CN106885348B

CN106885348B - Air conditioner and control method

Info

Publication number: CN106885348B
Application number: CN201710239021.2A
Authority: CN
Inventors: 罗荣邦
Original assignee: Qingdao Haier Air Conditioner Gen Corp Ltd
Current assignee: Qingdao Haier Air Conditioner Gen Corp Ltd; Haier Smart Home Co Ltd; Qingdao Haier Jiaozhou Air Conditioner Co Ltd
Priority date: 2017-04-13
Filing date: 2017-04-13
Publication date: 2020-08-25
Anticipated expiration: 2037-04-13
Also published as: CN106885348A

Abstract

The invention discloses an air conditioner and a control method, and belongs to the technical field of air conditioners. The air conditioner comprises a controller, a first temperature sensor for detecting the outdoor environment temperature and a variable-capacity compressor assembly for driving refrigerant to circulate, wherein the variable-capacity compressor assembly comprises a variable-capacity compressor, and the operation modes of the variable-capacity compressor comprise a two-stage mode and a double-cylinder mode; the controller is used for: controlling the air conditioner to perform refrigeration operation; acquiring the outdoor environment temperature detected by a temperature sensor; and when the outdoor environment temperature is greater than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor. The air conditioner adopts the variable-capacity compressor, and can flexibly adjust the operation mode and the operation frequency of the variable-capacity compressor according to the outdoor temperature, so that the compression efficiency of the variable-capacity compressor on the refrigerant and the output refrigerant quantity can be matched with the current outdoor temperature condition, and the operation energy efficiency of the air conditioner during the refrigeration operation is improved.

Description

Air conditioner and control method

Technical Field

The invention relates to the technical field of air conditioners, in particular to an air conditioner and a control method.

Background

The conventional air conditioner mostly adopts a mechanical compressor to perform compression operation of temperature rise and pressure rise on a refrigerant, such as a piston compressor, a screw compressor, a centrifugal compressor, a linear compressor and the like, and can be divided into a single-cylinder compressor, a double-cylinder compressor and a multi-cylinder compressor according to the number of compression cylinder bodies in the compressor, wherein for the double-cylinder compressor and the multi-cylinder compressor with the number of cylinder bodies not less than one, the compression process is that multistage compression operation is sequentially performed on the refrigerant according to the connection sequence among the multiple cylinder bodies. When the air conditioner normally operates, the compressor can only raise and boost the temperature and the pressure of a refrigerant according to a fixed single compression sequence mode, but due to the influence of various factors such as outdoor ambient temperature, indoor temperature and the like, the air conditioner has different requirements on the operating frequency, the compression efficiency and the like of the compressor under different working conditions, so that the conventional compressor often has useless power consumption when operating in a single compression mode and cannot reach the optimal energy efficiency operating state of the air conditioner.

Disclosure of Invention

The invention provides an air conditioner and a control method, and aims to solve the problem of operation energy efficiency of the air conditioner. The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview and is intended to neither identify key/critical elements nor delineate the scope of such embodiments. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.

According to the first aspect of the present invention, there is also provided a control method of an air conditioner, characterized in that the control method includes: controlling the air conditioner to perform refrigeration operation; acquiring the outdoor environment temperature detected by a temperature sensor; and when the outdoor environment temperature is greater than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor.

The control method further comprises the following steps: acquiring indoor environment temperature and target refrigerating temperature set by a user; determining a temperature difference value between the indoor environment temperature and the target refrigerating temperature; when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a first frequency modulation rate; otherwise, controlling the variable capacity compressor to reduce the running frequency of the variable capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

Further, the control method comprises the following steps: and when the outdoor environment temperature is less than the temperature threshold value, controlling the variable capacity compressor to operate in a two-stage mode, and increasing the operating frequency of the variable capacity compressor.

Further, the control method further comprises: acquiring indoor environment temperature and target refrigerating temperature set by a user; determining a temperature difference value between the indoor environment temperature and the target refrigerating temperature; when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to increase the running frequency of the variable-capacity compressor at a first frequency modulation rate; otherwise, controlling the variable capacity compressor to increase the running frequency of the variable capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

Further, according to a second aspect of the present invention, there is provided an air conditioner, the air conditioner including a controller, a first temperature sensor for detecting an outdoor ambient temperature, and a variable capacity compressor assembly for driving a refrigerant to circulate, the variable capacity compressor assembly including a variable capacity compressor, an operation mode of the variable capacity compressor including a two-stage mode and a two-cylinder mode; the controller is used for: controlling the air conditioner to perform refrigeration operation; acquiring the outdoor environment temperature detected by a temperature sensor; and when the outdoor environment temperature is greater than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor.

Further, the variable capacity compressor assembly comprises a variable capacity compressor and a first four-way valve; the air conditioner comprises an indoor heat exchanger, an outdoor heat exchanger, a second four-way valve and a throttling device; the variable-capacity compressor assembly is connected with the indoor heat exchanger, the outdoor heat exchanger, the second four-way valve and the throttling device through refrigerant pipelines to form a refrigerant circulating pipeline.

Further, the air conditioner also comprises a gas-liquid separator connected with the refrigerant circulating pipeline, and the gas-liquid separator comprises a first outlet and a second outlet; the variable-capacity compressor comprises a first compression cylinder and a second compression cylinder, the first compression cylinder is provided with a first air inlet and a first air outlet, the second compression cylinder is provided with a second air inlet and a second air outlet, the first air inlet is communicated with the first outlet of the gas-liquid separator, and the second air outlet of the second compression cylinder is communicated with the exhaust port of the variable-capacity compressor; the first four-way valve comprises a valve body, a valve block arranged in a valve cavity in the valve body, a first interface, a second interface, a third interface and a fourth interface, wherein the valve block is provided with a first valve position for communicating the first interface with the second interface and communicating the third interface with the fourth interface, and a second valve position for communicating the second interface with the third interface and blocking the first interface and the fourth interface; the first interface is communicated with a second outlet of the gas-liquid separator, the second interface is communicated with a second gas inlet, the third interface is communicated with a first gas outlet, and the fourth interface is communicated with a gas outlet; controlling a variable capacity compressor to operate in a two cylinder mode, comprising: controlling a valve block of the first four-way valve to be switched to a first valve position; controlling a variable capacity compressor to operate in a two-stage mode, comprising: and controlling the valve block of the first four-way valve to be switched to the second valve position.

Further, the gas-liquid separator comprises an inlet; the second four-way valve comprises a valve body, a valve block arranged in a valve cavity in the valve body, a first interface, a second interface, a third interface and a fourth interface, wherein the valve block is provided with a first valve position communicated with the first interface and the fourth interface and the second interface and the third interface, and a second valve position communicated with the first interface and the second interface and the third interface and the fourth interface; the first interface is communicated with the outdoor heat exchanger, the second interface is communicated with the outlet of the gas-liquid separator, the third interface is communicated with the indoor heat exchanger, and the fourth interface is communicated with the exhaust port; when the air conditioner operates in a refrigerating mode, the valve block of the second four-way valve is located at the first valve position.

According to a third aspect of the present invention, there is also provided a control method of an air conditioner, the control method including: controlling the heating operation of the air conditioner; acquiring the outdoor environment temperature detected by a temperature sensor; and when the outdoor environment temperature is less than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor.

Further, the control method further comprises: acquiring indoor environment temperature and target heating temperature set by a user; determining a temperature difference value between a target heating temperature and an indoor environment temperature; when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a first frequency modulation rate; otherwise, controlling the variable capacity compressor to reduce the running frequency of the variable capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

Further, the control method further comprises: and when the outdoor environment temperature is greater than the temperature threshold value, controlling the variable capacity compressor to operate in a two-stage mode, and increasing the operating frequency of the variable capacity compressor.

Further, the control method further comprises: acquiring indoor environment temperature and target heating temperature set by a user; determining a temperature difference value between a target heating temperature and an indoor environment temperature; when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to increase the running frequency of the variable-capacity compressor at a first frequency modulation rate; otherwise, controlling the variable capacity compressor to increase the running frequency of the variable capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

According to a fourth aspect of the present invention, there is also provided an air conditioner, the air conditioner including a controller, a first temperature sensor for detecting an outdoor ambient temperature, and a variable capacity compressor assembly for driving a refrigerant to circulate, the variable capacity compressor assembly including a variable capacity compressor, operating modes of the variable capacity compressor including a two-stage mode and a two-cylinder mode; the controller is used for: controlling the heating operation of the air conditioner; acquiring the outdoor environment temperature detected by a temperature sensor; and when the outdoor environment temperature is less than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor.

Further, the gas-liquid separator comprises an inlet; the second four-way valve comprises a valve body, a valve block arranged in a valve cavity in the valve body, a first interface, a second interface, a third interface and a fourth interface, wherein the valve block is provided with a first valve position communicated with the first interface and the fourth interface and the second interface and the third interface, and a second valve position communicated with the first interface and the second interface and the third interface and the fourth interface; the first interface is communicated with the outdoor heat exchanger, the second interface is communicated with the outlet of the gas-liquid separator, the third interface is communicated with the indoor heat exchanger, and the fourth interface is communicated with the exhaust port; when the air conditioner is in heating operation, the valve block of the second four-way valve is in the second valve position.

The air conditioner adopts the variable-capacity compressor, and can flexibly adjust the operation mode and the operation frequency of the variable-capacity compressor according to the outdoor temperature, so that the compression efficiency of the variable-capacity compressor on the refrigerant and the output refrigerant quantity can be matched with the current outdoor temperature condition, and the operation energy efficiency of the air conditioner during the refrigeration operation is improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.

FIG. 1 is a flowchart illustrating operation of the control method of the present invention during cooling conditions in the summer according to an exemplary embodiment;

FIG. 2 is a flowchart illustrating operation of the control method of the present invention during winter heating conditions in accordance with an exemplary embodiment;

fig. 3 is a schematic structural view of an air conditioner according to the present invention shown in an exemplary embodiment.

11, an outdoor heat exchanger;

12. a variable capacity compressor; 121. a first compression cylinder; 122. a second compression cylinder; 123. a first port; 124. a second port; 125. a third port; 126. a fourth port; 127. an exhaust port;

1211. a first air inlet; 1212. a first air outlet;

1221. a second air inlet; 1222. a second air outlet;

because the first four-way valve and the second four-way valve are arranged at a plurality of interfaces, the interfaces with the same name of different four-way valves are distinguished by adopting different reference numerals, and the method comprises the following specific steps:

13. a first four-way valve; 131. a first interface; 132. a second interface; 133. a third interface; 134. a fourth interface;

14. a second four-way valve: 141. a first interface; 142. a second interface; 143. a third interface; 144. a fourth interface;

16. a gas-liquid separator; 161. a first outlet; 162. a second outlet;

21. an indoor heat exchanger; 22. a throttling device.

Detailed Description

The following description and the drawings sufficiently illustrate specific embodiments of the invention to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. The examples merely typify possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in or substituted for those of others. The scope of embodiments of the invention encompasses the full ambit of the claims, as well as all available equivalents of the claims. Embodiments may be referred to herein, individually or collectively, by the term "invention" merely for convenience and without intending to voluntarily limit the scope of this application to any single invention or inventive concept if more than one is in fact disclosed. Herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method or apparatus that comprises the element. The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. As for the methods, products and the like disclosed by the embodiments, the description is simple because the methods correspond to the method parts disclosed by the embodiments, and the related parts can be referred to the method parts for description.

As shown in fig. 3, the present invention provides an air conditioner, which includes an indoor unit and an outdoor unit, wherein the outdoor unit is provided with a first temperature sensor for detecting an outdoor environment temperature, so as to detect a current outdoor environment temperature in real time; meanwhile, the outdoor unit is also provided with a variable capacity compressor assembly for driving the refrigerant to circulate, and the variable capacity compressor assembly can compress the refrigerant in the refrigerant circulation pipeline of the air conditioner and provides power for the refrigerant to circularly flow between the indoor unit and the outdoor unit.

The variable capacity compressor assembly includes a variable capacity compressor 12, in an embodiment, the variable capacity compressor 12 includes at least two compression cylinders, and each compression cylinder can independently perform a compression operation on a refrigerant; when the air conditioner operates under different temperature and humidity working conditions, the air conditioner also has corresponding requirements on the refrigerant flowing in the refrigerant circulation pipeline, for example, when the indoor and outdoor temperature is lower in winter, a compressor is required to output more refrigerants in order to accelerate the heating efficiency of the air conditioner; or when the indoor temperature is close to the heating temperature set by the user in winter, the compressor is required to compress the refrigerant at a higher compression ratio in order to improve the energy efficiency of the air conditioner. Therefore, the operation modes of the variable capacity compressor 12 adopted by the invention comprise a two-stage mode and a two-cylinder mode, wherein when the variable capacity compressor 12 operates in the two-stage mode, the refrigerant flowing through the variable capacity compressor 12 is sequentially compressed by each compression cylinder body, and the refrigerant subjected to multi-stage compression is output to the refrigerant circulation pipeline, so that the compression ratio of the refrigerant can be improved, and the two-stage mode is suitable for the conditions of small temperature difference or small humidity difference; when the variable-capacity compressor 12 operates in the double-cylinder mode, the refrigerant flowing through the variable-capacity compressor 12 is independently compressed by each compression cylinder body, the refrigerants compressed by each compression cylinder body are not communicated with each other, and after each compression cylinder body completes compression, the compressed refrigerants are independently output to the refrigerant circulation pipeline.

Due to the variability of indoor and outdoor environmental factors, the working conditions of the air conditioner during operation are different, for example, in severe cold weather conditions in winter, the outdoor environment temperature is low, and the heat exchange quantity between the heat exchanger of the outdoor unit and the outdoor environment is directly influenced; or, in the two periods of daytime and night in summer, the outdoor environment temperature changes greatly, so that the compressor of the conventional air conditioner can not meet the refrigerant requirement under the current working condition when running in a single mode. Therefore, in order to meet the requirement of refrigerant under summer working conditions, the air conditioner of the present invention using the variable capacity compressor 12 provides a control method of the air conditioner in the embodiment (one) of the present invention, wherein the control method at least comprises the following steps: s110, controlling the air conditioner to perform refrigeration operation; s120, acquiring the outdoor environment temperature detected by the temperature sensor; s131, when the outdoor environment temperature is larger than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor.

The air conditioner adopts the variable-capacity compressor assembly, can control and change the operating frequency of the compressor, can change the refrigerant discharge capacity of the variable-capacity compressor 12 through mode switching, is suitable for working requirements under different working conditions, and can play a role in solving low-frequency vibration and improving the energy efficiency of the air conditioner.

In step S110, the air conditioner is started up in a cooling mode, and at this time, the variable capacity compressor of the air conditioner is started up to operate at a rated frequency under a rated working condition, in the embodiment, the rated working condition is that the outdoor ambient temperature is 35 ℃, and the rated frequency is an operating frequency corresponding to a case where the compressor can achieve the optimal operating efficiency when the outdoor ambient temperature is 35 ℃. Therefore, the outdoor ambient temperature at the rated operating condition can be used as the temperature threshold in the subsequent step.

When the actually acquired outdoor environment temperature is more than or equal to 35 ℃ of the rated working condition, the conventional single-cylinder compressor needs to operate at a higher operating frequency to meet the requirement of the refrigerant quantity, and the actual operating efficiency is lower than the optimal operating efficiency. When the actually acquired outdoor environment temperature is less than 35 ℃ of the rated working condition, and the running frequency of the conventional single-cylinder compressor is lower, the actual running efficiency is lower than the optimal running efficiency.

In the above-mentioned embodiment (a), the air conditioner operates in the cooling mode in summer, and the flow sequence of the refrigerant in the refrigerant circulation pipeline is as follows: the variable capacity compressor 12 → the outdoor heat exchanger 11 of the outdoor unit → the indoor heat exchanger 21 of the indoor unit → the variable capacity compressor 12, wherein the refrigerant releases heat to the outdoor environment in the outdoor heat exchanger 11 passing through the outdoor unit, and absorbs heat from the indoor environment in the indoor heat exchanger 21 passing through the indoor unit, thereby achieving the purpose of cooling the indoor environment.

In the summer refrigeration working condition, the outdoor environment temperature is detected by a first temperature sensor arranged in the outdoor unit in real time, and the first temperature sensor transmits the detected parameters such as the outdoor environment temperature to the controller, so that the controller can conveniently switch and adjust the operation mode of the variable-capacity compressor 12; in addition, the number of times of the control process executed by the controller under the refrigeration working condition in summer is one or more, so that when the controller executes the control process for the nth time, the first temperature sensor can transmit the real-time outdoor environment temperature matched with the current control process for the N times to the air conditioner, and the controller can conveniently perform adaptive adjustment on the variable capacity compressor 12 mode switched by the control process for the N-1 st time during the control process for the nth time, so that the operation mode of the variable capacity compressor 12 can be adapted to the current working conditions of different time points or time periods during the operation process of the air conditioner in a longer time period.

In step S131, the temperature threshold is a threshold parameter pre-stored in the controller, for example, the temperature threshold stored in the controller may be 30 ℃, 32 ℃, 35 ℃, and so on, that is, the temperature threshold is a temperature parameter with a high temperature in summer, which may affect the heat exchange between the outdoor heat exchanger 11 and the outdoor environment, and therefore, the temperature threshold is used as a critical condition for determining the operation mode of the variable displacement compressor 12.

Meanwhile, in step S131, when the outdoor ambient temperature is greater than or equal to the temperature threshold, it may be determined that the outdoor high temperature condition may limit the heat exchange amount of the outdoor heat exchanger 11, and thus the variable capacity compressor 12 needs to operate in a mode of outputting more refrigerants. For example, the temperature threshold set by the air conditioner is 32 ℃, after the air conditioner is started to perform cooling operation, the outdoor environment temperature detected by the first temperature sensor is 36 ℃, the judgment condition that the outdoor environment temperature is greater than or equal to the first temperature threshold is met, the controller controls the variable-capacity compressor 12 to operate in a two-cylinder mode, the two compression cylinders perform refrigerant compression operation independently, and twice the refrigerant quantity of a single compression cylinder is output to the refrigerant circulation pipeline, so that the refrigerant quantity flowing through the outdoor heat exchanger 11 is increased, and the heat exchange quantity between the air conditioner and the outdoor environment is improved.

Because the operation frequency of the variable capacity compressor 12 is high when the variable capacity compressor 12 operates in the two-cylinder mode, which easily causes the problem of refrigerant leakage inside the variable capacity compressor 12 and affects the refrigeration effect, in step S131, the controller controls the variable capacity compressor 12 to operate in the two-cylinder mode, and at the same time, the controller also controls to reduce the operation frequency of the variable capacity compressor 12, so as to reduce the compression ratio of the refrigerant, reduce the refrigerant leakage amount and improve the refrigeration effect.

In an embodiment of the present invention, when the variable displacement compressor 12 of the air conditioner operates in the two-cylinder mode, the controlling step of reducing the operating frequency of the variable displacement compressor 12 includes: s141, acquiring an indoor environment temperature and a target refrigerating temperature set by a user; s151, determining a temperature difference value between the indoor environment temperature and the target refrigerating temperature; s161, when the temperature difference value is larger than or equal to the preset temperature difference threshold value, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a first frequency modulation rate, otherwise, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

In an embodiment, the air conditioner has a second temperature sensor for detecting the indoor ambient temperature, and the second temperature sensor transmits the detected indoor ambient temperature and other parameters to the controller, so that the controller can adjust the operating frequency of the variable capacity compressor 12; in addition, the number of times of the control process executed by the controller under the refrigeration working condition in summer is one or more, so that when the controller executes the control process for the nth time, the second temperature sensor can transmit the real-time indoor environment temperature matched with the current control process for the N times to the air conditioner, and the controller can conveniently perform adaptive adjustment on the operation frequency of the variable capacity compressor 12 controlled by the control process for the N-1 st time during the control process for the nth time, so that the operation frequency of the variable capacity compressor 12 can be adapted to the current working conditions of different time points or time periods during the operation process of the air conditioner in a longer time period.

In step S151, the temperature difference between the indoor ambient temperature and the target cooling temperature is generally set to its absolute value in order to facilitate the comparison of the values in the subsequent determination step.

In step S161, the larger the temperature difference between the indoor ambient temperature and the target cooling temperature is, so in step S161, when the temperature difference is greater than or equal to the preset temperature difference threshold, the variable capacity compressor 12 is controlled to reduce the operating frequency thereof at the first frequency modulation rate with a larger value, and the frequency adjustment process of the variable capacity compressor 12 can be accelerated, the time length of frequency adjustment can be shortened, and the occurrence of the refrigerant leakage problem that may exist can be reduced without affecting the cooling effect of the air conditioner or with a lower impact.

In addition, in step S161, the smaller the temperature difference between the indoor ambient temperature and the target refrigeration temperature is, so in step S161, when the temperature difference is smaller than the preset temperature difference threshold, the variable capacity compressor 12 is controlled to reduce the operating frequency thereof at the second frequency modulation rate with a smaller value, so as to reduce the refrigerant leakage, prolong the variation duration of the refrigerant compression ratio, and avoid the problem that the refrigeration effect is affected due to the too fast variation of the temperature and pressure conditions of the refrigerant discharged by the variable capacity compressor 12; in addition, when the temperature difference value is greater than or equal to the preset temperature difference threshold value, the variable-capacity compressor 12 performs slow frequency regulation at the first frequency regulation rate, so that the operation time of the variable-capacity compressor 12 for compressing the refrigerant at a higher frequency is prolonged, the refrigerant flow with a higher compression ratio output by the variable-capacity compressor 12 can be increased, and the refrigeration effect is improved.

In step S161, the temperature difference threshold is also a threshold parameter pre-stored in the controller, for example, the temperature difference threshold stored in the controller may be 2 ℃, 3 ℃, 4 ℃, and so on.

In embodiment (one) of the present invention, the control method further includes the steps of: and S132, when the outdoor environment temperature is less than the temperature threshold, controlling the variable capacity compressor to operate in a two-stage mode, and increasing the operating frequency of the variable capacity compressor.

In step S132, when the outdoor ambient temperature is lower than the temperature threshold, it may be determined that the limitation of the outdoor high temperature condition on the heat exchange capacity of the outdoor heat exchanger 11 is small, and thus the variable displacement compressor 12 may be operated in a mode of outputting less refrigerant. For example, the temperature threshold set by the air conditioner is 32 ℃, after the air conditioner is started to perform cooling operation, the outdoor environment temperature detected by the first temperature sensor is 30 ℃, the judgment condition that the outdoor environment temperature is less than the first temperature threshold is met, the controller controls the variable-capacity compressor 12 to operate in a two-stage mode, and the two compression cylinder bodies sequentially perform refrigerant compression operation, so that the compression ratio of the air conditioner to the refrigerant is improved, the heat exchange amount of the refrigerant with unit flow rate is increased, and the heat exchange efficiency between the air conditioner and the outdoor environment is further improved.

Since the operation frequency of the variable capacity compressor 12 is low when the variable capacity compressor 12 operates in the two-stage mode, which tends to limit the compression efficiency of the variable capacity compressor 12 on the refrigerant and affect the refrigeration effect, in step S132, the controller controls the variable capacity compressor 12 to operate in the two-stage mode, and at the same time, controls the operation frequency of the variable capacity compressor 12 to increase the compression ratio of the refrigerant, thereby increasing the refrigeration effect.

In an embodiment of the present invention, when the variable displacement compressor 12 of the air conditioner is operated in the two-stage mode, the step of increasing the operation frequency of the variable displacement compressor 12 includes: s142, obtaining the indoor environment temperature and the target refrigerating temperature set by a user; s152, determining a temperature difference value between the indoor environment temperature and the target refrigerating temperature; s162, when the temperature difference value is larger than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to increase the operating frequency of the variable-capacity compressor at a first frequency modulation rate, otherwise, controlling the variable-capacity compressor to increase the operating frequency of the variable-capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

In the embodiment, the indoor ambient temperature obtained in step S142 is also the temperature parameter data detected by the second temperature sensor and transmitted to the controller as disclosed in the foregoing embodiments.

In step S162, the larger the temperature difference between the indoor ambient temperature and the target cooling temperature is, so in step S162, when the temperature difference is greater than or equal to the preset temperature difference threshold, the variable capacity compressor is controlled to increase the operating frequency thereof at the first frequency modulation rate with a larger value, the frequency adjustment process of the variable capacity compressor can be accelerated without affecting the cooling effect of the air conditioner or with a lower impact, the time length of the frequency adjustment is shortened, and thus the operating efficiency of the compressor is improved.

In addition, in step S162, the smaller the temperature difference between the indoor ambient temperature and the target cooling temperature is, so in step S162, when the temperature difference is smaller than the preset temperature difference threshold, the variable displacement compressor 12 is controlled to increase the operating frequency thereof at the second frequency modulation rate with a smaller value, thereby reducing the frequency fluctuation influence of the adjustment process of the variable displacement compressor 12, avoiding the excessively fast change of the temperature and pressure conditions of the refrigerant output by the variable displacement compressor 12, and improving the stability of the variable displacement compressor 12 in the frequency increasing process.

In step S162, the temperature difference threshold may employ the same threshold parameter as in step S161. Alternatively, the controller may store one or more threshold parameters for the variable displacement compressor 12 in a two-cylinder mode and a two-stage mode, respectively.

The following describes the specific working flow of the control method of the air conditioner in detail with reference to a specific embodiment:

s301, controlling the air conditioner to perform refrigeration operation;

s302, acquiring the outdoor environment temperature detected by the temperature sensor;

s303, acquiring an indoor environment temperature and a target refrigerating temperature set by a user, and determining a temperature difference value between the indoor environment temperature and the target refrigerating temperature;

s304, judging whether the outdoor environment temperature is greater than or equal to a preset temperature threshold, if so, executing a step S351, and if not, executing a step S352;

s351, controlling the variable-capacity compressor to run in a double-cylinder mode; acquiring a first frequency modulation rate and a second frequency modulation rate which are stored in advance, wherein the first frequency modulation rate is greater than the second frequency modulation rate, judging whether the temperature difference value between the indoor environment temperature and the target refrigeration temperature is greater than or equal to a preset temperature difference threshold value, if so, executing a step S361, and if not, executing a step S362;

s361, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a first frequency modulation rate;

s362, controlling the variable capacity compressor to reduce the running frequency of the variable capacity compressor at a second frequency modulation rate;

s352, controlling the variable capacity compressor to operate in a two-stage mode; acquiring a first frequency modulation rate and a second frequency modulation rate which are stored in advance, wherein the first frequency modulation rate is greater than the second frequency modulation rate, judging whether the temperature difference value between the indoor environment temperature and the target refrigeration temperature is greater than or equal to a preset temperature difference threshold value, if so, executing a step S363, and if not, executing a step S364;

s363, controlling the variable capacity compressor to increase the running frequency of the variable capacity compressor at a first frequency modulation rate;

and S364, controlling the variable capacity compressor to increase the running frequency of the variable capacity compressor at a second frequency modulation rate.

In the second embodiment of the present invention, the present invention further provides a control method of an air conditioner, the air conditioner has the same heat exchange functional components as those in the first embodiment, and in order to meet the heat exchange requirement of the winter working condition, the control method of the second embodiment at least includes the following steps: s210, controlling the heating operation of the air conditioner; s220, acquiring the outdoor environment temperature detected by the temperature sensor; and S231, controlling the variable-capacity compressor to operate in a double-cylinder mode when the outdoor environment temperature is less than or equal to the temperature threshold, and reducing the operating frequency of the variable-capacity compressor.

In step S210, the air conditioner is started up in a heating mode, and at this time, the variable capacity compressor of the air conditioner is started up to operate at a rated frequency under a rated working condition, in the embodiment, the rated working condition is that the outdoor ambient temperature is 2 ℃, and the rated frequency is an operating frequency corresponding to a case where the compressor can achieve the optimal operating efficiency when the outdoor ambient temperature is 2 ℃. Therefore, the outdoor ambient temperature at the rated operating condition can be used as the temperature threshold in the subsequent step.

When the actually obtained outdoor environment temperature is less than 2 ℃ of the rated working condition, the conventional single-cylinder compressor needs to operate at a higher operation frequency to meet the requirement of the refrigerant quantity, and the actual operation efficiency is lower than the optimal operation efficiency. When the actually acquired outdoor environment temperature is greater than or equal to 2 ℃ of the rated working condition, and the running frequency of the conventional single-cylinder compressor is lower, the actual running efficiency is lower than the optimal running efficiency.

In the second embodiment, the air conditioner operates in the heating mode in winter, and the flow sequence of the refrigerant in the refrigerant circulation pipeline is as follows: the variable capacity compressor 12 → the indoor heat exchanger 21 of the indoor unit → the outdoor heat exchanger 11 of the outdoor unit → the variable capacity compressor 12, wherein the refrigerant absorbs heat from the outdoor environment in the outdoor heat exchanger 11 of the outdoor unit, and releases heat to the indoor environment in the indoor heat exchanger 21 of the indoor unit, thereby achieving the purpose of heating and warming the indoor environment.

In the winter heating working condition, the outdoor environment temperature is detected by a first temperature sensor arranged on the outdoor unit in real time, and the first temperature sensor transmits the detected parameters such as the outdoor environment temperature to the controller, so that the controller can conveniently switch and adjust the operation mode of the variable-capacity compressor 12; in addition, the number of times of the control process executed by the controller under the heating working condition in summer is one or more, so that when the controller executes the control process for the nth time, the first temperature sensor can transmit the real-time outdoor environment temperature matched with the current control process for the N times to the air conditioner, and the controller can conveniently perform adaptive adjustment on the variable capacity compressor 12 mode switched by the control process for the N-1 st time during the control process for the nth time, so that the operation mode of the variable capacity compressor 12 can be adapted to the current working conditions of different time points or time periods during the operation process of the air conditioner in a longer time period.

In step S231, the temperature threshold is a threshold parameter pre-stored in the controller, for example, the temperature threshold stored in the controller may be-2 ℃, 0 ℃, 1 ℃ or the like, that is, the temperature threshold is a temperature parameter with a low temperature in winter that may affect the heat exchange between the outdoor heat exchanger 11 and the outdoor environment, and therefore, the temperature threshold is used as a critical condition for determining the operation mode of the variable displacement compressor 12.

Meanwhile, in step S231, when the outdoor ambient temperature is less than or equal to the temperature threshold, it may be determined that the outdoor low temperature condition may limit the heat exchange amount of the outdoor heat exchanger 11, and thus the variable capacity compressor 12 needs to operate in a mode of outputting more refrigerants. For example, the temperature threshold set by the air conditioner is 0 ℃, after the air conditioner is started to perform heating operation, the outdoor environment temperature detected by the first temperature sensor is-3 ℃, the judgment condition that the outdoor environment temperature is less than or equal to the first temperature threshold is met, the controller controls the variable-capacity compressor 12 to operate in a double-cylinder mode, the two compression cylinders perform refrigerant compression operation independently, and the refrigerant quantity which is twice as large as that of a single compression cylinder is output to the refrigerant circulation pipeline, so that the refrigerant quantity flowing through the outdoor heat exchanger 11 is increased, and the heat exchange quantity between the air conditioner and the outdoor environment is improved.

Since the operation frequency of the variable capacity compressor 12 is high when the variable capacity compressor 12 operates in the two-cylinder mode, which easily causes the problem of refrigerant leakage inside the variable capacity compressor 12 and affects the heating effect, in step S231, the controller controls the variable capacity compressor 12 to operate in the two-cylinder mode, and at the same time, controls to reduce the operation frequency of the variable capacity compressor 12, so as to reduce the refrigerant compression ratio, reduce the refrigerant leakage amount and improve the heating effect.

In an embodiment of the present invention, when the variable displacement compressor 12 of the air conditioner operates in the two-cylinder mode, the step of reducing the operating frequency of the variable displacement compressor 12 includes: s241, acquiring an indoor environment temperature and a target heating temperature set by a user; s251, determining a temperature difference value between the target heating temperature and the indoor environment temperature; s261, when the temperature difference value is larger than or equal to the preset temperature difference threshold value, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a first frequency modulation rate, otherwise, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

In an embodiment, the air conditioner has a second temperature sensor for detecting the indoor ambient temperature, and the second temperature sensor transmits the detected indoor ambient temperature and other parameters to the controller, so that the controller can adjust the operating frequency of the variable capacity compressor 12; in addition, the number of times of the control process executed by the controller under the heating working condition in winter is one or more, so that when the controller executes the control process for the nth time, the second temperature sensor can transmit the real-time indoor environment temperature matched with the current control process for the N times to the air conditioner, and the controller can conveniently and adaptively adjust the operating frequency of the variable capacity compressor 12 controlled by the control process for the N-1 st time during the control process for the nth time, so that the operating frequency of the variable capacity compressor 12 can be adapted to the current working conditions of different time points or time periods during the operation process of the air conditioner in a longer time period.

In step S251, the temperature difference between the target heating temperature and the indoor ambient temperature is generally an absolute value thereof, so as to facilitate the comparison of the values in the subsequent determination step.

In step S261, the larger the temperature difference between the target heating temperature and the indoor environment temperature is, so in step S261, when the temperature difference is greater than or equal to the preset temperature difference threshold, the variable capacity compressor 12 is controlled to reduce the operating frequency thereof at the first frequency modulation rate with a larger value, the frequency adjustment process of the variable capacity compressor 12 can be accelerated without affecting the heating effect of the air conditioner or with a lower impact, the time length of frequency adjustment is shortened, and the occurrence of the refrigerant leakage problem that may exist is reduced.

In addition, in step S261, the smaller the temperature difference between the target heating temperature and the indoor environment temperature is, so in step S261, when the temperature difference is smaller than the preset temperature difference threshold, the variable capacity compressor 12 is controlled to reduce the operating frequency thereof at the second frequency modulation rate with a smaller value, so as to reduce the refrigerant leakage, prolong the variation time of the refrigerant compression ratio, and avoid the problem that the heating effect is affected due to the too fast variation of the temperature and pressure conditions of the refrigerant discharged by the variable capacity compressor 12; in addition, when the temperature difference value is greater than or equal to the preset temperature difference threshold value, the variable-capacity compressor 12 performs slow frequency regulation at the first frequency regulation rate, so that the operation time of the variable-capacity compressor 12 for compressing the refrigerant at a higher frequency is prolonged, the refrigerant flow rate with a higher compression ratio output by the variable-capacity compressor 12 can be increased, and the heating effect is improved.

In step S261, the temperature difference threshold is also a threshold parameter pre-stored in the controller, for example, the temperature difference threshold stored in the controller may be 2 ℃, 3 ℃, 4 ℃, and so on.

In embodiment (two) of the present invention, the control method further includes the steps of: and S232, controlling the variable-capacity compressor to operate in a two-stage mode when the outdoor environment temperature is greater than the temperature threshold, and increasing the operating frequency of the variable-capacity compressor.

In step S232, when the outdoor ambient temperature is greater than the temperature threshold, it may be determined that the limitation of the outdoor high temperature condition on the heat exchange capacity of the outdoor heat exchanger 11 is small, and thus the variable displacement compressor 12 may be operated in a mode of outputting less refrigerant. For example, the temperature threshold set by the air conditioner is 0 ℃, after the air conditioner is started to perform heating operation, the outdoor environment temperature detected by the first temperature sensor is 4 ℃, the judgment condition that the outdoor environment temperature is greater than the first temperature threshold is met, the controller controls the variable-capacity compressor 12 to operate in a two-stage mode, and the two compression cylinder bodies sequentially perform refrigerant compression operation, so that the compression ratio of the air conditioner to the refrigerant is improved, the heat exchange amount of the refrigerant with unit flow is increased, and the heat exchange efficiency of the air conditioner and the outdoor environment is further improved.

Since the operation frequency of the variable capacity compressor 12 is low when the variable capacity compressor 12 operates in the two-stage mode, which tends to limit the compression efficiency of the variable capacity compressor 12 on the refrigerant and affect the heating effect, in step S232, the controller controls the variable capacity compressor 12 to operate in the two-stage mode, and at the same time, controls the operation frequency of the variable capacity compressor 12 to increase the compression ratio of the refrigerant and improve the heating effect.

In an embodiment of the present invention, when the variable displacement compressor 12 of the air conditioner operates in the two-stage mode, the step of increasing the operating frequency of the variable displacement compressor 12 controlled by the controller includes: s242, acquiring an indoor environment temperature and a target heating temperature set by a user; s252, determining a temperature difference value between the target heating temperature and the indoor environment temperature; s262, when the temperature difference value is larger than or equal to the preset temperature difference threshold value, controlling the variable-capacity compressor to increase the running frequency of the variable-capacity compressor at a first frequency modulation rate, otherwise, controlling the variable-capacity compressor to increase the running frequency of the variable-capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

In the embodiment, the indoor ambient temperature obtained in step S242 is also the temperature parameter data detected by the second temperature sensor and transmitted to the controller as disclosed in the foregoing embodiments.

In step S262, the larger the temperature difference between the target heating temperature and the indoor environment temperature is, so in step S262, when the temperature difference is greater than or equal to the preset temperature difference threshold, the variable capacity compressor 12 is controlled to increase the operating frequency thereof at the first frequency modulation rate with a larger value, the frequency adjustment process of the variable capacity compressor 12 can be accelerated without affecting the heating effect of the air conditioner or with a lower impact, the duration of the frequency adjustment is shortened, and thus the operating efficiency of the compressor is increased.

In addition, in step S262, the smaller the temperature difference between the target heating temperature and the indoor environment temperature is, so in step S262, when the temperature difference is smaller than the preset temperature difference threshold, the variable displacement compressor 12 is controlled to increase the operating frequency thereof at the second frequency modulation rate with a smaller value, thereby reducing the frequency fluctuation influence of the adjustment process of the variable displacement compressor 12, avoiding the too fast change of the temperature and pressure conditions of the refrigerant output by the variable displacement compressor 12, and improving the stability of the variable displacement compressor 12 in the frequency increasing process.

In step S262, the temperature difference threshold may employ the same threshold parameter as in step S261. Alternatively, the controller may store one or more threshold parameters for the variable displacement compressor 12 in a two-cylinder mode and a two-stage mode, respectively.

s401, controlling the heating operation of the air conditioner;

s402, acquiring the outdoor environment temperature detected by the temperature sensor;

s403, acquiring an indoor environment temperature and a target heating temperature set by a user, and determining a temperature difference value between the target heating temperature and the indoor environment temperature;

s404, judging whether the outdoor environment temperature is less than or equal to a preset temperature threshold, if so, executing a step S451, and if not, executing a step S452;

s451, controlling the variable-capacity compressor to run in a double-cylinder mode; acquiring a first frequency modulation rate and a second frequency modulation rate which are stored in advance, wherein the first frequency modulation rate is greater than the second frequency modulation rate, judging whether a temperature difference value between a target heating temperature and an indoor environment temperature is greater than or equal to a preset temperature difference threshold value, if so, executing a step S461, and if not, executing a step S462;

s461, controlling the variable capacity compressor to reduce the running frequency of the variable capacity compressor at a first frequency modulation rate;

s462, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a second frequency modulation rate;

s452, controlling the variable-capacity compressor to operate in a two-stage mode; acquiring a first frequency modulation rate and a second frequency modulation rate which are stored in advance, wherein the first frequency modulation rate is greater than the second frequency modulation rate, judging whether a temperature difference value between a target heating temperature and an indoor environment temperature is greater than or equal to a preset temperature difference threshold value, if so, executing a step S463, and if not, executing a step S464;

s463, controlling the variable capacity compressor to increase the running frequency of the variable capacity compressor at a first frequency modulation rate;

and S464, controlling the variable capacity compressor to increase the running frequency of the variable capacity compressor at a second frequency modulation rate.

In order to realize that the controller of the air conditioner in the embodiment (a) and the embodiment (b) can control the air conditioner to execute the above-mentioned process, the present invention further describes the components and structure of the specific components of the air conditioner:

the air conditioner comprises an indoor heat exchanger 21, an outdoor heat exchanger 11, a second four-way valve 14 and a throttling device 22, wherein the indoor heat exchanger 21, the outdoor heat exchanger 11, the second four-way valve 14, the throttling device 22 and the variable-capacity compression assembly in the embodiment are connected through a refrigerant pipeline to form a refrigerant circulating pipeline in the air conditioner, so that the circulation flow of the refrigerant between an indoor unit and an outdoor unit is realized.

The indoor heat exchanger 21 is used for exchanging heat with an indoor environment, and comprises a heat absorbing unit for absorbing heat of the indoor environment in a summer cooling working condition and a heat releasing unit for releasing heat to the indoor environment in a winter heating working condition; the outdoor heat exchanger 11 is used for exchanging heat in the outdoor environment, and includes transferring the indoor heat absorbed by the indoor heat exchanger 21 to the outdoor heat exchanger 11 through a refrigerant in the summer cooling condition, and discharging the heat to the outdoor environment through the outdoor heat exchanger 11, and absorbing the heat from the outdoor environment in the winter heating condition, and transferring the heat to the indoor heat exchanger 21 through the refrigerant, and discharging the heat to the indoor environment through the indoor heat exchanger 21.

In an embodiment, the air conditioner further includes a gas-liquid separator 16 connected to the refrigerant circulation pipeline, wherein the gas-liquid separator 16 is configured to separate a gaseous refrigerant flowing back to the variable capacity compressor 12 from a liquid refrigerant, and input the gaseous refrigerant to a suction port of the variable capacity compressor 12; in order to ensure that the two compression cylinders can independently suck the refrigerant in the dual-cylinder mode of operation, the gas-liquid separator 16 of the present invention includes a first outlet 161 and a second outlet 162 for respectively delivering the refrigerant to the two compression cylinders of the variable displacement compressor 12.

Alternatively, the gas-liquid separator 16 may be provided with only one refrigerant outlet, and the refrigerant outlet and the two compression cylinders of the variable capacity compressor 12 may be connected by a branch refrigerant pipeline, so that the refrigerant flowing out of the refrigerant outlet may flow into the corresponding compression cylinders along the branch refrigerant pipeline, respectively.

In the embodiment of the present invention, the variable displacement compressor assembly mainly includes a variable displacement compressor 12 and a first four-way valve 13, and the present invention realizes the switching of two operation modes of the variable displacement compressor 12 by switching between different valve positions of the first four-way valve 13.

In the specific embodiment, the variable displacement compressor 12 includes a first compression cylinder 121 and a second compression cylinder 122, both of which can independently perform compression operation on refrigerant, and in the illustration, as for a single unit of the variable displacement compressor 12, cylinder bodies of the two compression cylinders are not communicated with each other, in the present invention, the two compression cylinder bodies are communicated by the first four-way valve 13, and when the first four-way valve 13 is at different valve positions, the two compression cylinders respectively form a two-stage mode refrigerant flow path and a two-cylinder mode refrigerant flow path.

In an embodiment, the variable capacity compressor 12 has 5 ports, including a first port 123, a second port 124, a third port 125, a fourth port 126 and an exhaust port 127, disposed on the machine body, for communicating with an external refrigerant pipeline, where the fourth port 126 is communicated with the exhaust port 127 inside the machine body of the variable capacity compressor 12, and the exhaust port 127 is communicated with an exhaust pipeline of the compressor, so that a compressed refrigerant can be input into a refrigerant circulation pipeline of the air conditioner along the exhaust pipeline; the first compression cylinder 121 has a first inlet 1211 and a first outlet 1212, and the second compression cylinder 122 has a second inlet 1221 and a second outlet 1222, wherein the first inlet 1211 communicates with the first outlet 161 of the gas-liquid separator 16, and the second outlet 1222 of the second compression cylinder 122 communicates with the outlet 127 of the variable displacement compressor 12;

the first four-way valve 13 includes a valve body, a valve block disposed in a valve cavity in the valve body, and a first port 131, a second port 132, a third port 133, and a fourth port 134, the valve block having a first valve position for communicating the first port 131 with the second port 132 and communicating the third port 133 with the fourth port 134, and a second valve position for communicating the second port 132 with the third port 133 and blocking the first port 131 from the fourth port 134; the first port 131 is communicated with the second outlet 162 of the gas-liquid separator 16, the second port 132 is communicated with the second inlet 1221, the third port 133 is communicated with the first outlet 1212, and the fourth port 134 is communicated with the exhaust 127.

When the first four-way valve 13 is in the first valve position, the variable capacity compressor 12 operates in a two-cylinder mode, and the flow path of the refrigerant in the variable capacity compressor assembly includes two paths: (1) a refrigerant to be compressed flows in along the first port 123 of the variable displacement compressor 12, and sequentially flows through the first port 123 of the variable displacement compressor 12 → the first inlet 1211 → the first compression cylinder 121 → the first outlet 1212 → the second port 124 of the variable displacement compressor 12 → the third port 133 of the first four-way valve 13 → the valve chamber-the fourth port 134 of the first four-way valve 13 → the fourth port 126 of the variable displacement compressor 12 → the discharge port 127 of the variable displacement compressor 12, and in a refrigerant flow path, the refrigerant is compressed once by the first compression cylinder 121 and is finally output to a refrigerant circulation flow path of the air conditioner through the discharge port 127127; (2) the refrigerant to be compressed flows in along the first port of the first four-way valve 13, and sequentially flows through the first port 131 of the first four-way valve 13 → the valve chamber → the second port 132 of the first four-way valve 13 → the third port 125 of the variable displacement compressor 12 → the second inlet 1221 → the second compression cylinder 122 → the second outlet 1222 → the discharge port 127 of the variable displacement compressor 12, and in the refrigerant flow path, the refrigerant is primarily compressed by the second compression cylinder 122 and is finally discharged into the refrigerant circulation flow path of the air conditioner through the discharge port 127. In the two refrigerant flow paths, the two compression cylinders of the variable capacity compressor 12 can respectively and independently perform operations of air suction, compression, air exhaust and the like, so that the compression amount of the refrigerant can be effectively increased, and the refrigerant output quantity of the compressor is increased, so as to meet the refrigerant quantity requirement when a plurality of heat exchange units of the indoor unit perform operations such as refrigeration, heating or dehumidification.

When the first four-way valve 13 is in the second valve position, the variable capacity compressor 12 operates in a two-stage mode, and a flow path of the refrigerant in the variable capacity compressor 12 is one: the refrigerant to be compressed flows in along the first port 123 of the variable displacement compressor 12, and sequentially flows through the first port 123 of the variable displacement compressor 12 → the first inlet 1211 → the first compression cylinder 121 → the first outlet 1212 → the second port 124 of the variable displacement compressor 12 → the third port 133 of the first four-way valve 13 → the valve chamber → the second port 132 of the first four-way valve 13 → the third port 125 of the variable displacement compressor 12 → the second inlet 1221 → the second compression cylinder 122 → the second outlet 1222 of the second compression cylinder 122 → the discharge port 127 of the variable displacement compressor 12, and in this refrigerant flow path, the refrigerant is primarily compressed by the first compression cylinder 121, secondarily compressed by the second compression cylinder 122, and finally output to the refrigerant circulation flow path of the air conditioner via the discharge port 127. In the refrigerant flow path, the two compression cylinders of the variable capacity compressor 12 sequentially perform operations of air suction, compression, air discharge and the like, so that secondary compression of the refrigerant is realized, the compression ratio of the refrigerant can be effectively improved, and the heat exchange efficiency of the indoor heat exchanger 21 and the outdoor heat exchanger 11 is enhanced.

Therefore, the controller controls the variable displacement compressor 12 to operate in a two-cylinder mode, specifically, controls the valve block of the first four-way valve 13 to switch to the first valve position; when the variable displacement compressor 12 is controlled to operate in the two-stage mode, the valve block of the first four-way valve 13 is specifically controlled to switch to the second valve position.

In an embodiment of the present invention, the second four-way valve 14 is mainly used for controlling a flow direction of a refrigerant during a refrigeration cycle and a heating cycle, the second four-way valve 14 includes a valve body, a valve block disposed in a valve cavity in the valve body, and a first port 141, a second port 142, a third port 143, and a fourth port 144, the valve block has a first valve position communicating the first port 141 and the fourth port 144, communicating the second port 142 and the third port 143, and a second valve position communicating the first port 141 and the second port 142, communicating the third port 143 with the fourth port 144; the first port 141 is in communication with the outdoor heat exchanger 11, the second port 142 is in communication with the outlet of the gas-liquid separator 16, the third port 143 is in communication with the indoor heat exchanger 21, and the fourth port 144 is in communication with the exhaust port 127. When the air conditioner operates in a refrigerating mode, a valve block of the second four-way valve 14 is in a first valve position; during heating operation of the air conditioner, the valve block of the second four-way valve 14 is in the second valve position.

In order to implement the related flow of the control method disclosed in the embodiment (a), the controller of the air conditioner of the present invention is configured to: controlling the air conditioner to perform refrigeration operation; acquiring the outdoor environment temperature detected by a temperature sensor; and when the outdoor environment temperature is greater than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor.

In an embodiment, the controller is further configured to: acquiring indoor environment temperature and target refrigerating temperature set by a user; determining a temperature difference value between the indoor environment temperature and the target refrigerating temperature; when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a first frequency modulation rate; otherwise, controlling the variable capacity compressor to reduce the running frequency of the variable capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

In an embodiment, the controller is further configured to: and when the outdoor environment temperature is less than the temperature threshold value, controlling the variable capacity compressor to operate in a two-stage mode, and increasing the operating frequency of the variable capacity compressor.

In an embodiment, the controller is further configured to: acquiring indoor environment temperature and target refrigerating temperature set by a user; determining a temperature difference value between the indoor environment temperature and the target refrigerating temperature; when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to increase the running frequency of the variable-capacity compressor at a first frequency modulation rate; otherwise, controlling the variable capacity compressor to increase the running frequency of the variable capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

In order to implement the related flow of the control method disclosed in the embodiment (a), the controller of the air conditioner of the present invention is configured to: controlling the heating operation of the air conditioner; acquiring the outdoor environment temperature detected by a temperature sensor; and when the outdoor environment temperature is less than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor.

In an embodiment, the controller is further configured to: acquiring indoor environment temperature and target heating temperature set by a user; determining a temperature difference value between a target heating temperature and an indoor environment temperature; when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a first frequency modulation rate; otherwise, controlling the variable capacity compressor to reduce the running frequency of the variable capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

In an embodiment, the controller is further configured to: and when the outdoor environment temperature is greater than the temperature threshold value, controlling the variable capacity compressor to operate in a two-stage mode, and increasing the operating frequency of the variable capacity compressor.

In an embodiment, the controller is further configured to: acquiring indoor environment temperature and target heating temperature set by a user; determining a temperature difference value between a target heating temperature and an indoor environment temperature; when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to increase the running frequency of the variable-capacity compressor at a first frequency modulation rate; otherwise, controlling the variable capacity compressor to increase the running frequency of the variable capacity compressor at a second frequency modulation rate; the first frequency modulation rate is greater than the second frequency modulation rate.

It is to be understood that the present invention is not limited to the procedures and structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims

1. A control method of an air conditioner, characterized in that the control method comprises:

controlling the air conditioner to perform refrigeration operation;

acquiring the outdoor environment temperature detected by a temperature sensor;

when the outdoor environment temperature is greater than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor;

and when the outdoor environment temperature is less than the temperature threshold value, controlling the variable-capacity compressor to operate in a two-stage mode, and increasing the operating frequency of the variable-capacity compressor.

2. The control method according to claim 1, characterized by further comprising:

acquiring indoor environment temperature and target refrigerating temperature set by a user;

determining a temperature difference value between the indoor environment temperature and the target refrigeration temperature;

when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to reduce the running frequency of the variable-capacity compressor at a first frequency modulation rate;

otherwise, controlling the variable capacity compressor to reduce the running frequency of the variable capacity compressor at a second frequency modulation rate;

the first frequency modulation rate is greater than the second frequency modulation rate.

3. The control method according to claim 1,

the control method further comprises the following steps:

when the temperature difference value is greater than or equal to a preset temperature difference threshold value, controlling the variable-capacity compressor to increase the running frequency of the variable-capacity compressor at a first frequency modulation rate;

otherwise, controlling the variable capacity compressor to increase the running frequency of the variable capacity compressor at a second frequency modulation rate;

4. An air conditioner is characterized by comprising a controller, a first temperature sensor and a variable-capacity compressor assembly, wherein the first temperature sensor is used for detecting the temperature of an outdoor environment, the variable-capacity compressor assembly is used for driving a refrigerant to circulate, the variable-capacity compressor assembly comprises a variable-capacity compressor (12), and the operation modes of the variable-capacity compressor (12) comprise a two-stage mode and a two-cylinder mode; the controller is configured to:

controlling the air conditioner to perform refrigeration operation;

acquiring the outdoor environment temperature detected by the temperature sensor;

when the outdoor environment temperature is greater than or equal to a temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor;

5. The air conditioner according to claim 4,

the variable capacity compressor assembly comprises the variable capacity compressor (12) and a first four-way valve (13);

the air conditioner comprises an indoor heat exchanger (21), an outdoor heat exchanger (11), a second four-way valve (14) and a throttling device (22);

the variable-capacity compressor assembly is connected with the indoor heat exchanger (21), the outdoor heat exchanger (11), the second four-way valve (14) and the throttling device (22) through refrigerant pipelines to form a refrigerant circulating pipeline.

6. The air conditioner according to claim 5,

the air conditioner also comprises a gas-liquid separator (16) connected to the refrigerant circulating pipeline, wherein the gas-liquid separator (16) comprises a first outlet (161) and a second outlet (162);

the variable capacity compressor (12) comprising a first compression cylinder (121) and a second compression cylinder (122), the first compression cylinder (121) having a first gas inlet (1211) and a first gas outlet (1212), the second compression cylinder (122) having a second gas inlet (1221) and a second gas outlet (1222), wherein the first gas inlet (1211) communicates with the first outlet (161) of the gas-liquid separator (16), and the second gas outlet (1222) of the second compression cylinder (122) communicates with a gas outlet (127) of the variable capacity compressor (12);

the first four-way valve (13) comprises a valve body, a valve block arranged in a valve cavity in the valve body, a first interface (131), a second interface (132), a third interface (133) and a fourth interface (134), wherein the valve block is provided with a first valve position for communicating the first interface (131) with the second interface (132) and communicating the third interface (133) with the fourth interface (134), a second valve position for communicating the second interface (132) with the third interface (133) and blocking the first interface (131) from the fourth interface (134); wherein the first port (131) is in communication with the second outlet (162) of the gas-liquid separator (16), the second port (132) is in communication with the second gas inlet (1221), the third port (133) is in communication with the first gas outlet (1212), and the fourth port (134) is in communication with the gas outlet (127);

said controlling said variable capacity compressor (12) to operate in a two-cylinder mode comprising: controlling a valve block of the first four-way valve (13) to switch to the first valve position;

said controlling said variable capacity compressor (12) to operate in a two-stage mode comprising: and a valve block for controlling the first four-way valve (13) is switched to the second valve position.

7. The air conditioner according to claim 6,

the gas-liquid separator (16) comprises an inlet;

the second four-way valve (14) comprises a valve body, a valve block arranged in a valve cavity in the valve body, a first interface (141), a second interface (142), a third interface (143) and a fourth interface (144), wherein the valve block is provided with a first valve position communicated with the first interface (141) and the fourth interface (144) and the second interface (142) and the third interface (143), and a second valve position communicated with the first interface (141) and the second interface (142) and the third interface (143) and the fourth interface (144); wherein the first port (141) communicates with the outdoor heat exchanger (11), the second port (142) communicates with the outlet of the gas-liquid separator (16), the third port (143) communicates with the indoor heat exchanger (21), and the fourth port (144) communicates with the discharge port (127);

when the air conditioner operates in a refrigerating mode, the valve block of the second four-way valve (14) is in a first valve position.

8. A control method of an air conditioner, characterized in that the control method comprises:

controlling the heating operation of the air conditioner;

acquiring the outdoor environment temperature detected by a temperature sensor;

when the outdoor environment temperature is less than or equal to the temperature threshold value, controlling the variable-capacity compressor to operate in a double-cylinder mode, and reducing the operating frequency of the variable-capacity compressor;

and when the outdoor environment temperature is greater than the temperature threshold value, controlling the variable-capacity compressor to operate in a two-stage mode, and increasing the operating frequency of the variable-capacity compressor.

9. The control method according to claim 8, characterized by further comprising:

acquiring indoor environment temperature and target heating temperature set by a user;

determining a temperature difference value between the target heating temperature and the indoor environment temperature;

10. The control method according to claim 8, characterized by further comprising:

11. An air conditioner is characterized by comprising a controller, a first temperature sensor and a variable-capacity compressor assembly, wherein the first temperature sensor is used for detecting the temperature of an outdoor environment, the variable-capacity compressor assembly is used for driving a refrigerant to circulate, the variable-capacity compressor assembly comprises a variable-capacity compressor (12), and the operation modes of the variable-capacity compressor (12) comprise a two-stage mode and a two-cylinder mode; the controller is configured to:

controlling the heating operation of the air conditioner;

12. The air conditioner according to claim 11,

the variable-capacity compressor assembly is connected with the indoor heat exchanger (21), the outdoor heat exchanger (11), the second four-way valve (14) and the throttling device through refrigerant pipelines to form a refrigerant circulating pipeline.

13. The air conditioner according to claim 12,

14. The air conditioner according to claim 13,

the gas-liquid separator (16) comprises an inlet;

when the air conditioner is in heating operation, the valve block of the second four-way valve (14) is in a second valve position.