Determination method for defrosting cycle of frequency conversion refrigerator

Abstract

The invention provides a method for determining the defrosting period of a variable-frequency refrigerator. The method comprises the steps that refrigerator operation parameters are obtained; the refrigerator operation parameters comprise operation time of a compressor under different frequencies, the rotating speed of the compressor and door opening time of a refrigerator door body; on the basis of the rotating speed of the compressor, the running time of the compressor under different frequencies is corrected, and a compressor running time correction value is obtained; correcting the door opening time of the refrigerator door body to obtain a refrigerator door opening time correction value; based on the compressor operation time correction value and the refrigerator door opening time correction value, the frosting duration of an evaporator is obtained; and when the frosting duration of the evaporator is longer than or equal to the first preset time and after the compressor stops running, defrosting operation is executed, so that the problems that the refrigerating efficiency of the refrigerator is reduced and the energy consumption of the refrigerator is improved due to the fact that the defrosting operation cannot be flexibly carried out according to the running condition of the compressor in an existing frequency conversion refrigerator are solved.

Description

Technical Field

[0001] The present application relates to the technical field of refrigeration equipment, and in particular to a method for determining a defrosting cycle of a variable frequency refrigerator. Background Art

[0002] Air-cooled refrigerators are also called frost-free refrigerators. After the refrigerator has been running for a period of time, the thickness of the frost layer on the evaporator will increase, which will affect the refrigeration effect. Therefore, it is usually necessary to design an automatic defrosting function. How to accurately determine when to start defrosting is one of the key technologies for air-cooled frequency conversion to achieve energy saving and refrigeration reliability.

[0003] Currently, a preset fixed time is used to determine whether a defrosting operation is required. For example, when a refrigerator is working, a timer is used to record the cumulative running time of the refrigerator compressor. When the cumulative running time of the refrigerator compressor is greater than or equal to the preset fixed time, the refrigerator performs a defrosting operation, and then the timer is reset to start recording the cumulative running time of the refrigerator compressor again. The refrigerator is defrosted by timing.

[0004] However, during the operation of the inverter refrigerator, it is difficult for the inverter refrigerator compressor to operate at a stable frequency during the interval between two defrosting operations, and the preset fixed time cannot be adjusted according to the operating frequency of the compressor, which will result in the compressor operating at a lower frequency for a longer period of time during the preset fixed time, and the defrosting operation will be performed when the amount of frost on the evaporator is small, which wastes energy; if the compressor operates at a higher frequency for a longer period of time during the preset fixed time, the defrosting operation will be performed only when the amount of frost on the evaporator is large, which affects the refrigeration efficiency of the inverter refrigerator. The inability to flexibly perform defrosting operations according to the operating conditions of the compressor in the inverter refrigerator reduces the refrigeration efficiency of the refrigerator and increases the energy consumption of the refrigerator. Summary of the invention

[0005] The present application provides a method for determining the defrost cycle of a variable frequency refrigerator to solve the technical problem that the existing variable frequency refrigerator cannot flexibly perform defrost operation according to the operation status of the compressor, resulting in reduced refrigeration efficiency and increased energy consumption of the refrigerator.

[0006] The present application provides a method for determining a defrost cycle of a variable frequency refrigerator, comprising:

[0007] Obtain refrigerator operating parameters; the refrigerator operating parameters include: compressor operating time at different frequencies, compressor speed, and refrigerator door opening time;

[0008] Based on the compressor speed, correcting the running time of the compressor at different frequencies to obtain a compressor running time correction value;

[0009] Correcting the refrigerator door opening time to obtain a refrigerator door opening time correction value;

[0010] Based on the compressor running time correction value and the refrigerator door opening time correction value, obtaining the evaporator frosting time;

[0011] When the frosting time of the evaporator is greater than or equal to the first preset time, the defrosting operation is performed after the compressor stops running.

[0012] In some embodiments, the step of correcting the operating time of the compressor at different frequencies based on the compressor speed to obtain a compressor operating time correction value includes:

[0013] Based on the compressor speed, a speed correction coefficient is obtained; the speed correction coefficient is determined by the following formula:

[0014] k = P ÷ n;

[0015] Where, k is the speed correction coefficient; P is the compressor speed; n is the compressor speed setting reference value;

[0016] Based on the correction coefficient and the running time of the compressor at different frequencies, a compressor running time correction value is obtained; the compressor running time correction value is determined by the following formula:

[0017] t y =P×t n ;

[0018] Where, t y is the compressor running time correction value; t n is the running time of the compressor at different frequencies.

[0019] In some embodiments, the step of correcting the refrigerator door opening time to obtain a refrigerator door opening time correction value includes:

[0020] Determine the door opening time correction factor;

[0021] Based on the refrigerator door opening time and the door opening time correction coefficient, a refrigerator door opening time correction value is obtained; the refrigerator door opening time correction value is determined by the following formula:

[0022] t m =a×t1÷60;

[0023] Where, t m is the refrigerator door opening time correction value; a is the door opening time correction coefficient; t1 is the refrigerator door opening time.

[0024] In some embodiments, the evaporator frosting duration is determined by the following formula:

[0025] t e =ty +t m ;

[0026] In the formula, t e It is the duration of evaporator frosting.

[0027] In some embodiments, when the evaporator is frosted for a period of time greater than or equal to a first preset time, after the compressor stops running, the step of performing a defrosting operation includes:

[0028] When the evaporator is frosted for a period of time greater than or equal to a first preset time, determining whether the compressor operation time is greater than a second preset time; the second preset time is greater than the first preset time;

[0029] If yes, the compressor is controlled to stop running and the defrost operation is performed.

[0030] In some embodiments, the refrigerator operation parameters further include: a first temperature value and a second temperature value of the evaporator when the refrigerator compartment and the freezer compartment stop refrigerating;

[0031] The method further comprises:

[0032] Obtaining the real-time temperature value of the evaporator after the third preset time after the defrost operation;

[0033] Based on the first temperature value and the second temperature value, obtaining a first temperature reference value and a second temperature reference value;

[0034] When the refrigerating chamber is in a refrigerating state, if the real-time temperature value is less than or equal to the first temperature reference value, the compressor is controlled to stop running and a defrosting operation is performed;

[0035] When the freezing chamber is in a refrigeration state, if the real-time temperature value is less than or equal to the second temperature reference value, the compressor is controlled to stop running and a defrosting operation is performed.

[0036] In some embodiments, the step of obtaining a first temperature reference value and a second temperature reference value based on the first temperature value and the second temperature value comprises:

[0037] Determine the temperature correction factor;

[0038] Obtaining a first temperature reference value and a second temperature reference value based on the first temperature value and the second temperature value according to the temperature correction coefficient;

[0039] The first temperature reference value is determined by the following formula:

[0040] T1=T ce -ΔT;

[0041] Where, T1 is the first temperature reference value; Tce is the first temperature value; ΔT is the temperature correction coefficient;

[0042] The second temperature reference value is determined by the following formula:

[0043] T2=T de -ΔT;

[0044] Where, T2 is the second temperature reference value; T de is the second temperature value.

[0045] In some embodiments, after the step of obtaining the real-time value of the temperature of the evaporator after the third preset time after the defrost operation, the method further includes:

[0046] If the refrigerator is in a refrigeration state after the first defrosting operation, and the refrigerating chamber and the freezing chamber are in a refrigeration state after the third preset time, the first temperature value and the second temperature value are determined as the first preset value and the second preset value;

[0047] Based on the first preset value and the second preset value, obtaining a first temperature reference value and a second temperature reference value;

[0048] If the real-time temperature value is less than or equal to the first temperature reference value, and the duration is greater than or equal to a fourth preset time, the compressor is controlled to stop running and a defrosting operation is performed;

[0049] If the real-time temperature value is less than or equal to the second temperature reference value, and the duration is greater than or equal to a fourth preset time, the compressor is controlled to stop running and a defrosting operation is performed.

[0050] In some embodiments, the method further comprises:

[0051] If the refrigerator is in the refrigeration state for a time greater than a fifth preset time, the compressor is controlled to stop running and a defrost operation is performed; the fifth preset time is greater than the first preset time, the second preset time, the third preset time, and the fourth preset time.

[0052] In some embodiments, before the step of obtaining refrigerator operating parameters, the step includes:

[0053] If the refrigerator is powered on for the first time, the step of obtaining refrigerator operating parameters is performed after the refrigerator is powered on for a sixth preset time.

[0054] The present application provides a method for determining the defrost cycle of a variable frequency refrigerator, comprising: obtaining refrigerator operating parameters; the refrigerator operating parameters comprising: the operating time of the compressor at different frequencies, the compressor speed, and the refrigerator door opening time; based on the compressor speed, correcting the operating time of the compressor at different frequencies to obtain a compressor operating time correction value; correcting the refrigerator door opening time to obtain a refrigerator door opening time correction value; based on the compressor operating time correction value and the refrigerator door opening time correction value, obtaining an evaporator frosting time; when the evaporator frosting time is greater than or equal to a first preset time, after the compressor stops running, performing a defrosting operation, so that the variable frequency refrigerator can flexibly perform a defrosting operation according to the operating conditions of the compressor, thereby improving the refrigerator's refrigeration efficiency and reducing the refrigerator's energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0056] Figure 1 This is a flow chart of the method for determining the defrost cycle of a variable frequency refrigerator in this application. DETAILED DESCRIPTION

[0057] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application.

[0058] Since in some technologies, the variable frequency refrigerator cannot flexibly perform defrosting operation according to the operation status of the compressor, which reduces the refrigeration efficiency of the refrigerator and increases the energy consumption of the refrigerator. In order to solve this technical problem, the present application provides a method for determining the defrosting cycle of a variable frequency refrigerator. The method for determining the defrosting cycle of a variable frequency refrigerator is described below:

[0059] For example, after the refrigerator has been running for a period of time, the thickness of the frost layer on the evaporator becomes larger, which will affect the refrigeration effect. Therefore, refrigerators usually need to be designed with an automatic defrosting function. How to accurately determine when to start defrosting is one of the key technologies for air-cooled frequency conversion to achieve energy saving and refrigeration reliability. At present, whether a defrosting operation is required is determined by presetting a fixed time. When the refrigerator is working, the cumulative running time of the refrigerator compressor is recorded by a timer. When the cumulative running time of the refrigerator compressor is greater than or equal to the preset fixed time, the refrigerator performs a defrosting operation, then resets the timer, and restarts recording the cumulative running time of the refrigerator compressor. The refrigerator is defrosted in a timed manner.

[0060] However, the growth rate of the frost layer on the refrigerator evaporator is not only related to the cumulative running time of the compressor, the number of door openings and closings, and the door opening time, but also affected by many factors such as user habits, ambient temperature and humidity, and the sealing condition of the refrigerator door. Frequent door opening will cause hot and humid air to enter the refrigerator, increasing the thickness of the frost layer on the evaporator surface. Defrosting the refrigerator only by timing cannot be flexibly performed according to the operating conditions of the compressor, resulting in reduced refrigerator refrigeration efficiency and increased refrigerator energy consumption.

[0061] like Figure 1 As shown, it is a flow chart of the method for determining the defrost cycle of a variable frequency refrigerator in this application.

[0062] The present application provides a method for determining a defrost cycle of a variable frequency refrigerator, comprising the following steps:

[0063] Before the step of obtaining the refrigerator operating parameters, the following steps are included:

[0064] S90: If the refrigerator is powered on for the first time, after the refrigerator is powered on for a sixth preset time, the step of obtaining refrigerator operating parameters is executed.

[0065] It is understandable that after the refrigerator is powered on for the first time, the refrigeration system (including components such as the compressor, condenser, and evaporator) needs a certain amount of time to operate and coordinate in order to achieve the best refrigeration effect. During this period of time, the various components of the refrigeration system will gradually enter the working state and prepare for the subsequent refrigeration process. During the operation of the refrigeration system, the temperature inside the refrigerator can gradually decrease. In order to ensure the stability and uniformity of the temperature inside the refrigerator, it is necessary to wait for a period of time before turning on the refrigeration function. For refrigerators with defrost functions, the defrost process is usually carried out automatically after the refrigeration system has been running for a period of time. Therefore, waiting for a period of time after the refrigerator is powered on for the first time can also ensure that the defrost system has enough time to prepare and start. In summary, in order to ensure the normal operation of the refrigeration system, it is necessary to wait for a period of time after the refrigerator is powered on for the first time before turning on the refrigeration function and the defrost function.

[0066] In this embodiment, after the refrigerator is powered on for the first time, the defrost function is not in a normal operating state, so it is impossible to judge whether to turn on or off the defrost function of the refrigerator according to the operating parameters of the refrigerator in the power-on state. Therefore, in this application, when the refrigerator is powered on for the first time, after the refrigerator is powered on for the sixth preset time, the step of obtaining the refrigerator operating parameters is performed to prepare for the subsequent judgment of whether to turn on the defrost function of the refrigerator. The sixth preset time can be selected as 12 hours.

[0067] S100: Obtain refrigerator operating parameters; the refrigerator operating parameters include: compressor operating time at different frequencies, compressor speed, refrigerator door opening time; different compressor speeds correspond to compressor operating time at different frequencies, and refrigerators are generally provided with fixed compressor speed gears. In this application, the compressor speeds at different gears and the corresponding compressor operating time at different compressor speeds are obtained. The refrigerator door opening time includes the opening time of all doors. For example, when the refrigerator door and the freezer door are opened at the same time, the opening time of the two doors is recorded at the same time, wherein the door opening time is obtained through the door switch.

[0068] Among them, there is a certain correlation between the cumulative working time of the compressor and the frosting time of the evaporator. The frosting of the evaporator is the result of the combined effect of multiple factors, including but not limited to the working time of the compressor, the circulation volume of the refrigerant, the design of the evaporator, and environmental conditions (such as temperature and humidity). When the compressor works for a long time, the circulation volume of the refrigerant in the system increases, which may cause the temperature of the evaporator surface to decrease, thereby increasing the risk of frosting.

[0069] The speed of the compressor directly affects the compression efficiency of the refrigerant and the pressure change in the system. When the compressor speed increases, its ability to compress the refrigerant increases, which reduces the pressure of the refrigerant in the evaporator, thereby causing the evaporation temperature to drop. The temperature of the evaporator surface is a key factor affecting the frosting speed. When the evaporator surface temperature drops below the freezing point, the water vapor in the air will condense and freeze on the evaporator surface to form a frost layer. Therefore, the lower the temperature of the evaporator surface, the faster the frosting speed. Since the compressor speed directly affects the temperature of the evaporator, it also has an important impact on the frosting speed of the evaporator. When the compressor speed increases, the evaporation temperature decreases, resulting in an accelerated frosting speed on the evaporator surface. Conversely, when the compressor speed decreases, the evaporation temperature increases, and the frosting speed on the evaporator surface slows down. In summary, the cumulative working time of the compressor is similar to the frosting time of the evaporator. The higher the speed, the lower the evaporator temperature, and the faster the evaporator surface frost speed. Therefore, the present application uses the compressor speed to judge the degree of frosting of the refrigerator.

[0070] S200: Based on the compressor speed, the operating time of the compressor at different frequencies is corrected to obtain a compressor operating time correction value; the correction calculation of the compressor cumulative working time, in this embodiment, is based on the compressor speed of 3000rpm. When the speed exceeds this, the cumulative working time increases; when the speed is lower than this, the cumulative working time decreases.

[0071] The step of correcting the running time of the compressor at different frequencies based on the compressor speed to obtain a correction value of the compressor running time includes the following sub-steps:

[0072] S210: Based on the compressor speed, a speed correction coefficient is obtained; the speed correction coefficient is determined by the following formula:

[0073] k = P ÷ n;

[0074] In the formula, k is the speed correction coefficient; P is the compressor speed; n is the compressor speed setting reference value; wherein the compressor speed setting reference value can be selected as 3000rpm.

[0075] S220: Obtaining a compressor operation time correction value based on the correction coefficient and the operation time of the compressor at different frequencies; the compressor operation time correction value is determined by the following formula:

[0076] t y =P×t n ;

[0077] Where, t y is the compressor running time correction value, in min; t n is the running time of the compressor at different frequencies.

[0078] Specifically, the compressor runs for a time t1 at a speed of P1, a time t2 at a speed of P2, a time t3 at a speed of P3, and a time t4 at a speed of P5. n The running time at the speed is t n ; Then the compressor running time correction value is:

[0079] t y =(P1÷3000)×t1+(P2÷3000)×t2+(P3÷3000)×t3+...+(P n ÷3000)×t n .

[0080] S300: Correct the refrigerator door opening time to obtain a refrigerator door opening time correction value; it is worth noting that when the user frequently opens the refrigerator door, warm and humid air from the outside will enter the refrigerator. After these warm and humid air encounters cold inside the refrigerator, it is easy to condense into water droplets, and then frost forms inside the refrigerator. Among them, the length of time the door is opened will also affect the amount of frost; opening the door for a long time will allow more outside air to enter the refrigerator, increasing the possibility of frost. In summary, the refrigerator door opening time has a certain influence on refrigerator frost. Among them, the refrigerator refrigeration order is usually to refrigerate the refrigerator compartment and the freezer compartment in turn.

[0081] The step of correcting the refrigerator door opening time to obtain a refrigerator door opening time correction value comprises the following sub-steps:

[0082] S310: Determine a door opening time correction coefficient; the door opening time correction coefficient has a value range of 30 to 100 and is used to convert the refrigerator door opening time into an evaporator frosting time.

[0083] S320: Based on the refrigerator door opening time and the door opening time correction coefficient, a refrigerator door opening time correction value is obtained; the refrigerator door opening time correction value is determined by the following formula:

[0084] t m =a×t1÷60;

[0085] Where, t m is the refrigerator door opening time correction value, in min; a is the door opening time correction coefficient; t1 is the refrigerator door opening time.

[0086] Specifically, m =a×(accumulated door opening time for refrigeration + accumulated door opening time for variable temperature + accumulated door opening time for freezing)÷60; the door opening time is obtained in seconds. (If the refrigerator has multiple doors, the door opening time of each door is included in the calculation value of the refrigerator door opening time)

[0087] S400: Based on the compressor operation time correction value and the refrigerator door opening time correction value, the evaporator frosting time is obtained; the evaporator frosting time is determined by the following formula:

[0088] t e =t y +t m ;

[0089] Where, t e is the duration of evaporator frosting, which is equal to the sum of the refrigerator door opening time correction value and the compressor running time correction value.

[0090] S500: When the frosting time of the evaporator is greater than or equal to the first preset time, the defrosting operation is performed after the compressor stops running.

[0091] The step of performing a defrosting operation when the evaporator is frosted for a period of time greater than or equal to a first preset time and after the compressor stops running comprises the following sub-steps:

[0092] S510: When the evaporator frosting time is greater than or equal to the first preset time, determine whether the compressor operation time is greater than the second preset time; the second preset time is greater than the first preset time; the first preset time can be selected as 48h, and the second preset time can be selected as 49h.

[0093] S520: If yes, the compressor is controlled to stop running and the defrosting operation is performed.

[0094] Specifically, when the frost time of the evaporator te≥48h, the defrost operation of the refrigerator is started after the compressor stops running. If the frost time of the evaporator has reached 48h, and the waiting time is greater than 1h (that is, the cumulative frosting time has met the requirement of 48h, but the compressor is still running at this time and has not stopped running after 1h), the compressor is forced to stop running and directly enter the defrost process.

[0095] The refrigerator operation parameters also include: a first temperature value and a second temperature value of the evaporator when the refrigerating chamber and the freezing chamber stop refrigerating.

[0096] The method further comprises the following steps:

[0097] S600: Obtaining a real-time temperature value of the evaporator after a third preset time after a defrost operation; the third preset time may be 12 hours.

[0098] S700: Obtaining a first temperature reference value and a second temperature reference value based on the first temperature value and the second temperature value; the step of obtaining the first temperature reference value and the second temperature reference value based on the first temperature value and the second temperature value comprises the following sub-steps:

[0099] S710: Determine a temperature correction coefficient ΔT; the optimal value range of the temperature correction coefficient is 1°C to 4°C.

[0100] S720: Obtain a first temperature reference value and a second temperature reference value according to the temperature correction coefficient and based on the first temperature value and the second temperature value.

[0101] The first temperature reference value is determined by the following formula:

[0102] T1=T ce -ΔT;

[0103] Where, T1 is the first temperature reference value; T ce is the first temperature value; ΔT is the temperature correction coefficient;

[0104] The second temperature reference value is determined by the following formula:

[0105] T2=T de -ΔT;

[0106] Where, T2 is the second temperature reference value; T de is the second temperature value.

[0107] S800: When the refrigerator compartment is in the refrigeration state, if the temperature real-time value is less than or equal to the first temperature reference value, the compressor is controlled to stop running and the defrosting operation is performed; specifically, when the evaporator temperature real-time value T is less than or equal to the first temperature reference value, the evaporator temperature real-time value T is less than or equal to the first temperature reference value. e ≤T ce When -ΔT, the compressor stops running immediately and the defrost operation is performed.

[0108] S900: When the freezer compartment is in the refrigeration state, if the temperature real-time value is less than or equal to the second temperature reference value, the compressor is controlled to stop running and the defrosting operation is performed. Specifically, when the evaporator temperature real-time value T e ≤T de When -ΔT, the compressor stops running immediately and the defrost operation is performed.

[0109] After the step of obtaining the real-time value of the temperature of the evaporator after the third preset time after the defrosting operation, the following steps are also included:

[0110] S610: If the refrigerator is in the refrigeration state after the first defrosting operation, and the refrigerating chamber and the freezing chamber are in the refrigeration state after the third preset time, the first temperature value and the second temperature value are determined as the first preset value and the second preset value; specifically, if the valid values ​​of the first temperature value and the second temperature value are not obtained within 12 hours (that is, the first refrigeration cycle after the refrigerator defrosts has not met the refrigeration stop refrigeration condition or the freezing stop refrigeration condition), the first temperature value and the second temperature value are used for subsequent defrosting judgment conditions according to the first preset value and the second preset value. Among them, the first preset value can be -28°C, and the second preset value can be -34°C.

[0111] S620: Based on the first preset value and the second preset value, obtain a first temperature reference value and a second temperature reference value; specifically, the first temperature reference value T1 = -28 - ΔT; the second temperature reference value T2 = -34 - ΔT.

[0112] S630: If the real-time temperature value is less than or equal to the first temperature reference value, and the duration is greater than or equal to a fourth preset time, the compressor is controlled to stop running and a defrosting operation is performed; the fourth preset time can be selected as 10 minutes.

[0113] S640: If the real-time temperature value is less than or equal to the second temperature reference value, and the duration is greater than or equal to the fourth preset time, the compressor is controlled to stop running and the defrosting operation is performed. The principle of judging whether to perform the defrosting operation by the evaporator temperature is as follows: when the frost layer of the evaporator is thick, the fan cannot bring the evaporator cold energy into each compartment of the refrigerator. At this time, the evaporator temperature will be significantly lower than the temperature during normal refrigeration. Therefore, when the evaporator temperature is low, it means that the frost layer on the surface of the evaporator is thick, and the defrosting operation needs to be performed to remove the frost layer on the surface.

[0114] The method further comprises the following steps:

[0115] S1000: If the refrigerator is in the refrigeration state for a time greater than the fifth preset time, the compressor is controlled to stop running and the defrosting operation is performed; the fifth preset time is greater than the first preset time, the second preset time, the third preset time, and the fourth preset time. Among them, when the above conditions are continuously not triggered, the present application sets the longest defrosting cycle protection time, i.e., the fifth preset time, which can be selected within the range of 72h to 96h. If the refrigerator's refrigeration time reaches the fifth preset time, the compressor is controlled to stop running and the defrosting operation is performed.

[0116] It is worth noting that after the refrigerator enters the defrost process again, the accumulated working time of the compressor is reset to zero, and the door opening time during the defrost period is not included in the total time. After the refrigerator compressor starts working again, the timing of the accumulated working time of the compressor, the door opening time, and the natural time will start again.

[0117] This application uses the original refrigeration and control system of the refrigerator, without adding other additional parts, to provide a method for determining the defrosting cycle of a variable frequency refrigerator. The control method is simple, the control rules are highly applicable, and the product design and development cycle is short. The frost layer thickness of the evaporator can be accurately determined, and defrosting can be started when necessary, which can ensure the reliability of defrosting of the refrigerator and reduce the operating energy consumption of the refrigerator.

[0118] The present application provides a method for determining the defrost cycle of a variable frequency refrigerator, which is provided with three defrost operation determination conditions:

[0119] 1. By collecting the actual working time of the variable frequency refrigerator compressor at different frequencies, the corrected cumulative working time of the compressor is calculated; the refrigerator door opening time is collected, and the cumulative frosting time of the evaporator is obtained through the corrected cumulative working time of the compressor and the refrigerator door opening time, and the cumulative frosting time of the evaporator is used to determine whether the refrigerator performs the defrosting operation.

[0120] 2. By collecting the evaporator temperature when the refrigerator stops refrigerating and the freezer stops refrigerating, the refrigerator temperature reference value and the freezer temperature reference value are obtained through the evaporator temperature, and finally the evaporator temperature real-time value and the refrigerator temperature reference value and the freezer temperature reference value are used to determine whether the refrigerator performs the defrost operation.

[0121] 3. Set the longest defrost cycle protection time to ensure that the refrigerator can perform defrost operation normally when judgment condition 1 and judgment condition 2 are not met.

[0122] The present application provides a variable frequency refrigerator defrosting cycle determination method, which can indirectly obtain the evaporator frost layer thickness through the compressor speed and the evaporator temperature, so as to start defrosting when necessary, which can not only ensure the reliability of refrigerator defrosting, but also reduce the operating energy consumption of the refrigerator to avoid the thick frost layer affecting the refrigerator's refrigeration effect; the thick frost layer will significantly reduce the refrigerator's refrigeration efficiency, making it difficult for the temperature inside the refrigerator to reach an ideal state. This will not only damage the freshness and taste of the food, but also may cause the food to spoil. Since the frost layer occupies a part of the space inside the refrigerator, the effective volume of the refrigerator is reduced, further affecting the refrigeration effect. It can also avoid the increase in refrigerator power consumption caused by the thick frost layer.

[0123] Among them, a thick frost layer not only increases the burden on the compressor, but may also cause the circuits and components inside the refrigerator to get damp, causing circuit failures. In the long run, this may shorten the service life of the refrigerator. In addition, a compressor that is frequently started and stopped may also be scrapped prematurely due to excessive wear. The surface of the frost layer is moist, which can easily become a breeding ground for bacteria. Once the frost layer thaws, bacteria may flow into the food with the melt water, causing cross contamination and posing a threat to food safety. Timely cleaning of the frost layer can avoid the above phenomenon and increase the service life of the refrigerator.

[0124] The above specific implementation methods further explain in detail the purpose, technical solutions and beneficial effects of the embodiments of the present application. It should be understood that the above are only specific implementation methods of the embodiments of the present application and are not used to limit the protection scope of the embodiments of the present application. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the embodiments of the present application should be included in the protection scope of the embodiments of the present application.

Claims

1. A method for determining the defrosting cycle of a variable frequency refrigerator, characterized in that: include: Get refrigerator operating parameters; The refrigerator operation parameters include: the operation time of the compressor at different frequencies, the compressor speed, and the refrigerator door opening time; Based on the compressor speed, correcting the running time of the compressor at different frequencies to obtain a compressor running time correction value; Correcting the refrigerator door opening time to obtain a refrigerator door opening time correction value; Based on the compressor running time correction value and the refrigerator door opening time correction value, obtaining the evaporator frosting time; When the frosting time of the evaporator is greater than or equal to the first preset time, the defrosting operation is performed after the compressor stops running.

2. A method for determining defrosting cycle of a variable frequency refrigerator according to claim 1, characterized in that: The step of correcting the running time of the compressor at different frequencies based on the compressor speed to obtain a corrected value of the compressor running time includes: Based on the compressor speed, a speed correction coefficient is obtained; the speed correction coefficient is determined by the following formula: k = P ÷ n; Where, k is the speed correction coefficient; P is the compressor speed; n is the compressor speed setting reference value; Based on the correction coefficient and the running time of the compressor at different frequencies, a compressor running time correction value is obtained; the compressor running time correction value is determined by the following formula: t y =P×t n ; In the formula, t y is the compressor running time correction value; t n is the running time of the compressor at different frequencies.

3. A method for determining defrosting cycle of a variable frequency refrigerator according to claim 1, characterized in that: The step of correcting the refrigerator door opening time to obtain a refrigerator door opening time correction value comprises: Determine the door opening time correction factor; Based on the refrigerator door opening time and the door opening time correction coefficient, a refrigerator door opening time correction value is obtained; the refrigerator door opening time correction value is determined by the following formula: t m =a×t1÷60; Where, t m is the refrigerator door opening time correction value; a is the door opening time correction coefficient; t1 is the refrigerator door opening time.

4. A method for determining defrosting cycle of a variable frequency refrigerator according to claim 1, characterized in that: The evaporator frosting time is determined by the following formula: t e =t y +t m ; In the formula, t e It is the duration of evaporator frosting.

5. A method for determining defrosting cycle of a variable frequency refrigerator according to claim 1, characterized in that: When the evaporator is frosted for a period of time greater than or equal to a first preset time, after the compressor stops running, the step of performing a defrosting operation comprises: When the evaporator is frosted for a period of time greater than or equal to a first preset time, determining whether the compressor operation time is greater than a second preset time; the second preset time is greater than the first preset time; If yes, the compressor is controlled to stop running and the defrost operation is performed.

6. A method for determining defrosting cycle of a variable frequency refrigerator according to claim 1, characterized in that: The refrigerator operation parameters also include: a first temperature value and a second temperature value of the evaporator when the refrigerator compartment and the freezer compartment stop refrigerating; The method further comprises: Obtaining the real-time temperature value of the evaporator after the third preset time after the defrost operation; Based on the first temperature value and the second temperature value, obtaining a first temperature reference value and a second temperature reference value; When the refrigerating chamber is in a refrigerating state, if the real-time temperature value is less than or equal to the first temperature reference value, the compressor is controlled to stop running and a defrosting operation is performed; When the freezing chamber is in a refrigeration state, if the real-time temperature value is less than or equal to the second temperature reference value, the compressor is controlled to stop running and a defrosting operation is performed.

7. A method for determining defrosting cycle of a variable frequency refrigerator according to claim 6, characterized in that: The step of obtaining a first temperature reference value and a second temperature reference value based on the first temperature value and the second temperature value comprises: Determine the temperature correction factor; Obtaining a first temperature reference value and a second temperature reference value based on the first temperature value and the second temperature value according to the temperature correction coefficient; The first temperature reference value is determined by the following formula: T1=T ce -ΔT; Where, T1 is the first temperature reference value; T ce is the first temperature value; ΔT is the temperature correction coefficient; The second temperature reference value is determined by the following formula: T2=T de -ΔT; Where, T2 is the second temperature reference value; T de is the second temperature value.

8. A method for determining defrosting cycle of a variable frequency refrigerator according to claim 6, characterized in that: After the step of obtaining the real-time value of the temperature of the evaporator after the third preset time after the defrosting operation, the method further includes: If the refrigerator is in a refrigeration state after the first defrosting operation, and the refrigerating chamber and the freezing chamber are in a refrigeration state after the third preset time, the first temperature value and the second temperature value are determined as the first preset value and the second preset value; Based on the first preset value and the second preset value, obtaining a first temperature reference value and a second temperature reference value; If the real-time temperature value is less than or equal to the first temperature reference value, and the duration is greater than or equal to a fourth preset time, the compressor is controlled to stop running and a defrosting operation is performed; If the real-time temperature value is less than or equal to the second temperature reference value, and the duration is greater than or equal to a fourth preset time, the compressor is controlled to stop running and a defrosting operation is performed.

9. A method for determining defrosting cycle of a variable frequency refrigerator according to claim 1, characterized in that: The method further comprises: If the refrigerator is in the refrigeration state for a time greater than a fifth preset time, the compressor is controlled to stop running and a defrost operation is performed; the fifth preset time is greater than the first preset time, the second preset time, the third preset time, and the fourth preset time.

10. A method for determining defrosting cycle of a variable frequency refrigerator according to claim 1, characterized in that: Before the step of obtaining the refrigerator operation parameters, the method includes: If the refrigerator is powered on for the first time, the step of obtaining refrigerator operating parameters is performed after the refrigerator is powered on for a sixth preset time.

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