A multi-split air conditioner

Abstract

The present application discloses a multi-split air conditioner, comprising a compressor, an exhaust pressure sensor, a water-fluorine heat exchanger, an outdoor heat exchanger, an outdoor fan, an outlet water temperature sensor, and a controller; the exhaust pressure sensor is used to detect the condensing pressure; the outdoor heat exchanger is connected in parallel with the water-fluorine heat exchanger, with a common end connected to the exhaust port; the outdoor fan is provided corresponding to the outdoor heat exchanger; the outlet water temperature sensor is used to obtain the outlet water temperature of the water-fluorine heat exchanger; the controller is connected to the exhaust pressure sensor, the outdoor fan, and the outlet water temperature sensor, and is configured with a hot water mode: receiving the outlet water temperature and condensing pressure, and setting a first hot water target condensing pressure based on the outlet water temperature; and controlling the outdoor fan speed to increase or decrease the condensing pressure to be controlled near the first hot water target condensing pressure. The present invention sets the first hot water target condensing pressure based on the outlet water temperature, stabilizes the condensing pressure near the first hot water target condensing pressure, increases the hot water temperature, and meets the user's demand for high-temperature hot water.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioning, and in particular to a multi-split air conditioner. Background Art

[0002] In traditional refrigeration systems, the unit adjusts the outdoor unit fan speed by comparing the system condensing pressure with the set target condensing pressure. Specifically, when the system condensing pressure exceeds the target, the fan speed is increased to improve condensation and reduce the condensing pressure. When the system condensing pressure does not exceed the target, the fan speed is decreased to increase the condensing pressure, thereby maintaining the system condensing pressure near the target and ensuring the stability of the refrigeration cycle.

[0003] The outdoor unit of a multi-split system with natural fluorine and ground water has a built-in water-fluorine heat exchanger. This is connected in series or parallel with the outdoor heat exchanger, ensuring that the water-fluorine heat exchanger is always located between the system's exhaust and liquid-side shut-off valves, thereby recovering waste heat from condensation. However, when the system is cooling, both the outdoor heat exchanger and the water-fluorine heat exchanger function as condensers, causing a significant amount of the system's waste heat to be dissipated through the outdoor heat exchanger. The amount of heat recovered by the water-fluorine heat exchanger is limited, and the hot water it provides is not high enough to meet demand for hot water.

[0004] The above information disclosed in this background technology is only used to increase the understanding of the background technology of this application. Therefore, it may contain information that does not constitute the prior art known to ordinary technicians in this field. Summary of the Invention

[0005] In response to the problems pointed out in the background technology, the present application provides a multi-split air conditioner, which sets a first hot water target condensing pressure in hot water mode, and controls the outdoor fan speed to control the condensing pressure near the first hot water target condensing pressure, thereby increasing the temperature of the hot water recovered by condensing heat, meeting people's demand for hot water temperature, and improving user experience.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0007] A multi-split air conditioner includes an outdoor side, comprising:

[0008] A compressor including an exhaust port and an intake port;

[0009] an exhaust pressure sensor, which is used to detect the refrigerant pressure at the exhaust port, recorded as condensing pressure;

[0010] A water-fluorine heat exchanger comprising a refrigerant passage and a water passage; one end of the refrigerant passage is connected to the exhaust port, and is used to exchange heat and condense the refrigerant passing through the refrigerant passage with the water passing through the water passage, thereby increasing the temperature of the water in the water passage;

[0011] An outdoor heat exchanger, one end of which is connected to the exhaust port and is connected in parallel with the water-fluorine heat exchanger, for condensing the refrigerant during the refrigeration cycle;

[0012] an outdoor fan, which is provided corresponding to the outdoor heat exchanger and is used to accelerate the flow of air inside and around the outdoor heat exchanger to accelerate heat exchange;

[0013] An outlet water temperature sensor, used to obtain the outlet water temperature of the water-fluorine heat exchanger;

[0014] The controller connected to the exhaust pressure sensor, the outdoor fan, and the outlet water temperature sensor is configured with a hot water mode. In the hot water mode, the controller receives the outlet water temperature and the condensing pressure, and sets a first hot water target condensing pressure according to the outlet water temperature; and controls the outdoor fan speed to increase or decrease so that the condensing pressure is controlled near the first hot water target condensing pressure.

[0015] In some embodiments of the present application, the controller is further configured with a no hot water demand mode and a no hot water target condensing pressure;

[0016] The controller is further configured to receive the condensing pressure in the no-hot water demand mode, and control the outdoor fan speed to increase or decrease so that the condensing pressure is controlled near the no-hot water target condensing pressure.

[0017] In some embodiments of the present application, the controller is further configured with a first hot water temperature correction value;

[0018] The first hot water target condensing pressure is equal to the refrigerant saturation pressure corresponding to the sum of the outlet water temperature and the first hot water temperature correction value.

[0019] In some embodiments of the present application, further comprising:

[0020] a temperature acquisition module, electrically connected to the controller, for acquiring the temperature of the controller, recorded as a control temperature, and transmitting the temperature to the controller;

[0021] The controller is further configured with a first condensing pressure correction value, a second condensing pressure correction value greater than the first condensing pressure correction value, a first control temperature threshold, and a second control temperature threshold greater than the first control temperature threshold;

[0022] The configuration of the controller also includes:

[0023] The first hot water target condensing pressure is corrected by subtracting the first condensing pressure correction value, and the first hot water target condensing pressure is corrected by subtracting the second condensing pressure correction value;

[0024] In the hot water mode, the controller receives the control temperature; when the control temperature reaches or falls below the first control temperature threshold, the first hot water target condensing pressure is corrected by subtracting the first condensing pressure correction value; when the first hot water target condensing pressure is corrected by subtracting the first condensing pressure correction value and the control temperature reaches or exceeds the second control temperature threshold, the controller switches to correcting by subtracting the second condensing pressure correction value from the first hot water target condensing pressure;

[0025] When the control temperature reaches the second control temperature threshold or above, the first hot water target condensing pressure is corrected by subtracting the second condensing pressure correction value; when the first hot water target condensing pressure is corrected by subtracting the second condensing pressure correction value and the control temperature reaches the first control temperature threshold or below, the correction is switched to the first hot water target condensing pressure subtracting the first condensing pressure correction value.

[0026] In some embodiments of the present application, the configuration of the controller further includes:

[0027] Set the condensing pressure allowable threshold;

[0028] When the first hot water target condensing pressure reaches or exceeds the maximum value of the heat dissipation condensing pressure allowable threshold value, the first hot water target condensing pressure is equal to the maximum value of the set condensing pressure allowable threshold value;

[0029] When the first hot water target condensing pressure reaches or is below the minimum value of the heat dissipation condensing pressure allowable threshold, the first hot water target condensing pressure is equal to the minimum value of the set condensing pressure allowable threshold.

[0030] In some embodiments of the present application, the configuration of the controller also includes: in the hot water mode, when the first hot water target condensing pressure does not exceed the no hot water target condensing pressure, the first hot water target condensing pressure is equal to the no hot water target condensing pressure.

[0031] In some embodiments of the present application, the first condensing pressure correction value is 0 MPa; the second condensing pressure correction value is 0.3 MPa; the first control temperature threshold is 63°C, and the second control temperature threshold is 65°C.

[0032] In some embodiments of the present application, the set condensation pressure allowable threshold is between 2.4 MPa and 3.4 MPa.

[0033] Some embodiments of the present application further include a hot water temperature setting module, which is in communication with the controller and is used to set the hot water temperature and transmit it to the controller;

[0034] The controller is further configured with a second hot water temperature correction value, a second hot water target condensing pressure, and a third hot water target condensing pressure; the controller is further configured with:

[0035] The second hot water target condensing pressure is equal to the refrigerant saturation pressure corresponding to the sum of the hot water temperature and the second hot water temperature correction value;

[0036] The third hot water target condensing pressure is equal to the refrigerant saturation pressure corresponding to the hot water temperature;

[0037] In the hot water mode, the compressor control mode includes a frequency increase control mode, a frequency decrease control mode, and a frequency maintenance operation mode;

[0038] When the condensing pressure reaches or is lower than the smaller of the first hot water target condensing pressure and the third hot water target condensing pressure, the compressor operates in the frequency-increasing control mode; when the condensing pressure reaches or is higher than the larger of the first hot water target condensing pressure and the third hot water target condensing pressure while the compressor is in the frequency-increasing control mode, the compressor switches to the frequency-maintaining operation mode.

[0039] When the condensing pressure reaches or exceeds the second hot water target condensing pressure, the compressor operates in the frequency reduction control mode; when the compressor is in the frequency reduction control mode and the condensing pressure reaches or exceeds the larger of the first hot water target condensing pressure and the third hot water target condensing pressure, the compressor switches to the frequency maintenance operation mode;

[0040] When the compressor is in the frequency maintaining operation mode and the condensing pressure reaches the second hot water target condensing pressure or above, the compressor switches to the frequency reduction control mode; when the condensing pressure reaches the smaller of the first hot water target condensing pressure and the third hot water target condensing pressure or below, the compressor switches to the frequency increase control mode.

[0041] In some embodiments of the present application, the first hot water temperature correction value and the second hot water temperature correction value are both 6°C.

[0042] Compared with the prior art, the advantages and positive effects of the present invention are: the multi-split air conditioner of the present invention sets the first hot water target condensing pressure by detecting the hot water temperature at the outlet of the water-fluorine heat exchanger, and increases or decreases the condensing pressure by controlling the speed increase or decrease of the outdoor fan to stabilize the condensing pressure near the first hot water target condensing pressure, so that the hot water temperature provided by the device that provides hot water through heat condensation heat recovery of the water-fluorine heat exchanger is high, meeting the user's demand for high-temperature hot water and improving the user experience.

[0043] Other features and advantages of the present invention will become more apparent after reading the detailed description of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0045] Figure 1 Schematic diagram of the outdoor system structure according to an embodiment;

[0046] Figure 2 is a schematic diagram of control connections according to an embodiment;

[0047] Figure 3 1 is a schematic diagram of a hot water mode control process according to an embodiment;

[0048] Figure 4 1 is a schematic diagram of a hot water mode control process according to an embodiment;

[0049] Figure 5 1 is a schematic diagram of a process for obtaining a first hot water target condensing pressure according to an embodiment;

[0050] Figure 6 is a schematic diagram of temperature control correction according to an embodiment;

[0051] Figure 7 1 is a schematic diagram of a process for obtaining a first hot water target condensing pressure according to an embodiment;

[0052] Figure 8 1 is a schematic diagram of a process for obtaining a first hot water target condensing pressure according to an embodiment;

[0053] Figure 9 is a schematic diagram of a compressor frequency control process according to an embodiment;

[0054] Figure 10 1 is a schematic diagram of the electronic expansion valve opening control process according to an embodiment;

[0055] Figure 11 1 is a schematic diagram of the electronic expansion valve opening control process according to an embodiment.

[0056] Reference numerals:

[0057] 1. Compressor; 2. Water-fluorine heat exchanger; 3. Outdoor heat exchanger; 4. First electronic expansion valve; 5. Second electronic expansion valve; 6. Four-way valve; 7. Exhaust pressure sensor; 8. Outlet water temperature sensor; 9. Inlet water temperature sensor; 10. Outdoor fan; 20. Controller; 30. Hot water temperature setter; 40. Outdoor ambient temperature sensor; 50. Water pump; 11. Exhaust port; 12. Inlet port; 21. Refrigerant flow path; 22. Water flow path.

[0058] Cfin1, first condensing pressure correction value; Cfin2, second condensing pressure correction value; Tfin1, first control temperature threshold; Tfin2, second control temperature threshold; Pdo, first hot water target condensing pressure; Pds, second hot water target condensing pressure; Pdc, third hot water target condensing pressure; P1, minimum value of the allowable threshold of condensing pressure; P2, maximum value of the allowable threshold of condensing pressure; Two, outlet water temperature; Tws, hot water temperature; Twi, inlet water temperature; Ta, outdoor ambient temperature; Ta1, first ambient reference temperature; Ta2, second ambient reference temperature; Pd, condensing pressure; Evo, first electronic expansion valve opening; Evw, second electronic expansion valve opening. Implementation Method

[0059] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0060] In the description of this application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0061] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. Throughout this application, unless otherwise specified, "plurality" means two or more.

[0062] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0063] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0064] The disclosure below provides many different embodiments or examples for realizing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0065] An air conditioner performs its refrigeration cycle by using a compressor, condenser, expansion valve, and evaporator. The refrigeration cycle involves a series of processes involving compression, condensation, expansion, and evaporation to cool or heat the indoor space.

[0066] Low-temperature, low-pressure refrigerant enters the compressor, which compresses it into high-temperature, high-pressure refrigerant gas and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, releasing heat into the surrounding environment through the condensation process.

[0067] The expansion valve expands the high-temperature, high-pressure liquid refrigerant condensed in the condenser to a lower-pressure liquid. The evaporator evaporates the refrigerant expanded in the expansion valve and returns the low-temperature, low-pressure refrigerant gas to the compressor. The evaporator achieves cooling by utilizing the latent heat of evaporation to exchange heat with the material being cooled. Throughout this cycle, the air conditioner regulates the temperature of the indoor space.

[0068] The outdoor unit of the air conditioner refers to a portion of a refrigeration cycle including a compressor and an outdoor heat exchanger, the indoor unit of the air conditioner includes an indoor heat exchanger, and an expansion valve may be provided in the indoor unit or the outdoor unit.

[0069] The indoor heat exchanger and the outdoor heat exchanger function as a condenser or an evaporator. When the indoor heat exchanger functions as a condenser, the air conditioner functions as a heater in heating mode, and when the indoor heat exchanger functions as an evaporator, the air conditioner functions as a cooler in cooling mode.

[0070] In a specific embodiment, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 The multi-split air conditioner of the present invention includes an outdoor side and an indoor side; the indoor side includes an indoor heat exchanger, floor heating or a hot water tank; the outdoor side includes a compressor 1, a water-fluorine heat exchanger 2, and an outdoor heat exchanger 3; the compressor 1 includes an exhaust port 11 and an air intake port 12; the water-fluorine heat exchanger 2 includes a refrigerant passage 21 and a water passage 22; the outdoor heat exchanger 3 and the refrigerant passage 21 of the water-fluorine heat exchanger 2 are connected in parallel, and one end is connected to the exhaust port 11 of the compressor 1, and the other end is connected to the indoor heat exchanger on the indoor side; the floor heating or hot water tank is connected to the water passage 22 of the water-fluorine heat exchanger 2, and floor heating or hot water supply is achieved by recovering the heat of the refrigerant condensation in the refrigerant passage 21.

[0071] The multi-split air conditioner further includes an exhaust pressure sensor 7, an outdoor fan 10, an outlet water temperature sensor 8, and a controller 20 electrically connected to the exhaust pressure sensor 7, the outdoor fan 10, and the outlet water temperature sensor 8, respectively.

[0072] The exhaust pressure sensor 7, outdoor fan 10, and outlet water temperature sensor 8 are each located inside the outdoor area. The exhaust pressure sensor 7 is located near the exhaust port 11 of the compressor 1 and is used to detect the exhaust pressure at the exhaust port 11 of the compressor 1; that is, to detect the condensing pressure Pd of the multi-split air conditioning system. The outdoor fan 10 is located in correspondence with the outdoor heat exchanger 3 and is used to accelerate the flow of air inside and around the outdoor heat exchanger 3, thereby accelerating the heat exchange between the outdoor heat exchanger 3 and the surrounding air. The outlet water temperature sensor 8 is located near the outlet of the water passage 22 and is used to detect the temperature of the outlet of the water passage 22 of the water-fluorine heat exchanger 2; that is, to detect the outlet water temperature Two of the water-fluorine heat exchanger 2.

[0073] The controller 20 is configured with a hot water mode, which operates within the multi-split air conditioner's refrigeration cycle. Specifically, the controller 20 can operate in hot water mode while the multi-split air conditioner is operating in cooling or dehumidification mode. This mode activates the water-fluorine heat exchanger 2, recovering heat from the condensation process to provide circulating hot water for indoor floor heating or to supply hot water to the hot water tank.

[0074] The configuration of the controller 20 also includes: when operating in hot water mode, receiving the outlet water temperature Two detected by the outlet water temperature sensor 8 and the condensing pressure Pd detected by the exhaust pressure sensor 7; setting the first hot water target condensing pressure Pdo according to the outlet water temperature Two; controlling the speed of the outdoor fan 10 to increase or decrease so that the condensing pressure Pd is controlled near the first hot water target condensing pressure Pdo.

[0075] Specifically, when the condensing pressure Pd reaches and exceeds the first hot water target condensing pressure Pdo, the speed of the outdoor fan 10 is controlled to increase, the heat exchange of the outdoor heat exchanger 3 is strengthened, the condensing pressure Pd of the multi-split air-conditioning system is reduced, and the condensing pressure Pd of the refrigerant in the refrigerant passage 21 of the water-fluorine heat exchanger 2 is reduced, and the condensing temperature of the refrigerant in the refrigerant passage 21 is reduced; when the condensing pressure Pd reaches and falls below the first hot water target condensing pressure Pdo, the speed of the outdoor fan 10 is controlled to decrease, the heat exchange of the outdoor heat exchanger 3 is weakened, and the condensing pressure Pd of the multi-split air-conditioning system is increased, and the condensing pressure of the refrigerant in the refrigerant passage 21 of the water-fluorine heat exchanger 2 is increased, and the condensing temperature of the refrigerant in the refrigerant passage 21 is increased, so as to achieve the purpose of adjusting the condensing pressure Pd of the multi-split air-conditioning system and the condensing pressure Pd of the refrigerant in the refrigerant passage 21 by controlling the speed of the outdoor fan 10, and then adjusting the heat recovery hot water temperature Tws.

[0076] The multi-split air conditioner of this embodiment sets the hot water mode, and sets the first hot water target condensing pressure Pdo according to the outlet water temperature Two in the hot water mode, and controls the rotation speed of the outdoor fan 10 to keep the system's condensing pressure Pd near the first hot water target condensing pressure Pdo, and controls the outlet water temperature Two of the water-fluorine heat exchanger 2 to gradually increase to the required height, thereby ensuring the supply of high-temperature hot water and improving the user experience.

[0077] In a specific embodiment, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 , the controller is also configured with a first hot water temperature correction value; the first hot water target condensing pressure Pdo is equal to the refrigerant saturation pressure corresponding to the sum of the outlet water temperature Two and the first hot water temperature correction value.

[0078] The multi-split air conditioner of this embodiment sets the first hot water temperature correction value so that the first hot water target condensation pressure Pdo is higher than the refrigerant saturation pressure corresponding to the outlet water temperature Two, and the target condensation temperature of the refrigerant in the refrigerant passage 21 of the water-fluorine heat exchanger 2 is higher than the outlet water temperature Two, ensuring that the outlet water temperature Two of the water passage 22 through the condensation action of the water-fluorine heat exchanger 2 gradually increases to the required high water temperature through the setting of the first hot water target condensation pressure Pdo, thereby ensuring the supply of high-temperature hot water to the water-fluorine heat exchanger 2.

[0079] In one embodiment, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 The controller 20 is also configured with a no-hot-water-demand mode. That is, in this mode, the multi-split air conditioner operates in a simple cooling or dehumidification mode without any indoor floor heating units or hot water tanks.

[0080] The controller 20 is also configured with a no-hot-water target condensing pressure; when operating in the no-hot-water demand mode, the controller 20 receives the condensing pressure Pd detected by the exhaust pressure sensor 7, and controls the speed of the outdoor fan 10 to increase or decrease according to the value of the received condensing pressure Pd and the no-hot-water target condensing pressure, so that the condensing pressure Pd is maintained near the no-hot-water target condensing pressure.

[0081] Specifically, when the condensing pressure Pd reaches or exceeds the target condensing pressure without hot water, the speed of the outdoor fan 10 is controlled to increase, strengthening the heat exchange of the outdoor heat exchanger 3 and reducing the condensing pressure Pd of the multi-split air conditioning system. When the condensing pressure Pd reaches or falls below the target condensing pressure without hot water, the speed of the outdoor fan 10 is controlled to decrease, weakening the heat exchange of the outdoor heat exchanger and increasing the condensing pressure Pd of the multi-split air conditioning system. This maintains the pressure of the multi-split air conditioning system within a normal and efficient range.

[0082] In one embodiment, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 8The multi-split system also includes a heat dissipation module, an electrical system, and a first temperature acquisition module; the heat dissipation module is used to dissipate heat for the electrical system; and the outdoor fan 10 also dissipates heat for the heat dissipation module; in order to ensure the normal operation of the electrical system, the speed of the outdoor fan 10 must be guaranteed to ensure the heat dissipation effect of the heat dissipation module.

[0083] The controller 20 is included in the electrical system, and its temperature is the control temperature, which needs to be monitored to ensure the normal operation of the controller 20. The first temperature acquisition module is used to acquire the control temperature, which can be built into the controller 20 or set outside the controller 20, and transmits the acquired control temperature to the controller 20.

[0084] The controller 20 is further configured with a first condensing pressure correction value Cfin1 , a second condensing pressure correction value Cfin2 greater than the first condensing pressure correction value Cfin1 , a first control temperature threshold Tfin1 , and a second control temperature threshold Tfin2 greater than the first control temperature threshold Tfin1 .

[0085] The configuration of the controller 20 also includes:

[0086] The correction of the first hot water target condensing pressure Pdo includes the correction of the first hot water target condensing pressure Pdo minus the first condensing pressure correction value Cfin1 and the correction of the first hot water target condensing pressure Pdo minus the second condensing pressure correction value Cfin2; and the first hot water target condensing pressure Pdo in the correction of the first hot water target condensing pressure Pdo minus the first condensing pressure correction value Cfin1 and the correction of the first hot water target condensing pressure Pdo minus the second condensing pressure correction value Cfin2 are both the original values of the first hot water target condensing pressure Pdo before correction.

[0087] In hot water mode, the controller 20 receives the control temperature obtained by the first temperature acquisition module and determines the control temperature. When the control temperature reaches or falls below the first control temperature threshold Tfin1, the first hot water target condensing pressure Pdo is corrected by subtracting the first condensing pressure correction value Cfin1. When the first hot water target condensing pressure Pdo remains corrected by subtracting the first condensing pressure correction value Cfin1 and the control temperature reaches or rises above the second control temperature threshold Tfin2, the first hot water target condensing pressure Pdo is corrected by subtracting the second condensing pressure correction value Cfin2.

[0088] When the control temperature reaches the second control temperature threshold Tfin2 or above, the first hot water target condensing pressure Pdo is corrected by subtracting the second condensing pressure correction value Cfin2; when the first hot water target condensing pressure Pdo is in the correction of subtracting the second condensing pressure correction value Cfin2 and the control temperature reaches the first control temperature threshold Tfin1 or below, the first hot water target condensing pressure Pdo is changed to be corrected by subtracting the first condensing pressure correction value Cfin1.

[0089] The multi-split air conditioner of this embodiment corrects the first hot water target condensing pressure Pdo to different degrees at different temperatures of the controller 20, ensuring that reducing the fan speed to increase the condensing pressure Pd does not affect the heat dissipation of the electrical system by the heat dissipation module, especially the heat dissipation of the controller 20, thereby ensuring the normal operation of the electrical system, improving the hot water supply temperature, and ensuring the reliability of the system operation.

[0090] In addition, it should be noted that the correction of the first hot water target condensing pressure Pdo is started by subtracting the first condensing pressure correction value Cfin1.

[0091] In a specific embodiment, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 7 The controller 20 is further configured with a condensing pressure allowable threshold; and the configuration of the controller 20 further includes:

[0092] When the first hot water target condensing pressure Pdo exceeds the maximum value P2 of the condensing pressure allowable threshold, the first hot water target condensing pressure Pdo is equal to the maximum value P2 of the condensing pressure allowable threshold; when the first hot water target pressure is lower than the minimum value P1 of the condensing pressure allowable threshold, the first hot water target condensing pressure Pdo is equal to the minimum value P1 of the condensing pressure allowable threshold.

[0093] The multi-split air conditioner of this embodiment sets a condensing pressure allowable threshold value and compares the first hot water target condensing pressure Pdo with the condensing pressure allowable threshold value, so that the first hot water target condensing pressure Pdo is within the condensing pressure allowable threshold value range, thereby ensuring the normal pressure of the multi-split air conditioning system and further ensuring the reliability and efficiency of the operation of the multi-split air conditioning system.

[0094] In a specific embodiment, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 7 , the configuration of the controller 20 further includes:

[0095] In hot water mode, the first hot water target condensing pressure Pdo is compared with the no-hot water target condensing pressure after being corrected by the first condensing pressure correction value Cfin1 or the second condensing pressure correction value Cfin2 and / or determined by the condensing pressure allowable threshold. If the first hot water target condensing pressure Pdo does not exceed the no-hot water target condensing pressure, the first hot water target condensing pressure Pdo is equal to the no-hot water target condensing pressure. However, if the first hot water target condensing pressure Pdo exceeds the no-hot water target condensing pressure, the controller 20 uses the original value or the corrected value of the first hot water target condensing pressure Pdo for control.

[0096] The multi-split air conditioner of this embodiment prevents the condensing pressure Pd of the multi-split air conditioner system from being too low when the outlet water temperature Two is set too low, thereby affecting the efficiency of the multi-split air conditioner system.

[0097] In a specific embodiment, the first hot water temperature correction value ranges from 4 to 7°C; the first hot water temperature correction value is preferably 6°C.

[0098] In a specific embodiment, the first condensing pressure correction value Cfin1 is 0 MPa; the second condensing pressure correction value Cfin2 is 0.3 MPa; the first control temperature threshold Tfin1 and the second control temperature threshold Tfin2 are temperature points, rather than temperature ranges; preferably, the first control temperature threshold Tfin1 is 63°C; the second control temperature threshold Tfin2 is 65°C. Of course, the first control temperature threshold Tfin1 and the second control temperature threshold Tfin2 can also be set to other appropriate values based on the operating temperature of the controller; the first condensing pressure correction value Cfin1 and the second condensing pressure correction value Cfin2 can also be set to appropriate values based on the operating pressure of the refrigerant system of the multi-split air conditioning system.

[0099] In a specific embodiment, the condensation pressure allowable threshold is between 2.4 MPa and 3.4 MPa.

[0100] In a specific embodiment, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 The outdoor side of the multi-split air conditioner also includes a four-way valve 6; one end of the outdoor heat exchanger 3 is connected to the exhaust port 11 of the compressor 1 through the connection between the two ends of the four-way valve 6, and is connected to the intake port 12 of the compressor 1 through the connection between the other two ends of the four-way valve 6; the four-way valve 6 is electrically connected to the controller 20 and is controlled by the controller 20.

[0101] When the multi-split air conditioning system is in a refrigeration cycle, the four-way valve 6 is closed, and one end of the outdoor heat exchanger 3 is connected to the exhaust port 11 through the four-way valve 6; one end of the refrigerant passage 21 of the water-fluorine heat exchanger 2 is connected to the exhaust port 11, ensuring that one end of the water-fluorine heat exchanger 2 is always connected to the exhaust port 11, realizing condensation heat recovery in the cooling mode and dehumidification mode. When the four-way valve 6 is controlled to be open, one end of the outdoor heat exchanger 3 is connected to the air intake port 12 through the four-way valve 6, and the refrigerant is discharged from the exhaust port 11 and enters the water-fluorine heat exchanger 2; after passing through the refrigerant passage 21 of the water-fluorine heat exchanger 2, it enters the outdoor heat exchanger 3; and then enters the compressor 1 through the air intake port 12 through the outdoor heat exchanger 3, realizing a pure floor heating mode in which the water-fluorine heat exchanger 2 condenses and releases heat alone, and the outdoor heat exchanger 3 evaporates and absorbs heat.

[0102] The multi-split air conditioner of this embodiment realizes the cooling mode, heat recovery of the dehumidification mode and the floor heating mode by controlling the four-way valve 6; in addition, in the dehumidification mode, the floor heating can be provided by heat recovery, achieving the effect of dehumidification without cooling, improving the user's comfort, and thus improving the user experience.

[0103] In some specific embodiments, referring to Figure 1 、 Figure 2 , Figure 3 、 Figure 4 、 Figure 5 、 Figure 9 The multi-split air conditioner also includes a hot water temperature setter 30, which is communicated with the controller 20 and is used to set the hot water temperature Tws and transmit the set hot water temperature Tws to the controller; the controller 20 is also configured with a second hot water temperature correction value, a second hot water target condensing pressure Pds, and a third hot water target condensing pressure Pdc.

[0104] The configuration of the controller 20 also includes:

[0105] Whether to execute the hot water mode is determined based on the comparison between the hot water temperature Tws and the outlet water temperature Two; specifically, when the outlet water temperature Two reaches the hot water temperature Tws or above, the simple cooling mode or the dehumidification mode is executed; when the outlet water temperature Two reaches the hot water temperature Tws or below, the hot water mode is executed.

[0106] In some specific embodiments, referring to Figure 1 、 Figure 2 , Figure 3 、 Figure 4 、 Figure 5 、 Figure 9 , the hot water supply can be set to be turned on through the hot water temperature setter 30, and the hot water mode can be started by transmitting the information to the controller 20.

[0107] In some specific embodiments, referring to Figure 1 、 Figure 2 , Figure 3、 Figure 4 、 Figure 5 、 Figure 9 The compressor 1 is connected to the controller 20, and the operating frequency is controlled by the controller 20. The configuration of the controller 20 also includes:

[0108] The second hot water target condensing pressure Pds is equal to the refrigerant saturation pressure corresponding to the sum of the hot water temperature Tws and the second hot water temperature correction value;

[0109] The third hot water target condensing pressure Pdc is equal to the refrigerant saturation pressure corresponding to the hot water temperature Tws;

[0110] In hot water mode, the operation control modes of compressor 1 include frequency increase control mode, frequency reduction control mode, and frequency maintenance operation mode;

[0111] Receive the condensing pressure Pd, and control the compressor 1 to operate in different operation control modes according to the condensing pressure Pd; the details are as follows:

[0112] When the condensing pressure Pd reaches the smaller of the first hot water target condensing pressure Pdo and the third hot water target condensing pressure Pdc or below, the compressor 1 operates in the frequency increase control mode; when the compressor 1 is in the frequency increase control mode, if the condensing pressure Pd reaches the larger of the first hot water target condensing pressure Pdo and the third hot water target condensing pressure Pdc or above, the compressor 1 switches to the frequency maintenance operation mode.

[0113] When the condensing pressure Pd reaches the second hot water target condensing pressure Pds or above, the compressor 1 operates in the frequency reduction control mode; when the compressor 1 is in the frequency reduction control mode and the condensing pressure Pd reaches the larger of the first hot water target condensing pressure Pdo and the third hot water target condensing pressure Pdc or below, the compressor 1 switches to the frequency maintenance operation mode.

[0114] When the compressor 1 is operating in the frequency maintenance operation mode, if the condensing pressure Pd reaches the second hot water target condensing pressure Pds or above, the compressor 1 switches to the frequency reduction control mode; when the condensing pressure Pd reaches the smaller of the first hot water target condensing pressure Pdo and the third hot water target condensing pressure Pdc or below, the compressor 1 switches to the frequency increase control mode.

[0115] The multi-split system of this embodiment controls the operating frequency of the compressor 1 through the condensing pressure Pd, so that the frequency adapts to the power of the multi-split air-conditioning system corresponding to the condensing pressure Pd, thereby reducing power consumption.

[0116] In addition, it should be noted that the frequency operation control of the compressor 1 starts from the frequency increase control mode.

[0117] In a specific embodiment, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 10 、 Figure 11 The outdoor side of the multi-split air conditioner also includes a first electronic expansion valve 4 and a second electronic expansion valve 5, which are respectively connected in series with the outdoor heat exchanger 3 and the refrigerant passage 21, and are located at the end of the outdoor heat exchanger 3 and the refrigerant passage 21 away from the exhaust port 11; one end of the first electronic expansion valve 4 is connected to one end of the second electronic expansion valve 5 and then connected to the indoor heat exchanger, and are respectively used to control the refrigerant flow through the outdoor heat exchanger 3 and the refrigerant passage 21.

[0118] The outdoor side of the multi-split air conditioner also includes an outdoor ambient temperature sensor 40 , which is arranged outdoors and electrically connected to the controller 20 for detecting the outdoor ambient temperature Ta and transmitting it to the controller 20 .

[0119] The outdoor side of the multi-split air conditioner also includes a water pump 50, which is connected in series with the water passage 22, connected to the controller 20, and controlled by the controller 20; when the hot water mode is started, the water pump 50 is controlled to run to circulate the water in the water passage 22.

[0120] The configuration of the controller 20 also includes:

[0121] In the hot water mode, the outdoor ambient temperature Ta is received, and the openings of the first electronic expansion valve 4 and the second electronic expansion valve 5 are controlled according to the outdoor ambient temperature Ta.

[0122] The multi-split air conditioner in this embodiment draws a refrigerant pipeline from the exhaust side of compressor 1 to water-fluorine heat exchanger 2, ensuring that water-fluorine heat exchanger 2 is always on the high-pressure side in any operating mode, and that water passage 22 of water-fluorine heat exchanger 2 can generate hot water. The ratio and efficiency of condensation heat recovery are adjusted by controlling the openings of first and second electronic expansion valves 4 and 5 according to the outdoor ambient temperature. During dehumidification / cooling, the waste condensation heat generated during the cooling process is captured and transported to rooms requiring heat, enabling simultaneous cooling and heating of the same room (without dehumidification), as well as simultaneous cooling or heating of different rooms, or simultaneous cooling and production of domestic hot water. This reduces costs, conserves energy, and enhances the user experience.

[0123] In a specific embodiment, referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 10 、 Figure 11The multi-split air conditioner also includes a first electronic expansion valve 4 and a second electronic expansion valve 5, which are respectively connected in series to one end of the outdoor heat exchanger 3 away from the exhaust port 11 of the compressor 1 and one end of the refrigerant passage 21 of the water-fluorine heat exchanger 2 away from the exhaust port 11 of the compressor 1, and are respectively electrically connected to the controller 20, and their openings are controlled by the controller 20 to adjust the flow rate of the high-temperature and high-pressure refrigerant entering the outdoor heat exchanger 3 and the water-fluorine heat exchanger 2, and then adjust the proportion of recovered waste heat.

[0124] The other end of the outdoor heat exchanger 3 and the other end of the refrigerant passage 21 of the water-fluorine heat exchanger 2 are connected to the indoor heat exchanger via the first electronic expansion valve 4 and the second electronic expansion valve 5, respectively, to throttle and reduce the pressure of the refrigerant discharged from the exhaust port 11 of the compressor 1 through the outdoor heat exchanger 3 and the refrigerant passage 21. When the four-way valve 6 is open, the refrigerant discharged from the exhaust port 11 passes through the refrigerant passage 21 and is throttled and reduced in pressure by the first electronic expansion valve 4 and the second electronic expansion valve 5 in sequence before entering the outdoor heat exchanger 3 and returning to the compressor 1, without entering the indoor heat exchanger.

[0125] The outdoor side of the multi-split air conditioner also includes an inlet water temperature sensor 9, which is arranged near the water inlet of the water passage 22 and is electrically connected to the controller 20 for detecting the inlet water temperature Twi and transmitting it to the controller 20.

[0126] The controller 20 is configured with a first ambient reference temperature Ta1 and a second ambient reference temperature Ta2 that is lower than the first ambient reference temperature Ta1;

[0127] The controller 20 is further configured to, in hot water mode, receive the hot water temperature Tws set by the hot water temperature setter 30; determine whether the outlet water temperature Two reaches the hot water temperature Tws, and if not, start the hot water mode operation; if the outlet water temperature Two reaches the set hot water temperature Tws, only operate in cooling mode or dehumidification mode, and at this time the controller 20 controls the second electronic expansion valve 5 to close.

[0128] When operating in hot water mode, determine whether the outdoor ambient temperature Ta reaches the first ambient reference temperature Ta1 or above; if so, control the first electronic expansion valve 4 to the maximum opening; control the opening of the second electronic expansion valve 5 to half the maximum opening and use the ratio of the outdoor ambient temperature Ta and the inlet water temperature Twi of the water-fluorine heat exchanger 2 as a coefficient for correction.

[0129] Specifically, the opening of the second electronic expansion valve 5 is half of the maximum opening multiplied by the ratio of the outdoor ambient temperature Ta to the inlet water temperature Twi of the water-fluorine heat exchanger 2. It can be expressed as:

[0130] Evw=0.5×Evwmax(Ta / Twi);

[0131] Where,

[0132] Evw is the opening degree of the second electronic expansion valve;

[0133] Evwmax is the maximum opening of the second electronic expansion valve;

[0134] Ta is the outdoor ambient temperature;

[0135] Twi is the water inlet temperature of the water channel.

[0136] In the multi-split air conditioner of this embodiment, when the outdoor temperature reaches or exceeds the first ambient reference temperature Ta1, the first ambient reference temperature Ta1 is set to the relatively high outdoor ambient temperature Ta. At this time, the exhaust pressure of the multi-split air conditioner is affected by the high outdoor ambient temperature and is high, generating a large amount of condensation heat. In this case, by opening the first electronic expansion valve 4 to the maximum, the heat exchange capacity of the outdoor heat exchanger 3 is increased, thereby ensuring the cooling effect of the unit.

[0137] The opening of the second electronic expansion valve 5 is directly proportional to the outdoor ambient temperature Ta and inversely proportional to the inlet water temperature Twi. Specifically, when the outdoor ambient temperature Ta is high and the exhaust pressure (condensing pressure Pd) is high, the opening of the second electronic expansion valve 5 is increased proportionally to the outdoor ambient temperature Ta, increasing the refrigerant flow through the refrigerant passage 21 and increasing the amount of condensation heat recovered. The opposite is also true. As the inlet water temperature Twi of the water passage 22 increases, the opening is decreased proportionally to Twi to prevent the outlet water temperature Two in the water passage 22 from being too high and affecting condensation efficiency. As the inlet water temperature Twi of the water passage 22 decreases, the opening is increased proportionally to Twi to increase heat recovery and prevent the refrigerant passing through the second electronic expansion valve 5 from being in a two-phase state and affecting the cooling effect.

[0138] The controller 20 is also configured with a condensing pressure correction parameter, and the controller 20 is also configured to set the opening of the first electronic expansion valve 4 and the second electronic expansion valve 5 according to the relationship between the condensing pressure Pd and the second hot water target condensing pressure Pds and the third hot water target condensing pressure Pdc when the outdoor ambient temperature Ta is between the first ambient reference temperature Ta1 and the second ambient reference temperature Ta2.

[0139] Specifically include:

[0140] When the condensing pressure Pd reaches the second hot water target condensing pressure Pds or above, the first electronic expansion valve 4 operates at the maximum opening; the opening of the second electronic expansion valve 5 is half of its maximum opening multiplied by the ratio of the outdoor ambient temperature Ta to the water inlet temperature of the water-fluorine heat exchanger 2.

[0141] At this time, the multi-split air-conditioning unit is in a suitable outdoor ambient temperature Ta, and its cooling capacity is relatively sufficient; if the system condensing pressure Pd is high at this time, the condensing pressure Pd may exceed the first hot water target condensing pressure Pdo, resulting in a decrease in the cooling effect; to ensure the cooling effect, when the condensing pressure Pd reaches and exceeds the second hot water target condensing pressure Pds, the first electronic expansion valve 4 operates at the maximum opening, increasing the heat exchange capacity of the outdoor heat exchanger 3 to ensure the cooling effect; the opening of the second electronic expansion valve 5 is half of its maximum opening multiplied by the ratio of the outdoor ambient temperature Ta to the inlet water temperature Twi of the water-fluorine heat exchanger 2; the opening of the second electronic expansion valve 5 is adjusted according to the outdoor ambient temperature Ta and the inlet water temperature Twi to prevent the refrigerant passing through the second electronic expansion valve 5 from being in a two-phase state and affecting the cooling effect.

[0142] When the condensing pressure Pd is between the third hot water target condensing pressure Pdc and the second hot water target condensing pressure Pds, the opening of the first electronic expansion valve 4 is half of its maximum opening and the sum of the difference between its maximum opening through the condensing pressure Pd and the third hot water target condensing pressure Pdc divided by the difference between the second hot water target condensing pressure Pds and the third hot water target condensing pressure Pdc corrected by the proportional coefficient; the opening of the second electronic expansion valve 5 is half of its maximum opening and the difference between its maximum opening through the condensing pressure Pd and the third hot water target condensing pressure Pdc divided by the difference between the second hot water target condensing pressure Pds and the third hot water target condensing pressure Pdc corrected by the proportional coefficient. That is to say, the condensing pressure correction parameter is equal to the ratio of the difference between the condensing pressure Pd and the third hot water target condensing pressure Pdc to the difference between the second hot water target condensing pressure Pds and the third hot water target condensing pressure Pdc; the opening of the first electronic expansion valve 4 is controlled to be equal to the sum of half of its full opening and the condensing pressure correction parameter multiplied by its full opening; the opening of the second electronic expansion valve 5 is controlled to be equal to the difference between half of its full opening and the condensing pressure correction parameter multiplied by its full opening.

[0143] That is, the opening of the first electronic expansion valve 4 is equal to the value of its maximum opening multiplied by the difference between the condensing pressure Pd and the third hot water target condensing pressure Pdc divided by the difference between the second hot water target condensing pressure Pds and the third hot water target condensing pressure Pdc plus half of the maximum opening of the first electronic expansion valve 4; the opening of the second electronic expansion valve 5 is equal to half of its maximum opening minus the value of the maximum opening multiplied by the difference between the condensing pressure Pd and the third hot water target condensing pressure Pdc divided by the difference between the second hot water target condensing pressure Pds and the third hot water target condensing pressure Pdc.

[0144] That is, EVo=(0.5+(Pd-Pdc) / (Pds-Pdc))×EVomax;

[0145] EVw=(0.5-(Pd-Pdc) / (Pds-Pdc))×EVwmax;

[0146] in,

[0147] EVo is the opening degree of the first electronic expansion valve;

[0148] EVw is the opening degree of the second electronic expansion valve;

[0149] EVomax is the maximum opening of the first electronic expansion valve;

[0150] EVwmax is the maximum opening of the second electronic expansion valve;

[0151] Pd is the condensation pressure;

[0152] Pds is the second hot water target condensing pressure;

[0153] Pdc is the third hot water target condensing pressure.

[0154] When operating in hot water mode, the water temperature can only reach the hot water temperature Tws if the refrigerant condensing temperature is higher than the set hot water temperature Tws. Therefore, we introduce two parameters: the third hot water target condensing pressure Pdc and the second hot water target condensing pressure Pds. The third hot water target condensing pressure Pdc is equal to the refrigerant saturation pressure corresponding to the hot water temperature Tws. Only when the actual condensing pressure Pd reaches the third hot water target condensing pressure Pdc or above, can the water temperature reach the set hot water temperature Tws. The second hot water target condensing pressure Pds is the set maximum condensing pressure of the unit system, which is equal to The set hot water temperature Tws and the second hot water temperature correction value correspond to the refrigerant saturation pressure; therefore, when the condensing pressure Pd of the multi-split air-conditioning unit system is between the third hot water target condensing pressure Pdc and the second hot water target condensing pressure Pds, the opening of the first electronic expansion valve 4 and the second electronic expansion valve 5 are controlled by setting parameters related to the third hot water target condensing pressure Pdc and the second hot water target condensing pressure Pds, so that the pressure of the multi-split air-conditioning system is maintained between the third hot water target condensing pressure Pdc and the second hot water target condensing pressure Pds for stable operation, thereby improving the reliability of condensation heat recovery.

[0155] When the condensing pressure Pd reaches the third hot water target condensing pressure Pdc or below, the first electronic expansion valve 4 operates at half of its maximum opening; the second electronic expansion valve 5 operates at half of its maximum opening.

[0156] That is, when the condensing pressure Pd of the multi-split air-conditioning unit system is less than the third hot water target condensing pressure Pdc, the system cannot make the water temperature reach the set hot water temperature Tws; at this time, the first electronic expansion valve 4 and the second electronic expansion valve 5 are controlled to maintain half of their maximum openings, reduce the refrigerant flow of the outdoor heat exchanger 3, and increase the refrigerant flow of the water-fluorine heat exchanger 2, so that the water temperature rises slowly; as the water temperature rises, the condensing pressure Pd of the unit system will also rise to a certain extent until it reaches the third hot water target condensing pressure Pdc, and then high water temperature hot water supply control is performed.

[0157] The controller 20 is further configured such that when the outdoor ambient temperature Ta reaches or is below the second ambient reference temperature Ta2 , the first electronic expansion valve 4 operates at half its maximum opening; and the second electronic expansion valve 5 operates at half its maximum opening.

[0158] That is, when the outdoor ambient temperature Ta is low, the heat recovery effect will be poor, and even if the speed of the outdoor fan 10 is reduced, it will be difficult to achieve the required exhaust pressure, that is, the condensing pressure Pd; therefore, when the outdoor ambient temperature Ta is low, the openings of the first electronic expansion valve 4 and the second electronic expansion valve 5 are fixed at half of their maximum openings respectively to maintain the condensing pressure for normal operation of the unit system, and the condensing pressure is increased by adjusting the speed of the outdoor fan 10, thereby improving the heat recovery effect.

[0159] Of course, in the above stages, the wind speed of the outdoor fan 10 can be synchronously adjusted to accelerate the increase of the unit system condensing pressure Pd.

[0160] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0161] The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A multi-split air conditioner, characterized in that: Including the outdoor side, which includes: A compressor including an exhaust port and an intake port; an exhaust pressure sensor, which is used to detect the refrigerant pressure at the exhaust port, recorded as condensing pressure; A water-fluorine heat exchanger comprising a refrigerant passage and a water passage; one end of the refrigerant passage is connected to the exhaust port, and is used to exchange heat and condense the refrigerant passing through the refrigerant passage with the water passing through the water passage, thereby increasing the temperature of the water in the water passage; An outdoor heat exchanger, one end of which is connected to the exhaust port and is connected in parallel with the water-fluorine heat exchanger, for condensing the refrigerant during the refrigeration cycle; an outdoor fan, which is provided corresponding to the outdoor heat exchanger and is used to accelerate the flow of air inside and around the outdoor heat exchanger to accelerate heat exchange; An outlet water temperature sensor, used to obtain the outlet water temperature of the water-fluorine heat exchanger; a controller connected to the exhaust pressure sensor, the outdoor fan, and the outlet water temperature sensor, configured with a hot water mode, and in the hot water mode, receiving the outlet water temperature and the condensing pressure, and setting a first hot water target condensing pressure according to the outlet water temperature; and controlling the outdoor fan speed to increase or decrease so that the condensing pressure is controlled near the first hot water target condensing pressure; It also includes a heat dissipation module and an electrical system; the heat dissipation module dissipates heat for the electrical system; the outdoor fan dissipates heat for the heat dissipation module; and the controller is included in the electrical system; It also includes a temperature acquisition module, which is electrically connected to the controller and is used to obtain the temperature of the controller, recorded as the control temperature, and transmit it to the controller; The controller is further configured with a first condensing pressure correction value, a second condensing pressure correction value greater than the first condensing pressure correction value, a first control temperature threshold, and a second control temperature threshold greater than the first control temperature threshold; The configuration of the controller also includes: The first hot water target condensing pressure is corrected by subtracting the first condensing pressure correction value, and the first hot water target condensing pressure is corrected by subtracting the second condensing pressure correction value; In the hot water mode, the controller receives the control temperature; when the control temperature reaches below the first control temperature threshold, the first hot water target condensing pressure is corrected by subtracting the first condensing pressure correction value; when the first hot water target condensing pressure is corrected by subtracting the first condensing pressure correction value and the control temperature reaches or exceeds the second control temperature threshold, the correction is switched to the first hot water target condensing pressure subtracting the second condensing pressure correction value.

2. The multi-split air conditioner according to claim 1, characterized in that: The controller is also configured with a no hot water demand mode and a no hot water target condensing pressure; The controller is further configured to receive the condensing pressure in the no-hot water demand mode, and control the outdoor fan speed to increase or decrease so that the condensing pressure is controlled near the no-hot water target condensing pressure.

3. The multi-split air conditioner according to claim 2, characterized in that: The controller is also configured with a first hot water temperature correction value; The first hot water target condensing pressure is equal to the refrigerant saturation pressure corresponding to the sum of the outlet water temperature and the first hot water temperature correction value.

4. The multi-split air conditioner according to claim 3, characterized in that: The configuration of the controller also includes: When the control temperature reaches the second control temperature threshold or above, the first hot water target condensing pressure is corrected by subtracting the second condensing pressure correction value; when the first hot water target condensing pressure is corrected by subtracting the second condensing pressure correction value and the control temperature reaches the first control temperature threshold or below, the correction is switched to the first hot water target condensing pressure subtracting the first condensing pressure correction value.

5. The multi-split air conditioner according to claim 4, characterized in that: The configuration of the controller also includes: Set the condensing pressure allowable threshold; When the first hot water target condensing pressure reaches or exceeds the maximum value of the condensing pressure allowable threshold, the first hot water target condensing pressure is equal to the maximum value of the set condensing pressure allowable threshold; When the first hot water target condensing pressure reaches or is below the minimum value of the condensing pressure allowable threshold, the first hot water target condensing pressure is equal to the minimum value of the set condensing pressure allowable threshold.

6. The multi-split air conditioner according to claim 5, characterized in that: The configuration of the controller further includes: in the hot water mode, when the first hot water target condensing pressure does not exceed the no hot water target condensing pressure, the first hot water target condensing pressure is equal to the no hot water target condensing pressure.

7. The multi-split air conditioner according to any one of claims 1 to 6, characterized in that: The first condensing pressure correction value is 0 MPa; the second condensing pressure correction value is 0.3 MPa; the first control temperature threshold is 63° C., and the second control temperature threshold is 65° C.

8. The multi-split air conditioner according to claim 5 or 6, characterized in that: The set condensing pressure allowable threshold is between 2.4 MPa and 3.4 MPa.

9. The multi-split air conditioner according to any one of claims 3 to 6, characterized in that: It also includes a hot water temperature setting module, which is in communication with the controller and is used to set the hot water temperature and transmit it to the controller; The controller is further configured with a second hot water temperature correction value, a second hot water target condensing pressure, and a third hot water target condensing pressure; the controller is further configured with: The second hot water target condensing pressure is equal to the refrigerant saturation pressure corresponding to the sum of the hot water temperature and the second hot water temperature correction value; The third hot water target condensing pressure is equal to the refrigerant saturation pressure corresponding to the hot water temperature; In the hot water mode, the compressor control mode includes a frequency increase control mode, a frequency decrease control mode, and a frequency maintenance operation mode; When the condensing pressure reaches or is lower than the smaller of the first hot water target condensing pressure and the third hot water target condensing pressure, the compressor operates in the frequency-increasing control mode; when the condensing pressure reaches or is higher than the larger of the first hot water target condensing pressure and the third hot water target condensing pressure while the compressor is in the frequency-increasing control mode, the compressor switches to the frequency-maintaining operation mode. When the condensing pressure reaches or exceeds the second hot water target condensing pressure, the compressor operates in the frequency reduction control mode; when the compressor is in the frequency reduction control mode and the condensing pressure reaches or exceeds the larger of the first hot water target condensing pressure and the third hot water target condensing pressure, the compressor switches to the frequency maintenance operation mode; When the compressor is in the frequency maintaining operation mode and the condensing pressure reaches the second hot water target condensing pressure or above, the compressor switches to the frequency reduction control mode; when the condensing pressure reaches the smaller of the first hot water target condensing pressure and the third hot water target condensing pressure or below, the compressor switches to the frequency increase control mode.

10. The multi-split air conditioner according to claim 9, characterized in that: The first hot water temperature correction value and the second hot water temperature correction value are both 6°C.

Images