Defrosting system and defrosting method of finned heat exchanger and air conditioner outdoor unit

Abstract

The invention relates to the technical field of air conditioners, in particular to a defrosting system and method of a finned heat exchanger and an air conditioner outdoor unit. The defrosting system of the finned heat exchanger comprises a fan parameter monitoring module, a defrosting module and a control module, wherein the fan parameter monitoring module is configured to monitor the power variation of a fan in real time; and the data processing module is configured to analyze the power variation of the fan so as to judge whether the finned heat exchanger is frosted or not and perform defrosting operation. According to the scheme, the defect that it is difficult to accurately predict and respond to the actual frosting condition when an air conditioning system judges the frosting opportunity in the related technology is overcome, the frosting condition is accurately judged, the mistaken defrosting operation process is reduced, and then defrosting is conducted in time.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioners, and particularly to a defrosting system and method for a finned heat exchanger and an outdoor unit of an air conditioner. Background Art

[0002] Currently, when air conditioning equipment operates in a low-temperature environment, it will face the problem of frosting on the outdoor unit, which will affect the heat exchange efficiency and damage the long-term performance of the equipment.

[0003] Most of the existing defrosting technologies adopt timed defrosting or methods based on refrigerant temperature monitoring. These methods have certain limitations. For example, they cannot accurately predict and respond to the actual frosting situation, resulting in impaired thermal comfort for users.

[0004] Timed defrosting does not consider the actual operating conditions and may start when defrosting is not required or be delayed when defrosting is needed. And the temperature-based system may misjudge due to environmental temperature fluctuations or changes in the refrigerant state. Summary of the Invention

[0005] The present invention provides a defrosting system and method for a finned heat exchanger and an outdoor unit of an air conditioner, which are used to solve the defect that it is difficult for the air conditioning system in the related art to accurately predict and respond to the actual frosting situation when determining the frosting time, and to achieve accurate judgment of the frosting condition, reduce the mis-defrosting operation process, and then perform defrosting in a timely manner.

[0006] The present invention provides a defrosting system for a finned heat exchanger, including: a fan parameter monitoring module configured to monitor the power change of the fan in real time; a data processing module configured to analyze the power change of the fan to determine whether the finned heat exchanger is frosted and perform a defrosting operation.

[0007] According to the defrosting system for a finned heat exchanger provided by the present invention, the data processing module includes a calculation unit configured to calculate the frosting degree according to the power change of the fan, and when the frosting degree reaches a preset condition, remind that defrosting is required.

[0008] According to the defrosting system for a finned heat exchanger provided by the present invention, the calculation unit further includes a normalization processing sub-unit configured to generate a characteristic curve of the fan, perform normalization processing on the characteristic curve to obtain the frosting degree; the characteristic curve includes: the fan curve of the total pressure of the fan varying with the air flow rate and the power curve of the fan varying with the air flow rate when the fan is at the rated speed, and the first resistance curve of the finned heat exchanger varying with the air flow rate in the normal state, and the second resistance curve of the finned heat exchanger varying with the air flow rate in the frosted state.

[0009] A defrosting system for a finned heat exchanger provided by the present invention, the data processing module further includes a defrosting operation unit configured to perform a defrosting operation when the frosting degree reaches a preset condition.

[0010] A defrosting system for a finned heat exchanger provided by the present invention includes: a temperature and humidity detection module configured to obtain temperature and humidity parameters of the current environment; a temperature sensor configured to detect the refrigerant outlet temperature parameter of the finned heat exchanger; the data processing module further includes: a comparison unit configured to compare the refrigerant outlet temperature parameter with the dew point temperature corresponding to the temperature and humidity parameters; a judgment unit configured to determine that the finned heat exchanger will frost when the refrigerant outlet temperature parameter is lower than the dew point temperature.

[0011] A defrosting system for a finned heat exchanger provided by the present invention includes a networked data acquisition module configured to obtain weather parameters of the current location; the comparison unit is configured to compare the temperature and humidity parameters with the weather parameters to determine the dew point temperature of the current environment.

[0012] The present invention also provides a defrosting method for a finned heat exchanger, which is used for the defrosting system of the finned heat exchanger in any of the above embodiments, and includes: obtaining the power change amount of the fan; determining the frosting degree of the finned heat exchanger based on the power change amount; and performing a defrosting operation when the frosting degree reaches a preset condition.

[0013] The step of obtaining the power change amount of the fan in the defrosting method for a finned heat exchanger provided by the present invention includes: obtaining the instant power characteristics and the instant operation mode of the fan, where the instant power characteristics are the change characteristics of the power of the fan within a collection time period; when the instant power characteristics conform to the instant operation mode, determining the power change trend of the fan based on N adjacent instant power characteristics, and determining the power change amount according to the power change trend.

[0014] The step of performing a defrosting operation when the frosting degree reaches a preset condition in the defrosting method for a finned heat exchanger provided by the present invention includes: calculating the real-time frosting degree and comparing it with a preset threshold; when the frosting degree exceeds the preset threshold, starting a defrosting program.

[0015] Before the step of obtaining the power change amount of the fan in the defrosting method for a finned heat exchanger provided by the present invention, it further includes: obtaining the refrigerant outlet temperature parameter of the finned heat exchanger; when the refrigerant outlet temperature parameter is lower than the dew point temperature of the current environment, determining that the finned heat exchanger has a possibility of frosting.

[0016] A defrosting method for a finned heat exchanger provided by the present invention further includes, before the step of obtaining the power change amount of the blower: receiving the temperature and humidity parameters from the temperature and humidity detection module; receiving the weather parameters from the networked data acquisition module; and determining the dew point temperature of the current environment based on the temperature and humidity parameters and the weather parameters.

[0017] The present invention also provides an outdoor unit of an air conditioner, which adopts the defrosting method for the finned heat exchanger according to any one of the above embodiments when performing defrosting.

[0018] The defrosting system for the finned heat exchanger provided by the present invention can help identify changes in the blower load by real-time monitoring of the power change amount of the blower. The data processing module analyzes the power change amount of the blower and can accurately determine whether frosting has occurred. The defrosting method for the finned heat exchanger is the specific application process of the above system. This method is based on the analysis of the blower power change to implement the defrosting decision. The outdoor unit of the air conditioner provided by the present invention constructs a comprehensive and efficient frosting monitoring and processing system for the finned heat exchanger based on the above defrosting system and defrosting method, effectively solving the problems of inaccurate judgment of the frosting time and untimely response in the traditional method, reducing unnecessary defrosting operations, and thus improving the energy efficiency ratio and reliability of the entire air conditioning system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0020] Figure 1 It is a schematic diagram of the modules of the defrosting system for the finned heat exchanger provided by the present invention.

[0021] Figure 2 It is a schematic diagram of the characteristic curve of the blower generated by the defrosting system for the finned heat exchanger provided by the present invention.

[0022] Figure 3 It is a schematic diagram of the flow of the defrosting method for the finned heat exchanger provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the present invention with reference to the drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments in the present invention belong to the scope of protection of the present invention.

[0024] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0025] The following combines Figure 1 、 Figure 2 and Figure 3 to describe the defrosting system and defrosting method of the finned heat exchanger of the present invention.

[0026] The present invention provides a defrosting system for a finned heat exchanger, including a fan parameter monitoring module configured to monitor the power change of the fan in real time; a data processing module configured to analyze the power change of the fan to determine whether the finned heat exchanger is frosted and perform a defrosting operation. Among them, the real-time monitoring of the fan power by the fan parameter monitoring module indirectly determines frosting from the perspective of system operation efficiency. Since the fan's working power will change abnormally in order to maintain the air volume when facing the increased air resistance caused by frosting, this index can effectively reflect the working state of the finned heat exchanger.

[0027] Preferably, as Figure 1 shown, the defrosting system may further include: a temperature and humidity detection module configured to obtain the temperature and humidity parameters of the current environment; a temperature sensor configured to detect the refrigerant outlet temperature parameter of the finned heat exchanger. The frosting situation is comprehensively judged by combining the temperature and humidity parameters and the refrigerant outlet temperature parameter with the power change of the fan.

[0028] At this time, the data processing module may further include: a comparison unit configured to compare the refrigerant outlet temperature parameter with the dew point temperature corresponding to the temperature and humidity parameter; a determination unit configured to determine that the finned heat exchanger will frost when the refrigerant outlet temperature parameter is lower than the dew point temperature. Among them, monitoring the refrigerant outlet temperature parameter of the finned heat exchanger through a temperature sensor can be used to evaluate whether the equipment has a tendency to frost, because when the outlet temperature parameter drops below the dew point, the frosting risk will increase significantly. At this time, based on the power change amount, determining the frosting degree of the finned heat exchanger can make a more accurate judgment on the frosting state, preventing misjudgment of the system caused by changes in the fan power due to other factors. Among them, the dew point temperature can be obtained from the temperature and humidity parameters detected by the temperature and humidity detection module or can be obtained by connecting to the network.

[0029] Preferably, the system may further include a networked data acquisition module configured to acquire the weather parameters of the current location. The comparison unit is further configured to determine a more accurate dew point temperature of the current environment by comparing the temperature and humidity parameter and the weather parameter. The combined use of the temperature and humidity detection module and the networked data acquisition module ensures that the system can acquire and compare the on-site actual temperature and humidity with the forecast temperature and humidity in real time. This multi-source data comparison enhances the accuracy of environmental condition judgment and helps to eliminate misjudgment caused by local microclimate differences. The temperature sensor directly monitors the refrigerant outlet temperature parameter and compares it with the dew point temperature of the environment, which is the direct basis for judging the occurrence of frosting. When the refrigerant outlet temperature parameter is lower than the dew point temperature, the moisture in the air is likely to condense into frost on the fins.

[0030] This embodiment forms an intelligent decision-making system by integrating multiple modules such as temperature and humidity detection, networked data acquisition, refrigerant temperature monitoring, and fan parameter monitoring, and combining advanced data analysis algorithms, significantly improving the accuracy of the defrosting process of the finned heat exchanger. By integrating intelligent monitoring and analysis technologies, the present invention realizes accurate judgment of the defrosting demand of the finned heat exchanger, reducing both the waste of resources caused by misoperation and improving the energy efficiency and stability of the overall system.

[0031] According to a defrosting system for a finned heat exchanger provided by the present invention, the data processing module preferably includes a calculation unit configured to calculate the frosting degree according to the power change amount of the fan, and when the frosting degree reaches a preset condition, remind that defrosting is required.

[0032] Further, the data processing module may further include: a comparison unit configured to compare the temperature and humidity parameters with the weather parameters, and to compare the refrigerant outlet temperature parameter with the dew point temperature corresponding to the temperature and humidity parameters; a determination unit configured to determine that the finned heat exchanger will frost when the comparison result of the temperature and humidity parameters and the weather parameters is consistent and the refrigerant outlet temperature parameter is lower than the dew point temperature; specifically, the comparison unit obtains two sets of temperature and humidity parameters provided by the temperature and humidity detection module and the network data acquisition module, which are the real-time temperature and humidity of the current environment and the temperature and humidity of the weather forecast at the current location. The comparison helps to verify the accuracy of the environmental temperature and humidity, eliminate local anomalies, and ensure the reliability of subsequent judgments. The refrigerant outlet temperature parameter (monitored by a temperature sensor) is compared with the dew point temperature calculated based on the current environmental temperature and humidity. If the refrigerant outlet temperature parameter is lower than the dew point temperature, it indicates that frosting is likely to have started or is about to start on the fins. Based on the results of the comparison unit, the determination unit makes a decision on whether frosting occurs.

[0033] Preferably, the defrosting system of the finned heat exchanger first starts an intelligent judgment process for the possibility of frosting: the system monitors the current environmental conditions through an integrated temperature and humidity detection device and compares them with the real-time temperature and humidity parameters of the local weather station obtained from the network to verify the consistency of internal and external information. On this basis, the refrigerant outlet temperature parameter of the finned heat exchanger is further checked. If this temperature is lower than the dew point temperature calculated based on the current environmental temperature and humidity, this is regarded as a warning signal for frosting of the finned heat exchanger, indicating that frost is very likely to start or has already formed on the fin surface in the current environment. The calculation unit first has the determination unit confirm the frosting trend of the finned heat exchanger and then performs a detailed calculation of the frosting degree, avoiding unnecessary calculations and resource consumption when there is no frosting risk. Calculating the frosting degree on the premise of knowing the frosting risk can more specifically analyze the change in fan power, reduce misjudgments caused by other factors (such as short-term air flow disturbances, external interferences, etc.), and improve the accuracy and reliability of the frosting degree calculation.

[0034] According to a defrosting system of a finned heat exchanger provided by the present invention, the calculation unit further includes a normalization processing subunit configured to generate a characteristic curve of the fan, perform normalization processing on the characteristic curve to obtain the frosting degree; the characteristic curve includes: the fan curve in which the total pressure of the fan changes with the air flow rate at the rated speed of the fan, the power curve in which the power of the fan changes with the air flow rate, the first resistance curve of the finned heat exchanger changing with the air flow rate under normal conditions, and the second resistance curve of the finned heat exchanger changing with the air flow rate in the frosting state. The normalization processing subunit unifies the above curves to a comparable standard scale, eliminates the influence caused by differences in equipment specifications, test conditions, etc., and enables the data obtained under different conditions to be directly compared. By normalizing these curves, the system can accurately identify the corresponding frosting degree after the resistance increase of the heat exchanger caused by frosting.

[0035] As Figure 2 shown, the graph depicts the fan characteristics applied to the finned heat exchanger, highlighting the system response during the transition from frost-free to frosted. Initially, the system operates in a frost-free state, and its resistance characteristics are represented by the first resistance curve. The operating point A lies on this curve, corresponding to a fan power of P1, which is the power requirement in the clean fin state. As frost begins to accumulate on the fin surface, the system resistance curve shifts to the second resistance curve, and the operating point migrates to point B. At this moment, the required fan power increases to P2, reflecting the increased energy consumption caused by frosting. Pmin indicates the minimum power level at which the fan operates.

[0036] To standardize the assessment of the severity of frosting, a normalization processing formula is introduced to define the frosting degree ε: ε = (|P1 - P2|) / (P1 - Pmin).

[0037] Here, the larger the value of ε, the heavier the frosting. The system preset threshold monitors ε. Once it exceeds the set condition, a defrosting alarm is triggered, and defrosting operation strategies such as four-way valve turning and hot gas bypass are executed to ensure the heat exchanger efficiency and the stable operation of the system.

[0038] According to a defrosting system of a finned heat exchanger provided by the present invention, the data processing module further includes: a defrosting operation unit configured to perform a defrosting operation when the frosting degree reaches a preset condition. Specifically, when the system determines through the previously mentioned frosting degree index ε that the frost accumulation on the fins has reached a preset threshold, it indicates that frosting has affected the heat exchange efficiency or increased the system load excessively (manifested as the fan power P2 being significantly higher than P1 without frost). At this time, the defrosting operation unit automatically starts the defrosting program. The defrosting measures may include activating a four-way valve to change the refrigerant flow direction, implementing hot gas bypass to utilize the system's own heat to melt the frost layer, or adopting other effective physical or thermal methods, aiming to quickly and safely remove the frost on the fins and restore the optimal working state of the heat exchanger.

[0039] The following combines Figure 3 to describe the defrosting method of the finned heat exchanger provided by the present invention. The defrosting method of the finned heat exchanger described below can be mutually referred to corresponding to the defrosting system of the finned heat exchanger described above. The defrosting method of the finned heat exchanger is a specific application of the above system. This method is based on a comprehensive analysis of environmental monitoring data, refrigerant outlet temperature parameters, and fan power changes to make a defrosting decision.

[0040] The present invention also provides a defrosting method for a finned heat exchanger, which is used for the defrosting system of the finned heat exchanger in any of the above embodiments. This method ensures that when there are signs of frosting on the fin heat exchanger, it can be identified and the defrosting process can be started in a timely and accurate manner. The specific steps include: obtaining the power change amount of the fan; determining the frosting degree of the finned heat exchanger based on the power change amount; and performing a defrosting operation when the frosting degree reaches a preset condition.

[0041] Specifically, the system continuously tracks the power consumption of the fan because frosting will cause an increase in wind resistance, and thus the fan needs to consume more power to maintain the set air volume. By analyzing the change trend of the fan power, it can indirectly judge whether frosting has started or accumulated on the fins; combining the analysis results of temperature and humidity parameters, outlet temperature parameters, and fan power changes, the judgment unit makes a decision on whether frosting has occurred. If the comparison of the environmental temperature and humidity with the fin outlet temperature parameters and the abnormal change of the fan power both indicate frosting, the frosting state can be confirmed.

[0042] Through the calculation unit, algorithms such as normalization processing are used to further quantify the frosting degree ε to ensure the accuracy of the judgment; when the frosting degree evaluated by the system reaches a preset threshold, that is, when it is considered to have affected the heat exchange efficiency or the safe operation of the equipment, the defrosting operation unit automatically intervenes. This may include, but is not limited to, switching the direction of the four-way valve, enabling a hot gas bypass cycle, briefly stopping the refrigeration cycle and other strategies to heat the fins and melt the frost, and restore the heat exchange efficiency.

[0043] A defrosting method for a finned heat exchanger provided by the present invention preferably further includes, before the step of obtaining the power change amount of the fan: obtaining the refrigerant outlet temperature parameter of the finned heat exchanger; in the case where the refrigerant outlet temperature parameter is lower than the dew point temperature of the current environment, determining that the finned heat exchanger has a frosting possibility. Monitoring the refrigerant outlet temperature parameter of the finned heat exchanger through a temperature sensor, which is a direct indicator for evaluating whether frosting occurs. Because when the outlet temperature parameter drops below the dew point, the frosting risk increases significantly. At this time, based on the power change amount, determining the frosting degree of the finned heat exchanger can make a more accurate judgment on the frosting state and prevent misjudgment of the system caused by the change of the fan power due to other factors.

[0044] Among them, through multi-dimensional data fusion and comparison analysis, this method improves the accurate evaluation ability of the working environment of the finned heat exchanger, ensures that when judging whether defrosting operation is required, it can be based on sufficient and reliable information, and avoids misoperation caused by the deviation of single-aspect data, thereby improving the defrosting efficiency and the operation efficiency of the entire system. The system can use the integrated temperature and humidity detection module to monitor and collect the temperature and humidity parameters of the current environment in real time, which includes the temperature and humidity levels inside and outside the room, providing a basis for subsequent analysis, such as for determining the dew point temperature of the current environment.

[0045] Further, before the step of obtaining the power change amount of the fan, it preferably further includes: receiving the temperature and humidity parameters from the temperature and humidity detection module; receiving the weather parameters from the network data acquisition module; and determining the dew point temperature of the current environment based on the temperature and humidity parameters and the weather parameters.

[0046] Specifically, the system uses the temperature and humidity detection module installed on site to directly collect the real-time temperature and humidity parameters of the current operating environment. At the same time, the system also accesses the meteorological service or network database through the network data acquisition module to download the temperature and humidity parameters of the weather forecast at the current location or nearby areas. Carefully compare the real-time data from the temperature and humidity detection module with the weather forecast data obtained through the network to confirm whether there is consistency between the two. If the two sets of data are close, it can be considered that the current environmental temperature and humidity conditions match the forecast, enhancing the credibility of the environmental judgment. If significant differences are found, further analysis may be required to determine whether there are individual factors affecting the local environment, such as local microclimate effects.

[0047] The temperature parameter of the refrigerant outlet is accurately measured by a temperature sensor installed at the outlet of the condenser. After confirming the relationship between the refrigerant outlet temperature parameter and the dew point temperature, further comprehensive analysis is carried out by combining the temperature and humidity parameters with the data of the condenser outlet temperature parameter. By combining the temperature and humidity parameters with the outlet temperature parameter data, various factors such as environmental humidity, temperature change trend, and the working state of the fin heat exchanger are comprehensively considered, so as to give a comprehensive assessment of the frosting risk. Through this multi-level and multi-parameter analysis method, the present invention can more accurately identify the early signs of frosting, avoid false alarms or missed alarms that may be caused by single-parameter judgment, and thus improve the timeliness and efficiency of the defrosting operation of the fin heat exchanger.

[0048] According to a defrosting method of a fin heat exchanger provided by the present invention, the steps of obtaining the power change amount of the fan include: obtaining the instant power feature and the instant operation mode of the fan, where the instant power feature is the change feature of the power of the fan within the acquisition time period; when the instant power feature conforms to the instant operation mode, determining the power change trend of the fan based on the adjacent N instant power features, and determining the power change amount according to the power change trend. By analyzing the power change amount, the severity of frosting on the fin heat exchanger can be indirectly deduced. Because frosting will increase the air duct resistance, resulting in the fan needing to increase the power output to maintain the original air volume. By establishing a mathematical model between the fan power and the frosting degree, the system can quantify the severity of frosting, that is, determine the frosting degree ε.

[0049] According to a defrosting method of a fin heat exchanger provided by the present invention, the steps of performing a defrosting operation when the frosting degree reaches a preset condition include: calculating the real-time frosting degree and comparing it with a preset threshold; when the frosting degree exceeds the preset threshold, starting the defrosting program. Specifically, the preset threshold represents the degree of frosting of the fin heat exchanger when defrosting must be carried out to ensure the normal operation and efficiency of the equipment. The real-time calculated frosting degree will be compared with this preset threshold. Once the calculated frosting degree exceeds the preset threshold, the system will automatically start the defrosting program. The defrosting program includes but is not limited to changing the refrigerant flow direction to heat the fins (such as switching the four-way valve), enabling the hot gas bypass cycle, or briefly stopping the refrigeration operation, etc., to heat the fins and melt the accumulated frost layer, and restore the heat exchange efficiency of the heat exchanger.

[0050] According to a defrosting method of a fin heat exchanger provided by the present invention, the step of starting the defrosting program further includes: sending a defrosting instruction to the defrosting operation unit; adjusting the four-way valve and / or the hot gas bypass to perform the defrosting operation; resetting the system state to the normal heating mode after completing the defrosting operation.

[0051] Specifically, when the system determines that the frosting degree reaches the preset condition, it automatically issues an instruction to the defrosting operation unit through the control logic. After receiving the instruction, the defrosting operation unit takes specific actions, including but not limited to adjusting the position of the four-way valve. The switching of the four-way valve can change the flow direction of the refrigerant, making the condenser become the evaporator, and using the heat of the refrigeration system itself to melt the frost layer on the fins. In addition, the hot gas bypass may also be opened to allow a part of the high-temperature gas to bypass the expansion valve and directly enter the evaporator to further accelerate the defrosting process. After the defrosting process is completed, the system automatically monitors and confirms that the frost layer on the fins has been completely removed. Subsequently, the control logic will reset the system parameters, such as restoring the four-way valve to its original working position and closing the hot gas bypass, to ensure that the system returns to the normal heating mode operation. The automatic reset function ensures the seamless connection of the defrosting operation, does not affect the user's comfort experience, reduces the need for manual intervention, and improves the reliability and convenience of the system.

[0052] The present invention also provides an outdoor unit of an air conditioner, which integrates a defrosting system of the finned heat exchanger according to any one of the above embodiments; and / or, when performing defrosting, the outdoor unit of the air conditioner adopts the defrosting method of the finned heat exchanger according to any one of the above embodiments.

[0053] Preferably, according to the defrosting system and defrosting method of the finned heat exchanger of the present invention, when the outdoor unit of the air conditioner is operating in the heating mode, the system first obtains the temperature and humidity conditions of the current and surrounding environments through the integrated temperature and humidity detection module and the networked data service, and calculates the dew point temperature based on this data. If the monitored value of the refrigerant outlet temperature parameter of the finned heat exchanger is lower than the calculated dew point, the system will automatically start the dynamic monitoring program for the fan power. This includes previously recording and storing the fan reference power in the frost-free state of the finned heat exchanger, and then continuously tracking and analyzing the power change in real time, and using this data to estimate the frosting degree ε.

[0054] Once the calculated frosting degree ε breaks through the preset threshold, it indicates that the frost accumulation on the fins has reached the degree that needs to be processed. At this time, the defrosting system will be automatically activated. The response measures may include adjusting the direction of the four-way valve to change the refrigerant circulation path, or opening the hot gas bypass circulation to use the internal heat of the system to melt the frost layer on the fins. On the contrary, if the frosting degree does not reach the threshold, the system will maintain the current operating mode, avoiding unnecessary defrosting operations and ensuring the energy efficiency and economic operation of the system.

[0055] In summary, through the integrated intelligent defrosting system and method, the outdoor unit of the air conditioner of the present invention realizes the accurate judgment and timely treatment of the frosting condition of the finned heat exchanger, not only improves the operating efficiency and reliability of the equipment, but also effectively avoids energy waste and enhances the user experience.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A defrosting system for a finned heat exchanger, characterized in that, Comprising: A fan parameter monitoring module configured to monitor the power change of the fan in real time; A data processing module configured to analyze the power change of the fan to determine whether the finned heat exchanger is frosted and perform a defrosting operation.

2. The defrosting system of the finned heat exchanger according to claim 1, characterized in that, The data processing module includes a calculation unit configured to calculate the degree of frosting according to the power change of the fan, and when the degree of frosting reaches a preset condition, it reminds that defrosting is required.

3. The defrosting system of the finned heat exchanger according to claim 2, characterized in that, The calculation unit further includes a normalization processing subunit configured to generate a characteristic curve of the fan, perform normalization processing on the characteristic curve, and obtain the degree of frosting; The characteristic curve includes: a fan curve in which the total pressure of the fan changes with the air flow rate at the rated speed of the fan, a power curve in which the power of the fan changes with the air flow rate, a first resistance curve of the finned heat exchanger changing with the air flow rate under normal conditions, and a second resistance curve of the finned heat exchanger changing with the air flow rate in the frosted state.

4. The defrosting system of the finned heat exchanger according to claim 3, wherein, The data processing module further includes a defrosting operation unit configured to perform a defrosting operation when the degree of frosting reaches a preset condition.

5. The defrosting system of the finned heat exchanger according to any one of claims 1-4, characterized in that, Comprising: A temperature and humidity detection module configured to obtain the temperature and humidity parameters of the current environment; A temperature sensor configured to detect the refrigerant outlet temperature parameter of the finned heat exchanger; The data processing module further includes: A comparison unit configured to compare the refrigerant outlet temperature parameter with the dew point temperature corresponding to the temperature and humidity parameters; A judgment unit configured to determine that the finned heat exchanger will be frosted when the refrigerant outlet temperature parameter is lower than the dew point temperature.

6. The defrosting system of the finned heat exchanger according to claim 5, characterized in that, Including a networked data acquisition module configured to acquire the weather parameters of the current location; The comparison unit is configured to compare the temperature and humidity parameters with the weather parameters to determine the dew point temperature of the current environment.

7. A defrosting method for a finned heat exchanger, characterized in that, A defrosting system for the finned heat exchanger according to any one of claims 1-5, comprising: Obtaining the power change of the fan; Based on the power change, determining the degree of frosting of the finned heat exchanger; Performing a defrosting operation when the degree of frosting reaches a preset condition.

8. The defrosting method of the finned heat exchanger according to claim 7, characterized in that, The step of obtaining the power change of the fan includes: Obtaining the instantaneous power characteristic and the instantaneous operation mode of the fan, where the instantaneous power characteristic is the change characteristic of the power of the fan within the acquisition time period; When the instantaneous power characteristic conforms to the instantaneous operation mode, determining the power change trend of the fan based on adjacent N instantaneous power characteristics, and determining the power change amount according to the power change trend.

9. The defrosting method of the finned heat exchanger according to claim 7, characterized in that, The step of performing a defrosting operation when the degree of frosting reaches a preset condition includes: Calculating the real-time degree of frosting and comparing it with a preset threshold; When the degree of frosting exceeds the preset threshold, starting a defrosting program.

10. The defrosting method of the finned heat exchanger according to claim 7, characterized in that, Before the step of obtaining the power change of the fan, it further includes: Obtaining the refrigerant outlet temperature parameter of the finned heat exchanger; When the refrigerant outlet temperature parameter is lower than the dew point temperature of the current environment, determining that the finned heat exchanger has a possibility of frosting.

11. The defrosting method of the finned heat exchanger according to claim 10, characterized in that, Before the step of obtaining the power change of the fan, it further includes: Receiving the temperature and humidity parameters from the temperature and humidity detection module; Receive weather parameters from the networked data acquisition module; Determine the dew point temperature of the current environment based on the temperature and humidity parameters and the weather parameters.

12. An outdoor unit of an air conditioner, characterized in that, When defrosting is performed, use the defrosting method of the finned heat exchanger described in any one of claims 7-11 above.

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