A temperature control method for a cold storage machine

Abstract

The application relates to the temperature control technical field of cold storage machines and discloses a temperature control method of a cold storage machine, which comprises the following steps: S1: setting a target cold storage temperature value, a line controller sending a refrigeration instruction to all cold storage machines, and the cold storage machines starting corresponding compressors after receiving the refrigeration instruction; S2: continuously acquiring temperature values measured by temperature sensors on 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: performing a correction operation on an abnormal temperature sensor according to temperature measurement conditions of all temperature sensors within a first preset time length; wherein the temperature value measured by the abnormal temperature sensor cannot be used as the current cold storage temperature value; and S5: when the current cold storage temperature value reaches the target cold storage temperature value, the cold storage machine stops the corresponding compressor.

Description

Technical Field

[0001] This invention relates to the field of temperature control technology for cold storage machines, and in particular to a temperature control method for cold storage machines. Background Technology

[0002] With the widespread application of modern large-scale cold storage in logistics, food storage, and pharmaceutical storage, the temperature control system of cold storage is crucial to ensuring the storage conditions of goods. To meet the requirements of precise temperature control, multiple cold storage units (refrigeration units) are usually used in conjunction. These units are typically equipped with temperature sensors to monitor the temperature inside the cold storage in real time, and the compressors of the cold storage units are started and stopped via wired controllers to regulate the temperature of the cold storage.

[0003] However, in practical applications, due to differences in the location of the cold storage units, the installation of temperature sensors, and their accuracy, the temperature sensors of each cold storage unit in the cold storage often have certain measurement errors. This may lead to deviations in the temperature measured by the temperature sensors of each cold storage unit, 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 units still fail to stop synchronously, resulting in the cold storage system running for a long time.

[0004] Prolonged asynchronous operation not only increases energy consumption and fails to achieve energy-saving effects, but may also lead to overuse of some cold storage units, increasing wear and tear on mechanical parts. This uneven operating state will accelerate the aging of some cold storage units, affecting their service life, which in turn leads to increased maintenance costs for the entire cold storage system and may affect the storage conditions of items inside the cold storage.

[0005] Therefore, existing cold storage temperature control systems need an improved temperature control method that uses more precise temperature measurement and correction mechanisms to ensure that all cold storage units can shut down synchronously, thereby achieving energy savings and extending the service life of the equipment. Summary of the Invention

[0006] To address the aforementioned shortcomings, the present invention aims to propose a temperature control method for cold storage machines. This method achieves precise temperature synchronization of multiple cold storage machines by real-time monitoring, comparison, and correction of temperature sensor data from each cold storage machine, thereby solving the problem of asynchronous shutdown caused by temperature sensor errors.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] A temperature control method for a cold storage unit, the method being applied to a plurality of cold storage units installed within a cold storage facility, each cold storage unit being equipped with a temperature sensor, and a wired controller being installed within the cold storage facility. The wired controller is used to send control commands to control the start and stop of the compressors within the cold storage units. The temperature control method includes the following steps:

[0009] S1: Set the target cold storage temperature value. The wired controller sends a refrigeration command to all cold storage units. After receiving the refrigeration command, the cold storage unit starts the compressor corresponding to it.

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

[0011] S3: Based on the comparison between the acquired temperature values ​​and the comparison between the temperature value measured by the temperature sensor of the first cold storage unit and the other temperature sensors when the temperature value reaches the target cold storage temperature value, select the temperature value measured by the temperature sensor of a certain cold storage unit as the current cold storage temperature value.

[0012] S4: Based on the temperature measurement data of all temperature sensors within the first preset time period, perform a calibration operation on the abnormal temperature sensors;

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

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

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

[0016] When the refrigeration mode is the item refrigeration mode, the cold storage machine that is less than the preset distance from the item to be refrigerated is taken as the target cold storage machine.

[0017] If there is only one target cold storage unit, the temperature value measured by the temperature sensor of the target cold storage unit will be used as the current cold storage temperature value.

[0018] If there is more than one target cold storage unit, calculate the first average value of the temperature values ​​measured by the temperature sensors of all target cold storage units, and use the first average value as the current cold storage temperature value.

[0019] Preferably, step S3 includes:

[0020] When the temperature value measured by one of the temperature sensors reaches the target cold storage temperature value, the temperature values ​​measured by the other temperature sensors are monitored in real time.

[0021] If, within the second preset time period, 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 that have measured temperature values ​​that 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 that first measured the target cold storage temperature value is selected as the current cold storage temperature value.

[0023] When two temperature sensors are not in adjacent positions, the temperature value measured by the temperature sensor that is in the middle position in space is selected as the current cold storage temperature value.

[0024] Preferably, step S3 includes:

[0025] If the difference between the highest and lowest temperature values ​​measured by each temperature sensor is less than the first temperature threshold, then the average value of the temperature values ​​measured by all the temperature sensors of the cold storage unit 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, then the highest temperature value is removed, and the average temperature value is calculated based on the remaining temperature values ​​as the current cold storage temperature value.

[0028] Preferably, step S4 includes:

[0029] Obtain the changes in temperature values ​​measured by all temperature sensors within a first preset time period.

[0030] If the temperature values ​​measured by the temperature sensors of the same cold storage unit reach the target cold storage temperature value for the first time consecutively, and the difference between the highest value and the remaining temperature values ​​among all the temperature values ​​measured by the temperature sensors is greater than the third temperature threshold, then the accuracy of the temperature sensor whose measured temperature value reaches the target cold storage temperature value for the first time consecutively is verified.

[0031] Furthermore, step S4 includes:

[0032] If the accuracy verification result of the temperature sensor to be verified is qualified, then the changes in temperature values ​​measured by all temperature sensors within the first preset time period are obtained.

[0033] The temperature value measured by the temperature sensor with the longest duration of time when the measured temperature value is the lowest among all sensors is selected as the current temperature value of the cold storage.

[0034] Furthermore, step S4 includes:

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

[0036] The temperature of the cold storage was measured using a reference temperature sensor of the same model to obtain a reference temperature curve;

[0037] The reference temperature curve is compared with the current temperature curve measured by the temperature sensor to be calibrated to obtain the 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 of the temperature measured by the temperature sensor to be calibrated is divided into several small intervals. The temperature sensor to be calibrated is then calibrated based on the values ​​of the reference temperature curve and the current temperature curve within the small intervals.

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

[0041] T l = a × T0 + b;

[0042] Among them, T l This indicates the temperature sensor reading after performing a linear correction operation. '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 based on the values ​​of the reference temperature curve and the current temperature curve within a small interval, satisfying the following relationship:

[0044]

[0045] Among them, T corrected T represents the temperature value measured by the calibrated temperature sensor. measured T represents the temperature value measured by the temperature sensor to be calibrated. reference2 and T reference1 T represents the measured values ​​of the reference temperature sensor at the end and start points between cells, respectively. measured2 and T measured1 This indicates the measured values ​​of the temperature sensor to be calibrated at the end and start points between cells.

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

[0047] This invention selects the temperature value measured by a specific temperature sensor in a cold storage unit as the current cold storage temperature by comparing the acquired temperature values. This more accurately reflects the actual temperature state inside the cold storage and avoids the impact of temperature fluctuations from a single sensor on the overall temperature control. Furthermore, by comparing the temperature value measured by the first temperature sensor in the cold storage unit when it reaches the target cold storage temperature with the data from other temperature sensors, it selects appropriate temperature sensor data as the cold storage temperature value. This effectively avoids control errors caused by improper sensor placement and improves the stability of cold storage temperature control. Through an accuracy verification step, it effectively identifies and corrects inaccurate sensors, preventing inaccurate temperature data from interfering with the cold storage unit's temperature control and ensuring the long-term stable operation of the temperature control system. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0049] Figure 1 This is a flowchart of the temperature control method for a cold storage machine provided in an embodiment of the present invention;

[0050] Figure 2 This is a flowchart illustrating the calibration process when the accuracy verification result of the temperature sensor to be verified in the temperature control method of the cold storage machine provided in this embodiment of the invention is unqualified.

[0051] Figure 3 This is a diagram showing the positional relationship between the items and the cold storage machine during refrigeration in the cold storage unit, as provided in the embodiment of the present invention. Detailed Implementation

[0052] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0053] In this application, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0054] A temperature control method for a cold storage unit, the method being applied to a plurality of cold storage units installed within a cold storage facility, each cold storage unit being equipped with a temperature sensor, and a wired controller being installed within the cold storage facility. The wired controller is used to send control commands to control the start and stop of the compressors within the cold storage units, such as... Figure 1 As shown, in a preferred embodiment of the present invention, the temperature control method includes the following steps:

[0055] S1: Set the target cold storage temperature value. The wired controller sends a refrigeration command to all cold storage units. After receiving the refrigeration command, the cold storage unit starts the compressor corresponding to it.

[0056] In a cold storage temperature control system, setting the target cold storage temperature is the crucial first step in ensuring that the cold storage environment meets storage requirements. The target cold storage temperature is set as the optimal storage temperature for the items to be stored (such as food, medicine, etc.). When the temperature control system is activated, the wired controller is responsible for issuing a cooling command, transmitting this target temperature to all cold storage units. After receiving the command, the cold storage units will start their compressors and begin the cooling process. Through the coordinated work of multiple cold storage units, the entire cold storage environment will quickly approach the set target temperature. The purpose of setting the target temperature is to ensure that all cold storage units operate under a unified target, thereby ensuring the coordination and consistency of the cold storage temperature.

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

[0058] One of the core aspects of a temperature control system is real-time temperature monitoring. Each cold storage unit 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 from multiple temperature sensors. Therefore, the data fed back by the temperature sensor of each cold storage unit directly affects the temperature control effect of the entire cold storage. By continuously acquiring and updating the temperature values ​​of the temperature sensors of each cold storage unit, the temperature control system can grasp the overall temperature status of the cold storage in real time. The principle is that by continuously collecting the temperature data of the cold storage units, the temperature control system can dynamically adjust the temperature to ensure that the temperature inside the cold storage is always at the target temperature, thereby avoiding uneven cooling or over-cooling caused by excessive temperature differences.

[0059] S3: Based on the comparison between the acquired temperature values ​​and the comparison between the temperature value measured by the temperature sensor of the first cold storage unit and the other temperature sensors when the temperature value reaches the target cold storage temperature value, select the temperature value measured by the temperature sensor of a certain cold storage unit as the current cold storage temperature value.

[0060] Due to variations in the number and location of cold storage units, temperatures may differ across different areas within the cold storage. Therefore, in large cold storage facilities, data from a single temperature sensor cannot accurately reflect the overall temperature situation. To avoid control deviations caused by errors in the temperature sensor of a single cold storage unit, it is necessary to compare the temperature sensor data from each unit to select the most suitable cold storage temperature value. Furthermore, the arrangement of items within the cold storage can affect airflow, leading to lower or higher temperatures in certain areas. The location of the cold storage units can also affect temperature uniformity; areas closer to the units are typically cooler, while areas farther away are warmer. The operating conditions of different units may also create localized temperature differences. Comparing the temperature values ​​measured by various sensors allows for a more accurate assessment of the temperature distribution within the cold storage. Only after comparing data from different sensors can the most representative temperature value be selected as the temperature reference for the entire cold storage.

[0061] Relying solely on the measurement data from a single temperature sensor to determine the temperature of the entire cold storage facility may lead to errors in temperature control, especially when there are abnormal temperature fluctuations in certain areas within the cold storage. For example: sensor malfunction: a temperature sensor may produce inaccurate readings due to malfunction or external interference; local temperature difference: the temperature in certain areas of the cold storage facility may vary significantly, and some areas may experience abnormally high or low temperatures due to special circumstances (such as the airflow direction of the air conditioner, frequent door opening and closing, etc.).

[0062] When the temperature value measured by the temperature sensor of the first cold storage unit reaches the target temperature, it needs to be compared with the data from other sensors. The purpose is to ensure that the temperature adjustment within the cold storage is coordinated. Specific reasons include: ensuring temperature uniformity: If the temperature in one 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 within the cold storage. By comparing with other sensors, it can be confirmed whether the temperature in all areas tends to be consistent, ensuring that the temperature inside the cold storage is uniform; dynamically adjusting the working status of the cold storage units: If the temperature value measured by the temperature sensor of the first cold storage unit reaches the target cold storage temperature value first, but the temperature of other cold storage units has not reached the target, this may be due to different distribution of the air conditioners. Based on this comparison, it is necessary to optimize the working arrangement of the cold storage units to avoid prematurely shutting down some cold storage units and preventing some areas from overheating.

[0063] When the temperature value measured by the first temperature sensor of the cold storage unit reaches the target cold storage temperature, the comparison with other temperature sensors includes not only temperature comparison but also spatial location comparison. The main reason for selecting which temperature value to use 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 relatively uniform temperature distribution, so their temperature values ​​should be relatively close. By selecting the temperature value of adjacent sensors, the current temperature state of the cold storage can be more accurately reflected. For sensors in non-adjacent locations, they may be located in different temperature zones within the cold storage, so their temperature values ​​may differ. In this case, the temperature value of the sensor located in the middle between the two can be selected to avoid extreme situations and ensure a more balanced overall temperature control.

[0064] S4: Based on the temperature measurement data of all temperature sensors within the first preset time period, perform a calibration operation on the abnormal temperature sensors;

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

[0066] Temperature sensors can develop measurement errors due to long-term use, location differences, installation deviations, or external environmental factors (such as humidity and air flow). These errors can cause the temperature values ​​of some cold storage units to deviate from the actual temperature, thus affecting the overall temperature control effect of the cold storage. To ensure accurate temperature control in the cold storage, these abnormal sensors need to be calibrated. By monitoring the temperature data within a first preset time period (such as the first 10 minutes after the refrigeration mode is started), it is possible to identify which temperature sensors are deviating and take corresponding corrective measures. Calibration can be accomplished by adjusting the sensor readings, ignoring abnormal data, or recalibrating the sensors. This process ensures the stability of the cold storage temperature and avoids temperature inaccuracies caused by sensor errors, 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 wired controller. After receiving the stop command, the wired controller forwards the stop command to all cold storage units, and the cold storage units shut down their corresponding compressors.

[0068] After the temperature is lowered to the set target value through cooling, unnecessary refrigeration work is stopped, thus achieving energy saving. Based on the difference between the current cold storage temperature and the target temperature, it is determined whether the set temperature value has been reached. When the cold storage temperature reaches the target value, a stop command is sent to the wired controller to shut down the compressor of the cold storage unit, thereby stopping refrigeration. The compressor stopping means that the cold storage no longer consumes additional energy, effectively preventing the cold storage unit from running excessively for extended periods. This ensures both stable cold storage temperature and effectively reduces energy consumption. Furthermore, stopping the cold storage unit reduces the load on mechanical components, extending the equipment's lifespan. Through precise temperature control and shutdown control, it is ensured that the cold storage unit neither wastes energy nor causes excessive wear and tear on the equipment.

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

[0070] When the refrigeration mode is the item refrigeration mode, the cold storage machine that is less than the preset distance from the item to be refrigerated is taken as the target cold storage machine.

[0071] If there is only one target cold storage unit, the temperature value measured by the temperature sensor of the target cold storage unit will be used as the current cold storage temperature value.

[0072] If there is more than one target cold storage unit, calculate the first average value of the temperature values ​​measured by the temperature sensors of all target cold storage units, and use the first average value 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 type 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 items to be refrigerated, rather than 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 units and their spacing to ensure that the temperature of the items reaches the required level.

[0074] In the item refrigeration mode, the cold storage unit with a distance less than a preset value from the item to be refrigerated is selected as the target cold storage unit. This is because the temperature and refrigeration capacity of each cold storage unit will affect the required distance between it and the item. If the distance between the cold storage unit and the item is less than the preset distance, it means that the cold storage unit can refrigerate the item more effectively, and therefore it is selected as the target cold storage unit. If the distance between the cold storage unit and the item is greater than the preset value, the condition for selecting the target cold storage unit is not met, and therefore it will not be considered. Regardless of whether the temperature value measured by the temperature sensor of the cold storage unit reaches the target cold storage temperature value, it will not affect the start and stop of the compressor. The preset distance can be related to the refrigeration capacity and efficiency of the cold storage unit, the type of item in the cold storage and its temperature control requirements, and the spatial layout of the cold storage units in the cold storage.

[0075] If only one cold storage unit is selected as the target cold storage unit (i.e., the number of cold storage units whose distance from the items to be refrigerated is less than the preset value is 1), then the temperature sensor measurement value of that cold storage unit will be directly used as the current temperature value of the cold storage. Since there is only one target cold storage unit, there is no need to perform complex averaging calculations. This temperature value can be regarded as the actual temperature value of the entire cold storage area. Then, when this temperature value reaches the target cold storage temperature value, the compressor will stop running.

[0076] If multiple cold storage units meet the criteria (i.e., the number of cold storage units whose distance from the items to be refrigerated is less than the preset distance is greater than 1), then it is necessary to further calculate the first average value of the temperature sensor measurements of these cold storage units. The first average value is calculated by summing the temperature values ​​of multiple target cold storage units and then dividing by the number of target cold storage units. This average value represents the temperature status of the entire cold storage area, taking into account the refrigeration effect of multiple cold storage units. By calculating the average value, the temperature situation inside the cold storage can be more comprehensively assessed, thereby making more accurate temperature adjustments.

[0077] like Figure 3 As shown, in the cold storage, item D1 is located on the left, and item D2 is located on the right. Cold storage unit 1 is located below item D1, with a distance of 0.8 meters from the bottom of item D1, which meets the preset requirement of a spacing of less than 1 meter. Cold storage unit 2 is located to the left of item D1, with a distance of 0.9 meters from the left side of item D1, which also meets the requirement. Cold storage unit 3 is located above item D1 and item D2, with a distance of 0.7 meters from both item D1 and item D2. Cold storage unit 4 is located to the right of cold storage unit 1, with a distance of 0.7 meters from both item D1 and item D2, which meets the preset spacing. Cold storage unit 5 is located in the upper right corner, with a distance of 1.2 meters from the upper right corner of item D2, which is greater than the preset distance of 1 meter, and therefore does not meet the minimum spacing requirement. Therefore, cold storage units 1, 2, 3, and 4 are selected as the target cold storage units.

[0078] Preferably, step S3 includes:

[0079] When the temperature value measured by one of the temperature sensors reaches the target cold storage temperature value, the temperature values ​​measured by the other temperature sensors are monitored in real time.

[0080] If, within the second preset time period, 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 that have measured temperature values ​​that 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 that first measured the target cold storage temperature value is selected as the current cold storage temperature value.

[0082] When two temperature sensors are not in adjacent positions, the temperature value measured by the temperature sensor that is in the middle position in space is selected as the current cold storage temperature value.

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

[0084] Within a set time window (the second preset time length), if the temperature value of another temperature sensor also reaches the target cold storage temperature, the positional relationship between the two sensors will be further analyzed. Determining the sensor positional relationship is crucial to ensuring temperature uniformity, as temperature adjustment within the cold storage depends not only on the reading of a single sensor but also on the distribution of other sensors. By determining their positions, the propagation of temperature changes and adjustment strategies can be reasonably predicted. If two temperature sensors are adjacent and both measure temperatures reaching the target cold storage temperature, the temperature value measured by the sensor adjacent to the sensor that first reaches the target temperature is selected as the current cold storage temperature. This is because temperature changes in adjacent sensors tend to be more synchronized, and selecting the temperature value of the adjacent sensor reflects the stability and trend of the current temperature within the cold storage, thus effectively controlling the temperature. Figure 3 As shown, if the temperature values ​​measured by the temperature sensors of cold storage unit 1 and cold storage unit 4 successively reach the target cold storage temperature value, then the temperature value measured by the temperature sensor of cold storage unit 2 is selected as the current cold storage temperature value.

[0085] When two temperature sensors are not adjacent, the temperature value measured by the sensor located in the middle of the two sensors is selected as the current temperature value of the cold storage. This is because non-adjacent sensors may measure significant differences in temperature changes, so using the temperature value from the sensor in the middle position can more accurately reflect the temperature condition inside the entire cold storage and avoid uneven temperature control caused by abnormal readings from individual sensors. Figure 3 If the temperature values ​​measured by the temperature sensors of cold storage unit 2 and cold storage unit 4 reach the target cold storage temperature value in sequence, then the temperature value measured by the temperature sensor of cold storage unit 1 is selected as the current cold storage temperature value.

[0086] Preferably, step S3 includes:

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

[0088] Specifically, in order to determine whether the temperature inside the cold storage is uniform, the temperature data measured by all temperature sensors are first collected, and the highest and lowest temperature values ​​are calculated. The difference between the maximum and minimum values ​​reflects the temperature distribution range inside the cold storage. If the temperature difference is large, it means that the temperature inside the cold storage is not yet uniform; while 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 between them is compared with a preset first temperature threshold. The first temperature threshold can be set according to the usage 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 and the temperature has become uniform, which 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, the temperature inside the cold storage is considered to be basically balanced. At this point, 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 from 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, then the highest temperature value is removed, and the average temperature value is calculated based on the remaining temperature values ​​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 this 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 other temperature values, which may indicate that the sensor reading is abnormal or that the temperature at that location is fluctuating drastically, not in accordance with the normal expectations of the temperature control system. To avoid this abnormal value affecting the overall temperature control of the cold storage, the highest temperature value will be removed, meaning it will no longer be used as the basis for calculating the current cold storage temperature. Subsequently, the average of the sum of the remaining measured temperature values ​​is calculated. This average can effectively prevent abnormal data from 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 changes in temperature values ​​measured by all temperature sensors within a past first preset time period;

[0095] If the temperature values ​​measured by the temperature sensors of the same cold storage unit reach the target cold storage temperature value for the first time consecutively, and the difference between the highest value and the remaining temperature values ​​among all the temperature values ​​measured by the temperature sensors is greater than the third temperature threshold, then the accuracy of the temperature sensor whose measured temperature value reaches the target cold storage temperature value for the first time consecutively is verified.

[0096] In this embodiment, the temperature data changes collected by all temperature sensors over a past period (a first preset time length) are first obtained, which helps to track historical temperature fluctuations and thus provide a basis for subsequent temperature control decisions.

[0097] If, within this time period, a temperature sensor of a certain cold storage unit reaches the target cold storage temperature value for the first time consecutively, the temperature sensor readings will be further analyzed. If, at this time, the difference between the highest temperature value 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, indicating a large temperature fluctuation. This may indicate that a sensor has malfunctioned or that the data is abnormal.

[0098] In this case, the accuracy of the temperature sensor will be verified. Specifically, the data quality of the sensor needs to be re-examined, possibly by calibrating, testing the sensor hardware, or cross-validating other relevant information to confirm that it is working properly. This can avoid temperature control instability caused by individual sensor malfunctions 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 the changes in temperature values ​​measured by all temperature sensors within the first preset time period are obtained.

[0101] The temperature value measured by the temperature sensor with the longest duration of time when the measured temperature value is the lowest among all sensors is selected as the current temperature value of the cold storage.

[0102] Specifically, analyze the temperature values ​​measured by each temperature sensor during this time period, paying particular attention to the frequency and duration of the occurrence of the "lowest temperature value". Here, the "lowest temperature value" refers to the smallest temperature value recorded by each sensor in the past time period. Since the temperature of a cold storage should generally be maintained within a specific range, and a temperature value that is too low may mean that the equipment is too cold or inefficient, it is necessary to pay special attention to the occurrence of the lowest temperature state.

[0103] The duration of time each sensor is in the "lowest temperature value" state within a given time period is statistically analyzed, and the percentage of time spent in this state is calculated. For example, the percentage of time spent in the lowest temperature value for one sensor may be 30%, while for another sensor it may be only 10%. The temperature sensor with the highest percentage of time spent in the lowest temperature state over the past time period is then selected. This temperature sensor maintains the lowest temperature state for a longer period of time. The refrigeration requirements of the cold storage can only be met when the temperature of the area with the lowest temperature over a long period reaches the target cold storage temperature. Therefore, the temperature value of the selected sensor (i.e., the sensor with the highest percentage of time spent in the lowest temperature state) 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, such as Figure 2 As shown, step S4 includes the following steps:

[0105] If the accuracy verification result of the temperature sensor to be verified is unqualified, then a calibration 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 and obtain a reference temperature curve;

[0107] S42: Compare the reference temperature curve with the current temperature curve measured by the temperature sensor to be calibrated to obtain the 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 several small intervals. 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, a verified and highly accurate reference temperature sensor is first needed to measure the temperature of the cold storage. The reference sensor needs to have high accuracy and stability and serve as an important benchmark for calibrating other temperature sensors. In the cold storage environment, the reference sensor records the temperature change curve over time, i.e., the reference temperature curve. This reference temperature curve will serve as a comparison standard to help us understand the measurement error of the sensor to be calibrated under specific conditions. The accuracy of the reference sensor can provide a value close to the actual temperature of the cold storage environment. The error of the temperature sensor to be calibrated can be identified and corrected by 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 two temperature values ​​at each moment reflects the error of the sensor to be calibrated. By comparing the two temperature curves, we can find the difference between them and thus determine whether the error is linear or nonlinear. Linear error is characterized by a relatively constant temperature difference throughout the measurement range, while nonlinear error is characterized by the temperature difference changing with the ambient temperature and not being a fixed constant.

[0112] If the comparison results indicate that the error is linear, it means that the difference between the measured value of the temperature sensor to be calibrated and the measured value of the reference sensor is a constant, or the error remains stable across the entire temperature range. This suggests that the sensor may have common offset problems, such as systematic zero-point drift or gain error. For linear errors, they are usually corrected through linear calibration operations, which adjust the output value of the temperature sensor to be calibrated to the measured value of the reference sensor using a simple mathematical model (such as addition or multiplication). Specifically, this can be done by adding or subtracting a constant (if it is an offset error) or by adjusting the output value using a scaling factor (if it is a gain error).

[0113] If the comparison results indicate that the error is nonlinear, it means that the error of the sensor to be calibrated is not merely constant, but varies with temperature. Nonlinear errors typically indicate a complex relationship between the sensor's response curve and actual temperature changes, potentially influenced by factors such as temperature range, sensor material properties, and external environmental variations. To address this type of error, the temperature curve to be calibrated must first be divided into multiple small intervals. Within each interval, the error behavior of the sensor may be relatively simple, allowing for correction using local linear correction methods. Specifically, within each interval, the correction factor can be obtained by comparing the difference between the reference temperature curve and the sensor curve to be calibrated. Then, the sensor to be calibrated is corrected according to the error characteristics of different intervals. This process can be achieved through interpolation, piecewise linear correction, etc., thereby minimizing the sensor's error across the entire temperature range.

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

[0115] T l = a × T0 + b;

[0116] Among them, T l This indicates the temperature sensor reading after performing a linear correction operation. '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 the temperature sensor, the original sensor output T0 and the known standard temperature T are used.l The relationship between them can be expressed by formula T. l The equation is expressed as a × T0 + b, where a and b are the correction coefficient and offset, respectively. The values ​​of a and b obtained through calibration experiments can convert the sensor's raw reading T0 into a more accurate temperature value T. l For example, assuming calibration yields a = 1.05 and b = -2.3, when the original sensor reading T0 is 25℃, the corrected temperature T... l For T l =1.05×25-2.3=25.2℃, indicating that the corrected temperature is 0.2℃ higher than the original reading, thus improving the measurement accuracy.

[0118] Furthermore, the temperature sensor to be calibrated is calibrated based on the values ​​of the reference temperature curve and the current temperature curve within a small interval, satisfying the following relationship:

[0119]

[0120] Among them, T corrected T represents the temperature value measured by the calibrated temperature sensor. measured T represents the temperature value measured by the temperature sensor to be calibrated. measured2 and T measured1 T represents the measured values ​​of the reference temperature sensor at the end and start points between cells, respectively. measured2 and T measured1 This indicates the measured values ​​of the temperature sensor to be calibrated at the end and start points between cells.

[0121] In this embodiment, within a small interval, the measured values ​​of the reference sensor are T. reference1 =20℃ and T reference2 =30℃, while the measured values ​​of the sensor to be calibrated are T measured1 =22℃ and T measured2 =28℃. Currently, the current measurement value of the sensor to be calibrated is T. measured =24℃. According to the calibration formula, we first calculate the ratio between the sensor to be calibrated and the reference sensor, i.e., 6 / 10 = 0.6. Then we calculate the difference between the current reading and the starting point reading of the sensor to be calibrated, and obtain T. measured -T measured1 =2℃. Finally, by multiplying this difference by the scaling factor, a correction value of 1.2℃ is obtained, thus yielding 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 references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

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

Claims

1. A temperature control method for a cold storage unit, the temperature control method being applied to a plurality of cold storage units installed in a cold storage facility, wherein each cold storage unit is equipped with a temperature sensor, and a wired controller is installed within the cold storage facility, the wired controller being used to send control commands to control the start and stop of the compressor within the cold storage unit, characterized in that, The temperature control method includes the following steps: S1: Set the target cold storage temperature value. The wired controller sends a refrigeration command to all cold storage units. After receiving the refrigeration command, the cold storage unit starts the compressor corresponding to it. S2: Continuously acquire the temperature values ​​measured by the temperature sensors on each cold storage unit; S3: Based on the comparison between the acquired temperature values ​​and the comparison between the temperature value measured by the temperature sensor of the first cold storage unit and the other temperature sensors when the temperature value reaches the target cold storage temperature value, select the temperature value measured by the temperature sensor of a certain cold storage unit as the current cold storage temperature value. S4: Based on the temperature measurement data of all temperature sensors within the first preset time period, perform a calibration operation on the abnormal temperature sensors; Among them, the temperature value measured by the abnormal temperature sensor cannot be used as the current temperature value of the cold storage. S5: When the current cold storage temperature reaches the target cold storage temperature, a stop command is sent to the wired controller. After receiving the stop command, the wired controller forwards the stop command to all cold storage units, and the cold storage units shut down their corresponding compressors.

2. The temperature control method according to claim 1, characterized in that, Step S3 includes obtaining the refrigeration mode of the cold storage; When the refrigeration mode is the item refrigeration mode, the cold storage machine that is less than the preset distance from the item to be refrigerated is taken as the target cold storage machine. If there is only one target cold storage unit, the temperature value measured by the temperature sensor of the target cold storage unit will be used as the current cold storage temperature value. If there is more than one target cold storage unit, calculate the first average value of the temperature values ​​measured by the temperature sensors of all target cold storage units, and use the first average value 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 one of the temperature sensors reaches the target cold storage temperature value, the temperature values ​​measured by the other temperature sensors are monitored in real time. If, within the second preset time period, 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 that have measured temperature values ​​that 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 that first measured the target cold storage temperature value is selected as the current cold storage temperature value. When two temperature sensors are not in adjacent positions, the temperature value measured by the temperature sensor that is in the middle position 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 and lowest temperature values ​​measured by each temperature sensor is less than the first temperature threshold, then the average value of the temperature values ​​measured by all the temperature sensors of the cold storage unit 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, then the highest temperature value is removed, and the average temperature value is calculated based on the remaining temperature values ​​as the current cold storage temperature value.

6. The temperature control method according to claim 1, characterized in that, Step S4 includes: Obtain the changes in temperature values ​​measured by all temperature sensors within a first preset time period. If the temperature values ​​measured by the temperature sensors of the same cold storage unit reach the target cold storage temperature value for the first time consecutively, and the difference between the highest value and the remaining temperature values ​​among all the temperature values ​​measured by the temperature sensors is greater than the third temperature threshold, then the accuracy of the temperature sensor whose measured temperature value reaches the target cold storage temperature value for the first time consecutively is verified.

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 the changes in temperature values ​​measured by all temperature sensors within the first preset time period are obtained. The temperature value measured by the temperature sensor with the longest duration of time when the measured temperature value is the lowest among all sensors is selected as the current temperature value of the cold storage.

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, then a calibration operation will be performed on the unqualified temperature sensor: The temperature of the cold storage was measured using a reference temperature sensor of the same model to obtain a reference temperature curve; The reference temperature curve is compared with the current temperature curve measured by the temperature sensor to be calibrated to obtain the 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 of the temperature measured by the temperature sensor to be calibrated is divided into several small intervals. The temperature sensor to be calibrated is then calibrated based on the values ​​of the reference temperature curve and the current temperature curve within the small intervals.

9. The temperature control method according to claim 8, characterized in that, Linear correction operations satisfy the following relationship: ； in, This indicates the temperature value measured by the temperature sensor to be calibrated before calibration. This indicates the temperature sensor reading after performing a linear calibration operation. This indicates the strength of the relationship between the sensor reading and the corrected output. This indicates the offset.

10. The temperature control method according to claim 8, characterized in that, The temperature sensor to be calibrated is then calibrated based on the values ​​of the reference temperature curve and the current temperature curve within a small interval, satisfying the following relationship: ； in, This indicates the temperature value measured by the calibrated temperature sensor. This indicates the temperature value measured by the temperature sensor to be calibrated. and These represent the measured values ​​of the reference temperature sensor at the end and start points between cells, respectively. and This indicates the measured values ​​of the temperature sensor to be calibrated at the end and start points between cells.

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