Efficient air source heat pump station house system

Abstract

The invention relates to the technical field of energy-saving, carbon-reducing and low-energy-consumption buildings, in particular to an efficient air source heat pump station room system which comprises an intelligent control system, an air source heat pump system, a circulating pump set, a constant-pressure water replenishing vacuum degassing unit, a decontamination system, a water softening system, pipelines and valves, the high-performance air source heat pump unit is managed through the intelligent control system to produce cold and heat in a partitioned and batched mode, and the cold and heat are supplied to an air conditioner or a heating tail end through the integrated high-efficiency circulating pump set through a low-resistance pipeline and a valve arranged in the system. In order to ensure long-term, stable and reliable operation of the system, cold and hot water passes through a decontamination system and a constant-pressure water replenishing vacuum degassing unit after being used at the tail end and before returning to the unit, and by means of a series of innovative means such as system partitioning, arrangement of partition matched electric valves and interlocking with a heat pump unit and a water pump, energy-saving and carbon-reducing operation is achieved, and energy conservation and emission reduction are achieved. And the system is subjected to refined operation adjustment according to partitions.

Description

Technical Field

[0001] The present invention relates to the technical field of energy-saving, carbon-reducing and low-energy-consumption buildings, and in particular to a high-efficiency air source heat pump station system. Background Art

[0002] Air conditioning system energy consumption is one of the main energy consumptions in my country's buildings. Data show that building energy consumption accounts for about 30% of the total social energy consumption, and air conditioning energy consumption accounts for about 65% of building energy consumption. Among them, air conditioning station energy consumption accounts for 50% to 70% of the total energy consumption of the air conditioning system. It is imperative to reduce the overall energy consumption of air conditioning stations and improve the overall energy efficiency level, which is of great significance to energy conservation and emission reduction.

[0003] In the construction industry, heat pump technology can be applied to heating, cooling and hot water supply for new buildings and renovation of existing buildings. Among them, there are various heat sources that can be used for building heating, including gas boilers, coal-fired boilers, oil boilers, electric heating, heat pumps, etc. According to the current emission factors, the carbon dioxide emissions of various building heat sources are calculated. The heat pump heating system emits the least carbon dioxide for every 1GJ of heat supplied among various heating energy systems; at the same time, as a renewable energy utilization device, the heat pump is the most effective way to heat with electricity. Its significant energy-saving and carbon-reduction characteristics have become one of the optimal technical solutions for replacing fossil energy and low-temperature heat production. This also shows that heat pump technology is the most effective way to achieve carbon neutrality. Therefore, heat pump technology has huge advantages in energy saving and emission reduction, and the application of building heat pump technology will bring huge emission reductions to the construction industry.

[0004] Having suitable renewable energy utilization equipment as a cold and heat source does not mean that energy conservation and emission reduction in the field of air conditioning and heating can be easily achieved. High-efficiency equipment is important, but the efficient operation of the entire system is the real key. However, the reality is often unsatisfactory, and even the unreasonable situation of energy efficiency ratio lower than 2.0 occurs. Therefore, when using an air source heat pump system to provide a building with a cold and heat source for air conditioning and heating, an efficient system method must be used to serve the station building construction, reduce the system operation energy consumption, make the system operate in a coordinated manner, and give full play to the high performance advantages of each device, thereby reducing carbon emissions during the operation of the building. Summary of the invention

[0005] In view of the problem of high system energy consumption when an air source heat pump system is used to provide cold and hot sources in the prior art, the present invention provides a high-efficiency air source heat pump station system.

[0006] The present invention is achieved through the following technical solutions:

[0007] A high-efficiency air source heat pump station system, including an intelligent control system, an air source heat pump system, a circulating pump unit, a constant pressure water supply vacuum degassing unit, a decontamination system, a soft water system, and pipelines, valves and related monitoring equipment connecting various units;

[0008] The intelligent control system is used to control the opening and closing of the air source heat pump system, the circulating pump group, the constant pressure water supply vacuum degassing unit, the decontamination system and the pipeline valves. The intelligent control system operates in a variable water temperature mode and a variable flow mode according to the terminal load conditions;

[0009] The air source heat pump system uses multiple independently controlled variable frequency and variable flow heat pump units, which are connected in parallel. Each unit is connected to the soft water system through its own branch pipes and valves. The intelligent control system controls the water temperature regulation of the air source heat pump system with a constant supply and return water temperature difference as the goal.

[0010] The circulating pump group adopts an integrated variable frequency pump group with multiple specifications connected in parallel and equipped with a control cabinet. The variable frequency pump group is matched by starting different water pumps or water pump frequency conversion according to the principle of "optimal efficiency optimization" by the intelligent control system;

[0011] The constant pressure water supply vacuum degassing unit is connected to the return water pipe on the suction side of the circulation pump unit, and the soft water system is connected to the water inlet side pipeline of the constant pressure water supply vacuum degassing unit;

[0012] The decontamination system is set in the main return water pipeline, and the air source heat pump system is connected to the circulation pump group;

[0013] Valves and related monitoring equipment are all installed on the pipeline and controlled by an intelligent control system.

[0014] Preferably, the air source heat pump system adopts a coupled high-efficiency air source heat pump.

[0015] Preferably, for the air source heat pump system, a variable frequency and variable flow air source heat pump unit with higher COP and IPLV values ​​is selected under the same cooling capacity, that is, in the extremely cold and cold zone A, a low temperature or ultra-low temperature heat pump unit is selected; when the project is large in scale, the cooling and heating loads are high, or the outdoor site is limited, an air-cooled screw heat pump unit is used.

[0016] Preferably, the heat pump unit is arranged outside the building, and there is no shielding around and on the top of the unit; the air source heat pump unit includes a top outlet unit and a side outlet unit according to the air outlet side. When multiple units are arranged side by side in parallel, the distance between two adjacent top outlet units in the horizontal direction is not less than 1.5m, in the vertical direction is not less than 2m, and the distance between them and the top shielding is not less than 3m;

[0017] When opening, the unit is opened row by row from the outside to the inside, and is opened from the outermost edges in two opposite directions, and then opened layer by layer from the outside to the inside; when closing, the unit is closed layer by layer from the middle to the outside, and is closed layer by layer from the middle to the opposite sides.

[0018] Preferably, multiple heat pump units are zoned and controlled according to the terminal load, and the number of zones is at least 3, and at least 3 heat pump units are arranged in each zone; the zones are arranged in parallel, and each zone is individually controlled by an intelligent control system through an independent electric control valve; the heat pump units and electric control valves in each zone are interlocked with the circulation pump group.

[0019] Preferably, a defrost detection module is configured on the heat pump unit, and the output end of the defrost detection module is connected to the input end of the intelligent control system; at the initial stage of frosting, the heat pump units in each partition are adjusted from the power frequency state to the low frequency state according to the partition; when the unit defrosts naturally, the heat pump units in the partition are turned off;

[0020] The defrost detection module includes a humidity acquisition module, a temperature acquisition module and a heat exchanger wind resistance acquisition module. The intelligent control system performs defrosting according to the predicted frost amount control logic and the self-learning defrost control logic;

[0021] When the outdoor weather deteriorates further in winter and the unit is frosted, the intelligent control system adopts a multi-mode coupled defrost method for defrosting. After zoning, it defrosts with a zone rotation defrost operation strategy. Each heat pump unit uses a double-circuit alternating hot gas bypass defrost technology for defrosting.

[0022] Preferably, the heat pump unit uses compact fins with a hydrophobic coating and adjustable angles.

[0023] Preferably, the air source heat pump system uses a heat pump unit with an energy storage unit, and the energy storage unit is opened and closed on the principle of "lowest cost" under the regulation of the intelligent control system.

[0024] Preferably, it also includes a water temperature monitoring system connected to the intelligent control system. The water temperature monitoring system transmits the change signal of the terminal load to the intelligent control system. The intelligent control system adjusts the water supply temperature of the air source heat pump system while keeping the water temperature difference unchanged.

[0025] Preferably, the diameter of the pipeline is set based on the fact that the pipeline specific friction resistance does not exceed 160Pa / m during cooling and does not exceed 80Pa / m during heating. The valve components use low-resistance basket filters, right-angle filters or diversion filters instead of Y-type filters, low-resistance silent check valves are used instead of disc check valves, low-resistance integrated multifunctional valves are used on vertical water pumps, low-resistance electromagnetic or ultrasonic heat meters are used instead of mechanical heat meters, and the resistance of the valve components is less than or equal to 3kPa.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention provides a high-efficiency air source heat pump station system through system intelligent control. The high-performance air source heat pump unit produces cold and heat in batches in different areas. The heat is supplied to the air conditioning or heating terminal by an integrated high-efficiency circulation pump unit through the low-resistance pipelines and valves of the system. To ensure the long-term stable and reliable operation of the system, after the cold and hot water are used at the terminal, they pass through the decontamination system and the constant-pressure water replenishment vacuum degassing unit before returning to the unit, completing the overall circulation of the high-efficiency air source heat pump station system.

[0028] Among them, the air source heat pump unit adopts variable frequency and variable flow type heat pump unit, the system can operate in energy-saving mode with variable water volume, and selects units with higher COP value and IPLV value under the same cooling capacity, which can solve the problem of efficient operation under variable working conditions; at the same time, the unit requires the use of refrigerant air replenishment technology that can not only improve the heating performance in low temperature environment but also take into account the efficient operation of high temperature heating and cooling conditions, which can realize the efficient operation of the unit in a wider range of different climate zones such as northern my country and the Yangtze River Basin. The selected integrated intelligent variable frequency pump unit operates efficiently and reduces the energy consumption of the transmission and distribution system, which can reduce the proportion of transmission and distribution energy consumption in the total energy consumption of the air source heat pump station system to less than 20%, and the system is more reasonable and more efficient. In the control process, it is difficult to achieve timely and accurate control because the time constant of the return water temperature feedback is too large, and the air source heat pump is more sensitive to the supply water temperature. Therefore, this method adopts the control logic of controlling the change of supply water temperature and constant supply and return water temperature difference to achieve refined control.

[0029] Furthermore, in the severe cold and cold A zone, low-temperature or ultra-low-temperature heat pump units are preferred, and gas-liquid mixed injection enthalpy increase technology (Enhanced Vapor Injection, EVI for short) is adopted. By introducing additional steam injection ports in the compressor, gas-liquid mixed injection is realized, thereby improving the performance of the system and greatly improving the low-temperature heating capacity, so that the unit can operate uninterruptedly at -25℃ outdoors and ensure that the outlet water is above 40℃. The single-unit air-cooled screw has more advantages in COP performance and larger capacity. When there are too many air-cooled scroll units used in the project, air-cooled screw units can be used to "slim down" the system, simplify control, and save floor space.

[0030] Furthermore, heat pump units with energy storage units are selected. This type of unit can be operated during the off-peak electricity price period at night and store the heat and cold produced by the system at a certain economic ratio; when the peak electricity price is reached during the day, the energy storage unit is used first to release the heat and cold supply project and the air source heat pump unit is shut down. This system saves operating costs while reducing the carbon emissions of the air source heat pump unit. The daytime operation is more stable, efficient and easier to control.

[0031] Furthermore, the arrangement of heat pump units in the air source heat pump system is limited in order to minimize the cold / heat island effect. The air source heat pump units arranged side by side in parallel are turned on row by row and partition by partition from the outermost row to the inside in winter and summer; and are turned off row by row and partition by partition from the middle row to the outside in winter and summer to improve the "cold / heat island" effect caused by a large number of units being placed together.

[0032] Furthermore, through a series of innovative means such as system zoning, the setting of electric valves supporting zoning, and interlocking with heat pump units and water pumps, not only energy-saving and carbon-reducing operation is achieved, the system can be finely adjusted by zoning to avoid inefficient operation when all outdoor units are turned on, but also the hot and cold output of the station system is matched with the indoor terminal demand, reducing the unscientific and frequent start and stop of the air source heat pump unit; at the same time, the setting of the zoning electric valve avoids the flow of hot water through the shut-down heat pump unit in winter, saving a lot of heat loss caused by the invalid bypass flow through the unit, which can reach 20% to 35% of the total heating capacity of the system. Through the above measures, the operating energy consumption of the entire building during air conditioning in summer and heating in winter can be reduced, making the system more efficient and helping to reduce carbon emissions during building operation.

[0033] Furthermore, frost is prone to form in winter when the outdoor air dry bulb temperature is greater than -12°C and less than 5.8°C, and the relative humidity is greater than 67%. The frost problem is a problem that all air source heat pump units will face under certain circumstances, which will lead to a reduction in the heating efficiency of the unit. The present invention adopts the technical concept of "frost suppression first, defrosting later". When defrosting is required, the units in the partition are all adjusted from the industrial frequency state to the low-frequency operation state, greatly reducing the probability of frost. When the outdoor environment further deteriorates, the units are shut down for natural defrosting according to the grouping, and the operation of the units in this area is shut down, relying on the units in other areas for heating.

[0034] Furthermore, the circulating pump group automatically and smoothly switches between large, medium and small pumps with different flow rates according to the changes in the flow rate in the system. Each pump is operated with variable frequency, so that when the flow rate of the entire system changes, the circulating pump group can always operate in the high-efficiency zone, reducing the system's transmission energy consumption. According to the change in the terminal load, the water flow in the system changes, so the circulating pump group starts different water pumps or matches the water pump frequency conversion according to the principle of "optimal efficiency optimization" to achieve the highest efficiency. Therefore, the circulating pump group does not correspond to the units in each partition, that is, there is a circulating pump group for each partition. The system can automatically reset the system water temperature according to the changes in the energy terminal load. While keeping the water temperature difference unchanged, the water supply temperature can be increased or decreased in a timely manner to realize variable water temperature control technology, achieve accurate adaptation of equipment performance and building load, improve system operation energy efficiency, and reduce host power consumption.

[0035] The startup sequence of the heat pump unit is: start the circulation pump group → open the electric valve on the partition pipeline → start the heat pump unit. The shutdown sequence is the opposite of the startup sequence. The on / off of related equipment must be confirmed before the next equipment can be turned on / off. If a fault occurs, the pump will stop automatically.

[0036] Furthermore, the constant-pressure water-makeup vacuum degassing unit can automatically read system information and utilize its own adjustment capability. When the water-makeup amount is reduced or no water is needed, the water-makeup pump can be kept off for a long time to achieve energy-saving operation. The equipment has a compact structure and occupies a small area, saving land resources. The equipment operates fully automatically, does not require special personnel to manage, and operates reliably. The degassing efficiency and deoxygenation efficiency are both greater than 99%, reducing cavitation and aerobic corrosion, and ensuring stable operation of the system.

[0037] Furthermore, a control logic of controlling the change of supply water temperature and maintaining a constant supply and return water temperature difference is adopted to achieve refined control. This is because the time constant of return water temperature feedback is too large during the control process, making it difficult to achieve timely and accurate control, and the air source heat pump is more sensitive to supply water temperature.

[0038] Furthermore, enlarging the pipe diameter helps to reduce the system's specific friction resistance. While reducing the resistance of the pipeline network, the head of the selected circulation pump group can be reduced, and the operating power of the circulation pump group will also be reduced accordingly; based on the measurement of the system pressure difference and flow, automatic optimization of pump operation is adopted to ensure that the started pump meets the system flow requirements and is always the most efficient choice. The pump group can operate within a wide flow range of 20 to 120%, and can cope with variable system flow and operating conditions. The efficiency meets the energy-saving evaluation value specified in "Energy Efficiency Limits and Energy-Saving Evaluation Values ​​of Clean Water Centrifugal Pumps" GB19762. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is an operation flow chart of a high-efficiency air source heat pump station system of the present invention;

[0040] Figure 2 This is an operation flow chart of a high-efficiency air source heat pump station system including an energy storage unit of the present invention;

[0041] Figure 3 It is a schematic diagram of the spacing arrangement of the top-outlet heat pump unit;

[0042] Figure 4 It is a schematic diagram of the spacing arrangement of the side-outlet heat pump unit;

[0043] Figure 5 This is a schematic diagram of the wind and snow protection treatment of the heat pump unit;

[0044] Figure 6 This is a schematic diagram of the relationship between the installation of heat pump units and the monsoon;

[0045] Figure 7It is a schematic diagram of water vapor nucleation in the frost suppression principle of the hydrophobic fins of the heat pump unit;

[0046] Figure 8 It is a schematic diagram of reducing condensed droplets in the frost suppression principle of the hydrophobic fins of the heat pump unit;

[0047] Fig. 9 It is a schematic diagram of the process of weakening heat conduction in the frost suppression principle of the hydrophobic fins of the heat pump unit;

[0048] Fig.10 This is the principle diagram of the alternating hot gas bypass defrosting technology;

[0049] Fig.11 Schematic diagram of the on / off strategy of the heat pump unit.

[0050] In the figure, 1. air source heat pump system; 2. circulation pump group; 3. decontamination system; 4. constant pressure water supply vacuum degassing unit; 5. soft water system; 6. soft water tank; 7. zoned electric butterfly valve; 8. low resistance valve; 9. ultrasonic heat meter; 10. flow sensor; 11. pressure sensor; 12. temperature sensor; 13. electric pressure differential bypass valve; 14. water supply pipeline; 15. return pipeline; 16. energy storage unit; 17. solenoid valve; 18. constant pressure tank; 19. first manual valve; 20. second manual valve; 21. third manual valve; 22. fourth manual valve; 23. intelligent control system. DETAILED DESCRIPTION

[0051] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0052] The present invention discloses a high-efficiency air source heat pump station system, referring to Figure 1 , 2, including an intelligent control system 23, an air source heat pump system 1, a circulating pump unit 2, a constant pressure water supply vacuum degassing unit 4, a decontamination system 3, a soft water system 5, and pipelines and valves 8 connecting the various units. Among them, the air source heat pump system 1 needs to be placed in a place with good ventilation and air exchange with the outdoors. It is the source of air conditioning and cooling in summer and heating in winter. The circulating water pump is an integrated pump group with its own control cabinet. It is a power equipment for transporting heat and cold for air conditioning and heating. The pipeline of the constant pressure water replenishment vacuum degassing unit 4 is connected to the return water main on the suction side of the circulating water pump, which plays the role of pressure stabilization, automatic water replenishment, automatic expansion and drainage, and removal of free gas and dissolved gas in the system. The decontamination system 3 is installed on the system return water main, which solves the problems of system corrosion, scaling, algae and water quality. The soft water system 5 prepares water suitable for the constant pressure water replenishment vacuum degassing unit 4, solves the water quality parameter index control and the user's special water quality requirements. The intelligent control system 23 is used to collect operation data and formulate the optimal operation strategy. It is the key to fully automated energy-saving operation and ensuring the safe and stable operation of the system. The water supply pipe 14 and the return pipe 15 are the necessary components for the organic connection between various equipment in the air source heat pump station, and are the medium for the transmission of heat and cold by the intelligent control system 23. The specific selection and configuration of each unit will be explained one by one later.

[0053] The intelligent control system 23 is used to control the opening and closing of the air source heat pump system 1, the circulation pump unit 2, the constant pressure water supply vacuum degassing unit 4, the decontamination system 3 and related valves (such as low resistance valves 8, partition electric butterfly valves 7, etc.), and the intelligent control system 23 operates the variable water temperature mode and the variable flow mode according to the terminal load conditions. In this embodiment, the intelligent control system 23 is installed in the control cabinet and is equipped with an expansion cabinet. By matching the main control cabinet and the expansion cabinet, the number of heat pump units can be greatly increased; at the same time, the intelligent control system 23 can realize the refined control and switching control of partition and group control, the full load increase and decrease start and stop of each unit in each partition, and the same frequency and low frequency operation of the units in each partition, so as to achieve the unmanned operation goal. When the number of heat pump units is too large, the expansion cabinet can be used to expand the number of heat pump units that are controlled. The intelligent control system 23 has intelligent operation and maintenance functions, fully automatic operation and perfect fault protection mechanism, which can realize different matching combinations of fixed / variable frequency air source heat pump units and fixed / variable frequency pump units, giving priority to the operation of high-efficiency equipment; real-time monitoring of the overall energy consumption of the system, and judging whether the entire heat pump station system should give priority to the use of variable water temperature control technology or variable flow control technology during operation according to the energy efficiency, and the intelligent control system 23 can be remotely monitored by a computer or a mobile phone.

[0054] The air source heat pump system 1 uses multiple independently controlled variable frequency and variable flow heat pump units, which are connected in parallel. Each unit is connected to the soft water system 5 through its own branch pipeline and partition electric butterfly valve 7; the intelligent control system 23 controls the water temperature regulation of the air source heat pump system with a constant supply / return water temperature difference as the goal.

[0055] For air source heat pump systems, variable frequency and variable flow air source heat pump units with higher COP and IPLV values ​​are selected under the same cooling capacity, and the system can operate with variable water volume and energy saving. Specifically: in severe cold and cold A areas, low temperature or ultra-low temperature heat pump units are selected. The units use gas-liquid mixed injection enthalpy increase technology, which can greatly improve the low temperature heating capacity. The units can operate uninterruptedly at -25℃ outdoors and ensure that the outlet water is above 40℃. When the project is large in size, the cold and hot loads are high, or the outdoor site is limited, air-cooled screw heat pump units are used instead of air-cooled scroll module heat pump units to achieve a "slimming" system, simplify control, and save floor space.

[0056] Reference Figure 3 , 4 , 5, 6. The heat pump unit is installed outside the building, and there are no obstructions around and on the top of the unit; the heat pump unit includes top-outlet units and side-outlet units according to the air outlet side. When multiple heat pump units are arranged side by side in parallel, the horizontal distance between two adjacent top-outlet units shall not be less than 1.5m, the vertical distance shall not be less than 2m, and the distance between them and the top obstructions shall not be less than 3m; in winter and summer, the units are opened row by row from the outside to the inside, and opened from the outermost sides in two opposite directions, and then opened layer by layer from the outside to the inside; when closing, the units are closed layer by layer from the middle to the outside, and closed layer by layer from the middle to the opposite sides.

[0057] Multiple heat pump units are controlled by zones according to the terminal load, and the number of zones is at least 3, and at least 3 heat pump units are set in each zone; each zone is set in parallel, and each zone is individually controlled by the intelligent control system 23 through an independent electric control valve 7; the heat pump units and electric control valves 7 in each zone are interlocked with the circulation pump group 2. In other words, the air source heat pump system 1 is adjusted by zones and controlled by groups, and the operating number and load of the heat pump units are flexibly adjusted according to actual needs, thereby reducing energy consumption and improving system energy efficiency. For example, the principles of increasing and decreasing the start and stop of the units in each zone and operating at the same frequency are as follows:

[0058] (1) The heat pump unit addition and subtraction control method is based on the compressor operating current RLA%.

[0059] Adding a heat pump unit: If the percentage of the unit's operating current to the rated current is greater than 95% of the set value, and this state lasts for 10 to 15 minutes, after determining the safety conditions, start another unit.

[0060] Heat pump unit reduction: When the percentage of the operating current of each unit to the rated current is less than 45% of the set value, one unit will be shut down after the safety condition is determined.

[0061] (2) When loading, use the "soft start" mode. First, reduce the operating conditions of the running units, and then start the next unit. Finally, increase the operating conditions of multiple units at the same time. When reducing the load, use the "soft shutdown" mode. First, reduce the operating conditions of multiple units, and then stop the operation of one unit. Through "soft start" and "soft shutdown", the huge impact of the unit on the power grid when starting and stopping can be avoided, ensuring the safety of the unit and the distribution station.

[0062] Reference Figure 7 , 8 , 9, 10, because it is easy to frost in winter when the outdoor air dry bulb temperature is greater than -12°C and less than 5.8°C, and the relative humidity is greater than 67%. The frost problem is a problem that all air source heat pump systems 1 will face under certain circumstances, which will lead to a decrease in the heating efficiency of the unit. Therefore, in the present invention, a defrost detection module is configured on the heat pump unit, and the output end of the defrost detection module is connected to the input end of the intelligent control system 23; at the initial stage of frosting, the heat pump unit is adjusted from the industrial frequency state to the low frequency state according to the partition; when the heat pump unit undergoes natural defrosting, the heat pump unit in the partition is turned off.

[0063] During the winter defrosting process, about 63% of the defrosting processes will be mistaken, which will cause large fluctuations in the operating conditions of the unit and even affect its safety. Therefore, the defrosting detection module in the present invention includes a humidity acquisition module, a temperature acquisition module and a heat exchanger wind resistance acquisition module. The intelligent control system 23 performs defrosting according to the predicted frost amount control logic and the self-learning defrosting control logic. The multi-variable acquisition detection increases the judgment basis for defrosting and helps to achieve accurate defrosting; adding the self-learning defrosting control logic reduces the probability of mistaken defrosting. Among them, the heat exchanger wind resistance is an important indicator to measure the thickness of the frost layer and its impact on the performance of the equipment. As the frost layer thickens, the air circulation is blocked, the wind resistance increases, and the heat exchange effect is directly affected. The heat exchanger wind resistance acquisition module can intuitively reflect the accumulation of the frost layer by monitoring the change of wind resistance, providing a direct basis for the system to start the defrosting program in time.

[0064] The predicted frost control logic is based on multivariate data such as humidity, temperature and wind resistance. It uses algorithms to predict the frost amount, plans the defrosting plan in advance, ensures that defrosting is started at the best time, and reduces energy consumption losses. The process is as follows: The predicted frost control logic refers to collecting relevant data through temperature, humidity, wind resistance change detection and acquisition modules, and then constructing a regional frost map, and normalizing the frost rate and frost time of each frost zone in the map. Then, the frost zone entered during the operation of the air conditioner is determined according to the real-time air dry bulb temperature and relative humidity. Finally, the frost amount in each frost zone during the operation of the air conditioner is calculated according to the frost zone entered during the operation of the air conditioner, and the frost rate and frost time of the frost zone after normalization. The frost amount of the air conditioner is predicted by normalizing the frost amount in each frost zone. The self-learning defrost control logic is based on the predicted frost control logic. It memorizes, stores and compares the frost status during the actual operation of the air conditioner in winter each year, continuously enriches and improves the relevant database, and reacts to the predicted frost control system to make the logic control of the next year more accurate and practical.

[0065] When the outdoor weather deteriorates further in winter and the unit is frosted, the intelligent control system 23 uses a multi-mode coupled defrosting method for defrosting. After partitioning, defrosting is performed using a partition rotation defrosting operation strategy. Each heat pump unit uses a double-circuit alternating hot gas bypass defrosting technology for defrosting. Among them, the rotation defrosting operation control strategy can achieve natural defrosting of the system, and the double-circuit alternating hot gas bypass defrosting technology can achieve uninterrupted heating and defrosting, without affecting the indoor heating demand, improving indoor comfort and system stability. For example, in the winter when the outdoor environment gradually becomes worse and gradually enters the stage of frosting, priority is given to zoning the system so that all units in the partition are adjusted from the power frequency state to the low-frequency operation state, which can greatly reduce the probability of frosting.

[0066] The heat pump unit uses compact fins with hydrophobic coating and adjustable angles. The hydrophobic coating can inhibit the nucleation of water vapor on the fin surface, reduce the distribution density of condensed droplets, weaken the heat conduction process, and inhibit the formation of frost. The compact fins with adjustable angles are selected to avoid secondary frost after defrosting. The air in the closed space formed by the nanostructure on the fin surface and the frost layer expands due to heat, and the adhesion of the solid surface weakens. At this time, the frost layer on the fin can be directly peeled off, and the amount of water retained on the surface will be greatly reduced. In this embodiment, the coating is obtained by solution etching, deionized water boiling and fluorination with fluorosilane vapor; the fin substrate is made of aluminum alloy.

[0067] Reference Figure 2, the air source heat pump system uses a coupled high-efficiency air source heat pump group with an energy storage unit 16, and the air source heat pump system 1 is opened and closed according to the principle of "minimum cost" under the control of the intelligent control system 23. Common energy storage types include ice energy storage systems, water energy storage systems, phase change material energy storage systems and other energy storage systems. Energy storage devices have broad application prospects in the fields of refrigeration and heating, which can effectively reduce operating costs, improve energy utilization efficiency, and play a positive role in the peak-valley balance of the power grid. When selecting the energy storage unit 16, it is necessary to comprehensively consider multiple factors such as specific application scenarios, technical economy, and environmental protection. In this embodiment, according to the electricity consumption policies of different regions, when the peak-valley electricity price ratio exceeds 3:1, a coupled high-efficiency air source heat pump system is preferred. At peak electricity prices, the energy storage unit 16 is used as the cold and heat source of the air-conditioning system, and only the circulating pump group 2 is operated during the peak load period during the day. It is easier to operate and regulate in intelligent control, consumes less energy, and the system is more stable and reliable, while the operating cost is greatly reduced.

[0068] In this embodiment, a constant pressure tank 18 and a solenoid valve 17 are provided on the return water pipe 15 of the circulation pump group 2. The constant pressure tank 18 can buffer the water pressure fluctuation in the system and ensure the stability of the system water pressure, which is very important for protecting the system equipment and improving the system operation efficiency. The solenoid valve 17, as a control valve on the return water pipe 15, can accurately control the flow rate of the return water according to the system requirements. By connecting to the intelligent control system 23, the solenoid valve 17 can realize automatic control.

[0069] The circulation pump group 2 adopts an integrated variable frequency pump group with multiple specifications in parallel and a built-in control cabinet. The efficient operation of the integrated intelligent variable frequency pump group can reduce the energy consumption of the transmission and distribution system, so that the proportion of the transmission and distribution energy consumption in the total energy consumption of the high-efficiency air source heat pump station system is reduced to less than 20%, and the system is more reasonable and more efficient. The circulation pump group 2 is based on the change of the terminal load, and the water flow in the system changes. At this time, the circulation pump group 2 starts different water pumps or water pump frequency conversion for matching according to the principle of "optimal efficiency optimization" under the control of the intelligent control system 23 to achieve the highest efficiency. For example, according to the measurement of the system pressure difference and flow, the automatic optimization pump operation is adopted, so that the pump started meets the system flow requirements and is always the optimal efficiency choice. The pump group can operate in a wide flow range of 20-120%, and can cope with the system variable flow and variable working conditions. The efficiency meets the energy-saving evaluation value specified in GB19762 "Energy Efficiency Limit Value and Energy-Saving Evaluation Value of Clean Water Centrifugal Pump".

[0070] The circulation pump group 2 has its own control cabinet and can open a protocol with the computer room group control system. According to the changes in the flow rate in the system, the intelligent control system 23 automatically and smoothly switches large, medium and small pumps with different flow rates. Each pump is operated with variable frequency, so that when the flow rate of the entire station system changes, the circulation pump group 2 can always operate in the high-efficiency area accordingly, reducing the system's transportation energy consumption.

[0071] The startup sequence of the air source heat pump unit 1 in an air source heat pump station system of the present invention is: start the circulation pump group 2 → open the electric valve on the partition pipeline → start the heat pump unit, and the shutdown sequence is the opposite of the startup sequence. The on / off of the relevant equipment needs to be confirmed before the next equipment can be turned on / off. In the event of a fault, the pump will stop automatically. In the present embodiment, a flow meter is provided in the circulation pump group 2, and the flow meter feeds back the real-time flow of the system. When passing through the same flow-head operating point, different numbers and frequencies of large, medium and small pumps will be combined according to the different flow rates. Combined with the system flow-efficiency curve, the system can select the best matching solution so that the system always runs at the highest efficiency point in this stage.

[0072] When the load required by the end becomes smaller, the pressure difference between the cold and hot water mains changes, the cold water demand at the end becomes smaller, and the electric pressure difference bypass valve 13 is opened by regulation, and the excess water supply is transferred to the return water main through the electric pressure difference bypass pipe, and the end flow rate changes. At this time, the water pump is frequency-controlled, and the load side is variable flow operation; when the load side demand becomes smaller, the flow rate can also be kept constant, that is, after the pressure difference changes, the temperature sensor 12 on the supply and return water mains can be used for comparison, and the system feeds back to the heat pump unit, so that the heat pump unit raises or lowers the water supply temperature, thereby keeping the supply and return water temperature difference unchanged, such as the return water temperature increases by the same temperature, and the COP value of the unit increases by at least 3% to 5% for every 1°C increase in the water supply temperature, and the operation is more energy-efficient. Therefore, the system provided by the present invention has two adjustment modes of variable water temperature and variable water volume, and can be adjusted manually or compared by an automatic control algorithm. The results are compared under the premise of energy saving, so as to select the optimal mode.

[0073] The constant pressure water supply vacuum degassing unit 4 is connected to the return water pipe on the suction side of the circulation pump unit 2. The constant pressure water supply vacuum degassing unit 4 can automatically read the system information and use its own adjustment ability. When the water consumption is reduced or no water is used, the water supply pump can be kept off for a long time to achieve energy-saving operation. The equipment has a compact structure and occupies a small area, saving land resources. The equipment runs fully automatically, does not require special management, and runs reliably. The degassing efficiency and deoxygenation efficiency are both greater than 99%, reducing cavitation and aerobic corrosion, so that the system can run stably.

[0074] When the water system is circulating, on the one hand, there is a large amount of gas. If it is not removed, it is easy to cause gas blockage, resulting in poor circulation and uneven heating and cooling of the local or entire system, as well as damage to equipment and pipelines; on the other hand, the oxygen contained in the water causes corrosion, perforation, and water leakage of terminal equipment such as heating (refrigeration) equipment, pipelines or steel radiators, which will directly affect the safety of the entire system. The degassing equipment in the unit generates a vacuum through the equipment without changing the water temperature according to Henry's law (a certain amount of gas is dissolved in water at a certain temperature and pressure, and when the temperature increases or the pressure decreases, the dissolved gas in the water will decrease). The free gas and dissolved gas in the water are released and then discharged from the system through the automatic exhaust valve. The degassed unsaturated water will absorb the gas in the system to seek gas-water balance. In this way, all gases in the system water are removed to ensure stable and safe operation of the system.

[0075] The soft water system 5 is connected to the water inlet side pipeline of the constant pressure water replenishment vacuum degassing unit 4; the decontamination system 3 is arranged in the total return water pipeline, and the air source heat pump system 1 is connected to the circulation pump group 2. In this embodiment, the inlet water of the soft water system 5 is municipal tap water. After the tap water enters the soft water system for softening treatment, the outlet water enters the softening water tank 6. The decontamination system 3 can continuously process the full flow of the system water quality during operation and filter body regeneration without affecting the normal operation of the system; it can realize high-precision filtration-drainage-filtration continuous operation; the radio frequency physical field processing technology is adopted to enhance the processing efficiency and solve the problem of mutual interference and reduced efficiency between different spectrums; the PLC programmable control technology is adopted to realize linkage, switching and full automatic operation of the whole equipment; through the online dynamic monitoring system, the water quality is continuously monitored in real time to guide the operation of the equipment.

[0076] It also includes a water temperature monitoring system connected to the intelligent control system 23. The water temperature monitoring system will transmit the change signal of the terminal load to the intelligent control system 23. The intelligent control system 23 adjusts the water supply temperature of the air source heat pump system 1 while keeping the water temperature difference unchanged, so as to timely increase or decrease the water supply temperature, realize variable water temperature control technology, achieve accurate adaptation of equipment performance and building load, improve system operation energy efficiency, and reduce host power consumption.

[0077] The low resistance valve 8 is arranged on the pipeline and is controlled by the intelligent control system 23. The diameter of the pipeline is set according to the specific friction resistance. In this embodiment, the specific friction resistance of the pipeline of the whole system during cooling does not exceed 160Pa / m, preferably 150Pa / m; the specific friction resistance of the pipeline during heating does not exceed 80Pa / m, preferably 75Pa / m.

[0078] The low-resistance valve component 8 adopts a low-resistance basket filter, a right-angle filter or a guide filter instead of a Y-type filter, adopts a low-resistance silent check valve instead of a disc check valve, adopts a low-resistance integrated multifunctional valve on the vertical water pump, and adopts a low-resistance electromagnetic or ultrasonic heat meter 9 instead of a mechanical heat meter. The resistance of the low-resistance valve component 8 is less than or equal to 3kPa. In this embodiment, the air source heat pump system 1, the circulation pump group 2, the soft water system 5, the constant pressure water replenishment vacuum degassing unit 4, and the decontamination system 3 form a circulation system through the water supply pipe 14 and the return pipe 15. The ultrasonic heat meter 9, the first manual valve 19 and the third manual valve 21 are all arranged on the water supply pipe 14, and the second manual valve 20 and the fourth manual valve 22 are arranged on the return pipe 15. When storing energy, the first manual valve 19 and the second manual valve 20 are in the open state, and the third manual valve 21 and the fourth manual valve 22 are in the closed state; when directly supplying, the first manual valve 19 and the second manual valve 20 are in the closed state, and the third manual valve 21 and the fourth manual valve 22 are in the open state. An electric pressure difference bypass valve 13 is arranged in the pipeline of the decontamination system 3, and the bypass flow in the system pipeline is adjusted by controlling the opening of the valve, so as to keep the pressure difference at both ends of the supply and return water mains constant. When the system pressure difference increases and exceeds the set value of the control valve, the valve will automatically open wider to allow more water to flow through the bypass line, thereby reducing the system pressure difference; conversely, when the system pressure difference decreases, the valve will close accordingly to maintain the stability of the system pressure difference.

[0079] The startup strategy of a high-efficiency air source heat pump station system of the present invention refers to Fig.11 As shown, when the heat pump host is turned on in winter and summer, it is turned on layer by layer from the outside to the inside according to the gradual increase in load along the direction of arrow A, so as to reduce the "cold and hot island" effect; when the heat pump host is turned off in winter and summer, it is turned off layer by layer from the inside to the outside according to the gradual decrease in load along the direction of arrow B, so as to reduce the "cold and hot island" effect; when the unit enters winter operation, as the outdoor temperature gradually drops, in order to reduce the probability of frost, the operating frequency of the heat pump unit in the opened partition can be reduced first, and can be adjusted to operate at a medium or low frequency of 50% to 80%.

[0080] The high-efficiency air source heat pump station system of the present invention can operate with high efficiency and energy saving. According to the changes in the outdoor environment, the water supply temperature is changed accordingly to avoid excessive cooling or heating of the system, which not only causes waste but also affects the comfort of indoor personnel. For example, in early summer, the outdoor temperature is not very high. After the heat pump units are divided into zones, the units in some zones can be started according to the terminal load demand, and the water supply temperature can be increased to meet the terminal use requirements. At the same time, the COP of the heat pump units is improved accordingly; in midsummer, the heat pump units can start most or all of the units in the zones to reduce the water supply temperature to normal; the startup method in late summer can be the same as in early summer. The control mode in winter is opposite to that in summer.

[0081] The present invention provides a high-efficiency air source heat pump station system. Through a series of innovative means such as system zoning, the setting of electric valves supporting the zones, and interlocking with the heat pump unit and the water pump, not only does it achieve energy-saving and carbon-reducing operation, but also enables the system to perform fine operation adjustment according to the zones, avoiding the inefficient operation of all outdoor units being turned on, and makes the cold and hot output of the station system match the indoor terminal demand, reducing the unscientific and frequent start and stop of the air source heat pump system 1; at the same time, the setting of the zone electric valves avoids the flow of hot water through the shut-down heat pump unit in winter, saving a large amount of heat loss caused by invalid bypass flow through the unit. This part of heat loss can reach 20% to 35% of the total heating capacity of the system, which has a huge impact.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to impose any limitation on the technical solution of the present invention. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can also be subjected to several simple modifications and substitutions, and these modifications and substitutions are also within the scope of protection covered by the claims.

Claims

1. A high-efficiency air source heat pump station system, characterized in that: It includes intelligent control system, air source heat pump system, circulation pump unit, constant pressure water supply vacuum degassing unit, decontamination system, soft water system, and pipelines, valves and related monitoring equipment connecting each unit; The intelligent control system is used to control the opening and closing of the air source heat pump system, the circulating pump group, the constant pressure water supply vacuum degassing unit, the decontamination system and the pipeline valves. The intelligent control system operates in a variable water temperature mode and a variable flow mode according to the terminal load conditions; The air source heat pump system uses multiple independently controlled and parallel variable frequency and variable flow heat pump units. Each unit is connected to the soft water system through its own branch pipes and valves. The intelligent control system controls the water temperature regulation of the air source heat pump system with a constant supply and return water temperature difference as the goal. The circulating pump group adopts an integrated variable frequency pump group with multiple specifications connected in parallel and equipped with a control cabinet. The variable frequency pump group is matched by starting different water pumps or water pump frequency conversion according to the principle of "optimal efficiency optimization" by the intelligent control system; The constant pressure water supply vacuum degassing unit is connected to the return water pipe on the suction side of the circulation pump unit, and the soft water system is connected to the water inlet side pipeline of the constant pressure water supply vacuum degassing unit; The decontamination system is set in the main return water pipeline, and the air source heat pump system is connected to the circulation pump group; Valves and related monitoring equipment are all installed on the pipeline and controlled by an intelligent control system.

2. The high-efficiency air source heat pump station system according to claim 1 is characterized in that: The air source heat pump system adopts a coupled high-efficiency air source heat pump unit.

3. The high-efficiency air source heat pump station system according to claim 2 is characterized in that: For air source heat pump systems, variable frequency and variable flow air source heat pump units with higher COP and IPLV values ​​are selected under the same cooling capacity. That is, in extremely cold and cold zones A, low temperature or ultra-low temperature heat pump units are selected; when the project is large, the cooling and heating loads are high, or the outdoor site is limited, air-cooled screw heat pump units are used.

4. The high-efficiency air source heat pump station system according to claim 3 is characterized in that: The heat pump unit is installed outside the building, and there are no shielding around or on the top of the unit. The heat pump unit includes top-outlet units and side-outlet units according to the air outlet side. When multiple units are arranged side by side in parallel, the horizontal distance between two adjacent top-outlet units shall not be less than 1.5m, the vertical distance shall not be less than 2m, and the distance between the top shielding shall not be less than 3m; When opening, the unit is opened row by row from the outside to the inside, and is opened from the outermost edges in two opposite directions, and then opened layer by layer from the outside to the inside; when closing, the unit is closed layer by layer from the middle to the outside, and is closed layer by layer from the middle to the opposite sides.

5. The high-efficiency air source heat pump station system according to claim 4 is characterized in that: Multiple heat pump units are zoned and controlled according to the terminal load, and the number of zones is at least 3, with at least 3 heat pump units installed in each zone; the zones are connected in parallel, and each zone is individually controlled by an intelligent control system through an independent electric control valve; the heat pump units and electric control valves in each zone are interlocked with the circulation pump group.

6. The high-efficiency air source heat pump station system according to claim 5 is characterized in that: The heat pump unit is equipped with a defrost detection module, and the output end of the defrost detection module is connected to the input end of the intelligent control system; at the initial stage of frosting, the heat pump units in each zone are adjusted from the power frequency state to the low frequency state according to the zone; when the unit defrosts naturally, the heat pump unit in the zone is turned off; The defrost detection module includes a humidity acquisition module, a temperature acquisition module and a heat exchanger wind resistance acquisition module. The intelligent control system performs defrosting according to the predicted frost amount control logic and the self-learning defrost control logic; When the outdoor weather deteriorates further in winter and the unit is frosted, the intelligent control system adopts a multi-mode coupled defrost method for defrosting. After zoning, it defrosts with a zone rotation defrost operation strategy. Each heat pump unit uses double-circuit alternating hot gas bypass defrost technology for defrosting.

7. The high-efficiency air source heat pump station system according to claim 6 is characterized in that: The heat pump unit uses compact fins with hydrophobic coating and adjustable angle.

8. The high-efficiency air source heat pump station system according to claim 2 is characterized in that: The air source heat pump system uses a heat pump unit with an energy storage unit, and the energy storage unit is opened and closed based on the "lowest cost" principle under the control of the intelligent control system.

9. The high-efficiency air source heat pump station system according to claim 2, characterized in that: It also includes a water temperature monitoring system connected to the intelligent control system. The water temperature monitoring system transmits a terminal load change signal to the intelligent control system. The intelligent control system adjusts the water supply temperature of the air source heat pump system while keeping the water temperature difference unchanged.

10. The high-efficiency air source heat pump station system according to claim 1, characterized in that: The pipe diameter is set based on the fact that the specific friction resistance of the pipeline does not exceed 160Pa / m during cooling and does not exceed 80Pa / m during heating. The valve components use low-resistance basket filters, right-angle filters or diversion filters instead of Y-type filters, and low-resistance silent check valves instead of disc check valves. Low-resistance integrated multifunctional valves are used on vertical water pumps, and low-resistance electromagnetic or ultrasonic heat meters are used instead of mechanical heat meters. The resistance of valve components is less than or equal to 3kPa.

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