CN113446706B - Air conditioner control method and air conditioner - Google Patents

Abstract

The air conditioner control method includes: starting the air conditioner, and in a first set period: sampling the first high pressure detection value of the exhaust end of the compressor; sampling the first low pressure detection value of the return air end of the compressor; calculating the first pressure ratio; In the second set period that is continuous with the first set period: sampling the second high pressure detection value of the exhaust end of the compressor; sampling the second low pressure detection value of the return air end of the compressor; calculating the second pressure ratio; The first pressure ratio and the second pressure ratio determine a compressor frequency change speed, and the compressor operation is controlled according to the compressor frequency change speed. At the same time, an air conditioner is also disclosed. The present invention can accurately determine whether the current compressor working state is adapted to the system pressure ratio through two cycles of continuous monitoring, and determine the compressor frequency change speed in the next cycle according to the adaptation state, ensuring that even if there is an unopened valve The air conditioning system can also remain stable and safe.

Description

Air conditioner control method and air conditioner

technical field

The invention belongs to the technical field of air conditioning equipment, and in particular relates to a control method for an air conditioner and an air conditioner using the control method.

Background technique

A cut-off valve is provided in the split type air conditioner, and the cut-off valve is set on the pipeline connecting the indoor unit and the outdoor unit to close or open the refrigerant circuit. It also acts as a switch when vacuuming or charging refrigerant.

When the split air conditioner is powered on and used, especially when it is installed and used for the first time, the shut-off valve should be in the open state to ensure the normal flow of refrigerant between the indoor unit and the outdoor unit. However, due to the negligence of the installer, the failure of the shut-off valve itself, or the communication failure, the air conditioner may be turned on directly without the valve being fully opened. In this state, the operation mode of the air conditioner is abnormal, especially after a period of operation, the pressure of the entire refrigeration cycle will increase and exceed the safety threshold. Some models with shutdown protection may start frequently, and in extreme cases, the refrigerant line may rupture from the pipe wall. cause refrigerant leakage. The leaked refrigerant will explode when it encounters electric sparks, causing serious safety accidents.

The above information disclosed in this Background is only for enhancement of understanding of the background of the application and therefore it may contain that it does not form the prior art that is already known to a person of ordinary skill in the art.

SUMMARY OF THE INVENTION

The present invention designs and provides a control method for an air conditioner in view of the fact that the air conditioner may be directly turned on without fully opening the valve due to the negligence of the installer, the failure of the shut-off valve itself or the communication failure in the prior art.

In order to realize the above-mentioned purpose of the invention, the present invention adopts the following technical scheme to realize:

A method for controlling an air conditioner, comprising the steps of: starting the air conditioner, and in a first set period: sampling a first high pressure detection value of a compressor discharge end; sampling a first low pressure detection value of a compressor return air end; calculating a first pressure ratio, the first pressure ratio is the ratio of the first high pressure detection value and the first low pressure detection value; in the second set period that is continuous with the first set period: sampling compressor discharge The second high pressure detection value of the gas end; sampling the second low pressure detection value of the return air end of the compressor; calculating the second pressure ratio, the second pressure ratio is the ratio of the second high pressure detection value and the second low pressure detection value ; Determine the compressor frequency change speed according to the first pressure ratio and the second pressure ratio, and control the compressor operation according to the compressor frequency change speed.

Further, it also includes the following steps: after obtaining the first pressure ratio, calling the corresponding set compressor frequency change speed according to the first pressure ratio; after obtaining the second pressure ratio, according to the first pressure ratio The two pressure ratios calibrate the set compressor frequency change speed to obtain the calibrated compressor frequency conversion speed; control the compressor to run according to the calibrated compressor frequency conversion speed.

Further, calling the corresponding set compressor frequency change speed according to the first pressure ratio includes the following steps: if the first pressure ratio belongs to the first set pressure ratio interval, set the compressor frequency change speed to be the first A frequency-up speed; if the first pressure ratio belongs to the second set pressure ratio interval, set the compressor frequency change speed as the second frequency-up speed; if the first pressure ratio belongs to the third set pressure ratio interval, the compressor frequency change speed is set as the third frequency increase speed; wherein, the first frequency increase speed is greater than the second frequency increase speed, and the second frequency increase speed is greater than or equal to the third frequency increase speed frequency and speed; the first set pressure ratio interval, the second set pressure ratio interval and the third set pressure ratio interval are continuous and the upper limit threshold value increases sequentially.

Further, calibrating the set compressor frequency change speed according to the second pressure ratio, and obtaining the calibrated compressor frequency conversion speed includes the following steps: if the second pressure ratio belongs to the first set pressure ratio range, keep the set compressor frequency change speed. The set compressor frequency change speed is unchanged, the calibrated compressor frequency conversion speed is equal to the set compressor frequency change speed, and the compressor is controlled to increase frequency operation; if the second pressure ratio belongs to the second set pressure ratio If the second pressure ratio belongs to the third set pressure ratio range, the set compressor frequency change speed is calibrated to the set frequency reduction speed , control the compressor to run at a reduced frequency.

Further, calibrating the set compressor frequency change speed to the set frequency reduction speed includes the following steps: if within the first set period, the first pressure ratio belongs to the first set pressure ratio range, then Calibrate the set compressor frequency change speed to the first set frequency reduction speed; if within the first set period, the first pressure ratio belongs to the second set pressure ratio range, set the set The compressor frequency change speed is calibrated to the second set frequency reduction speed; if within the first set period, the first pressure ratio belongs to the third set pressure ratio interval, the set compressor frequency change speed is set to Calibrated to a third set frequency reduction speed; wherein, the absolute value of the first set frequency reduction speed is greater than the absolute value of the second set frequency reduction speed, and the absolute value of the second set frequency reduction speed greater than or equal to the absolute value of the third set frequency reduction speed.

Further, it also includes the following steps: after calculating the first pressure ratio, first determine whether the first pressure ratio belongs to the protection pressure ratio interval, and if the first pressure ratio belongs to the protection pressure ratio interval, control the The compressor shuts down and stops calibrating the set compressor frequency change speed according to the second pressure ratio; wherein the protection pressure ratio interval is continuous with the third set pressure ratio interval, and the protection pressure ratio interval is The lower threshold is greater than the upper threshold of the third set pressure ratio.

Further, it also includes the following steps: if the first pressure ratio belongs to the protection pressure ratio interval, further determining whether the second pressure ratio belongs to the first set pressure ratio interval; if the second pressure ratio belongs to the first set pressure ratio interval Set the pressure ratio range, control the compressor to stop while keeping the pressure relief valve closed; wherein, the first end of the pressure relief valve is connected to the first refrigerant passage, and the second end of the pressure relief valve is connected to the second refrigerant passage. a refrigerant passage; the first refrigerant passage is arranged between the indoor heat exchanger and the outdoor heat exchanger, the second refrigerant passage is arranged between the outdoor heat exchanger and the indoor heat exchanger, the first refrigerant passage is A shut-off valve is provided on the refrigerant passage and/or the second refrigerant passage.

Further, it also includes the following steps: after calculating the second pressure ratio, first determine whether the second pressure ratio belongs to the protection pressure ratio interval, and if the second pressure ratio belongs to the protection pressure ratio interval, control the Compressor stops.

Further, it also includes the following steps: if the first pressure ratio and the second pressure ratio are both in the protection pressure ratio range, controlling the compressor to stop and controlling the pressure relief valve to open; wherein, the pressure relief valve The first end is connected to the first refrigerant passage, the second end of the pressure relief valve is connected to the second refrigerant passage, and the first refrigerant passage is arranged between the indoor heat exchanger and the outdoor heat exchanger. Two refrigerant passages are arranged between the outdoor heat exchanger and the indoor heat exchanger, and a stop valve is arranged on the first refrigerant passage and/or the second refrigerant passage.

Another aspect of the present invention provides an air conditioner, which adopts the following control method: comprising the following steps: starting the air conditioner, and in a first set period: sampling the first high-pressure detection value of the exhaust end of the compressor; sampling the return of the compressor The first low pressure detection value of the gas end; calculate the first pressure ratio, the first pressure ratio is the ratio of the first high pressure detection value and the first low pressure detection value; In the second set period: sampling the second high pressure detection value of the exhaust end of the compressor; sampling the second low pressure detection value of the return air end of the compressor; calculating the second pressure ratio, the second pressure ratio is the second high pressure detection value The ratio of the value to the second low pressure detection value; the compressor frequency change speed is determined according to the first pressure ratio and the second pressure ratio, and the compressor operation is controlled according to the compressor frequency change speed.

Compared with the prior art, the advantages and positive effects of the present invention are:

The present invention can accurately determine whether the current compressor operating state is adapted to the system pressure ratio through two cycles of continuous monitoring, and determine the compressor frequency change speed in the next cycle according to the adaptation state. Under the condition that the system pressure ratio is suitable, adjust the compressor frequency change speed appropriately with adjusting the air-conditioning room load as the primary goal; under the condition that the system pressure ratio is not suitable, actively intervene to change the compressor frequency change speed to form a dynamic The adjustment scheme ensures that the complex coupled air conditioning system composed of multiple components, multiple heat exchange processes and affected by various external conditions remains stable and safe even if the valve is not opened.

Other features and advantages of the present invention will become more apparent after reading the detailed description of the present invention in conjunction with the accompanying drawings.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the embodiments. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

FIG. 1 is a flowchart of a first specific embodiment of the air conditioner control method disclosed in the present invention;

FIG. 2 is a flowchart of the second specific embodiment of the air conditioner control method disclosed in the present invention;

FIG. 3 is a schematic structural diagram of an air conditioner to which the air conditioner control method provided by the present invention is applied.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

The terms "first", "second", "third" and the like in the description and claims of the present invention and the accompanying drawings are used to distinguish different objects, rather than to describe a specific order. Furthermore, the terms "comprising" and "having", and any variations thereof, are meant to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes unlisted steps or units, or optionally also includes For other steps or units inherent to these processes, methods, products or devices.

In the present invention, an "embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they separate or alternative embodiments that are mutually exclusive with other embodiments. Those skilled in the art will appreciate that the embodiments described herein may be combined with other embodiments.

In view of the negligence of the installer, the failure of the shut-off valve itself or the communication failure, the air conditioner may be turned on directly under the condition that the valve is not fully opened. The specific control process of a newly designed air conditioner control method is shown in Figure 1. shown. This air conditioner control method protects the air conditioner while taking account of the user's air conditioner use requirements, and ensures that major components such as the system and the compressor are not damaged. By adopting this control method, the safety accident of refrigerant pipeline rupture and refrigerant leakage caused by unopened valve can be completely avoided. FIG. 3 is an internal structure diagram of an air conditioner to which the control method disclosed in the present invention is applied. Such an air conditioner 1 includes an indoor heat exchanger 10, an outdoor heat exchanger 11, a compressor 12, a throttle device 14, and a four-way valve 13 for switching the refrigerant flow direction according to different air conditioning modes. Wherein, the operating frequency of the compressor 12 can be continuously changed according to the change of the indoor air-conditioning load. For the convenience of description, the refrigerant passage between the indoor heat exchanger 10 and the outdoor heat exchanger 11 is defined as the first refrigerant passage, and the refrigerant passage between the outdoor heat exchanger 11 and the indoor heat exchanger 10 is defined as the first refrigerant passage. Two refrigerant passages. The shut-off valve for closing or opening the refrigerant circuit can be arranged on the first refrigerant passage or the second refrigerant passage, or as shown in FIG. 3 , between the first refrigerant passage and the second refrigerant passage. One independent working stop valve (17, 18) is respectively set on the agent passage. A pressure relief valve EEV19 is also provided in the refrigerant cycle, the first end of the pressure relief valve EEV19 is connected to the first refrigerant pipeline, and the second end of the pressure relief valve EEV19 is connected to the second refrigerant pipeline. The pressure relief valve EEV19 is preferably a solenoid valve, which can receive the electrical signal output by the controller of the air conditioner 1, so as to switch between the closed state and the open state under the control of the controller of the air conditioner 1, and reduce the pressure in the refrigerant pipeline. Instantaneous pressure. A first pressure sensor 15 is arranged at the exhaust end of the compressor 12 to detect the exhaust pressure at the exhaust end, and a second pressure sensor 16 is arranged at the return end of the compressor 12 to detect the return air pressure at the return end.

As shown in FIG. 1, in order to achieve the dual control effect of protection and use, the air conditioner control method disclosed in this embodiment includes the following steps:

When the air conditioner is turned on, in the first set period, the pressure detection value of the first pressure sensor at the exhaust end of the compressor is sampled and recorded as the first high pressure detection value. The pressure detection value of the second pressure sensor at the return air end of the compressor is sampled and recorded as the first low pressure detection value. A first pressure ratio is calculated, where the first pressure ratio is a ratio of the first high pressure detection value to the first low pressure detection value.

In the second set period that is continuous with the first set period, the pressure detection value of the first pressure sensor at the exhaust end of the compressor is sampled again, which is recorded as the second high pressure detection value. The pressure detection value of the second pressure sensor at the return air end of the compressor is sampled again, and recorded as the second low pressure detection value. A second pressure ratio is calculated, where the second pressure ratio is a ratio of the second high pressure detection value to the second low pressure detection value.

The compressor frequency change speed is determined according to the first pressure ratio and the second pressure ratio, and the operation of the compressor is controlled according to the compressor frequency change speed.

The durations of the first set period and the second set period are preferably selected according to the air conditioning capacity, and the duration of the first set period and the second set period are preferably set to be the same, so as to fully reflect the two consecutive Continuous variation of the system pressure ratio over a natural period. In the air conditioner control method shown in Fig. 1, through two cycles of continuous monitoring, it can be accurately determined whether the current compressor working state is adapted to the system pressure ratio, and the compression ratio in the next cycle can be determined according to the adaptation state. machine frequency change rate. Under the condition that the system pressure ratio is suitable, adjust the compressor frequency change speed appropriately with adjusting the air-conditioning room load as the primary goal; under the condition that the system pressure ratio is not suitable, actively intervene to change the compressor frequency change speed to form a dynamic The adjustment scheme ensures the stability and safety of the complex coupled air conditioning system composed of multiple components, multiple heat exchange processes and affected by multiple external conditions.

Controlling the operation of the compressor according to the changing speed of the frequency of the compressor may specifically adopt the manner shown in FIG. 2 . It is easy to understand that after the air conditioner is turned on, if the temperature difference between the ambient temperature of the current air-conditioned room and the temperature set by the user is large, the indoor air-conditioning load is large, and the compressor speed needs to increase rapidly; If the temperature difference between the set temperatures is small, the indoor air conditioning load is small, and the compressor speed needs to increase slowly. The rising speed of the fast frequency rise and the slow frequency rise is usually a fixed value, for example, the set frequency change is 2Hz/s when the frequency is rising rapidly, 1Hz/2s when the frequency is rising slowly, etc. The specific value of the speed is not limited here. . In the control method shown in FIG. 2 , after starting the machine, preferably the same control strategy is maintained, and the pressure detection value sampling in the first set period is started while the operation is started according to the temperature difference. After the first pressure ratio is obtained by sampling, the compressor frequency change speed is started to be intervened according to the system pressure ratio.

Specifically, the air-conditioning controller stores a one-to-one correspondence between the pressure ratio setting interval and the set compressor frequency change speed. This one-to-one correspondence follows the following rules, that is, the smaller the upper limit threshold of the pressure ratio setting interval, that is, the smaller the system pressure ratio, the allowable set compressor frequency change speed, especially the compressor frequency increase speed is greater. . An optional way is to set three set pressure ratio intervals. If the first pressure ratio belongs to the first set pressure ratio interval, the compressor frequency change speed is set as the first frequency increase speed; if the first pressure ratio belongs to the first set pressure ratio interval If the first pressure ratio belongs to the third set pressure ratio range, set the compressor frequency change speed to the third Upscaling speed. The first up-conversion speed is greater than the second up-conversion speed, and the second up-conversion speed is greater than or equal to the third up-conversion speed. The first upscaling speed can be set to 2Hz/s, the second upscaling speed can be set to 1Hz/s, and the third upscaling speed can be set to 1Hz/2s. It is also possible to set both the second up-conversion speed and the third up-conversion speed to 1Hz/2s. The first set pressure ratio section, the second set pressure ratio section and the third set pressure ratio section are continuous and the upper limit threshold value increases sequentially. For example, you can set the first set pressure ratio interval to be [1,3], the second set pressure ratio interval to be (3,6], and the third set pressure ratio interval to be (6,9]. At this stage, When the system is turned on by default, the air conditioner is running normally, and the compressor frequency needs to keep rising to eliminate the temperature difference between the air conditioner room temperature and the set temperature. After obtaining the first, second, and third upscaling speeds , the system does not intervene immediately. As shown in Figure 2, the system keeps the pressure sampling of the first pressure sensor and the second pressure sensor, and calculates the second pressure ratio, after obtaining the second pressure ratio, according to the second pressure ratio Calibrate and set the frequency change speed of the compressor, get the calibrated compressor frequency conversion speed, and control the compressor to run according to the calibrated compressor frequency conversion speed.

During the calibration process, the system no longer defaults that the compressor frequency needs to continue to maintain an upward trend, but fully considers the change of the system pressure ratio, and intervenes in the operation of the compressor according to the specific situation of the system pressure ratio, avoiding the original control mode. Execution without identifying the failure to open the valve will cause the system to frequently work at a level exceeding the pressure warning line, resulting in the rupture of the pipeline running at high pressure for a long time, resulting in a safety accident of refrigerant leakage. Calibrating and setting the compressor frequency change speed according to the second pressure ratio, and obtaining the calibrated compressor frequency conversion speed specifically includes the following steps:

If the second pressure ratio belongs to the first set pressure ratio range, it means that after starting up and running for a period of time, the system pressure ratio remains at a low level, the working state is stable, and the risk of safety accidents is small, that is, the set compressor frequency is maintained. The change speed is unchanged, that is, the calibrated compressor frequency conversion speed obtained in this step is equal to the set compressor frequency change speed, and the compressor is controlled to continue to run up frequency according to the established control strategy to meet the needs of adjusting the load of the air-conditioned room.

If the second pressure ratio belongs to the second set pressure ratio range, it means that after starting up and running for a period of time, the system pressure ratio is stable and maintained at a reasonable level. If the frequency continues to increase, the system pressure ratio may be too high. Control the compressor to no longer run at increased frequency, that is, the frequency conversion speed of the calibrated compressor obtained in this step is equal to 0, the compressor frequency will not increase, and the compressor is controlled to keep the current operating frequency unchanged and run at a fixed frequency to avoid the system pressure ratio. continue to rise.

If the second pressure ratio belongs to the third set pressure ratio range, it means that after starting up and running for a period of time, the system pressure ratio is at a high level, and the valve may not be opened. Frequency reduction speed, control the compressor to reduce frequency operation to reduce the system pressure ratio.

In the above steps, the frequency reduction speed is determined according to the magnitude of the system pressure ratio increase:

If within the first set period, the first pressure ratio belongs to the first set pressure ratio interval, then if it is further obtained that the second pressure ratio belongs to the third set pressure ratio range, it means that the system pressure ratio is higher after starting up and running for a period of time. Rapid increase, the risk of system failure is high, the set compressor frequency change speed, that is, the first frequency increase speed is calibrated to the first set frequency reduction speed, that is, at the end of the second set period, the frequency increase operation will not be performed , but to perform rapid frequency reduction operation, sacrificing the use of air conditioners, and giving priority to ensuring system security.

If in the first set period, the first pressure ratio belongs to the second set pressure ratio range, then if it is further obtained that the second pressure ratio belongs to the third set pressure ratio range, it means that the system pressure ratio is relatively large when it is just turned on. , and the system pressure ratio does not increase drastically, the set compressor frequency change speed, that is, the second frequency increase speed is calibrated to the second set frequency reduction speed, that is, at the end of the second set period, the frequency increase is not performed. Instead, it performs slow-speed down-frequency operation to give priority to ensuring system security while taking into account the needs of air-conditioning.

If within the first set period, the first pressure ratio belongs to the third set pressure ratio range, then if it is further obtained that the second pressure ratio belongs to the third set pressure ratio range, it means that the system pressure will not be affected for a period of time after the start-up. The ratio does not increase significantly but maintains a stable high pressure ratio condition, and the set compressor frequency change speed, that is, the third frequency increase speed is calibrated to the third set frequency reduction speed, that is, in the second set period At the end, instead of performing frequency-up operation, slow-speed down-frequency operation is performed to give priority to ensuring the safety of the system. At the same time, in the state of high pressure ratio, it still takes into account the needs of air conditioning.

Preferably, the absolute value of the first set frequency reduction speed is greater than the absolute value of the second set frequency reduction speed, and the absolute value of the second set frequency reduction speed is greater than or equal to the absolute value of the third set frequency reduction speed. The first set frequency reduction speed can be set to -2Hz/s, the second set frequency reduction speed can be set to -1Hz/s, and the third set frequency reduction speed can be set to -1Hz/2s. It is also possible to set both the second set frequency reduction speed and the third set frequency reduction speed to -1Hz/2s.

In the above-mentioned control process, the pre-intervention of the compressor frequency change speed is performed to avoid high-risk operating conditions. In practice, however, there are also more extreme operating conditions. Therefore, after calculating the first pressure ratio, it is specially set whether or not the first pressure ratio belongs to the protection pressure ratio range. If the first pressure ratio belongs to the protection pressure ratio range, the compressor is directly controlled to stop and the compressor frequency change speed is stopped to be calibrated and set according to the second pressure ratio. Wherein, the protection pressure ratio interval is continuous with the third set pressure ratio interval, and the lower limit threshold of the protection pressure ratio interval is greater than the upper limit threshold of the third set pressure ratio. The lower limit threshold of the protection pressure ratio interval can be set to be greater than 9.

While stopping the setting of the compressor frequency change speed according to the second pressure ratio calibration, the system still keeps monitoring the second pressure ratio. If the second pressure ratio belongs to the first set pressure ratio range, it means that the compressor is shut down and significantly reduced The system pressure ratio is controlled, no hardware intervention is required, and the compressor shuts down while keeping the pressure relief valve EEV closed. In this way, if the first pressure ratio exceeds the lower limit threshold of the protection set pressure ratio setting interval for a short time due to a drastic change in the load, the timely intervention can also ensure that the air conditioner can maintain the normal continuous operation under the condition of load elimination when the air conditioner is turned on again. Running state without additional waiting time. If the second pressure ratio does not belong to the first set pressure ratio range, the compressor is controlled to stop and the pressure relief valve EEV is controlled to open, and the pressure relief valve EEV is used to adjust the system pressure ratio.

Similarly, after the second pressure ratio is calculated, it is also first determined whether the second pressure ratio belongs to the protection pressure ratio range. If the second pressure ratio belongs to the protection pressure ratio interval, the compressor is controlled to stop. If both the first pressure ratio and the second pressure ratio are in the protection pressure ratio range, control the compressor to stop and control the relief valve EEV to open, and use the relief valve EEV to adjust the system pressure ratio.

A selectable value of the first pressure ratio, the second pressure ratio, the calibration compressor inverter speed and the working state of the pressure relief valve EEV is shown in the following table, where K1 represents the first pressure ratio, and K2 represents the second pressure ratio. , the first up-conversion speed V _up1 is greater than the second up-conversion speed V _up2 , the second up-conversion speed V _up2 is greater than or equal to the third up-conversion speed; the first set down-conversion speed V _down1 is greater than the second set down-conversion speed V _down2 , the second set frequency reduction speed V _down2 is greater than or equal to the third set frequency reduction speed V _down3 . That is to say, in two consecutive sampling periods, if the system pressure ratio falls within a lower range, the system keeps the frequency up; if the system pressure ratio falls within a reasonable range, the system keeps the frequency unchanged, while If the system pressure ratio falls within the higher range, the system remains underclocked. Therefore, while ensuring the reasonable operation of the air conditioner, the risk of the system is controlled to a reasonable level. For example, when the system pressure is relatively high, the compressor will not continue to operate at a high frequency, making the operation of the air conditioner safer.

It can be understood that the non-opening valve state is a kind of fault of the air conditioner. The frequency that occurs in the actual production and use process is relatively low. Therefore, for ordinary split air conditioners, it is still necessary to reduce and eliminate the temperature difference between the ambient temperature of the air-conditioned room and the temperature set by the user as the control system. The control target to control the operating frequency of the compressor, this control strategy has the highest priority. Preferably, in the process of frequency control with the temperature difference as the control target of the air conditioner, the pressure ratio is sampled according to the set sampling period, and if the pressure ratio falls within the protection pressure ratio range, the shutdown protection of the compressor is performed first, And then switch to determine the compressor frequency change speed according to the control method described in the above embodiment, and control the compressor operation according to the compressor frequency change speed.

The embodiment of the present application further provides an air conditioner, which applies the above air conditioner control method. For the specific steps of the air conditioner control method, refer to the detailed description of the above embodiments and the detailed description of the accompanying drawings. It is not repeated here, the air conditioner adopting the above air conditioner control method can achieve the same technical effect.

Embodiments of the present application further provide a computer storage medium, wherein the computer storage medium is stored in a computer program for electronic data exchange, and the computer program enables the air conditioner to execute part or all of the steps of any method described in the above method embodiments.

In the above-mentioned embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus may be implemented in other manners. For example, the apparatus embodiments described above are only illustrative. For example, the division of the above units or modules is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical or other forms.

The unit described above as a separate component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit, that is, it may be located in a physical space, or may be distributed to multiple network units, Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware, or may be implemented in the form of software functional units.

The above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art can still The recorded technical solutions are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions claimed in the present invention.

Claims (9)

1. An air conditioner control method is characterized by comprising the following steps:

the air conditioner is started, and in a first set period:

sampling a first high-pressure detection value of a compressor exhaust end;

sampling a first low-pressure detection value of an air return end of a compressor;

calculating a first pressure ratio that is a ratio of the first high pressure detection value and the first low pressure detection value;

in a second setting period consecutive to the first setting period:

sampling a second high-pressure detection value of the exhaust end of the compressor;

sampling a second low-pressure detection value of the air return end of the compressor;

calculating a second pressure ratio that is a ratio of the second high pressure detection value and the second low pressure detection value;

after the first pressure ratio is obtained, calling a corresponding set compressor frequency change speed according to the first pressure ratio;

after the second pressure ratio is obtained, calibrating the set compressor frequency change speed according to the second pressure ratio to obtain a calibrated compressor variable frequency speed;

and controlling the compressor to operate according to the variable frequency speed of the calibrated compressor.

2. The air conditioner control method according to claim 1, characterized in that:

invoking a corresponding set compressor frequency change speed based on the first pressure ratio comprises the steps of:

setting the frequency variation speed of the compressor to be a first frequency increasing speed if the first pressure ratio belongs to a first set pressure ratio interval;

if the first pressure ratio belongs to a second set pressure ratio interval, setting the frequency change speed of the compressor as a second frequency increasing speed;

setting the frequency variation speed of the compressor to be a third frequency increasing speed if the first pressure ratio belongs to a third set pressure ratio interval;

wherein the first up-conversion speed is greater than the second up-conversion speed, and the second up-conversion speed is greater than or equal to the third up-conversion speed; the first set pressure ratio interval, the second set pressure ratio interval and the third set pressure ratio interval are continuous, and the upper limit threshold value is increased in sequence.

3. The air conditioner control method according to claim 2, characterized in that:

calibrating the set compressor frequency variation speed according to the second pressure ratio to obtain a calibrated compressor variable frequency speed, comprising the following steps:

if the second pressure ratio belongs to a first set pressure ratio interval, keeping the frequency change speed of the set compressor unchanged, and controlling the frequency rising operation of the compressor when the frequency conversion speed of the calibrated compressor is equal to the frequency change speed of the set compressor;

if the second pressure ratio belongs to a second set pressure ratio interval, controlling the compressor to keep the current operation frequency unchanged and operate at a fixed frequency;

and if the second pressure ratio belongs to a third set pressure ratio interval, calibrating the set compressor frequency change speed to a set frequency reduction speed, and controlling the compressor to perform frequency reduction operation.

4. The air conditioner control method according to claim 3, characterized in that:

the method for calibrating the set compressor frequency change speed to the set frequency reduction speed comprises the following steps:

calibrating the set compressor frequency variation speed to a first set down-conversion speed if the first pressure ratio belongs to a first set pressure ratio interval within a first set period;

calibrating the set compressor frequency variation speed to a second set down-conversion speed if the first pressure ratio belongs to a second set pressure ratio interval within a first set period;

calibrating the set compressor frequency variation speed to a third set down-conversion speed if the first pressure ratio belongs to a third set pressure ratio interval within a first set period;

the absolute value of the first set frequency-reducing speed is greater than the absolute value of the second set frequency-reducing speed, and the absolute value of the second set frequency-reducing speed is greater than or equal to the absolute value of the third set frequency-reducing speed.

5. The air conditioner control method according to claim 4, wherein:

further comprising the steps of:

after the first pressure ratio is calculated, firstly, judging whether the first pressure ratio belongs to a protection pressure ratio interval, if the first pressure ratio belongs to the protection pressure ratio interval, controlling the compressor to stop and stopping calibrating the set compressor frequency change speed according to the second pressure ratio;

wherein the protection pressure ratio interval is contiguous with the third set pressure ratio interval, and a lower threshold of the protection pressure ratio interval is greater than an upper threshold of the third set pressure ratio.

6. The air conditioner control method according to claim 5, characterized in that:

further comprising the steps of:

further determining if the second pressure ratio falls within a first set pressure ratio interval if the first pressure ratio falls within a guard pressure ratio interval;

if the second pressure ratio belongs to a first set pressure ratio interval, controlling the compressor to stop and simultaneously keeping the pressure release valve closed;

a first end of the pressure relief valve is communicated with a first refrigerant passage, and a second end of the pressure relief valve is communicated with a second refrigerant passage; the first refrigerant passage is arranged between the indoor heat exchanger and the outdoor heat exchanger, the second refrigerant passage is arranged between the outdoor heat exchanger and the indoor heat exchanger, and a stop valve is arranged on the first refrigerant passage and/or the second refrigerant passage.

7. The air conditioner control method according to claim 1, characterized in that:

further comprising the steps of:

after the second pressure ratio is calculated, whether the second pressure ratio belongs to a protection pressure ratio interval or not is firstly determined, and if the second pressure ratio belongs to the protection pressure ratio interval, the compressor is controlled to stop.

8. The air conditioner control method according to claim 7, characterized in that:

further comprising the steps of:

if the first pressure ratio and the second pressure ratio are both in the protection pressure ratio interval, controlling the compressor to stop and controlling the pressure relief valve to open;

the first end of the pressure relief valve is communicated with a first refrigerant passage, the second end of the pressure relief valve is communicated with a second refrigerant passage, the first refrigerant passage is arranged between the indoor heat exchanger and the outdoor heat exchanger, the second refrigerant passage is arranged between the outdoor heat exchanger and the indoor heat exchanger, and the first refrigerant passage and/or the second refrigerant passage are/is provided with stop valves.

9. An air conditioner characterized by employing the air conditioner control method as claimed in any one of claims 1 to 8.

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