CN107677006B - Control method and system of air conditioner under low-humidity heating working condition - Google Patents

Abstract

The invention relates to the technical field of air conditioners, in particular to a control method and a control system of an air conditioner under a low-humidity heating working condition. The invention aims to solve the problem that the quick heating effect is poor due to long frequency rising time in the conventional starting frequency rising control method of the air conditioner. To this end, the control method of the present invention includes: acquiring the environmental humidity; when the environmental humidity is not greater than the set humidity, adjusting the expansion valve to a first target opening degree; starting the outer fan in the process of adjusting the expansion valve, and accelerating to a first target rotating speed; and starting the compressor at the same time, before or after the speed of the external fan is increased, and continuously increasing the frequency in stages according to a plurality of set speeds. The control method can greatly shorten the frequency rising time of the compressor while ensuring the normal oil return of the compressor, thereby achieving the purpose of rapid heating, improving the comfort of the air conditioner and improving the user experience.

Description

Control method and system of air conditioner under low-humidity heating condition

technical field

The invention relates to the technical field of air conditioners, in particular to a control method and system of an air conditioner under low-humidity heating conditions.

Background technique

With the increasing improvement of living standards, people's requirements for the quality of life are also getting higher and higher, and this requirement is particularly evident in household appliances. Taking an air conditioner as an example, in order to meet the user's demand for rapid heating and thus bring a more comfortable user experience, the existing air conditioner generally rapidly upsurges the compressor to a higher frequency when it is just turned on. When the compressor is running, the refrigerant in the compressor will be quickly discharged and circulated in the piping system. During the cycle, the lubricating oil will be discharged from the compressor together with the refrigerant and enter the pipeline. Only when the discharged lubricating oil smoothly returns to the compressor (ie, oil return) can the lubricating oil in the whole system be maintained. Dynamic balance, otherwise, the compressor will be damaged due to lack of oil. At present, most air conditioners on the market use the combination of oil separator and oil return capillary, and the lubricating oil discharged from the compressor is separated through the oil separator and then returned to the compressor through the oil return capillary. However, for inverter air conditioners, as the operating frequency of the compressor increases, the discharge speed/rate of the lubricating oil becomes faster and faster. When the discharge speed/rate of the lubricating oil exceeds the maximum oil return speed/rate of the oil return capillary , it is easy to produce the phenomenon of oil shortage. Therefore, in order to ensure normal oil return, in the process of the compressor rapidly rising to high frequency, the compressor is usually forced to run at a certain or some fixed frequency (oil return frequency) for a period of time, and continue to rise after the oil return is stable. frequency.

Although the above setting method ensures normal oil return, the setting method that forces the compressor to run continuously for a period of time at the oil return frequency makes the compressor's frequency increase time too long during the rapid heating process when the air conditioner is turned on, which slows down the compressor. The speed of reaching the maximum operating frequency also increases the time for rapid heating after the air conditioner is turned on, which in turn affects the effect of rapid heating of the air conditioner, bringing a bad user experience to the user. That is to say, there is a problem that the rapid heating effect is poor due to the long frequency increase time in the existing air conditioner startup control method.

Accordingly, there is a need in the art for a new air conditioner control method to solve the above problems.

SUMMARY OF THE INVENTION

In order to solve the above problems in the prior art, that is, in order to solve the problem of poor rapid heating effect due to long up-frequency time in the existing power-up frequency control method of an air conditioner, the present invention provides a low-humidity heating system. A control method of an air conditioner in a situation, the control method includes the following steps:

Get ambient humidity;

When the ambient humidity is not greater than the set humidity, adjusting the opening degree of the expansion valve of the air conditioner to the first target opening degree;

During the process of adjusting the opening degree of the expansion valve to the first target opening degree, the outdoor fan of the air conditioner is started, and the speed is accelerated to the first target rotation speed according to the set acceleration;

start the compressor of the air conditioner at the same time, before or after the speed of the outdoor fan starts to increase;

The compressor is continuously up-converted in stages according to a plurality of up-conversion speeds.

In the preferred technical solution of the above-mentioned control method for an air conditioner under low-humidity heating conditions, the control method further includes:

After continuously increasing the frequency in stages, determine whether the compressor frequency reaches the first target frequency;

When the compressor frequency reaches the first target frequency, the compressor is stopped from upscaling.

In the above preferred technical solution of the control method of the air conditioner under the low-humidity heating condition, the step of "adjusting the opening degree of the expansion valve of the air conditioner to the first target opening degree" further comprises:

reducing the opening degree of the expansion valve to the reference opening degree according to the set valve closing speed;

When the expansion valve opening degree reaches the reference opening degree, the expansion valve opening degree is increased to the first target opening degree according to the set valve opening speed.

In the preferred technical solution of the above-mentioned control method for an air conditioner under a low-humidity heating condition, "in the process of adjusting the opening degree of the expansion valve to the first target opening degree, start the outdoor fan of the air conditioner". The steps further include:

When the opening degree of the expansion valve reaches the reference opening degree, the outdoor fan is started.

In the above preferred technical solution of the control method of the air conditioner under the low-humidity heating condition, the step of “starting the compressor of the air conditioner at the same time, before or after the speed of the outdoor fan starts to increase” further includes:

The compressor of the air conditioner is started at the same time when the speed of the outdoor fan starts to increase.

In the preferred technical solution of the above-mentioned control method for an air conditioner under a low-humidity heating condition, the step of "making the compressor to continuously increase the frequency of the compressor in stages according to multiple set speeds" further includes:

causing the compressor to be up-converted according to the first up-conversion speed;

Determine whether the compressor frequency reaches the transition frequency;

When the frequency of the compressor reaches the transition frequency, the compressor is up-converted according to the second up-conversion speed;

Wherein, the transition frequency is less than the first target frequency.

In a preferred technical solution of the above-mentioned control method for an air conditioner under a low-humidity heating condition, the first frequency-raising speed is greater than the second frequency-raising speed; and/or the first target frequency is the compressor and/or the first target rotational speed is the maximum operating rotational speed of the outdoor fan; and/or the first target opening is the expansion valve opening that matches the first target frequency, And/or the set humidity is 60%.

In the preferred technical solution of the above-mentioned control method for an air conditioner under low-humidity heating conditions, the control method further includes:

Get environment parameters;

When the environmental parameter reaches the target parameter, down-converting the compressor to a second target frequency; and

reducing the rotational speed of the outdoor fan to a second target rotational speed; and

reducing the expansion valve opening to a second target opening;

The environmental parameter is the environmental temperature or the environmental humidity, and the target parameter is correspondingly the target temperature or the target humidity.

The present invention also provides a control system for an air conditioner under a low-humidity heating condition, the control system comprising:

an acquisition module, which is used to acquire ambient humidity;

The first control module is configured to reduce the opening degree of the expansion valve of the air conditioner to the reference opening degree according to the set valve closing speed when the ambient humidity is not greater than the set humidity, and when the expansion valve opens When the opening degree of the expansion valve reaches the reference opening degree, the opening degree of the expansion valve is increased to the first target opening degree according to the set valve opening speed;

a second control module, configured to start the outdoor fan when the opening degree of the expansion valve reaches the reference opening degree, and increase the speed to the first target speed according to the set acceleration;

The third control module is used to start the compressor of the air conditioner when the outdoor fan starts to increase speed, and make the compressor continuously increase the frequency in stages according to a plurality of set speeds, and when compressing When the frequency of the compressor reaches the first target frequency, the compressor stops the frequency increase;

A judgment module, which is used to judge whether the ambient humidity is not greater than the set humidity, whether the expansion valve reaches the reference opening, whether the outdoor fan starts to increase speed, and whether the compressor frequency reaches the first target frequency.

In the above preferred technical solution of the control system of the air conditioner under the low-humidity heating condition, the third control module causes the compressor to continuously increase the frequency of the compressor in stages according to a plurality of set speeds in the following manner:

the third control module causes the compressor to up-convert at a first up-conversion speed;

The judgment module judges whether the compressor frequency reaches the transition frequency;

When the compressor frequency reaches the transition frequency, the third control module causes the compressor to up-convert at a second up-conversion speed;

Wherein, the transition frequency is lower than the first target frequency; and/or the first up-conversion speed is greater than the second up-conversion speed.

In the preferred technical solution of the control system of the air conditioner under the above-mentioned low-humidity heating condition,

The acquisition module is also used to acquire environmental parameters;

The judging module is also used to judge whether the environmental parameter reaches the target parameter;

The first control module is further configured to reduce the rotational speed of the outdoor fan to a second target rotational speed when the environmental parameter reaches the target parameter;

The second control module is further configured to reduce the opening degree of the expansion valve to a second target opening degree when the environmental parameter reaches the target parameter;

The third control module is further configured to reduce the frequency of the compressor to a second target frequency when the environmental parameter reaches the target parameter;

The environmental parameter is the environmental temperature or the environmental humidity, and the target parameter is correspondingly the target temperature or the target humidity.

Those skilled in the art can understand that, in the preferred technical solution of the present invention, the control method of the air conditioner under the low-humidity heating condition includes: obtaining the ambient humidity; when the ambient humidity is not greater than the set humidity, opening the expansion valve of the air conditioner in the process of adjusting the opening degree of the expansion valve to the first target opening degree, the outdoor fan of the air conditioner is started, and the speed is accelerated to the first target speed according to the set acceleration; Start the compressor of the air conditioner at the same time, before or after the outdoor fan starts to increase speed; make the compressor continuously increase the frequency in stages according to multiple frequency increase speeds; judge whether the compressor frequency reaches the first target frequency; When the first target frequency is reached, the compressor is stopped to increase the frequency. As a preferred solution, when the opening degree of the expansion valve is reduced to the reference opening degree, the outdoor fan and the compressor are started at the same time. By canceling the continuous operation stage on the oil return frequency in the compressor frequency-up process, and instead enabling the compressor to continuously increase the frequency in stages at different frequency-up speeds after starting, the present invention can greatly shorten the compressor's frequency-up time , and then achieve the purpose of rapid heating, improve the comfort of the air conditioner, and improve the user experience. By obtaining the ambient humidity before the compressor starts, and when the ambient humidity is not greater than the set humidity, the expansion valve opening is first reduced to the reference opening, and then the compressor is reduced when the expansion valve opening is reduced to the reference opening. The setting method of starting at the same time with the outdoor fan, on the one hand, can make the compressor have a matching expansion valve opening before starting, and avoid the situation that the opening of the expansion valve does not match the compressor after the compressor starts; on the other hand, When the ambient humidity is low, the compressor can be started as soon as possible and the frequency will be increased, which omits the step of turning on the external fan for heat dissipation (to avoid rapid frost formation) before starting the compressor, which further shortens the compressor's frequency increase time. The heating effect after the compressor is started is improved.

Specifically, when the ambient humidity is not greater than the set humidity, first reduce the expansion valve to the reference opening, start the outdoor fan and the compressor at the same time when the expansion valve reaches the reference opening, and keep the outdoor fan at the maximum operating speed after the outdoor fan reaches the maximum operating speed. At this speed, after the compressor is started, the frequency is first increased according to the first frequency increase speed. When the compressor frequency reaches the transition frequency, the compressor frequency is increased according to the second frequency increase speed. When the compressor frequency reaches the first target frequency , so that the compressor stops boosting. Wherein, the transition frequency is lower than the first target frequency, and the first up-conversion speed is greater than the second up-conversion speed. Preferably, the first target frequency is the maximum operating frequency of the compressor. The inventor of the present application has found through repeated experiments that when the ambient humidity is not greater than the set humidity, the opening of the expansion valve is quickly reduced to the reference opening, and then the outdoor fan and the compressor are started simultaneously when the expansion valve reaches the reference opening. , and the speed of the outdoor fan is increased to the maximum working speed, and the compressor is up-converted in two or more stages at a frequency-up speed that is fast at first and then slow. It can also greatly shorten the time for the compressor to increase the frequency to the maximum operating frequency, so as to meet the needs of users for rapid heating.

Description of drawings

The method and system for controlling an air conditioner under a low-humidity heating condition of the present invention will be described below with reference to the accompanying drawings. In the attached picture:

1 is a schematic flowchart of a control method of an air conditioner under a low-humidity heating condition of the present invention;

2 is a schematic diagram showing the comparison of the frequency-up process of the compressor of the control method of the air conditioner under the low-humidity heating condition of the present invention and the compressor of the prior art;

3 is a schematic diagram of the control logic of the compressor, the outdoor fan and the expansion valve when the ambient humidity is not greater than 60% in the control method of the air conditioner under the low-humidity heating condition of the present invention.

Detailed ways

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principle of the present invention, and are not intended to limit the protection scope of the present invention. For example, although the present invention is described in conjunction with the embodiment in which the compressor is provided with two upscaling stages, this setting method is not static. Those skilled in the art can also apply the method of the present invention without departing from the principle of the present invention. For other application scenarios, such as compressors, three or more upscaling stages can also be set.

Referring first to FIG. 1 , FIG. 1 is a schematic flowchart of a control method of an air conditioner under a low-humidity heating condition according to the present invention.

As shown in FIG. 1 , in order to solve the problem of poor rapid heating effect due to long up-conversion time in the existing power-up frequency control method of an air conditioner, the present invention provides a control method for an air conditioner under low-humidity heating conditions. The control method mainly includes the following steps:

S100. Obtain the ambient humidity. For example, after the user presses the start switch of the air conditioner to turn on the air conditioner and selects the heating mode, the air conditioner obtains the ambient humidity through a hygrometer or a humidity sensor, where the ambient humidity may refer to the relative humidity of the outdoor environment;

S200. When the ambient humidity is not greater than the set humidity, adjust the opening degree of the expansion valve of the air conditioner to the first target opening degree. For example, when the ambient humidity is not greater than a certain relative humidity, adjust the opening degree of the expansion valve from step 480 to the first target opening degree. The valve speed is reduced to the reference opening, and then increases from the reference opening to the first target opening according to the valve opening speed. Preferably, the humidity is set to 60%, and the expansion valve is an electronic expansion valve or other devices that can control the opening. Expansion valve;

It should be noted that the opening adjustment of the electronic expansion valve is driven by a stepping motor, and the minimum angle range of the stepping motor rotation is called one step. Therefore, the opening adjustment of the electronic expansion valve is generally measured by "steps". . For example, the opening of the expansion valve is 200 steps. That is, the stepping motor drives the expansion valve to rotate to the 200th angle unit. Usually, when the air conditioner is in a closed state, in order to balance the system pressure, the expansion valve will have a large opening degree. For example, in the present invention, the opening degree of the expansion valve when the air conditioner is in a closed state can be 480 steps. The reference opening is the opening corresponding to the outdoor temperature and compressor frequency set according to the operating mode. The setting of the reference opening helps to establish the system pressure difference and realize the rapid cooling and rapid heating of the air conditioner. For example, the reference opening degree of the present invention can be 280 steps. That is to say, when the outdoor fan is started, the opening of the expansion valve is first reduced from 480 steps according to the valve closing speed such as 200P/s (ie 200 steps/second) to 280 steps, and then from 280 steps according to the valve opening speed such as 40P /s increases to the first target opening (eg, 400 steps).

S300. In the process of adjusting the opening degree of the expansion valve to the first target opening degree, start the outdoor fan of the air conditioner, and accelerate the speed to the first target rotation speed according to the set acceleration, preferably, when the opening degree of the expansion valve reaches the reference When opening, make the outdoor fan start according to the acceleration of 1000r/min per second, and reach the first target speed of 3000r/min in 3 seconds, preferably, the first target speed is the maximum working speed of the outdoor fan;

S400, start the compressor of the air conditioner at the same time as, before or after the speed of the outdoor fan starts to increase, preferably, start the compressor of the air conditioner when the speed of the outdoor fan starts to increase;

S500. Make the compressor continuously increase frequency in stages according to multiple set speeds. For example, after the compressor is started, make the compressor increase frequency according to the first frequency increase speed, and immediately after running to a certain frequency or running for a period of time Switch to the second upscaling speed to continue upscaling;

S600, judging whether the compressor frequency reaches the first target frequency, such as obtaining the current frequency of the compressor in real time, and comparing the current frequency with the first target frequency;

S700. When the frequency of the compressor reaches the first target frequency, stop the frequency boosting of the compressor. For example, when the current frequency reaches the first target frequency, keep the compressor at the first target frequency and continue to work. Preferably, the first target opening degree is the opening degree of the expansion valve that matches the first target frequency of the compressor, that is, in the process of continuously increasing the frequency of the compressor to the first target frequency in stages, the expansion valve opens The degree is also increased from the reference opening degree to the first target opening degree exactly.

It can be seen from the above description that the control method of the air conditioner of the present invention enables the expansion valve to start before the compressor when the ambient humidity is not greater than 60%, and starts the compressor and the outdoor fan at the same time when the expansion valve reaches the reference opening degree. On the one hand, the opening of the expansion valve can be matched with the working frequency of the compressor when it is started in advance, so as to avoid the situation that the opening of the expansion valve does not match the compressor caused by the expansion valve starting with the compressor. When the compressor is not large, the compressor can be started as soon as possible and the frequency will be increased. The step of turning on the external fan for heat dissipation (to avoid rapid frost formation) before starting the compressor is omitted, which further shortens the compressor's frequency-up time and improves the compressor frequency. Heating effect after startup. The control method of continuously increasing the frequency of the compressor in stages with different frequency-raising speeds after starting can further shorten the frequency-raising time of the compressor, improve the heating effect after the compressor is started, and achieve the purpose of rapid heating. In other words, the present invention cancels the process of continuous operation at the oil return frequency during the compressor frequency-up, and instead adjusts the expansion valve opening to the reference opening in advance, simultaneously starts the outdoor fan and the compressor, and controls the compressor rise and fall. The method of frequency speed can ensure the normal oil return of the compressor, and at the same time, it can also complete the rapid frequency increase of the compressor, which solves the problem of poor rapid heating effect caused by the long frequency increase time in the existing power-on frequency increase control method. It improves the comfort of the air conditioner and improves the user experience.

Of course, the first target rotational speed is not limited to the maximum working rotational speed. Under the circumstance that the heat dissipation condition of the compressor can be improved, those skilled in the art can set the first target rotational speed to any reasonable value so as to satisfy more specific requirements. For example, the first target speed may also be a certain speed value close to the maximum working speed of the outdoor fan or the maximum speed value that the outdoor fan can reach under the ambient temperature. Similarly, the setting of the ambient humidity is not limited to 60%. Those skilled in the art can adjust it based on different climatic conditions in different regions. For example, in a dry region, this value can be appropriately increased, and the set humidity can be set to 65. %, lower this value appropriately in humid areas, and set the set humidity to about 55%.

2, the principle of the present invention will be further explained. Among them, FIG. 2 is a schematic diagram showing the comparison of the frequency-up process of the compressor of the control method of the air conditioner under the low-humidity heating condition of the present invention and the compressor of the prior art. In FIG. 2, the solid line represents the frequency-up process of the compressor in the control method of the present invention, and the dashed line represents the frequency-up process of the compressor in the prior art.

As shown in Fig. 2, in the prior art, after the compressor is started, a fixed up-conversion speed V (such as 1 Hz/s) is generally used to up-convert, and in the up-conversion process, in order to ensure the normal oil return of the compressor, a The first oil return frequency f ₁ and the second oil return frequency f ₂ , when the compressor frequency is increased to the first oil return frequency f ₁ , the lubricating oil in the compressor is or will be in a state of oil shortage, so the compressor is here The frequency is maintained for a period of time to ensure the stable oil return of the compressor, and then continue to increase the frequency at the frequency increase speed V. Similarly, after the compressor is boosted to the second oil return frequency f ₂ , and maintained at this frequency for a period of time to ensure that the compressor returns to the oil stably, the frequency will continue to increase until the compressor reaches the maximum frequency f _max and then stop the boost. As described in the background art, such a frequency up-conversion method is maintained at the first oil return frequency f ₁ and the second oil return frequency f ₂ for a period of time, thus seriously affecting the frequency up-conversion speed of the compressor, although the stability of the compressor is ensured Return oil, but can not meet the needs of rapid heating well.

Continuing to refer to FIG. 2 , as a preferred embodiment of the present invention, the continuous upscaling process _of the compressor can be divided into two stages. Enter the second stage when the transition frequency is reached. The compressor in the second stage is up-converted at the second up-conversion speed V ₂ , and when the up-conversion reaches the first target frequency, the up-conversion is stopped. Preferably, the transition frequency can be set as the first oil return frequency f ₁ . The first up-conversion speed V ₁ is greater than the second up-conversion speed V ₂ . For example, the first up-conversion speed may be set to 1.2 Hz/s, and the second up-conversion speed may be set to 0.5 Hz/s.

That is to say, in the control method of the present invention, S500 may further include the following steps:

S510, causing the compressor to up-convert according to the _first up-conversion speed V1, for example, the control system of the air conditioner causes the compressor to up-convert at a frequency up-conversion speed of 1.2 Hz/s;

S520. Determine whether the compressor frequency reaches the transition frequency. For example, if the transition frequency is set as the first oil return frequency f ₁ , the control system determines whether the current frequency of the compressor reaches the first oil return frequency f ₁ ;

S530. When the compressor frequency reaches the transition frequency f1, the compressor is up _- converted according to the _second up-frequency speed V2. For example, when the control system determines that the current frequency of the compressor reaches f1, the compressor is up _- converted according to 0.5Hz/ The frequency increase speed of s continues to increase frequency to ensure the stable oil return of the compressor and the continuous frequency increase to complete the rapid heating of the air conditioner.

Preferably, the transition frequency f ₁ is smaller than the first target frequency, and the first target frequency is set to the maximum operating frequency f _max of the compressor.

The advantage of the above control method is that: by controlling the up-frequency speed of the compressor during the up-conversion process, the speed/rate of the lubricating oil discharged from the compressor also occurs correspondingly during the up-conversion process of the compressor at different up-conversion speeds. Change, and then adapt to the oil return speed/rate of the oil return capillary to ensure the stability of the oil return of the compressor. Specifically, by changing the up _- conversion speed of the compressor at the transition frequency f1, that is, the control method of up-conversion in two stages with a fast up-conversion speed first and then a slow up-conversion speed, the compressor can be up-converted at the first up-conversion speed. When the frequency of V ₁ is increased, the speed/rate of the lubricating oil discharged from the compressor reaches or exceeds the oil return speed/rate of the oil return capillary, and the lubricating oil in the compressor gradually decreases. When the transition frequency f1 is reached, the compressor turns to upscaling according to the _second upscaling speed V2. At this time, the lubricating oil flowing out _of the compressor is greatly reduced, and the speed/rate at which the lubricating oil is discharged from the compressor is less than the return rate of the oil return capillary. Oil velocity/velocity, and thus the amount of lubricating oil in the compressor, is guaranteed. That is to say, the present invention can ensure the normal oil return of the compressor through the change of the frequency increase speed, and at the same time, by canceling the control method of the continuous operation stage on the oil return frequency, the frequency increase speed of the compressor is correspondingly accelerated, so that the compressor can be faster The ground is up-converted to the maximum operating frequency, and then runs at the maximum operating frequency to meet the needs of users for rapid heating. Referring to FIG. 2 , it can be clearly seen that, after repeated experiments by the inventor, the time for the compressor of the present invention to reach the maximum operating frequency is significantly shorter than the time for the compressor in the prior art to reach the maximum operating frequency.

It should be pointed out that the above-mentioned preferred control methods and specific numerical values are only used to illustrate the principle of the present invention, and are not intended to limit the protection scope of the present invention. The parameters can be adjusted in any form, as long as the adjusted technical solution can improve the frequency-up speed condition on the premise of ensuring the normal oil return of the compressor. For example, the up-frequency stage can be further divided into three stages, each stage is up-converted at a different up-frequency speed (such as fast, slow and fast); the transition frequency can also fluctuate up and down according to the first oil return frequency; The target frequency is not the maximum operating frequency of the compressor, but a value close to the maximum operating frequency, or the like.

In addition, in order to better improve the user's experience of using the air conditioner, when the compressor operates at the maximum operating frequency, the air conditioner control method of the present invention may further include the following steps:

S800. Acquire environmental parameters, such as acquiring the current ambient temperature (such as indoor/outdoor temperature);

S900. When the environmental parameter reaches/closes to the target parameter, reduce the frequency of the compressor to the second target frequency, reduce the rotational speed of the outdoor fan to the second target rotational speed, and reduce the opening of the expansion valve to the second target opening, such as When the indoor temperature reaches the target temperature set by the user or is close to the target temperature, reduce the frequency of the compressor to the rated operating frequency or to the operating frequency that matches the external ambient temperature, and reduce the speed of the outdoor fan to the rated operating speed or The operating speed that matches the compressor, and the opening of the expansion valve is reduced to an opening that matches the current operating frequency of the compressor.

The advantage of this setting is that after the air conditioner is rapidly heating for a period of time, the indoor temperature will rise accordingly. When the ambient indoor temperature reaches/closes to the temperature set by the user, the compressor does not need to continue to work at the maximum operating frequency, and the outdoor fan will naturally There is no need to work at the maximum speed for heat dissipation, and the expansion valve does not need to work at the first target opening degree matching the compressor. At this time, reduce the frequency of the compressor to the rated working frequency or a working frequency that is more suitable for the current outdoor environment (such as outdoor temperature), and reduce the speed of the outdoor fan to the rated working speed or a speed that matches the compressor, and The opening of the expansion valve is reduced to match the opening of the compressor, which not only ensures the normal operation of the air conditioner, but also effectively prolongs the working life of the compressor, the outdoor fan and the expansion valve.

Of course, the environmental parameters and the corresponding target parameters are not static, and may also be environmental humidity (eg, outdoor humidity), target humidity set by the user, and the like.

The present invention also provides a control system for an air conditioner under a low-humidity heating condition, the control system mainly includes:

The collection module is used to obtain the ambient humidity. For example, after the air conditioner is turned on and the heating mode is selected, the collection module collects the relative humidity of the outdoor environment;

The first control module is used to reduce the opening of the expansion valve of the air conditioner to the reference opening according to the set valve closing speed when the ambient humidity is not greater than the set humidity, and when the opening of the expansion valve reaches the reference opening , so that the opening degree of the expansion valve increases to the first target opening degree according to the set valve opening speed;

The second control module is used to start the outdoor fan when the opening degree of the expansion valve reaches the reference opening degree, and accelerate to the first target speed according to the set acceleration;

The third control module is used to start the compressor when the outdoor fan starts to increase speed, and make the compressor continuously increase the frequency in stages according to multiple set speeds, and when the compressor frequency reaches the first target frequency, stop the compressor from upscaling;

The judgment module is used for judging whether the ambient humidity is not greater than the set humidity, whether the expansion valve reaches the reference opening degree, whether the outdoor fan starts to increase speed, and whether the compressor reaches the first target frequency.

Among them, the third control module makes the compressor continuously increase the frequency in stages according to multiple set speeds:

The third control module makes the compressor perform frequency upscaling according to the _first upscaling speed V1;

The judgment module judges whether the compressor frequency reaches the transition frequency f ₁ ;

When the compressor frequency reaches the transition frequency f1, the third control module makes the compressor perform frequency upscaling according to the _second upscaling speed V2 _;

Preferably, the first up-conversion speed V ₁ is greater than the second up-conversion speed V ₂ , the transition frequency f ₁ is smaller than the first target frequency, and the first target frequency is the maximum operating frequency f _max of the compressor, and the first target opening is Expansion valve opening that matches the maximum operating frequency f _max .

In addition, the acquisition module is also used to obtain environmental parameters, such as real-time acquisition of outdoor/indoor temperature and outdoor/indoor humidity using temperature/humidity sensors;

After the acquisition module obtains the environmental parameters, the judgment module is further used to judge whether the environmental parameters reach the target parameters, for example, the target parameters are the heating target temperature set by the user, etc.;

The first control module is also used to reduce the opening of the expansion valve to the second target opening when the environmental parameter reaches the target parameter; the second control module is also used to reduce the rotational speed of the outdoor fan when the environmental parameter reaches the target parameter to the second target speed; the third control module is also used to reduce the compressor frequency to the second target frequency when the environmental parameters reach the target parameters; for example, when the indoor temperature reaches the target temperature set by the user, the third control module first The compressor is reduced to the rated working frequency, and then the second control module reduces the speed of the outdoor fan to the rated working speed, and the first control module reduces the opening of the expansion valve to an opening that matches the rated working frequency of the compressor.

Those skilled in the art can understand that the physical forms of the first control module, the second control module, the third control module and the judgment module may be independent of each other, and of course may also be functional units integrated into one physical module. For example, a control system of an air conditioner includes a memory and a processor, and a computer program stored in the memory and executable on the processor, the computer program can complete the above-mentioned first control module, second control module, third control module and judgment module. Function.

The control method of the air conditioner and the working principle of the system under the low-humidity heating condition of the present invention will be briefly described below with reference to FIG. 3 . 3 is a schematic diagram of the control logic of the compressor, the outdoor fan and the expansion valve when the ambient humidity is not greater than 60% in the control method of the air conditioner under the low-humidity heating condition of the present invention.

As shown in Figure 3, when the air conditioner is in the heating mode, the working process of the outdoor fan, expansion valve and compressor can be as follows:

Turn on the air conditioner to heat up → obtain the outdoor relative humidity → when the outdoor relative humidity is not more than 60%, the expansion valve starts to reduce the opening degree from the opening degree B ₁ ' according to the valve closing speed V ₂₁ ' → after the time interval T ₁ , the expansion valve When the opening degree reaches the reference opening degree B' ₂ , the compressor and the outdoor fan are started at the same time, the expansion valve increases the opening degree according to the valve opening speed V ₂₂ ', wherein the compressor is up-frequency according to the frequency-up speed V ₁₁ ', and the outdoor fan is up-frequency according to the acceleration a ₁ 'increase the speed and keep running at the maximum working speed when it reaches the maximum working speed n ₁ '→when the compressor frequency reaches the transition frequency _{f 1 '} after the time interval of T2, continue to increase the frequency at the frequency increasing speed V ₁₂ ', and the expansion valve Continue to increase the opening degree according to the valve opening speed V ₂₂ ′ → after the time interval T ₃ , the compressor frequency reaches the maximum operating frequency f ₂ ' and stops the frequency increase, and the opening degree of the expansion valve reaches B ₃ ' matching f ₂ ' and stabilizes At this opening _→ after the time interval T4, the indoor temperature reaches the user's set temperature, the compressor reduces the frequency at the frequency reduction speed V ₁₃ ', and the outdoor fan reduces the speed at the acceleration a ₂ ' at the same time, and the expansion valve closes at the valve speed V ₂₃ 'Reduce the opening degree → After the time interval of T5, the compressor frequency is reduced to the rated working frequency f ₃ ' and maintained at this frequency, while the external fan speed is reduced to the rated working speed _{n 1 '} and maintained at this frequency, the expansion valve The opening is reduced to _B'4 matching _f3 ' and maintained at this frequency.

In the above preferred embodiment, the control method of the air conditioner mainly includes: obtaining the outdoor relative humidity; when the relative humidity is not greater than 60%, reducing the opening degree of the expansion valve to the reference opening degree according to the set valve closing speed; When the reference opening is reached, start the compressor and the outdoor fan at the same time. The valve opening speed is increased to the opening degree that matches the compressor frequency; it is judged whether the compressor frequency reaches the maximum working frequency; when the compressor frequency reaches the maximum working frequency, the frequency increase is stopped, and the expansion valve reaches the maximum working frequency. matching opening. Wherein, the first up-conversion speed is greater than the second up-conversion speed. The control system of the air conditioner includes a first control module, a second control module, a third control module, a judgment module and a collection module. By adjusting the expansion valve first when the relative humidity is not more than 60%, when the opening of the expansion valve is reduced to the reference opening, the compressor and the outdoor fan are started at the same time, the opening of the expansion valve is increased to the opening degree matching the compressor, And a control method for making the compressor perform frequency upscaling in two stages with a fast upscaling speed and then a slow downscaling speed, so that the expansion valve of the present invention can be matched with the frequency when the compressor is started in advance, realize the quick start of the compressor, and through The change of the compressor's frequency-up speed ensures that the compressor can return to the normal oil, and at the same time, it can also quickly increase the frequency to the maximum operating frequency, and then run at the maximum operating frequency to meet the user's demand for rapid heating and improve the user experience.

So far, the technical solutions of the present invention have been described with reference to the preferred embodiments shown in the accompanying drawings, however, those skilled in the art can easily understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims (10)

1. A control method of an air conditioner under a low-humidity heating working condition is characterized by comprising the following steps:

acquiring the environmental humidity;

when the environmental humidity is not greater than the set humidity, adjusting the opening degree of an expansion valve of the air conditioner to a first target opening degree;

in the process of adjusting the opening degree of the expansion valve to the first target opening degree, starting an external fan of the air conditioner, and accelerating to a first target rotating speed according to a set acceleration;

starting a compressor of the air conditioner at the same time, before or after the outer fan starts to increase the speed;

and continuously increasing the frequency of the compressor in stages according to a plurality of increasing frequency speeds.

2. The control method of the air conditioner under the low-humidity heating working condition according to claim 1, further comprising:

after the frequency is continuously increased in stages, judging whether the frequency of the compressor reaches a first target frequency;

stopping the compressor from increasing frequency when the compressor frequency reaches the first target frequency.

3. The method as claimed in claim 2, wherein the step of adjusting the opening degree of the expansion valve of the air conditioner to a first target opening degree further comprises:

reducing the opening degree of the expansion valve to a reference opening degree according to a set valve closing speed;

when the expansion valve opening degree reaches the reference opening degree, the expansion valve opening degree is increased to the first target opening degree at a set valve opening speed.

4. The method as claimed in claim 3, wherein the step of starting an external fan of the air conditioner in the process of adjusting the opening degree of the expansion valve to the first target opening degree further comprises:

and when the opening degree of the expansion valve reaches the reference opening degree, starting the outer fan.

5. The method for controlling the air conditioner under the low-humidity heating condition according to claim 4, wherein the step of starting the compressor of the air conditioner at the same time, before or after the speed of the external air blower is increased further comprises:

and starting a compressor of the air conditioner while the outer fan starts to increase the speed.

6. The method as claimed in claim 2, wherein the step of "enabling the compressor to continuously increase the frequency in stages at a plurality of set speeds" further comprises:

enabling the compressor to perform frequency boosting according to a first frequency boosting speed;

judging whether the frequency of the compressor reaches a transition frequency;

when the frequency of the compressor reaches the transition frequency, the compressor is enabled to carry out frequency raising according to a second frequency raising speed;

wherein the transition frequency is less than the first target frequency.

7. The control method of the air conditioner under the low humidity heating condition as claimed in claim 6,

the first frequency increasing speed is greater than the second frequency increasing speed; and/or

The first target frequency is a maximum operating frequency of the compressor; and/or

The first target rotating speed is the maximum working rotating speed of the outer fan; and/or

The first target opening degree is an expansion valve opening degree matched with the first target frequency, and/or

The set humidity was 60%.

8. The control method of the air conditioner under the low-humidity heating condition according to any one of claims 1 to 7, further comprising:

acquiring an environmental parameter;

when the environmental parameter reaches a target parameter, the compressor is subjected to frequency reduction to a second target frequency; and is

Reducing the rotating speed of the outer fan to a second target rotating speed; and is

Decreasing the expansion valve opening to a second target opening;

the environment parameter is an environment temperature or the environment humidity, and the target parameter is a target temperature or a target humidity correspondingly.

9. A control system of an air conditioner under a low humidity heating working condition is characterized by comprising:

the acquisition module is used for acquiring the environmental humidity;

a first control module, configured to reduce an opening degree of an expansion valve of the air conditioner to a reference opening degree at a set valve closing speed when the ambient humidity is not greater than a set humidity, and increase the opening degree of the expansion valve to a first target opening degree at a set valve opening speed when the opening degree of the expansion valve reaches the reference opening degree;

the second control module is used for starting an external fan of the air conditioner and accelerating the external fan to a first target rotating speed according to a set acceleration when the opening degree of the expansion valve reaches the reference opening degree;

the third control module is used for starting a compressor of the air conditioner while the external fan starts to increase the speed, continuously increasing the frequency of the compressor in stages according to a plurality of set speeds, and stopping increasing the frequency of the compressor when the frequency of the compressor reaches a first target frequency;

and the judging module is used for judging whether the environment humidity is not greater than the set humidity, whether the opening of the expansion valve reaches the reference opening, whether the outer fan starts to increase the speed and whether the frequency of the compressor reaches the first target frequency.

10. The control system of an air conditioner under low humidity heating condition as claimed in claim 9, wherein the third control module makes the compressor frequency up-converted in stages and continuously according to a plurality of set speeds according to the following manner:

the third control module enables the compressor to carry out frequency increasing according to the first frequency increasing speed;

the judging module judges whether the frequency of the compressor reaches a transition frequency;

when the frequency of the compressor reaches the transition frequency, the third control module enables the compressor to carry out frequency increasing according to a second frequency increasing speed;

wherein the transition frequency is less than the first target frequency; and/or

The first frequency-increasing speed is greater than the second frequency-increasing speed.

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