A defrosting control method and air conditioner

Abstract

The application provides a defrosting control method and an air conditioner, and relates to the technical field of air conditioners. The technical problem that no defrosting, no defrosting of frost or no defrosting due to weather influence easily occurs during the timed defrosting is solved. The method is a defrosting method for the air conditioner without an outer ring temperature sensor, comprising the following steps: collecting operation parameters; obtaining a temperature difference value AT based on the collected operation parameters; obtaining air conditioner system operation instantaneous capacity Q based on the collected operation parameters and / or the temperature difference value AT; judging whether to enter defrosting based on the obtained air conditioner system operation instantaneous capacity Q and the collected operation parameters; and performing defrosting treatment when the judgment result is to enter defrosting. The defrosting judgment is performed by calculating the instantaneous capacity based on the inner ring temperature, the inner coil temperature and the actual operation condition of the air conditioner. The best timing of entering defrosting can be flexibly controlled according to the actual condition, the operation comfort of the air conditioner is ensured, and the influence on the next cycle heating capacity is reduced.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and in particular to a defrosting control method and an air conditioner. Background Technology

[0002] With rapid social development and the continuous improvement of people's living standards, people's requirements for quality of life are also increasing. Air conditioners, as important electrical appliances, have gradually entered thousands of households and are used by everyone. The functions of air conditioners that everyone is familiar with are cooling and heating. However, when using air conditioners in winter, the outdoor unit will frost up as the air conditioner runs for a long time in heating mode. The longer the running time, the more frost will form, which will seriously affect the heating effect of the air conditioner and even damage the air conditioner compressor, reducing the performance of the air conditioner.

[0003] In existing technologies, air conditioner defrosting is mostly controlled by outdoor unit parameters and outdoor temperature. When the outdoor unit of the air conditioner is not equipped with parameters such as ambient temperature and humidity sensors, the defrosting process is mainly controlled by the temperature of the heat exchanger tubes in the indoor unit and the temperature of the inner environment. Defrosting is carried out using a timed defrosting method. In special weather conditions, this defrosting method is prone to problems such as failure to defrost, incomplete defrosting, and untimely defrosting, resulting in poor frost formation and affecting the heating capacity of the next cycle. This invention provides a new defrosting control method that is more flexible than timed defrosting and is not affected by weather changes. Summary of the Invention

[0004] The purpose of this invention is to provide a defrosting control method and an air conditioner to solve the technical problem in the prior art where, when there is no outdoor ambient temperature sensor, timed defrosting is easily affected by weather and may fail to defrost or may not defrost completely.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a first aspect, the present invention provides a defrosting control method for an air conditioner without an external loop temperature sensor, the method comprising:

[0007] Collect operating parameters;

[0008] Based on the collected operating parameters, the temperature difference value ΔT is obtained;

[0009] Based on the collected operating parameters and / or temperature difference value △T, the instantaneous operating capacity Q of the air conditioning system is obtained;

[0010] Based on the obtained instantaneous operating capacity Q of the air conditioning system and the collected operating parameters, it is determined whether to enter the defrosting phase;

[0011] When the judgment result indicates that defrosting is required, the defrosting process is executed.

[0012] Furthermore, the collected operating parameters include: compressor running time, compressor operating frequency F, indoor fan speed R, indoor unit air volume q_m, indoor ambient temperature Tc, and indoor unit coil temperature Ta.

[0013] Furthermore, before collecting operational parameters, the following steps are also included:

[0014] Determine if the air conditioning system is in heating mode;

[0015] When the judgment result indicates that the heating mode is in operation, the timer starts timing the running time TD1.

[0016] When the running time TD1 is greater than or equal to the set period time △t1, the running parameters are collected.

[0017] Furthermore, the instantaneous operating capacity Q of the air conditioning system is calculated using the following formula:

[0018] Q = A * △T + B * F + C; or,

[0019] Q = b * R * △T + c, or,

[0020] Q = q_m * △T + d;

[0021] △T = Ta - Tc;

[0022] Where A, B, and b are correction coefficients for each operating parameter; C, c, and d are adjustment coefficients, all of which are dimensionless parameters; Ta is the indoor unit coil temperature; Tc is the indoor ambient temperature; F is the compressor operating frequency; R is the indoor fan speed; q_m is the indoor fan air volume and the external pipe temperature Tw.

[0023] Furthermore, the correction coefficient A ranges from 10 to 100; B ranges from 5 to 10; b ranges from 0 to 10; the adjustment coefficient C ranges from 100 to 1200; c ranges from 0 to 100; and d ranges from 5 to 20.

[0024] Furthermore, as an optional embodiment of the present invention, determining whether to enter defrosting mode based on the obtained instantaneous operating capacity Q of the air conditioning system and the collected operating parameters includes:

[0025] By collecting multiple sets of operating parameters at different time periods, the instantaneous operating capacity Q of multiple air conditioning coefficients within different time periods can be obtained;

[0026] Among the multiple instantaneous air conditioning coefficients Q obtained at different time periods, the maximum value is found as the capacity attenuation comparison base Q_MAX;

[0027] When the latest obtained instantaneous operating capacity of the air conditioning coefficient Q is less than x times the capacity attenuation comparison base Q_MAX, it is determined whether the defrosting condition has been met.

[0028] When the temperature difference ΔT < the first preset temperature T1, or when the outer tube temperature Tw = the second preset temperature T2, it is determined that the defrosting conditions have been met, and defrosting begins.

[0029] Furthermore, x takes values ​​from 0.1 to 1.

[0030] Furthermore, the first preset temperature T1 is in the range of 10-20℃.

[0031] Furthermore, the second preset temperature T2 has a range of -16℃ to 0℃.

[0032] Furthermore, as another optional embodiment of the present invention, the step of determining whether to enter defrost mode based on the obtained instantaneous operating capacity Q of the air conditioning system and the collected operating parameters includes:

[0033] By collecting n sets of operating parameters at different time periods, the instantaneous operating capacity Q of n air conditioning coefficients within different time periods can be obtained;

[0034] The average capacity value is calculated by using the instantaneous capacity Q of the n air conditioning coefficients obtained at different time periods, and is used as the comparison base Q_AV for capacity attenuation.

[0035] When the latest obtained instantaneous operating capacity Q of the air conditioning system is less than y times the capacity attenuation comparison base Q_AV, it is determined whether the defrosting condition has been met.

[0036] When the temperature difference ΔT < the first preset temperature T1, or when the outer tube temperature Tw = the second preset temperature T2, it is determined that the defrosting conditions have been met, and defrosting begins.

[0037] Furthermore, the value of y ranges from 0.2 to 5.

[0038] Furthermore, when the determination result indicates that defrosting has begun, the defrosting process is executed, including:

[0039] Start defrosting;

[0040] Start the timer to count down the defrosting time TD2;

[0041] When the defrosting time TD2 reaches the set defrosting time △t2, determine whether the defrosting exit condition has been met.

[0042] When the absolute temperature difference between the inner tube and the outer tube is greater than or equal to the third preset temperature T3, or when the temperature of the outer tube Tw reaches the fourth preset temperature T4, it is determined that the defrosting exit condition has been met.

[0043] Furthermore, when the judgment result indicates that the conditions for exiting defrosting have not been met:

[0044] Increase defrosting ability and continue defrosting;

[0045] After running for a set duration △t3, defrosting ends and the system switches to normal heating operation.

[0046] The defrosting control method provided by this invention calculates the instantaneous capacity based on the internal ambient temperature, internal coil temperature, and actual air conditioner operation to determine defrosting. It can flexibly control the optimal time for defrosting according to the actual situation, ensuring the comfort of air conditioner operation and reducing the impact on the heating capacity of the next cycle. Compared with existing methods, this method is more flexible and can more accurately reflect the system operation by judging capacity changes, thus enabling timely defrosting.

[0047] Secondly, the present invention provides an air conditioner for performing the method. Attached Figure Description

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

[0049] Figure 1 This is the control logic diagram of the defrosting control method of the present invention. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0051] like Figure 1As shown, this invention provides a defrosting control method for air conditioners without an external ambient temperature sensor. When the air conditioner is running in heating mode, operating information is collected, including compressor running time, compressor frequency, inner ambient temperature, and indoor unit coil temperature. The instantaneous operating capacity of the air conditioning system is calculated, and the timing of defrosting is determined by the attenuation of this instantaneous capacity and the difference between the inner ambient temperature and the indoor coil temperature. This invention uses capacity changes (primarily represented by capacity attenuation, but the difference between the inner ambient temperature and the indoor coil temperature is used in the instantaneous capacity calculation) to reflect the frost situation. Compared to timed defrosting, this method is more flexible and reduces the impact of weather changes on system performance. Determining the optimal time for defrosting based on capacity attenuation avoids problems such as defrosting without frost or delayed defrosting, shortens defrosting time, and reduces the impact of defrosting on indoor temperature drop, thereby improving heating comfort.

[0052] Defrosting control methods include:

[0053] Determine if the air conditioning system is in heating mode;

[0054] When the judgment result indicates that the heating mode is in operation, the timer starts timing the running time TD1.

[0055] When the running time TD1 is greater than or equal to the set period time △t1, the running parameters are collected.

[0056] In other words, after receiving the start command, the air conditioner first determines whether the current operating mode is heating mode. If it is heating mode, the timing module is activated to record the compressor start-up time. After the compressor runs for a certain period of time, it is determined whether the running time TD1 meets the set cycle time △t1. If the condition is not met, the timing continues. When the running time meets the preset value, the operating parameters are collected. The operating parameters include compressor running time, compressor running frequency F, indoor fan speed R, indoor unit air volume q_m, indoor ambient temperature Tc, and indoor unit coil temperature Ta.

[0057] Furthermore, in this invention, the range of the set period time Δt1 is 10-40 minutes.

[0058] Based on the collected operating parameters, the temperature difference value ΔT is obtained; where ΔT = indoor unit coil temperature Ta - indoor ambient temperature Tc, which is the temperature difference between the inner coil and the inner ring; this temperature difference value can be positive or negative. If the temperature difference value is negative, its absolute value is used for judgment. After calculating the temperature difference between the inner ring and the inner coil, the instantaneous capacity is calculated, that is:

[0059] Based on the collected operating parameters and / or temperature difference ΔT, the instantaneous operating capacity Q of the air conditioning system is obtained, and the instantaneous capacity is calculated by fitting the inner pipe, inner loop, and operating parameters.

[0060] In this invention, there are three methods for calculating the instantaneous operating capacity Q of the air conditioning system:

[0061] The instantaneous operating capacity Q of the air conditioning system is calculated using the following formula:

[0062] (1) Q = A*△T + B*F + C; or,

[0063] (2) Q = b * R * △T + c, or,

[0064] (3) Q = q_m*△T + d;

[0065] △T = Ta - Tc;

[0066] Where A, B, and b are correction coefficients for each operating parameter; C, c, and d are adjustment coefficients, all of which are dimensionless parameters with no specific meaning; Ta is the indoor unit coil temperature; Tc is the indoor ambient temperature; F is the compressor operating frequency; R is the indoor fan speed; q_m is the indoor fan air volume and the external pipe temperature Tw.

[0067] Furthermore, the correction coefficient A ranges from 10 to 100; B ranges from 5 to 10; b ranges from 0 to 10; the adjustment coefficient C ranges from 100 to 1200; c ranges from 0 to 100; and d ranges from 5 to 20. It should be noted that the coefficients listed here are for illustrative purposes only and are not intended to limit their specific values; the actual values ​​of the correction coefficients can be adjusted.

[0068] Any of the three formulas above can be used to calculate the instantaneous operating capacity of an air conditioning system. In actual use, the appropriate formula can be selected based on the specific circumstances.

[0069] After calculating the instantaneous capacity based on the operating parameters, the calculated value is compared to determine the attenuation, and then it is determined whether to enter the defrosting stage. In other words, based on the obtained instantaneous operating capacity Q of the air conditioning system and the collected operating parameters, it is determined whether to enter the defrosting stage.

[0070] This invention provides two methods for determining capability attenuation:

[0071] The first method of judgment is: the maximum ability value judgment method; specifically:

[0072] By collecting multiple sets of operating parameters at different time periods, the instantaneous operating capacity Q of multiple air conditioning coefficients within different time periods can be obtained;

[0073] Among the multiple instantaneous air conditioning coefficients Q obtained at different time periods, the maximum value is found as the capacity attenuation comparison base Q_MAX;

[0074] When the latest obtained instantaneous operating capacity Q of the air conditioning coefficient is less than x times the capacity attenuation comparison base Q_MAX, it is determined whether the defrosting condition has been met; x takes the value of 0.1-1.

[0075] When the temperature difference ΔT < the first preset temperature T1, or when the outer tube temperature Tw = the second preset temperature T2, it is determined that the defrosting conditions have been met, and defrosting begins.

[0076] Furthermore, the first preset temperature T1 is in the range of 10-20℃.

[0077] Furthermore, the second preset temperature T2 has a range of -16℃ to 0℃.

[0078] During the heating process, the thickening of the frost layer will reduce the heating capacity of the system. The capacity has a maximum value. By comparing each calculated instantaneous capacity, the maximum capacity value is determined and recorded as the comparison base after the capacity decays. When the instantaneous capacity decay caused by frost is x times (range: 0.1 to 1) times the maximum capacity Q_MAX, and at the same time the temperature difference between the inner ring and the inner tube is less than T1 (range: 10 to 20℃) or the temperature of the outer tube reaches T2 (range: 0 to -16℃), it is determined that defrosting has begun.

[0079] The second method of judgment is the average value method, specifically:

[0080] By collecting n sets of operating parameters at different time periods, the instantaneous operating capacity Q of n air conditioning coefficients within different time periods can be obtained;

[0081] The average capacity value is calculated by using the instantaneous capacity Q of n air conditioning coefficients obtained at different time periods, and is used as the comparison base Q_AV for capacity attenuation.

[0082] When the latest obtained instantaneous operating capacity Q of the air conditioning system is less than y times the capacity attenuation comparison base Q_AV, it is determined whether the defrosting condition has been met.

[0083] When the temperature difference ΔT < the first preset temperature T1, or when the outer tube temperature Tw = the second preset temperature T2, it is determined that the defrosting conditions have been met, and defrosting begins.

[0084] Furthermore, the value of y ranges from 0.2 to 5.

[0085] When the instantaneous capacity is calculated, the counter is started synchronously, and the result is recorded once. When the count reaches n (range: 5 to 100 times), the average capacity is calculated. The counting restarts after each average capacity calculation. By comparing the average capacity with the instantaneous capacity, the capacity decay is judged, and the timing for defrosting is determined. Defrosting can begin when the preset capacity decay control range (Q < Q_AV*y (range: 0.2-5)) is met, and the temperature difference between the inner tube and the inner ring meets the preset value T1 or the outer tube temperature reaches T2.

[0086] When the determination result indicates that defrosting is required, the defrosting process is executed, including:

[0087] Start defrosting;

[0088] Start the timer to count down the defrosting time TD2;

[0089] When the defrosting time TD2 reaches the set defrosting time △t2, determine whether the defrosting exit condition has been met.

[0090] When the absolute temperature difference between the inner tube and the outer tube is greater than or equal to the third preset temperature T3, or when the temperature of the outer tube Tw reaches the fourth preset temperature T4, it is determined that the defrosting exit condition has been met.

[0091] Furthermore, the defrosting time Δt2 is set to a range of 0-20 minutes; the third preset temperature T3 is set to a range of 20℃-30℃±0.5℃; and the fourth preset temperature T4 is set to a range of 0-20℃.

[0092] When the judgment result indicates that the conditions for exiting defrosting have not been met:

[0093] Increase defrosting capacity, decrease the opening of the electronic expansion valve X, and continue defrosting;

[0094] After running for a set duration △t3, defrosting ends and the system switches to normal heating operation.

[0095] Specifically, after entering the defrosting phase, a timer is started, and the defrosting time is used as one of the conditions for exiting defrosting. When TD2 = Δt2 (range: 0-20 min) and the absolute temperature difference between the inner tube and the inner ring is greater than T3 (range: 20℃-30℃ ± 0.5), or when the temperature of the outer tube is obtained and it is greater than T4 (range: 0-20℃), defrosting is exited. If the above conditions are not met, the opening is reduced by X (range: 5-100 P), and defrosting continues for Δt3 (range: 3-10 min), then defrosting ends and normal heating operation resumes.

[0096] The defrosting control method provided by this invention calculates the instantaneous capacity based on the internal ambient temperature, internal coil temperature, and actual air conditioner operation to determine defrosting. It can flexibly control the optimal time for defrosting according to the actual situation, ensuring the comfort of air conditioner operation and reducing the impact on the heating capacity of the next cycle. Compared with existing methods, by judging the capacity change, it can more accurately reflect the system operation and defrost in a timely manner.

[0097] The present invention provides an air conditioner for performing the method.

[0098] The air conditioner provided by this invention solves the problems of defrosting without frost or failing to defrost when defrosting by timed defrosting in the absence of an outdoor ambient temperature sensor. It calculates the instantaneous capacity based on the indoor ambient temperature, the indoor coil temperature, and the actual operating conditions of the air conditioner to determine defrosting, thus improving the flexibility of defrosting control. Compared with timed defrosting, it is more flexible and unaffected by weather changes, solving the problems of inflexibility, incomplete defrosting, or excessively long defrosting time caused by using only the indoor ambient temperature and the indoor coil temperature to control defrosting. It determines the optimal time for defrosting by capacity decay, shortens the defrosting time, reduces the indoor temperature drop during the defrosting process, and thus improves heating comfort.

[0099] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A defrosting control method, characterized in that, A method for defrosting an air conditioner without an outer loop temperature sensor, the method comprising: When the air conditioning system is in heating mode, the timer starts and counts the running time TD1. When the running time TD1 is greater than or equal to the set cycle time △t1, the running parameters are collected. The running parameters include compressor running time, compressor running frequency F, indoor fan speed R, indoor fan air volume q_m, indoor ambient temperature Tc, indoor unit coil temperature Ta, and outdoor pipe temperature Tw. Based on the collected operating parameters, the temperature difference value ΔT is obtained, and then the instantaneous operating capacity Q of the air conditioning system is obtained, which is calculated by the following formula: Q = A * △T + B * F + C; or, Q = b * R * △T + c, or, Q = q_m * △T + d; △T = Ta - Tc; Where A, B, and b are correction coefficients for each operating parameter; C, c, and d are adjustment coefficients, all of which are dimensionless parameters; Ta is the indoor unit coil temperature; Tc is the indoor ambient temperature; F is the compressor operating frequency; R is the indoor fan speed; and q_m is the indoor fan air volume. Based on the obtained instantaneous operating capacity Q of the air conditioning system and the collected operating parameters, it is determined whether to enter the defrosting phase, including: By collecting multiple sets of operating parameters at different time periods, the instantaneous operating capacity Q of multiple air conditioning systems at different time periods is obtained; among the obtained instantaneous operating capacity Q of multiple air conditioning systems at different time periods, the maximum value is found as the capacity attenuation comparison base Q_MAX; when the latest obtained instantaneous operating capacity Q of the air conditioning system is less than 0.1-1 times the capacity attenuation comparison base Q_MAX, it is determined whether the defrosting condition has been met. Alternatively, by collecting n sets of operating parameters at different time periods, the instantaneous operating capacity Q of the air conditioning system at different time periods can be obtained; the average capacity value can be calculated using the instantaneous operating capacity Q of the air conditioning system at different time periods, which is used as the capacity attenuation comparison base Q_AV; when the latest obtained instantaneous operating capacity Q of the air conditioning system is less than 0.2-5 times the capacity attenuation comparison base Q_AV, it is determined whether the defrosting condition has been met. When the temperature difference ΔT < the first preset temperature T1, or when the outer tube temperature Tw = the second preset temperature T2, it is determined that the defrosting conditions have been met and defrosting begins; where the first preset temperature T1 ranges from 10 to 20℃, and the second preset temperature T2 ranges from -16℃ to 0℃. When the judgment result indicates that defrosting is required, the defrosting process is executed.

2. The method according to claim 1, characterized in that, When the determination result indicates that defrosting has begun, the defrosting process is executed, including: Start defrosting; Start the timer to count down the defrosting time TD2; When the defrosting time TD2 reaches the set defrosting time △t2, determine whether the defrosting exit condition has been met. When the absolute temperature difference between the indoor unit coil temperature Ta and the outdoor unit temperature Tw is greater than or equal to the third preset temperature T3, or when the outdoor unit temperature Tw reaches the fourth preset temperature T4, it is determined that the defrosting exit condition has been met.

3. The method according to claim 2, characterized in that, When the judgment result indicates that the conditions for exiting defrosting have not been met: Increase defrosting ability and continue defrosting; After running for a set duration △t3, defrosting ends and the system switches to normal heating operation.

4. An air conditioner, characterized in that, Used to perform the method as described in any one of claims 1-3.

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