A control method, device, storage medium, and air conditioner for an air conditioner

Abstract

This invention provides a control method, device, storage medium, and air conditioner for an air conditioner. The method includes: after the air conditioner is turned on for heating and enters anti-cold air control, determining whether the air conditioner meets the conditions for exiting anti-cold air control and whether it is in the compressor frequency dwell control stage; when it is determined that the conditions for exiting anti-cold air control are met and the air conditioner is in the compressor frequency dwell control stage, determining whether the indoor heat exchanger tube temperature is less than or equal to a second preset temperature value; if it is determined that the indoor heat exchanger tube temperature is less than or equal to the second preset temperature value, increasing the opening degree of the air conditioner's throttling element according to the temperature rise rate of the indoor heat exchanger tube temperature; after increasing the opening degree of the air conditioner's throttling element, determining whether liquid compression has occurred according to the compressor's suction superheat; if it is determined that liquid compression has occurred in the air conditioner's compressor, decreasing the opening degree of the air conditioner's throttling element to increase the compressor's suction superheat. The solution provided by this invention can improve the reliability of the compressor.

Description

TECHNICAL FIELD

[0001] The present application relates to the control field, and particularly to an air conditioner control method and device, a storage medium and an air conditioner. BACKGROUND

[0002] When a heat pump air conditioner is used for heating in winter, the higher the outdoor ambient temperature, the higher the requirements for air conditioner operation reliability and comfort. On the one hand, the air conditioner operates at high load under low temperature conditions, and the oil return state of the air conditioner system is poor, which can easily cause oil starvation or oil starvation of the compressor, reducing the reliability and service life of the air conditioner. On the other hand, the heating temperature rise rate of the air conditioner under low temperature conditions is slow, and the outlet air temperature is low when the air conditioner is just started, which can cause cold air blowing and user discomfort.

[0003] In related technologies, a frequency stay platform is set during the compressor startup and frequency increase process, so that the air conditioner maintains a certain frequency for a certain period of time before continuing to increase the frequency, to improve the oil return of the compressor and improve the reliability of the air conditioner under low temperature conditions. At the same time, a cold air prevention control function is designed, and the indoor fan is started after the indoor temperature of the air conditioner rises to a certain value, so as to ensure that the outlet air temperature of the air conditioner is not too low and improve user comfort. However, the above technical solution has the following problems:

[0004] The compressor oil return reliability control technology and the cold air prevention control technology lack coupled control, and the method for ensuring the reliability of the air conditioner is single, relying only on the frequency stay control technology during the compressor frequency increase stage, which restricts the air conditioner's early heating capacity output and causes the air conditioner to be unable to quickly blow hot air. SUMMARY

[0005] The main purpose of the present application is to overcome the defects of the above related technologies, and to provide an air conditioner control method, device, storage medium and air conditioner to solve the problem of reduced system reliability of the air conditioner in the related art under large heat output conditions.

[0006] The application provides a control method of an air conditioner, comprising: after the air conditioner is started and enters a cold-wind prevention control, judging whether the air conditioner meets a condition for exiting the cold-wind prevention control and whether the air conditioner is in a compressor frequency stay control stage; the compressor frequency stay control refers to maintaining the compressor at a set frequency for a set time in a frequency increasing process after the compressor is started, and then continuing to increase the frequency; the set frequency is recorded as a stay point frequency of the compressor frequency stay control, and the set time is recorded as a stay time length of the compressor frequency stay control; when it is judged that the air conditioner meets the condition for exiting the cold-wind prevention control and the air conditioner is in the compressor frequency stay control stage, judging whether an indoor heat exchanger pipe temperature of the air conditioner is less than or equal to a second preset temperature value; if it is judged that the indoor heat exchanger pipe temperature is less than or equal to the second preset temperature value, increasing an opening degree of a throttling element of the air conditioner according to a temperature rise rate of the indoor heat exchanger pipe temperature, wherein the increased opening degree of the throttling element is recorded as a first opening degree, and the increased opening degree is equal to an increased opening degree minus a previous opening degree; after the opening degree of the throttling element of the air conditioner is increased, judging whether the compressor of the air conditioner occurs liquid compression according to a suction superheat degree of the compressor of the air conditioner; if it is judged that the compressor of the air conditioner occurs liquid compression, decreasing the opening degree of the throttling element of the air conditioner to improve the suction superheat degree of the compressor, wherein the decreased opening degree of the throttling element is recorded as a second opening degree, and the decreased opening degree is equal to a previous opening degree minus a decreased opening degree.

[0007] Optionally, the determining whether the air conditioner meets the condition for exiting the anti-cold blast control comprises: determining whether a temperature of an indoor heat exchanger of the air conditioner is greater than or equal to a first preset temperature value, and if the temperature of the indoor heat exchanger is greater than or equal to the first preset temperature value, determining that the air conditioner meets the condition for exiting the anti-cold blast control; and / or determining whether the air conditioner is in a compressor frequency staying control stage, comprising: if a cumulative running time of a compressor of the air conditioner is greater than a preset time length and less than or equal to a sum of the cumulative running time of the compressor when entering the compressor frequency staying control and a staying time length of the compressor frequency staying control, determining that the air conditioner is in the compressor frequency staying control stage; and / or increasing an opening degree of a throttling element of the air conditioner according to a temperature rising rate of the indoor heat exchanger, comprising: determining an interval in which the temperature rising rate of the indoor heat exchanger is located among two or more preset temperature rising rate intervals, wherein each of the two or more preset temperature rising rate intervals corresponds to an opening degree increment; determining the opening degree increment of the throttling element of the air conditioner according to the opening degree increment corresponding to the interval in which the temperature rising rate of the indoor heat exchanger is located among the two or more preset temperature rising rate intervals; and increasing the opening degree of the throttling element of the air conditioner according to the determination of the opening degree increment of the throttling element of the air conditioner; and / or determining whether the compressor of the air conditioner is in liquid compression according to a suction superheat degree of the compressor, comprising: determining whether the compressor of the air conditioner is in liquid compression according to a size relationship between the suction superheat degree of the compressor and a preset superheat degree value; wherein if the suction superheat degree is less than or equal to the preset superheat degree value, it is determined that the compressor is in liquid compression, and if the suction superheat degree is greater than the preset superheat degree value, it is determined that the compressor is not in liquid compression.

[0008] Optionally, further comprising: when it is judged that the air conditioner meets the condition for exiting the anti-cold-wind control but the air conditioner is not in the compressor frequency staying control stage, controlling the air conditioner to maintain the current state of heating operation; wherein the condition that the air conditioner is not in the compressor frequency staying control stage includes: the cumulative running time length of the compressor of the air conditioner is less than or equal to a preset time length, and / or the cumulative running time length of the compressor of the air conditioner is greater than the sum of the cumulative running time length of the compressor when entering the compressor frequency staying control and the staying time length of the compressor frequency staying control; and / or, when the air conditioner meets the condition for exiting the compressor frequency staying control, controlling the air conditioner to resume normal heating operation; the condition for exiting the compressor frequency staying control includes: the cumulative running time length of the compressor is greater than the sum of the cumulative running time length of the compressor when entering the compressor frequency staying control and the staying time length of the compressor frequency staying control; and / or, if it is judged that the compressor of the air conditioner is in liquid compression, judging the size relationship between the opening degree difference value between the first opening degree and the second opening degree and a preset opening degree difference value after reducing the opening degree of the throttling element of the air conditioner; if the opening degree difference value between the first opening degree and the second opening degree is less than or equal to the preset opening degree difference value, adjusting the compressor frequency according to the current suction pressure of the compressor and the temperature rise rate of the indoor heat exchanger pipe; and / or, if it is judged that the compressor of the air conditioner is not in liquid compression, correcting the staying time length of the compressor frequency staying control according to the current opening degree of the throttling element of the air conditioner and the compressor frequency.

[0009] Optionally, the staying time length of the compressor frequency staying control is determined according to the outdoor environment temperature, including: determining the temperature interval in which the outdoor environment temperature is located among two or more preset temperature intervals; wherein each temperature interval among the two or more preset temperature intervals corresponds to a time length; determining the staying time length of the compressor frequency staying control currently performed by the air conditioner according to the time length corresponding to the temperature interval in which the outdoor environment temperature is located among the two or more preset temperature intervals; and / or, the cumulative running time length of the compressor when entering the compressor frequency staying control is determined according to the initial frequency of compressor start, the time length of the compressor start stage and the frequency rise rate of the compressor; wherein the calculation formula of the cumulative running time length s1 of the compressor when entering the compressor frequency staying control is as follows:

[0010] s1=(F1-F start ) / v+s other

[0011] wherein F1 is the staying point frequency of the compressor frequency staying control, F start is the initial frequency of compressor start, s otherHere, v represents the compressor start-up phase duration, and v represents the compressor's frequency ramp-up rate; and / or, it further includes: after adjusting the compressor frequency, resetting the first opening degree, so that if it is determined that the air conditioner's compressor is undergoing liquid compression, after reducing the opening degree of the air conditioner's throttling element, the relationship between the opening degree difference between the first opening degree and the second opening degree and the preset opening degree difference is determined again; and / or, based on the current throttling element opening degree and compressor frequency of the air conditioner, correcting the dwell time of the compressor frequency dwell control, including: determining the correction time based on the current throttling element opening degree and compressor frequency of the air conditioner, and correcting the dwell time of the compressor frequency dwell control based on the determined correction time; wherein, the corrected dwell time is equal to the current dwell time of the air conditioner's compressor frequency dwell control minus the correction time.

[0012] Another aspect of the present invention provides a control device for an air conditioner, comprising: a first judgment unit, configured to, after the air conditioner is turned on for heating and enters anti-cold air control, determine whether the air conditioner meets the conditions for exiting anti-cold air control and whether the air conditioner is in a compressor frequency dwell control stage; the compressor frequency dwell control refers to maintaining the compressor at a set frequency for a set time during the frequency increase process after the compressor starts, and then continuing to increase the frequency; the set frequency is recorded as the dwell point frequency of the compressor frequency dwell control, and the set time is recorded as the dwell duration of the compressor frequency dwell control; a second judgment unit, configured to, when the first judgment unit determines that the air conditioner meets the conditions for exiting anti-cold air control and the air conditioner is in the compressor frequency dwell control stage, determine whether the indoor heat exchanger pipe temperature of the air conditioner is less than or equal to a second preset temperature value; and a control unit, configured to, if ... The second judgment unit determines that the indoor heat exchanger tube temperature is less than or equal to a second preset temperature value, and then increases the opening degree of the air conditioner's throttling element according to the temperature rise rate of the indoor heat exchanger tube temperature, wherein the increased opening degree of the throttling element is recorded as the first opening degree, and the increased opening degree is equal to the increased opening degree minus the original opening degree; the third judgment unit is used to determine whether the air conditioner's compressor is undergoing liquid compression based on the suction superheat of the air conditioner's compressor after the control unit increases the opening degree of the air conditioner's throttling element; the control unit is further used to: if the third judgment unit determines that the air conditioner's compressor is undergoing liquid compression, then decrease the opening degree of the air conditioner's throttling element to increase the suction superheat of the compressor, wherein the decreased opening degree of the throttling element is recorded as the second opening degree, and the decreased opening degree is equal to the original opening degree minus the decreased opening degree.

[0013] Optionally, the first determining unit determines whether the air conditioner meets the conditions for exiting anti-cold air control, including: determining whether the indoor heat exchanger pipe temperature of the air conditioner is greater than or equal to a first preset temperature value; if the indoor heat exchanger pipe temperature is greater than or equal to the first preset temperature value, then the air conditioner is determined to meet the conditions for exiting anti-cold air control; and / or, the first determining unit determines whether the air conditioner is in the compressor frequency dwell control stage, including: if the cumulative compressor runtime of the air conditioner is greater than a preset duration, and less than or equal to the sum of the cumulative compressor runtime when entering compressor frequency dwell control and the dwell time of compressor frequency dwell control, then the air conditioner is determined to be in the compressor frequency dwell control stage; and / or, the control unit increases the opening of the throttling element of the air conditioner according to the temperature rise rate of the indoor heat exchanger pipe temperature, including: determining that the temperature rise rate of the indoor heat exchanger pipe temperature is at more than two preset temperature values. The interval within the temperature rise rate range, wherein each of the two or more preset temperature rise rate ranges corresponds to an opening increment; the opening increment of the throttling element of the air conditioner is determined based on the opening increment corresponding to the interval within the two or more preset temperature rise rate ranges where the temperature rise rate of the indoor heat exchanger tube temperature is located; the opening of the throttling element of the air conditioner is increased based on the determined opening increment of the throttling element of the air conditioner; and / or, the third judgment unit determines whether the compressor of the air conditioner has undergone liquid compression based on the suction superheat of the compressor of the air conditioner, including: determining whether the compressor of the air conditioner has undergone liquid compression based on the relationship between the suction superheat of the compressor and a preset superheat value; wherein, if the suction superheat is less than or equal to the preset superheat value, it is determined that the compressor has undergone liquid compression; if the suction superheat is greater than the preset superheat value, it is determined that the compressor has not undergone liquid compression.

[0014] Optionally, the control unit is further configured to: when it is determined that the air conditioner meets the conditions for exiting the anti-cold air control, but the air conditioner is not in the compressor frequency pause control stage, control the air conditioner to maintain its current heating operation; wherein, the situation where the air conditioner is not in the compressor frequency pause control stage includes: the cumulative running time of the air conditioner's compressor is less than or equal to a preset time, and / or the cumulative running time of the air conditioner's compressor is greater than the sum of the cumulative running time of the compressor when entering the compressor frequency pause control and the pause time of the compressor frequency pause control; and / or, the control unit is further configured to: when the air conditioner meets the conditions for exiting the compressor frequency pause control, control the air conditioner to resume normal heating operation; the conditions for exiting the compressor frequency pause control include: the cumulative running time of the compressor is greater than the cumulative running time of the compressor when entering the compressor frequency pause control. The control device further includes: a fourth judgment unit, configured to determine the relationship between the difference between the first opening degree and the second opening degree and a preset opening degree difference if the third judgment unit determines that the compressor of the air conditioner is undergoing liquid compression, after reducing the opening degree of the throttling element of the air conditioner; an adjustment unit, configured to adjust the compressor frequency according to the current suction pressure of the compressor and the temperature rise rate of the indoor heat exchanger pipe temperature if the fourth judgment unit determines that the difference between the first opening degree and the second opening degree is less than or equal to the preset opening degree difference; and / or, further includes: a correction unit, configured to correct the dwell time of the compressor frequency dwell control according to the current opening degree of the throttling element and the compressor frequency if the third judgment unit determines that the compressor of the air conditioner is not undergoing liquid compression.

[0015] Optionally, the control device further includes: a first determining unit, configured to determine the dwell time of the compressor frequency dwell control, wherein the dwell time of the compressor frequency dwell control is determined based on the outdoor ambient temperature, including: determining the temperature range in which the outdoor ambient temperature falls within two or more preset temperature ranges; wherein each of the two or more preset temperature ranges corresponds to a duration; determining the dwell time of the air conditioner currently performing compressor frequency dwell control based on the duration corresponding to the temperature range in which the outdoor ambient temperature falls within the two or more preset temperature ranges; and / or, the control device further includes: a second determining unit, configured to determine the cumulative compressor runtime when entering compressor frequency dwell control based on the compressor initial start frequency, the duration of the compressor start-up phase, and the compressor frequency ramp-up rate; wherein the calculation formula for the cumulative compressor runtime s1 when entering compressor frequency dwell control is as follows:

[0016] s1=(F1-F start ) / v+s other

[0017] Where F1 is the dwell point frequency of the compressor frequency dwell control, F start The initial starting frequency of the compressor is s. other Here, v represents the compressor start-up phase duration, and v represents the compressor's frequency ramp-up rate; and / or, the control device further includes: a reset unit, configured to reset the first opening degree after the adjustment unit adjusts the compressor frequency, so that when the third judgment unit determines that the air conditioner's compressor is undergoing liquid compression, after the control unit reduces the opening degree of the air conditioner's throttling element, the fourth judgment unit again determines the relationship between the opening degree difference between the first opening degree and the second opening degree and a preset opening degree difference; and / or, the correction unit, based on the current throttling element opening degree and compressor frequency of the air conditioner, corrects the dwell time of the compressor frequency dwell control, including: determining the correction time based on the current throttling element opening degree and compressor frequency of the air conditioner, and correcting the dwell time of the compressor frequency dwell control based on the determined correction time; wherein, the corrected dwell time is equal to the current dwell time of the air conditioner's compressor frequency dwell control minus the correction time.

[0018] In another aspect, the present invention provides a storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the methods described above.

[0019] In another aspect, the present invention provides an air conditioner, including a processor, a memory, and a computer program stored in the memory that can run on the processor, wherein the processor executes the program to implement the steps of any of the methods described above.

[0020] In another aspect, the present invention provides an air conditioner, including the control device for any of the aforementioned air conditioners.

[0021] According to the technical solution of this invention, when the anti-cold air operation is exited during heating and the system is in the frequency dwell control stage, the opening degree of the throttling element is adjusted based on the changes in the inner pipe temperature and the rate of change of the inner pipe temperature to increase the air conditioning capacity output and improve the system oil return. This can increase the air outlet temperature of the air conditioner and shorten the dwell time of constant frequency operation. At the same time, liquid compression is identified and controlled through the compressor suction dryness, and the frequency and throttling element opening are controlled in conjunction to increase the heat output of the air conditioner while avoiding liquid compression of the compressor, thus improving both user heating comfort and compressor operation reliability. While meeting the requirement of rapid hot air blowing during air conditioning heating, this solution addresses the problem of reduced air conditioning system reliability under high heat output conditions in existing air conditioners, achieving comfortable and reliable air conditioning operation and improving user experience.

[0022] According to the technical solution of the present invention, by using multiple parameters to comprehensively control the system reliability, the problem of poor heating comfort caused by the single reliability control method of the current compressor can be solved. While ensuring the air conditioner's high capacity output and rapid heating operation, reliability problems such as compressor oil shortage, oil-air shortage, or liquid compression are avoided, thereby maximizing user heating comfort and compressor lifespan. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0024] Figure 1 This is a schematic diagram of an embodiment of the air conditioner control method provided by the present invention;

[0025] Figure 2 A flowchart illustrating the steps of one specific implementation method is shown;

[0026] Figure 3 This is a schematic diagram of another embodiment of the air conditioner control method provided by the present invention;

[0027] Figure 4 This is a schematic diagram of another embodiment of the air conditioner control method provided by the present invention;

[0028] Figure 5 This is a schematic diagram of another embodiment of the air conditioner control method provided by the present invention;

[0029] Figure 6 This is the air conditioning operation control logic of the present invention;

[0030] Figure 7 This is the compressor reliability control logic according to the present invention;

[0031] Figure 8 This is a structural block diagram of an embodiment of the air conditioner control device provided by the present invention;

[0032] Figure 9 This is a structural block diagram of another embodiment of the air conditioner control device provided by the present invention;

[0033] Figure 10 This is a structural block diagram of another embodiment of the air conditioner control device provided by the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0036] The relevant technology incorporates a frequency pause platform during the compressor's start-up and frequency ramp-up process. This allows the air conditioner to maintain a certain frequency for a specific period before continuing to ramp up, improving oil return in the compressor and enhancing the reliability of low-temperature operation. Simultaneously, a heating anti-cold air control function is designed, ensuring that the indoor fan only activates after the compressor starts and the internal pipe temperature reaches a certain value, thus preventing the air conditioner's outlet temperature from becoming too low and improving user comfort.

[0037] However, the above technical solutions have the following problems: the compressor oil return reliability control technology and the anti-cold air control technology lack coupled control, and the method to ensure the reliability of the air conditioner is singular, relying solely on the compressor frequency standby control technology during the frequency boosting phase. This restricts the air conditioner's output capacity in the early heating stage, causing the air conditioner to fail to quickly blow hot air. Furthermore, when the compressor frequency standby control occurs after the anti-cold air control is disengaged, there is still a risk of blowing cold air, affecting the user experience. This is because during the low-temperature heating start-up frequency boosting phase of the air conditioner, the initial room temperature is low, while the air conditioner's heat output is low and the internal pipe temperature rises slowly. Directly turning on the internal fan at this time will cause the outlet air temperature to drop rapidly. Therefore, the internal pipe temperature needs to be higher than the target pipe temperature (e.g., 40℃) to restore normal operating fan speed. However, when the internal pipe temperature is just above the target pipe temperature, but the compressor is in the frequency dwell phase, the air conditioner's heat output does not increase in real time, while the internal fan speed increases rapidly. This causes the internal pipe temperature and the outlet air temperature to drop continuously, resulting in poor anti-cold air effect. For example, in the heating operation under the condition of 0℃ internal temperature and -5℃ external temperature, the relevant technical solution enters frequency dwell control after the compressor has accumulated 160 seconds of operation, and exits the air conditioner's anti-cold air function at 190 seconds. At this time, the internal pipe temperature drops rapidly from 40℃ to 28℃, and the outlet air temperature drops to 18℃~20℃, resulting in a low outlet air temperature.

[0038] This invention provides a method for controlling an air conditioner.

[0039] Figure 1 This is a schematic diagram of an embodiment of the air conditioner control method provided by the present invention.

[0040] like Figure 1 As shown, according to an embodiment of the present invention, the control method includes at least steps S110, S120, S130, S140 and S150.

[0041] Step S110: After the air conditioner is turned on for heating and enters the anti-cold air control, determine whether the air conditioner meets the conditions for exiting the anti-cold air control and whether the air conditioner is in the compressor frequency dwell control stage.

[0042] The compressor frequency dwell control refers to maintaining the compressor at a set frequency for a set time during the frequency increase process after the compressor starts, and then continuing to increase the frequency; the set frequency is recorded as the dwell point frequency of the compressor frequency dwell control, and the set time is recorded as the dwell duration of the compressor frequency dwell control.

[0043] In one specific implementation, determining whether the air conditioner meets the conditions for exiting anti-cold air control includes: determining the indoor heat exchanger tube temperature T of the air conditioner. s If the temperature is greater than or equal to the first preset temperature value T1, then the indoor heat exchanger tube temperature T is determined. sIf the temperature is greater than or equal to the first preset temperature value T1, then the air conditioner is determined to meet the conditions for exiting the anti-cold air control.

[0044] Specifically, the temperature of the indoor heat exchanger tubes (referred to as the inner tube temperature) T is detected and recorded in real time. s Determine the temperature T of the indoor heat exchanger tubes in the air conditioner. s The relationship with the preset temperature value T1 is that the first preset temperature value T1 is the target internal pipe temperature of the indoor heat exchanger when the anti-cold air control is lifted. If T s If the temperature is less than T1, meaning the indoor heat exchanger pipe temperature is low and the air outlet temperature is low, then the indoor fan should remain off or running at low speed to prevent direct cold airflow; if T... s If the temperature is greater than or equal to T1, meaning the temperature of the indoor heat exchanger tube is high enough to meet the conditions for exiting the anti-cold air control, then the anti-cold air control will be exited and the indoor fan will switch to the set fan speed.

[0045] In one specific implementation, determining whether the air conditioner is in the compressor frequency dwell control stage includes: if the cumulative running time s of the air conditioner's compressor is greater than the preset time s0, and less than or equal to the sum of the cumulative running time s1 of the compressor when entering the compressor frequency dwell control and the dwell time t of the compressor frequency dwell control, then the air conditioner is determined to be in the compressor frequency dwell control stage.

[0046] When the air conditioner is turned on for heating, it enters anti-cold air control mode, the indoor fan is turned off or runs at the set low speed, and the outdoor ambient temperature T is detected and recorded. w Indoor ambient temperature T n Calculate the temperature difference between indoor and outdoor environments (referred to as indoor-outdoor temperature difference): ΔT = T n -T w According to the outdoor ambient temperature T w The temperature difference ΔT between indoor and outdoor ambient temperatures determines the dwell point frequency F1 of the compressor frequency dwell control, based on the outdoor ambient temperature T. w Determine the dwell time t for compressor frequency dwell control. This dwell time is the duration during which the compressor frequency is maintained at the frequency dwell point when performing compressor frequency dwell control; the dwell point frequency F1 = c1T. w +c2ΔT+c3, where c1, c2, and c3 are fitting coefficients, obtained by designing orthogonal verification experiments to fit the data.

[0047] The dwell time t of the compressor frequency dwell control is based on the outdoor ambient temperature T. w To determine, determine the outdoor ambient temperature T. w The temperature range is located within one or more preset temperature ranges, where each of the preset temperature ranges corresponds to a duration, i.e., based on the outdoor ambient temperature T. wThe dwell time t of the air conditioner when performing compressor frequency dwell control is determined by the duration corresponding to the temperature range in one or more preset temperature ranges.

[0048] For example, ① when T w When A < T, the corresponding stay duration is t1; ② When A ≤ T w When ≤ B, the corresponding dwell time is t2; ③ When T w When A = -7℃ and B = 18℃, the corresponding dwell time is t3; for example, when A = -7℃ and B = 18℃, t1, t2, and t3 are 120s, 30s, and 0s, respectively.

[0049] When the outdoor ambient temperature T w When the temperature is lower and the indoor-outdoor temperature difference ΔT is larger, the system oil return condition is poor. Therefore, the compressor residence point frequency F1 is lower and the residence time t is longer, which makes the compressor oil discharge rate lower and the oil return time longer, thus improving the system oil return.

[0050] Preferably, the dwell frequency F1 of the compressor frequency dwell control is determined to be different from the preset minimum value of the compressor dwell frequency F. min The relationship when F1 < F min Then F1 takes F min To avoid a slow compressor oil return rate that could reduce air conditioner reliability. When the outdoor ambient temperature T w The higher the temperature and the smaller the indoor-outdoor temperature difference ΔT, the better the system's oil return condition. This results in a higher compressor dwell point frequency F1, a shorter dwell time t, greater heating output, and a faster indoor temperature rise rate. The relationship between F1 and the maximum dwell point frequency F of the compressor frequency dwell control is determined. max The relationship when F1 > F max Then F1 takes F max This prevents the compressor from over-discharged oil, which could lead to oil shortage or oil depletion in the system, thus ensuring the reliability of the air conditioner's operation.

[0051] The cumulative running time s1 of the compressor when entering the compressor frequency dwell control is determined based on the initial compressor start-up frequency, the duration of the compressor start-up phase, and the compressor frequency ramp-up rate.

[0052] In one specific implementation, the formula for calculating the cumulative compressor runtime s1 when entering compressor frequency dwell control is as follows:

[0053] s1=(F1-F start ) / v+s other

[0054] Where F1 is the dwell point frequency of the compressor frequency dwell control, F start The initial starting frequency (Hz) of the compressor, s otherThe duration of the compressor start-up phase can include, for example, compressor standby time (i.e., compressor standby start-up time), compressor start-up protection control time, compressor AC current or module current or overload protection frequency limiting time; v is the compressor frequency ramp-up rate, which is a fixed parameter value.

[0055] When the air conditioner meets the conditions for exiting the anti-cold air control, the current cumulative compressor running time s is detected, and the relationship between the cumulative compressor running time s and the preset time s0 and the cumulative running time s1 at the compressor frequency dwell point is determined. If the cumulative compressor running time s of the air conditioner is greater than the preset time s0, and less than or equal to the sum of the cumulative compressor running time s1 when entering the compressor frequency dwell control and the dwell time t of the compressor frequency dwell control, that is, s is greater than s0 and less than or equal to (s1+t), that is, when the air conditioner reaches the target indoor pipe temperature condition for exiting the anti-cold air control, it just enters or is in the compressor frequency dwell control stage. At this time, exiting the anti-cold air control will cause the indoor heat exchanger pipe temperature and the outlet air temperature to drop rapidly, so the compressor reliability control is entered to improve the heat output of the air conditioner.

[0056] When it is determined that the air conditioner meets the conditions for exiting anti-cold air control, but the air conditioner is not in the compressor frequency dwell control stage, the air conditioner is controlled to maintain its current heating operation. The situation where the air conditioner is not in the compressor frequency dwell control stage includes: the cumulative running time of the air conditioner's compressor is less than or equal to a preset duration, and / or the cumulative running time of the air conditioner's compressor is greater than the sum of the cumulative running time of the compressor when entering compressor frequency dwell control and the dwell time of compressor frequency dwell control.

[0057] That is, if the cumulative running time s of the air conditioner compressor is less than or equal to the preset time s0, it indicates that the current room temperature is high, the load is low, and the temperature rise rate is fast, making it difficult to blow cold air. Therefore, the air conditioner will maintain normal heating operation. Before the compressor starts, the indoor heat exchanger tube temperature is similar to the room temperature. During the start-up phase, if the indoor heat exchanger tube temperature rise rate is faster than a certain value, meaning the time to reach the exit condition is less than the preset time s0, it indicates that the room temperature is high and it is difficult to blow cold air. The preset time s0 can be measured experimentally or obtained based on the required indoor tube temperature rise rate. If the cumulative running time s of the air conditioner compressor is greater than the sum of the cumulative running time s1 of the compressor when entering compressor frequency dwell control and the dwell time t of compressor frequency dwell control, i.e., s is greater than (s1+t), the compressor has exited frequency dwell control, and the air conditioner is in the compressor frequency increase phase, with the heating capacity continuously increasing. Therefore, the air conditioner will maintain normal heating operation.

[0058] Step S120: When it is determined that the air conditioner meets the conditions for exiting the anti-cold air control and the air conditioner is in the compressor frequency dwell control stage, it is determined whether the indoor heat exchanger tube temperature of the air conditioner is less than or equal to the second preset temperature value.

[0059] Specifically, when it is determined that the air conditioner meets the conditions for exiting anti-cold air control and the air conditioner is in the compressor frequency dwell control stage, the compressor reliability control is entered, i.e., steps S120 to S150. After entering compressor reliability control, the indoor heat exchanger tube temperature T of the air conditioner is detected. s Determine the indoor heat exchanger tube temperature T s The relationship between T and the second preset temperature value T2. If T s If the temperature is greater than T2, meaning the internal pipe temperature drops slowly after resuming normal fan speed and the outlet air temperature remains high, then continue operating in the current state; if T... s If the temperature is less than or equal to T2, the internal pipe temperature and the outlet air temperature will drop rapidly after the fan speed is restored to normal, which may pose a risk of blowing cold air.

[0060] Step S130: If it is determined that the indoor heat exchanger tube temperature is less than or equal to the second preset temperature value, then the opening degree of the throttling element of the air conditioner is increased according to the temperature rise rate of the indoor heat exchanger tube.

[0061] The throttling element can specifically be a throttling element between the indoor and outdoor heat exchangers of an air conditioner. For example, by acquiring the temperature change value of the indoor heat exchanger tube temperature every n seconds, the temperature rise rate of the indoor heat exchanger tube temperature can be calculated.

[0062] Figure 2 A flowchart illustrating the steps of one specific implementation is shown. Figure 2 As shown, in one specific embodiment, step S130 includes steps S131, S132 and S133.

[0063] Step S131: Determine the temperature rise rate of the indoor heat exchanger tube within one of two or more preset temperature rise rate ranges.

[0064] Step S132: Determine the opening increment of the throttling element of the air conditioner based on the opening increment corresponding to the interval in which the temperature rise rate of the indoor heat exchanger tube is located in the two or more preset temperature rise rate intervals.

[0065] Step S133: Increase the opening degree of the throttling element of the air conditioner according to the determined opening degree increment of the throttling element of the air conditioner.

[0066] Wherein, each of the two or more preset temperature rise rate intervals corresponds to an opening increment; that is, the opening increment corresponding to the interval in which the temperature rise rate of the indoor heat exchanger tube temperature is located in the two or more preset temperature rise rate intervals is determined as the opening increment of the throttling element of the air conditioner. The increased opening degree of the throttling element (i.e., the opening increment, the increased opening degree is equal to the increased opening degree minus the original opening degree) is denoted as the first opening degree.

[0067] For example, the rate of temperature rise v of the indoor heat exchanger tubes. T When v T When the temperature is less than v1, meaning the inner tube temperature drops too quickly, increase the opening of the electronic expansion valve Δk1; when v1 ≤ v T When v ≤ v2, meaning the inner tube temperature drops slowly, increase the opening of the electronic expansion valve Δk2, where Δk1 > Δk2; when v T When the value is greater than v2, that is, the inner tube temperature drops very slowly or the tube temperature rises, the opening increment of the electronic expansion valve is 0.

[0068] In another specific embodiment, based on the indoor heat exchanger tube temperature v T According to a preset formula for calculating the opening increment, the opening increment Δk1 of the air conditioner's throttling element is determined; based on the determined opening increment Δk1, the opening of the air conditioner's throttling element is increased. The increased opening of the throttling element (i.e., the opening increment) is recorded as the first opening. The formula for calculating the opening increment is: Δk1 = c4v T +c5; where c4 and c5 are fitting coefficients, which can be obtained by designing orthogonal validation experiments to fit the data.

[0069] Step S140: After increasing the opening of the throttling element of the air conditioner, determine whether the compressor of the air conditioner is undergoing liquid compression based on the suction superheat of the compressor of the air conditioner.

[0070] The compressor's suction temperature Ti and suction pressure Pi are detected. The saturation temperature corresponding to the suction pressure Pi is looked up. The suction superheat ΔTi of the compressor is obtained by the difference between the suction temperature Ti and the saturation temperature corresponding to the suction pressure. Therefore, the compressor's suction superheat ΔTi is used to determine whether the air conditioner's compressor is undergoing liquid compression.

[0071] In one specific embodiment, whether the air conditioner compressor is undergoing liquid compression is determined based on the relationship between the compressor's suction superheat ΔTi and a preset superheat value ε. If the suction superheat is less than or equal to the preset superheat value ε, then liquid compression is determined to have occurred. If the suction superheat is greater than the preset superheat value ε, then liquid compression is determined not to have occurred. The preset superheat value ε is a pre-set suction superheat threshold value for liquid compression of the compressor. The preset superheat value ε can range from, for example, -1℃ to 0℃.

[0072] Specifically, the compressor's suction temperature Ti and suction pressure pi are detected, and the compressor's suction superheat ΔTi is calculated based on these values. If the compressor's suction superheat ΔTi is less than or equal to a preset superheat value ε, meaning the compressor's suction dryness is less than 1, the compressor is at risk of liquid slugging. If ΔTi is greater than ε, meaning the compressor's suction dryness is greater than 1, the air conditioner does not experience liquid compression. A compressor suction dryness of less than 1 indicates that the refrigerant at the compressor's suction port is in a gas-liquid two-phase state, containing liquid refrigerant, which will cause liquid compression when it enters the compressor. When the suction dryness is greater than 1, it indicates that the suction port is in a superheated state and does not contain liquid refrigerant, so liquid compression is not possible.

[0073] Given the saturated liquid enthalpy hin,l and saturated gaseous enthalpy hin,v of the refrigerant at the air conditioner evaporation pressure (or suction pressure) Pin, and the enthalpy of the refrigerant at the compressor suction port as hin = f(Pin,Tin), then the suction dryness fraction is x = (hin - hin,l) / (hin,v - hin,l).

[0074] Step S150: If it is determined that the compressor of the air conditioner is undergoing liquid compression, the opening of the throttling element of the air conditioner is reduced to increase the suction superheat of the compressor.

[0075] If it is determined that the compressor is experiencing liquid compression, the opening degree of the throttling element of the air conditioner is reduced to increase throttling and improve the compressor's suction superheat, thereby ensuring the compressor's reliability. The reduction in the opening degree of the throttling element of the air conditioner is denoted as the second opening degree Δk2.

[0076] Specifically, after each reduction of the preset opening degree (e.g., the throttling element is reduced by 2 steps each time), it is determined whether the compressor of the air conditioner is experiencing liquid compression based on the relationship between the suction superheat ΔTi of the compressor and the preset superheat value ε. If liquid compression still exists, the preset opening degree is reduced again until it is determined that the suction superheat ΔTi of the compressor is greater than the preset superheat value ε, that is, there is no liquid compression. The cumulative reduction in opening degree is recorded as the second opening degree Δk2.

[0077] Figure 3 This is a schematic diagram of another embodiment of the air conditioner control method provided by the present invention.

[0078] like Figure 3 As shown, according to another embodiment of the present invention, based on any of the above embodiments, the air conditioner control method further includes steps S160 and S170.

[0079] Step S160: If it is determined that the compressor of the air conditioner is undergoing liquid compression, after reducing the opening degree of the throttling element of the air conditioner, determine the relationship between the opening degree difference between the first opening degree and the second opening degree and the preset opening degree difference.

[0080] Step S170: If the difference between the first opening degree and the second opening degree is less than or equal to a preset opening degree difference, then adjust the compressor frequency according to the current suction pressure of the compressor and the temperature rise rate of the indoor heat exchanger tube.

[0081] Specifically, if the difference between the first opening degree Δk1 and the second opening degree Δk2 (Δk1-Δk2) is less than or equal to the preset opening degree difference A, that is, the difference in opening degree before and after the current throttling element control is not significant, and it cannot suppress the decrease in the inner pipe temperature, resulting in a decrease in the outlet air temperature, then based on the current compressor suction pressure pi and the temperature rise rate v of the indoor heat exchanger pipe temperature... T Adjust the compressor frequency.

[0082] In one specific implementation, the compressor frequency is increased by Δf, wherein...

[0083] Δf=c6pi+c7v T +c8

[0084] Where pi is the compressor's suction pressure; v T C1 represents the temperature rise rate of the indoor heat exchanger tubes; C6, C7, and C8 are fitting parameters that can be obtained experimentally.

[0085] When the compressor suction pressure pi is higher, the evaporation temperature is higher, the heat exchange temperature difference on the outdoor side of the heating unit is smaller, and the Δf is larger. This allows the compressor to improve heat exchange efficiency and suction superheat by increasing the frequency, even when the heat exchange is poor, thus meeting the requirements for compressor reliability and capacity improvement. Conversely, when the compressor suction pressure pi is lower, the Δf is smaller. This avoids a significant drop in air conditioner energy efficiency and allows the compressor to continue to improve suction superheat by reducing the opening of the throttling element.

[0086] Furthermore, after adjusting the compressor frequency, the first opening degree is reset so that, in the case that the compressor of the air conditioner is undergoing liquid compression, after reducing the opening degree of the throttling element of the air conditioner, the relationship between the opening degree difference between the first opening degree and the second opening degree and the preset opening degree difference is determined again.

[0087] Specifically, after controlling the compressor frequency to increase by Δf, it is necessary to return to determine whether there is a risk of liquid slugging in the compressor. Therefore, the throttling element opening increment (i.e., the first opening) Δk1' = Δk1 - Δk2 is reset, where Δk1' is the value of Δk1 after reassignment. Then, the compressor liquid compression determination program is executed again.

[0088] If the difference between the first opening degree Δk1 and the second opening degree Δk2 (Δk1-Δk2) is greater than the preset opening degree difference A, that is, the suction dryness can be directly controlled by the throttling device without first adjusting the compressor operating frequency F, then the judgment on whether the compressor has undergone liquid compression will continue.

[0089] Figure 4 This is a schematic diagram of another embodiment of the air conditioner control method provided by the present invention.

[0090] like Figure 4 As shown, according to another embodiment of the present invention, based on any of the above embodiments, the air conditioner control method further includes step S180. Figure 4 Only those based on Figure 3 (The illustrated method diagram of this embodiment is shown)

[0091] Step S180: If it is determined that the compressor has not undergone liquid compression, then the dwell time t of the compressor frequency dwell control is corrected according to the current throttling element opening degree and compressor frequency of the air conditioner.

[0092] In one specific embodiment, a correction duration is determined based on the current throttling element opening degree and compressor frequency of the air conditioner, and the dwell duration of the compressor frequency dwell control is corrected based on the determined correction duration; wherein, the corrected dwell duration t of the compressor frequency dwell control is equal to the current dwell duration t of the air conditioner's compressor frequency dwell control minus the correction duration Δt, and the correction duration Δt is determined based on the current throttling element opening degree and compressor frequency F of the air conditioner;

[0093] The correction duration Δt = c9Δk + c 10 k+c 11 F+c 12 ;

[0094] Where Δk equals the current throttling element opening k minus the initial throttling element opening k0 corresponding to the dwell point frequency of the compressor frequency dwell control, and F is the compressor frequency. When the compressor is in the frequency dwell control stage, the compressor frequency is the dwell point frequency of the compressor frequency control. c9, c 10 c 11 c 12 The fitting coefficients can be obtained by designing orthogonal validation experiments to finally fit the data.

[0095] When Δk is larger, that is, the opening of the throttling element is larger, the system circulation flow is higher, and the return of oil and fluid is better, then the correction time Δt is larger and the residence time is shorter; conversely, when Δk is smaller, the return of oil in the system is less, then the correction time Δt is smaller, and the residence time cannot be too short.

[0096] The correction amplitude Δt for the dwell time is also related to the compressor frequency F. The higher the compressor frequency F, the higher the compressor oil discharge rate, requiring a longer oil return time for the compressor to fully return oil, thus resulting in a smaller Δt. Conversely, the lower the compressor frequency F, the lower the compressor oil discharge rate, reducing the risk of oil shortage, thus resulting in a larger Δt, allowing the air conditioner to quickly enter the frequency ramp-up stage for heating.

[0097] Figure 5 This is a schematic diagram of another embodiment of the air conditioner control method provided by the present invention.

[0098] like Figure 5 As shown, according to one embodiment of the present invention, based on any of the above embodiments, the air conditioner control method further includes step S190.

[0099] Step S190: When the air conditioner meets the conditions for exiting compressor frequency pause control, control the air conditioner to resume normal heating operation.

[0100] The conditions for exiting compressor frequency dwell control include: the cumulative compressor running time s is greater than the sum of the cumulative compressor running time s1 when entering compressor frequency dwell control and the dwell time of compressor frequency dwell control.

[0101] Specifically, if the compressor's cumulative running time s is greater than the sum of the compressor's cumulative running time s1 when entering compressor frequency dwell control and the dwell time t of compressor frequency dwell control (i.e., s is greater than (s1+t), then the compressor has met the time condition to exit frequency dwell control and enter the frequency ramp-up stage. In this case, the compressor reliability control program exits and switches to normal heating operation. If the compressor's cumulative running time s is less than or equal to the sum of the compressor's cumulative running time s1 when entering compressor frequency dwell control and the dwell time t of compressor frequency dwell control (i.e., s is less than or equal to (s1+t), then the compressor is still in the frequency dwell control stage, and the above compressor reliability control program continues to be executed repeatedly.

[0102] To clearly illustrate the technical solution of the present invention, the execution flow of the air conditioner control method provided by the present invention will be described below with reference to a specific embodiment.

[0103] Figure 6 This is the air conditioning operation control logic of the present invention. For example... Figure 6 As shown, when the air conditioner is turned on for heating, it enters the anti-cold air control mode, the indoor fan is turned off or maintains a low speed, and the outdoor ambient temperature T is detected and recorded. w Indoor ambient temperature T n Calculate the temperature difference between indoor and outdoor environments (referred to as indoor-outdoor temperature difference): ΔT = T n -T w According to the outdoor ambient temperature T w The indoor-outdoor temperature difference ΔT determines the dwell point frequency F1 of the compressor frequency dwell control, based on the outdoor ambient temperature T. w Determine the dwell time t for compressor frequency dwell control, where the dwell point frequency F1 = c1T w+c2ΔT+c3, where c1, c2, and c3 are fitting coefficients obtained by fitting data through an orthogonal validation experiment. The duration of stay t is based on the outdoor ambient temperature T. w Pre-set the outdoor ambient temperature T w The lower the temperature and the larger the indoor-outdoor temperature difference ΔT, the worse the system's oil return condition. This results in a lower compressor dwell time frequency F1 and a longer dwell time t, leading to a lower compressor oil discharge rate and a longer oil return time, thus improving the system's oil return. The comparison between the compressor dwell time frequency F1 and the preset minimum compressor dwell time F... min The relationship when F1 < F min Then F1 takes F min To avoid a slow compressor oil return rate that could reduce air conditioner reliability. When the outdoor ambient temperature T w The higher the temperature and the smaller the indoor-outdoor temperature difference ΔT, the better the system's oil return condition. This results in a higher compressor dwell time frequency F1, a shorter dwell time t, greater heating output, and a faster indoor temperature rise rate. The comparison between F1 and the preset maximum compressor dwell time F... max The relationship when F1 > F max Then F1 takes F max This prevents the compressor from over-discharged oil, which could lead to oil shortage or oil depletion in the system, thus ensuring the reliability of the air conditioner's operation.

[0104] Obtain the compressor's frequency ramp-up rate v, and calculate the compressor's cumulative runtime s1 when it enters frequency dwell control. The calculation formula is as follows: s1=(F1-F start ) / v+s other

[0105] In the formula F start The initial starting frequency (Hz) of the compressor, s other This refers to the duration of the startup phase, which includes the compressor standby time (i.e., compressor standby startup time), compressor startup protection control time, and other times.

[0106] The temperature T inside the heat exchanger of the air conditioner is monitored and recorded in real time during the heating process. s (referred to as internal pipe temperature), first determine the air conditioner's internal pipe temperature T. s The relationship with the first preset temperature value T1, where: 1) if T s If the temperature is less than T1, meaning the internal pipe temperature of the air conditioner is low and the air outlet temperature is low, then the internal fan should remain off or running at low speed to prevent direct cold air from blowing out; 2) If T s If the temperature is greater than or equal to T1, meaning the temperature of the air conditioner's internal pipes is high enough to meet the conditions for exiting the anti-cold air control, then the anti-cold air control will be exited and the internal fan will switch to the set fan speed.

[0107] Considering that disabling the anti-cold air function might lead to insufficient heat output from the air conditioner, causing a rapid drop in air outlet temperature after increasing the fan speed, it is necessary to maximize the air conditioner's output capacity to improve comfort. When the air conditioner disables the anti-cold air function, the current cumulative compressor runtime 's' is detected and recorded. The relationship between the cumulative compressor runtime 's' and the preset runtime 's0' and the cumulative runtime 's1' at the dwell point is then determined.

[0108] If the compressor's cumulative running time s is less than or equal to the preset time s0, that is, the current room temperature is high, the load is low, the temperature rise rate is fast, and it is not easy to blow cold air, then maintain the current state of normal heating operation; before the compressor starts, the internal pipe temperature is similar to the room temperature. During the start-up phase, when the internal pipe temperature rise rate is faster than a certain value, that is, the time to reach the exit condition is less than or equal to s0, it indicates that the room temperature is high and it is not easy to blow cold air.

[0109] ii If the cumulative running time s of the compressor is greater than the preset time s0 and less than or equal to (s1+t), that is, when the air conditioner reaches the target internal pipe temperature condition for exiting the anti-cold air control, it just enters or is in the compressor frequency dwell control stage. At this time, exiting the anti-cold air control will cause the internal pipe temperature and the outlet air temperature to drop rapidly, so it enters the compressor reliability control to improve the heat output of the air conditioner.

[0110] iii. If s is greater than (s1+t), that is, the air conditioner is in the compressor frequency increase stage and the heating capacity continues to increase, then the current state of normal heating operation will be maintained.

[0111] Figure 7 This is the compressor reliability control logic according to the present invention. For example... Figure 7 As shown, after the air conditioner enters the compressor reliability control, the indoor heat exchanger tube temperature T is detected and recorded. s The rate of temperature rise v of the inner tube T First, determine the temperature T of the air conditioner's internal pipe. s The relationship with the second preset temperature value T2 (T2 is less than T1)

[0112] 1) If T s If the temperature is greater than T2, meaning that the internal pipe temperature drops slowly after the fan speed is restored and the outlet air temperature remains high, then the current operation will continue.

[0113] 2) If T s If the temperature is less than or equal to T2, meaning the internal pipe temperature and outlet air temperature drop rapidly after the fan speed is restored to normal, posing a risk of cold air blowing out, then the rate of temperature rise v of the air conditioner's internal pipe temperature should be calculated further. T Based on the calculated temperature rise rate v of the inner tube T Determine the opening increment Δk1 of the air conditioning flow control element.

[0114] When the temperature rise rate is negative (indicating a decrease in pipe temperature), the expansion valve opening increases by Δk1, resulting in increased system circulation flow, increased heat generation, and improved compressor oil return reliability. The greater the temperature drop rate, the larger Δk1 is, and vice versa.

[0115] However, it is necessary to avoid excessively low air conditioner exhaust temperature, reduced compressor suction superheat, and excessively low suction dryness, which could lead to compressor liquid compression and affect the reliable operation of the air conditioner. Therefore, the compressor suction temperature Ti and suction pressure pi are continuously monitored and recorded, the compressor suction superheat ΔTi is calculated, and the relationship between the suction superheat ΔTi and the preset superheat value ε is determined.

[0116] If ΔTi is less than or equal to ε, meaning the compressor suction dryness is less than 1, the compressor is at risk of liquid slugging. Therefore, the expansion valve opening Δk2 is reduced to increase throttling and improve suction superheat, ensuring compressor reliability. The relationship between (Δk1-Δk2) and the preset opening difference A is then assessed. If (Δk1-Δk2) is less than or equal to the preset opening difference A, meaning the difference in expansion valve opening before and after control is small, it cannot suppress the decrease in inner pipe temperature, resulting in a lower outlet air temperature. Therefore, based on the current compressor suction pressure pi and the inner pipe temperature rise rate v... T The compressor frequency is increased by Δf. When the compressor suction pressure pi is higher, the evaporation temperature is higher, and the heat exchange temperature difference on the outdoor heating side is smaller, resulting in a larger Δf. This allows for improved heat exchange efficiency and suction superheat even with poor heat exchange, meeting the requirements for compressor reliability and capacity enhancement. Conversely, when pi is lower, Δf is smaller to avoid a significant drop in air conditioner energy efficiency. The suction superheat is then increased by reducing the expansion valve opening. After increasing the compressor frequency by Δf, the expansion valve increment Δk1' = Δk1 - Δk2 is reset, where Δk1' is the reassigned value of Δk1. The compressor liquid slugging detection procedure is then executed again. If (Δk1 - Δk2) is greater than the preset opening difference A, meaning the suction dryness can be directly controlled via the expansion valve without prioritizing compressor frequency adjustment, the compressor liquid slugging detection procedure continues.

[0117] ii. If ΔTi is greater than the preset superheat value ε, i.e., the compressor suction dryness is greater than 1, the air conditioner does not have liquid compression. Continue to judge, detect and record the current expansion valve opening k. Based on the current compressor frequency F and expansion valve opening k, correct the dwell time t-Δt, where Δt=c9Δk+c 10 k+c 11 F+c 12 In the formula, Δk is the current valve opening k minus the initial valve opening corresponding to the frequency dwell control point. When Δk is larger, that is, the valve opening is larger, the system circulation flow is higher, and the oil and liquid return is better, then Δt is larger and the dwell time is shorter; conversely, when Δk is smaller, the system oil return is less, then Δt is smaller and the dwell time cannot be too short.

[0118] The magnitude of the residence time variation Δt is also related to the compressor residence frequency F. The higher the compressor frequency F, the higher the compressor oil discharge rate, requiring a longer oil return time for the compressor to fully return oil, thus resulting in a smaller Δt. Conversely, the lower the compressor frequency F, the lower the compressor oil discharge rate, reducing the risk of oil shortage, thus resulting in a larger Δt, allowing the air conditioner to quickly enter the frequency ramp-up stage for heating.

[0119] The compressor's cumulative runtime (in seconds) is continuously monitored and recorded during operation.

[0120] a. If s is greater than (s1+t), that is, the compressor reaches the time condition for exiting frequency dwell control and enters the frequency increase stage, then the compressor reliability control program will be exited and normal heating operation will be switched to normal operation.

[0121] b. If s is less than or equal to (s1+t), that is, the compressor is still in the frequency dwell control stage, then the above compressor reliability control program will continue to be executed repeatedly.

[0122] After adopting the above-mentioned air conditioning operation control method, the air conditioner can continue to maintain a high outlet air temperature and a large heat output after the anti-cold air control is turned off, thereby increasing the heating temperature rise rate, avoiding the air conditioner blowing cold air when heating, and avoiding problems such as compressor liquid slugging and oil shortage, thus ensuring reliable and comfortable operation of the air conditioner.

[0123] The present invention also provides a control device for an air conditioner.

[0124] Figure 8 This is a structural block diagram of an embodiment of the air conditioner control device provided by the present invention. Figure 8 As shown, the control device 100 includes: a first judgment unit 110, a second judgment unit 120, a control unit 130, and a third judgment unit 140.

[0125] The first judgment unit 110 is used to determine whether the air conditioner meets the conditions for exiting the anti-cold air control and whether the air conditioner is in the compressor frequency dwell control stage after the air conditioner is turned on for heating and enters the anti-cold air control.

[0126] The compressor frequency dwell control refers to maintaining the compressor at a set frequency for a set time during the frequency increase process after the compressor starts, and then continuing to increase the frequency; the set frequency is recorded as the dwell point frequency of the compressor frequency dwell control, and the set time is recorded as the dwell duration of the compressor frequency dwell control.

[0127] In one specific embodiment, the first determining unit 110 determines whether the air conditioner meets the conditions for exiting the anti-cold air control, including: determining the indoor heat exchanger tube temperature T of the air conditioner. s If the temperature is greater than or equal to the first preset temperature value T1, then the indoor heat exchanger tube temperature T is determined.s If the temperature is greater than or equal to the first preset temperature value T1, then the air conditioner is determined to meet the conditions for exiting the anti-cold air control.

[0128] Specifically, the temperature of the indoor heat exchanger tubes (referred to as the inner tube temperature) T is detected and recorded in real time. s Determine the temperature T of the indoor heat exchanger tubes in the air conditioner. s The relationship with the preset temperature value T1 is that the first preset temperature value T1 is the target internal pipe temperature of the indoor heat exchanger when the anti-cold air control is lifted. If T s If the temperature is less than T1, meaning the indoor heat exchanger pipe temperature is low and the air outlet temperature is low, then the indoor fan should remain off or running at low speed to prevent direct cold airflow; if T... s If the temperature is greater than or equal to T1, meaning the temperature of the indoor heat exchanger tube is high enough to meet the conditions for exiting the anti-cold air control, then the anti-cold air control will be exited and the indoor fan will switch to the set fan speed.

[0129] In one specific implementation, the first determination unit 110 determines whether the air conditioner is in the compressor frequency dwell control stage, including: if the cumulative running time s of the air conditioner's compressor is greater than the preset time s0, and less than or equal to the sum of the cumulative running time s1 of the compressor when entering the compressor frequency dwell control and the dwell time t of the compressor frequency dwell control, then it is determined that the air conditioner is in the compressor frequency dwell control stage.

[0130] When the air conditioner is turned on for heating, it enters anti-cold air control mode, the indoor fan is turned off or runs at the set low speed, and the outdoor ambient temperature T is detected and recorded. w Indoor ambient temperature T n Calculate the temperature difference between indoor and outdoor environments (referred to as indoor-outdoor temperature difference): ΔT = T n -T w According to the outdoor ambient temperature T w The temperature difference ΔT between indoor and outdoor ambient temperatures determines the dwell point frequency F1 of the compressor frequency dwell control, based on the outdoor ambient temperature T. w Determine the dwell time t for compressor frequency dwell control. This dwell time is the duration during which the compressor frequency is maintained at the frequency dwell point when performing compressor frequency dwell control; the dwell point frequency F1 = c1T. w +c2ΔT+c3, where c1, c2, and c3 are fitting coefficients, obtained by designing orthogonal verification experiments to fit the data.

[0131] Preferably, the control device 100 further includes: a first determining unit (not shown), used to determine the dwell time t of the compressor frequency dwell control. The dwell time t of the compressor frequency dwell control is based on the outdoor ambient temperature T. w To determine, determine the outdoor ambient temperature T. wThe temperature range is located within one or more preset temperature ranges, where each of the preset temperature ranges corresponds to a duration, i.e., based on the outdoor ambient temperature T. w The dwell time t of the air conditioner when performing compressor frequency dwell control is determined by the duration corresponding to the temperature range in one or more preset temperature ranges.

[0132] For example, ① when T w When A < T, the corresponding stay duration is t1; ② When A ≤ T w When ≤ B, the corresponding dwell time is t2; ③ When T w When A = -7℃ and B = 18℃, the corresponding dwell time is t3; for example, when A = -7℃ and B = 18℃, t1, t2, and t3 are 120s, 30s, and 0s, respectively.

[0133] When the outdoor ambient temperature T w The lower the temperature, the greater the indoor-outdoor temperature difference Δ T When the value is larger, the system oil return condition is poor, the compressor residence point frequency F1 is lower and the residence time t is longer, which makes the compressor oil discharge rate lower and the oil return time longer, thus improving the system oil return.

[0134] Preferably, the compressor dwell time frequency F1 is determined to be different from the preset minimum compressor dwell time frequency F. min The relationship when F1 < F min Then F1 takes F min To avoid a slow compressor oil return rate that could reduce air conditioner reliability. When the outdoor ambient temperature T w The higher the temperature and the smaller the indoor-outdoor temperature difference ΔT, the better the system's oil return condition. This results in a higher compressor dwell time frequency F1, a shorter dwell time t, greater heating output, and a faster indoor temperature rise rate. The comparison between F1 and the preset maximum compressor dwell time frequency F... max The relationship when F1 > F max Then F1 takes F max This prevents the compressor from over-discharged oil, which could lead to oil shortage or oil depletion in the system, thus ensuring the reliability of the air conditioner's operation.

[0135] Preferably, the control device 100 further includes: a second determining unit (not shown), used to determine the cumulative running time s1 of the compressor when entering the compressor frequency dwell control based on the compressor start-up initial frequency, the duration of the compressor start-up phase and the compressor frequency ramp-up rate.

[0136] In one specific implementation, the formula for calculating the cumulative compressor runtime s1 when entering compressor frequency dwell control is as follows:

[0137] s1=(F1-F start ) / v+s other

[0138] Where F1 is the dwell point frequency of the compressor frequency dwell control, F start The initial starting frequency (Hz) of the compressor, s other The duration of the compressor start-up phase can include, for example, compressor standby time (i.e., compressor standby start-up time), compressor start-up protection control time, compressor AC current or module current or overload protection frequency limiting time; v is the compressor frequency ramp-up rate, which is a fixed parameter value.

[0139] When the air conditioner meets the conditions for exiting the anti-cold air control, the current cumulative compressor running time s is detected, and the relationship between the cumulative compressor running time s and the preset time s0 and the cumulative running time s1 at the compressor frequency dwell point is determined.

[0140] If the cumulative running time s of the air conditioner compressor is less than or equal to the preset time s0, it indicates that the current room temperature is high, the load is low, and the temperature rise rate is fast, making it difficult to blow cold air. Therefore, the air conditioner will maintain its normal heating operation. Before the compressor starts, the indoor heat exchanger tube temperature is similar to the room temperature. During the start-up phase, if the indoor heat exchanger tube temperature rise rate is faster than a certain value, meaning the time to reach the exit condition is less than the preset time s0, it indicates that the room temperature is high and it is difficult to blow cold air. The preset time s0 can be measured experimentally or obtained based on the required indoor tube temperature rise rate.

[0141] If the cumulative running time s of the air conditioner compressor is greater than the preset time s0, and less than or equal to the sum of the cumulative running time s1 of the compressor and the dwell time t of the compressor frequency dwell control when entering the compressor frequency dwell control, that is, s is greater than s0 and less than or equal to (s1+t), that is, when the air conditioner reaches the target indoor pipe temperature condition for exiting the anti-cold air control, it just enters or is in the compressor frequency dwell control stage. At this time, exiting the anti-cold air control will cause the indoor heat exchanger pipe temperature and the outlet air temperature to drop rapidly, and then enter the compressor reliability control to improve the heat output of the air conditioner.

[0142] If the cumulative running time s of the air conditioner compressor is greater than the sum of the cumulative running time s1 of the compressor when entering the compressor frequency dwell control and the dwell time t of the compressor frequency dwell control, that is, s is greater than (s1+t), then the compressor has exited the frequency dwell control and the air conditioner is in the compressor frequency increase stage, and the heating capacity continues to increase, then the current state of normal heating operation is maintained.

[0143] The second judgment unit 120 is used to determine whether the indoor heat exchanger tube temperature of the air conditioner is less than or equal to a second preset temperature value when the first judgment unit 110 determines that the air conditioner meets the conditions for exiting the anti-cold air control and the air conditioner is in the compressor frequency dwell control stage.

[0144] Specifically, when it is determined that the air conditioner meets the conditions for exiting anti-cold air control, and the air conditioner is in the compressor frequency dwell control stage, it enters compressor reliability control. After entering compressor reliability control, the indoor heat exchanger tube temperature T is detected. s Determine the indoor heat exchanger tube temperature T s The relationship between T and the second preset temperature value T2. If T s If the temperature is greater than T2, meaning the internal pipe temperature drops slowly after resuming normal fan speed and the outlet air temperature remains high, then continue operating in the current state; if T... s If the temperature is less than or equal to T2, the internal pipe temperature and the outlet air temperature will drop rapidly after the fan speed is restored to normal, which may pose a risk of blowing cold air.

[0145] The control unit 130 is configured to increase the opening degree of the throttling element of the air conditioner according to the temperature rise rate of the indoor heat exchanger tubes if the second judgment unit 110 determines that the indoor heat exchanger tube temperature is less than or equal to a second preset temperature value.

[0146] The throttling element can specifically be a throttling element between the indoor and outdoor heat exchangers of an air conditioner. For example, by acquiring the temperature change value of the indoor heat exchanger tube temperature every n seconds, the temperature rise rate of the indoor heat exchanger tube temperature can be calculated.

[0147] In one specific embodiment, the control unit 130 increases the opening degree of the throttling element of the air conditioner according to the temperature rise rate of the indoor heat exchanger tube temperature, including: determining the interval in which the temperature rise rate of the indoor heat exchanger tube temperature falls within two or more preset temperature rise rate intervals; determining the opening degree increment of the throttling element of the air conditioner according to the opening degree increment corresponding to the interval in which the temperature rise rate of the indoor heat exchanger tube temperature falls within the two or more preset temperature rise rate intervals; and increasing the opening degree of the throttling element of the air conditioner according to the determined opening degree increment of the throttling element.

[0148] Wherein, each of the two or more preset temperature rise rate intervals corresponds to an opening increment; that is, the opening increment corresponding to the interval in which the temperature rise rate of the indoor heat exchanger tube falls within the two or more preset temperature rise rate intervals is determined as the opening increment of the throttling element of the air conditioner. The increased opening degree of the throttling element (i.e., the opening increment) is denoted as the first opening degree.

[0149] For example, the rate of temperature rise v of the indoor heat exchanger tubes. T When v T When the temperature is less than v1, meaning the inner tube temperature drops too quickly, increase the opening of the electronic expansion valve Δk1; when v1 ≤ v T When v ≤ v2, meaning the inner tube temperature drops slowly, increase the opening of the electronic expansion valve Δk2, where Δk1 > Δk2; when v TWhen the value is greater than v2, that is, the inner tube temperature drops very slowly or the tube temperature rises, the opening increment of the electronic expansion valve is 0.

[0150] In another specific embodiment, based on the indoor heat exchanger tube temperature v T According to a preset formula for calculating the opening increment, the opening increment Δk1 of the air conditioner's throttling element is determined; based on the determined opening increment Δk1, the opening of the air conditioner's throttling element is increased. The increased opening of the throttling element (i.e., the opening increment) is recorded as the first opening. The formula for calculating the opening increment is: Δk1 = c4v T +c5; where c4 and c5 are fitting coefficients, which can be obtained by designing orthogonal validation experiments to fit the data.

[0151] The control unit 100 is further configured to: when the first judgment unit 110 determines that the air conditioner meets the conditions for exiting the anti-cold air control, but the air conditioner is not in the compressor frequency dwell control stage, control the air conditioner to maintain the current state of heating operation; wherein, the situation where the air conditioner is not in the compressor frequency dwell control stage includes: the cumulative running time of the air conditioner's compressor is less than or equal to a preset time, and / or the cumulative running time of the air conditioner's compressor is greater than the sum of the cumulative running time of the compressor when entering the compressor frequency dwell control and the dwell time of the compressor frequency dwell control.

[0152] If the cumulative running time s of the air conditioner compressor is less than or equal to the preset time s0, it indicates that the current room temperature is high, the load is low, and the temperature rise rate is fast, making it difficult to blow cold air. Therefore, the air conditioner will maintain its normal heating operation. Before the compressor starts, the indoor heat exchanger tube temperature is similar to the room temperature. During the start-up phase, if the indoor heat exchanger tube temperature rise rate is faster than a certain value, meaning the time to reach the exit condition is less than the preset time s0, it indicates that the room temperature is high and it is difficult to blow cold air. The preset time s0 can be measured experimentally or obtained based on the required indoor tube temperature rise rate.

[0153] If the cumulative running time s of the air conditioner compressor is greater than the sum of the cumulative running time s1 of the compressor when entering the compressor frequency dwell control and the dwell time t of the compressor frequency dwell control, that is, s is greater than (s1+t), then the compressor has exited the frequency dwell control and the air conditioner is in the compressor frequency increase stage, and the heating capacity continues to increase, then the current state of normal heating operation is maintained.

[0154] The third judgment unit 140 is used to determine whether the compressor of the air conditioner is undergoing liquid compression based on the suction superheat of the air conditioner compressor after the control unit 130 increases the opening degree of the throttling element of the air conditioner.

[0155] The compressor's suction temperature Ti and suction pressure Pi are detected. The saturation temperature corresponding to the suction pressure Pi is looked up. The suction superheat ΔTi of the compressor is obtained by the difference between the suction temperature Ti and the saturation temperature corresponding to the suction pressure. Therefore, the compressor's suction superheat ΔTi is used to determine whether the air conditioner's compressor is undergoing liquid compression.

[0156] In one specific embodiment, the third determination unit 140 determines whether the air conditioner compressor is undergoing liquid compression based on the suction superheat of the air conditioner compressor, including: determining whether the air conditioner compressor is undergoing liquid compression based on the relationship between the suction superheat ΔTi of the compressor and a preset superheat value ε. Specifically, if the suction superheat is less than or equal to the preset superheat value ε, it is determined that the compressor is undergoing liquid compression; if the suction superheat is greater than the preset superheat value ε, it is determined that the compressor is not undergoing liquid compression.

[0157] The preset superheat value ε is a pre-set critical value for the intake superheat of the compressor during liquid compression. The preset superheat value ε can range from -1℃ to 0℃.

[0158] Specifically, the compressor's suction temperature Ti and suction pressure pi are detected, and the compressor's suction superheat ΔTi is calculated based on these values. If the compressor's suction superheat ΔTi is less than or equal to a preset superheat value ε, meaning the compressor's suction dryness is less than 1, the compressor is at risk of liquid slugging. If ΔTi is greater than ε, meaning the compressor's suction dryness is greater than 1, the air conditioner does not experience liquid compression. A compressor suction dryness of less than 1 indicates that the refrigerant at the compressor's suction port is in a gas-liquid two-phase state, containing liquid refrigerant, which will cause liquid compression when it enters the compressor. When the suction dryness is greater than 1, it indicates that the suction port is in a superheated state and does not contain liquid refrigerant, so liquid compression is not possible.

[0159] Given the saturated liquid enthalpy hin,l and saturated gaseous enthalpy hin,v of the refrigerant at the air conditioner evaporation pressure (or suction pressure) Pin, and the enthalpy of the refrigerant at the compressor suction port as hin = f(Pin,Tin), then the suction dryness fraction is x = (hin - hin,l) / (hin,v - hin,l).

[0160] The control unit 130 is further configured to: if the third judgment unit 140 determines that the compressor of the air conditioner is undergoing liquid compression, reduce the opening of the throttling element of the air conditioner to increase the suction superheat of the compressor.

[0161] If it is determined that the compressor is experiencing liquid compression, the opening degree of the throttling element of the air conditioner is reduced to increase throttling and improve the compressor's suction superheat, thereby ensuring the compressor's reliability. The reduction in the opening degree of the throttling element of the air conditioner is denoted as the second opening degree Δk2.

[0162] Specifically, after each reduction of the preset opening degree (e.g., the throttling element is reduced by 2 steps each time), it is determined whether the compressor of the air conditioner is experiencing liquid compression based on the relationship between the suction superheat ΔTi of the compressor and the preset superheat value ε. If liquid compression still exists, the preset opening degree is reduced again until it is determined that the suction superheat ΔTi of the compressor is greater than the preset superheat value ε, that is, there is no liquid compression. The cumulative reduction in opening degree is recorded as the second opening degree Δk2.

[0163] Figure 9 This is a structural block diagram of another embodiment of the air conditioner control device provided by the present invention. Figure 9 As shown, the control device 100 also includes a fourth judgment unit 160 and an adjustment unit 170.

[0164] The fourth judgment unit 160 is used to determine the relationship between the difference between the first opening degree and the second opening degree and the preset opening degree difference if the third judgment unit 140 determines that the compressor of the air conditioner is undergoing liquid compression and reduces the opening degree of the throttling element of the air conditioner.

[0165] The adjustment unit 170 is used to adjust the compressor frequency according to the current suction pressure of the compressor and the temperature rise rate of the indoor heat exchanger tube if the fourth judgment unit 160 determines that the difference between the first opening degree and the second opening degree is less than or equal to a preset opening degree difference.

[0166] Specifically, if the difference between the first opening degree Δk1 and the second opening degree Δk2 (Δk1-Δk2) is less than or equal to the preset opening degree difference A, that is, the difference in opening degree before and after the current throttling element control is not significant, and it cannot suppress the decrease in the inner pipe temperature, resulting in a decrease in the outlet air temperature, then based on the current compressor suction pressure pi and the temperature rise rate v of the indoor heat exchanger pipe temperature... T Adjust the compressor frequency.

[0167] In one specific implementation, the compressor frequency is increased by Δf, wherein...

[0168] Δf=c6pi+c7v T +c8

[0169] Where pi is the compressor's suction pressure; v T C1 represents the temperature rise rate of the indoor heat exchanger tubes; C6, C7, and C8 are fitting parameters that can be obtained experimentally.

[0170] When the compressor suction pressure pi is higher, the evaporation temperature is higher, the heat exchange temperature difference on the outdoor side of the heating unit is smaller, and the Δf is larger. This allows the compressor to improve heat exchange efficiency and suction superheat by increasing the frequency, even when the heat exchange is poor, thus meeting the requirements for compressor reliability and capacity improvement. Conversely, when the compressor suction pressure pi is lower, the Δf is smaller. This avoids a significant drop in air conditioner energy efficiency, and the suction superheat is further increased by reducing the opening of the expansion valve.

[0171] Furthermore, the control device 100 further includes: a reset unit (not shown), used to reset the first opening degree after the adjustment unit adjusts the compressor frequency, so that when the third judgment unit determines that the compressor of the air conditioner is undergoing liquid compression, after the control unit reduces the opening degree of the throttling element of the air conditioner, the fourth judgment unit again judges the relationship between the opening degree difference between the first opening degree and the second opening degree and the preset opening degree difference.

[0172] After controlling the compressor frequency to increase by Δf, it is necessary to return to determine whether there is a risk of liquid slugging in the compressor. Therefore, the throttling element opening increment (i.e. the first opening) Δk1' = Δk1 - Δk2 is reset, where Δk1' is the value of Δk1 after reassignment. Then, the compressor liquid compression determination program is executed again.

[0173] If the difference between the first opening degree Δk1 and the second opening degree Δk2 (Δk1-Δk2) is greater than the preset opening degree difference A, that is, the suction dryness can be directly controlled by the throttling device without first adjusting the compressor operating frequency F, then the judgment on whether the compressor has undergone liquid compression will continue.

[0174] Figure 10 This is a structural block diagram of another embodiment of the air conditioner control device provided by the present invention. Figure 10 As shown, based on any of the above embodiments, the control device 100 further includes a correction unit 180.

[0175] The correction unit 180 is used to correct the dwell time of the compressor frequency dwell control based on the current throttling element opening degree of the air conditioner and the compressor frequency dwell point frequency if the third judgment unit 140 determines that the compressor has not undergone liquid compression.

[0176] In one specific implementation, a correction duration is determined based on the current throttling element opening and compressor frequency of the air conditioner, and the dwell duration of the compressor frequency dwell control is corrected based on the determined correction duration; wherein, the corrected dwell duration is equal to the dwell duration of the current compressor frequency dwell control of the air conditioner minus the correction duration, and the correction duration Δt is determined based on the current throttling element opening and compressor frequency F of the air conditioner;

[0177] The correction duration Δt = c9Δk + c 10 k+c 11 F+c 12 ;

[0178] Where Δk equals the current throttling element opening k minus the initial throttling element opening k0 corresponding to the dwell point frequency of the compressor frequency dwell control, and F is the compressor frequency. When the compressor is in the frequency dwell control stage, the compressor frequency is the dwell point frequency of the compressor frequency control. c9, c 10 c 11 c 12 The fitting coefficients can be obtained by designing orthogonal validation experiments to finally fit the data.

[0179] When Δk is larger, that is, the opening of the throttling element is larger, the system circulation flow is higher, and the return of oil and fluid is better, then the correction time Δt is larger and the residence time is shorter; conversely, when Δk is smaller, the return of oil in the system is less, then the correction time Δt is smaller, and the residence time cannot be too short.

[0180] The correction amplitude Δt for the dwell time is also related to the compressor frequency F. The higher the compressor frequency F, the higher the compressor oil discharge rate, requiring a longer oil return time for the compressor to fully return oil, thus resulting in a smaller Δt. Conversely, the lower the compressor frequency F, the lower the compressor oil discharge rate, reducing the risk of oil shortage, thus resulting in a larger Δt, allowing the air conditioner to quickly enter the frequency ramp-up stage for heating.

[0181] According to another embodiment of the present invention, based on the above embodiment, the control unit 130 is further configured to: control the air conditioner to resume normal heating operation when the air conditioner meets the conditions for exiting compressor frequency dwell control.

[0182] The conditions for exiting compressor frequency dwell control include: the cumulative compressor running time s is greater than the sum of the cumulative compressor running time s1 when entering compressor frequency dwell control and the dwell time of compressor frequency dwell control.

[0183] Specifically, if the compressor's cumulative running time s is greater than the sum of the compressor's cumulative running time s1 when entering compressor frequency dwell control and the dwell time t of compressor frequency dwell control (i.e., s is greater than (s1+t), then the compressor has met the time condition to exit frequency dwell control and enter the frequency ramp-up stage. In this case, the compressor reliability control program exits and switches to normal heating operation. If the compressor's cumulative running time s is less than or equal to the sum of the compressor's cumulative running time s1 when entering compressor frequency dwell control and the dwell time t of compressor frequency dwell control (i.e., s is less than or equal to (s1+t), then the compressor is still in the frequency dwell control stage, and the above compressor reliability control program continues to be executed repeatedly.

[0184] The present invention also provides a storage medium corresponding to the control method of the air conditioner, wherein a computer program is stored thereon, and the program, when executed by a processor, implements the steps of any of the aforementioned methods.

[0185] The present invention also provides an air conditioner corresponding to the control method of the air conditioner, comprising a processor, a memory, and a computer program stored in the memory that can run on the processor, wherein the processor executes the program to implement the steps of any of the aforementioned methods.

[0186] The present invention also provides an air conditioner corresponding to the control device of the air conditioner, including the control device of any of the aforementioned air conditioners.

[0187] Accordingly, the solution provided by this invention, when the anti-cold air operation is exited during heating and the system is in the frequency dwell control stage, adjusts the opening degree of the throttling element based on the changes in the inner pipe temperature and the rate of change of the inner pipe temperature to increase the air conditioning capacity output and improve system oil return. This can increase the air outlet temperature of the air conditioner and shorten the dwell time of constant frequency operation. At the same time, it identifies and controls liquid compression through the compressor suction dryness, and controls the frequency and the opening degree of the throttling element in conjunction to increase the heat output of the air conditioner while avoiding liquid compression of the compressor, thus improving both user heating comfort and compressor operation reliability. While meeting the requirement of rapid hot air blowing during heating, this solution addresses the problem of reduced air conditioning system reliability under high heat output conditions in existing air conditioners, achieving comfortable and reliable air conditioning operation and improving user experience.

[0188] According to the technical solution of the present invention, by using multiple parameters to comprehensively control the system reliability, the problem of poor heating comfort caused by the single reliability control method of the current compressor can be solved. While ensuring the air conditioner's high capacity output and rapid heating operation, reliability problems such as compressor oil shortage, oil-air shortage, or liquid compression are avoided, thereby maximizing user heating comfort and compressor lifespan.

[0189] The functions described herein can be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions can be stored as one or more instructions or codes on or transmitted via a computer-readable medium. Other examples and embodiments are within the scope and spirit of this invention and the appended claims. For example, due to the nature of software, the functions described above can be implemented using software executed by a processor, hardware, firmware, hardwired, or any combination thereof. Furthermore, the functional units can be integrated into a single processing unit, or each unit can exist physically separately, or two or more units can be integrated into a single unit.

[0190] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0191] The units described as separate components may or may not be physically separate. Similarly, the components of the control device may or may not be physical units; they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0192] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to related technologies, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0193] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A control method of an air conditioner, characterized by, The method comprises the following steps: After the air conditioner is started and enters the cold-wind prevention control, it is determined whether the air conditioner meets the condition for exiting the cold-wind prevention control and whether the air conditioner is in the compressor frequency stay control stage, comprising: if the accumulated running time of the compressor of the air conditioner is greater than a preset time length and less than or equal to the sum of the accumulated running time of the compressor when entering the compressor frequency stay control and the stay time length of the compressor frequency stay control, it is determined that the air conditioner is in the compressor frequency stay control stage; When it is determined that the air conditioner meets the condition for exiting the cold-wind prevention control and the air conditioner is in the compressor frequency stay control stage, it is determined whether the indoor heat exchanger pipe temperature of the air conditioner is less than or equal to a second preset temperature value; If it is determined that the indoor heat exchanger pipe temperature is less than or equal to the second preset temperature value, the opening degree of the throttling element of the air conditioner is increased according to the temperature rise rate of the indoor heat exchanger pipe temperature, wherein the increased opening degree of the throttling element is recorded as a first opening degree, and the increased opening degree is equal to the opening degree after the increase minus the opening degree before the increase; After the opening degree of the throttling element of the air conditioner is increased, it is determined whether the compressor of the air conditioner is in liquid compression according to the suction superheat degree of the compressor of the air conditioner, comprising: it is determined whether the compressor of the air conditioner is in liquid compression according to the size relationship between the suction superheat degree of the compressor and a preset superheat degree value; wherein if the suction superheat degree is less than or equal to the preset superheat degree value, it is determined that the compressor is in liquid compression, and if the suction superheat degree is greater than the preset superheat degree value, it is determined that the compressor is not in liquid compression; If it is determined that the compressor of the air conditioner is in liquid compression, the opening degree of the throttling element of the air conditioner is reduced to increase the suction superheat degree of the compressor, wherein the reduced opening degree of the throttling element is recorded as a second opening degree, and the reduced opening degree is equal to the opening degree before the reduction minus the opening degree after the reduction.

2. The method of claim 1, wherein It is determined whether the air conditioner meets the condition for exiting the cold-wind prevention control, comprising: It is determined whether the indoor heat exchanger pipe temperature of the air conditioner is greater than or equal to a first preset temperature value, and if it is determined that the indoor heat exchanger pipe temperature is greater than or equal to the first preset temperature value, it is determined that the air conditioner meets the condition for exiting the cold-wind prevention control; And / or The opening degree of the throttling element of the air conditioner is increased according to the temperature rise rate of the indoor heat exchanger pipe temperature, comprising: It is determined that the temperature rise rate of the indoor heat exchanger pipe temperature is in a range in the preset two or more temperature rise rate ranges, wherein each range in the preset two or more temperature rise rate ranges corresponds to an opening degree increment; The opening degree increment of the throttling element of the air conditioner is determined according to the opening degree increment corresponding to the range in the preset two or more temperature rise rate ranges in which the temperature rise rate of the indoor heat exchanger pipe temperature is located; The opening degree of the throttling element of the air conditioner is increased according to the determination of the opening degree increment of the throttling element of the air conditioner.

3. The method according to claim 1 or 2, characterized in that, Further comprising: When it is determined that the air conditioner meets the condition for exiting the cold-wind prevention control, but the air conditioner is not in the compressor frequency stay control stage, the air conditioner is controlled to maintain the current state of heating operation. The condition that the air conditioner is not in the compressor frequency stay control stage includes: The accumulated running time length of the compressor of the air conditioner is less than or equal to a preset time length, and / or the accumulated running time length of the compressor of the air conditioner is greater than the sum of the accumulated running time length of the compressor when entering the compressor frequency stay control and the stay time length of the compressor frequency stay control; And / or, When the air conditioner meets the condition of exiting the compressor frequency stay control, the air conditioner is controlled to resume normal heating operation; The condition of exiting the compressor frequency stay control includes that the accumulated running time length of the compressor is greater than the sum of the accumulated running time length of the compressor when entering the compressor frequency stay control and the stay time length of the compressor frequency stay control; And / or, If it is judged that the compressor of the air conditioner occurs liquid compression, after reducing the opening degree of the throttling element of the air conditioner, the size relationship between the opening degree difference value of the first opening degree and the second opening degree and a preset opening degree difference value is judged; If the opening degree difference value of the first opening degree and the second opening degree is less than or equal to the preset opening degree difference value, the current suction pressure of the compressor and the temperature rise rate of the indoor heat exchanger pipe temperature are used to adjust the compressor frequency; And / or, If it is judged that the compressor of the air conditioner does not occur liquid compression, the current opening degree of the throttling element and the compressor frequency of the air conditioner are used to correct the stay time length of the compressor frequency stay control.

4. The method of claim 3, wherein The stay time length of the compressor frequency stay control is determined according to the outdoor environment temperature, including: Determining the temperature interval in which the outdoor environment temperature is located among the preset two or more temperature intervals; wherein each temperature interval in the preset two or more temperature intervals corresponds to a time length; According to the time length corresponding to the temperature interval in which the outdoor environment temperature is located among the preset two or more temperature intervals, the stay time length of the compressor frequency stay control currently performed by the air conditioner is determined; And / or, The accumulated running time length of the compressor when entering the compressor frequency stay control is determined according to the initial frequency of the compressor start, the time length of the compressor start stage and the frequency increasing rate of the compressor; The calculation formula of the accumulated running time length s1 of the compressor when entering the compressor frequency stay control is as follows: s1= (F1-F start ) / v + s other wherein F1 is the hold point frequency of the compressor frequency hold control, F start is the compressor start initial frequency, s other is the compressor start phase duration, v is the compressor ramp rate; And / or, further including: After adjusting the compressor frequency, the first opening degree is reset, so that in the case that it is judged that the compressor of the air conditioner occurs liquid compression, the size relationship between the opening degree difference value of the first opening degree and the second opening degree and a preset opening degree difference value is judged again after reducing the opening degree of the throttling element of the air conditioner; And / or, According to the current throttling element opening degree and the compressor frequency of the air conditioner, the stay time length of the compressor frequency stay control is corrected, including: The correction time length is determined according to the current throttling element opening degree and the compressor frequency of the air conditioner, and the stay time length of the compressor frequency stay control is corrected according to the determined correction time length; The corrected stay time length is equal to the stay time length of the compressor frequency stay control of the air conditioner minus the correction time length.

5. A control device of an air conditioner, characterized by comprising: Including: The first judging unit is configured to judge whether the air conditioner meets the condition for exiting the cold-wind prevention control and whether the air conditioner is in the compressor frequency staying control stage after the air conditioner is started and enters the cold-wind prevention control, including: if the accumulated running time of the compressor of the air conditioner is greater than a preset time length and less than or equal to the sum of the accumulated running time of the compressor when entering the compressor frequency staying control and the staying time length of the compressor frequency staying control, it is determined that the air conditioner is in the compressor frequency staying control stage; The second judging unit is configured to judge whether the indoor heat exchanger pipe temperature of the air conditioner is less than or equal to a second preset temperature value when the first judging unit judges that the air conditioner meets the condition for exiting the cold-wind prevention control and the air conditioner is in the compressor frequency staying control stage. The control unit is configured to increase the opening degree of the throttling element of the air conditioner according to the temperature rise rate of the indoor heat exchanger pipe temperature if the second judging unit judges that the indoor heat exchanger pipe temperature is less than or equal to the second preset temperature value, wherein the increased opening degree of the throttling element is recorded as a first opening degree, and the increased opening degree is equal to the opening degree after the increase minus the opening degree before the increase. The third judging unit is configured to judge whether the compressor of the air conditioner is in liquid compression according to the suction superheat degree of the compressor after the control unit increases the opening degree of the throttling element of the air conditioner, including: judging whether the compressor of the air conditioner is in liquid compression according to the size relationship between the suction superheat degree of the compressor and a preset superheat degree value; wherein if the suction superheat degree is less than or equal to the preset superheat degree value, it is determined that the compressor is in liquid compression, and if the suction superheat degree is greater than the preset superheat degree value, it is determined that the compressor is not in liquid compression. The control unit is further configured to decrease the opening degree of the throttling element of the air conditioner to increase the suction superheat degree of the compressor if the third judging unit judges that the compressor of the air conditioner is in liquid compression, wherein the decreased opening degree of the throttling element is recorded as a second opening degree, and the decreased opening degree is equal to the opening degree before the decrease minus the opening degree after the decrease.

6. The control device according to claim 5, wherein The first judging unit judges whether the air conditioner meets the condition for exiting the cold-wind prevention control, including: judging whether the indoor heat exchanger pipe temperature of the air conditioner is greater than or equal to a first preset temperature value, and if it is judged that the indoor heat exchanger pipe temperature is greater than or equal to the first preset temperature value, it is determined that the air conditioner meets the condition for exiting the cold-wind prevention control; and / or The control unit increases the opening degree of the throttling element of the air conditioner according to the temperature rise rate of the indoor heat exchanger pipe temperature, including: determining the interval in which the temperature rise rate of the indoor heat exchanger pipe temperature is located among the preset two or more temperature rise rate intervals, wherein each interval in the preset two or more temperature rise rate intervals corresponds to an opening degree increment; determining the opening degree increment of the throttling element of the air conditioner according to the opening degree increment corresponding to the interval in which the temperature rise rate of the indoor heat exchanger pipe temperature is located among the preset two or more temperature rise rate intervals. According to a determination of an opening increment of a throttling element of the air conditioner, the opening of the throttling element of the air conditioner is increased.

7. The control device according to claim 5 or 6, characterized in that, The control unit is further configured to control the air conditioner to maintain current state heating operation when it is determined that the air conditioner meets the condition for exiting the anti-cold-wind control but the air conditioner is not in the compressor frequency staying control phase. The condition that the air conditioner is not in the compressor frequency staying control phase includes: The accumulated operation time length of the compressor of the air conditioner is less than or equal to a preset time length, and / or the accumulated operation time length of the compressor of the air conditioner is greater than the sum of the accumulated operation time length of the compressor when entering the compressor frequency staying control and the staying time length of the compressor frequency staying control. And / or, The control unit is further configured to control the air conditioner to restore normal heating operation when the air conditioner meets the condition for exiting the compressor frequency staying control. The condition for exiting the compressor frequency staying control includes that the accumulated operation time length of the compressor is greater than the sum of the accumulated operation time length of the compressor when entering the compressor frequency staying control and the staying time length of the compressor frequency staying control. And / or, The control device further includes: A fourth determination unit configured to determine the size relationship between the opening difference value of the first opening and the second opening and a preset opening difference value if the third determination unit determines that the compressor of the air conditioner is in liquid compression after the opening of the throttling element of the air conditioner is reduced. An adjustment unit configured to adjust the compressor frequency according to the current suction pressure of the compressor and the temperature rise rate of the indoor heat exchanger tube temperature if the fourth determination unit determines that the opening difference value of the first opening and the second opening is less than or equal to the preset opening difference value. And / or, Further including: A correction unit configured to correct the staying time length of the compressor frequency staying control according to the current opening of the throttling element and the compressor frequency of the air conditioner if the third determination unit determines that the compressor of the air conditioner is not in liquid compression.

8. The control device according to claim 7, characterized in that, The control device further includes a first determination unit configured to determine the staying time length of the compressor frequency staying control, wherein the staying time length of the compressor frequency staying control is determined according to the outdoor environment temperature, including: Determining the temperature interval in which the outdoor environment temperature is located among the preset two or more temperature intervals, wherein each temperature interval in the preset two or more temperature intervals corresponds to a time length; Determining the staying time length of the compressor frequency staying control currently performed by the air conditioner according to the time length corresponding to the temperature interval in which the outdoor environment temperature is located among the preset two or more temperature intervals; And / or, The control device further includes a second determination unit configured to determine the accumulated operation time length of the compressor when entering the compressor frequency staying control according to the initial frequency of the compressor at startup, the time length of the compressor at startup phase, and the frequency increasing rate of the compressor. The calculation formula of the accumulated operation time length s1 of the compressor when entering the compressor frequency staying control is as follows: s1 = (F1 - F start ) / v + s other wherein, F1 is the dwell point frequency of the compressor frequency dwell control, F star t is the initial frequency of the compressor start-up, s other is the duration of the compressor start-up phase, v is the frequency ramp rate of the compressor; And / or, The control device further comprises a resetting unit configured to reset the first opening degree after the adjusting unit adjusts the compressor frequency, so that, when the third judging unit judges that the compressor of the air conditioner is in the liquid compression state, the fourth judging unit judges the size relationship between the opening degree difference between the first opening degree and the second opening degree and the preset opening degree difference again after the control unit reduces the opening degree of the throttling element of the air conditioner. And / or, The correcting unit corrects the staying time length of the compressor frequency staying control according to the current throttling element opening degree and the compressor frequency of the air conditioner, and the correcting comprises: determining a correction time length according to the current throttling element opening degree and the compressor frequency of the air conditioner, and correcting the staying time length of the compressor frequency staying control according to the determined correction time length; wherein the corrected staying time length is equal to the staying time length of the compressor frequency staying control of the air conditioner minus the correction time length.

9. A storage medium, characterized by A computer program is stored on the computer readable medium, and the program is executed by the processor to implement the steps of the method of any one of claims 1-4.

10. An air conditioner characterized by comprising: The control device comprises a processor, a memory, and a computer program stored on the memory and executable on the processor, and the processor implements the steps of the method of any one of claims 1-4 when executing the program, or comprises the control device of the air conditioner of any one of claims 5-8.

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