Outdoor unit for water source multi-split system, control method thereof, and water source multi-split system

Abstract

The outdoor unit for a water source multi-connected unit, a control method thereof and the water source multi-connected unit are provided in the present disclosure, and relate to the technical field of multi-connected units, wherein the outdoor unit comprises a compressor, a first stop valve, a reversing valve and a first heat exchanger unit. The compressor has a suction port and a discharge port. The first interface of the reversing valve is coupled with the discharge port. The first port of the first heat exchanger is coupled with the second interface of the reversing valve, and the second port is coupled with the first stop valve. The second branch parallel to the first branch where the first heat exchanger is located is provided with a first throttling element. In the cooling mode, when the discharge pressure of the compressor is less than a first threshold value, the first throttling element is in an open state. In the heating mode, when the suction pressure of the compressor is greater than a second threshold value, the first throttling element is in the open state. The outdoor unit can intelligently adjust the state of the first throttling element based on the discharge pressure and the suction pressure of the compressor to cope with extreme water temperature working conditions.

Description

Technical Field

[0001] This disclosure belongs to the field of multi-split air conditioning technology, specifically relating to an outdoor unit for a water source multi-split air conditioning system and its control method, and the water source multi-split air conditioning system. Background Technology

[0002] Most water source multi-split air conditioning units in related technologies are installed in enclosed spaces. Due to the large heat dissipation of the machine itself, additional ventilation and heat dissipation equipment is required, which increases the initial investment cost.

[0003] In related technologies, water-source multi-split air conditioning systems are prone to instability and shutdowns under extreme water temperature conditions due to the mismatch between evaporation and condensation heat. Specifically, in cooling mode, if the temperature of the refrigerant circulating to the indoor units is too low, the indoor units will experience low pressure or even trigger anti-freeze protection, resulting in shutdown. Conversely, in heating mode, if the temperature of the refrigerant circulating to the indoor units is too high, the indoor units will experience high low pressure or even trigger high pressure protection, resulting in shutdown. Summary of the Invention

[0004] This disclosure provides an outdoor unit for a water-source multi-split air conditioner and its control method, aiming to at least partially solve the technical problem of unstable operation of multi-split air conditioners caused by insufficient consideration of the heat mismatch between evaporation and condensation under extreme water temperature conditions.

[0005] At least one embodiment of this disclosure provides an outdoor unit for a multi-split air conditioning system, comprising:

[0006] The compressor has an intake port and an exhaust port;

[0007] First shut-off valve;

[0008] A reversing valve having a first port and a second port, the first port being connected to the exhaust port; and...

[0009] A first heat exchanger has a first port and a second port, the first port being connected to the second interface of the reversing valve and the second port being connected to the first shut-off valve.

[0010] The second branch, which is connected in parallel with the first branch where the first heat exchanger is located, is provided with a first throttling element. One end of the second branch is provided in the connecting pipe between the reversing valve and the first heat exchanger, and the other end of the second branch is provided in the connecting pipe between the second port of the first heat exchanger and the first shut-off valve.

[0011] In cooling mode, the first throttling element is in the open state when the compressor's discharge pressure is less than a first threshold; in heating mode, the first throttling element is in the open state when the compressor's suction pressure is greater than a second threshold.

[0012] The outdoor unit provided in at least one embodiment of this disclosure further includes:

[0013] A refrigerant radiator is provided in the third branch, which is connected in parallel with the connecting pipe between the second port of the first heat exchanger and the first shut-off valve. The refrigerant radiator is used to dissipate heat from the circuit board of the water source multi-split unit.

[0014] In the outdoor unit provided in at least one embodiment of this disclosure, the first branch is further provided with a second throttling element; and the second throttling element is connected in series with the first heat exchanger.

[0015] In the outdoor unit provided in at least one embodiment of this disclosure, the third branch where the refrigerant radiator is located is further provided with a third throttling element connected in series with the refrigerant radiator;

[0016] The connecting pipeline between the second port of the first heat exchanger and the first shut-off valve is provided with a fourth throttling element as a fourth branch, and the fourth throttling element is connected to the second throttling element.

[0017] The outdoor unit provided in at least one embodiment of this disclosure further includes:

[0018] A first bypass branch is provided between the compressor and the refrigerant radiator. The first bypass branch is provided with a solenoid valve and a first check valve connected in series with the solenoid valve. The solenoid valve is connected to the exhaust port of the compressor, and the first check valve is connected to the refrigerant radiator.

[0019] The outdoor unit provided in at least one embodiment of this disclosure further includes:

[0020] A second heat exchanger is connected to the second port of the first heat exchanger; and

[0021] The second bypass branch has one end connected to the connecting pipe between the second heat exchanger and the second port of the first heat exchanger. After passing through the fifth throttling element and the second heat exchanger, the other end of the second bypass branch is connected to the suction port of the compressor.

[0022] At least one embodiment of this disclosure also provides a method for controlling an outdoor unit of a water source multi-split air conditioning system, the outdoor unit including a compressor, a reversing valve, and a first heat exchanger, the method comprising:

[0023] Upon receiving a command to activate cooling mode, the device enters cooling mode.

[0024] The high-temperature, high-pressure gaseous refrigerant discharged from the compressor enters the first heat exchanger through the reversing valve, and then enters the indoor unit of the water source multi-split system.

[0025] When the compressor's discharge pressure is lower than the first threshold, the amount of refrigerant flowing through the first branch where the first heat exchanger is located is reduced, and the second branch connected in parallel with the first branch where the first heat exchanger is located is opened, so that the refrigerant flows through the second branch.

[0026] The method provided in at least one embodiment of this disclosure further includes:

[0027] Upon receiving a command to activate heating mode, the device enters heating mode.

[0028] The high-temperature, high-pressure gaseous refrigerant discharged from the compressor enters the indoor unit of the water source multi-split system through the reversing valve and then enters the first heat exchanger.

[0029] When the compressor's suction pressure is higher than the second threshold, the amount of refrigerant flowing through the first branch where the first heat exchanger is located is reduced, and the second branch connected in parallel with the first branch where the first heat exchanger is located is opened, so that the refrigerant flows through the second branch.

[0030] In at least one embodiment of the method provided in this disclosure, the outdoor unit includes a refrigerant radiator.

[0031] The refrigerant flowing through the first branch and / or the second branch flows through the third branch where the refrigerant radiator is located and the fourth branch connected in parallel with the third branch.

[0032] When the water temperature of the first heat exchanger is lower than the adjustable limit of the first branch and / or the second branch, the high-temperature and high-pressure gaseous refrigerant discharged by the compressor flows into the third branch through the fifth branch, thereby increasing the operating temperature of the refrigerant radiator.

[0033] The method provided in at least one embodiment of this disclosure further includes:

[0034] When the indoor unit's operating load is less than the threshold, a portion of the refrigerant flowing through the fourth branch is bypassed and flows into the sixth branch.

[0035] In at least one embodiment of the method provided in this disclosure, the outdoor unit includes a refrigerant radiator.

[0036] The refrigerant flowing through the third branch where the refrigerant radiator is located and / or the fourth branch connected in parallel with the third branch flows through the first branch and the second branch.

[0037] When the water temperature of the first heat exchanger is lower than the adjustable limit of the first branch and / or the second branch, the high-temperature and high-pressure gaseous refrigerant discharged by the compressor flows into the third branch through the fifth branch, thereby increasing the operating temperature of the refrigerant radiator.

[0038] The method provided in at least one embodiment of this disclosure further includes:

[0039] As the water temperature in the first heat exchanger gradually increases, the amount of refrigerant in the first branch is gradually reduced, while the amount of refrigerant in the second branch is increased simultaneously.

[0040] In at least one embodiment of the method provided in this disclosure, the outdoor unit further includes a first shut-off valve. The high-temperature, high-pressure gaseous refrigerant discharged from the compressor enters the first heat exchanger via a reversing valve and then enters the indoor unit via the first shut-off valve. The method further includes:

[0041] After the amount of refrigerant flowing through the first branch where the first heat exchanger is located decreases, the liquid subcooling at the location of the first shut-off valve is obtained. When the liquid subcooling is identified as being greater than a preset subcooling threshold, the amount of refrigerant flowing through the second branch is increased.

[0042] The method provided in at least one embodiment of this disclosure further includes:

[0043] When the compressor's discharge pressure is not lower than the first threshold, the compressor's suction pressure is obtained, and when the suction pressure is less than a preset suction pressure threshold, the refrigerant flow rate of the sixth branch is increased.

[0044] In at least one embodiment of the method provided in this disclosure, the outdoor unit further includes a third throttling element disposed on the third branch, and the method further includes:

[0045] Obtain the refrigerant heat dissipation temperature of the refrigerant radiator;

[0046] When the refrigerant heat dissipation temperature is less than the first temperature threshold, the opening degree of the third throttling element is obtained. If the opening degree of the third throttling element is not found to be at its minimum value, the opening degree of the third throttling element is reduced. If the opening degree of the third throttling element is found to be at its minimum value, the high-temperature and high-pressure gaseous refrigerant discharged by the compressor flows into the refrigerant radiator through the fifth branch.

[0047] When the refrigerant heat dissipation temperature is not less than a first temperature threshold, the refrigerant heat dissipation temperature is identified as being greater than a second temperature threshold, causing the refrigerant flow rate of the third branch to increase while the refrigerant flow rate of the fourth branch to decrease; and when the refrigerant heat dissipation temperature is identified as being less than a second temperature threshold, the refrigerant flow rates of the third branch and the fourth branch remain unchanged, wherein the second temperature threshold is greater than the first temperature threshold.

[0048] In at least one embodiment of the method provided in this disclosure, the outdoor unit further includes a second shut-off valve, wherein the high-temperature, high-pressure gaseous refrigerant discharged from the indoor unit compressor sequentially passes through a reversing valve and the second shut-off valve into the indoor unit, and the method further includes:

[0049] After reducing the amount of refrigerant flowing through the first branch where the first heat exchanger is located, the exhaust temperature of the compressor is obtained. When the exhaust temperature is greater than a preset superheat threshold, the amount of refrigerant flowing through the second branch is increased. When the exhaust temperature is not greater than the preset superheat threshold, the amount of refrigerant flowing through the third branch is reduced.

[0050] The method provided in at least one embodiment of this disclosure further includes:

[0051] When the compressor's suction pressure is not higher than the second threshold, the compressor's discharge pressure is obtained. When the discharge pressure is greater than the preset discharge pressure threshold, the refrigerant flow rates of the third and fourth branches are increased simultaneously. When the discharge pressure is not greater than the preset discharge pressure threshold, the refrigerant flow rates of the third and fourth branches remain unchanged.

[0052] At least one embodiment of this disclosure also provides a water-source multi-split air conditioner, the water-source multi-split air conditioner comprising an indoor unit and an outdoor unit as provided in any embodiment of this disclosure, wherein...

[0053] The indoor unit includes multiple indoor units connected to the outdoor unit of the water source multi-split system.

[0054] The outdoor unit and control method for a water-source multi-split air conditioning system provided in this disclosure, along with the water-source multi-split air conditioning system itself, utilize water as a heat source and feature strong heat exchange capacity and a wide water temperature range. This outdoor unit can intelligently adjust the state of the first throttling element based on the compressor's discharge and suction pressures to cope with extreme water temperature conditions. By limiting the compressor's discharge pressure in cooling mode and suction pressure in heating mode, and intelligently adjusting the refrigerant flow rate, the amount of refrigerant flowing through different branches is automatically adjusted according to the actual operating conditions to achieve the desired heat exchange effect and energy efficiency ratio, effectively improving heat exchange efficiency and enabling the water-source multi-split air conditioning system to operate stably under extreme conditions. Furthermore, this outdoor unit and its control method also possess high stability and reliability, ensuring stable operation under various conditions and providing users with a more comfortable and energy-efficient user experience.

[0055] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0056] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0057] Figure 1 A schematic diagram of an outdoor unit provided for at least one embodiment of this disclosure;

[0058] Figure 2 A schematic diagram of another outdoor unit provided for at least one embodiment of this disclosure;

[0059] Figure 3 A schematic diagram of a temperature control scheme for a water-cooled heat exchanger provided in at least one embodiment of this disclosure;

[0060] Figure 4 A schematic diagram of a temperature control scheme for a refrigerant radiator provided in at least one embodiment of this disclosure;

[0061] Figure 5 A schematic diagram of yet another outdoor unit provided for at least one embodiment of this disclosure;

[0062] Figure 6 A schematic diagram of yet another outdoor unit provided for at least one embodiment of this disclosure;

[0063] Figure 7 A schematic diagram of yet another outdoor unit provided for at least one embodiment of this disclosure;

[0064] Figure 8 A schematic diagram of an outdoor unit example provided for at least one embodiment of this disclosure;

[0065] Figure 9 A schematic diagram of the refrigerant flow direction in the cooling process of an outdoor unit example provided for at least one embodiment of this disclosure;

[0066] Figure 10 A schematic diagram of the refrigerant flow direction during the heating process of an outdoor unit example provided in at least one embodiment of this disclosure;

[0067] Figure 11 A schematic diagram of another outdoor unit example provided for at least one embodiment of this disclosure;

[0068] Figure 12 A flowchart illustrating a control method provided in at least one embodiment of this disclosure;

[0069] Figure 13 A flowchart illustrating another control method provided for at least one embodiment of this disclosure;

[0070] Figure 14 A schematic diagram illustrating an example of a refrigerant heat dissipation control process in a refrigeration process, provided for at least one embodiment of this disclosure;

[0071] Figure 15 A schematic diagram illustrating an example of a low-water-temperature heating control process in a refrigeration process provided for at least one embodiment of this disclosure;

[0072] Figure 16 A schematic diagram illustrating an example of a refrigerant heat dissipation control process during heating, provided for at least one embodiment of this disclosure;

[0073] Figure 17 A flowchart illustrating an example of high-temperature heating control in a heating process provided for at least one embodiment of this disclosure;

[0074] Figure 18 A structural block diagram of a water source multi-unit system provided in at least one embodiment of this disclosure.

[0075] Figure Labels

[0076] 10-Outdoor unit; 100-Compressor; 200-Reversing valve; 201-First four-way valve; 202-Second four-way valve; 300-First heat exchanger; 301-Water-cooled heat exchanger; 302-First throttling element; 303-Second throttling element; 400-Refrigerant radiator; 401-Third throttling element; 402-Fourth throttling element; 500-First bypass branch; 501-Solenoid valve; 502-First check valve; 600-The Two heat exchangers; 601-Fifth throttling element; 700-Gas-liquid separator; 801-First shut-off valve; 802-Second shut-off valve; 803-Third shut-off valve; 804-Second check valve; T_finA-First temperature threshold; T_finB-Second temperature threshold; Ps_A-Second threshold; Pd_A-Discharge pressure threshold; Pd_A2-First threshold; Ps_B-Intake pressure threshold; Tsc_A-Subcooling threshold; Td_A-Superheating threshold. Detailed Implementation

[0077] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be particularly noted that the following embodiments are for illustrative purposes only and do not limit the scope of the application. Similarly, the following embodiments are only some, not all, embodiments of the present application, and all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present application.

[0078] The terms "first," "second," and "third" used in the embodiments of this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first," "second," and "third" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two and three, unless otherwise explicitly specified.

[0079] The terms "comprising" and "having," and any variations thereof, used in the embodiments of this application, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or components inherent to such processes, methods, products, or devices.

[0080] In this disclosure, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0081] In this disclosure, the term "liquid-stop subcooling" refers to the degree of subcooling of the refrigerant at the shut-off valve, i.e., the extent to which the refrigerant temperature is lower than its corresponding saturated evaporation temperature. By controlling the liquid-stop subcooling, the energy efficiency of the refrigeration system can be optimized, the refrigeration effect improved, and the stable operation of the system ensured.

[0082] In the embodiments of this disclosure, the term "superheat" refers to the superheat of the refrigerant at the shut-off valve.

[0083] In the embodiments of this disclosure, the term "heating power" refers to the amount of heat provided by the air conditioning system to the room per unit time, measured in watts or kilowatts.

[0084] In this disclosure, the term "water temperature" refers to a key parameter that affects the heating performance of a heat pump or central air conditioning system. Generally, the higher the water temperature, the stronger the heating capacity.

[0085] In the embodiments of this disclosure, the term "exhaust pressure" refers to the air pressure at the exhaust port of the compressor.

[0086] In this disclosure, the term "suction pressure" refers to the air pressure at the suction port of the compressor.

[0087] In this disclosure, the term "refrigerant heat dissipation temperature" refers to the temperature of the refrigerant at the refrigerant radiator. By precisely controlling the refrigerant heat dissipation temperature, the energy efficiency of the refrigeration system can be further optimized, energy consumption reduced, and the overall performance of the system improved.

[0088] In this disclosure, the term "operating temperature of the refrigerant radiator" refers to the temperature reached by the refrigerant radiator under normal operating conditions. By monitoring and controlling the operating temperature of the refrigerant radiator, it can be ensured that it operates under suitable conditions, thereby avoiding overheating or overcooling, further extending the service life of the refrigerant radiator, optimizing the cooling or heating effect, and improving the energy efficiency of the entire system.

[0089] Figure 1 This is a schematic diagram of an outdoor unit provided for at least one embodiment of this disclosure. Figure 1 As shown, the outdoor unit 10 includes a compressor 100, a first shut-off valve 801, a reversing valve 200, and a first heat exchanger 300.

[0090] The compressor 100 has an intake port and an exhaust port.

[0091] The reversing valve 200 has a first interface and a second interface, the first interface being connected to the exhaust port.

[0092] The first heat exchanger 300 has a first port and a second port. The first port is connected to the second interface of the reversing valve 200, and the second port is connected to the first shut-off valve 801.

[0093] The first heat exchanger 300 can be a water-cooled heat exchanger or an air-cooled heat exchanger. In this embodiment, a water-cooled heat exchanger 301 is used as an example of the first heat exchanger 300, but it is not intended to limit the first heat exchanger to a water-cooled heat exchanger. In this embodiment, the first shut-off valve is a liquid-side shut-off valve.

[0094] The second branch, which is connected in parallel with the first branch where the water-cooled heat exchanger 301 is located, is provided with a first throttling element 302. One end of the second branch is provided in the connecting pipe between the reversing valve 200 and the water-cooled heat exchanger 301, and the other end of the second branch is provided in the connecting pipe between the second port of the water-cooled heat exchanger 301 and the first shut-off valve 801.

[0095] In cooling mode, when the discharge pressure of compressor 100 is less than the first threshold Pd_A2, the first throttling element 302 is in the open state. In heating mode, when the suction pressure of compressor 100 is greater than the second threshold Pd_A2, the first throttling element 302 is in the open state.

[0096] It should be noted that the second port of the reversing valve 200 is used to directly or indirectly connect to the indoor unit of the water source multi-split system. The compressor 100 is used to provide high-temperature, high-pressure gas, and its suction port can be connected in various ways, such as directly to the refrigerant in the indoor unit or through other components (such as another reversing valve). The embodiments of this disclosure do not limit this. The reversing valve 200 is used to switch the refrigerant flow direction between the cooling and heating processes. The other ports of the reversing valve 200 can also be connected in various ways, such as the third port directly connecting to the indoor unit or through other components. The embodiments of this disclosure do not limit this either. The water-cooled heat exchanger 301 is used to achieve heat exchange between the refrigerant and water, possessing high-efficiency heat exchange performance. Simultaneously, the parallel connection of the first and second branches allows the water source multi-split system to automatically adjust the refrigerant flow direction and flow rate under different water temperature conditions to achieve the desired heat exchange effect.

[0097] In implementation, during cooling mode, if the discharge pressure of compressor 100 is less than the first threshold Pd_A2, the refrigerant temperature output by water-cooled heat exchanger 301 may be too low. Opening the first throttling element 302 and increasing the amount of high-temperature refrigerant can raise the refrigerant temperature output by water-cooled heat exchanger 301. During heating mode, if the suction pressure of compressor 100 is greater than the second threshold, opening the first throttling element 302 helps to reduce the suction pressure of compressor 100.

[0098] Some embodiments of this disclosure also provide control methods and water source multi-split systems corresponding to the outdoor unit described above.

[0099] The outdoor unit provided by at least one embodiment of this disclosure is applicable to any existing water source multi-split air conditioning application scenario, and exhibits excellent performance, especially in application scenarios that require efficient use of water source for cooling or heating.

[0100] Compared to related technologies, the outdoor unit provided by at least one embodiment of this disclosure, using water as a heat source, features strong heat exchange capacity and a wide water temperature range. This outdoor unit 10 can intelligently adjust the state of the first throttling element 302 based on the discharge and suction pressures of the compressor 100 to cope with extreme water temperature conditions. By limiting the discharge pressure of the compressor 100 in cooling mode and the suction pressure of the compressor 100 in heating mode, and intelligently adjusting the refrigerant flow, the amount of refrigerant flowing through different branches is automatically adjusted according to the actual operating conditions to achieve the desired heat exchange effect and energy efficiency ratio, effectively improving heat exchange efficiency and enabling the water source multi-split system to operate stably under extreme conditions. Furthermore, this outdoor unit and its control method also possess high stability and reliability, ensuring stable operation under various conditions and providing users with a more comfortable and energy-saving user experience.

[0101] Figure 2 This is a schematic diagram of another outdoor unit provided for at least one embodiment of this disclosure. (See diagram below.) Figure 2 As shown, to ensure effective heat dissipation of the circuit board in the indoor unit, the outdoor unit also includes a refrigerant radiator 400. The refrigerant radiator is located on a third branch, which is connected in parallel to the connecting pipe between the second port of the first heat exchanger 300 and the first shut-off valve 801. The second port of the first heat exchanger 300 is connected to the refrigerant radiator 400, which is used to dissipate heat from the circuit board of the water-source multi-split unit. Under specific operating conditions, such as when the circuit board temperature exceeds a preset safety threshold, the amount of refrigerant flowing through the refrigerant radiator 400 can be increased to improve heat dissipation efficiency and ensure stable operation of the indoor unit.

[0102] Figure 3 A schematic diagram of a temperature control scheme for a water-cooled heat exchanger provided in at least one embodiment of this disclosure. (See diagram for example.) Figure 3 As shown, to better control the temperature of the first heat exchanger 300, a second throttling element 303 is also provided in the first branch, which is connected in series with the water-cooled heat exchanger 301. By setting the second throttling element 303, the amount of refrigerant flowing through the water-cooled heat exchanger 301 can be intelligently adjusted according to the actual operating conditions of the first heat exchanger 300, thereby achieving precise temperature control of the water-cooled heat exchanger 301. This design not only improves heat exchange efficiency but also ensures the stable operation of the water-cooled heat exchanger 301 under various operating conditions, further enhancing the overall performance and energy efficiency ratio of the water source multi-split system.

[0103] Figure 4 This is a schematic diagram of a temperature control scheme for a refrigerant radiator provided in at least one embodiment of this disclosure. Figure 4As shown, to improve the temperature control effect of the refrigerant radiator 400, a third throttling element 401 connected in series with the refrigerant radiator 400 is also provided in the third branch. One end of the third throttling element 401 is connected to the second port of the first heat exchanger 300, and the other end is used to connect to the indoor unit of the water source multi-split system. The connecting pipe between the second port of the first heat exchanger 300 and the first shut-off valve 801 is provided with a fourth throttling element 402 as a fourth branch. One end of the fourth throttling element 402 is connected to the second port of the first heat exchanger 300 via the second throttling element, and the other end is used to connect to the indoor unit of the water source multi-split system. In the temperature control scheme of the refrigerant radiator 400, the setting of the third throttling element 401 and the fourth throttling element 402 enables the refrigerant radiator 400 to intelligently adjust the refrigerant flow rate according to the heat dissipation requirements of the operating circuit board. When the circuit board has a high refrigerant demand, the third throttling element 401 can appropriately increase its opening, allowing more refrigerant to flow through the refrigerant radiator 400 for heat dissipation, while the fourth throttling element 402 correspondingly decreases its opening to balance the refrigerant distribution. Conversely, when the circuit board has a low refrigerant demand, the third throttling element 401 will decrease its opening, while the fourth throttling element 402 will increase its opening. This parallel branch design not only improves the heat dissipation efficiency of the refrigerant radiator 400 but also enhances the system's flexibility and stability, ensuring that the water source multi-split unit maintains efficient and stable operation under various working conditions.

[0104] Typically, the compressor, reversing valve, first heat exchanger, and liquid-side shut-off valve are connected via refrigerant piping in the order of refrigerant flow to form the main circuit. In this embodiment, the first branch and the fourth branch are part of the main circuit.

[0105] Figure 5 This is a schematic diagram of yet another outdoor unit provided for at least one embodiment of this disclosure. (See diagram below.) Figure 5As shown, to further prevent the refrigerant radiator 400 from malfunctioning under cooling conditions, the outdoor unit also includes a first bypass branch 500 located between the compressor 100 and the refrigerant radiator. This first bypass branch 500 is equipped with a solenoid valve 501 and a first one-way valve 502 connected in series with the solenoid valve 501. The solenoid valve 501 is connected to the exhaust port of the compressor 100, and the first one-way valve 502 is connected to the refrigerant radiator 400. Under cooling conditions, if the refrigerant heat dissipation temperature of the refrigerant radiator 400 is too low, it may affect the operation of the circuit board, causing the indoor unit to experience low pressure or even trigger anti-freeze protection and shut down. The first bypass branch 500 is designed to provide an emergency measure to deal with such sudden situations. When the refrigerant heat dissipation temperature of the refrigerant radiator 400 is too low, by controlling the opening of the solenoid valve 501, the high-temperature, high-pressure refrigerant discharged from the compressor 100 can be directly introduced into the first bypass branch 500. At this point, the first one-way valve 502 ensures that the refrigerant can only flow in one direction, preventing backflow and damage to the system. The first bypass branch 500 utilizes the heat from the high-temperature, high-pressure refrigerant to raise the refrigerant temperature in the refrigerant radiator 400, preventing the indoor unit from experiencing low pressure or even triggering anti-freeze protection and shutting down. This design not only improves the system's reliability and stability but also provides users with a safer and more reliable user experience.

[0106] Figure 6 This is a schematic diagram of yet another outdoor unit provided for at least one embodiment of this disclosure. (See diagram below.) Figure 6 As shown, in Figure 1 Based on this, to further improve the performance of the outdoor unit, the outdoor unit also includes a second heat exchanger 600 and a second bypass branch. In this embodiment, the second heat exchanger can be a subcooler. One end of the second heat exchanger 600 is connected to the second port of the first heat exchanger 300, and the other end is used to connect to the indoor unit of the water source multi-split system. One end of the second bypass branch is connected to the connecting pipe between the second heat exchanger 600 and the second port of the first heat exchanger. After passing through the fifth throttling element 601 and the second heat exchanger 600, the other end of the second bypass branch is connected to the suction port of the compressor 100. Under cooling or heating conditions, the operating mechanism of the second heat exchanger 600 further optimizes the system performance. Specifically, in summer cooling conditions, the refrigerant flows from the second port of the first heat exchanger 300 and then through the second heat exchanger, continuing to transfer the heat of the refrigerant to the indoor unit of the water source multi-split system, thereby achieving indoor cooling. The second bypass branch regulates the refrigerant flow through the fifth throttling element 601 and the second heat exchanger, introducing a portion of the refrigerant into the suction port of the compressor 100. This design not only improves the refrigerant's thermal utilization efficiency but also enhances the system's flexibility and adaptability. Under different operating conditions, the second heat exchanger 600 can adjust the refrigerant's flow path and flow rate according to actual needs, thereby ensuring the efficient and stable operation of the entire water source multi-split system.

[0107] Figure 7 This is a schematic diagram of yet another outdoor unit provided for at least one embodiment of this disclosure. (See diagram below.) Figure 7 As shown, in Figure 6 Building upon this foundation, to optimize the refrigerant circulation process, the outdoor unit also includes a gas-liquid separator 700. The gas-liquid separator 700 is connected to the suction port of the compressor 100, and the other end of the second bypass branch also connects to the suction port of the compressor 100 via the gas-liquid separator 700. The gas-liquid separator 700 further optimizes the refrigerant circulation process. Specifically, when the refrigerant in the second bypass branch flows through the gas-liquid separator 700, it effectively separates the gas and liquid components in the refrigerant. This ensures that the refrigerant entering the suction port of the compressor 100 is primarily gaseous, preventing potential damage or efficiency reduction caused by liquid refrigerant directly entering the compressor 100. Simultaneously, the gas-liquid separator 700 ensures that the refrigerant drawn into the compressor 100 has more stable pressure and temperature, further enhancing the system's stability and reliability. This design not only improves the overall system performance but also extends the compressor's lifespan, providing users with a more durable and efficient user experience.

[0108] In some embodiments, the reversing valve 200 includes a single four-way valve, and the outdoor unit further includes a first shut-off valve 801, a second shut-off valve 802, and a second check valve 804. The first shut-off valve 801 is located on the refrigerant line between the third port of the reversing valve 200 and the indoor unit; the second shut-off valve 802 is located on the refrigerant line between the other end of the second heat exchanger 600 and the indoor unit; and the second check valve 804 is located at the compressor's discharge port.

[0109] In other embodiments, the reversing valve 200 includes a first four-way valve 201 and a second four-way valve 202. The outdoor unit also includes a first shut-off valve 801, a second shut-off valve 802, a third shut-off valve 803, and a second check valve 804. The third shut-off valve 803 is disposed on the refrigerant pipeline between the fourth port of the reversing valve 200 and the indoor unit.

[0110] The first shut-off valve 801 provides additional safety protection. Even if the water-cooled heat exchanger 301 malfunctions or requires maintenance, the flow of refrigerant can be cut off by closing the first shut-off valve 801, ensuring that the indoor unit is not affected and improving the reliability and flexibility of the entire refrigeration system.

[0111] In some embodiments, Figure 7 In addition, the outdoor unit also includes a controller that performs all the steps in the subsequent method embodiments.

[0112] Furthermore, this outdoor unit features intelligent diagnostics. Built-in sensors monitor the system's operating status in real time, including key parameters such as refrigerant pressure, temperature, and flow rate. Upon detecting anomalies, such as refrigerant leaks or compressor overheating, the intelligent diagnostics system immediately triggers an alarm mechanism and transmits fault information to a remote monitoring center via wireless communication. This allows technicians to quickly locate and resolve the problem, significantly reducing downtime and improving system maintenance efficiency and operational stability. Simultaneously, the outdoor unit also features remote upgrade capabilities via connection to the controller. It receives upgrade commands from the remote monitoring center through the wireless communication module, automatically downloading and installing the latest software or firmware to ensure the system always remains in the desired state.

[0113] Figure 8 This is a schematic diagram of an outdoor unit example provided for at least one embodiment of this disclosure. For example... Figure 8 As shown, the reversing valve 200 includes a first four-way valve 201. Port C (condenser port) of the first four-way valve 201 serves as the second interface of the reversing valve 200, port D (exhaust port) serves as the first interface, port E (evaporator port) serves as the third interface, and port S (suction port) serves as the fourth interface. The refrigerant flow direction in the refrigeration process is as follows... Figure 9 As shown, the refrigerant flow direction during the heating process is as follows: Figure 10 As shown.

[0114] During summer cooling, the first four-way valve 201 is closed, the fourth throttling element 402 is fully open, and the refrigerant enters the outdoor unit 10 through the second shut-off valve 802, and then enters the indoor unit from the outdoor unit 10 through the first shut-off valve 801.

[0115] When the water temperature of the water-cooled heat exchanger 301 is high and the discharge pressure of the compressor 100 is within the acceptable range (above 1.9MPa), the fourth throttling element 402 and the second throttling element 303 are fully open. When the water temperature decreases and the discharge pressure of the compressor 100 decreases, the second throttling element 303 gradually closes to increase the discharge pressure, while the first throttling element 302 gradually opens.

[0116] When the extremely low water temperature exceeds the adjustment limit of the second throttling element 303 / the first throttling element 302, the solenoid valve 501 is opened to improve the heat dissipation of the refrigerant and prevent condensation.

[0117] When the indoor unit is under low load, in order to prevent the indoor unit from shutting down due to excessive refrigerant flow, the fifth throttling element 601 is opened to bypass part of the refrigerant and reduce the refrigerant flow through the indoor unit.

[0118] During winter heating, the first four-way valve 201 opens, and the fourth throttling element 402 mainly throttles the refrigerant. The refrigerant enters the indoor unit through the second shut-off valve 802 and then enters the outdoor unit 10 through the first shut-off valve 801. The third throttling element 401 throttles and controls the refrigerant flow through the refrigerant radiator 400. When a risk of condensation is detected in the refrigerant heat dissipation (the refrigerant heat dissipation temperature is less than the first temperature threshold T_finA), the third throttling element 401 will be continuously closed to reduce the refrigerant flow through the refrigerant radiator 400, thereby increasing the operating temperature of the refrigerant radiator 400.

[0119] If the refrigerant temperature continues to decrease after exceeding the adjustment range limit of the third throttling element 401 / fourth throttling element 402, the solenoid valve 501 will be opened to bypass the high-temperature exhaust gas from the compressor 100 and continue to reduce the refrigerant flow through the refrigerant radiator 400, thereby increasing the operating temperature of the refrigerant radiator 400.

[0120] As the water temperature in the water-cooled heat exchanger 301 gradually increases, the opening of the second throttling element 303 is gradually closed, slowly shifting the throttling position from the third throttling element 401 / fourth throttling element 402 to the second throttling element 303. Because the water temperature is high, the low-pressure area after heat exchange between the refrigerant and water is very high. At this point, the second throttling element 303 is gradually closed, while the first throttling element 302 is simultaneously opened, reducing the refrigerant flow rate through the water-cooled heat exchanger 301, reducing the heat exchange with water, and lowering the low-pressure area.

[0121] Figure 11 This is a schematic diagram of another outdoor unit example provided for at least one embodiment of this disclosure. (See diagram below.) Figure 11 As shown, the reversing valve includes a first four-way valve 201 and a second four-way valve 202. The C port (condensation port) of the second four-way valve 202 serves as the second interface of the reversing valve 200. The D port of the first four-way valve 201 and the D port (exhaust port) of the second four-way valve 202 are connected in parallel to serve as the first interface of the reversing valve 200. The E port (evaporation port) of the first four-way valve 201 serves as the third interface of the reversing valve 200. The S port of the first four-way valve 201 and the S port (intake port) of the second four-way valve 202 are connected in parallel to serve as the fourth interface of the reversing valve 200.

[0122] During summer cooling, the first four-way valve 201 and the second four-way valve 202 are closed, and the fourth throttling element 402 is fully open. The refrigerant enters the outdoor unit 10 through the second shut-off valve 802 and then enters the indoor unit from the outdoor unit 10 through the first shut-off valve 801.

[0123] When the water temperature of the water-cooled heat exchanger 301 is high and the discharge pressure of the compressor 100 is within the acceptable range (above 1.9MPa), the fourth throttling element 402 and the second throttling element 303 are fully open (no throttling, no flow adjustment). When the water temperature decreases and the discharge pressure of the compressor 100 decreases, the second throttling element 303 gradually closes to increase the discharge pressure, while the first throttling element 302 gradually opens.

[0124] When the extremely low water temperature exceeds the adjustment limit of the second throttling element 303 / the first throttling element 302, the solenoid valve 501 is opened to improve the heat dissipation of the refrigerant and prevent condensation.

[0125] When the indoor unit is under low load, in order to prevent the indoor unit from shutting down due to excessive refrigerant flow, the fifth throttling element 601 is opened to bypass part of the refrigerant and reduce the refrigerant flow through the indoor unit.

[0126] During winter heating, the first four-way valve 201 and the second four-way valve 202 are open, allowing refrigerant to enter the indoor unit through the second shut-off valve 802 and then enter the outdoor unit 10 through the first shut-off valve 801. The fourth throttling element 402 mainly throttles the refrigerant, while the third throttling element 401 simultaneously throttles and controls the refrigerant flow through the refrigerant radiator 400. When a risk of condensation is detected in the refrigerant heat dissipation (the refrigerant heat dissipation temperature is lower than the first temperature threshold T_finA), the third throttling element 401 will be continuously closed to reduce the refrigerant flow through the refrigerant radiator 400, thereby increasing the operating temperature of the refrigerant radiator 400.

[0127] If the refrigerant temperature continues to decrease after exceeding the adjustment range limit of the third throttling element 401 / fourth throttling element 402, the solenoid valve 501 will be opened to bypass the high-temperature exhaust gas from the compressor 100 and continue to reduce the refrigerant flow through the refrigerant radiator 400, thereby increasing the operating temperature of the refrigerant radiator 400.

[0128] As the water temperature in the water-cooled heat exchanger 301 gradually increases, the opening of the second throttling element 303 is gradually closed, slowly shifting the throttling position from the third throttling element 401 / fourth throttling element 402 to the second throttling element 303. Due to the high water temperature, the low-pressure after heat exchange between the refrigerant and water is very high. At this time, the second throttling element 303 is gradually closed, while the first throttling element 302 is opened simultaneously, reducing the refrigerant flow rate through the water-cooled heat exchanger 301, reducing the heat exchange with water, and lowering the low pressure.

[0129] In some embodiments, the refrigerant is R410A. R410A refrigerant has excellent thermal conductivity and environmentally friendly characteristics, effectively improving the system's cooling and heating efficiency. Simultaneously, R410A refrigerant also has a low global warming potential, helping to reduce environmental impact. By using R410A refrigerant, along with an optimized heat exchanger and compressor, the outdoor unit can achieve more efficient and environmentally friendly cooling and heating performance.

[0130] Compared with related technologies, the outdoor unit structure disclosed herein has the following advantages:

[0131] 1. A first throttling element is provided in the second branch connected in parallel with the first branch where the first heat exchanger is located, which improves the problem of excessively low discharge pressure of the low water temperature refrigeration compressor and excessively high suction pressure of the high water temperature heating compressor.

[0132] 2. By arranging a refrigerant radiator, the heat of the circuit board is carried away by the refrigerant, thus enabling the installation of a water source multi-split system in an enclosed space.

[0133] 3. To improve the condensation problem of the refrigerant radiator, a third throttling element is installed to control the refrigerant flow through the refrigerant radiator and control the operating temperature of the refrigerant radiator. A first bypass branch is installed to actively increase the operating temperature of the refrigerant radiator under extreme low water temperature conditions, thereby achieving the design of refrigerant heat dissipation and anti-condensation.

[0134] Figure 12 This is a schematic flowchart illustrating a control method provided in at least one embodiment of the present disclosure. The outdoor unit includes a compressor 100, a reversing valve 200, and a water-cooled heat exchanger 301. Figure 12 As shown, the method for controlling the outdoor unit includes the following steps S101 to S103 to achieve the cooling function.

[0135] Step S101: Upon receiving the cooling mode start command, enter the cooling mode.

[0136] Step S102: The high-temperature and high-pressure gaseous refrigerant discharged from the compressor 100 enters the water-cooled heat exchanger 301 through the reversing valve 200, and then enters the indoor unit of the water source multi-split system.

[0137] Step S103: When the discharge pressure (also known as high pressure) of the compressor 100 is lower than the first threshold Pd_A2, the amount of refrigerant flowing through the first branch where the water-cooled heat exchanger 301 is located is reduced (303 is closed), and the second branch connected in parallel with the first branch where the water-cooled heat exchanger 301 is located is opened, so that the refrigerant flows through the second branch.

[0138] In step S103, the first threshold Pd_A2 ranges from 0.7 to 1.5 MPaG. In practical applications, the specific value of the first threshold Pd_A2 can be flexibly adjusted based on factors such as the outdoor unit's design parameters, operating environment, and heating efficiency. Figure 1 The reduction of refrigerant flow through the first branch containing the water-cooled heat exchanger 301 can be achieved by controlling the opening of the first throttling element, but is not limited to this. The opening degree of the first throttling element can be adjusted in real time according to the discharge pressure of the compressor 100 to precisely control the amount of refrigerant flowing through the first branch. Furthermore, when the discharge pressure of the compressor 100 is lower than the first threshold Pd_A2, in addition to opening the first throttling element, the states of other related valves can be adjusted simultaneously, such as closing or reducing the opening degree of the second throttling element, to ensure that the refrigerant can flow smoothly through the second branch, thereby achieving efficient operation of the refrigeration system. This control method not only improves refrigeration efficiency but also effectively reduces energy consumption and enhances the overall system performance.

[0139] In some embodiments, the outdoor unit includes a refrigerant radiator, and the refrigerant flowing through the first branch and / or the second branch flows through the third branch where the refrigerant radiator is located and the fourth branch connected in parallel with the third branch. To ensure that the refrigerant radiator 400 operates normally under cooling conditions, the method further includes: when the water temperature of the water-cooled heat exchanger 301 is lower than the limit that can be adjusted by the first branch and / or the second branch, the high-temperature and high-pressure gaseous refrigerant discharged by the compressor 100 flows into the third branch through the fifth branch, thereby increasing the operating temperature of the refrigerant radiator 400.

[0140] Among them, such as Figure 5 As shown, the operating temperature of the refrigerant radiator can be increased by using the solenoid valve 501 and the first one-way valve 502 installed on the fifth branch. The solenoid valve 501 allows refrigerant to flow into the third branch as needed, while the first one-way valve 502 ensures unidirectional flow of refrigerant in the third branch, preventing efficiency loss due to refrigerant backflow. When the water temperature is low and the operating temperature of the refrigerant radiator needs to be increased, the solenoid valve 501 opens, allowing the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 100 to flow into the third branch through the fifth branch for heat exchange with the refrigerant radiator. During this process, the first one-way valve 502 ensures the smooth flow of refrigerant from the fifth branch to the third branch while preventing refrigerant from flowing back from the third branch to the fifth branch, thus maintaining the stable operation of the refrigeration system. Through this design, the refrigeration system can automatically adjust the flow path and state of the refrigerant according to changes in ambient temperature, achieving efficient and energy-saving operation.

[0141] In some embodiments, to further improve the response to extreme operating conditions, the outdoor unit also includes a first shut-off valve 801. The high-temperature and high-pressure gaseous refrigerant discharged by the compressor 100 enters the water-cooled heat exchanger through the reversing valve 200 and then enters the indoor unit through the first shut-off valve 801. The method further includes: after the amount of refrigerant flowing through the first branch where the water-cooled heat exchanger is located decreases, obtaining the liquid subcooling degree at the location of the first shut-off valve 801, and identifying that when the liquid subcooling degree is greater than the preset subcooling degree threshold Tsc_A, increasing the amount of refrigerant flowing through the second branch.

[0142] The subcooling threshold Tsc_A ranges from 5 to 15 K. When the liquid subcooling exceeds the subcooling threshold Tsc_A, it indicates that the refrigerant in the water-cooled heat exchanger 301 has been overcooled. At this point, by increasing the amount of refrigerant flowing through the second branch, the refrigerant distribution in the refrigeration system can be effectively balanced, avoiding energy waste caused by overcooling. This adjustment process is automatically completed by the controller without manual intervention, thus ensuring the stable operation of the refrigeration system under extreme conditions.

[0143] In some embodiments, the method further includes: when the discharge pressure of the compressor 100 is not lower than the first threshold Pd_A2, obtaining the suction pressure of the compressor 100, and identifying when the suction pressure is less than a preset suction pressure threshold Ps_B, increasing the refrigerant flow rate of the sixth branch.

[0144] The suction pressure threshold Ps_B ranges from 0.5 to 0.8 MPaG. This adjustment strategy aims to address potential insufficient suction in compressor 100 under high-pressure operation. When the discharge pressure is not lower than the first threshold Pd_A2, it indicates that compressor 100 is under high workload. If the suction pressure is too low at this time, i.e., less than the suction pressure threshold Ps_B, it may lead to low compressor efficiency or even malfunction. Therefore, by increasing the refrigerant flow in the sixth branch, the suction capacity of compressor 100 can be effectively improved, ensuring stable operation of the refrigeration system under high load conditions.

[0145] In some embodiments, in order to prevent the indoor unit from shutting down under extreme operating conditions with low indoor unit operating load, the method further includes: when the indoor unit operating load is less than a threshold, allowing a portion of the refrigerant flowing through the fourth branch to bypass into the sixth branch.

[0146] In cases where the number of indoor units is small or the indoor temperature control shutdown is infrequent, the indoor unit operating load is relatively low. To prevent excessive refrigerant flow through the indoor unit from causing it to freeze and shut down, the fifth throttling element 601 is activated to bypass a portion of the refrigerant into the compressor 100, thereby reducing the refrigerant flow through the indoor unit and preventing it from freezing and shutting down.

[0147] Figure 14 This is a schematic diagram of a refrigerant heat dissipation control process in a refrigeration process provided in at least one embodiment of the present disclosure, as described in steps S101 to S103. Figure 15 This is a schematic diagram illustrating an example of a low-water-temperature heating control process in a cooling process provided by at least one embodiment of this disclosure. The specific details have already been described in detail above and will not be repeated here.

[0148] Figure 13 A flowchart illustrating another control method provided for at least one embodiment of this disclosure. (See attached diagram.) Figure 13 As shown, in Figure 12 Based on this, the method for controlling the outdoor unit also includes the following steps S201 to S203 to achieve the heating function.

[0149] Step S201: Upon receiving the heating mode start command, enter the heating mode.

[0150] Step S202: The high-temperature and high-pressure gaseous refrigerant discharged by the compressor 100 enters the indoor unit of the water source multi-split system through the reversing valve 200 and then enters the water-cooled heat exchanger 301.

[0151] Step S203: When the suction pressure (also known as low pressure) of the compressor 100 is higher than the second threshold Ps_A, the amount of refrigerant flowing through the first branch where the water-cooled heat exchanger is located is reduced, and the second branch connected in parallel with the first branch where the water-cooled heat exchanger is located is opened, so that the refrigerant flows through the second branch.

[0152] In step S203, the second threshold Ps_A ranges from 1.0 to 1.6 MPaG. In practical applications, the specific value of the second threshold Ps_A can be flexibly adjusted based on factors such as the outdoor unit's design parameters, operating environment, and heating efficiency. For example, in cold regions, the value of the second threshold Ps_A can be appropriately increased to improve heating efficiency; while in warm regions, the value of the second threshold Ps_A can be appropriately decreased to reduce energy consumption. By reasonably setting the second threshold Ps_A, it can be ensured that the outdoor unit maintains good heating performance under different environments. Figure 1The reduction of refrigerant flow through the first branch containing the water-cooled heat exchanger 301 can be achieved by controlling the opening of the first throttling element, but is not limited to this. The opening degree of the first throttling element can be adjusted in real time according to the suction pressure of the compressor 100 to precisely control the amount of refrigerant flowing through the first branch. Furthermore, when the suction pressure of the compressor 100 is higher than the second threshold Ps_A, in addition to opening the first throttling element, the states of other related valves can be adjusted simultaneously, such as closing or reducing the opening degree of the second throttling element, to ensure that the refrigerant can flow smoothly through the second branch, thereby achieving efficient operation of the refrigeration system. This control method not only improves refrigeration efficiency but also effectively reduces energy consumption and enhances the overall system performance.

[0153] In some embodiments, the outdoor unit includes a refrigerant radiator, and the refrigerant flowing through the third branch where the refrigerant radiator is located and / or the fourth branch connected in parallel with the third branch flows through the first branch and the second branch. To ensure the refrigerant radiator 400 operates normally under heating conditions, the method further includes: when the water temperature of the water-cooled heat exchanger is lower than the adjustable limit of the first branch and / or the second branch, the high-temperature, high-pressure gaseous refrigerant discharged from the compressor 100 flows into the third branch through the fifth branch, thereby increasing the operating temperature of the refrigerant radiator.

[0154] Among them, such as Figure 5 As shown, the operating temperature of the refrigerant radiator can be increased by using the solenoid valve 501 and the first check valve 502 installed on the fifth branch. The solenoid valve 501 allows refrigerant to flow into the third branch as needed, while the first check valve 502 ensures unidirectional flow of refrigerant in the third branch, avoiding efficiency loss caused by refrigerant backflow. The fifth branch, acting as an auxiliary heater, can be activated when the water temperature is extremely low or the ambient temperature is harsh, providing additional heat to the refrigerant flowing through the third branch. This ensures that the refrigerant radiator 400 can output refrigerant at a sufficient temperature to meet heating requirements, achieving the desired balance between energy consumption and heating effect.

[0155] In some embodiments, the method further includes: gradually reducing the refrigerant flow rate of the first branch and simultaneously increasing the refrigerant flow rate of the second branch as the water temperature of the water-cooled heat exchanger gradually increases. This dynamic adjustment mechanism ensures that the system can operate efficiently and stably under different water temperature conditions. As the water temperature gradually increases, the high-temperature cooling demand of the first branch gradually decreases, so reducing the refrigerant flow rate of the first branch avoids unnecessary energy consumption. At the same time, the medium- or low-temperature cooling demand of the second branch may increase, so simultaneously increasing the refrigerant flow rate of the second branch ensures that the system can respond promptly and provide sufficient cooling capacity. This dynamic refrigerant flow rate allocation strategy not only improves the system's energy efficiency but also enhances its adaptability to different operating conditions, providing users with a more comfortable and energy-efficient user experience.

[0156] In some embodiments, the outdoor unit further includes a third throttling element 401 disposed on the third branch, and the method further includes: acquiring the refrigerant heat dissipation temperature of the refrigerant radiator; when the refrigerant heat dissipation temperature is less than a first temperature threshold T_finA, acquiring the opening degree of the third throttling element 401, identifying that the opening degree of the third throttling element 401 has not reached the minimum value, reducing the opening degree of the third throttling element 401, identifying that the opening degree of the third throttling element 401 has reached the minimum value, allowing the high-temperature and high-pressure gaseous refrigerant discharged by the compressor 100 to flow into the refrigerant radiator through the fifth branch; and when the refrigerant heat dissipation temperature is not less than the first temperature threshold T_finA, identifying that the refrigerant heat dissipation temperature is greater than a second temperature threshold T_finB, increasing the refrigerant flow rate of the third branch while decreasing the refrigerant flow rate of the fourth branch, and identifying that the refrigerant heat dissipation temperature is not greater than the second temperature threshold T_finB, keeping the refrigerant flow rates of the third branch and the fourth branch unchanged.

[0157] The second temperature threshold T_finB is greater than the first temperature threshold T_finA. The first temperature threshold T_finA ranges from 10 to 55°C, and the second temperature threshold T_finB ranges from 20 to 75°C. Furthermore, the specific values ​​of the first temperature threshold T_finA and the second temperature threshold T_finB can be adjusted according to actual usage conditions to achieve optimal cooling performance and energy efficiency ratio. In practical implementation, the values ​​of the first temperature threshold T_finA and the second temperature threshold T_finB can be flexibly selected based on factors such as the outdoor unit's operating environment, the heat dissipation performance of the refrigerant radiator, and the compressor's operating status to achieve more precise refrigerant flow control and a higher energy efficiency ratio.

[0158] In some embodiments, the outdoor unit further includes a second shut-off valve, through which the high-temperature, high-pressure gaseous refrigerant discharged from the indoor unit compressor 100 sequentially passes through the reversing valve 200 and the second shut-off valve into the indoor unit. To further improve the response to extreme operating conditions, the method further includes: after reducing the amount of refrigerant flowing through the first branch containing the water-cooled heat exchanger, obtaining the compressor's exhaust temperature; if the exhaust temperature exceeds a preset superheat threshold Td_A, increasing the amount of refrigerant flowing through the second branch; and if the exhaust temperature does not exceed the preset superheat threshold Td_A, decreasing the amount of refrigerant flowing through the third branch.

[0159] For example, according to Figure 8The refrigerant flow rate can be increased by widening the opening of the first throttling element 302 on the second branch, and decreased by narrowing the opening of the third throttling element 401 on the third branch, thus achieving a more precise refrigerant flow distribution and optimizing the overall system's operating efficiency and energy efficiency ratio. Furthermore, by monitoring the exhaust temperature (superheat) in real time and dynamically adjusting the refrigerant flow distribution based on temperature changes, system performance degradation or malfunctions caused by excessively high or low exhaust temperatures are effectively avoided, improving system stability and reliability. In practical operation, widening the opening of the first throttling element 302 on the second branch and narrowing the opening of the third throttling element 401 on the third branch can be achieved automatically through preset control algorithms or programs, or manually adjusted as needed to meet operational requirements under different conditions.

[0160] In some embodiments, the method further includes: when the suction pressure of the compressor 100 is not higher than the second threshold Ps_A, acquiring the discharge pressure of the compressor 100; when the discharge pressure is greater than the preset discharge pressure threshold Pd_A, simultaneously increasing the refrigerant flow rates of the third branch and the fourth branch; and when the discharge pressure is not greater than the preset discharge pressure threshold Pd_A, keeping the refrigerant flow rates of the third branch and the fourth branch unchanged.

[0161] For R410A refrigerant, the discharge pressure threshold Pd_A ranges from 3.0 to 3.6 MPaG. When the suction pressure of compressor 100 is not higher than the second threshold Ps_A and the discharge pressure is within the preset range, maintaining the refrigerant flow rates of the third and fourth branches unchanged helps to maintain stable system operation and avoid unnecessary energy consumption. This adjustment strategy comprehensively considers the impact of suction and discharge pressures on system performance, and achieves comprehensive optimization of system operation through fine-tuning of refrigerant flow rates. Furthermore, setting a reasonable discharge pressure threshold Pd_A range for specific refrigerants such as R410A ensures the effectiveness and applicability of the adjustment strategy.

[0162] Figure 16 A schematic diagram illustrating an example of a refrigerant heat dissipation control process during heating, provided for at least one embodiment of this disclosure. Figure 17 This is a flowchart illustrating an example of high-temperature heating control in a heating process provided by at least one embodiment of this disclosure. The specific details have already been described in detail above and will not be repeated here.

[0163] Figure 18 This is a structural block diagram of a water source multi-split system provided in at least one embodiment of this disclosure. (See diagram below.) Figure 18As shown, the water source multi-split system 1 includes an indoor unit 20 and an outdoor unit 10 as provided in any embodiment of the present disclosure, wherein the indoor unit 20 includes a plurality of indoor units connected to the outdoor unit 10 for the water source multi-split system.

[0164] Although embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. An outdoor unit for a multi-split air conditioning system, characterized in that, include: The compressor has an intake port and an exhaust port; First shut-off valve; A reversing valve having a first interface and a second interface, wherein the first interface is connected to the exhaust port; as well as, A first heat exchanger has a first port and a second port, the first port being connected to the second interface of the reversing valve and the second port being connected to the first shut-off valve. The second branch, which is connected in parallel with the first branch where the first heat exchanger is located, is provided with a first throttling element. One end of the second branch is provided in the connecting pipe between the reversing valve and the first heat exchanger, and the other end of the second branch is provided in the connecting pipe between the second port of the first heat exchanger and the first shut-off valve. In cooling mode, the first throttling element is in the open state when the compressor's discharge pressure is less than a first threshold; in heating mode, the first throttling element is in the open state when the compressor's suction pressure is greater than a second threshold.

2. The outdoor unit for a multi-split air conditioning system according to claim 1, characterized in that, Also includes: A refrigerant radiator is provided in the third branch, which is connected in parallel to the connecting pipe between the second port of the first heat exchanger and the first shut-off valve. The refrigerant radiator is used to dissipate heat from the circuit board of the water source multi-split unit.

3. The outdoor unit for a multi-split air conditioning system according to claim 1 or 2, characterized in that, The first branch is provided with a second throttling element; and the second throttling element is connected in series with the first heat exchanger.

4. The outdoor unit for a multi-split air conditioning system according to claim 3, characterized in that, The third branch where the refrigerant radiator is located is equipped with a third throttling element connected in series with the refrigerant radiator; The connecting pipeline between the second port of the first heat exchanger and the first shut-off valve is provided with a fourth throttling element as a fourth branch, and the fourth throttling element is connected to the second throttling element.

5. The outdoor unit for a multi-split air conditioning system according to claim 3, characterized in that, Also includes: A first bypass branch is provided between the compressor and the refrigerant radiator. The first bypass branch is provided with a solenoid valve and a first check valve connected in series with the solenoid valve. The solenoid valve is connected to the exhaust port of the compressor, and the first check valve is connected to the refrigerant radiator.

6. The outdoor unit for a multi-split air conditioning system according to claim 1, characterized in that, Also includes: A second heat exchanger is connected to the second port of the first heat exchanger; and The second bypass branch has one end connected to the connecting pipe between the second heat exchanger and the second port of the first heat exchanger. After passing through the fifth throttling element and the second heat exchanger, the other end of the second bypass branch is connected to the suction port of the compressor.

7. A method for controlling an outdoor unit of a water source multi-split air conditioning system, said outdoor unit comprising a compressor, a reversing valve, and a first heat exchanger, characterized in that, The method includes: Upon receiving a command to activate cooling mode, the device enters cooling mode. The high-temperature, high-pressure gaseous refrigerant discharged from the compressor enters the first heat exchanger through the reversing valve, and then enters the indoor unit of the water source multi-split system. When the compressor's discharge pressure is lower than the first threshold, the amount of refrigerant flowing through the first branch where the first heat exchanger is located is reduced, and the second branch connected in parallel with the first branch where the first heat exchanger is located is opened, so that the refrigerant flows through the second branch.

8. The method according to claim 7, characterized in that, Also includes: Upon receiving a command to activate heating mode, the device enters heating mode. The high-temperature, high-pressure gaseous refrigerant discharged from the compressor enters the indoor unit of the water source multi-split system through the reversing valve and then enters the first heat exchanger. When the compressor's suction pressure is higher than the second threshold, the amount of refrigerant flowing through the first branch where the first heat exchanger is located is reduced, and the second branch connected in parallel with the first branch where the first heat exchanger is located is opened, so that the refrigerant flows through the second branch.

9. The method according to claim 7, characterized in that, The outdoor unit includes a refrigerant radiator. The refrigerant flowing through the first branch and / or the second branch flows through the third branch where the refrigerant radiator is located and the fourth branch connected in parallel with the third branch. When the water temperature of the first heat exchanger is lower than the adjustable limit of the first branch and / or the second branch, the high-temperature and high-pressure gaseous refrigerant discharged by the compressor flows into the third branch through the fifth branch, thereby increasing the operating temperature of the refrigerant radiator.

10. A multi-split water source unit, characterized in that, It includes an indoor unit and an outdoor unit for a water-source multi-split system as described in any one of claims 1-6, wherein, The indoor unit includes multiple indoor units connected to the outdoor unit of the water source multi-split system.

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