Refrigerator compressor operation rotating speed control method

Abstract

The invention provides a refrigerator compressor operation rotating speed control method. The method comprises the steps that a linear relation model of the compressor rotating speed and the real-time temperature difference between the current temperature and the preset target temperature is established; according to a preset compressor minimum operation rotating speed, a preset compressor maximum operation rotating speed, a detectable minimum temperature difference and a preset maximum temperature difference, a basic rotating speed and a temperature change influence coefficient are obtained through calculation; the temperature in the refrigerator is monitored in real time through a temperature sensor so as to obtain the current temperature, and the real-time temperature difference between the current temperature and the preset target temperature is calculated; substituting the real-time temperature difference into the linear relation model, and calculating to obtain an initial rotating speed value; and the initial rotating speed value is processed to obtain a final instruction rotating speed, and the final instruction rotating speed is sent to a compressor driver to control a compressor to operate, so that the problems that the rotating speed of the compressor limits improvement of the refrigerating efficiency and energy consumption is reduced are solved.

Description

Technical Field

[0001] This application relates to the field of refrigerator technology, and in particular to a method for controlling the operating speed of a refrigerator compressor. Background Technology

[0002] In refrigerator refrigeration systems, inverter compressors are widely used as core components, and their operating speed can be adjusted within a certain frequency range according to refrigeration needs. The difference between the internal temperature of the refrigerator and the set target temperature reflects the real-time refrigeration demand, which requires the compressor speed to respond flexibly to achieve efficient refrigeration and reduce energy consumption.

[0003] To achieve the above requirements, related technologies typically employ a fixed frequency drive method, that is, selecting the compressor's operating speed from several specific frequency values ​​according to preset rules. While this method can adapt to different temperature difference conditions to some extent, it only utilizes a limited number of fixed frequencies.

[0004] However, when using a fixed-frequency drive method, the compressor speed limits the improvement of refrigeration efficiency and the reduction of energy consumption, making it difficult to fully utilize the advantages of variable frequency compressors operating over a wide frequency range, thus limiting further improvements in refrigeration efficiency and further reductions in energy consumption. Summary of the Invention

[0005] This application provides a method for controlling the operating speed of a refrigerator compressor to solve the problem that the compressor speed limits the improvement of refrigeration efficiency and the reduction of energy consumption.

[0006] This application provides a method for controlling the operating speed of a refrigerator compressor, the method comprising: Establish a linear relationship model between compressor speed and the real-time temperature difference between the current temperature and the preset target temperature; Based on the preset minimum operating speed, maximum operating speed, minimum detectable temperature difference, and agreed maximum temperature difference of the compressor, the base speed and temperature change influence coefficient are calculated. The refrigerator's internal temperature is monitored in real time by a temperature sensor to obtain the current temperature, and the real-time temperature difference between the current temperature and the preset target temperature is calculated. Substituting the real-time temperature difference into the linear relationship model, the initial rotational speed value is calculated. The initial speed value is processed to obtain the final command speed, and the final command speed is sent to the compressor driver to control the compressor operation.

[0007] By establishing a linear relationship model between compressor speed and the real-time temperature difference between the current temperature and the preset target temperature, the basic speed and temperature change influence coefficient are calculated based on preset minimum and maximum compressor operating speeds, the minimum detectable temperature difference, and the agreed maximum temperature difference. A temperature sensor is used to monitor the refrigerator's internal temperature in real time to obtain the current temperature. The calculated real-time temperature difference is then input into the linear relationship model to obtain the initial speed value. After processing, the final command speed is generated and sent to the compressor driver. This method can continuously adjust the compressor speed according to the real-time temperature difference, thereby improving internal temperature fluctuations, enhancing temperature control accuracy, and helping to reduce energy consumption caused by frequent compressor start-stop cycles.

[0008] Optionally, the linear relationship model is represented as: P = P0 + K△T; Where P is the compressor speed; P0 is the base speed; K is the temperature change influence coefficient; and ΔT is the real-time temperature difference between the current temperature and the preset target temperature.

[0009] The calculation of compressor speed is transformed into a linear operation based on the established linear relationship model, which simplifies the complexity of the control algorithm, reduces the computational resource requirements, improves the response speed of the control system, and provides a direct and clear mathematical basis for the continuous and smooth adjustment of compressor speed.

[0010] Optionally, the formula for calculating the influence coefficient of temperature change is: K=(P2-P1) / (△T2-△T1); Where K is the temperature change influence coefficient; P1 is the preset minimum operating speed of the compressor; P2 is the preset maximum operating speed of the compressor; △T1 is the minimum detectable temperature difference; and △T2 is the agreed maximum temperature difference.

[0011] The formula for calculating the temperature change influence coefficient uses preset system limit parameters to directly calculate the temperature change influence coefficient, so that the compressor speed can change continuously and proportionally with the real-time temperature difference within the entire range from the minimum detectable temperature difference to the agreed maximum temperature difference. This helps to achieve dynamic matching between the compressor speed and the actual cooling demand of the refrigerator, and improves the linearity and adjustment precision of temperature control.

[0012] Optionally, the formula for calculating the basic rotational speed is: P0=(P1×△T2-P2×△T1) / (△T2-△T1); Wherein, P0 is the base speed; P1 is the preset minimum operating speed of the compressor; P2 is the preset maximum operating speed of the compressor; △T1 is the minimum detectable temperature difference; and △T2 is the agreed maximum temperature difference.

[0013] The formula for calculating the base speed correlates the compressor's minimum and maximum operating speeds with the detectable minimum temperature difference and the agreed maximum temperature difference. This makes the base speed a benchmark value that ensures the continuity and consistency of the compressor's speed regulation under the boundary conditions of the detectable minimum temperature difference and the agreed maximum temperature difference. This supports the compressor to make smooth speed transitions within the preset operating range and helps maintain the stability of the control system.

[0014] Optionally, the method further includes: if the real-time temperature difference is greater than the agreed maximum temperature difference, then substituting the agreed maximum temperature difference into the linear relationship model to calculate the initial rotational speed value.

[0015] The above method can limit the compressor speed to the upper limit determined based on the preset maximum operating speed of the compressor, thereby preventing the compressor from exceeding its preset maximum operating speed due to excessive real-time temperature difference signals. This helps to maintain the compressor operating under rated conditions and reduce the system load that may be caused by excessive speed.

[0016] Optionally, the step of processing the initial rotational speed value includes: Determine whether the initial rotational speed value is an integer; If the initial speed value is not an integer, its decimal part is discarded, and the integer part is taken as the final command speed.

[0017] By determining whether the initial speed value is an integer and discarding its decimal part when it is not an integer, and taking the integer part as the final command speed, the continuously calculated initial speed value can be adapted to the compressor driver that operates in integer steps. This allows the speed command output by the linear relationship model to be directly recognized and executed by the driver, thereby ensuring the effectiveness of the speed control command and helping to simplify the driver's command processing logic.

[0018] Optionally, the step of processing the initial rotational speed value further includes: Determine whether the initial speed value exceeds the preset maximum operating speed of the compressor; If the initial speed value exceeds the preset maximum operating speed of the compressor, then the final command speed is set to the preset maximum operating speed of the compressor.

[0019] Based on the judgment of whether the initial speed value exceeds the preset maximum operating speed of the compressor, and if it does, the maximum operating speed is set as the final command speed. This processing step can provide a certain upper limit protection for the compressor speed in the event of abnormal model calculation or excessive input parameters, and limit the compressor's operating speed to its preset safe operating range, thereby helping to maintain the operating safety of the compressor and the reliability of the system.

[0020] Optionally, the step of processing the initial rotational speed value further includes: Determine whether the initial speed value is equal to one or more specific limit values ​​within the compressor's operating speed range; If the initial speed value is equal to the specific limit value, then the final command speed is set to the adjacent permissible speed value that is less than the specific limit value and closest to the specific limit value.

[0021] Based on the judgment of whether the initial speed value is equal to one or more specific limit values ​​within the compressor's operating speed range, and when it is equal, the final command speed is set to the adjacent allowable speed value that is less than the specific limit value and closest to it. This can actively avoid specific limit speed points in the control command, thereby reducing the risk of resonance or abnormal vibration that may occur in the compressor at a specific speed, and helping to improve the smoothness of compressor operation and the durability of the overall system.

[0022] Optionally, the method is executed cyclically at preset time intervals.

[0023] By cyclically executing the method at preset time intervals, it is possible to periodically sample the internal temperature of the refrigerator and continuously adjust the compressor speed, thereby dynamically responding to changes in the internal temperature of the refrigerator, maintaining the real-time and continuous nature of temperature control, and helping to make the changes in compressor speed smoother, reducing the impact on the system caused by frequent sudden changes in control commands.

[0024] Optionally, the detectable minimum temperature difference is determined by the detection accuracy of the refrigerator temperature sensor; The agreed maximum temperature difference is a pre-set threshold value for the maximum temperature difference used to calculate the compressor speed.

[0025] The minimum detectable temperature difference is determined by the detection accuracy of the refrigerator temperature sensor, and the maximum temperature difference is agreed upon as a pre-set threshold value for the maximum temperature difference used to calculate the compressor speed. This setting method associates the effective working temperature difference range of the linear relationship model with the actual detection capability of the sensor and the preset control boundary of the system, ensuring that the speed calculation is carried out within a clear and reasonable temperature difference range from the minimum detectable temperature difference to the agreed maximum temperature difference, thereby improving the rationality of speed control and its adaptability to actual working conditions.

[0026] As can be seen from the above technical solutions, this application provides a method for controlling the operating speed of a refrigerator compressor. This method establishes a linear relationship model between the compressor speed and the real-time temperature difference between the current temperature and a preset target temperature. Based on preset minimum operating speed, maximum operating speed, minimum detectable temperature difference, and agreed maximum temperature difference, a base speed and temperature change influence coefficient are calculated. The internal temperature of the refrigerator is monitored in real-time by a temperature sensor to obtain the current temperature, and the real-time temperature difference between the current temperature and the preset target temperature is calculated. The real-time temperature difference is substituted into the linear relationship model to calculate an initial speed value. The initial speed value is processed to obtain a final command speed, and the final command speed is sent to the compressor driver to control the compressor operation, thereby solving the problem that compressor speed limits the improvement of refrigeration efficiency and the reduction of energy consumption. Attached Figure Description

[0027] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a flowchart illustrating the refrigerator compressor operating speed control method according to an embodiment of this application. Detailed Implementation

[0029] The embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described below do not represent all embodiments consistent with this application. They are merely examples of systems and methods consistent with some aspects of this application.

[0030] It should be noted that the brief descriptions of terms in this application are only for the convenience of understanding the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise stated, these terms should be understood in their ordinary and common meaning.

[0031] In some embodiments, the refrigerator includes at least one of a compressor, a condenser, a capillary tube, and an evaporator.

[0032] For example, the main function of the compressor is to increase the pressure and temperature of the refrigerant vapor, thereby establishing the necessary pressure difference in the refrigeration system and causing the refrigerant to circulate in the refrigeration system.

[0033] For example, the main function of the condenser is to release heat from the high-temperature, high-pressure refrigerant vapor and condense it into a liquid. In this process, the refrigerant vapor dissipates a large amount of heat to the outside of the refrigerator.

[0034] For example, the main function of the capillary is to limit the liquid flow rate of the refrigerant and to control the pressure difference between the condenser and the evaporator through its flow resistance.

[0035] For example, the main function of the evaporator is to rapidly boil and evaporate the liquid refrigerant under low temperature and low pressure conditions, thereby absorbing heat from inside the refrigerator and lowering the internal temperature of the refrigerator.

[0036] In refrigerator refrigeration systems, inverter compressors are widely used as core components, and their operating speed can be adjusted within a certain frequency range according to refrigeration needs. The difference between the internal temperature of the refrigerator and the set target temperature reflects the real-time refrigeration demand, which requires the compressor speed to respond flexibly to achieve efficient refrigeration and reduce energy consumption.

[0037] To achieve the above requirements, relevant embodiments typically employ a fixed frequency drive method, that is, selecting the compressor's operating speed from several specific frequency values ​​according to preset rules. While this method can adapt to different temperature difference conditions to some extent, it only utilizes a limited number of fixed frequencies. However, when using a fixed frequency drive method, the compressor's speed limits the improvement of refrigeration efficiency and the reduction of energy consumption, making it difficult to fully leverage the advantages of variable frequency compressors operating over a wide frequency range, thus limiting further improvements in refrigeration efficiency and further reductions in energy consumption.

[0038] To address the issue of compressor speed limiting refrigeration efficiency and energy consumption reduction, see [link to relevant documentation]. Figure 1 This application provides a method for controlling the operating speed of a refrigerator compressor, the method comprising: S100: Establish a linear relationship model between compressor speed and the real-time temperature difference between the current temperature and the preset target temperature.

[0039] It should be understood that the linear relationship model is not a simple linear function in one variable, but a dynamic mathematical model constructed by comprehensively considering the actual operating conditions of the refrigerator and the characteristics of the compressor. The core of this model lies in setting the compressor's target speed (usually in revolutions per minute, RPM) as a continuous function of the real-time temperature difference (usually in degrees Celsius, °C) between the current temperature and the preset target temperature. Specifically, through extensive experimental data collection and analysis, the speed value at which the compressor achieves its optimal coefficient of performance (COP) under different temperature difference values ​​is determined. For example, when the temperature difference is large (such as when the refrigerator is first started or after a large number of hot items are placed inside), the model will output a higher target speed to achieve rapid cooling and quickly reduce the temperature difference; while when the temperature difference is small (such as when approaching the target temperature), the model will output a lower target speed to maintain a small cooling capacity, avoiding frequent start-stop operations or unnecessary high-speed operation. This linear relationship allows the compressor speed to be adjusted steplessly and smoothly according to subtle changes in the temperature difference, rather than being limited to a few fixed frequency points. This maximizes the wide-range operating capability of the inverter compressor, achieving continuous optimization of cooling efficiency and effective reduction of energy consumption.

[0040] The preset target temperature range is selectable, allowing users to set it according to their actual needs. Typically, refrigerators have several built-in preset temperature settings, such as 2℃-8℃ for the refrigerator compartment and -18℃-24℃ for the freezer compartment, to meet the storage needs of different foods. Furthermore, to provide more flexible temperature control, some high-end models also support user-defined temperature settings within certain ranges. For example, the refrigerator compartment can be precisely adjusted between 1℃ and 10℃, while the freezer compartment can be fine-tuned between -15℃ and 26℃. This selectable preset target temperature range design allows the refrigerator to better adapt to different users' habits and the optimal storage temperature requirements of different foods, thereby further improving preservation effects and the user experience.

[0041] In some embodiments, the linear relationship model is represented as: P = P0 + K△T; Where P is the compressor speed; P0 is the base speed; K is the temperature change influence coefficient; and ΔT is the real-time temperature difference between the current temperature and the preset target temperature.

[0042] The calculation of compressor speed is transformed into a linear operation based on the established linear relationship model, which simplifies the complexity of the control algorithm and the computational resource requirements, improves the response speed of the control system, and provides a direct and clear mathematical basis for the continuous and smooth adjustment of compressor speed.

[0043] S200: Based on the preset minimum operating speed, maximum operating speed, minimum detectable temperature difference, and agreed maximum temperature difference of the compressor, the base speed and temperature change influence coefficient are calculated.

[0044] Specifically, the preset minimum operating speed of the compressor is denoted as the first speed, and the preset maximum operating speed of the compressor is denoted as the second speed; the minimum detectable difference between the current temperature and the preset target temperature is denoted as the first temperature difference, and the agreed maximum difference between the current temperature and the preset target temperature is denoted as the second temperature difference; the base speed is calculated using the formula for calculating the base speed based on the first speed, the second speed, the first temperature difference, and the second temperature difference. The temperature change influence coefficient is calculated using the formula for calculating the temperature change influence coefficient based on the first speed, the second speed, the first temperature difference, and the second temperature difference.

[0045] In some embodiments, the formula for calculating the base rotational speed is: P0=(P1×△T2-P2×△T1) / (△T2-△T1); Wherein, P0 is the base speed; P1 is the preset minimum operating speed of the compressor; P2 is the preset maximum operating speed of the compressor; △T1 is the minimum detectable temperature difference; and △T2 is the agreed maximum temperature difference.

[0046] The formula for calculating the base speed correlates the compressor's minimum and maximum operating speeds with the detectable minimum temperature difference and the agreed maximum temperature difference. This makes the base speed a benchmark value that ensures the continuity and consistency of the compressor's speed regulation under the boundary conditions of the detectable minimum temperature difference and the agreed maximum temperature difference. This supports the compressor to make smooth speed transitions within the preset operating range and helps maintain the stability of the control system.

[0047] In some embodiments, the formula for calculating the temperature change influence coefficient is: K=(P2-P1) / (△T2-△T1); Where K is the temperature change influence coefficient; P1 is the preset minimum operating speed of the compressor; P2 is the preset maximum operating speed of the compressor; △T1 is the minimum detectable temperature difference; and △T2 is the agreed maximum temperature difference.

[0048] The formula for calculating the temperature change influence coefficient uses preset system limit parameters to directly calculate the temperature change influence coefficient, so that the compressor speed can change continuously and proportionally with the real-time temperature difference within the entire range from the minimum detectable temperature difference to the agreed maximum temperature difference. This helps to achieve dynamic matching between the compressor speed and the actual cooling demand of the refrigerator, and improves the linearity and adjustment precision of temperature control.

[0049] S300: Monitors the internal temperature of the refrigerator in real time through a temperature sensor to obtain the current temperature and calculates the real-time temperature difference between the current temperature and the preset target temperature.

[0050] Specifically, the current temperature inside the refrigerator is first periodically detected by a temperature sensor; the detected current temperature is subtracted from the preset target temperature to obtain the real-time temperature difference; when the real-time temperature difference is greater than the agreed maximum temperature difference, the real-time temperature difference is corrected to the agreed maximum temperature difference.

[0051] S400: Substitute the real-time temperature difference into the linear relationship model to calculate the initial rotational speed value.

[0052] Specifically, the real-time temperature difference ΔT calculated and corrected in step S300 is substituted into the linear relationship model P=P0+KΔT established in step S100, where P0 is the base rotational speed calculated in step S200, and K is the temperature change influence coefficient calculated in step S200. Through the calculation of this linear model, a theoretical value of the compressor rotational speed corresponding to the current real-time temperature difference can be obtained; this theoretical value is the initial rotational speed value. This initial rotational speed value reflects the ideal rotational speed calculated according to the linear relationship model under the current temperature difference conditions, but it has not yet undergone subsequent boundary condition verification and special case handling.

[0053] S500: Process the initial speed value to obtain the final command speed, and send the final command speed to the compressor driver to control the compressor operation.

[0054] In some embodiments, the step of processing the initial rotational speed value includes: Determine whether the initial rotational speed value is an integer; If the initial speed value is not an integer, its decimal part is discarded, and the integer part is taken as the final command speed.

[0055] For example, taking a certain model of variable frequency compressor as an example, the preset minimum operating speed of the compressor is P1 = 1000 rpm, and the preset maximum operating speed is P2 = 5000 rpm; the temperature sensor detection accuracy determines ΔT1 = 0.5℃, and the agreed maximum temperature difference is ΔT2 = 10℃. Substituting into the formula, we get: temperature change influence coefficient K = (5000 - 1000) / (10 - 0.5) = 421.05, and basic speed P0 = (1000 × 10 - 5000 × 0.5) / (10 - 0.5) = 789.47. The initial speed of the compressor is: P' = 789.47 + 421.05 × ΔT. When ΔT = 3℃, we calculate P' = 2052.62, and after rounding, the compressor runs at 2052 rpm.

[0056] By determining whether the initial speed value is an integer and discarding its decimal part when it is not an integer, and taking the integer part as the final command speed, the continuously calculated initial speed value can be adapted to the compressor driver that operates in integer steps. This allows the speed command output by the linear relationship model to be directly recognized and executed by the driver, thereby ensuring the effectiveness of the speed control command and helping to simplify the driver's command processing logic.

[0057] In some embodiments, the step of processing the initial rotational speed value further includes: Determine whether the initial speed value exceeds the preset maximum operating speed of the compressor; If the initial speed value exceeds the preset maximum operating speed of the compressor, then the final command speed is set to the preset maximum operating speed of the compressor.

[0058] Based on the judgment of whether the initial speed value exceeds the preset maximum operating speed of the compressor, and if it does, the maximum operating speed is set as the final command speed. This processing step can provide a certain upper limit protection for the compressor speed in the event of abnormal model calculation or excessive input parameters, and limit the compressor's operating speed to its preset safe operating range, thereby helping to maintain the operating safety of the compressor and the reliability of the system.

[0059] In some embodiments, the step of using the integer portion as the final commanded rotational speed further includes: Determine whether the integer part exceeds the preset maximum operating speed of the compressor; If the integer part exceeds the preset maximum operating speed of the compressor, then the final command speed is set to the preset maximum operating speed of the compressor.

[0060] In some embodiments, the step of processing the initial rotational speed value further includes: Determine whether the initial speed value is equal to one or more specific limit values ​​within the compressor's operating speed range; If the initial speed value is equal to the specific limit value, then the final command speed is set to the adjacent permissible speed value that is less than the specific limit value and closest to the specific limit value.

[0061] It should be understood that specific limit values ​​typically refer to certain critical speed points within the compressor's operating speed range where continuous operation is not permitted or prolonged stationary operation needs to be avoided. These critical speed points may be determined by the compressor's mechanical structural characteristics (such as the rotor's natural frequency) or the system's operational stability requirements. When the compressor operates at these specific speeds, strong resonance may occur, leading to increased equipment vibration, increased noise, and even potential damage to components, affecting the compressor's lifespan and operational safety. Therefore, when the initial speed value calculated through the model happens to be equal to these specific limit values, the final commanded speed needs to be adjusted to avoid the compressor operating at the critical speed points. Specifically, the final commanded speed is set to be less than the specific limit value and is the allowable speed value closest to it. For example, suppose a compressor has a specific limit of 1500 rpm, and its permissible speed varies in steps, such as 1480 rpm, 1490 rpm, 1510 rpm, etc. (this is just an example; the actual step size and permissible speed need to be determined based on the specific compressor model and control strategy). Then, when the initial speed is 1500 rpm, since 1500 rpm is the specific limit, the final commanded speed should be set to 1490 rpm, which is less than 1500 rpm and the closest adjacent permissible speed value. This approach effectively avoids the compressor's resonance point or unstable region, further ensuring the smoothness and safety of compressor operation.

[0062] Based on the judgment of whether the initial speed value is equal to one or more specific limit values ​​within the compressor's operating speed range, and when it is equal, the final command speed is set to the adjacent allowable speed value that is less than the specific limit value and closest to it. This can actively avoid specific limit speed points in the control command, thereby reducing the risk of resonance or abnormal vibration that may occur in the compressor at a specific speed, and helping to improve the smoothness of compressor operation and the durability of the overall system.

[0063] By establishing a linear relationship model between compressor speed and the real-time temperature difference between the current temperature and the preset target temperature, the basic speed and temperature change influence coefficient are calculated based on preset minimum and maximum compressor operating speeds, the minimum detectable temperature difference, and the agreed maximum temperature difference. A temperature sensor is used to monitor the refrigerator's internal temperature in real time to obtain the current temperature. The calculated real-time temperature difference is then input into the linear relationship model to obtain the initial speed value. After processing, the final command speed is generated and sent to the compressor driver. This method can continuously adjust the compressor speed according to the real-time temperature difference, thereby improving internal temperature fluctuations, enhancing temperature control accuracy, and helping to reduce energy consumption caused by frequent compressor start-stop cycles.

[0064] In some embodiments, if the integer portion exceeds the preset maximum operating speed of the compressor, the method further includes: Determine whether the integer part is equal to one or more specific limit values ​​within the compressor's operating speed range; If it is equal to the specific limit value, then the final command speed is set to the adjacent permissible speed value that is less than the specific limit value and closest to the specific limit value.

[0065] In some embodiments, the method further includes: if the real-time temperature difference is greater than the agreed maximum temperature difference, then substituting the agreed maximum temperature difference into the linear relationship model to calculate the initial rotational speed value.

[0066] The above method can limit the compressor speed to the upper limit determined based on the preset maximum operating speed of the compressor, thereby preventing the compressor from exceeding its preset maximum operating speed due to excessive real-time temperature difference signals. This helps to maintain the compressor operating under rated conditions and reduce the system load that may be caused by excessive speed.

[0067] In some embodiments, the method is executed cyclically at preset time intervals.

[0068] Specifically, at preset time intervals (e.g., 30 seconds, 1 minute, etc., the specific time interval can be preset and adjusted according to the actual operating needs and control precision requirements of the refrigerator), the system will re-collect the current real-time temperature difference and other relevant parameters, and, according to the aforementioned speed calculation and limiting logic, redetermine and output the final command speed of the compressor (i.e., steps S300 to S500). This cyclic execution mechanism ensures that the compressor's operating speed can be adjusted in a timely manner according to the dynamic changes in the refrigerator's internal temperature, thereby achieving precise and dynamic control of the refrigerator's temperature, ensuring the stability of the internal temperature, and achieving energy-saving operation as much as possible while meeting cooling needs. For example, when the refrigerator door is frequently opened, causing the internal temperature to rise rapidly, the system can quickly sense the increase in temperature difference through short-interval cyclic control and promptly increase the compressor speed to enhance cooling; and when the internal temperature gradually stabilizes, the system can also reduce the speed in a timely manner through cyclic judgment to avoid unnecessary energy consumption.

[0069] In some embodiments, the detectable minimum temperature difference is determined by the detection accuracy of the refrigerator temperature sensor; the agreed maximum temperature difference is a pre-set maximum temperature difference threshold used for compressor speed calculation.

[0070] Specifically, the detection accuracy of a refrigerator temperature sensor is the smallest temperature change it can distinguish. For example, if a certain model of temperature sensor has a detection accuracy of ±0.5℃, this means that the smallest temperature difference it can reliably identify is 0.5℃. Therefore, the minimum detectable temperature difference for this refrigerator system is set to 0.5℃. When the actual temperature difference is less than this value, the sensor may not be able to accurately capture this subtle temperature fluctuation, and the system will treat it as no effective temperature change, thus avoiding misjudgments due to the sensor's own accuracy limitations and unnecessary frequent adjustments to the compressor. The agreed maximum temperature difference, on the other hand, is a key threshold set in the compressor speed calculation logic. Its purpose is to prevent the calculated target speed from exceeding the compressor's safe operating range or design capability due to an excessively large temperature difference. For example, if the maximum allowable temperature difference during normal cooling of a refrigerator is set to 10°C, when the actual temperature difference reaches or exceeds 10°C, the system will no longer use the actual temperature difference value when calculating the compressor speed. Instead, it will use the agreed maximum temperature difference (10°C) as the input parameter to ensure that the compressor always operates within a reasonable speed range, avoid overload operation of the compressor due to extreme temperature differences, thereby protecting the compressor and extending its service life.

[0071] The minimum detectable temperature difference is determined by the detection accuracy of the refrigerator temperature sensor, and the maximum temperature difference is agreed upon as a pre-set threshold value for the maximum temperature difference used to calculate the compressor speed. This setting method associates the effective working temperature difference range of the linear relationship model with the actual detection capability of the sensor and the preset control boundary of the system, ensuring that the speed calculation is carried out within a clear and reasonable temperature difference range from the minimum detectable temperature difference to the agreed maximum temperature difference, thereby improving the rationality of speed control and its adaptability to actual working conditions.

[0072] In some embodiments, the method is executed by the main controller of the refrigerator, which includes at least a microprocessor and a memory. The memory stores a computer program, and when the computer program is executed by the microprocessor, it implements the method steps described in the above embodiments.

[0073] As can be seen from the above technical solutions, the embodiments of this application provide a method for controlling the operating speed of a refrigerator compressor. This method establishes a linear relationship model between the compressor speed and the real-time temperature difference between the current temperature and a preset target temperature. Based on preset minimum operating speed, maximum operating speed, minimum detectable temperature difference, and agreed maximum temperature difference, a base speed and temperature change influence coefficient are calculated. The internal temperature of the refrigerator is monitored in real-time by a temperature sensor to obtain the current temperature, and the real-time temperature difference between the current temperature and the preset target temperature is calculated. The real-time temperature difference is substituted into the linear relationship model to calculate an initial speed value. The initial speed value is processed to obtain a final command speed, and the final command speed is sent to the compressor driver to control the compressor operation, thereby solving the problem that compressor speed limits the improvement of refrigeration efficiency and the reduction of energy consumption.

[0074] Similar parts between the embodiments provided in this application can be referred to mutually. The specific implementation methods provided above are only a few examples under the overall concept of this application and do not constitute a limitation on the scope of protection of this application. For those skilled in the art, any other implementation methods extended from the solution of this application without creative effort shall fall within the scope of protection of this application.

Claims

1. A method for controlling the operating speed of a refrigerator compressor, characterized in that, The method includes: Establish a linear relationship model between compressor speed and the real-time temperature difference between the current temperature and the preset target temperature; Based on the preset minimum operating speed, maximum operating speed, minimum detectable temperature difference, and agreed maximum temperature difference of the compressor, the base speed and temperature change influence coefficient are calculated. The refrigerator's internal temperature is monitored in real time by a temperature sensor to obtain the current temperature, and the real-time temperature difference between the current temperature and the preset target temperature is calculated. Substituting the real-time temperature difference into the linear relationship model, the initial rotational speed value is calculated. The initial speed value is processed to obtain the final command speed, and the final command speed is sent to the compressor driver to control the compressor operation.

2. The refrigerator compressor operating speed control method according to claim 1, characterized in that, The linear relationship model is expressed as follows: P = P0 + K△T; Where P is the compressor speed; P0 is the base speed; K is the temperature change influence coefficient; and ΔT is the real-time temperature difference between the current temperature and the preset target temperature.

3. The refrigerator compressor operating speed control method according to claim 2, characterized in that, The formula for calculating the influence coefficient of temperature change is: K=(P2-P1) / (△T2-△T1); Where K is the temperature change influence coefficient; P1 is the preset minimum operating speed of the compressor; P2 is the preset maximum operating speed of the compressor; △T1 is the minimum detectable temperature difference; and △T2 is the agreed maximum temperature difference.

4. The refrigerator compressor operating speed control method according to claim 2, characterized in that, The formula for calculating the basic rotational speed is: P0=(P1×△T2-P2×△T1) / (△T2-△T1); Wherein, P0 is the base speed; P1 is the preset minimum operating speed of the compressor; P2 is the preset maximum operating speed of the compressor; △T1 is the minimum detectable temperature difference; and △T2 is the agreed maximum temperature difference.

5. The refrigerator compressor operating speed control method according to claim 1, characterized in that, The method further includes: if the real-time temperature difference is greater than the agreed maximum temperature difference, then the agreed maximum temperature difference is substituted into the linear relationship model to calculate the initial rotational speed value.

6. The refrigerator compressor operating speed control method according to claim 1, characterized in that, The steps for processing the initial rotational speed value include: Determine whether the initial rotational speed value is an integer; If the initial speed value is not an integer, its decimal part is discarded, and the integer part is taken as the final command speed.

7. The refrigerator compressor operating speed control method according to claim 1, characterized in that, The step of processing the initial rotational speed value further includes: Determine whether the initial speed value exceeds the preset maximum operating speed of the compressor; If the initial speed value exceeds the preset maximum operating speed of the compressor, then the final command speed is set to the preset maximum operating speed of the compressor.

8. The refrigerator compressor operating speed control method according to claim 1, characterized in that, The step of processing the initial rotational speed value further includes: Determine whether the initial speed value is equal to one or more specific limit values ​​within the compressor's operating speed range; If the initial speed value is equal to the specific limit value, then the final command speed is set to the adjacent permissible speed value that is less than the specific limit value and closest to the specific limit value.

9. The refrigerator compressor operating speed control method according to claim 1, characterized in that, The method is executed cyclically at preset time intervals.

10. The refrigerator compressor operating speed control method according to claim 1, characterized in that, The minimum detectable temperature difference is determined by the detection accuracy of the refrigerator temperature sensor; The agreed maximum temperature difference is a pre-set threshold value for the maximum temperature difference used to calculate the compressor speed.

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