Self-optimizing high-efficiency composite source air conditioner heat pump unit

Abstract

The present application relates to air conditioner heat pump machine field, especially a kind of self-optimizing high-efficiency composite source air conditioner heat pump unit, including composite heat exchanger unit, the composite heat exchanger unit includes evaporative condenser device and air side finned tube heat exchanger, the evaporative condenser device is connected with air side finned tube heat exchanger, and in refrigerant flow path is parallel arrangement, and in refrigeration direction entrance end is with regulating valve and carries out respective flow control, can be realized in refrigeration and heating operation, two kinds of heat exchanger are with independent or joint mode and put into operation.The composite heat exchanger unit still includes cooling fan, evaporative condenser device and air side finned tube heat exchanger share a cooling fan, the cooling fan is located between evaporative condenser device and air side finned tube heat exchanger, and symmetric air intake design is adopted.The present application can make evaporative condenser device and air side finned tube heat exchanger cooperate well, improve energy efficiency.

Description

Technical Field

[0001] This invention relates to the field of air conditioning heat pumps, and in particular to a self-optimizing high-efficiency composite source air conditioning heat pump unit. Background Technology

[0002] Air-cooled heat exchangers utilize the temperature difference between ambient air and the refrigerant inside the condenser for cooling in summer. They do not require cooling water, only a fan for air circulation, making them convenient to use and install. However, air-cooled condensers have a low heat transfer coefficient, and the units are relatively large and heavy, making them suitable only for applications with significant temperature differences, such as above 15°C. In winter, air-cooled heat exchangers can function as evaporators in heat pump systems, extracting heat from low-grade air heat sources—a type of energy-saving heat pump technology.

[0003] An evaporative condenser is a highly efficient heat exchanger that utilizes the heat absorbed by water evaporating outside the tubes to condense refrigerant vapor inside. Its cooling efficiency is more than 45% higher than that of an air-cooled condenser. The working principle is as follows: cooling water in the collection tank is pumped to the spray pipe and sprayed onto the outer surface of the condenser tubes through nozzles, forming a water film. Part of the water in the film absorbs heat and evaporates into water vapor, which is carried away by the air. The unevaporated water falls back into the collection tank, and a float valve replenishes the cooling water to maintain the required operating water level.

[0004] Evaporative condensation technology is widely used in closed-circuit cooling tower products. Currently, evaporative condenser products using refrigerant as the working fluid are increasingly common, primarily single-cooling evaporative chiller units. In recent years, some air conditioning manufacturers have launched new evaporative heat pump products combining evaporative condensation technology and air source heat pump technology. However, these generally suffer from immature technology, poor unit performance, lower heating performance compared to conventional air conditioning heat pumps, and low unit reliability. Currently, heat pump units are of two types: one uses an air-source finned tube heat exchanger for heating, and the other directly utilizes an evaporative condenser by adding antifreeze solution to the cooling water. In the former approach, the evaporative condenser and finned tube heat exchanger are independent units. The evaporative condenser is used in summer, and the finned tube heat exchanger is used in winter, resulting in idle heat exchangers. Furthermore, the heat exchanger's internal volume is too large, requiring a large refrigerant charge and necessitating special design to prevent compressor oil loss. Additionally, the unit is large and expensive. The latter option is unsuitable for evaporative condensers because evaporative condensers are not well-suited for evaporation applications. The condenser consists of serpentine tube bundles with large diameters and no extended fins, making it unsuitable for use as an evaporator. The condenser is made of plates or plate-tubes, using 1.5mm steel plates folded in half and spot-welded to form flow channels, followed by hot-dip galvanizing for corrosion protection. Although this reduces the heat exchange flow channels, the flow channel cross-section lacks efficient heat exchange design features, requiring the use of antifreeze. The heating effect is poor when the ambient temperature is below 5℃, and it cannot achieve continuous 24-hour heating. It is only suitable for use in the hot-summer, warm-winter South China region. Summary of the Invention

[0005] The purpose of this invention is to provide a self-optimizing high-efficiency composite source air conditioning heat pump unit that can effectively coordinate the evaporative condenser device and the air-side finned tube heat exchanger to improve energy efficiency.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A self-optimizing high-efficiency composite source air conditioning heat pump unit includes a composite heat exchanger unit, which includes an evaporative condenser device and an air-side finned tube heat exchanger. The evaporative condenser device and the air-side finned tube heat exchanger are arranged in parallel in the refrigerant flow path, and their respective flow rates are controlled by regulating valves at the inlet end in the cooling direction. This allows the two heat exchangers to operate independently or in combination during cooling and heating operations.

[0008] The composite heat exchanger unit also includes a cooling fan. The evaporative condenser and the air-side finned tube heat exchanger share a cooling fan, which is located between the evaporative condenser and the air-side finned tube heat exchanger and adopts a symmetrical air intake design.

[0009] It also includes a compressor, a four-way reversing valve, and a liquid receiver. The discharge end of the compressor is connected to the four-way reversing valve. The inlet end of the branch where the evaporative condenser unit and the air-side finned tube heat exchanger are located is connected to the condenser interface end of the four-way reversing valve. The outlet end of the evaporative condenser unit and the air-side finned tube heat exchanger are connected to the inlet pipe of the liquid receiver, forming a parallel arrangement in the flow path.

[0010] It also includes regulating valve A, check valve I, solenoid valve, check valve VI and auxiliary throttling device, and the branch connected to the evaporative condenser unit, which, in the refrigeration flow direction, passes through regulating valve A, evaporative condenser unit and check valve I in sequence.

[0011] The branch connected to the evaporative condenser unit, in the heating direction, passes through the solenoid valve, auxiliary throttling device, check valve VI, evaporative condenser unit, and regulating valve A in sequence.

[0012] It also includes regulating valve B, check valve II and check valve V, and a branch connected to the air-side finned tube heat exchanger. In the refrigeration flow direction, it passes through regulating valve B, air-side finned tube heat exchanger and check valve II in sequence.

[0013] The branch connected to the air-side finned tube heat exchanger, in the heating direction, passes through the one-way valve V, the air-side finned tube heat exchanger, and the regulating valve B in sequence.

[0014] When the unit is in cooling operation, it automatically selects three modes: evaporative cooling, air cooling, and combined cooling to match efficient operation under all working conditions.

[0015] When the unit is cooling, the automatic selection of the operating state depends on the ambient wet-bulb temperature parameter, which is obtained through the wet-bulb temperature calculation module of the controller. The ambient relative humidity parameter required for the calculation comes from the relative humidity sensor configured in the unit, or from the weather humidity data in the weather forecast on the network through the smart gateway configured in the unit.

[0016] When the unit is in heating mode, it operates as an air source heat pump. When the heating performance decreases due to the drop in ambient temperature, it can automatically engage the evaporative condenser unit to enhance the operation. The evaporative condenser unit can be used as a heating evaporator. At the same time, heating can be carried out by solution heating or air-cooled heat exchanger evaporative heat exchange.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] 1. Compared with traditional air source heat pump units, it significantly improves the energy efficiency during cooling, by more than 40%.

[0019] 2. Compared with conventional composite source heat pump units, it adopts a high-efficiency plate evaporative condenser, and during cooling operation, it automatically optimizes to ensure that the unit operates in a high-efficiency state under all operating conditions, and the overall energy efficiency can be improved by more than 15%.

[0020] 3. Compared with conventional composite source heat pump units, it adds air-cooled cooling mode and composite cooling mode, expanding the unit's cooling operation range. The lower limit of the unit's cooling ambient temperature can be reduced from 15℃ of conventional units to 5℃, and the maximum wet-bulb temperature of the evaporative cooling unit can be extended from 30℃ to 38℃.

[0021] 4. Compared with conventional composite source heat pump units, an air-cooled mode has been added, with air-cooled cooling as a backup option, improving the reliability and redundancy of the system design.

[0022] 5. Compared with conventional composite source heat pump units, the evaporative condenser is no longer idle and wasted during heating operation. It can be used as an auxiliary evaporator, increasing the heat exchange area of ​​the evaporator by more than 15%, raising the evaporation temperature, and improving the heating operation efficiency by more than 5%.

[0023] 6. Compared with conventional composite source heat pump units, the air-side finned tube heat exchanger and evaporative condenser share the same air system, resulting in a more compact, aesthetically pleasing, and space-saving unit structure.

[0024] 7. Compared with conventional hybrid heat pump units, the air-side finned tube heat exchanger and evaporative condenser share the same air system, reducing the number of fans required. Simultaneously, the evaporative condenser's heat exchange channels are small-scale, reducing refrigerant charge by 20% and lowering unit design costs.

[0025] 8. Compared with existing heat pump units of various types, it has significant advantages in energy efficiency and environmental protection, and is a green and low-carbon product. Attached Figure Description

[0026] Figure 1 This is a flowchart of a self-optimizing, high-efficiency composite source air conditioning heat pump unit system;

[0027] Figure 2 This is a schematic diagram of the input and output of the control device for a composite source heat pump system;

[0028] Figure 3 This is a flowchart of the decision-making process for the refrigeration operation mode;

[0029] Figure 4 This is the automatic optimization logic diagram for the cooling operation mode;

[0030] Figure 5 This is a schematic diagram of a self-optimizing, high-efficiency composite source air conditioning heat pump unit.

[0031] Figure 6 and Figure 7 This is a structural diagram of a cooling fan;

[0032] Figure 8 This is a schematic diagram of the circular tube frame structure;

[0033] Figure 9 This is a schematic diagram of the mesh structure;

[0034] Figure 10 This is a schematic diagram of the rotating plate.

[0035] Figure 11 This is a cross-sectional view of the rotating plate.

[0036] Figure 12 yes Figure 11 A partially enlarged structural diagram.

[0037] In the picture:

[0038] 1-Compressor; 2-Combined heat exchanger unit; 2a-Evaporative condenser unit; 2b-Air-side finned tube heat exchanger; 2c-Cooling fan; 3-Use-side heat exchanger; 4-Throttling device; 5-Four-way reversing valve; 6-Liquid receiver; 7-Dryer filter; 8-Vacuum-liquid separator; 9-Regulating valve A; 10-Regulating valve B; 11-Check valve I; 12-Check valve II; 13-Check valve III; 14-Check valve IV; 15-Check valve V; 16-Solenoid valve; 17-Check valve VI; 18-Auxiliary throttling device; 2 a1-Evaporative condenser; 2a2-Cooling water tank; 2a3-Cooling water pump; 2a4-Spray water device; 2a5-Heat dissipation packing; 2a6-Float water supply valve; 2a7-Water treatment device; 2a8-Drain valve; 2001-Circular tube frame; 2002-Connecting ring; 2003-Annular gap; 2004-Inner plate; 2005-Partition mesh; 2006-Annular plate; 2007-Rotating plate; 2008-Intermediate tube; 2009-Partition plate; 2010-Drain hole; 2011-Rhomboid plate and 2012-Through hole; Detailed Implementation

[0039] like Figure 1-5 As shown, a detailed description of the self-optimizing high-efficiency composite source air conditioning heat pump unit is provided:

[0040] A self-optimizing, high-efficiency composite source air conditioning heat pump unit comprises a compressor 1, a composite heat exchanger unit 2, a user-side heat exchanger 3, a throttling device 4, a four-way reversing valve 5, a liquid receiver 6, a dryer filter 7, a vapor-liquid separator 8, regulating valve A 9, regulating valve B 10, 11-one-way valve I; 12-one-way valve II; 13-one-way valve III; 14-one-way valve IV; 15-one-way valve V; 16-solenoid valve; 17-one-way valve VI; 18-auxiliary throttling device, and piping and control devices. The system flow diagram is described below. Figure 1 .

[0041] The composite heat exchanger unit 2 comprises an air-side finned tube heat exchanger 2b, an evaporative condenser unit 2a, and a cooling fan 2c. The evaporative condenser unit 2a mainly consists of an evaporative condenser 2a1, a cooling water tank 2a2, a cooling water pump 2a3, a spray water device 2a4, heat dissipation packing 2a5, a float-type water supply valve 2a6, a water treatment device 2a7, and a drain valve 2a8. The cooling fan 2c is a shared fan for both the finned tube heat exchanger 2b and the evaporative condenser unit 2a. Structurally, the fan is centrally located, with the finned tube heat exchanger 2b and the evaporative condenser unit 2a located on either side. When the fan is on, air enters both heat exchangers simultaneously. This non-series airflow layout significantly reduces the fan's operating resistance. The shared airflow system reduces the number of fans, making the unit structure more compact and lowering design costs. The air-source finned tube heat exchanger 2b and the evaporative condenser 2a1 are arranged in parallel on the refrigerant flow path, so that they can operate independently or in combination when acting as condensers and evaporators during cooling and heating operations, thereby achieving the effects of enhanced heat exchange and mutual backup.

[0042] Among them, the evaporative condenser 2a1 is designed as a plate condenser, constructed using high-efficiency brazed plate heat exchange substrates. Based on the formula for the refrigerant evaporation-convective heat transfer coefficient within the heat exchange tubes...

[0043]

[0044] The heat transfer coefficient αi is inversely proportional to the 0.6 power of the tube inner diameter di, meaning that choosing a smaller tube inner diameter di can improve evaporative heat transfer performance. Following this principle, the plate heat exchanger channel is designed with a small-scale flow cross-section, with an equivalent diameter less than 5.0 mm. This smaller flow cross-section compared to commonly used tube bundle heat exchanger tube diameters and wall thicknesses of φ25*1.5 mm, φ18*1.0 mm, φ16*1.0 mm, φ12.7*0.8 mm, and φ9.52*0.5 mm results in superior evaporative heat transfer performance, being 2.3 times that of φ25, 2.0 times that of φ18, and 1.3 times that of φ9.52. Simultaneously, the smaller internal volume—reducing it by 50% compared to the φ9.52 tube bundle type—significantly reduces refrigerant charge and compressor lubricant retention, greatly enhancing the efficiency and reliability of the evaporative condenser as a heat pump evaporator. To further enhance heat exchange characteristics, the internal and external flow channels of the heat exchange plates have undergone enhanced heat transfer design. To adapt to the corrosive environment of evaporative cooling, the plates are made of SUS316L stainless steel, which offers superior atmospheric corrosion resistance compared to SUS304, copper tubes, and hot-dip galvanized carbon tubes. To ensure welding quality and improve production efficiency, CNC molds were developed, and vacuum brazing was employed to achieve stable mass production. As a result, the plates feature excellent heat transfer performance, high pressure resistance, corrosion resistance, and high production efficiency. They are compact in size, have a small internal volume, and can withstand pressures up to 4.5 MPa, making them ideal for heat pump applications.

[0045] The system includes regulating valves A9 and B10 to enable evaporative cooling, air cooling, and a combination of both. This allows the evaporative condenser to function as an evaporator in the combined heat pump unit. Both regulating valves have adjustable flow cross-sections, with the adjustment signal originating from a control device. This allows for operational control of the finned tube heat exchanger 2b and the evaporative condenser 2a1. By controlling the flow rate, the load distribution between the two heat exchangers is adjusted, making efficient unit operation possible. During cooling operation, when regulating valve A9 is open and regulating valve B10 is closed, evaporative cooling is used for condensation and heat dissipation. When regulating valve A9 is closed and regulating valve B10 is open, air cooling is used for condensation and heat dissipation. When both regulating valves are open, either of the above two cooling methods applies. When the combined source heat pump unit is in heating mode, when the regulating valve A9 is closed and the regulating valve B10 is opened, the air-side finned tube heat exchanger 2b operates as an evaporator, thus becoming an air source heat pump heating mode; when equipped with solenoid valve 16 and one-way valve VI17 branch, if the regulating valve A9 is opened, the evaporative condenser 2a1 can also be used as an evaporator.

[0046] For the design method of the controller input / output of the control device, please refer to [link / reference]. Figure 2 The unit is equipped with a dedicated relative humidity sensor and an IoT smart gateway. By combining signals from the unit's own sensors with remote commands, the controller calculates the wet-bulb temperature, which is then used as a crucial parameter for cooling mode control. The collected exhaust pressure sensor readings are used by the controller to calculate the corresponding saturation temperature, which is also listed as a critical parameter for cooling mode control. The addition of an IoT smart gateway allows the control unit to receive external control commands and information, such as ambient temperature and humidity information from local weather forecasts downloaded via a mobile app. This enables units without a dedicated relative humidity sensor, or those with a malfunctioning relative humidity sensor, to receive external relative humidity signals to maintain normal controller operation and decision-making.

[0047] The cooling mode can be expanded from the conventional single evaporative cooling mode to three modes: evaporative cooling, air cooling, and a combined cooling mode. Evaporative cooling is the most efficient and is the primary cooling mode. Air cooling can be used as a backup for evaporative cooling. When the outdoor ambient temperature is low and the system condensing temperature can be controlled below 38°C, air cooling can be used. When high system efficiency is achieved, the cooling water system can be left undisturbed, avoiding power consumption by the cooling water pump, increasing system reliability, and extending the lifespan of the cooling water pump. When outdoor relative humidity is high, such as above 85%, or wet-bulb temperature is high, such as above 30℃, evaporative cooling driven by air enthalpy difference is less efficient, resulting in poor cooling effect, high compressor discharge pressure, and persistently high system condensing temperature, leading to high power consumption and energy inefficiency, while also affecting unit reliability. In such cases, an air-cooling mode can be added to the existing evaporative cooling mode, operating in a combined cooling mode to share the condensing heat load, effectively reducing the system condensing temperature. In high humidity environments, this can reduce the condensing temperature by more than 4℃, improving compressor efficiency by more than 12%, while reversing the original high condensing temperature operating conditions of the compressor and ensuring its reliability. Therefore, in the cooling operation of a combined source heat pump unit, the addition of air-cooling mode can improve or guarantee high-efficiency operation of the unit, ensure its reliability, and expand its operating range. The lower limit of the unit's cooling ambient temperature can be lowered from 15℃ for conventional units to 5℃, and the maximum wet-bulb temperature of the evaporative cooling unit can be extended from 30℃ to 38℃.

[0048] During refrigeration operation, the exhaust from compressor 1 flows through four-way reversing valve 5 to the inlet of regulating valves A9 and B10. If the unit controller determines that evaporative cooling mode is used, regulating valve A9 is open and regulating valve B10 is closed. Components of the evaporative condenser unit, such as cooling water pump 2a3 and cooling fan 2c, are put into operation. The unit operates in a high-efficiency evaporative cooling mode. The refrigerant flows successively through check valve I11, receiver 6, dryer filter 9, throttling device 4, check valve III13, user-side heat exchanger 3, four-way reversing valve 5, and vapor-liquid separator 8 before returning to the suction port of compressor 1, thus completing the classic mechanical compression refrigeration cycle. During refrigeration operation, if the unit controller determines that air-cooled cooling mode is used, regulating valve A9 is closed and regulating valve B10 is open. The unit operates in an air-cooled mode. The refrigerant flows successively through check valve II12 and receiver 6, and the subsequent flow is the same as described above. When the unit controller determines that it is in the combined cooling mode, regulating valve A9 and regulating valve B10 are in the open state. During normal operation, regulating valve A9 is fully open, and regulating valve B10 adjusts its opening degree according to the system condensing temperature.

[0049] During heating operation, the exhaust gas from compressor 1 flows through four-way reversing valve 5 to the user-side heat exchanger 3 for condensation and heat dissipation to heat the user-side fluid. After condensation, it flows through one-way valve IV14, liquid receiver 6, and dryer filter 9. After being throttled by throttling device 4 into low-pressure, low-temperature refrigerant, it flows through one-way valve V15 into air-side finned tube heat exchanger 2b. After absorbing heat from the ambient air, it becomes superheated gas and then flows to regulating valve B10, four-way reversing valve 5, and vapor-liquid separator 8 before finally returning to the compressor 1 suction port, completing the heating process. This is the classic heating operation of an air source heat pump system.

[0050] During heating operation, when equipped with solenoid valve 16 and one-way valve VI 17, opening solenoid valve 16 and regulating valve A9 allows the evaporative condenser 2a1 to function as an evaporator, helping to alleviate the significant performance degradation of traditional air-source heat pump units caused by frost accumulation. With the evaporative condenser 2a1 used as an evaporator, the evaporator area of ​​the unit is increased compared to the air-side finned tube heat exchanger 2b, expanding the heat exchange area by more than 15%, sharing some of the evaporator load, increasing the system evaporation pressure, and raising the evaporation temperature by more than 1.5℃, thereby improving operating efficiency by more than 5%. When the evaporative condenser 2a1 is used as an evaporator, the activation of the cooling water pump 2a3 is determined by monitoring the outdoor ambient temperature and cooling water temperature. When the cooling water pump 2a3 is activated, spray water is applied to the surface of the evaporative condenser 2a1, the refrigerant absorbs heat from the water film, and the flowing air releases heat to the water film, providing its heat source, thus achieving solution heating. The optimization of the heating mode is mainly aimed at the fact that the heating performance of the air source heat pump will decrease when the ambient temperature is below 15℃. The decision to put the evaporative condenser 2a1 into operation to improve efficiency is based on the system operating status. For example, if the current operating evaporation temperature is less than the ambient temperature -13℃, it indicates that the current heating performance is poor. The evaporative condenser device 2a can be put into operation to increase the heat exchange area and improve the evaporation temperature.

[0051] During the unit's heating and defrosting operation, the classic refrigeration reverse cycle defrosting method is adopted. During heating operation, the four-way reversing valve 5 is used to switch the compressor 1 exhaust to the air-side finned tube heat exchanger 2b or the evaporative condenser 2a1 for heating and defrosting.

[0052] Among them, the composite source air conditioning heat pump unit can be controlled to operate automatically and efficiently through the unit controller's self-optimization decision module. During cooling operation, its main optimization execution process is described in [link to relevant documentation]. Figure 3As shown, after initially optimizing the operating mode, further adjustments are needed based on the unit's operating status to ensure optimal unit performance in case of sensor errors or malfunctions in system components. During cooling operation, the unit is designed with two modes: automatic cooling and manual selection. The manual selection mode offers three options: evaporative cooling, air cooling, and a hybrid cooling system, allowing users to choose freely based on site conditions. When automatic cooling mode is selected, the system uses weather parameters transmitted via a mobile app or ambient temperature and humidity parameters collected by the unit's sensors, combined with the set condensing temperature energy-saving point value, to comprehensively determine the appropriate cooling mode. The specific decision-making process is as follows: Figure 9 As shown, in automatic cooling mode, if the relative humidity is greater than 90% and the wet-bulb temperature is greater than 35℃, it indicates that evaporative cooling is ineffective, or the unit is operating in a high-humidity environment where condensation is unfavorable. In this case, it is necessary to switch to air-cooled or combined cooling mode to enhance cooling capacity and reduce the system condensing temperature. When automatically selecting between evaporative cooling, air-cooled cooling, and combined cooling modes, a condensing temperature energy-saving point needs to be set as a judgment parameter. This parameter is then compared with the calculated condensing temperatures for evaporative cooling and air-cooled cooling to determine which operating mode to use. The condensing temperature energy-saving point parameter is a fixed input value or can be set according to ambient temperature zones. The calculated evaporative cooling condensing temperature = wet-bulb temperature + 13℃. The wet-bulb temperature can be calculated using known dry-bulb temperature, relative humidity, and atmospheric pressure parameters. Atmospheric pressure is the meteorological parameter of the installation location and can be pre-input. Dry-bulb temperature and relative humidity are parameters collected by the unit's sensors or input from weather forecast parameters downloaded from a mobile app. The calculated air-cooled cooling condensing temperature = dry-bulb temperature + 15℃. The proper functioning of the cooling water delivery system is determined by checking whether the cooling water level is adequate and whether the cooling water pump is functioning correctly.

[0053] This solution allows for interchangeable operation of evaporative cooling and air cooling, with air cooling serving as a backup option to improve system reliability and design redundancy. In the event of an evaporative condenser failure or when maintenance is required, the system can be switched to air cooling mode to ensure continuous operation of the unit.

[0054] The implementation principle of this invention:

[0055] like Figure 1-5As shown, a self-optimizing high-efficiency composite air conditioning heat pump unit comprises a compressor 1, a composite heat exchanger unit 2, a user-side heat exchanger 3, a throttling device 4, a four-way reversing valve 5, a liquid receiver 6, a dryer filter 7, a vapor-liquid separator 8, a regulating valve A9, a regulating valve B10, a solenoid valve 16, one-way valves I11-17, an auxiliary throttling device 18, and piping and control devices. The composite heat exchanger unit 2 consists of an air-side finned tube heat exchanger 2b, an evaporative condenser unit 2a, and a cooling fan 2c. The evaporative condenser unit 2a mainly consists of an evaporative condenser 2a1, a cooling water tank 2a2, a cooling water pump 2a3, and other auxiliary components. The cooling fan 2c is a shared fan for the finned tube heat exchanger 2b and the evaporative condenser unit 2a, positioned between the two heat exchangers with air intakes on both sides, and the channel resistance is matched in the design. Regulating valve A9 can be selected as an electric valve or a solenoid valve, which only controls on / off states. Regulating valve B10 is selected as a 0-10V actuator self-regulating flow control valve, which can control the opening degree. The D port of the four-way reversing valve 5 is connected to the compressor exhaust, the E port of the four-way reversing valve 5 is connected to the user-side heat exchanger 3, the S port of the four-way reversing valve 5 is connected to the vapor-liquid separator 8, and the C port of the four-way reversing valve 5 is connected to the ports of regulating valves A9 and B10, and then to the evaporative condenser 2a1 and the air-side finned tube heat exchanger 2b. The evaporative condenser 2a1 and the air-side finned tube heat exchanger 2b are arranged in parallel in the refrigerant flow path, and the flow is controlled by the regulating valve, which easily achieves heat exchange enhancement and mutual backup effects. To match the evaporative condenser 2a1 as a heating evaporator, an auxiliary throttling device 18 is set up for flow rematch. The auxiliary throttling device can be a thermal expansion valve, an orifice plate, or an electronic expansion valve. When it is an electronic expansion valve, the solenoid valve 16 can be omitted.

[0056] When the unit is in cooling operation, the cooling mode command is issued by the controller based on manual or automatic optimization by the evaporative condenser device. When the evaporative cooling mode is adopted, the four-way reversing valve 5 is de-energized, the regulating valve A9 is fully open, the regulating valve B10 is closed, the cooling water pump 2a3 and the cooling fan 2c are put into operation, and the exhaust gas of the compressor 1 is guided by the regulating valve A9 to the evaporative condenser 2a1 for efficient cooling by evaporation and condensation. After the high-temperature and high-pressure refrigerant gas is cooled into liquid, it is introduced into the liquid receiver 6 through the one-way valve I11, and after passing through the dryer filter 7, it enters the throttling device 4 for throttling, pressure reduction and temperature reduction. The low-temperature and low-pressure refrigerant two-phase fluid formed by throttling enters the heat exchanger 3 on the user side for heat exchange, absorbs heat and becomes superheated gas, and is guided by the S port of the four-way reversing valve 5 to the vapor-liquid separator 8. Finally, it is drawn into the compressor 1, compressed and discharged, completing one refrigeration cycle. When switching from evaporative cooling to air cooling mode, regulating valve B10 opens, and a portion of the compressor exhaust flows to the air-side finned tube heat exchanger 2b for condensation. Then, regulating valve A9 closes, and cooling water pump 2a3 shuts down, achieving traditional air cooling operation. When switching from evaporative cooling to a combined cooling mode, regulating valve B10 opens to its initial position, and then adjusts its opening based on the current system condensing temperature. The unit operates in a combined evaporative cooling mode and air cooling mode.

[0057] When the unit is in cooling operation, the optimal condensing temperature energy-saving point is determined based on the ambient temperature conditions and compressor operating characteristics, and is set according to the ambient temperature zone. The values ​​are shown in the table below. At the refrigeration design operating point, 37℃ is taken as the condensing temperature energy-saving point.

[0058] Ambient temperature / °C Ambient temperature <30 30≤Ambient temperature<38 Ambient temperature ≥38 Condensation temperature node / °C 33 37 39.5

[0059] When the unit is operating in cooling mode, after the optimization process executes the determined operating mode, it is necessary to track the actual operating status of the unit and make appropriate adjustments. To avoid frequent switching after determining the cooling mode during the optimization process, a 2°C control zone needs to be set. For example, if the calculated condensing temperature for evaporative cooling mode is 36°C, and this is compared to the energy-saving condensing temperature point of 37°C, the unit enters the evaporative cooling operating mode. Even if the actual condensing temperature reaches 39°C after the unit starts operating, the evaporative cooling mode is still executed. If switching to another mode is required during the optimization process, and the other mode is not allowed, the current operating mode remains unchanged. If the actual condensing temperature of the unit exceeds the judgment point +2°C during the optimization process, mode correction is required. For example, if the current mode is evaporative cooling and the current compressor condensing temperature is 40°C, a combined cooling mode needs to be entered to enhance the unit's condensing heat dissipation capacity.

[0060] When the unit is in heating mode, it first starts operating as an air source heat pump. Regulating valve A9 is closed, and regulating valve B10 is fully open. Cooling fan 2c and air-side finned tube heat exchanger 2b are activated. The four-way reversing valve 5 is energized to switch the exhaust flow direction. The exhaust from compressor 1 is directed to the air-side heat exchanger 3 for cooling. After the high-temperature, high-pressure refrigerant gas is cooled into a liquid, it is introduced into the receiver 6 via check valve IV14. After passing through the dryer filter 7, it enters the throttling device 4 for throttling, pressure reduction, and temperature reduction. The low-temperature, low-pressure refrigerant two-phase fluid formed by throttling enters the air-side finned tube heat exchanger 2b via check valve V15 for heat exchange. After absorbing heat from the air, it becomes superheated gas and flows through regulating valve B10 to the S port of the four-way reversing valve 5, which directs it to the vapor-liquid separator 8. Finally, it is drawn into compressor 1 for compression and work before being discharged, completing one heating cycle.

[0061] When the unit is in heating operation, the evaporative condenser 2a is generally in the off state. It is activated based on continuous monitoring of the system's low pressure, ambient temperature, and cooling water temperature. Activation of the condenser increases the system's low pressure during low ambient temperature heating, improving heating efficiency. When activating the condenser, regulating valve A9 and solenoid valve 16 are opened, and auxiliary throttling device 18 is used for flow matching. The evaporative condenser 2a operates in two modes during heating: solution heating mode and conventional air-cooled heat exchanger evaporative heat exchange mode. In solution heating mode, the cooling water pump needs to be turned on for spraying water distribution. The activation conditions are: when the ambient temperature is between 10℃ and 21℃, and the compressor evaporation temperature is between -13℃ and the ambient temperature, and the cooling water level is normal, the cooling water pump, regulating valve A9, solenoid valve 16, and auxiliary throttling device 18 can be activated. Solution heating mode is deactivated when the ambient temperature is below 5℃, the cooling water temperature is below 3℃, or there is an abnormality in the cooling water supply. In solution heating mode, if antifreeze is added to the cooling water, its operating range can be appropriately extended as long as the cooling water side does not freeze, such as by lowering the ambient temperature and cooling water temperature. In conventional air-cooled heat exchanger evaporative heat exchange mode, as long as the ambient temperature is <21℃ and the compressor evaporation temperature during heating operation is <ambient temperature -13℃, the regulating valve A9, solenoid valve 16, and auxiliary throttling device 18 can be opened to allow the air-cooled heat exchanger to absorb heat through evaporation.

[0062] During heating defrosting operation, the unit employs a classic reverse-cycle defrosting method. In heating mode, the four-way reversing valve 5 switches the direction of compressor 1 exhaust to either the air-side finned tube heat exchanger 2b or the evaporative condenser 2a1 for heating and defrosting. If the surface temperature of either heat exchanger reaches the defrosting exit condition when defrosting exits, the regulating valve on its flow branch is closed. The regulating valve on the closed branch is reopened when the other heat exchanger exits defrosting. If the unit is currently in solution heating mode and enters defrosting mode, the cooling water pump stops and restarts after defrosting ends and the conditions are met.

[0063] like Figure 6-12 As shown, the cooling fan 2c is described in detail:

[0064] The cooling fan 2c includes a circular tube frame 2001, a connecting ring 2002, an annular gap 2003, an inner plate 2004, a mesh 2005, an annular plate 2006, a rotating plate 2007, a middle tube 2008, a partition plate 2009, a perforation 2010, a rib plate 2011, and a through hole 2012. The lower end of the circular tube frame 2001 is fixed with the connecting ring 2002, and the upper end of the circular tube frame 2001 is fixed with the mesh 2005. An annular gap 2003 is provided in the middle of the circular tube frame 2001, and the lower end of the annular gap 2003 is fixed with the inner plate 2004. A fan motor is installed at the center of the inner plate 2004, and the output shaft of the fan motor passes through the inner plate 2004. The middle tube 2008 is sleeved on... A rotating plate 2007 is fixed to the lower end of the intermediate tube 2008 on the output shaft of the fan motor. An annular plate 2006 is fixed to the outer end of the rotating plate 2007. The annular plate 2006 rotates within the annular gap 2003. Four partitions 2009 are evenly fixed between the annular plate 2006 and the intermediate tube 2008. The lower ends of the four partitions 2009 are all fixedly connected to the rotating plate 2007. Four rows of holes 2010 are evenly provided on the annular plate 2006. The four partitions 2009 extend outward to one end of the four rows of holes 2010. Multiple ribs 2011 are provided on the rotating plate 2007 between two adjacent partitions 2009. Each of the multiple ribs 2011 has a through hole 2012.

[0065] The circular tube frame 2001 is installed between the evaporative condenser and the finned tube heat exchanger via a connecting ring 2002. When the fan motor is started, it drives the rotating plate 2007 to rotate at high speed, and during the rotation, the air above the rotating plate 2007 is discharged upward and to the sides. At the same time, the air inside and below the circular tube frame 2001 is drawn to the top of the rotating plate 2007 through multiple through holes 2012, thereby forming an airflow and dissipating heat from the evaporative condenser and the finned tube heat exchanger. The air above the rotating plate 2007 is discharged upward through the partition 2005, and the air above the rotating plate 2007 is discharged to the sides through the exhaust holes 2010.

[0066] The partition net 2005 protects the internal structure of the circular tube frame 2001. Since the circular tube frame 2001 is mostly vertically installed, rain and snow can enter the circular tube frame 2001 through the partition net 2005 during rainy or snowy weather, easily causing damage. The rotating plate 2007 acts as a partition to prevent rain and snow from entering the lower part of the circular tube frame 2001. Furthermore, by providing through holes 2012 inside the rib plate 2011, with the opening of the through holes 2012 above the rotating plate 2007 being sideways, the rotation plate 2007 is protected. While allowing air to circulate downwards, this design prevents rain and snow from passing over the rotating plate 2007 through the through-hole 2012. Furthermore, when the rotating plate 2007 rotates, the opening direction of the through-hole 2012 is opposite to the direction of rotation, facilitating airflow from bottom to top and further preventing rain and snow from entering the through-hole 2012. Simultaneously, after rain and snow fall onto the rotating plate 2007, as the rotating plate 2007 rotates, the rain and snow will accumulate at the partition 2009 and be discharged through the side drain hole 2010 due to centrifugal force, thus preventing rain and snow from accumulating on the rotating plate 2007 and ensuring the isolation effect of the rotating plate 2007.

Claims

1. A high-efficiency composite source air conditioning heat pump unit, characterized in that: The system includes a composite heat exchanger unit, which comprises an evaporative condenser device and an air-side finned tube heat exchanger. The evaporative condenser device and the air-side finned tube heat exchanger are arranged in parallel on the refrigerant flow path, and each is controlled by a regulating valve at the inlet end in the refrigeration direction. This allows the two heat exchangers to operate independently or in combination during refrigeration and heating operations. The composite heat exchanger unit also includes a cooling fan. The evaporative condenser device and the air-side finned tube heat exchanger share a cooling fan. The cooling fan is located between the evaporative condenser device and the air-side finned tube heat exchanger and adopts a symmetrical air intake design. The unit also includes a compressor, a four-way reversing valve, and a liquid receiver. The discharge end of the compressor is connected to the four-way reversing valve. The inlet end of the branch where the evaporative condenser unit and the air-side finned tube heat exchanger are located is connected to the condenser interface end of the four-way reversing valve. The outlet end of the evaporative condenser unit and the air-side finned tube heat exchanger are connected to the inlet pipe of the liquid receiver, forming a parallel arrangement in the flow path. The unit also includes regulating valve A, check valve I, solenoid valve, check valve VI, and auxiliary throttling device. The branch connected to the evaporative condenser unit passes through regulating valve A, evaporative condenser unit, and check valve I in sequence when the cooling flow is in the heating flow. The unit also includes regulating valve B, check valve II, and check valve V. The branch connected to the air-side finned tube heat exchanger passes through regulating valve B, the air-side finned tube heat exchanger, and check valve II in sequence when the flow is in the cooling direction; the branch connected to the air-side finned tube heat exchanger passes through check valve V, the air-side finned tube heat exchanger, and regulating valve B in sequence when the flow is in the heating direction.

2. The high-efficiency composite source air conditioning heat pump unit according to claim 1, characterized in that: The branch connected to the air-side finned tube heat exchanger, in the heating direction, passes through the one-way valve V, the air-side finned tube heat exchanger, and the regulating valve B in sequence.

3. The high-efficiency composite source air conditioning heat pump unit according to claim 2, characterized in that: When the unit is in cooling operation, it automatically selects three modes: evaporative cooling, air cooling, and combined cooling to match efficient operation under all working conditions.

4. The high-efficiency composite source air conditioning heat pump unit according to claim 3, characterized in that: When the unit is cooling, the automatic selection of the operating state depends on the ambient wet-bulb temperature parameter, which is obtained through the wet-bulb temperature calculation module of the controller. The ambient relative humidity parameter required for the calculation comes from the relative humidity sensor configured in the unit, or from the weather humidity data in the weather forecast on the network through the smart gateway configured in the unit.

5. The high-efficiency composite source air conditioning heat pump unit according to claim 4, characterized in that: When the unit is in heating mode, it operates as an air source heat pump. When the heating performance decreases due to the drop in ambient temperature, it can automatically engage the evaporative condenser unit to enhance the operation. The evaporative condenser unit can be used as a heating evaporator. At the same time, heating can be carried out by solution heating or air-cooled heat exchanger evaporative heat exchange.

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