Method and device for detecting offset failure of single temperature probe and medium

Abstract

The disclosure provides a single temperature probe offset fault detection method, device and medium, wherein the single temperature probe offset fault detection device comprises a controller and a single temperature probe; the controller is in communication connection with a compressor; the controller is configured to obtain a starting temperature sampled at a starting time and an ending temperature sampled at an ending time of the single temperature probe in a current operation stage corresponding to a start-stop signal of the compressor based on the start-stop signal; and determine an offset detection result of the single temperature probe according to the starting time, the ending time, the starting temperature, the ending temperature and a stage type of the current operation stage. Through the embodiments of the disclosure, the accuracy and reliability of the offset detection result of the single temperature probe can be improved.

Description

Technical Field

[0001] This disclosure relates to the field of refrigeration equipment control technology, and in particular to a method, device and medium for detecting offset faults of a single temperature probe. Background Technology

[0002] Refrigeration equipment such as freezers and refrigerators play a vital role in industries such as food retail, catering, and healthcare. For refrigeration equipment, precise temperature control ensures the quality and safety of stored goods while optimizing energy consumption. Temperature probes are key components used to sense the temperature inside the freezer, and the accuracy of their measurements directly determines the operational efficiency and reliability of the entire refrigeration system.

[0003] Temperature probes operate in low-temperature, high-humidity environments for extended periods. Inevitably, factors such as material aging, moisture intrusion, refrigerant corrosion, or physical vibration can cause performance deviations or malfunctions, leading to inaccurate temperature control. While existing technologies utilize resistance calibration and static threshold alarm methods to detect probe deviation, these methods suffer from limitations. Resistance calibration requires probe disassembly and static threshold alarms rely on fixed detection thresholds, making real-time responses to dynamic conditions like ambient temperature fluctuations difficult. This results in detection lag, high false alarm rates, and high false negative rates. Therefore, achieving high-precision temperature probe deviation fault detection is a pressing issue. Summary of the Invention

[0004] This disclosure provides a method, apparatus, and medium for detecting offset faults in a single temperature probe; it can improve the accuracy and reliability of offset detection results for a single temperature probe.

[0005] The technical solution disclosed herein is implemented as follows:

[0006] In a first aspect, this disclosure provides a single-temperature probe offset fault detection device, including a controller and a single temperature probe; the controller is communicatively connected to a compressor; the controller is configured to acquire, based on the compressor's start-stop signal, the starting temperature sampled by the single temperature probe at the start time of the current operating phase corresponding to the start-stop signal and the ending temperature sampled at the end time; and determine the offset detection result of the single temperature probe based on the start time, end time, starting temperature, ending temperature and the phase type of the current operating phase.

[0007] Secondly, this disclosure provides a method for detecting the offset fault of a single temperature probe, comprising: based on the start-stop signal of the compressor, acquiring the starting temperature sampled at the start time and the ending temperature sampled at the end time of the current operating stage corresponding to the start-stop signal; and determining the offset detection result of the single temperature probe according to the start time, end time, starting temperature, ending temperature and the stage type of the current operating stage.

[0008] Thirdly, this disclosure provides a single-temperature probe offset fault detection device, comprising: an acquisition module configured to acquire, based on a compressor start-stop signal, the starting temperature sampled at the start time and the ending temperature sampled at the end time of the current operating phase corresponding to the start-stop signal; and a determination module configured to determine the offset detection result of the single-temperature probe based on the start time, end time, starting temperature, ending temperature and the phase type of the current operating phase.

[0009] Fourthly, this disclosure provides a computer storage medium storing executable instructions for implementing, when executed by a processor, the single-temperature probe offset fault detection method described in the second aspect above.

[0010] Fifthly, this disclosure provides a computer program product, including a computer program / instructions that, when executed by a processor, implement the steps of the above-described single-temperature probe offset fault detection method. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the composition of a refrigeration device provided in an embodiment of this disclosure.

[0012] Figure 2 This is a schematic diagram of the composition of a single-temperature probe offset fault detection device provided in an embodiment of this disclosure.

[0013] Figure 3 This is a schematic diagram of a compartment temperature change curve provided in an embodiment of the present disclosure.

[0014] Figure 4 This is a flowchart of a single temperature probe offset fault detection method provided in an embodiment of the present disclosure.

[0015] Figure 5 A flowchart illustrating the processing procedure of a single temperature probe offset fault detection method provided in this embodiment of the present disclosure.

[0016] Figure 6 This is a schematic diagram of the structure of a single temperature probe offset fault detection device provided in an embodiment of this disclosure. Detailed Implementation

[0017] To enable those skilled in the art to better understand the technical solutions in the embodiments of this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art should fall within the protection scope of this disclosure.

[0018] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0019] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0020] Furthermore, in the embodiments of this disclosure, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0021] To facilitate understanding of the technical solutions of the embodiments of this disclosure, the related technologies of the embodiments of this disclosure are described below. The following related technologies are optional solutions and can be combined with the technical solutions of the embodiments of this disclosure in any way, and they all fall within the protection scope of the embodiments of this disclosure.

[0022] The specific implementation of the embodiments of this disclosure is described below with reference to the accompanying drawings.

[0023] Figure 1 This is a schematic diagram illustrating the composition of an exemplary refrigeration device disclosed herein. The refrigeration device 100 involved in this disclosure can be a refrigerator, freezer, or other device capable of storing items in a refrigerated or frozen state. Figure 1 In the refrigeration equipment 100, there is a main body 110 having a front opening, a compartment 120 formed in the main body 110 for storing items, a door 130 for opening or closing the front opening of the main body 110, and a refrigeration system 140 for cooling the temperature inside the compartment 120.

[0024] The body 110 defines the appearance of the refrigeration device 100. Exemplarily, the body 110 includes an inner housing 112 for forming a compartment and an outer housing 114 coupled to the outside of the inner housing 112. An insulating material is filled between the inner housing 112 and the outer housing 114 to prevent cold air from leaking from the compartment 120.

[0025] For example, compartment 120 can be implemented as a refrigerator compartment for storing items in a refrigerated state, storing items at a temperature above zero degrees Celsius. For instance, in a refrigerated state, the temperature of compartment 120 can be maintained in a temperature range of approximately 1 to 5 degrees Celsius. Furthermore, compartment 120 can also be implemented as a freezer compartment for storing items in a frozen state, storing items at a temperature below zero degrees Celsius. For instance, in a frozen state, the temperature of compartment 120 can be maintained in a temperature range of approximately -13 to -20 degrees Celsius.

[0026] The compartment 120 can be opened or closed through the door 130. After the door 130 is closed, when the temperature inside the compartment 120, which is implemented as a refrigerator compartment, is higher than the temperature range corresponding to the refrigeration state, or when the temperature inside the compartment 120, which is implemented as a freezer compartment, is higher than the temperature range corresponding to the freezing state, the refrigeration system 140 will be activated to lower the temperature inside the compartment 120.

[0027] For example, the refrigeration system 140 includes a compressor 142, a condenser 144, an expansion valve 146, and an evaporator 148. Specifically, the compressor 142 and the condenser 144 may be arranged in the machine room at the lower rear of the main body 110. Figure 1 (Not shown). The expansion valve 146 and the evaporator 148 can be disposed in the pipes (not shown) inside the main body 110. Figure 1 (Not shown)

[0028] For example, in conjunction with the components included in the refrigeration system 140 described above, the refrigeration system 140 operates in the following modes during the process of reducing the temperature within the compartment 120 to a temperature range corresponding to the refrigeration or freezing state (i.e., the refrigeration process):

[0029] First, the compressor 142 compresses the low-pressure gaseous refrigerant to form a high-pressure gaseous refrigerant, and then transmits the high-pressure gaseous refrigerant to the condenser 144 through the refrigerant pipeline 135 under high pressure.

[0030] Subsequently, the high-pressure gaseous refrigerant is condensed into a high-pressure liquid refrigerant through condenser 144, and during this condensation process, the refrigerant releases latent heat. In some examples, the condenser 144 is heated by the latent heat released from the refrigerant; therefore, a condenser fan 143 can be configured to discharge the released latent heat to the external environment of the refrigeration equipment 100 to cool the condenser 144.

[0031] Next, expansion valve 146 reduces the pressure of the high-pressure liquid refrigerant, and it can also regulate the amount of refrigerant so that the refrigerant can absorb sufficient heat energy from the evaporator 148. In some examples, expansion valve 146 can be implemented as an electronic expansion valve, in which case it can be controlled by a controller (…). Figure 1Under the control of (not shown in the image) via the driver ( Figure 1 (Not shown in the image) Adjust the opening or closing state of the expansion valve 146, as well as the degree of opening (which may be referred to as the opening degree).

[0032] Finally, the evaporator 148 evaporates the depressurized liquid refrigerant, and during the evaporation process, the refrigerant absorbs latent heat from the evaporator 148 to cool the air surrounding the evaporator 148. In some examples, the refrigeration device 100 also includes an evaporator fan 149, which directs the air cooled by the evaporator 148 through the outlet 170 into the chamber 120 to lower the temperature inside the chamber 120, and returns the flowing air to the vicinity of the evaporator 148 through the return air vent 180.

[0033] The low-pressure gaseous refrigerant after evaporation returns to compressor 142, thus repeating the above refrigeration cycle. In some examples, the pressure generated by compressor 142 causes the refrigerant to circulate within refrigerant line 135 along condenser 144, expansion valve 146, and evaporator 148.

[0034] As can be seen from the above-described operation mode of the refrigeration process, the start and stop of the refrigeration process both depend on the temperature inside the compartment 120 for triggering. The temperature inside the compartment 120 is collected by a single temperature probe installed inside the compartment 120. Therefore, when the single temperature probe inside the compartment 120 is deviated, it will cause the refrigeration process to be started or stopped too early or too late, affecting the normal operation of the refrigeration equipment.

[0035] Because single-temperature probes operate in harsh environments with low temperatures, high humidity, and even corrosive media (such as minor refrigerant leaks), their physical properties change over time. Factors such as material aging, moisture intrusion, oxidation or corrosion of lead wire connections can all cause measurement deviations, resulting in "offset" faults. Offset faults mainly manifest in two forms: gradual offset, where the probe's performance deteriorates slowly over time, causing a continuous and slow increase in the deviation between the measured value and the actual temperature. For example, a small offset of ±0.5℃ per month may accumulate to a large error of ±6℃ after a year; this slow change is extremely difficult to detect by traditional alarm mechanisms. Sudden offset, where the temperature reading output by the probe changes drastically and discontinuously within a short period due to loose circuit connections, poor contact, or momentary electrical interference.

[0036] When a single temperature probe shows a positive offset (measured value higher than actual value), the controller may mistakenly interpret this as excessively high temperature inside the cabinet, causing compressor 142 to run excessively or for an extended period. This not only leads to significant energy waste but also accelerates compressor wear and shortens its lifespan. When a single temperature probe shows a negative offset (measured value lower than actual value), the controller may mistakenly interpret this as the temperature inside the cabinet having reached or fallen below the target temperature range, prematurely stopping compressor 142 or reducing its operating time. This results in an increase in the actual temperature inside the cabinet, potentially causing corrosion and spoilage of stored items, leading to significant economic losses and food safety risks. Severe malfunctions may even cause the refrigeration system 140 to completely malfunction, such as compressor 142 running continuously or continuously shutting down, severely impacting the stability and lifespan of the equipment.

[0037] To avoid the aforementioned problems, related technologies employ offline resistance verification. Professional personnel disassemble the temperature probes after the refrigeration equipment has stopped running and the cabinet has been emptied. The probes are then placed in a standard temperature environment (such as an ice-water mixture, theoretically 0°C), and their resistance is measured using a multimeter or other precision instruments. This resistance value is then compared to the temperature probe's standard resistance-temperature characteristic curve to determine if any deviation exists. However, this method requires testing when the equipment is shut down, making it unsuitable for commercial scenarios requiring long-term continuous operation. Furthermore, this static testing under standard conditions cannot reflect the performance changes of the temperature probes under real, dynamic operating conditions due to long-term error accumulation (such as gradual shifts caused by refrigerant corrosion), nor can it detect occasional sudden shift faults. Related technologies also offer the use of multiple temperature probes to periodically collect the compartment temperature during refrigeration equipment operation. The difference between the average temperature sampled by each probe and the temperature sampled by the probe under test is used to detect shift faults in the probe under test. However, this solution requiring multiple temperature probes is not suitable for low-end freezers whose core requirements are "basic refrigeration function + low cost."

[0038] In order to perform high-precision offset detection of refrigeration equipment based on a single temperature probe without stopping the machine or affecting the normal operation of the refrigeration equipment, and to make the offset detection more adaptable to the real-time operating condition changes of the refrigeration equipment 100, this disclosure provides an offset fault detection device based on a single temperature probe for realizing non-invasive online offset fault detection. Figure 2 This is a schematic diagram of a single-temperature probe offset fault detection device. Figure 2 In the single-temperature probe offset fault detection device 200, there are a single temperature probe 210 and a controller 220.

[0039] A single temperature probe can be placed at the evaporator outlet 148, or at the air outlet 170 or return air outlet 180, etc., depending on the actual application requirements and operating environment.

[0040] In some examples, controller 220 may be at least one of a microcontroller unit (MCU), a control chip, or an embedded control board. Controller 220 has communication capabilities and can access a wired or wireless network. Controller 220 is communicatively coupled to a single temperature probe 210 to receive the compartment temperature acquired by the single temperature probe. Controller 220 is also communicatively coupled to the compressor 142 of the refrigeration equipment 100 to control the operating status of the compressor 142.

[0041] Specifically, the controller 220 includes an interface 222, a memory 224, and a processor 226. The interface 222 exchanges data with the single temperature probe 210 to receive the start and end temperatures. Additionally, the interface 222 can communicate with the compressor 142 to transmit control commands to it.

[0042] The controller 220 is configured to acquire the starting temperature sampled at the start time and the ending temperature sampled at the end time of the current operating phase corresponding to the start / stop signal of the compressor 142 based on the start / stop signal of the single temperature probe 210; and determine the offset detection result of the single temperature probe 210 based on the start time, end time, starting temperature, ending temperature and the phase type of the current operating phase.

[0043] Specifically, the start / stop signals include a start signal and a stop signal. The start signal controls the compressor to begin running, and the stop signal controls the compressor to stop running. The duration between a start signal and a stop signal is the running time of the compressor in one operating phase. The start / stop signals are triggered based on the temperature inside the compartment (if the temperature is higher than the target temperature range, the start signal is triggered; if the temperature reaches or falls below the target temperature range, the stop signal is triggered).

[0044] Based on the compressor's start-up and shutdown timing logic, compartment temperature change characteristics, and whether a defrosting process has occurred, the operation phase can be divided into the startup phase, steady-state phase, and defrosting end phase, etc. The startup phase refers to the operation phase that begins when the compressor receives a startup signal for the first time after a long period of inactivity, or when the compartment temperature is significantly higher than the target temperature range. The steady-state phase refers to the operation phase that begins when the compressor receives a startup signal after the compartment temperature has fluctuated within the target temperature range, triggered by a temperature rise exceeding the upper limit of the target temperature range. The lower limit of the target temperature range is the set temperature, and the upper limit is the hysteresis temperature, which is the set temperature plus the hysteresis value (e.g., if the set temperature is 5℃ and the hysteresis value is 3℃, then the hysteresis temperature is 8℃). The defrosting end phase refers to the operation phase that begins when the compressor receives a startup signal after the refrigeration equipment has completed the defrosting process. The temperature change characteristics differ for different types of operating phases. The start-up phase is when the room temperature drops from room temperature to the set temperature (e.g., from 25°C to 5°C). The steady-state phase is when the room temperature drops from the hysteresis temperature to the set temperature (e.g., from 8°C to 5°C). The defrosting end phase is when the room temperature drops from the temperature after defrosting to the set temperature (e.g., from 15°C to 5°C).

[0045] The current operating phase refers to the compressor's operation between the most recent start signal and stop signal. The current operating phase can be one of the following: start-up phase, steady-state phase, or defrost end phase. The start time is the trigger time of the start signal, or the moment the compressor begins operation in response to the start signal; the start temperature is the compartment temperature sampled by the single temperature probe at the start time. The end time is the trigger time of the stop signal, or the moment the compressor stops operation in response to the stop signal; the end temperature is the compartment temperature sampled by the single temperature probe at the end time. The single temperature probe offset detection result includes whether the single temperature probe has an offset fault or not.

[0046] In this embodiment, the refrigeration equipment is equipped with only a single temperature probe, eliminating the need for additional redundant temperature probes or other types of sensors, thus adapting to the application scenarios of low-end freezers. The controller triggers temperature sampling based on the compressor's start / stop signal and performs offset fault detection for the current operating stage of the compressor, enabling online non-invasive detection. This allows for real-time detection without shutting down the system or affecting the normal operation of the refrigeration equipment. By combining the detection with the stage type of the current operating stage, it can adapt to the operating environment and temperature change characteristics of different stage types, avoiding interference from temperature fluctuations across different stage types. This improves the accuracy and reliability of single-temperature probe offset fault detection, reduces false alarms or missed alarms caused by differences in operating conditions, and achieves high-precision offset fault detection without increasing hardware costs and relying solely on a single temperature probe.

[0047] For example, the offset detection result is determined based on the offset between the current pulling rate of the current operating phase and the reference pulling rate of the current operating phase; the current pulling rate is generated based on the start time, end time, start temperature, and end temperature.

[0048] Specifically, the current temperature pull rate is the rate at which the compartment temperature decreases during the current operating phase. The reference temperature pull rate for the current operating phase is a benchmark value dynamically calculated based on the operating conditions and temperature change characteristics of the current operating phase. The offset is used to quantify the degree of deviation of the current temperature pull rate from the benchmark value for the current operating phase, and is a detection indicator for determining whether a single temperature probe has an offset fault.

[0049] For example, the current heating rate is calculated using the following formula (1); the offset is calculated using the following formula (2).

[0050]

[0051]

[0052] Where, difT is the current heating rate, ΔT is the temperature change during the current operating phase, T1 is the initial temperature, and T2 is the final temperature; Δt is the time change during the current operating phase, t1 is the initial time, and t2 is the final time. S This is the baseline temperature pull rate for the current operating phase.

[0053] By applying this embodiment, the detection is performed using the dynamic process quantity "heating rate" instead of the static quantity "temperature value," which better distinguishes between fluctuations in refrigeration system operating conditions (such as compressor efficiency decline and residual heat interference during defrosting) and single temperature probe offset, thereby avoiding misjudgments. By calculating the current temperature pulling rate and the reference temperature pulling rate for the current operating stage, the reference value can be dynamically adjusted according to the operating environment and temperature change characteristics of the current operating stage, avoiding false alarms and missed alarms under complex operating conditions. By calculating the offset for each current operating stage, the fault can be detected in time at the initial stage of the offset fault, thereby avoiding the serious consequences caused by the accumulation of offset and achieving early prevention of offset faults.

[0054] For example, if the offset exceeds a preset threshold, the offset detection result indicates that there is an offset fault in the single temperature probe.

[0055] Specifically, the preset threshold is the critical value of the offset amount used to determine whether a single temperature probe has an offset fault. The value of the preset threshold can be adaptively selected according to the operating environment, such as based on ambient temperature, door opening frequency, or compressor running time.

[0056] For example, the selectable range of the preset threshold value can be set to 8% to 12% according to the needs of actual applications. When the compressor runs continuously for less than 2 hours, the preset threshold value is 12%; when the compressor runs continuously for 2 to 4 hours, the preset threshold value is 10%; and when the compressor runs continuously for more than 2 hours, the preset threshold value is 8%. Since the longer the compressor runs continuously, the lower the refrigeration efficiency, the higher the system risk, and the lower the allowable error tolerance, the compressor efficiency decay gradually accumulates as the compressor runs continuously. Even a small temperature probe deviation can quickly cause a fault (such as increased energy consumption, temperature inaccuracy, etc.). Therefore, gradually reducing the preset threshold according to the increase of the compressor's continuous running time can improve detection sensitivity; while in the early stage of compressor operation, when the system state is stable, the threshold can be relaxed to reduce false alarms.

[0057] By applying this embodiment, dynamically adjusting the preset threshold value based on the compressor's operating time, a relatively lenient threshold can be used in the early stages of compressor operation to reduce false alarms caused by fluctuations in normal system conditions (such as rapid temperature changes during startup and short-term heat load disturbances), ensuring the stability and continuity of equipment operation. In the middle stages of compressor operation, a moderate threshold balances the risks of false alarms and missed detections, adapting to conditions where refrigeration efficiency begins to decline but remains within a controllable range. In the later stages of compressor operation, a stricter threshold improves detection sensitivity, enabling early warning of minor deviations in single-temperature probes, preventing serious faults such as abnormally increased energy consumption and inaccurate storage temperatures caused by probe deviation compounded by compressor efficiency decline. Ultimately, throughout the entire compressor operating cycle, it accurately distinguishes between "normal operating condition fluctuations" and "single-temperature probe deviation faults," improving the accuracy of fault detection.

[0058] For example, when the offset detection result indicates an offset fault in a single temperature probe, the controller can also be configured to issue an offset fault alarm. The offset fault alarm can be implemented as a local, real-time alarm. For instance, the alarm information can be displayed through the human-machine interface of the refrigeration equipment (such as a display screen or indicator light), such as displaying in text form "Single temperature probe shows progressive offset" or "Single temperature probe shows sudden offset," or using visual signals such as flashing red lights to indicate anomalies; audible alerts (such as intermittent alarm sounds from a buzzer) can also be used to intuitively remind on-site personnel. The offset fault alarm can also be implemented as a remote notification alarm. For instance, based on the alarm signal, a prompt message containing information such as equipment identification, alarm timestamp, operating phase type identification, and offset fault type can be generated and sent to the terminal devices (such as mobile phones or computers) of maintenance personnel via preset communication methods (such as SMS, email, IoT platform push notifications), achieving remote early warning. The alarm information can also be written to the equipment maintenance log, forming a traceable record, facilitating subsequent analysis of fault causes, optimization of detection algorithms, or assessment of equipment operating status.

[0059] For example, the baseline pull rate is generated based on the weighting coefficient, the current pull rate, and the average historical pull rate corresponding to the stage type of the current operating stage.

[0060] Specifically, the historical average heating rate is calculated as the average of the historical heating rates of all historical operating stages of the same type as the current operating stage. Assuming the current operating stage is the startup stage, the historical average heating rate is the average of the historical heating rates of multiple historical startup stages, which can be selected from the most recent 7 days. The specific calculation method for the baseline heating rate is shown in the following formula (3).

[0061]

[0062] Among them, T S This is the baseline pull-up rate for the current operating phase, in difT. n This represents the current heating rate, where n is a positive integer greater than 0, and K is a weighting coefficient. It is the historical average rate of warming.

[0063] By applying this embodiment, the baseline heating rate is calculated based on the weighting coefficient, the current heating rate, and the average historical heating rate corresponding to the current operating stage type. This allows the current heating rate to reflect the real-time operating status of the refrigeration system, while also introducing the statistical characteristics of long-term operating conditions through the average heating rate of the same type of historical operating stage. Furthermore, the weighting coefficient K is used to balance real-time performance and historical stability, thereby enabling the baseline heating rate to adapt to different operating conditions.

[0064] For example, the weighting coefficient is determined based on the operating status parameters of a preset number of historical operating stages prior to the current operating stage.

[0065] Specifically, the preset quantity can be two or more, depending on the actual application requirements; this disclosure does not impose any limitation on this. Operating status parameters reflect the operating environment of the refrigeration equipment at various operating stages. By analyzing the operating status parameters from multiple historical operating stages, it is possible to determine whether the operating environment is stable. When the operating environment is stable, the weighting coefficient K can be appropriately reduced; when the operating environment is unstable, the weighting coefficient K can be appropriately increased.

[0066] For example, assuming that the historical operating stages of the refrigeration equipment include the start-up stage, steady-state stage 1, steady-state stage 2, steady-state stage 3, defrost end stage, and steady-state stage 4, and the current operating stage is steady-state stage 5, then the weighting coefficient of the current operating stage can be determined based on the operating state parameters of steady-state stage 3, defrost end stage, and steady-state stage 4; the reference temperature pulling rate of the current operating stage can be determined based on the current temperature pulling rate, the weighting coefficient, and the average historical temperature pulling rate of steady-state stages 1 to 4.

[0067] By applying this embodiment, the weighting coefficients are dynamically adjusted based on the operating status parameters of a preset number of historical operating stages prior to the current operating stage. When the operating condition stability is high, the weighting ratio of the average historical heating rate is increased, making the benchmark value more stable. When the operating status parameters of the historical operating stages reflect significant fluctuations in the system's operating conditions or performance changes, the weighting ratio of the current heating rate is increased, making the benchmark value more reflective of the real-time operating conditions. This accurately balances "historical statistical stability" and "real-time performance of the current operating conditions," significantly improving the accuracy of single-temperature probe offset detection. It can effectively avoid false alarms or missed detections caused by dynamic changes in operating conditions, and improve detection sensitivity.

[0068] For example, the operating status parameters include at least one of the following: the offset between the pull-up rate of the historical operating phase and the reference pull-up rate of the historical operating phase, the compressor operating time during the historical operating phase, and the refrigerant pressure fluctuation coefficient of the historical operating phase.

[0069] Specifically, the compressor's runtime is the duration between the start and end of a historical operating phase. The refrigerant pressure fluctuation coefficient reflects the magnitude of the refrigerant pressure fluctuation relative to the average pressure of a single operating phase.

[0070] For example, if any one of the following three conditions is met: the offset of multiple consecutive (e.g., 3) historical operating phases preceding the current operating phase all exceed a set offset (e.g., 5%), the compressor's operating time in multiple consecutive (e.g., 3) historical operating phases preceding the current operating phase all exceeds a set duration (e.g., 4 hours), or the refrigerant pressure fluctuation coefficient in multiple consecutive (e.g., 2) historical operating phases preceding the current operating phase all exceeds a set fluctuation value (e.g., 5%), then the weighting coefficient can be increased (e.g., from the default value of 0.2 to 0.3). If none of the above conditions are met, or if the refrigerant pressure fluctuation coefficient returns to below the set fluctuation value after a complete operating phase, then the weighting coefficient remains at its default value, or is adjusted back to its default value from the increased value.

[0071] For example, the deviation between the pull-up rate and the reference pull-up rate can reflect the real-time changes in refrigeration efficiency. When the pull-up rate exceeds the reference pull-up rate by 5% for three consecutive operating phases, it indicates that this is not an occasional short-term fluctuation, but is likely due to continuous disturbance to the refrigeration system, such as minor refrigerant leakage or increased dust accumulation on the condenser. If the default weighting factor (0.2) is maintained at this time, the reference pull-up rate tends to rely more on the historical rate average, making it difficult to quickly respond to continuous subtle changes. If the weighting factor is increased to 0.3, the proportion of the current pull-up rate in the calculation of the reference pull-up rate can be enhanced, and the reference pull-up rate can respond to the changing trend of refrigeration efficiency in a timely manner, thereby detecting the fault in the early stage of the deviation fault.

[0072] The compressor's operating time is closely related to the decline in its efficiency. When the compressor runs for more than 4 hours in three consecutive operating phases, it indicates that the compressor is operating under high load. Prolonged high-load operation increases internal wear and tear on the compressor, reduces heat dissipation efficiency, and causes a gradual decline in compressor efficiency. If the weighting coefficient remains at 0.2, the baseline temperature pull-up rate relies more on the historical average rate, failing to reflect changes in compressor efficiency in a timely manner. Increasing the weighting coefficient to 0.3 allows the baseline temperature pull-up rate to more sensitively capture changes in the temperature pull-up rate caused by compressor efficiency decline, enabling the baseline value to dynamically adjust downwards along with the compressor's performance decline, thereby avoiding false alarms and missed alarms.

[0073] Because the speed of a fixed-frequency compressor is constant, the high-pressure side pressure is usually determined by the refrigerant state and the system's sealing performance. Therefore, the pressure is stable during normal compressor operation, and pressure fluctuations originate only from minor load changes and are negligible. However, when the pressure fluctuation exceeds 5% and is continuous, it must be caused by a system anomaly (such as bearing wear or refrigerant leakage). Increasing the weighting factor to 0.3 allows the reference temperature rise rate to more sensitively detect changes in the temperature rise rate caused by refrigerant pressure fluctuations, avoiding false alarms.

[0074] By incorporating multi-dimensional operating status parameters such as temperature pull rate deviation, compressor runtime, and refrigerant pressure fluctuation coefficient from historical operating phases into the adjustment logic of weighting coefficients, this embodiment can dynamically and comprehensively reflect the historical operating characteristics of the refrigeration system. Adaptively adjusting or retracting the weighting coefficients based on these parameters can avoid false alarms caused by short-term normal fluctuations in the system leading to single-temperature probe deviations. Furthermore, it can sensitively detect minute deviations of the single-temperature probe when operating conditions change, such as compressor efficiency decline or refrigerant system anomalies. This enables fault prevention in the early stages of deviation faults, improving the accuracy and robustness of single-temperature probe deviation fault detection.

[0075] For example, the refrigerant pressure fluctuation coefficient is generated based on the pressure values ​​at multiple sampling times during the historical operation phase.

[0076] Specifically, the pressure sensor periodically samples the pressure of the refrigerant circulating in the refrigeration system during each stage of compressor operation. The sampling frequency can be set to 0.1Hz (i.e., once every 10 seconds). The formula for calculating the refrigerant pressure fluctuation coefficient is shown in formula (4) below.

[0077]

[0078] Among them, P δ P represents the refrigerant pressure fluctuation coefficient. i This represents the pressure value corresponding to the i-th sampling time. The value of i is in the range of 1≤i≤n, and n represents the number of sampling times. n is a positive integer greater than or equal to 2. This represents the average pressure value throughout the entire operation phase, i.e. .

[0079] By periodically sampling the refrigerant pressure value during each operating stage of the compressor, the inherent operational stability of the refrigeration system can be captured in real time. Based on the refrigerant pressure fluctuation coefficient generated by this sampling, system anomalies in historical operating stages can be accurately determined, providing a reliable basis for dynamic adjustment of the weighting coefficient and reducing false alarms and missed alarms of single temperature probe offset faults.

[0080] For example, the stage type is determined based on the starting temperature and the ending temperature.

[0081] Figure 3 This is a schematic diagram of a compartment temperature change curve provided in an embodiment of this disclosure. Figure 3 As shown, the X-axis represents time, and the Y-axis represents temperature. The curve reflects the temperature change of the compartment during each cooling stage. a, b1, b2, and c are the four operating stages of the compressor, where a is the start-up stage, b1 and b2 are the steady-state stages, and c is the defrosting end stage. c0 is the defrosting stage.

[0082] like Figure 3 As shown in Figure a, the startup phase begins when the refrigeration equipment is powered on and ends when the room temperature first reaches the set temperature. The starting temperature for this phase is T. initial This is a temperature value close to room temperature (e.g., 25℃), and the final temperature is T. SP That is, setting the temperature (e.g., 5℃).

[0083] like Figure 3 As shown in b1 and b2, the steady-state phase begins when the temperature in the compartment increases to T. Dif+SP The process begins and ends when the room temperature drops to the set temperature. Where T... Dif+SP It is the hysteresis temperature (e.g., 5℃ + 3℃ = 8℃), T Dif+SP The parameter "Dif" in the text represents the hysteresis value (e.g., 3°C).

[0084] like Figure 3 As shown in Figure c, the defrosting end stage begins at the end of the defrosting stage and ends when the room temperature drops to the set temperature. The starting temperature of this stage is the room temperature corresponding to the end of the defrosting stage, which is usually higher than the target temperature range but lower than room temperature (e.g., 15°C).

[0085] Between the start-up phase and the steady-state phase, or between two steady-state phases, the compressor stops because the compartment temperature reaches the set temperature, and the temperature naturally recovers. For example... Figure 3 As shown in c0, the defrosting stage occurs because the refrigeration equipment has been operating for a long time, and there is a risk of frost forming on the evaporator in the compartment. Therefore, the refrigeration equipment enters the defrosting state. At this time, the compressor needs to be turned off, and an electric heater is used to heat the evaporator to defrost it. During the defrosting stage, the compartment temperature rises.

[0086] Based on this, the stage type of the current operating phase can be determined according to the starting and ending temperatures. For example, if the starting temperature is close to room temperature and the ending temperature is close to the set temperature, the current operating phase is the start-up phase; if the starting temperature is higher than the hysteresis temperature and the ending temperature is close to the set temperature, the current operating phase is the steady-state phase. Alternatively, the operating sequence of the refrigeration equipment can be considered in determining the stage type. For example, if the refrigeration equipment is powered on for the first time and the room temperature is lowered from room temperature to the set temperature for the first time, the current operating phase is the start-up phase; if the refrigeration equipment has just completed defrosting and the room temperature is lowered from the defrosting end temperature to the set temperature, the current operating phase is the defrosting end phase.

[0087] By applying this embodiment, the stage type of the current operation phase can be determined by the starting temperature and the ending temperature. This allows for accurate differentiation of the temperature change characteristics of different operation phases, ensuring that when calculating the average historical pull-up rate, only historical data consistent with the current stage type is included. This provides a comparable historical reference for the benchmark pull-up rate, reduces the distortion of the benchmark value caused by stage type confusion, and improves the accuracy of single temperature probe offset fault detection.

[0088] Figure 4 This is a flowchart illustrating a method for detecting offset faults in a single temperature probe, as provided in an embodiment of this disclosure. Specifically, it includes the following steps S402-S404.

[0089] Step S402: Based on the compressor start / stop signal, obtain the starting temperature sampled at the start time and the ending temperature sampled at the end time of the current operating stage corresponding to the start / stop signal by a single temperature probe;

[0090] Step S404: Determine the offset detection result of a single temperature probe based on the start time, end time, start temperature, end temperature, and the stage type of the current operating stage.

[0091] The specific implementation methods for steps S402-S404 can be referred to the specific implementation methods of the refrigeration equipment described above, and will not be repeated here.

[0092] This embodiment uses the compressor's start / stop signal to sample the temperature during the current operating phase, enabling real-time detection without shutting down the refrigeration equipment or affecting its normal operation, thus achieving online non-invasive detection. By combining the detection with the phase type of the current operating phase, it can adapt to the working environment and temperature change characteristics of different phase types, avoiding interference from temperature fluctuations across different phase types. This improves the accuracy and reliability of single-temperature probe offset fault detection, reduces false alarms or missed alarms caused by differences in working conditions, and achieves high-precision offset fault detection without increasing hardware costs and relying solely on a single temperature probe, making it better suited for low-end freezer application scenarios.

[0093] Figure 5 This is a flowchart illustrating the processing steps of a single temperature probe offset fault detection method provided in this embodiment of the disclosure. Specifically, it includes the following steps S502 to S510.

[0094] Step S502: Based on the compressor start / stop signal, obtain the starting temperature sampled at the start time and the ending temperature sampled at the end time of the current operating phase corresponding to the start / stop signal by a single temperature probe.

[0095] By sampling the temperature based on the compressor start-stop signal, it is possible to ensure that the temperature pull-up rate calculation of the current operating stage matches the actual operating cycle of the compressor, avoiding interference from invalid data during non-operating stages, and providing an accurate staged data foundation for subsequent analysis.

[0096] Step S504: Generate the current temperature pulling rate for the current operating stage based on the start time, end time, start temperature, and end temperature.

[0097] Step S506: Determine the weighting coefficient corresponding to the current operating stage, and generate the benchmark heating rate for the current operating stage based on the weighting coefficient, the current heating rate, and the average historical heating rate of the same type of historical operating stages.

[0098] By balancing the current heating rate with the historical average of the same type using weighting coefficients, the system considers both the immediate characteristics of real-time operating conditions and the statistical patterns of historical data, making the benchmark heating rate more consistent with the current operating state. This makes it more suitable for dynamic changes such as system aging and environmental fluctuations during the actual operation of refrigeration equipment.

[0099] Step S508: Determine the preset threshold corresponding to the current operating stage, and calculate the offset between the current temperature pulling rate and the reference temperature pulling rate.

[0100] Step S510: If the offset exceeds the preset threshold, the offset detection result indicates that there is an offset fault in the single temperature probe, triggering a fault alarm.

[0101] By using preset thresholds corresponding to the current operating stage to determine the offset fault, it can effectively distinguish between normal operating condition fluctuations and probe offset faults. This allows it to tolerate larger temperature rise rate fluctuations during the startup and defrosting phases to reduce false alarms, and capture minute offsets during the steady-state phase, thus achieving early prevention of gradual offsets and timely alarms for sudden offsets.

[0102] See Figure 6 , Figure 6 This is a schematic diagram of a single-temperature probe offset fault detection device provided in an embodiment of this disclosure. The single-temperature probe offset fault detection device 600 of this embodiment includes the following modules:

[0103] Acquisition module 602: is configured to acquire the starting temperature sampled at the start time and the ending temperature sampled at the end time of the current operating phase corresponding to the start / stop signal of the compressor based on the compressor start / stop signal.

[0104] Determine module 604: is configured to determine the offset detection result of a single temperature probe based on the start time, end time, start temperature, end temperature, and stage type of the current operating stage.

[0105] The single-temperature probe offset fault detection device of this disclosure is used to implement the corresponding single-temperature probe offset fault detection method in the foregoing embodiments, and has the beneficial effects of the corresponding method embodiments, which will not be repeated here. Furthermore, the functional implementation of each module in the single-temperature probe offset fault detection device of this disclosure can be referred to the description of the corresponding part in the foregoing method embodiments, which will also not be repeated here.

[0106] This disclosure also provides a computer storage medium storing one or more programs that can be executed by one or more processors to implement the steps of the single temperature probe offset fault detection method described above.

[0107] It should be noted that the descriptions of the storage medium and device embodiments above are similar to those of the method embodiments above, and have similar beneficial effects. For technical details not disclosed in the storage medium and device embodiments of this disclosure, please refer to the descriptions of the method embodiments of this disclosure for understanding.

[0108] This disclosure also provides a computer program, including computer-readable code, wherein, when the computer-readable code is executed in a computing device, a processor in the computing device performs some or all of the steps in the above-described method for detecting offset faults of a single temperature probe.

[0109] This disclosure also provides a computer program product, comprising a non-transitory computer-readable storage medium storing a computer program, which, when read and executed by a computer, implements some or all of the steps in the above-described single-temperature probe offset fault detection method. This computer program product can be implemented specifically through hardware, software, or a combination thereof. In some embodiments, the computer program product is specifically embodied as a computer storage medium; in other embodiments, the computer program product is specifically embodied as a software product, such as a software development kit (SDK), etc.

[0110] It should be noted that the descriptions of the various embodiments above tend to emphasize the differences between them, while their similarities or commonalities can be referred to interchangeably. The descriptions of the computer program and computer program product embodiments above are similar to the descriptions of the method embodiments above, and have similar beneficial effects. For technical details not disclosed in the computer program and computer program product embodiments of this disclosure, please refer to the descriptions of the method embodiments of this disclosure for understanding.

[0111] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover 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. Unless otherwise specified, 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 that element.

[0112] In the several embodiments provided in this disclosure, it should be understood that the disclosed devices and methods can be implemented in other ways. The embodiments described above are merely illustrative. For example, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple modules or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or modules can be electrical, mechanical, or other forms.

[0113] The modules described above as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules. They may be located in one place or distributed across multiple network units. Some or all of the modules may be selected to achieve the purpose of this embodiment according to actual needs.

[0114] In addition, each functional module in the various embodiments of this disclosure can be integrated into one processing unit, or each module can be a separate unit, or two or more modules can be integrated into one unit; the integrated modules can be implemented in hardware or in the form of hardware plus software functional units.

[0115] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various media that can store program code, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0116] Those skilled in the art will recognize that the functions described in this disclosure in one or more of the examples above can be implemented using hardware, software, firmware, or any combination thereof. When implemented in software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transfer of a computer program from one place to another. Storage media can be any available medium accessible to a general-purpose or special-purpose computer.

[0117] It should be noted that the technical solutions described in this disclosure can be combined arbitrarily as long as they do not conflict.

[0118] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A single temperature probe offset fault detection apparatus, characterized by, The controller is in communication connection with the compressor; The controller is configured to obtain a starting temperature sampled at a starting time and an ending temperature sampled at an ending time of the single temperature probe in a current running stage corresponding to a start-stop signal of the compressor based on the start-stop signal; A current pull temperature rate of the current running stage is generated according to the starting time, the ending time, the starting temperature and the ending temperature; An offset detection result of the single temperature probe is determined according to an offset between the current pull temperature rate and a reference pull temperature rate of the current running stage; The reference pull temperature rate is generated according to a weight coefficient, the current pull temperature rate and a historical pull temperature rate mean corresponding to a stage type of the current running stage; The weight coefficient is determined according to running state parameters of a preset number of historical running stages before the current running stage; The running state parameters include at least one of an offset between a pull temperature rate of the historical running stage and a reference pull temperature rate of the historical running stage, a running time length of the compressor in the historical running stage and a refrigerant pressure fluctuation coefficient of the historical running stage.

2. The single temperature probe offset fault detection apparatus of claim 1, wherein, In a case where the offset exceeds a preset threshold, the offset detection result indicates that the single temperature probe has an offset fault.

3. The single temperature probe offset fault detection apparatus of claim 1, wherein, The refrigerant pressure fluctuation coefficient is generated according to pressure values at multiple sampling times in the historical running stage.

4. Offset fault detection apparatus for a single temperature probe according to any one of claims 1 to 3, characterised in that, The stage type is determined according to the starting temperature and the ending temperature.

5. A method for detecting an offset fault of a single temperature probe, characterized by, The method comprises: Obtaining a starting temperature sampled at a starting time and an ending temperature sampled at an ending time of a single temperature probe in a current running stage corresponding to a start-stop signal of a compressor based on the start-stop signal; A current pull temperature rate of the current running stage is generated according to the starting time, the ending time, the starting temperature and the ending temperature; An offset detection result of the single temperature probe is determined according to an offset between the current pull temperature rate and a reference pull temperature rate of the current running stage; The reference pull temperature rate is generated according to a weight coefficient, the current pull temperature rate and a historical pull temperature rate mean corresponding to a stage type of the current running stage; The weight coefficient is determined according to running state parameters of a preset number of historical running stages before the current running stage; The running state parameters include at least one of an offset between a pull temperature rate of the historical running stage and a reference pull temperature rate of the historical running stage, a running time length of the compressor in the historical running stage and a refrigerant pressure fluctuation coefficient of the historical running stage.

6. A computer-readable storage medium, characterized in that, The executable instructions stored in the memory are used to implement the offset fault detection method of the single temperature probe when executed by the processor.

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