temperature value reaches the target cold storage temperature value, the temperature value measured by the temperature sensor of a cold storage machine is selected as the current cold storage temperature value;

[0060] Due to the different number and location of cold storage machines, there may be certain differences in the temperature of each location in the cold storage. Therefore, in a cold storage with a large area, the data of a single temperature sensor cannot accurately reflect the temperature condition of the entire cold storage. In order to avoid the control deviation caused by the temperature sensor error of a certain cold storage machine, it is necessary to select the most appropriate cold storage temperature value by comparing the temperature sensor data of each cold storage machine. The stacking of items in the cold storage will also affect the air flow, resulting in lower or higher temperatures in some areas, or the location of the cold storage machine will affect the uniformity of the temperature. The temperature close to the cold storage machine is usually lower, while the temperature far away from the cold storage machine is higher. The working conditions of different cold storage machines may cause local temperature differences. By comparing the temperature values ​​measured by each temperature sensor, the temperature distribution inside the cold storage can be more accurately judged. Only after comparing the data of different sensors can the most representative temperature value be selected as the temperature reference for the entire cold storage.

[0061] If you only rely on the measurement data of one temperature sensor to determine the temperature of the entire cold storage, it may cause errors in temperature control, especially when the temperature in certain areas of the cold storage fluctuates abnormally, such as: sensor failure: a temperature sensor may produce inaccurate readings due to failure or external interference; local temperature difference: the temperature of local areas in the cold storage varies greatly, and some areas may produce abnormally high or low temperatures due to special circumstances (such as the wind direction of the air conditioner, frequent door openings, etc.).

[0062] When the temperature value measured by the temperature sensor of the first cold storage machine reaches the target temperature, it needs to be compared with the data of other sensors to ensure that the temperature adjustment in the cold storage is coordinated. The specific reasons include: ensuring temperature uniformity: if the temperature of a certain area reaches the target temperature first, but other areas have not yet reached the target temperature, it may mean that there is an uneven temperature distribution in the cold storage. By comparing with other sensors, it can be confirmed whether the temperatures of all areas tend to be consistent to ensure the uniform temperature inside the cold storage; dynamically adjust the working status of the cold storage machine: if the temperature value measured by the temperature sensor of the first cold storage machine reaches the target cold storage temperature value first, and the temperatures of other cold storage machines do not meet the standard, this may be due to the different distribution of air conditioners. According to this comparison, it is necessary to optimize the working arrangement of the cold storage machine to avoid shutting down some cold storage machines too early and prevent overheating of some areas.

[0063] When the temperature value measured by the temperature sensor of the first cold storage machine reaches the target cold storage temperature value, the comparison with the remaining temperature sensors includes not only temperature comparison but also spatial position comparison. The main reason for deciding which temperature value to select as the current cold storage temperature value based on the positional relationship of different temperature sensors is that adjacent sensors are usually located in areas with more uniform temperature distribution, so their temperature values ​​should be relatively close. By selecting the temperature values ​​of adjacent sensors, the current temperature state of the cold storage can be more accurately reflected. For sensors in non-adjacent positions, they may be located in different temperature areas in the cold storage, so their temperature values ​​may be different. In this case, the temperature value of the sensor in the middle between the two can be selected to avoid extreme situations and ensure a more balanced overall temperature control.

[0064] S4: performing a correction operation on the abnormal temperature sensor according to the temperature measurement conditions of all temperature sensors within the first preset time length in the past;

[0065] Among them, the temperature value measured by the abnormal temperature sensor cannot be used as the current cold storage temperature value;

[0066] Temperature sensors may have measurement errors due to long-term use, position differences, installation deviations or external environmental factors (such as humidity, air flow, etc.). These errors will cause the temperature values ​​of some cold storage machines to deviate from the actual temperature, thereby affecting the overall temperature control effect of the cold storage. In order to ensure accurate control of the cold storage temperature, these abnormal sensors need to be calibrated. By monitoring the temperature data within the first preset time length in the past (such as 10 minutes after the refrigeration mode is started), it is possible to find out which temperature sensors have deviations and take corresponding corrective measures. The correction can be completed by adjusting the sensor readings, ignoring abnormal data or recalibrating the sensor. Through this process, the stability of the cold storage temperature can be guaranteed, and temperature inaccuracies caused by sensor errors can be avoided, further improving the reliability and accuracy of cold storage management.

[0067] S5: When the current cold storage temperature reaches the target cold storage temperature, a stop command is sent to the wire controller. After receiving the stop command, the wire controller forwards the stop command to all cold storage machines, and the cold storage machines shut down the corresponding compressors.

[0068] After cooling down the temperature to the set target value, unnecessary refrigeration work is stopped to achieve energy saving. According to the difference between the current cold storage temperature and the target temperature, it is judged whether the set temperature value has been reached. When the cold storage temperature reaches the target value, the compressor of the cold storage machine is turned off by sending a stop command to the wire controller to stop refrigeration. The stop of the compressor means that the cold storage no longer consumes additional energy, which can effectively avoid the long-term excessive operation of the cold storage machine, ensure the stability of the cold storage temperature, and effectively reduce energy consumption. In addition, the stop of the cold storage machine can also reduce the load of mechanical parts and extend the service life of the equipment. Through precise temperature control and shutdown control, it ensures that the cold storage neither wastes energy nor causes excessive wear of the equipment.

[0069] Preferably, in step S3, it includes obtaining a refrigeration mode of the cold storage;

[0070] When the refrigeration mode is the item refrigeration mode, a cold storage machine whose interval with the item to be refrigerated is less than a preset distance is used as a target cold storage machine;

[0071] If the number of target cold storage machines is 1, the temperature value measured by the temperature sensor of the target cold storage machine is used as the current cold storage temperature value;

[0072] If the number of target cold storage machines is greater than one, a first average value of the temperature values ​​measured by the temperature sensors of all target cold storage machines is calculated, and the first average value is used as the current cold storage temperature value.

[0073] In step S3, the refrigeration mode of the cold storage needs to be determined first. The choice of refrigeration mode is related to the types of items in the cold storage and the temperature requirements. If the refrigeration mode is "item refrigeration mode", it means that the cold storage will focus on temperature control of the refrigerated items rather than a single temperature control of the entire cold storage area. In this mode, the cold storage will adjust the temperature according to the location of the items, the layout of the cold storage machines and their spacing to ensure that the temperature of the items reaches the required level.

[0074] In the item refrigeration mode, the cold storage machine whose distance to the items to be refrigerated is less than the preset value is selected as the target cold storage machine, because the temperature and refrigeration capacity of each cold storage machine will affect the distance requirement between it and the items. If the distance between the cold storage machine and the items is less than the preset distance, it means that the cold storage machine can refrigerate the items more effectively, so it is selected as the target cold storage machine. If the distance between the cold storage machine and the items is greater than the preset value, the conditions for selecting the target cold storage machine are not met, so it will not be included in the consideration range. Regardless of whether the temperature value measured by the temperature sensor of the cold storage machine reaches the target cold storage temperature value, it will not affect the opening and closing of the compressor. The preset distance can be related to the refrigeration capacity and efficiency of the cold storage machine, the types and temperature control requirements of the items in the cold storage, and the spatial layout of the cold storage machines in the cold storage.

[0075] If only one cold storage machine is selected as the target cold storage machine (that is, the number of cold storage machines whose distance to the items to be refrigerated is less than the preset value is 1), then the temperature sensor measurement value of the cold storage machine will be directly used as the temperature value of the current cold storage. Since there is only one target cold storage machine, there is no need for complex average calculation. The temperature value can be regarded as the actual temperature value of the entire cold storage area, and then the compressor will be stopped when the temperature value reaches the target cold storage temperature value.

[0076] If there are multiple cold storage machines that meet the conditions (that is, the number of cold storage machines whose distance to the items to be refrigerated is less than the preset distance is greater than 1), it is necessary to further calculate the first average value of the temperature sensor measurement values ​​of these cold storage machines. The first average value is calculated by adding up the temperature values ​​of multiple target cold storage machines and then dividing it by the number of target cold storage machines. This average value represents the temperature state of the entire cold storage area, which takes into account the refrigeration effects of multiple cold storage machines. By calculating the average value, the temperature conditions in the cold storage can be more comprehensively evaluated, thereby making more accurate temperature adjustments.

[0077] like Figure 3 As shown, in the cold storage, item D1 is on the left, item D2 is on the right, cold storage machine 1 is below item D1, and the distance from the bottom of item D1 is 0.8 meters, which meets the preset spacing requirement of less than 1 meter; cold storage machine 2 is on the left side of item D1, and the distance from the left side of item D1 is 0.9 meters, which also meets the requirement. Cold storage machine 3 is located on the upper side between item D1 and item D2, and the distance between cold storage machine 3 and item D1 and item D2 is 0.7 meters. Cold storage machine 4 is located on the right side of cold storage machine 1, and the distance between cold storage machine 4 and item D1 and item D2 is 0.7 meters, which meets the preset spacing; cold storage machine 5 is located in the upper right corner, and the distance from the upper right corner of item D2 is 1.2 meters, and the spacing is greater than the preset 1 meter, so it does not meet the minimum spacing requirement, so cold storage machines 1, 2, 3 and 4 are selected as target cold storage machines.

[0078] Preferably, step S3 includes:

[0079] When the temperature value measured by a temperature sensor reaches the target cold storage temperature value, the temperature values ​​measured by the remaining temperature sensors are monitored in real time;

[0080] If within the second preset time length, the temperature value measured by another temperature sensor reaches the target cold storage temperature value, then the positional relationship between the two temperature sensors is determined;

[0081] When two temperature sensors whose measured temperature values ​​reach the target cold storage temperature value are in adjacent positions, the temperature value measured by the other adjacent temperature sensor of the temperature sensor whose measured temperature value reaches the target cold storage temperature value for the first time is selected as the current cold storage temperature value;

[0082] When the two temperature sensors are in non-adjacent positions, the temperature value measured by the temperature sensor that is in the center of the two temperature sensors in space is selected as the current cold storage temperature value.

[0083] Specifically, when the temperature value measured by the temperature sensor of a cold storage machine reaches the target cold storage temperature, the temperature changes of other temperature sensors are monitored in real time. Because temperature regulation in the cold storage is usually not a task of a single location, the temperature needs to be evenly distributed throughout the cold storage. Therefore, it is necessary to monitor the readings of all sensors to ensure that the temperature values ​​at each location in the cold storage reach the target cold storage temperature values.

[0084] Within the set time window (the second preset time length), if the temperature value of another temperature sensor also reaches the target cold storage temperature value, the positional relationship of the two sensors will be further analyzed. The positional relationship of the sensors is determined to ensure temperature balance, because the temperature adjustment inside the cold storage does not only depend on the reading of a single sensor, but is also closely related to the distribution of other sensors. By judging their positions, the propagation and adjustment strategies of temperature changes can be reasonably inferred. If two temperature sensors are in adjacent positions and both measure temperature values ​​that reach the target cold storage temperature value, the temperature value measured by the adjacent sensor of the temperature sensor that reaches the target temperature value for the first time is selected as the current temperature value of the cold storage, because the temperature changes of sensors in adjacent positions will be more synchronous, and the selection of the temperature values ​​of adjacent sensors can reflect the stability and change trend of the current temperature in the cold storage, thereby effectively performing temperature control. Figure 3 As shown, if the temperature values ​​measured by the temperature sensors of cold storage machine 1 and cold storage machine 4 reach the target cold storage temperature value in sequence, the temperature value measured by the temperature sensor of cold storage machine 2 is selected as the current cold storage temperature value.

[0085] When two temperature sensors are in non-adjacent positions, the temperature value measured by the temperature sensor located in the middle between them is selected as the current temperature value of the cold storage. This is because the temperature changes measured by non-adjacent sensors may vary greatly. Therefore, the temperature value of the sensor in the middle position can more accurately reflect the temperature conditions inside the entire cold storage and avoid uneven temperature control due to abnormal readings of individual sensors. Figure 3 In the embodiment, if the temperature values ​​measured by the temperature sensors of cold storage machine 2 and cold storage machine 4 reach the target cold storage temperature value in turn, the temperature value measured by the temperature sensor of cold storage machine 1 is selected as the current cold storage temperature value.

[0086] Preferably, step S3 includes:

[0087] If the difference between the highest value and the lowest value of the temperature values ​​measured by the temperature sensors is less than the first temperature threshold, the average value of the temperature values ​​measured by the temperature sensors of all the cold storage machines is taken as the current cold storage temperature value.

[0088] Specifically, in order to determine whether the temperature inside the cold storage is uniform, first collect the temperature data measured by all temperature sensors, and calculate the highest and lowest temperature values. The difference between the maximum and minimum values ​​reflects the distribution range of the temperature in the cold storage. If the temperature difference is large, it means that the temperature in the cold storage is not yet balanced; if the temperature difference is small, it means that the temperature is close to uniform.

[0089] After obtaining the maximum and minimum values ​​of each sensor, the difference is compared with the preset first temperature threshold. The first temperature threshold can be set according to the use requirements of the cold storage, product storage requirements and equipment performance. When the temperature difference is less than this threshold, it means that the temperature variation range in the cold storage is small enough, the temperature has tended to be uniform, and meets the basic requirements of temperature control.

[0090] If the temperature difference between the highest and lowest values ​​is less than the first temperature threshold, it is considered that the temperature in the cold storage is basically balanced. At this time, the temperature values ​​measured by all temperature sensors are averaged. The purpose of averaging is to eliminate possible local temperature fluctuations and provide an accurate value representing the overall temperature state of the cold storage. The calculated average temperature value will be used as the "current cold storage temperature value" for subsequent temperature control adjustments. By using the average temperature value instead of a single reading of a local sensor, unnecessary control responses caused by abnormalities in individual sensors or local temperature fluctuations can be avoided, thereby improving the accuracy and efficiency of cold storage temperature control.

[0091] Preferably, step S3 includes:

[0092] If the difference between the highest temperature value and the remaining temperature values ​​measured by each temperature sensor is greater than the second temperature threshold, the highest temperature value measured is removed, and the average temperature value is calculated based on the remaining temperature values ​​measured as the current cold storage temperature value.

[0093] Specifically, the second temperature threshold is a preset standard value that defines the tolerance for temperature fluctuations. By checking all temperature values ​​one by one, it is confirmed whether the difference between the highest value and each of the remaining temperature values ​​is greater than the second temperature threshold. If the difference is greater than the second temperature threshold, it means that there is a large temperature difference between the highest value and the other temperature values, which may indicate that the sensor reading is abnormal, or the temperature at this location fluctuates violently, which does not meet the normal expectations of the temperature control system. In order to avoid this abnormal value affecting the overall temperature control of the cold storage, the highest temperature value will be removed, that is, it will no longer be used as the basis for calculating the current temperature of the cold storage. Then the average value of the sum of the remaining temperature values ​​measured is calculated. This average value can effectively prevent the abnormal data of a single temperature sensor from affecting the overall temperature control of the cold storage, thereby improving the stability and accuracy of temperature control.

[0094] Step S4 includes: obtaining the change of the temperature values ​​measured by all temperature sensors within the past first preset time length;

[0095] If the temperature value measured by the temperature sensor of the same cold storage machine reaches the target cold storage temperature value for the first time in a row, and the difference between the highest value and the remaining temperature values ​​measured by all temperature sensors is greater than the third temperature threshold, then the temperature sensor whose measured temperature value reaches the target cold storage temperature value for the first time in a row is subject to accuracy verification.

[0096] In this embodiment, firstly, the change of temperature data collected by all temperature sensors in the past period of time (first preset time length) is obtained, which helps to track the historical fluctuation of temperature, thereby providing a basis for subsequent temperature control decisions.

[0097] If within this time period, the temperature sensor of a cold storage machine reaches the target cold storage temperature value for the first time in a row, the readings of the temperature sensor will be further analyzed: If at this time, the difference between the highest temperature value measured by all temperature sensors and the temperature values ​​measured by all other sensors is greater than the set third temperature threshold, it means that the highest temperature value deviates significantly from the readings of other sensors and there are large temperature fluctuations, which may indicate that a sensor is faulty or the data is abnormal.

[0098] In this case, the temperature sensor will be verified for accuracy. Specifically, the data quality of the sensor needs to be rechecked, possibly by calibrating, testing the sensor hardware, or by cross-verifying other relevant information to confirm whether it is working properly. This can avoid unstable temperature control due to abnormalities in individual sensors and ensure that the temperature control system can continue to operate with high precision.

[0099] Furthermore, step S4 includes:

[0100] If the accuracy verification result of the temperature sensor to be verified is qualified, then obtaining the change of the temperature values ​​measured by all temperature sensors within the past first preset time length;

[0101] The temperature value measured by the temperature sensor whose measured temperature value is at the lowest proportion of the longest time length among all sensors is selected as the current cold storage temperature value.

[0102] Specifically, analyze the temperature values ​​measured by each temperature sensor during the time period, and pay special attention to the frequency and duration of the "minimum temperature value". The "minimum temperature value" here refers to the smallest temperature value recorded by each sensor in the past time period. Because the temperature of the cold storage should generally be kept within a specific range, and a temperature value that is too low may mean that the equipment is overcooled or inefficient, special attention should be paid to the occurrence of the minimum temperature state.

[0103] The length of time that each sensor is in the "lowest temperature value" state during the time period is counted, and the proportion is calculated. For example, the lowest temperature value of a sensor may account for 30% of the time, while that of another sensor may only be 10%. Then the temperature sensor with the highest proportion of the lowest temperature value in the past time period will be selected. This temperature sensor maintains the lowest temperature state for a long time during the time period. The temperature of the area with the lowest temperature for a long time needs to reach the target cold storage temperature to meet the refrigeration requirements of the cold storage. Therefore, the temperature value of the selected sensor (that is, the sensor with the highest proportion of the lowest temperature value) is used as the current temperature value of the cold storage, thereby ensuring the refrigeration effect of the cold storage and preventing insufficient refrigeration in some areas.

[0104] Furthermore, if Figure 2 As shown, step S4 includes the steps of:

[0105] If the accuracy verification result of the temperature sensor to be verified is unqualified, a correction operation is performed on the unqualified temperature sensor:

[0106] S41: Use a reference temperature sensor of the same model to detect the temperature of the cold storage to obtain a reference temperature curve;

[0107] S42: Compare the reference temperature curve with the current temperature curve of the temperature measured by the temperature sensor to be calibrated to obtain a comparison result;

[0108] S43: When the comparison result is a linear error, a linear correction operation is performed on the temperature sensor to be corrected;

[0109] S44: When the comparison result is a nonlinear error, the temperature curve of the temperature measured by the temperature sensor to be calibrated is divided into a plurality of small intervals, and the temperature sensor to be calibrated is calibrated according to the values ​​of the reference temperature curve and the current temperature curve in the small intervals.

[0110] Specifically, to ensure the accuracy of the calibration operation, you first need to use a verified, high-precision reference temperature sensor to measure the temperature of the cold storage. The reference sensor needs to have high accuracy and stability, and is an important benchmark for calibrating other temperature sensors. In the cold storage environment, the reference sensor records the curve of temperature changes over time, that is, the reference temperature curve. This reference temperature curve will be used as a comparison standard to help us understand the measurement error of the sensor to be calibrated in a specific environment. The accuracy of the reference sensor can provide a value close to the actual cold storage environment temperature. The error of the temperature sensor to be calibrated can be identified and corrected through comparison.

[0111] After measuring the temperature curve of the reference temperature sensor, it is necessary to compare it with the current temperature curve measured by the temperature sensor to be calibrated. The difference between the temperature values ​​of the two at each moment reflects the error of the sensor to be calibrated. By comparing, we can find the difference between the two temperature curves, and then determine whether the error is a linear error or a nonlinear error. The linear error is manifested as a relatively constant temperature difference in the entire measurement range, while the nonlinear error is manifested as a temperature difference that changes with the ambient temperature and is not a fixed constant.

[0112] If the comparison result shows that the error is a linear error, it means that the difference between the measured value of the temperature sensor to be corrected and the measured value of the reference sensor is a constant, or the error remains stable over the entire temperature range, which indicates that the sensor may have common offset problems, such as systematic zero drift or gain error. For linear errors, they are usually corrected through linear correction operations, that is, the output value of the temperature sensor to be corrected is adjusted to the measured value of the reference sensor through a simple mathematical model (such as addition or multiplication). The specific method can be to add or subtract a constant (if it is an offset error) or adjust the output value through a proportional factor (if it is a gain error).

[0113] If the comparison result shows that the error is a nonlinear error, it means that the error of the sensor to be corrected is not only constant, but also changes with temperature. Nonlinear error usually indicates that there is a complex relationship between the sensor's response curve and the actual temperature change, which may be affected by multiple factors such as temperature range, sensor material properties, and external environmental changes. When dealing with this error, it is first necessary to divide the temperature curve to be corrected into multiple small intervals. In each small interval, the error performance of the sensor to be corrected may be relatively simple, and can be corrected using a local linear correction method. Specifically, in each interval, the correction factor in the interval can be obtained by comparing the difference between the reference temperature curve and the sensor curve to be corrected. Then, the sensor to be corrected is corrected according to the error conditions in different intervals. This process can be achieved through interpolation, piecewise linear correction, etc., so that the error of the sensor in the entire temperature range is minimized.

[0114] Furthermore, the linear correction operation satisfies the relationship:

[0115] T l =a×T0+b;

[0116] Among them, T l represents the degree of the temperature sensor after the linear correction operation is performed, a represents the strength of the relationship between the sensor reading and the corrected output, and b represents the offset.

[0117] When performing linear calibration of a temperature sensor, the original sensor output T0 and the known standard temperature Tl The relationship between l =a×T0+b, where a and b are the correction coefficient and offset respectively. The a and b values ​​obtained through the calibration experiment can convert the original reading T0 of the sensor into a more accurate temperature value T l For example, assuming that a=1.05,b=-2.3 are obtained through calibration, when the original sensor reading T0 is 25℃, the corrected temperature T l T l =1.05×25-2.3=25.2°C, indicating that the corrected temperature is 0.2°C higher than the original reading, thereby improving the measurement accuracy.

[0118] Furthermore, the temperature sensor to be calibrated is calibrated according to the values ​​of the reference temperature curve and the current temperature curve in the small interval, satisfying the relationship:

[0119]

[0120] Among them, T corrected Represents the temperature value measured by the calibrated temperature sensor, T measured Indicates the temperature value measured by the temperature sensor to be calibrated, T measured2 and T measured1 Respectively represent the measured values ​​of the reference temperature sensor at the end point and the starting point of the small interval, T measured2 and T measured1 Indicates the measured values ​​of the temperature sensor to be calibrated at the end point and the start point of the small interval.

[0121] In this embodiment, within a small interval, the measured values ​​of the reference sensor are T reference1 =20℃ and T reference2 =30℃, and the measured values ​​of the sensors to be calibrated are T measured1 =22℃ and T measured2 =28℃. Now, the current measured value of the sensor to be calibrated is T measured =24℃, according to the calibration formula, we first calculate the proportional relationship between the sensor to be calibrated and the reference sensor, that is, 6 / 10=0.6, then we calculate the difference between the current reading of the sensor to be calibrated and the starting point reading, and get T measured -T measured1 =2°C. Finally, by multiplying the difference with the proportional factor, the correction value is 1.2°C, thus obtaining the corrected temperature value T corrected =24+1.2=25.2℃, which means that after calibration, the temperature reading of the sensor to be calibrated is adjusted from the original 24℃ to 25.2℃, which is closer to the actual measurement value of the reference sensor, ensuring the accuracy of temperature measurement.

[0122] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0123] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A temperature control method for a cold storage machine, the temperature control method is applied to a plurality of cold storage machines arranged in a cold storage, the cold storage machine is provided with a temperature sensor, the cold storage is provided with a wire controller, the wire controller is used to send a control instruction to control the start and stop of the compressor in the cold storage machine, characterized in that: The temperature control method comprises the following steps: S1: Set the target cold storage temperature value, the wired controller sends a cooling command to all cold storage machines, and the cold storage machines start the corresponding compressors after receiving the cooling command; S2: Continuously obtain the temperature values ​​measured by the temperature sensors on each cold storage machine; S3: According to the comparison between the obtained temperature values ​​and the comparison between the temperature value measured by the temperature sensor of the first cold storage machine and the temperature value of the remaining temperature sensors when the temperature value reaches the target cold storage temperature value, the temperature value measured by the temperature sensor of a cold storage machine is selected as the current cold storage temperature value; S4: performing a correction operation on the abnormal temperature sensor according to the temperature measurement conditions of all temperature sensors within the first preset time length in the past; Among them, the temperature value measured by the abnormal temperature sensor cannot be used as the current cold storage temperature value; S5: When the current cold storage temperature reaches the target cold storage temperature, a stop command is sent to the wire controller. After receiving the stop command, the wire controller forwards the stop command to all cold storage machines, and the cold storage machines shut down the corresponding compressors.

2. The temperature control method according to claim 1, characterized in that: In step S3, it includes obtaining the refrigeration mode of the cold storage; When the refrigeration mode is the item refrigeration mode, a cold storage machine whose interval with the item to be refrigerated is less than a preset distance is used as a target cold storage machine; If the number of target cold storage machines is 1, the temperature value measured by the temperature sensor of the target cold storage machine is used as the current cold storage temperature value; If the number of target cold storage machines is greater than one, a first average value of the temperature values ​​measured by the temperature sensors of all target cold storage machines is calculated, and the first average value is used as the current cold storage temperature value.

3. The temperature control method according to claim 1, characterized in that: Step S3 includes: When the temperature value measured by a temperature sensor reaches the target cold storage temperature value, the temperature values ​​measured by the remaining temperature sensors are monitored in real time; If within the second preset time length, the temperature value measured by another temperature sensor reaches the target cold storage temperature value, then the positional relationship between the two temperature sensors is determined; When two temperature sensors whose measured temperature values ​​reach the target cold storage temperature value are in adjacent positions, the temperature value measured by the other adjacent temperature sensor of the temperature sensor whose measured temperature value reaches the target cold storage temperature value for the first time is selected as the current cold storage temperature value; When the two temperature sensors are in non-adjacent positions, the temperature value measured by the temperature sensor that is in the center of the two temperature sensors in space is selected as the current cold storage temperature value.

4. The temperature control method according to claim 1, characterized in that: Step S3 includes: If the difference between the highest value and the lowest value of the temperature values ​​measured by the temperature sensors is less than the first temperature threshold, the average value of the temperature values ​​measured by the temperature sensors of all the cold storage machines is taken as the current cold storage temperature value.

5. The temperature control method according to claim 1, characterized in that: Step S3 includes: If the difference between the highest temperature value and the remaining temperature values ​​measured by each temperature sensor is greater than the second temperature threshold, the highest temperature value measured is removed, and the average temperature value is calculated based on the remaining temperature values ​​measured as the current cold storage temperature value.

6. The temperature control method according to claim 1, characterized in that: Step S4 includes: Obtaining changes in temperature values ​​measured by all temperature sensors within a first preset time length in the past; If the temperature value measured by the temperature sensor of the same cold storage machine reaches the target cold storage temperature value for the first time in a row, and the difference between the highest value and the remaining temperature values ​​measured by all temperature sensors is greater than the third temperature threshold, then the temperature sensor whose measured temperature value reaches the target cold storage temperature value for the first time in a row is subject to accuracy verification.

7. The temperature control method according to claim 6, characterized in that: Step S4 includes: If the accuracy verification result of the temperature sensor to be verified is qualified, then obtaining the change of the temperature values ​​measured by all temperature sensors within the past first preset time length; The temperature value measured by the temperature sensor whose measured temperature value is at the lowest proportion of the longest time length among all sensors is selected as the current cold storage temperature value.

8. The temperature control method according to claim 6, characterized in that: Step S4 includes: If the accuracy verification result of the temperature sensor to be verified is unqualified, a correction operation is performed on the unqualified temperature sensor: Use a reference temperature sensor of the same model to detect the temperature of the cold storage and obtain a reference temperature curve; Compare the reference temperature curve with the current temperature curve of the temperature measured by the temperature sensor to be calibrated to obtain a comparison result; When the comparison result is a linear error, a linear correction operation is performed on the temperature sensor to be corrected; When the comparison result is a nonlinear error, the temperature curve measured by the temperature sensor to be calibrated is divided into several small intervals, and the temperature sensor to be calibrated is calibrated according to the values ​​of the reference temperature curve and the current temperature curve in the small intervals.

9. The temperature control method according to claim 8, characterized in that: The linear correction operation satisfies the relationship: T l =a×T0+b; Among them, T l represents the degree of the temperature sensor after the linear correction operation is performed, a represents the strength of the relationship between the sensor reading and the corrected output, and b represents the offset.

10. The temperature control method according to claim 8, characterized in that: The temperature sensor to be calibrated is calibrated according to the value of the reference temperature curve and the current temperature curve in the small interval, satisfying the relationship: Among them, T corrected Represents the temperature value measured by the calibrated temperature sensor, T measurtd Indicates the temperature value measured by the temperature sensor to be calibrated, T reference2 and T reference1 Respectively represent the measured values ​​of the reference temperature sensor at the end point and the starting point of the small interval, T measured2 and T measured1 Indicates the measured values ​​of the temperature sensor to be calibrated at the end point and the start point of the small interval.

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