Outdoor unit and air conditioning apparatus

Abstract

The application discloses an outdoor unit and air conditioning equipment, wherein a relay is designed, a first port of the relay is connected with a liquid pipe of an indoor heat exchanger, a second port is connected with a liquid pipe of an outdoor heat exchanger, the second port is connected with a third port through a connecting pipeline, a fourth port is connected with a suction port of a compressor, and an adjusting valve is arranged on the connecting pipeline; in a heating mode, when the water inlet temperature of the outdoor heat exchanger reaches a first set water temperature threshold, the adjusting valve is opened, and the opening degree of the adjusting valve is adjusted according to the outdoor environment temperature and the compressor discharge pressure, so that the working output of the compressor is reduced, the load is stabilized, the normal operation of the compressor is ensured, the outdoor unit can still be normally and stably operated when the water inlet temperature reaches the first set water temperature threshold, and the technical problem that the existing technology cannot be normally operated in high water temperature heating is solved.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and more particularly to outdoor units and air conditioning equipment. Background Technology

[0002] Water source multi-split air conditioning system (referred to as water source unit) usually uses an outdoor side plate heat exchanger as the water source side heat exchanger. One of the flow channels of the outdoor side plate heat exchanger is the refrigerant flow channel, and the other flow channel is the water flow channel. Heat exchange between refrigerant and water is realized in the outdoor plate heat exchanger, thereby realizing the air conditioning cooling and heating functions.

[0003] Existing water source heaters cannot operate stably when heating at high water temperatures (inlet water temperature above 30℃), resulting in problems such as excessively high low-pressure conditions. For example... Figure 1 As shown, the red curve is the low-pressure curve, and the other curves are the high-pressure curves at the compressor discharge port, gas-side shut-off valve, liquid-side shut-off valve, etc.

[0004] When the unit's water source is connected to the municipal heating network, the inlet water temperature will reach over 40°C, at which point the unit will be unable to start normally. Summary of the Invention

[0005] This invention proposes an outdoor unit that solves the technical problem of the inability to operate normally when heating at high water temperatures in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides an outdoor unit, comprising: compressor; Outdoor heat exchanger; A repeater has a first port, a second port, a third port, and a fourth port, as well as a first refrigerant passage connecting the first port and the second port, and a second refrigerant passage connecting the third port and the fourth port; the first port is connected to the liquid pipe of the indoor heat exchanger, and the second port is connected to the liquid pipe of the outdoor heat exchanger; the second port is connected to the third port through a connecting pipe, and the fourth port is connected to the suction port of the compressor; a regulating valve is provided on the connecting pipe; The control module is configured to: in heating mode, when the inlet water temperature of the outdoor heat exchanger reaches the first set water temperature threshold, open the regulating valve and adjust the opening degree of the regulating valve according to the outdoor ambient temperature and the compressor exhaust pressure.

[0007] In some embodiments of this application, adjusting the opening of the regulating valve according to the outdoor ambient temperature and the compressor discharge pressure specifically includes: The water temperature compensation opening is obtained by multiplying the difference between the first compensation constant and the outdoor ambient temperature, the first temperature correction coefficient, and the current opening of the regulating valve. The pressure compensation opening is obtained by multiplying the difference between the second compensation constant and the compressor discharge pressure and the first pressure correction coefficient. The target opening of the control valve is obtained by summing the water temperature compensation opening, pressure compensation opening, and the current opening of the control valve.

[0008] In some embodiments of this application, the outdoor unit further includes: A bypass pipeline, one end of which is connected to the exhaust port of the compressor and the other end of which is connected to the intake port of the compressor, is provided with a bypass valve. The control module is also configured to: In heating mode, when the inlet water temperature of the outdoor heat exchanger reaches the second set water temperature threshold and only one indoor unit is turned on, the bypass valve is adjusted according to the outdoor ambient temperature and the compressor discharge pressure. The second set water temperature threshold is greater than the first set water temperature threshold.

[0009] In some embodiments of this application, adjusting the on / off state of the bypass valve according to the outdoor ambient temperature and the compressor discharge pressure specifically includes: Calculate the pressure condition judgment coefficient based on the second pressure correction coefficient, compressor discharge pressure, and system pressure opening threshold. Based on the second temperature correction coefficient, outdoor ambient temperature, and ambient temperature opening threshold, calculate the temperature condition judgment coefficient. The sum of the pressure condition judgment coefficient and the temperature condition judgment coefficient is calculated to obtain the total opening judgment coefficient; Determine whether the total coefficient of the activation judgment has reached the coefficient threshold; If yes, the bypass valve will be opened; otherwise, the bypass valve will be closed.

[0010] In some embodiments of this application, the calculation of the pressure condition judgment coefficient based on the second pressure correction coefficient, the compressor discharge pressure, and the system pressure opening threshold specifically includes: C_p = K_p × (P_sys / P_set); Where C_p is the pressure condition judgment coefficient; K_p is the second pressure correction factor; P_sys is the compressor discharge pressure; P_set is the system pressure threshold.

[0011] In some embodiments of this application, the calculation of the temperature condition judgment coefficient based on the second temperature correction coefficient, the outdoor ambient temperature, and the ambient temperature activation threshold specifically includes: C_t=K_t×[(T_env-T_set) / (m3-T_set)+m4]; Where C_t is the temperature condition judgment coefficient; K_t is the second temperature correction coefficient; T_env is the outdoor ambient temperature; T_set is the threshold for enabling ambient temperature; m3 is the third compensation constant; m4 is the fourth compensation constant.

[0012] In some embodiments of this application, the control module is further configured as follows: Determine if the following condition is met: In heating mode, the inlet water temperature of the outdoor heat exchanger reaches the first set water temperature threshold. If satisfied, then execute: When the compressor discharge pressure is higher than the first high-pressure protection threshold A1 but not higher than the second high-pressure protection threshold B1, the first frequency control strategy is executed on the compressor. When the compressor discharge pressure is higher than the second high-pressure protection threshold B1 but not higher than the third high-pressure protection threshold C1, the second frequency control strategy is executed on the compressor. When the compressor discharge pressure is higher than the third high-pressure protection threshold C1, the third frequency control strategy is implemented for the compressor. If not satisfied, then execute: When the compressor discharge pressure is higher than the fourth high-pressure protection threshold A2 but not higher than the fifth high-pressure protection threshold B2, the first frequency control strategy is executed on the compressor. When the compressor discharge pressure is higher than the fifth high-pressure protection threshold B2 but not higher than the sixth high-pressure protection threshold C2, the second frequency control strategy is implemented for the compressor. When the compressor discharge pressure is higher than the sixth high-pressure protection threshold C2, the third frequency control strategy is implemented for the compressor. Where A2 < A1 < B2 < B1 < C2 < C1.

[0013] In some embodiments of this application, the control module is further configured as follows: Determine if the following condition is met: In heating mode, the inlet water temperature of the outdoor heat exchanger reaches the first set water temperature threshold. If the conditions are met, then when the compressor suction pressure is higher than the first low-pressure protection threshold D1, the fourth frequency control strategy is executed on the compressor. If the conditions are not met, then when the compressor suction pressure is higher than the second low-pressure protection threshold D2, the fourth frequency control strategy is executed on the compressor; where D1 > D2.

[0014] In some embodiments of this application, the first frequency control strategy, the second frequency control strategy, and the third frequency control strategy have a higher priority than the fourth frequency control strategy.

[0015] Air conditioning equipment, including the outdoor unit mentioned above.

[0016] The technical solution of the present invention has the following technical effects compared with the prior art: The outdoor unit and air conditioning equipment of the present invention, through the design of a repeater, has a first port connected to the liquid pipe of the indoor heat exchanger, a second port connected to the liquid pipe of the outdoor heat exchanger, a third port connected to the second port through a connecting pipe, and a fourth port connected to the suction port of the compressor. A regulating valve is provided on the connecting pipe. In the heating mode, when the inlet water temperature of the outdoor heat exchanger reaches the first set water temperature threshold, the regulating valve is opened, and the opening degree of the regulating valve is adjusted according to the outdoor ambient temperature and the compressor discharge pressure to reduce the compressor's work output, stabilize the load, and ensure the normal operation of the compressor. This achieves normal and stable operation of the outdoor unit when the inlet water temperature is greater than or equal to the first set water temperature threshold, solving the technical problem in the prior art that the unit cannot operate normally when heating at high water temperatures.

[0017] Other features and advantages of the present invention will become clearer after reading the detailed embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a graph showing the high and low pressure curves when the machine is shut down. Figure 2 A schematic diagram of the structure of an embodiment of the outdoor unit of the present invention; Figure 3 This is a schematic diagram showing the refrigerant flow direction when the regulating valve is open; Figure 4 A schematic diagram showing the refrigerant flow direction when the bypass valve is open; Figure 5 A flowchart of one embodiment of the steps performed by the control module; Figure 6 A flowchart of yet another embodiment of the steps performed by the control module; Figure 7 A flowchart of yet another embodiment of the steps performed by the control module; Figure 8 This is a graph showing the high and low pressure curves when the machine is shut down. Figure 9 For stable operation, high pressure and low pressure curves are shown; Figure 10A flowchart of yet another embodiment of the steps performed by the control module; Figure 11 A flowchart of yet another embodiment of the steps performed by the control module; Figure 12 A flowchart of yet another embodiment of the steps performed by the control module.

[0020] Figure label: 11. Compressor; 12. Four-way valve; 13. Gas-side shut-off valve; 14. Liquid-side shut-off valve; 15. Repeater; 16. Outdoor heat exchanger; 17. Connecting pipelines; 18. Regulating valves; 19. Bypass pipeline; 20. Bypass valve. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0023] 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 technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0024] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0025] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0026] The following disclosure provides many different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0027] Air conditioners execute refrigeration and heating cycles using a compressor, condenser, expansion valve, and evaporator. These cycles are controlled by a controller, which manages the refrigerant flow and the opening of the expansion valve. The refrigeration and heating cycles involve a series of processes including compression, condensation, expansion, and evaporation, ultimately supplying refrigerant to the conditioned and heat-exchanged air.

[0028] The compressor compresses refrigerant gas under high temperature and pressure and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and the heat is released to the surrounding environment through the condensation process.

[0029] The expansion valve expands the high-temperature, high-pressure liquid refrigerant condensed in the condenser into a low-pressure liquid refrigerant. The evaporator evaporates the expanded refrigerant in the expansion valve, returning the low-temperature, low-pressure refrigerant gas to the compressor. The evaporator achieves its cooling effect by utilizing the latent heat of refrigerant evaporation to exchange heat with the material being cooled. Throughout the cycle, the air conditioner regulates the temperature of the indoor space.

[0030] An air conditioner outdoor unit refers to the part of the refrigeration cycle that includes the compressor and the outdoor heat exchanger. An air conditioner indoor unit includes the indoor heat exchanger, and an expansion valve can be provided in either the outdoor or indoor unit.

[0031] The indoor and outdoor heat exchangers function as either condensers or evaporators. When the indoor heat exchanger is used as a condenser, the air conditioner functions as a heater in heating mode; when the indoor heat exchanger is used as an evaporator, the air conditioner functions as a cooler in cooling mode.

[0032] The air conditioning equipment in this embodiment includes an outdoor unit and several indoor units. The outdoor unit is connected to each of the indoor units.

[0033] The indoor unit is equipped with an indoor heat exchanger. The gas pipe of the indoor heat exchanger is connected to the gas-side shut-off valve 13 of the outdoor unit, and the liquid pipe of the indoor heat exchanger is connected to the liquid-side shut-off valve 14 of the outdoor unit. A throttling device is installed on the liquid pipe of the indoor heat exchanger.

[0034] The outdoor unit of this embodiment includes a compressor 11, a four-way valve 12, an outdoor heat exchanger 16, a repeater 15, a control module, etc., see below. Figure 2 As shown.

[0035] The compressor 11 has an exhaust port and an intake port.

[0036] The outdoor heat exchanger 16 has a refrigerant channel and a water channel; the refrigerant in the refrigerant channel exchanges heat with the water in the water channel. One end of the refrigerant channel is connected to the liquid pipe of the outdoor heat exchanger, and the other end is connected to the gas pipe of the outdoor heat exchanger. One end of the water channel is connected to the inlet pipe, and the other end is connected to the outlet pipe.

[0037] The repeater 15 has a first port a, a second port b, a third port c, and a fourth port d, as well as a first refrigerant passage connecting the first port a and the second port b, and a second refrigerant passage connecting the third port c and the fourth port d. The first port a is connected to the liquid pipe of the indoor heat exchanger, and the second port b is connected to the liquid pipe of the outdoor heat exchanger. The second port b is connected to the third port c through a connecting pipe 17, and the fourth port d is connected to the suction port of the compressor. A regulating valve 18 is provided on the connecting pipe 17. The first port a is connected to the liquid pipe of the indoor heat exchanger through a liquid-side shut-off valve 14.

[0038] The control module is configured such that, in heating mode, when the inlet water temperature of the outdoor heat exchanger reaches the first set water temperature threshold, the regulating valve is opened, and the opening degree of the regulating valve 18 is adjusted according to the outdoor ambient temperature and the compressor exhaust pressure.

[0039] Therefore, in heating mode, the control module specifically performs the following steps, see below. Figure 5 As shown.

[0040] Step S11: Obtain the inlet water temperature of the outdoor heat exchanger.

[0041] Step S12: Determine whether the inlet water temperature of the outdoor heat exchanger has reached the first set water temperature threshold.

[0042] If so, that is, the inlet water temperature of the outdoor heat exchanger is greater than or equal to the first set water temperature threshold, then proceed to step S13.

[0043] Step S13: Open the regulating valve and adjust the opening degree of the regulating valve according to the outdoor ambient temperature and the compressor discharge pressure.

[0044] The regulating valve 18 in this application is an electronic expansion valve. The outdoor heat exchanger in this application is a plate heat exchanger.

[0045] In heating mode, the high-temperature and high-pressure refrigerant gas discharged from the compressor 11 flows through the four-way valve 12 to the gas-side shut-off valve 13, then through the gas-side shut-off valve 13 to the gas pipe of the indoor heat exchanger, enters the indoor heat exchanger for heat exchange, becomes a medium-temperature and high-pressure liquid, flows out from the liquid pipe of the indoor heat exchanger, flows through the liquid-side shut-off valve 14 to the first port a of the relay 15, then enters the first refrigerant channel of the relay 15, and then flows out from the second port b. If the regulating valve 18 is closed, the refrigerant flowing out from the second port b enters the liquid pipe of the outdoor heat exchanger 16, then enters the refrigerant flow channel of the outdoor heat exchanger 16, and after heat exchange, flows from the gas pipe of the outdoor heat exchanger 16 to the four-way valve 12, and then flows back to the compressor's suction port through the four-way valve 12.

[0046] If regulating valve 18 is open, the refrigerant flowing out from the second port b splits into two paths. One path enters the outdoor heat exchanger 16, while the other path flows through connecting pipe 17 to the third port c of repeater 15, then into the second refrigerant passage of repeater 15, and finally flows out from the fourth port d, returning to the compressor's suction port. (See [reference]) Figure 3 As shown.

[0047] The refrigerant flowing from the indoor unit to the relay 15, due to the opening of the regulating valve 18, allows some of the high-temperature refrigerant to flow directly into the suction port of the compressor 11 without passing through the outdoor heat exchanger 16. This reduces the compressor's power output, stabilizes the pressure ratio and load, ensures stable operation of the outdoor unit, and enables normal heating operation under high inlet water temperature (inlet water temperature greater than or equal to the first set water temperature threshold).

[0048] The outdoor ambient temperature affects the inlet water temperature of the outdoor heat exchanger 16, and the compressor discharge pressure affects whether the outdoor unit can operate stably. Therefore, the opening of the regulating valve 18 is adjusted according to the outdoor ambient temperature and the compressor discharge pressure so that some high-temperature refrigerant can flow directly into the compressor's suction port without passing through the outdoor heat exchanger, thereby reducing the compressor's power output and ensuring the normal and stable operation of the outdoor unit.

[0049] Therefore, in this embodiment, the outdoor unit is designed with a repeater 15. The first port a of the repeater 15 is connected to the liquid pipe of the indoor heat exchanger, the second port b is connected to the liquid pipe of the outdoor heat exchanger, the second port b is connected to the third port c through the connecting pipe 17, and the fourth port d is connected to the suction port of the compressor. A regulating valve 18 is provided on the connecting pipe 17. In heating mode, when the inlet water temperature of the outdoor heat exchanger reaches the first set water temperature threshold, the regulating valve is opened, and the opening degree of the regulating valve 18 is adjusted according to the outdoor ambient temperature and the compressor discharge pressure to reduce the compressor's work output, stabilize the load, and ensure the normal operation of the compressor. This achieves normal and stable operation of the outdoor unit when the inlet water temperature is greater than or equal to the first set water temperature threshold, solving the technical problem in the prior art that the unit cannot operate normally when heating at high water temperatures.

[0050] In some embodiments of this application, the opening of the regulating valve is adjusted according to the outdoor ambient temperature and the compressor discharge pressure, specifically including the following steps, see below. Figure 6 As shown.

[0051] Step S13-1: Integrate the difference between the first compensation constant m1 and the outdoor ambient temperature, the first temperature correction coefficient K1, and the current opening degree S_base of the regulating valve to obtain the water temperature compensation opening degree ΔS_temp.

[0052] Step S13-2: Integrate the difference between the second compensation constant m2 and the compressor discharge pressure and the first pressure correction coefficient K2 to obtain the pressure compensation opening ΔS_press.

[0053] Step S13-3: Sum the water temperature compensation opening ΔS_temp, the pressure compensation opening ΔS_press, and the current opening S_base of the control valve to obtain the target opening S_final of the control valve. Adjust the opening of the control valve to the target opening S_final.

[0054] Therefore, the formula for calculating the water temperature compensation opening ΔS_temp is: ΔS_temp=K1×(m1-OAT)×S_base; K1: First temperature correction factor; m1: First compensation constant; m1 is a positive number, for example, m1=15; OAT: Outdoor ambient temperature (°C); S_base: Current opening degree of the regulating valve.

[0055] The formula for calculating the pressure compensation opening ΔS_press is: ΔS_press = K2 × (m2 - P_sys); K2: First pressure correction factor; m2: Second compensation constant; m2 is a positive number, for example, m2=2.0; P_sys: Compressor discharge pressure, i.e., the overall system pressure (MPa).

[0056] The formula for calculating the target opening degree S_final of the control valve: S_final=S_base+ΔS_temp+ΔS_press.

[0057] The target opening degree S_final of the control valve is calculated by combining the inlet water temperature compensation opening degree ΔS_temp, the pressure compensation opening degree ΔS_press, and the current opening degree S_base of the control valve.

[0058] By designing steps S13-1 to S13-3, the water temperature compensation opening ΔS_temp is calculated based on the first compensation constant m1, the outdoor ambient temperature OAT, the first temperature correction coefficient K1, and the current opening degree S_base of the regulating valve. The pressure compensation opening ΔS_press is calculated based on the second compensation constant m2, the compressor discharge pressure P_sys, and the first pressure correction coefficient K2. Then, the sum of the water temperature compensation opening ΔS_temp, the pressure compensation opening ΔS_press, and the current opening degree S_base of the regulating valve is calculated to obtain the target opening degree S_final of the regulating valve. Since factors such as the outdoor ambient temperature OAT, the compressor discharge pressure P_sys, and the current opening degree S_base of the regulating valve are comprehensively considered, the target opening degree S_final of the regulating valve can be accurately calculated. The opening degree of the regulating valve is adjusted to the target opening degree to ensure the normal and stable operation of the outdoor unit.

[0059] In some embodiments of this application, the outdoor unit also includes a bypass pipe 19.

[0060] The bypass line 19 is connected at one end to the exhaust port of the compressor 11 and at the other end to the intake port of the compressor 11. A bypass valve 20 is provided on the bypass line 19.

[0061] The control module is also configured as follows: In heating mode, when the inlet water temperature of the outdoor heat exchanger reaches the second set water temperature threshold and only one indoor unit is turned on, the bypass valve 20 is adjusted according to the outdoor ambient temperature and the compressor discharge pressure; wherein, the second set water temperature threshold is greater than the first set water temperature threshold.

[0062] For example, the second set water temperature threshold is 50°C, and the first set water temperature threshold is 45°C.

[0063] In heating mode, the control module performs the following steps, see below. Figure 7 As shown.

[0064] Step S21: Obtain the inlet water temperature of the outdoor heat exchanger.

[0065] Step S22: Determine whether the following conditions are met: the inlet water temperature of the outdoor heat exchanger reaches the second set water temperature threshold, and only one indoor unit is turned on.

[0066] If the conditions are met, i.e., the inlet water temperature of the outdoor heat exchanger is greater than or equal to the second set water temperature threshold, and only one indoor unit is turned on, then step S23 is executed.

[0067] Step S23: Adjust the bypass valve opening and closing according to the outdoor ambient temperature and compressor discharge pressure.

[0068] See Figure 4 As shown, when the bypass valve 20 is opened, some of the high-temperature refrigerant discharged from the exhaust port of the compressor 11 flows directly back to the suction port of the compressor 11 through the bypass pipe 19, reducing the effective output capacity of the outdoor unit, reducing the heat load of the outdoor heat exchanger, and stabilizing the suction and discharge pressure and temperature of the compressor.

[0069] The outdoor ambient temperature affects the inlet water temperature of the outdoor heat exchanger, and the compressor discharge pressure affects whether the outdoor unit can operate stably. Therefore, the bypass valve 20 is controlled according to the outdoor ambient temperature and the compressor discharge pressure to allow some high-temperature refrigerant to flow directly into the suction port of the compressor 11, thereby reducing the compressor's power output and ensuring the normal and stable operation of the outdoor unit.

[0070] In heating mode, when the inlet water temperature of the outdoor heat exchanger 16 is greater than or equal to the second set water level threshold, if only one indoor unit is operating, the capacity ratio (indoor unit capacity / outdoor unit capacity) is low, which can easily lead to shutdown. That is, even with extremely high inlet water temperatures and only one indoor unit operating, the unit may still shut down after running for a period of time. Figure 8 As shown, Figure 8 The red and green curves at the top represent high-pressure curves, while the pink curve at the bottom represents low-pressure curves. By adding control logic to the bypass valve, the unit can operate stably, such as... Figure 9 As shown, Figure 9 The upper curve is the high-pressure curve, and the lower curve is the low-pressure curve.

[0071] In some embodiments of this application, the bypass valve is adjusted based on the outdoor ambient temperature and the compressor discharge pressure, specifically including the following steps, see [link to relevant documentation]. Figure 10 As shown.

[0072] Step S23-1: Calculate the pressure condition judgment coefficient C_p based on the second pressure correction coefficient K_p, the compressor discharge pressure P_sys, and the system pressure opening threshold P_set.

[0073] Step S23-2: Calculate the temperature condition judgment coefficient C_t based on the second temperature correction coefficient K_t, the outdoor ambient temperature T_env, and the ambient temperature opening threshold T_set.

[0074] Step S23-3: Calculate the sum of the pressure condition judgment coefficient C_p and the temperature condition judgment coefficient C_t to obtain the total opening judgment coefficient C_open. C_open = C_p + C_t.

[0075] Step S23-4: Determine whether the total coefficient C_open has reached the coefficient threshold.

[0076] If so, that is, if the total coefficient C_open is greater than or equal to the coefficient threshold, then proceed to step S23-5: control the bypass valve to open.

[0077] If not, i.e., if the total coefficient C_open is less than the coefficient threshold, then proceed to step S23-6: control the bypass valve to close.

[0078] By designing steps S23-1 to S23-6, the pressure condition judgment coefficient C_p is calculated based on the second pressure correction coefficient K_p, the compressor discharge pressure P_sys, and the system pressure opening threshold P_set; the temperature condition judgment coefficient C_t is calculated based on the second temperature correction coefficient K_t, the outdoor ambient temperature T_env, and the ambient temperature opening threshold T_set; the sum of the pressure condition judgment coefficient C_p and the temperature condition judgment coefficient C_t is calculated to obtain the total opening judgment coefficient C_open; if the total opening judgment coefficient C_open ≥ the coefficient threshold, the bypass valve is controlled to open; if the total opening judgment coefficient C_open < the coefficient threshold, the bypass valve is controlled to close. Since factors such as the compressor discharge pressure P_sys and the outdoor ambient temperature T_env are comprehensively considered, a relatively accurate total opening judgment coefficient C_open can be calculated. Therefore, by accurately determining whether to open the bypass valve based on the relationship between the total opening judgment coefficient C_open and the coefficient threshold, the normal and stable operation of the outdoor unit is ensured.

[0079] In some embodiments of this application, a pressure condition judgment coefficient is calculated based on a second pressure correction coefficient, compressor discharge pressure, and system pressure opening threshold, specifically including: C_p = K_p × (P_sys / P_set); in, C_p is the pressure condition judgment coefficient; K_p is the second pressure correction factor; P_sys is the compressor discharge pressure; P_set is the system pressure threshold.

[0080] Using the above calculation formula, the pressure condition judgment coefficient C_p can be accurately calculated, and then the accurate opening judgment total coefficient C_open can be calculated.

[0081] In some embodiments of this application, a temperature condition judgment coefficient is calculated based on a second temperature correction coefficient, outdoor ambient temperature, and ambient temperature activation threshold, specifically including: C_t=K_t×[(T_env-T_set) / (m3-T_set)+m4]; in, C_t is the temperature condition judgment coefficient; K_t is the second temperature correction coefficient; T_env is the outdoor ambient temperature; T_set is the threshold for enabling ambient temperature; m3 is the third compensation constant; m3 is a positive number, for example, m3=15; m4 is the fourth compensation constant, and m4 is a positive number, for example, m4=1.

[0082] Using the above calculation formula, the temperature condition judgment coefficient C_t can be accurately calculated, and then the accurate opening judgment total coefficient C_open can be calculated.

[0083] Enable the judgment of the total coefficient C_open: C_open = C_p + C_t.

[0084] Determine whether the total coefficient C_open is greater than or equal to the coefficient threshold. For example, the coefficient threshold is 1.0.

[0085] If C_open ≥ 1.0, then the bypass valve is determined to be open; If C_open < 1.0, then the bypass valve is determined to be closed.

[0086] In some embodiments of this application, the control module is further configured to perform the following steps, see [link to relevant documentation]. Figure 11 As shown.

[0087] Step S31: Determine whether the following conditions are met: the inlet water temperature of the outdoor heat exchanger in heating mode reaches the first set water temperature threshold.

[0088] If the condition is met, i.e., the inlet water temperature of the outdoor heat exchanger in heating mode is greater than or equal to the first set water temperature threshold, then proceed to step S32 as follows: When the compressor discharge pressure is higher than the first high pressure protection threshold A1 but not higher than the second high pressure protection threshold B1, the first frequency control strategy P1 is executed on the compressor. When the compressor discharge pressure is higher than the second high pressure protection threshold B1 but not higher than the third high pressure protection threshold C1, the second frequency control strategy P2 is executed on the compressor. When the compressor discharge pressure is higher than the third high-pressure protection threshold C1, the third frequency control strategy P3 is executed on the compressor.

[0089] If the conditions are not met, proceed to step S33 below: When the compressor discharge pressure is higher than the fourth high-pressure protection threshold A2 but not higher than the fifth high-pressure protection threshold B2, the first frequency control strategy P1 is executed on the compressor. When the compressor discharge pressure is higher than the fifth high-pressure protection threshold B2 but not higher than the sixth high-pressure protection threshold C2, the second frequency control strategy P2 is executed on the compressor. When the compressor discharge pressure is higher than the sixth high-pressure protection threshold C2, the third frequency control strategy P3 is executed on the compressor.

[0090] Where A2 < A1 < B2 < B1 < C2 < C1.

[0091] The first frequency control strategy P1 is: maintain normal compressor frequency control. For example, control the compressor frequency based on the actual indoor temperature and the target indoor temperature.

[0092] The second frequency control strategy P2 is: the compressor frequency is prohibited from increasing or decreases at the first speed (slow decrease).

[0093] The third frequency control strategy P3 is: the compressor frequency decreases at a first speed (slow decrease) or at a second speed (rapid decrease). The second speed is greater than the first speed.

[0094] The fourth frequency control strategy, P4, is: increase the compressor frequency.

[0095] High inlet water temperature will cause the refrigerant temperature of the entire system to rise, which in turn will cause both the high-pressure and low-pressure of the entire unit to increase. To address the issue of excessively high pressure, the high-pressure protection control of the entire unit is differentiated based on the inlet water temperature, and different frequency control strategies are selected according to the compressor discharge pressure to ensure stable operation of the unit.

[0096] By designing steps S31 to S33, it is first determined whether the inlet water temperature of the outdoor heat exchanger in heating mode is greater than or equal to the first set water temperature threshold. If it is satisfied, the first high-pressure protection threshold A1, the second high-pressure protection threshold B1, and the third high-pressure protection threshold C1 are selected to form a threshold range. Then, according to the threshold range where the compressor discharge pressure is located, different frequency control strategies are executed to ensure the stable and normal operation of the compressor. If it is not satisfied, the fourth high-pressure protection threshold A2, the fifth high-pressure protection threshold B2, and the sixth high-pressure protection threshold C2 are selected to form a threshold range. Then, according to the threshold range where the compressor discharge pressure is located, different frequency control strategies are executed to ensure the stable and normal operation of the compressor and the entire unit.

[0097] In some embodiments of this application, the control module is further configured to perform the following steps, see [link to relevant documentation]. Figure 12 As shown.

[0098] Step S41: Determine whether the following condition is met: the inlet water temperature of the outdoor heat exchanger in heating mode reaches the first set water temperature threshold.

[0099] If the conditions are met, i.e., the inlet water temperature of the outdoor heat exchanger in heating mode is greater than or equal to the first set water temperature threshold, then step S42 is executed: when the compressor suction pressure is higher than the first low-pressure protection threshold D1, the fourth frequency control strategy P4 is executed on the compressor. That is, the compressor frequency is controlled to increase.

[0100] If the conditions are not met, then step S43 is executed: when the compressor suction pressure is higher than the second low-pressure protection threshold D2, the fourth frequency control strategy P4 is executed on the compressor. That is, the compressor frequency is controlled to increase.

[0101] Among them, the first low-voltage protection threshold D1 is greater than the second low-voltage protection threshold D2.

[0102] High inlet water temperature will cause the refrigerant temperature of the entire system to rise, which in turn will lead to an increase in the low-pressure of the entire unit. To address the issue of excessively high low-pressure, the low-pressure protection control of the entire unit is differentiated based on the inlet water temperature, and the corresponding protection threshold for low-pressure is increased to ensure stable operation of the unit.

[0103] By designing steps S41 to S43, when the inlet water temperature of the outdoor heat exchanger in heating mode is greater than or equal to the first set water temperature threshold, the first low-pressure protection threshold D1 is selected; when the inlet water temperature of the outdoor heat exchanger in heating mode is not greater than or equal to the first set water temperature threshold, the second low-pressure protection threshold D2 is selected, so as to ensure the stable and normal operation of the compressor and the entire unit.

[0104] In some embodiments of this application, the first frequency control strategy P1, the second frequency control strategy P2, and the third frequency control strategy P3 have a higher priority than the fourth frequency control strategy P4.

[0105] When the fourth frequency control strategy P4 conflicts with the first frequency control strategy P1, the second frequency control strategy P2, or the third frequency control strategy P3, the fourth frequency control strategy P4 will not be executed; instead, the first frequency control strategy P1, the second frequency control strategy P2, or the third frequency control strategy P3 will be executed.

[0106] The first frequency control strategy P1, the second frequency control strategy P2, or the third frequency control strategy P3 are high-pressure protection strategies, while the fourth frequency control strategy P4 is a low-pressure protection strategy. When the low-pressure protection strategy conflicts with the high-pressure protection strategy, the low-pressure protection strategy is not executed; instead, the high-pressure protection strategy is executed first to prevent compressor failure and ensure the normal operation of the compressor.

[0107] See Tables 1 and 2 below, where x is the first set water temperature threshold.

[0108]

[0109]

[0110] This application achieves coordinated control of the regulating valve opening and system pressure threshold of the air conditioning equipment (water source multi-split unit) using a dynamic operation control mechanism. Addressing the technical challenge of difficult operation of the heating cycle under high water temperature conditions, this application overcomes the technical bottleneck of existing water source units being unable to operate and heat under high water temperature conditions (45℃) by adjusting the regulating valve opening and linking it with the system pressure to maintain the optimal range for high water temperature environments. This ensures that the product maintains reliable heating performance over a wide range of water temperatures.

[0111] The air conditioning equipment (water source multi-split unit) of this application solves the technical problem that water source units cannot heat at high water temperatures by controlling the overall system pressure (exhaust pressure, intake pressure), the opening degree of the regulating valve (electronic expansion valve), and the opening and closing of the bypass valve (solenoid valve) of the water source multi-split unit through linkage control.

[0112] This application effectively overcomes the heating bottleneck of water source units under high water temperature conditions by coordinating and regulating the pressure of the whole system, dynamically adapting the opening of the regulating valve (electronic expansion valve), and precisely controlling the on / off state of the bypass valve (solenoid valve), ensuring that the product can stably output heating performance within a wide water temperature range, and significantly improving the environmental adaptability and operational reliability of the water source unit.

[0113] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0114] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An outdoor unit, characterized in that, include: compressor; Outdoor heat exchanger; A repeater has a first port, a second port, a third port, and a fourth port, as well as a first refrigerant passage connecting the first port and the second port, and a second refrigerant passage connecting the third port and the fourth port; the first port is connected to the liquid pipe of the indoor heat exchanger, and the second port is connected to the liquid pipe of the outdoor heat exchanger; the second port is connected to the third port through a connecting pipe, and the fourth port is connected to the suction port of the compressor; a regulating valve is provided on the connecting pipe; The control module is configured to: in heating mode, when the inlet water temperature of the outdoor heat exchanger reaches the first set water temperature threshold, open the regulating valve and adjust the opening degree of the regulating valve according to the outdoor ambient temperature and the compressor exhaust pressure.

2. The outdoor unit according to claim 1, characterized in that: The adjustment of the regulating valve opening based on the outdoor ambient temperature and compressor discharge pressure specifically includes: The water temperature compensation opening is obtained by multiplying the difference between the first compensation constant and the outdoor ambient temperature, the first temperature correction coefficient, and the current opening of the regulating valve. The pressure compensation opening is obtained by multiplying the difference between the second compensation constant and the compressor discharge pressure and the first pressure correction coefficient. The target opening of the control valve is obtained by summing the water temperature compensation opening, pressure compensation opening, and the current opening of the control valve.

3. The outdoor unit according to claim 1, characterized in that: The outdoor unit also includes: A bypass pipeline, one end of which is connected to the exhaust port of the compressor and the other end of which is connected to the intake port of the compressor, is provided with a bypass valve. The control module is also configured to: In heating mode, when the inlet water temperature of the outdoor heat exchanger reaches the second set water temperature threshold and only one indoor unit is turned on, the bypass valve is adjusted according to the outdoor ambient temperature and the compressor discharge pressure. The second set water temperature threshold is greater than the first set water temperature threshold.

4. The outdoor unit according to claim 3, characterized in that: The adjustment of the bypass valve's on / off state based on outdoor ambient temperature and compressor discharge pressure specifically includes: Calculate the pressure condition judgment coefficient based on the second pressure correction coefficient, compressor discharge pressure, and system pressure opening threshold. Based on the second temperature correction coefficient, outdoor ambient temperature, and ambient temperature opening threshold, calculate the temperature condition judgment coefficient. The sum of the pressure condition judgment coefficient and the temperature condition judgment coefficient is calculated to obtain the total opening judgment coefficient; Determine whether the total coefficient of the activation judgment has reached the coefficient threshold; If yes, the bypass valve will be opened; otherwise, the bypass valve will be closed.

5. The outdoor unit according to claim 4, characterized in that: The calculation of the pressure condition judgment coefficient based on the second pressure correction coefficient, compressor discharge pressure, and system pressure opening threshold specifically includes: C_p = K_p × (P_sys / P_set); Where C_p is the pressure condition judgment coefficient; K_p is the second pressure correction factor; P_sys is the compressor discharge pressure; P_set is the system pressure threshold.

6. The outdoor unit according to claim 4, characterized in that: The calculation of the temperature condition judgment coefficient based on the second temperature correction coefficient, outdoor ambient temperature, and ambient temperature activation threshold specifically includes: C_t=K_t×[(T_env-T_set) / (m3-T_set)+m4]; Where C_t is the temperature condition judgment coefficient; K_t is the second temperature correction coefficient; T_env is the outdoor ambient temperature; T_set is the threshold for enabling ambient temperature; m3 is the third compensation constant; m4 is the fourth compensation constant.

7. The outdoor unit according to any one of claims 1 to 6, characterized in that: The control module is also configured to: Determine if the following condition is met: In heating mode, the inlet water temperature of the outdoor heat exchanger reaches the first set water temperature threshold. If satisfied, then execute: When the compressor discharge pressure is higher than the first high-pressure protection threshold A1 but not higher than the second high-pressure protection threshold B1, the first frequency control strategy is executed on the compressor. When the compressor discharge pressure is higher than the second high-pressure protection threshold B1 but not higher than the third high-pressure protection threshold C1, the second frequency control strategy is executed on the compressor. When the compressor discharge pressure is higher than the third high-pressure protection threshold C1, the third frequency control strategy is implemented for the compressor. If not satisfied, then execute: When the compressor discharge pressure is higher than the fourth high-pressure protection threshold A2 but not higher than the fifth high-pressure protection threshold B2, the first frequency control strategy is executed on the compressor. When the compressor discharge pressure is higher than the fifth high-pressure protection threshold B2 but not higher than the sixth high-pressure protection threshold C2, the second frequency control strategy is implemented for the compressor. When the compressor discharge pressure is higher than the sixth high-pressure protection threshold C2, the third frequency control strategy is implemented for the compressor. Where A2 < A1 < B2 < B1 < C2 < C1.

8. The outdoor unit according to claim 7, characterized in that: The control module is also configured to: Determine if the following condition is met: In heating mode, the inlet water temperature of the outdoor heat exchanger reaches the first set water temperature threshold. If the conditions are met, then when the compressor suction pressure is higher than the first low-pressure protection threshold D1, the fourth frequency control strategy is executed on the compressor. If the conditions are not met, then when the compressor suction pressure is higher than the second low-pressure protection threshold D2, the fourth frequency control strategy is executed on the compressor; where D1 > D2.

9. The outdoor unit according to claim 8, characterized in that: The first frequency control strategy, the second frequency control strategy, and the third frequency control strategy have higher priority than the fourth frequency control strategy.

10. An air conditioning unit, characterized in that: Includes the outdoor unit as described in any one of claims 1 to 9.

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