Air conditioning system, pressure sensing method and apparatus therefor, and storage medium

Abstract

Disclosed are an air conditioning system, a pressure sensing method and apparatus therefor, and a storage medium. The method comprises: when an air conditioning system is in a cooling mode, acquiring system evaporating pressure sensed by a pressure sensor and used for controlling a compressor, and determining, according to the system evaporating pressure and a compressor characteristic parameter, system condensing pressure used for controlling an outdoor fan; when the air conditioning system is in a heating mode, acquiring system condensing pressure sensed by the pressure sensor and used for controlling the compressor, and determining, according to the system condensing pressure and the compressor characteristic parameter, system evaporating pressure used for controlling the outdoor fan. Monitoring pressure with a single pressure sensor, and sensing system evaporating pressure in a cooling mode and sensing system condensing pressure in a heating mode allows for fuzzy control requirements of a fan to be met, even if the system condensing pressure in the cooling mode and the system evaporating pressure in the heating mode are calculated from a compressor characteristic parameter, thereby reducing costs.

Description

Air conditioning systems and their pressure detection methods, devices and storage media

[0001] This application claims priority to Chinese Patent Application No. 202411434828.8, filed on October 14, 2024, entitled "Air Conditioning System and Pressure Detection Method, Apparatus and Storage Medium Thereof", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to the field of air conditioning technology, specifically to an air conditioning system and its pressure detection method, device, and storage medium. Background Technology

[0003] In a multi-split air conditioning system, at least two pressure sensors are required: one installed on the compressor's suction line to detect the system evaporating pressure, and one installed on the compressor's discharge line to detect the system condensing pressure. In cooling mode, the compressor frequency is controlled based on the detected system evaporating pressure, and the fan speed is controlled based on the detected system condensing pressure. In heating mode, the compressor frequency is controlled based on the detected system condensing pressure, and the fan speed is controlled based on the detected system evaporating pressure.

[0004] However, fan control typically employs fuzzy control, which does not require precise control of the system condensing or evaporating pressure. Therefore, in practical applications, it is not always necessary to have two pressure sensors to monitor the relevant pressure values. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of the prior art by providing an air conditioning system and its pressure detection method, device, and storage medium, which is achieved through the following technical solutions.

[0006] A first aspect of the present invention provides a pressure detection method, the method comprising:

[0007] When the air conditioning system is in cooling mode, the system evaporation pressure detected by the pressure sensor for controlling the compressor is obtained, and the system condensation pressure for controlling the outdoor fan is determined based on the detected system evaporation pressure and compressor characteristic parameters.

[0008] When the air conditioning system is in heating mode, the system condensing pressure detected by the pressure sensor for controlling the compressor is acquired, and the system evaporating pressure for controlling the outdoor fan is determined based on the detected system condensing pressure and the compressor characteristic parameters.

[0009] In some embodiments of this application, determining the system condensing pressure for controlling the outdoor fan based on the detected system evaporating pressure and compressor characteristic parameters includes:

[0010] The virtual condensing pressure is calculated using the system evaporation pressure and the compressor characteristic parameters; the compressor characteristic parameters include at least one of the compressor input power, compressor discharge temperature, and compressor suction temperature.

[0011] The degree of frequency change of the compressor is determined based on two consecutive detected compressor operating frequencies;

[0012] The system condensing pressure is determined based on the virtual condensing pressure and the degree of frequency change.

[0013] In some embodiments of this application, calculating the virtual condensing pressure using the system evaporation pressure and the compressor characteristic parameters includes:

[0014] Obtain the saturation temperature corresponding to the evaporation pressure of the system;

[0015] The virtual condensing pressure is calculated based on the saturation temperature, the compressor characteristic parameters, and a preset first fitting formula; the first fitting formula is used to calculate the virtual condensing pressure of the air conditioning system in cooling mode.

[0016] In some embodiments of this application, determining the system condensing pressure based on the virtual condensing pressure and the degree of frequency variation includes:

[0017] When the frequency change is less than a preset threshold, the system condensing pressure is determined using the internal and outlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual condensing pressure.

[0018] If the frequency change is greater than or equal to a preset threshold, the virtual condensing pressure is used as the system condensing pressure.

[0019] In some embodiments of this application, determining the system condensing pressure using the internal and outlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual condensing pressure includes:

[0020] The saturation temperature of the system condensation pressure is calculated based on the internal and outlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual condensation pressure.

[0021] The system condensing pressure is obtained based on the saturation temperature of the system condensing pressure.

[0022] In some embodiments of this application, determining the system evaporation pressure for controlling the outdoor fan based on the detected system condensing pressure and compressor characteristic parameters includes:

[0023] The virtual evaporation pressure is calculated using the system condensing pressure and the compressor characteristic parameters; the compressor characteristic parameters include at least one of the compressor input power, compressor discharge temperature, and compressor suction temperature.

[0024] The degree of frequency change of the compressor is determined based on two consecutive detected compressor operating frequencies;

[0025] The system evaporation pressure is determined based on the virtual evaporation pressure and the degree of frequency change.

[0026] In some embodiments of this application, calculating the virtual evaporation pressure using the system condensing pressure and the compressor characteristic parameters includes:

[0027] Obtain the saturation temperature corresponding to the condensation pressure of the system;

[0028] The virtual evaporation pressure is calculated based on the saturation temperature, the compressor characteristic parameters, and a preset second fitting formula; the second fitting formula is used to calculate the virtual evaporation pressure of the air conditioning system in heating mode.

[0029] In some embodiments of this application, determining the system evaporation pressure based on the virtual evaporation pressure and the degree of frequency change includes:

[0030] When the frequency change is less than a preset threshold, the system evaporation pressure is determined using the internal temperature and inlet temperature of the outdoor heat exchanger and the saturation temperature corresponding to the virtual evaporation pressure.

[0031] If the frequency change is greater than or equal to a preset threshold, the virtual evaporation pressure is taken as the system evaporation pressure.

[0032] In some embodiments of this application, determining the system evaporation pressure using the internal temperature and inlet temperature of the outdoor heat exchanger and the saturation temperature corresponding to the virtual evaporation pressure includes:

[0033] The saturation temperature of the system evaporation pressure is calculated based on the internal temperature and inlet temperature of the outdoor heat exchanger and the saturation temperature corresponding to the virtual evaporation pressure.

[0034] The system evaporation pressure is obtained based on the saturation temperature of the system evaporation pressure.

[0035] A second aspect of the present invention provides a pressure detection device for an air conditioning system, the device comprising:

[0036] The refrigeration detection module is used to acquire the system evaporation pressure detected by the pressure sensor for controlling the compressor when the air conditioning system is in refrigeration mode, and to determine the system condensation pressure for controlling the outdoor fan based on the detected system evaporation pressure and compressor characteristic parameters.

[0037] The heating detection module is used to acquire the system condensing pressure detected by the pressure sensor for controlling the compressor when the air conditioning system is in heating mode, and to determine the system evaporating pressure for controlling the outdoor fan based on the detected system condensing pressure and compressor characteristic parameters.

[0038] A third aspect of the present invention provides an air conditioning system, including a compressor, an indoor unit and a four-way valve, and further including a pressure detection device for the air conditioning system as described in the second aspect;

[0039] A pressure sensor is installed on the connecting pipe between the first end of the four-way valve and one end of the indoor unit. The pressure sensor is used to detect the system evaporation pressure for controlling the compressor when the air conditioning system is in cooling mode, and to detect the system condensation pressure for controlling the compressor when the air conditioning system is in heating mode.

[0040] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, performs the steps of the method described in the first aspect above.

[0041] Based on the air conditioning system and its pressure detection method, device and storage medium described above, the technical solution of the present invention has the following beneficial effects or advantages:

[0042] By installing a pressure sensor between the four-way valve and the indoor unit, in cooling mode, the pressure sensor detects the system evaporating pressure and calculates the system condensing pressure based on the evaporating pressure and compressor characteristic parameters to control the outdoor fan. In heating mode, the pressure sensor detects the system condensing pressure and calculates the system evaporating pressure based on the condensing pressure and compressor characteristic parameters to control the outdoor fan. Therefore, even though the system condensing pressure in cooling mode and the system evaporating pressure in heating mode are calculated from compressor characteristic parameters rather than using precise values ​​detected by the pressure sensor, fuzzy control of the fan is still possible. This allows the air conditioning system to achieve compressor frequency control and fan speed control using only one pressure sensor, reducing costs. Attached Figure Description

[0043] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0044] Figure 1 is a schematic diagram of an air conditioning system according to the present invention;

[0045] Figure 2 is a schematic diagram of refrigerant circulation in the cooling mode of an air conditioning system according to the present invention;

[0046] Figure 3 is a schematic diagram of refrigerant circulation in the heating mode of an air conditioning system according to the present invention;

[0047] Figure 4 is a schematic flowchart of an embodiment of a pressure detection method for an air conditioning system according to an exemplary embodiment of the present invention;

[0048] Figure 5 is a schematic diagram of a pressure detection device according to an exemplary embodiment of the present invention;

[0049] Figure 6 is a schematic diagram of the structure of a storage medium according to an exemplary embodiment of the present invention.

[0050] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0052] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0053] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0054] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0055] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0056] Controlling the compressor frequency and fan speed based on evaporation and condensation pressures is a common control method in current multi-split air conditioning systems. In cooling mode, the compressor operating frequency is typically controlled based on the deviation between the actual and target evaporation pressures, while the fan speed is controlled based on the deviation between the actual and target condensation pressures. In heating mode, the compressor operating frequency is typically controlled based on the deviation between the actual and target condensation pressures, while the fan speed is controlled based on the deviation between the actual and target evaporation pressures. Therefore, a pressure sensor needs to be installed on both the compressor's discharge and suction pipes to detect the actual evaporation and condensation pressures of the air conditioning system.

[0057] Since controlling the operating frequency of the compressor directly affects the user's comfort experience, it is more accurate to use a pressure sensor to detect the pressure value used to control the compressor (including the evaporating pressure in cooling mode and the condensing pressure in heating mode). However, fan control usually adopts fuzzy control and does not require very precise control of the system condensing pressure or system evaporating pressure. Therefore, it is not necessary to use a pressure sensor to monitor the relevant pressure values.

[0058] Based on this, this application proposes an air conditioning system that uses only one pressure sensor for pressure monitoring. In cooling mode, the pressure sensor detects the system evaporation pressure and calculates the system condensation pressure using compressor characteristic parameters and the system evaporation pressure. In heating mode, the pressure sensor detects the system condensation pressure and calculates the system evaporation pressure using compressor characteristic parameters and the system condensation pressure.

[0059] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0060] Referring to Figure 1, the air conditioning system includes an outdoor unit 10 and an indoor unit 20 connected to the outdoor unit. The outdoor unit 10 includes a compressor 101, an oil separator 102, a gas-liquid separator 103, a four-way valve 104, a pressure sensor 105, an outdoor heat exchanger 106, and an outdoor fan 107; the indoor unit 20 includes an indoor heat exchanger 201.

[0061] In this embodiment, the compressor 101 includes an intake end and an exhaust end. The intake end of the compressor 101 is connected to the gas-liquid separator 103, and the exhaust end of the compressor 101 is connected to the oil-liquid separator 102.

[0062] In this embodiment, the oil separator 102 is disposed between the compressor 101 and the four-way valve 104. The oil separator 102 includes an inlet, an outlet, and an oil outlet. The inlet of the oil separator 102 is connected to the exhaust end of the compressor 101, the outlet of the oil separator 102 is connected to the four-way valve 104, and the oil outlet of the oil separator 102 is connected to the suction end of the compressor 101.

[0063] In this embodiment, the gas-liquid separator 103 is disposed between the compressor 101 and the four-way valve 104. The gas-liquid separator 103 includes an inlet and an outlet. The inlet of the gas-liquid separator 103 is connected to the four-way valve 104, and the outlet of the gas-liquid separator 103 is connected to the suction end of the compressor 101.

[0064] In this embodiment, when the air conditioning system is in cooling mode, the four-way valve 104 connects the discharge end of the compressor 101 to one end of the outdoor heat exchanger 106 and one end of the indoor heat exchanger 201 to the suction end of the compressor 101. When the air conditioning system is in heating mode, the four-way valve 104 switches to connect the discharge end of the compressor 101 to one end of the indoor heat exchanger 201 and one end of the outdoor heat exchanger 106 to the suction end of the compressor 101. The other end of the outdoor heat exchanger 106 is connected to the other end of the indoor heat exchanger 201.

[0065] Furthermore, the four-way valve 104 includes a first port a, a second port b, a third port c, and a fourth port d. The first port a is connected to one end of the indoor heat exchanger 201, the second port b is connected to the suction end of the compressor 101, the third port c is connected to one end of the outdoor heat exchanger 106, and the fourth port d is connected to the discharge end of the compressor 101. When the air conditioning system is in cooling mode, the first port a and the second port b, and the third port c and the fourth port d are connected within the four-way valve 104. When the air conditioning system is in heating mode, the first port a and the fourth port d, and the second port b and the third port c are connected within the four-way valve 104.

[0066] In this embodiment, the pressure sensor 105 is installed on the connecting pipe between the four-way valve 104 and one end of the indoor heat exchanger 201. The pressure sensor 105 is used to detect the system evaporation pressure of the air conditioning system, i.e., the low pressure value, when the air conditioning system is in the cooling mode, and to detect the system condensation pressure of the air conditioning system, i.e., the high pressure value, when the air conditioning system is in the heating mode.

[0067] Referring to Figure 2, when the air conditioning system is in cooling mode, the first port a and the second port b of the four-way valve 104 are connected, and the third port c and the fourth port d are connected. The four-way valve 104 is used to connect the exhaust end of the compressor 101 and one end of the outdoor heat exchanger 106, as well as one end of the indoor heat exchanger 201 and the suction end of the compressor 101.

[0068] In other words, when the air conditioning system is in cooling mode, the refrigerant starts from the suction end of the compressor 101, passes sequentially through the oil separator 102, the fourth port d of the four-way valve 104, the third port c of the four-way valve 104, the outdoor heat exchanger 106, the indoor heat exchanger 201, the first port a of the four-way valve 104, the second port b of the four-way valve 104, and the gas-liquid separator 103, and finally flows back to the compressor 101. In this operating mode, the pressure sensor 105 is used to detect the system evaporation pressure, that is, it acts as a low-pressure sensor to detect the low-pressure value of the air conditioning system.

[0069] Referring to Figure 3, when the air conditioning system is in heating mode, the first port a and the fourth port d of the four-way valve 104 are connected, and the second port b and the third port c are connected. The four-way valve 104 is used to connect the exhaust end of the compressor 101 and one end of the indoor heat exchanger 201, as well as one end of the outdoor heat exchanger 106 and the suction end of the compressor 101.

[0070] In other words, when the air conditioning system is in heating mode, the refrigerant starts from the suction end of the compressor 101, flows sequentially through the oil separator 102, the fourth port d of the four-way valve 104, the first port a of the four-way valve 7, the indoor heat exchanger 201, the outdoor heat exchanger 106, the third port c of the four-way valve 104, the second port b of the four-way valve 104, and the gas-liquid separator 103, and finally flows back to the compressor 101. In this operating mode, the pressure sensor 105 is used to detect the system condensing pressure, that is, it acts as a high-pressure sensor to detect the high-pressure value of the air conditioning system.

[0071] In this embodiment, the air conditioning system also includes a pressure detection device (not shown in Figure 1). This pressure detection device is electrically connected to the pressure sensor 105, the compressor 101, and the outdoor fan 107. When the air conditioning system is in cooling mode, the pressure detection device acquires the system evaporation pressure detected by the pressure sensor 105 to accurately control the operating frequency of the compressor 101, and determines the system condensing pressure based on the system evaporation pressure and compressor characteristic parameters to control the speed of the outdoor fan 107. When the air conditioning system is in heating mode, the device acquires the system condensing pressure detected by the pressure sensor 105 to accurately control the operating frequency of the compressor 101, and determines the system evaporation pressure based on the system condensing pressure and compressor characteristic parameters to control the speed of the outdoor fan 107.

[0072] The technical effects that can be achieved based on the above description are:

[0073] By using only one pressure sensor for pressure monitoring, the system evaporation pressure is detected in cooling mode and the system condensation pressure is detected in heating mode. Even though the system condensation pressure in cooling mode and the system evaporation pressure in heating mode are calculated from the compressor characteristic parameters rather than the precise values ​​detected by the pressure sensor, the fuzzy control method of the fan can still be satisfied. In this way, the air conditioning system can achieve compressor frequency control and fan speed control with only one pressure sensor, thus reducing costs.

[0074] In some embodiments, the air conditioning system may further include electronic components for detecting the input voltage and input current of the compressor 101, through which the input power of the compressor 101 can be obtained.

[0075] In addition, the air conditioning system may also include a temperature sensor for detecting the exhaust temperature of the compressor 101 and a temperature sensor for detecting the intake temperature of the compressor 101, wherein the temperature sensor for detecting the exhaust temperature is located on the exhaust pipe of the compressor 101 and the temperature sensor for detecting the intake temperature is located on the intake pipe of the compressor 101.

[0076] Furthermore, the input power, suction temperature, and discharge temperature of compressor 101 can all be regarded as compressor characteristic parameters, and can be used in the calculation of system condensing pressure in cooling mode and system evaporating pressure in heating mode.

[0077] In some embodiments, temperature sensors may be installed at the inlet, the interior, and the outlet of the outdoor heat exchanger 106. These temperature sensors are used to detect the inlet temperature, the interior temperature, and the outlet temperature of the outdoor heat exchanger 106, respectively.

[0078] Figure 4 is a schematic flowchart illustrating an embodiment of a pressure detection method for an air conditioning system according to an exemplary embodiment of the present invention. The structure of the air conditioning system is shown in the embodiments shown in Figures 1-3 above. As shown in Figure 4, the pressure detection method includes the following steps:

[0079] Step 401: When the air conditioning system is in cooling mode, obtain the system evaporating pressure detected by the pressure sensor to control the compressor, and determine the system condensing pressure to control the outdoor fan based on the detected system evaporating pressure and compressor characteristic parameters.

[0080] Step 402: When the air conditioning system is in heating mode, obtain the system condensing pressure detected by the pressure sensor for controlling the compressor, and determine the system evaporating pressure for controlling the outdoor fan based on the detected system condensing pressure and compressor characteristic parameters.

[0081] In cooling mode, the outdoor heat exchanger of the air conditioning system is used as a condenser, and the indoor heat exchanger is used as an evaporator. The system evaporation pressure detected by the pressure sensor can be understood as the compressor suction pressure, i.e., the low pressure value.

[0082] For example, the system evaporation pressure in cooling mode can be used to control the operating frequency of the compressor.

[0083] The system condensing pressure obtained from the system evaporation pressure and compressor characteristic parameters can be understood as the compressor discharge pressure, i.e., the high pressure value.

[0084] For example, the system condensing pressure in cooling mode can be used to control the speed of the outdoor fan.

[0085] Considering that the system condensing pressure in cooling mode is not a precise value detected by a pressure sensor, fuzzy control can be used to control the outdoor fan speed based on the system condensing pressure. For example, the target condensing pressure input to the system can be divided into multiple fuzzy subsets, such as "low," "medium," and "high." The currently used target condensing pressure belongs to the medium fuzzy subset. The system condensing pressure is compared with the medium fuzzy subset. If the system condensing pressure is lower than the medium fuzzy subset, the outdoor fan speed is reduced; if the system condensing pressure is higher than the medium fuzzy subset, the outdoor fan speed is increased.

[0086] In heating mode, the outdoor heat exchanger of the air conditioning system is used as an evaporator, and the indoor heat exchanger is used as a condenser. The system condensing pressure detected by the pressure sensor can be understood as the compressor discharge pressure, i.e., the high pressure value.

[0087] For example, the system condensing pressure in heating mode can be used to control the operating frequency of the compressor.

[0088] The system evaporation pressure obtained from the system condensing pressure and compressor characteristic parameters can be understood as the compressor suction pressure, i.e., the low pressure value.

[0089] For example, the system evaporation pressure in heating mode can be used to control the speed of the outdoor fan.

[0090] Considering that the system evaporation pressure in heating mode is not a precise value detected by a pressure sensor, fuzzy control can be used to control the outdoor fan speed based on the system evaporation pressure. For example, the target evaporation pressure input to the system can be divided into multiple fuzzy subsets, such as "low," "medium," and "high." The currently used target evaporation pressure belongs to the medium fuzzy subset. The system evaporation pressure is compared with the medium fuzzy subset. If the system evaporation pressure is lower than the medium fuzzy subset, the outdoor fan speed is reduced; if the system evaporation pressure is higher than the medium fuzzy subset, the outdoor fan speed is increased.

[0091] Compressor characteristic parameters can be understood as system parameters related to the compressor in an air conditioning system, which can reflect the pressure of the refrigerant circulating in the pipeline.

[0092] For example, compressor characteristic parameters may include at least one of the compressor's input power, compressor's discharge temperature, and compressor's suction temperature.

[0093] It is worth noting that steps 401 and 402 above are pressure detection procedures under two different operating modes of the air conditioning system. Therefore, there is no restriction on the order of steps 401 and 402.

[0094] Thus, the pressure detection process shown in Figure 4 is completed. By using only one pressure sensor for pressure monitoring, the system evaporation pressure is detected in cooling mode and the system condensation pressure is detected in heating mode. In this way, even though the system condensation pressure in cooling mode and the system evaporation pressure in heating mode are calculated from the compressor characteristic parameters rather than the precise values ​​detected by the pressure sensor, the fuzzy control method of the fan can still be satisfied. In this way, the air conditioning system can achieve compressor frequency control and fan speed control using only one pressure sensor, thereby reducing costs.

[0095] In some embodiments of this application, step 401 above, which determines the system condensing pressure for controlling the outdoor fan based on the detected system evaporating pressure and compressor characteristic parameters, includes:

[0096] The virtual condensing pressure is calculated using the system evaporation pressure and compressor characteristic parameters, which include at least one of the following: input power, compressor discharge temperature, and compressor suction temperature.

[0097] The degree of frequency change of the compressor is determined based on the compressor operating frequency detected twice consecutively;

[0098] The system condensing pressure is determined based on the virtual condensing pressure and the degree of frequency variation.

[0099] Virtual condensing pressure can be understood as the theoretical compressor discharge pressure determined by the characteristics of the compressor.

[0100] The compressor operating frequency refers to the actual frequency of the compressor. In refrigeration mode, this frequency changes dynamically as the deviation between the system evaporating pressure and the target evaporating pressure changes.

[0101] The degree of frequency change can be understood as the rate of change of the compressor's operating frequency between two consecutive measurements. For example, if the compressor's operating frequency is measured every minute, the difference between the two measured frequencies is divided by the previously measured frequency to obtain the degree of frequency change.

[0102] In this embodiment, a theoretical virtual condensing pressure is calculated using the system evaporation pressure and compressor characteristic parameters. Then, the final system condensing pressure is obtained by combining the compressor frequency variation and the virtual condensing pressure, thereby improving the accuracy of the system condensing pressure.

[0103] In some embodiments of this application, the process of calculating the virtual condensing pressure using system evaporating pressure and compressor characteristic parameters includes:

[0104] Obtain the saturation temperature corresponding to the system evaporation pressure;

[0105] The virtual condensing pressure is calculated based on the saturation temperature, compressor characteristic parameters, and the preset first fitting formula.

[0106] The saturation temperature mentioned above can be understood as the boiling point temperature of a liquid under a certain evaporation pressure. That is, at this temperature, the refrigerant begins to rapidly evaporate from a liquid to form a gas.

[0107] Typically, for a given substance, there is a definite relationship between evaporation pressure and saturation temperature. As the temperature increases, the evaporation pressure also increases, and vice versa. This relationship can be described by a saturation pressure curve. Therefore, the saturation temperature at the system's evaporation pressure can be obtained using a pre-established pressure-temperature chart or formula.

[0108] The first fitting relationship is a fitting formula used to calculate the virtual condensing pressure of the air conditioning system in cooling mode.

[0109] Optionally, the first fitting equation is as follows: Pcx=R1×Te^a1×W^b1×TD^c1×TS^d1+R2×Te^a2×W^b2×TD^c2×TS^d2+R3×Te^a3×W^b3×TD^c3×TS^d3+…+Rn×Te^an×W^bn×TD^cn×TS^dn

[0110] Where Pcx represents the virtual condensing pressure, R1-Rn, a1-an, b1-bn, c1-cn and d1-dn all represent inherent coefficients, which are determined by the compressor, refrigerant and refrigeration oil, Te represents the saturation temperature of the system evaporation pressure, W represents the input power of the compressor, TD represents the discharge temperature of the compressor and TS represents the suction temperature of the compressor.

[0111] It is worth noting that the above is only an exemplary first fitting relationship, but it does not constitute a limitation on the scope of protection of this invention.

[0112] In this embodiment, the virtual condensing pressure at the theoretical level is calculated by substituting the saturation temperature of the system evaporation pressure and the compressor characteristic parameters into a pre-established first fitting relationship.

[0113] In some embodiments of this application, the process of determining the system condensing pressure based on the virtual condensing pressure and the degree of frequency variation includes:

[0114] When the frequency variation is less than a preset threshold, the system condensing pressure is determined by using the internal and outlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual condensing pressure.

[0115] When the frequency change is greater than or equal to a preset threshold, the virtual condensing pressure is used as the system condensing pressure.

[0116] The aforementioned preset threshold is a frequency change value pre-set based on practical experience, such as 10%.

[0117] The internal temperature refers to the refrigerant temperature inside the outdoor heat exchanger. In cooling mode, the outlet temperature refers to the refrigerant temperature when the refrigerant condenses from gas to liquid inside the outdoor heat exchanger and is output.

[0118] The saturation temperature mentioned above can be understood as the temperature at which the refrigerant gas transforms into a liquid under a certain condensation pressure; that is, the temperature at which the gas condenses into a liquid under a specific pressure. Generally, as the condensation pressure increases, the condensation temperature also increases, because higher pressures require higher temperatures to condense the gas into a liquid. Similarly, the saturation temperature corresponding to the system condensation pressure can be obtained using a pre-established pressure-temperature chart or formula.

[0119] In this embodiment, if the frequency change of the compressor is less than the preset threshold, it means that the compressor frequency change is not significant. The system condensing pressure can be calculated by combining the temperature of the refrigerant during the condensation process from gas to liquid by the outdoor heat exchanger (which acts as a condenser) and the saturation temperature of the virtual condensing pressure. However, if the frequency change of the compressor is greater than or equal to the preset threshold, it means that the compressor frequency change is relatively large. In this case, there is no need to consider the temperature parameters of the outdoor heat exchanger, and the virtual condensing pressure can be directly used as the system condensing pressure.

[0120] In some embodiments of this application, the process of determining the system condensing pressure using the internal and outlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual condensing pressure includes:

[0121] Calculate the saturation temperature of the system condensation pressure based on the internal and outlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual condensation pressure.

[0122] The system condensing pressure is obtained from the saturation temperature of the system condensing pressure.

[0123] The formula for calculating the saturation temperature of the system's condensing pressure is as follows: Tc=max(max(Tm,To)+D,Tcx)

[0124] Where Tc represents the saturation temperature of the system condensing pressure, Tm represents the internal temperature of the outdoor heat exchanger, To represents the outlet temperature of the outdoor heat exchanger, Tcx represents the saturation temperature corresponding to the virtual condensing pressure, and D represents the pressure loss constant.

[0125] The system condensing pressure can be obtained from the saturation temperature of the system condensing pressure. Specifically, the system condensing pressure corresponding to the saturation temperature can be obtained by using a pre-established pressure-temperature chart or formula.

[0126] In some embodiments of this application, step 402 above, which determines the system evaporation pressure for controlling the outdoor fan based on the detected system condensing pressure and compressor characteristic parameters, includes:

[0127] The virtual evaporation pressure is calculated using the system condensing pressure and compressor characteristic parameters; the compressor characteristic parameters include at least one of the compressor input power, compressor discharge temperature, and compressor suction temperature.

[0128] The degree of frequency change of the compressor is determined based on the compressor operating frequency detected twice consecutively;

[0129] The system evaporation pressure is determined based on the virtual evaporation pressure and the degree of frequency variation.

[0130] The aforementioned virtual evaporation pressure can be understood as the theoretical compressor suction pressure determined by the compressor characteristics.

[0131] The compressor operating frequency refers to the actual frequency of the compressor. In heating mode, this frequency changes dynamically as the deviation between the system condensing pressure and the target condensing pressure changes.

[0132] In this embodiment, the theoretical virtual evaporation pressure is calculated using the system condensing pressure and compressor characteristic parameters. Then, the final system evaporation pressure is obtained by combining the compressor frequency variation and the virtual evaporation pressure, thereby improving the accuracy of the system evaporation pressure.

[0133] In some embodiments of this application, the process of calculating the virtual evaporation pressure using the system condensing pressure and the compressor characteristic parameters includes:

[0134] Obtain the saturation temperature corresponding to the system condensation pressure;

[0135] The virtual evaporation pressure is calculated based on the saturation temperature, the compressor characteristic parameters, and the preset second fitting formula.

[0136] The saturation temperature corresponding to the system condensing pressure can be understood as the temperature at which the refrigerant gas transforms into a liquid under a certain condensing pressure; that is, the temperature at which the gas condenses into a liquid under a specific pressure. Similarly, the saturation temperature corresponding to the system condensing pressure can be obtained using a pre-established pressure-temperature chart or formula.

[0137] The second fitting relationship is a fitting formula used to calculate the virtual evaporation pressure of the air conditioning system in heating mode.

[0138] Optionally, the second fitting relationship is as follows: Pex=S1×Tc^e1×W^f1×TD^g1×TS^h1+S2×Tc^e2×W^f2×TD^g2×TS^h2+S3×Tc^e3×W^f3×TD^g3×TS^h3+…+Sn×Tc^en×W^fn×TD^gn×TS^hn

[0139] Where Pex represents the virtual evaporation pressure, S1-Sn, e1-en, f1-fn, g1-gn, and h1-hn all represent inherent coefficients, which are determined by the compressor, refrigerant, and refrigeration oil, Tc represents the saturation temperature of the system condensation pressure, W represents the input power of the compressor, TD represents the discharge temperature of the compressor, and TS represents the suction temperature of the compressor.

[0140] It is worth noting that the above is only an exemplary second fitting relationship, but it does not constitute a limitation on the scope of protection of this invention.

[0141] In this embodiment, the virtual evaporation pressure at the theoretical level is calculated by substituting the saturation temperature of the system condensation pressure and the compressor characteristic parameters into a pre-established second fitting relationship.

[0142] In some embodiments of this application, the process of determining the system evaporation pressure based on the virtual evaporation pressure and the degree of frequency variation includes:

[0143] When the frequency variation is less than a preset threshold, the system evaporation pressure is determined by using the internal temperature and inlet temperature of the outdoor heat exchanger and the saturation temperature corresponding to the virtual evaporation pressure.

[0144] When the frequency change is greater than or equal to a preset threshold, the virtual evaporation pressure is used as the system evaporation pressure.

[0145] The preset threshold is a frequency change value that is pre-set based on practical experience, such as 10%.

[0146] Internal temperature refers to the refrigerant temperature inside the outdoor heat exchanger. In heating mode, inlet temperature refers to the refrigerant temperature when the refrigerant evaporates from liquid to gas inside the outdoor heat exchanger.

[0147] The saturation temperature mentioned above can be understood as the boiling point temperature of a liquid under a certain evaporation pressure, that is, at this temperature, the refrigerant begins to rapidly evaporate from a liquid to a gas. Similarly, the saturation temperature corresponding to a virtual evaporation pressure can be obtained using a pre-established pressure-temperature chart or formula.

[0148] In this embodiment, if the frequency change of the compressor is less than the preset threshold, it means that the compressor frequency change is not significant. The system evaporation pressure can be calculated by combining the temperature of the refrigerant during the process of evaporating from liquid to gas by the outdoor heat exchanger (which acts as an evaporator) and the saturation temperature of the virtual evaporation pressure. However, if the frequency change of the compressor is greater than or equal to the preset threshold, it means that the compressor frequency change is relatively large. In this case, there is no need to consider the temperature parameters of the outdoor heat exchanger, and the virtual evaporation pressure can be directly used as the system evaporation pressure.

[0149] In some embodiments of this application, the process of determining the system evaporation pressure using the internal temperature and inlet temperature of the outdoor heat exchanger and the saturation temperature corresponding to the virtual evaporation pressure includes:

[0150] Calculate the saturation temperature of the system evaporation pressure based on the internal and inlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual evaporation pressure.

[0151] The system evaporation pressure is obtained from the saturation temperature of the system evaporation pressure.

[0152] The formula for calculating the saturation temperature of the system evaporation pressure is as follows: Te=min(min(Tm,Ti)+D,Tex)

[0153] Where Te represents the saturation temperature of the system evaporation pressure, Tm represents the internal temperature of the outdoor heat exchanger, Ti represents the inlet temperature of the outdoor heat exchanger, Tex represents the saturation temperature corresponding to the virtual evaporation pressure, and D represents the pressure loss constant.

[0154] The system evaporation pressure can be obtained from the saturation temperature of the system evaporation pressure. Specifically, the system evaporation pressure corresponding to the saturation temperature can be obtained by using a pre-established pressure-temperature chart or formula.

[0155] The present invention also provides a pressure detection device corresponding to the pressure detection method provided in the foregoing embodiments, for performing the pressure detection method described above.

[0156] Figure 5 is a schematic diagram of a pressure detection device for an air conditioning system according to an exemplary embodiment of the present invention. This device is used to perform the pressure detection method provided in any of the above embodiments. As shown in Figure 5, the pressure detection device includes:

[0157] The refrigeration detection module 510 is used to acquire the system evaporation pressure detected by the pressure sensor for controlling the compressor when the air conditioning system is in refrigeration mode, and to determine the system condensation pressure for controlling the outdoor fan based on the detected system evaporation pressure and compressor characteristic parameters.

[0158] The heating detection module 520 is used to acquire the system condensing pressure detected by the pressure sensor for controlling the compressor when the air conditioning system is in heating mode, and to determine the system evaporating pressure for controlling the outdoor fan based on the detected system condensing pressure and compressor characteristic parameters.

[0159] The specific implementation process of the functions and roles of each unit in the above device can be found in the implementation process of the corresponding steps in the above method, and will not be repeated here.

[0160] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this application according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0161] The pressure detection device and the pressure detection method provided in this application are based on the same inventive concept and have the same beneficial effects as the methods they employ, operate, or implement.

[0162] This application also provides a computer-readable storage medium corresponding to the pressure detection method provided in the foregoing embodiments. Please refer to Figure 6, which shows a computer-readable storage medium 30, on which a computer program (i.e., a program product) is stored. When the computer program is run by a processor, it executes the pressure detection method provided in any of the foregoing embodiments.

[0163] It should be noted that examples of the computer-readable storage medium may also include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical and magnetic storage media, which will not be elaborated here.

[0164] The computer-readable storage medium provided in the above embodiments of this application and the pressure detection method provided in the embodiments of this application are based on the same inventive concept and have the same beneficial effects as the methods adopted, run or implemented by the applications stored therein.

[0165] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the following claims.

[0166] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method of detecting pressure of an air conditioning system, characterized by, The method includes: When the air conditioning system is in cooling mode, the system evaporation pressure detected by the pressure sensor for controlling the compressor is acquired, and the system condensation pressure for controlling the outdoor fan is determined based on the detected system evaporation pressure and compressor characteristic parameters. When the air conditioning system is in heating mode, the system condensing pressure detected by the pressure sensor for controlling the compressor is acquired, and the system evaporating pressure for controlling the outdoor fan is determined based on the detected system condensing pressure and the compressor characteristic parameters.

2. The method of claim 1, wherein, The process of determining the system condensing pressure for controlling the outdoor fan based on the detected system evaporating pressure and compressor characteristic parameters includes: The virtual condensing pressure is calculated using the system evaporation pressure and the compressor characteristic parameters; the compressor characteristic parameters include at least one of the compressor input power, compressor discharge temperature, and compressor suction temperature. The degree of frequency change of the compressor is determined based on two consecutive detected compressor operating frequencies; The system condensing pressure is determined based on the virtual condensing pressure and the degree of frequency change.

3. The method of claim 2, wherein, The calculation of the virtual condensing pressure using the system evaporation pressure and the compressor characteristic parameters includes: Obtain the saturation temperature corresponding to the evaporation pressure of the system; The virtual condensing pressure is calculated based on the saturation temperature, the compressor characteristic parameters, and a preset first fitting formula; the first fitting formula is used to calculate the virtual condensing pressure of the air conditioning system in cooling mode.

4. The method of claim 2, wherein, Determining the system condensing pressure based on the virtual condensing pressure and the degree of frequency change includes: When the frequency change is less than a preset threshold, the system condensing pressure is determined using the internal and outlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual condensing pressure. If the frequency change is greater than or equal to a preset threshold, the virtual condensing pressure is used as the system condensing pressure.

5. The method as described in claim 4, characterized in that, The determination of the system condensing pressure using the internal and outlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual condensing pressure includes: The saturation temperature of the system condensation pressure is calculated based on the internal and outlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual condensation pressure. The system condensing pressure is obtained based on the saturation temperature of the system condensing pressure.

6. The method of claim 1, wherein, The step of determining the system evaporation pressure for controlling the outdoor fan based on the detected system condensing pressure and compressor characteristic parameters includes: The virtual evaporation pressure is calculated using the system condensing pressure and the compressor characteristic parameters; the compressor characteristic parameters include at least one of the compressor input power, compressor discharge temperature, and compressor suction temperature. The degree of frequency change of the compressor is determined based on two consecutive detected compressor operating frequencies; The system evaporation pressure is determined based on the virtual evaporation pressure and the degree of frequency change.

7. The method of claim 6, wherein, The calculation of the virtual evaporation pressure using the system condensing pressure and the compressor characteristic parameters includes: Obtain the saturation temperature corresponding to the condensation pressure of the system; The virtual evaporation pressure is calculated based on the saturation temperature, the compressor characteristic parameters, and a preset second fitting formula; the second fitting formula is used to calculate the virtual evaporation pressure of the air conditioning system in heating mode.

8. The method of claim 6, wherein, The step of determining the system evaporation pressure based on the virtual evaporation pressure and the degree of frequency change includes: When the frequency change is less than a preset threshold, the system evaporation pressure is determined using the internal temperature and inlet temperature of the outdoor heat exchanger and the saturation temperature corresponding to the virtual evaporation pressure. If the frequency change is greater than or equal to a preset threshold, the virtual evaporation pressure is taken as the system evaporation pressure.

9. The method of claim 8, wherein, The determination of the system evaporation pressure using the internal and inlet temperatures of the outdoor heat exchanger and the saturation temperature corresponding to the virtual evaporation pressure includes: The saturation temperature of the system evaporation pressure is calculated based on the internal temperature and inlet temperature of the outdoor heat exchanger and the saturation temperature corresponding to the virtual evaporation pressure. The system evaporation pressure is obtained based on the saturation temperature of the system evaporation pressure.

10. A pressure detection device of an air conditioning system, characterized by comprising: The device includes: The refrigeration detection module is used to acquire the system evaporation pressure detected by the pressure sensor for controlling the compressor when the air conditioning system is in refrigeration mode, and to determine the system condensation pressure for controlling the outdoor fan based on the detected system evaporation pressure and compressor characteristic parameters. The heating detection module is used to acquire the system condensing pressure detected by the pressure sensor for controlling the compressor when the air conditioning system is in heating mode, and to determine the system evaporating pressure for controlling the outdoor fan based on the detected system condensing pressure and compressor characteristic parameters.

11. An air conditioning system comprising a compressor, an indoor unit, and a four-way valve, characterized by, It also includes the pressure detection device for the air conditioning system as described in claim 10; A pressure sensor is installed on the connecting pipe between the first end of the four-way valve and one end of the indoor unit. The pressure sensor is used to detect the evaporation pressure of the air conditioning system when the air conditioning system is in cooling mode, and to detect the condensation pressure of the air conditioning system when the air conditioning system is in heating mode.

12. A computer readable storage medium having stored thereon a computer program, characterized in that, When the program is executed by a processor, it implements the steps of the method as described in any one of claims 1-9.

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