A frost-proof solar heat-supplementing double-energy-storage air conditioner fresh air pretreatment system in cold regions

Abstract

The application discloses a cold region anti-frosting solar heat supplementing double-energy-storage air conditioner fresh air pretreatment system, and belongs to the field of refrigeration heat pump air conditioning system design and manufacturing. The fresh air pretreatment system comprises a first heat accumulator, a second heat accumulator, an air handling unit, a solar auxiliary heat supplementing module and a heat supplementing control module. In winter, the first heat accumulator and the second heat accumulator alternately absorb indoor return air waste heat to store heat and preheat outdoor fresh air through heat release. The indoor return air and the preheated outdoor fresh air are transported to the air handling unit, and then are sent into the indoor through the air handling unit. The heat supplementing control module controls the solar auxiliary heat supplementing module to store heat in the first heat accumulator or the second heat accumulator according to the temperature before and after the preheating of the outdoor fresh air when the heat release of the first heat accumulator or the second heat accumulator is insufficient. The application solves the problem that the direct entry of low-temperature fresh air into a total heat exchanger in a cold region in winter easily leads to frost formation, and realizes continuous and stable preheating of air conditioner fresh air.

Description

Technical Field

[0001] This invention belongs to the field of refrigeration and heat pump air conditioning system design and manufacturing, specifically relating to a cold region anti-frost solar-heated dual-energy storage air conditioning fresh air pretreatment system. Background Technology

[0002] In cold regions during winter, the outdoor fresh air temperature is often far below freezing when the air conditioning system is running. If this low-temperature fresh air directly enters the heat exchanger of the heat pump system, frost formation is highly likely on the exchanger surface due to the large temperature difference and condensation of water vapor in the air. The formation of frost significantly increases heat exchange resistance and reduces the heat transfer coefficient. It also blocks airflow channels, increases flow resistance, and significantly increases energy consumption. Therefore, increasing the fresh air temperature in winter is crucial to suppressing frost formation on the heat exchanger and ensuring the efficient operation of the air conditioning system.

[0003] One feasible technical approach to increasing the temperature of fresh air in winter is to utilize waste heat from exhaust air to preheat the fresh air. Exhaust air heat recovery can recover heat from indoor exhaust air, thus raising the fresh air temperature to some extent. However, on the one hand, traditional exhaust air heat recovery systems often use a single heat storage device, which has significant drawbacks: the temperature of the heat storage body continuously decreases during operation, and the heat recovery efficiency significantly decreases over time, making it difficult to achieve continuous and stable preheating of fresh air. On the other hand, the waste heat from indoor exhaust air is insufficient to provide supplementary heat, requiring a new heat source for auxiliary heating to jointly raise the fresh air temperature above the frost risk temperature. Summary of the Invention

[0004] This invention provides a dual-energy storage air conditioning fresh air pretreatment system with solar-powered heating to prevent frost formation in cold regions, aiming to solve the problem of frost formation caused by low-temperature fresh air directly entering the total heat exchanger during winter. This invention achieves continuous and stable preheating of air conditioning fresh air through alternating operation of dual heat storage devices and solar-powered heating.

[0005] A cold-region anti-frost solar-powered dual-energy storage air conditioning fresh air pretreatment system includes a first heat storage unit, a second heat storage unit, an air handling unit, a solar-assisted heating module, and a heating control module. In winter, the first and second heat storage units alternately absorb residual heat from indoor return air for heat storage and preheat outdoor fresh air by releasing heat. The indoor return air and preheated outdoor fresh air are transported to the air handling unit, processed, and then sent indoors. The heating control module, based on the temperature of the outdoor fresh air before and after preheating, controls the solar-assisted heating module to store heat in either the first or second heat storage unit when the heat release from the first or second heat storage unit is insufficient.

[0006] Furthermore, the fresh air pretreatment system also includes an indoor return air circuit, a first outdoor fresh air circuit, and a second outdoor fresh air circuit; the indoor return air circuit has an inlet A, an outlet B, and an outlet C, with the inlet located indoors; the first outdoor fresh air circuit has an inlet A', an outlet B', and an outlet C', with inlet A' located outdoors; the second outdoor fresh air circuit has an inlet A”, an outlet B”, and an outlet C”, with inlet A” located outdoors; the air handling unit has a fresh air inlet and an indoor return air inlet; the first heat accumulator has four interconnected fluid ports, the four ports of the first heat accumulator respectively The first exhaust duct is connected to outlet B, outlet B', the inlet of the first exhaust duct, and the inlet of the first supply duct. The outlet of the first exhaust duct is located outdoors, and the outlet of the first supply duct is connected to the fresh air inlet of the air handling unit. Outlet C' is connected to the inlet of the first exhaust duct. The second heat accumulator has four interconnected fluid ports, and the four ports of the second heat accumulator are respectively connected to outlet C, outlet B', the inlet of the second exhaust duct, and the inlet of the second supply duct. The outlet of the second exhaust duct is located outdoors, and the outlet of the second supply duct is connected to the fresh air inlet of the air handling unit. Outlet C' is connected to the inlet of the second exhaust duct.

[0007] Furthermore, the outlets B, C, B', C', B”, C”, the inlet of the first exhaust duct, the inlet of the second exhaust duct, the inlet of the first supply duct, and the inlet of the second supply duct are all equipped with a first air valve, a fourth air valve, a ninth air valve, a tenth air valve, a seventh air valve, an eighth air valve, a second air valve, a sixth air valve, a third air valve, and a fifth air valve.

[0008] Furthermore, the indoor return air circuit is equipped with a first fan, the first outdoor fresh air circuit is equipped with a third fan, the second outdoor fresh air circuit is equipped with a second fan, and the fresh air inlet of the air handling unit is equipped with a fourth fan.

[0009] Furthermore, the solar-assisted heating module includes a solar collector, a first circulating pump, a hot water storage tank, and a second circulating pump; the working medium in the solar collector, the first circulating pump, and the hot water storage tank circulates through pipelines; the first and second accumulators are also equipped with heat storage body heating pipes; the working medium in the hot water storage tank heats the heat storage body in the first and second accumulators through the heat storage body heating pipes.

[0010] Furthermore, the output port of the hot water storage tank is connected to the input port of the heating pipe of the first and second accumulators via a second three-way valve; a second circulation pump is provided between the output port of the hot water storage tank and the second three-way valve; the input port of the hot water storage tank is connected to the output port of the heating pipe of the first and second accumulators via a first three-way valve.

[0011] Furthermore, the heat replenishment control module includes a first temperature controller, a second temperature controller, a first thermometer, a second thermometer, a third thermometer, and a fourth thermometer; the first thermometer is located at the outlet of the first air supply duct, and the second thermometer is located at the outlet of the second air supply duct; the third thermometer is located on the second outdoor fresh air circuit behind the second fan; the fourth thermometer is located on the first outdoor fresh air circuit behind the third fan; the input terminals of the first temperature controller are respectively connected to the second thermometer and the third thermometer, and the output terminals are respectively connected to the first three-way valve and the second three-way valve; the input terminals of the second temperature controller are respectively connected to the first thermometer and the fourth thermometer, and the output terminals are respectively connected to the first three-way valve and the second three-way valve.

[0012] Furthermore, the fresh air pretreatment system also includes a first cold storage unit and a second cold storage unit; in summer, the first cold storage unit and the second cold storage unit utilize the low temperature air at night to charge the air, and release the stored cold energy during the day to pre-cool the outdoor fresh air. The indoor return air and the pre-cooled outdoor fresh air are transported to the air handling unit, and after being processed by the air handling unit, they are sent into the room.

[0013] Furthermore, the fresh air pretreatment system also includes a first cold storage unit and a second cold storage unit; the first cold storage unit is provided with three interconnected fluid ports, and the first cold storage unit is connected between the first heat storage unit and the inlet of the first exhaust duct through two of its ports, and the other port of the first cold storage unit is connected to the outlet C'; the second cold storage unit is provided with three interconnected fluid ports, and the second cold storage unit is connected between the second heat storage unit and the inlet of the second exhaust duct through two of its ports, and the other port of the second cold storage unit is connected to the outlet C”.

[0014] Furthermore, the operating mode of the fresh air pretreatment system is as follows:

[0015] Operating mode 1: Winter heating operation, the first heat storage unit and the first heat storage unit alternately absorb the waste heat of indoor return air for heat storage and preheat the outdoor fresh air by releasing heat;

[0016] Operating mode 2: Winter heating operation. When the first heat storage device or the first heat storage device is insufficient, the solar auxiliary heating module automatically supplements the heat of the first heat storage device or the first heat storage device, based on operating mode 1.

[0017] Operating Mode 3: During summer nighttime cooling and cold storage, in the first stage, outdoor fresh air enters the second cold storage unit, releases its cooling capacity in the second cold storage unit, and is then discharged to the outside; outdoor fresh air and indoor return air are processed by the air handling unit and then sent into the room; in the second stage, a portion of the outdoor fresh air releases its cooling capacity in the first cold storage unit and is then discharged to the outside; the other portion of the outdoor fresh air and indoor return air are processed by the air handling unit and then sent into the room.

[0018] Operating Mode 4: During summer daytime cooling, in the first stage, outdoor fresh air enters the second cold storage unit, which releases cooling energy to the outdoor fresh air. Indoor return air and outdoor fresh air treated by the second cold storage unit enter the air handling unit for further processing before being sent indoors. In the second stage, outdoor fresh air enters the first cold storage unit, which releases cooling energy to the outdoor fresh air. Indoor return air and outdoor fresh air treated by the first cold storage unit enter the air handling unit for further processing before being sent indoors.

[0019] Beneficial effects:

[0020] (1) This invention can avoid the problem of frost formation in total heat exchangers. By combining indoor exhaust heat recovery with solar energy supplementation to increase the fresh air temperature, the fresh air inlet is always kept above the frost risk temperature, ensuring the efficient and stable operation of the air conditioning system in winter.

[0021] (2) The present invention can realize continuous and stable exhaust heat recovery. The two heat storage devices operate alternately in a periodic manner, with one storing heat while the other releases heat, which overcomes the defect of efficiency decay of a single heat storage device and realizes continuous and stable fresh air preheating.

[0022] (3) The present invention provides reliable heating under extreme conditions. The solar-assisted heating module automatically activates when the heat storage device is insufficient, solving the problem of the lack of backup heat source in traditional systems.

[0023] (4) This invention achieves dual energy storage in winter and summer by adding a cold storage device. In summer, the cold storage device is cooled by low-temperature air at night, and the cold energy is released during the day to pre-cool fresh air, thereby improving the annual utilization rate of the equipment and reducing the overall energy consumption of the system.

[0024] (5) Significantly improved energy efficiency throughout the year. Compared with traditional single thermal storage heat recovery systems, the overall energy efficiency ratio of this invention is expected to be improved by 20%-30% throughout the year. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the fresh air pretreatment system in Example 1;

[0026] Figure 2 This is a schematic diagram of the fresh air pretreatment system in Example 2. Detailed Implementation

[0027] The technical solution of the present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited to the embodiments described.

[0028] Example 1

[0029] like Figure 1As shown, the present invention provides a cold region anti-frost solar-powered dual-energy storage air conditioning fresh air pretreatment system, characterized in that the fresh air pretreatment system includes a first heat storage unit 4, a second heat storage unit 10, a first cold storage unit 5, a second cold storage unit 13, an indoor return air circuit, a first outdoor fresh air circuit, a second outdoor fresh air circuit, a first exhaust duct, a second exhaust duct, a first supply air duct, a second supply air duct, an air handling unit 26, a solar-assisted heating module, and a heating control module.

[0030] (i) The indoor return air circuit is provided with inlet A, outlet B and outlet C, with the inlet located indoors; the first outdoor fresh air circuit is provided with inlet A', outlet B' and outlet C', with inlet A' located outdoors; the second outdoor fresh air circuit is provided with inlet A”, outlet B” and outlet C”, with inlet A” located outdoors; the air handling unit 26 is provided with a fresh air inlet and an indoor return air inlet.

[0031] The outlets B, C, B', C', B”, C”, the inlet of the first exhaust duct, the inlet of the second exhaust duct, the inlet of the first supply duct, and the inlet of the second supply duct are respectively equipped with a first air valve 3, a fourth air valve 9, a ninth air valve 23, a tenth air valve 24, a seventh air valve 18, an eighth air valve 19, a second air valve 6, a sixth air valve 14, a third air valve 7, and a fifth air valve 11.

[0032] The indoor return air circuit is equipped with a first fan 2, the first outdoor fresh air circuit is equipped with a third fan 21, the second outdoor fresh air circuit is equipped with a second fan 16, and the fresh air inlet of the air handling unit 26 is equipped with a fourth fan 25. The indoor return air circuit is equipped with a first filter 1, located between inlet A and the first fan 2; the first outdoor fresh air circuit is equipped with a third filter 20, located between inlet A' and the third fan 21; and the second outdoor fresh air circuit is equipped with a second filter 15, located between inlet A'" and the second fan 16.

[0033] (ii) The first heat accumulator 4 is provided with four interconnected fluid ports. The four ports of the first heat accumulator 4 are respectively connected to outlet B, outlet B', the inlet of the first exhaust duct, and the inlet of the first supply duct. The outlet of the first exhaust duct is located outdoors, and the outlet of the first supply duct is connected to the fresh air inlet of the air handling unit 26. The outlet C' is connected to the inlet of the first exhaust duct.

[0034] (iii) The second heat accumulator 10 is provided with four interconnected fluid ports. The four ports of the second heat accumulator 10 are respectively connected to outlet C, outlet B”, the inlet of the second exhaust duct, and the inlet of the second supply duct. The outlet of the second exhaust duct is located outdoors, and the outlet of the second supply duct is connected to the fresh air inlet of the air handling unit 26. Outlet C” is connected to the inlet of the second exhaust duct.

[0035] (iv) The solar-assisted heating module includes a solar collector 31, a first circulation pump 32, a hot water storage tank 33, and a second circulation pump 34.

[0036] The working medium in the solar collector 31, the first circulation pump 32, and the hot water storage tank 33 circulates through pipelines; the output end interface of the hot water storage tank 33 is provided with a second three-way valve 30, and the second circulation pump 34 is located between the output end interface of the hot water storage tank 33 and the second three-way valve 30; the input end interface of the hot water storage tank 33 is provided with a first three-way valve 29.

[0037] The first accumulator 4 and the second accumulator 10 are also provided with heat storage body heating pipes; the working medium in the hot water storage tank 33 heats the heat storage bodies in the first accumulator 4 and the second accumulator 10 through the heat storage body heating pipes.

[0038] The first port 29a of the first three-way valve is connected to the output end interface of the heating pipe of the first heat storage body 4, the second port 29b of the first three-way valve is connected to the output end interface of the heating pipe of the second heat storage body 10, and the third port 29c of the first three-way valve is connected to the input end interface of the hot water storage tank 33; the first port 30a of the second three-way valve is connected to the input end interface of the heating pipe of the first heat storage body 4, the second port 30b of the second three-way valve is connected to the input end interface of the heating pipe of the second heat storage body 10, and the third port 30c of the second three-way valve is connected to the output end interface of the second circulating pump 34.

[0039] (v) The heat replenishment control module includes a first temperature controller 27, a second temperature controller 28, a first thermometer 8, a second thermometer 12, a third thermometer 17 and a fourth thermometer 22; the first thermometer 8 is located at the outlet of the first air supply duct, the second thermometer 12 is located at the outlet of the second air supply duct; the third thermometer 17 is located on the second outdoor fresh air circuit behind the second fan 16; and the fourth thermometer 22 is located on the first outdoor fresh air circuit behind the third fan 21.

[0040] The first temperature controller 27 has its input terminals connected to the second thermometer 12 and the third thermometer 17, and its output terminals connected to the first three-way valve 29 and the second three-way valve 30, respectively. The second temperature controller 28 has its input terminals connected to the first thermometer 8 and the fourth thermometer 22, and its output terminals connected to the first three-way valve 29 and the second three-way valve 30, respectively.

[0041] (vi) Operating mode of this system.

[0042] In winter, the system achieves continuous exhaust heat recovery through two alternating heat storage units: one heat storage unit absorbs the waste heat of the exhaust air, while the other releases heat to the fresh air, alternating to preheat the fresh air; the solar heat storage module automatically supplements heat when the heat storage unit is insufficient, increasing the temperature of the fresh air and preventing frost from forming on the total heat exchanger.

[0043] (1) Operation mode 1: Winter heating operation. When the first heat storage unit 4 and the second heat storage unit 10 have sufficient heat storage, the two heat storage units alternately absorb the residual heat of the indoor return air for heat storage and preheat the outdoor fresh air by releasing heat. After the fresh air pretreatment system operates in operation mode 1 for 3 hours, it switches to operation mode 2 for 3 hours, and then switches back to operation mode 1. Operation mode 1 and mode 2 alternate in this way to realize the periodic heat storage and heat release of the first heat storage unit 4 and the second heat storage unit 10.

[0044] ① Running status 1:

[0045] First fan 2, first air valve 3, second air valve 6, fifth air valve 11, second fan 16, seventh air valve 18, and fourth fan 25 are open; third air valve 7, fourth air valve 9, sixth air valve 14, eighth air valve 19, third fan 21, ninth air valve 23, and tenth air valve 24 are closed; first heat accumulator 4 and second heat accumulator 10 are operational.

[0046] Indoor return air passes through the first filter 1, powered by the first fan 2, and then through the first air valve 3 and the first heat accumulator 4. The first heat accumulator 4 absorbs heat from the indoor return air for heat storage, and then passes through the second air valve 6 to be discharged to the outside. Outdoor fresh air passes through the second filter 15, powered by the second fan 16, and passes through the third thermometer 17, the seventh air valve 18, and the second heat accumulator 10 in sequence. The second heat accumulator 10 releases heat to the outdoor fresh air to preheat it. The outdoor fresh air, after being preheated by the second heat accumulator 10, passes through the fifth air valve 11, the second thermometer 12, and the fourth fan 25 in sequence to enter the air handling unit 26. The preheated outdoor fresh air and indoor return air are mixed in the air handling unit 26, and the mixed air is processed by the air handling unit 26 and then sent into the room.

[0047] ② Running status 2:

[0048] First fan 2, third air valve 7, fourth air valve 9, sixth air valve 14, third fan 21, ninth air valve 23, and fourth fan 25 are open; first air valve 3, second air valve 6, fifth air valve 11, second fan 16, seventh air valve 18, eighth air valve 19, and tenth air valve 24 are closed; first heat accumulator 4 and second heat accumulator 10 are operational.

[0049] Indoor return air passes through the first filter 1, powered by the first fan 2, and then through the fourth air valve 9 and the second heat accumulator 10. The second heat accumulator 10 absorbs heat from the exhaust air for heat storage, and then passes through the sixth air valve 14 to be discharged to the outside. Outdoor fresh air passes through the third filter 20, powered by the third fan 21, and passes through the fourth thermometer 22, the ninth air valve 23, and the first heat accumulator 4. The first heat accumulator 4 releases heat to preheat the fresh air. The outdoor fresh air, after being preheated by the first heat accumulator 4, passes through the third air valve 7, the first thermometer 8, and the fourth fan 25 to enter the air handling unit 26. The preheated outdoor fresh air and indoor return air are mixed in the air handling unit 26. The mixed air is then processed by the air handling unit 26 and sent into the room.

[0050] The working fluid in the solar collector 31 absorbs solar heat during the day and is then transported by the first circulation pump 32 to be stored in the hot water storage tank 33 for later use.

[0051] (2) Operation Mode 2: Winter heating operation. When the heat storage of the heat storage device is insufficient, the solar auxiliary heating module automatically supplements the heat based on operation mode 1:

[0052] When the first heat accumulator 4 is insufficient in releasing heat, the first thermometer 8 and the fourth thermometer 22 detect the temperature difference between the fresh air side and the supply air side and transmit the signal to the second temperature controller 28. If the air temperature difference is less than the set temperature difference, it is determined that the heat accumulator is insufficient in releasing heat. The second temperature controller 28 controls the first port 29a and the third port 29c of the first three-way valve, as well as the first port 30a and the third port 30c of the second three-way valve, to open. The working fluid in the hot water storage tank 33 enters the first heat accumulator 4 through the second circulation pump 34 and the second three-way valve 30 to release heat. The working fluid after releasing heat returns to the hot water storage tank 33 through the first three-way valve 29.

[0053] When the second heat storage tank 10 is insufficient in releasing heat, the second thermometer 12 and the third thermometer 17 detect the temperature difference between the fresh air side and the supply air side and transmit the signal to the first temperature controller 27. If the air temperature difference is less than the set temperature difference, it is determined that the heat storage tank is insufficient in releasing heat. The first temperature controller 27 controls the second port 29b and the third port 29c of the first three-way valve, as well as the second port 30b and the third port 30c of the second three-way valve, to open. The working fluid in the hot water storage tank 33 enters the second heat storage tank 10 through the second circulation pump 34 and the second three-way valve 30 to release heat. The working fluid after releasing heat returns to the hot water storage tank 33 through the first three-way valve 29.

[0054] Example 2

[0055] like Figure 2As shown, the present invention provides a cold region anti-frost solar heating dual energy storage air conditioning fresh air pretreatment system, which, in addition to the components provided in Embodiment 1, also includes a first cold storage unit 5 and a second cold storage unit 13.

[0056] The first cold storage 5 is provided with three connected fluid ports. The first cold storage 5 is connected between the first heat storage 4 and the inlet of the first exhaust pipe through two of its ports, and the other port of the first cold storage 5 is connected to the outlet C'.

[0057] The second cold accumulator 13 is provided with three connected fluid ports. The second cold accumulator 13 is connected to the second heat accumulator 10 and the inlet of the second exhaust pipe through two of its ports, and the other port of the second cold accumulator 13 is connected to the outlet C”.

[0058] The operating modes are as follows:

[0059] In winter, the system achieves continuous exhaust heat recovery through two alternating heat storage units: one absorbs waste heat from the exhaust air, while the other releases heat to the fresh air, alternating to preheat the fresh air. The solar thermal storage module automatically supplements heat when the heat storage units are insufficient, increasing the fresh air temperature and preventing frost formation on the total heat exchanger. In summer nights, the system introduces outdoor air for direct cooling, while simultaneously utilizing a cold storage unit to store the coldness in the outdoor air. During the day, the stored coldness is released to pre-cool the fresh air or to handle part of the indoor cooling load. This system, through a dual energy storage mechanism of winter heat storage and summer cold storage combined with solar thermal supplementation, achieves highly efficient energy saving and frost prevention in the pre-treatment of fresh air in cold regions during both winter and summer.

[0060] (1) Operation mode 1: Winter heating operation. When the first heat storage 4 and the second heat storage 10 have sufficient heat storage, the two heat storage 4 and the second heat storage 10 alternately absorb the residual heat of the indoor return air for heat storage and preheat the outdoor fresh air by releasing heat.

[0061] After operating in state 1 for 3 hours, the fresh air pretreatment system switches to state 2 for 3 hours, and then switches back to state 1. State 1 and state 2 alternate in this way to achieve periodic heat storage and release of the first heat storage unit 4 and the second heat storage unit 10. The first cold storage unit 5 and the second cold storage unit 13 do not work and are only used as pipes.

[0062] ① Running status 1:

[0063] First fan 2, first air valve 3, second air valve 6, fifth air valve 11, second fan 16, seventh air valve 18, and fourth fan 25 are open; third air valve 7, fourth air valve 9, sixth air valve 14, eighth air valve 19, third fan 21, ninth air valve 23, and tenth air valve 24 are closed; first heat accumulator 4 and second heat accumulator 10 are working; first cold accumulator 5 and second cold accumulator 13 are not working.

[0064] The indoor return air is powered by the first fan 2 through the first filter 1 and then passes through the first air valve 3 and the first heat accumulator 4. The first heat accumulator 4 absorbs heat from the indoor return air and stores it. After that, the indoor return air is discharged to the outside through the first heat accumulator 4, the first cold storage accumulator 5, and the second air valve 6.

[0065] Outdoor fresh air is powered by the second fan 16 through the second filter 15, and passes through the third thermometer 17, the seventh air valve 18, and the second heat accumulator 10 in sequence. The second heat accumulator 10 releases heat to the outdoor fresh air to preheat it. The outdoor fresh air, after being preheated by the second heat accumulator 10, passes through the fifth air valve 11, the second thermometer 12, and the fourth fan 25 in sequence before entering the air handling unit 26. The preheated outdoor fresh air is mixed with the indoor return air in the air handling unit 26. The mixed air is then processed by the air handling unit 26 and sent into the room.

[0066] ② Running status 2:

[0067] First fan 2, third air valve 7, fourth air valve 9, sixth air valve 14, third fan 21, ninth air valve 23, and fourth fan 25 are open; first air valve 3, second air valve 6, fifth air valve 11, second fan 16, seventh air valve 18, eighth air valve 19, and tenth air valve 24 are closed; first heat accumulator 4 and second heat accumulator 10 are working; first cold accumulator 5 and second cold accumulator 13 are not working.

[0068] Indoor return air passes through the first filter 1, powered by the first fan 2, and then through the fourth air valve 9 and the second heat accumulator 10. The second heat accumulator 10 absorbs heat from the exhaust air for heat storage. The indoor return air passes through the second heat accumulator 10, then through the second cold storage accumulator 13 and the sixth air valve 14 before being discharged to the outside. Outdoor fresh air passes through the third filter 20, powered by the third fan 21, and passes through the fourth thermometer 22, the ninth air valve 23, and the first heat accumulator 4. The first heat accumulator 4 releases heat to preheat the fresh air. The outdoor fresh air, after being preheated by the first heat accumulator 4, passes through the third air valve 7, the first thermometer 8, and the fourth fan 25 before entering the air handling unit 26. The preheated outdoor fresh air and indoor return air are mixed in the air handling unit 26. The mixed air is then processed by the air handling unit 26 and sent into the room.

[0069] The working fluid in the solar collector 31 absorbs solar heat during the day and is then transported by the first circulation pump 32 to be stored in the hot water storage tank 33 for later use.

[0070] (2) Operation mode 2: Winter heating operation. When the heat storage of the heat storage device is insufficient, the solar auxiliary heat supplement module automatically supplements the heat: The principle is the same as the operation mode 2 in Example 1.

[0071] (3) Operation Mode 3: Summer Nighttime Cooling and Cold Storage:

[0072] In the first stage, the third air valve 7, the sixth air valve 14, the second fan 16, the eighth air valve 19, the third fan 21, the ninth air valve 23, and the fourth fan 25 are opened, while the first fan 2, the first air valve 3, the second air valve 6, the fourth air valve 9, the fifth air valve 11, the seventh air valve 18, and the tenth air valve 24 are closed; the second cold accumulator 13 is working; the first heat accumulator 4, the first cold accumulator 5, and the second heat accumulator 10 are not working and are only used as pipelines.

[0073] A portion of the outdoor fresh air enters the second filter 15, powered by the second fan 16, and passes sequentially through the third thermometer 17, the eighth air valve 19, and the second cold storage unit 13. After releasing its cooling capacity in the second cold storage unit 13, the outdoor fresh air is discharged to the outside through the sixth air valve 14. Another portion of the outdoor fresh air enters the third filter 20, powered by the third fan 21, and passes sequentially through the fourth thermometer 22, the ninth air valve 23, the first heat storage unit 4, the third air valve 7, the first thermometer 8, and the fourth fan 25 before entering the air handling unit 26. The outdoor fresh air mixes with the indoor return air, and the mixed air is processed by the air handling unit 26 before being sent into the room.

[0074] In the second stage, after the second cold accumulator 13 has fully stored cold, the second air valve 6, the fifth air valve 11, the second fan 16, the seventh air valve 18, the third fan 21, the tenth air valve 24, and the fourth fan 25 are opened, and the first fan 2, the first air valve 3, the third air valve 7, the fourth air valve 9, the sixth air valve 14, the eighth air valve 19, and the ninth air valve 23 are closed; the first cold accumulator 5 is working, while the first heat accumulator 4, the second heat accumulator 10, and the second cold accumulator 13 are not working and are only used as pipelines.

[0075] A portion of the outdoor fresh air enters the third filter 20, powered by the third fan 21, and passes through the fourth thermometer 22, the tenth air valve 24, and the first cold storage unit 5. After releasing its cooling capacity in the first cold storage unit 5, the fresh air is discharged to the outside through the second air valve 6. Another portion of the outdoor fresh air enters the second filter 15, powered by the second fan 16, and passes through the third thermometer 17, the seventh air valve 18, the second heat storage unit 10, the fifth air valve 11, the second thermometer 12, and the fourth fan 25 before entering the air handling unit 26. The outdoor fresh air mixes with the indoor return air, and the mixed air is processed by the air handling unit 26 before being sent into the room.

[0076] (4) Operating mode 4: Summer daytime cooling:

[0077] In the first stage, the fifth air valve 11, the second air fan 16, the eighth air valve 19, and the fourth air fan 25 are open; the first air fan 2, the first air valve 3, the second air valve 6, the third air valve 7, the fourth air valve 9, the sixth air valve 14, the seventh air valve 18, the third air fan 21, the ninth air valve 23, and the tenth air valve 24 are closed; the second cold accumulator 13 is working; the first heat accumulator 4, the first cold accumulator 5, and the second heat accumulator 10 are not working and are only used as pipelines.

[0078] Outdoor fresh air passes through the second filter 15 in sequence, powered by the second fan 16, and then through the third thermometer 17, the eighth air valve 19, and the second cold storage unit 13. The second cold storage unit 13 releases cold energy to the outdoor fresh air. After passing through the second cold storage unit 13, the outdoor fresh air passes through the second heat storage unit 10 in sequence, the fifth air valve 11, the second thermometer 12, and the fourth fan 25 before entering the air handling unit 26. The outdoor fresh air mixes with the indoor return air, and the mixed air is processed by the air handling unit 26 before being sent into the room.

[0079] In the second stage, after the cold energy in the second cold accumulator 13 has been released, the third air valve 7, the third fan 21, the tenth air valve 24, and the fourth fan 25 are opened, and the first fan 2, the first air valve 3, the second air valve 6, the fourth air valve 9, the fifth air valve 11, the sixth air valve 14, the second fan 16, the seventh air valve 18, the eighth air valve 19, and the ninth air valve 23 are closed; the first cold accumulator 5 is working; the first heat accumulator 4, the second cold accumulator 13, and the second heat accumulator 10 are not working and are only used as pipelines.

[0080] Outdoor fresh air passes through the third filter 20 in sequence, powered by the third fan 21, and then through the fourth thermometer 22, the tenth air valve 24, and the first cold storage unit 5. The first cold storage unit 5 releases cold energy to the outdoor fresh air. After passing through the first cold storage unit 5, the outdoor fresh air passes through the first heat storage unit 4, the third air valve 7, the first thermometer 8, and the fourth fan 25 in sequence before entering the air handling unit 26. The fresh air mixes with the indoor return air, and the mixed air is processed by the air handling unit 26 before being sent into the room.

[0081] (1) The system of the present invention uses two heat accumulators, which are used in a periodic switching manner to perform the functions of absorbing exhaust waste heat and preheating fresh air alternately. When one heat accumulator absorbs exhaust heat for heat storage, the other heat accumulator releases heat to the fresh air. After a set time, the two roles are switched. This cycle is repeated to achieve continuous and stable exhaust heat recovery, effectively avoiding the problem of unstable heat recovery caused by temperature decay of a single heat storage device.

[0082] (2) This invention introduces solar energy as an auxiliary heating method. As a clean and renewable resource, solar energy can provide a supplementary heat source when exhaust waste heat is insufficient. Under the combined effect of exhaust waste heat and solar energy supplementation, the fresh air inlet temperature is effectively increased, thereby inhibiting the occurrence of frost on the total heat exchanger and ensuring the stable and efficient operation of the heat pump system in cold regions.

[0083] (3) In addition, cold regions are characterized by large diurnal temperature variations in summer, with outdoor temperatures typically low at night. This invention fully utilizes this characteristic by adding a cold storage unit to the same device: during summer nights, the cold storage unit is cooled by low-temperature outdoor air, and during the day, the stored cold energy is released to pre-cool fresh air or directly handle part of the indoor cooling load. This design allows the system to effectively utilize natural cold sources in summer while simultaneously preventing frost and preheating in winter, thus improving the annual utilization rate of the equipment and further reducing the overall energy consumption of the system.

[0084] In summary, this invention uses "exhaust heat recovery + solar energy supplementation" to increase the temperature of fresh air to prevent frost formation, achieves continuous and stable heat recovery through "alternating operation of dual heat storage devices", and can also utilize natural cold sources in summer by adding a cold storage device, thus forming a cold-region anti-frost solar energy supplementation dual-energy storage air conditioning fresh air pretreatment system.

[0085] As described above, although the invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the invention itself. Various changes in form and detail may be made without departing from the spirit and scope of the invention.

Claims

1. A cold-region anti-frost solar-powered heating dual-energy storage air conditioning fresh air pretreatment system, characterized in that, The fresh air pretreatment system includes a first heat storage unit (4), a second heat storage unit (10), an air handling unit (26), a solar-assisted heating module, and a heating control module; In winter, the first heat storage unit (4) and the second heat storage unit (10) alternately absorb the residual heat of the indoor return air for heat storage and preheat the outdoor fresh air by releasing heat; the indoor return air and the preheated outdoor fresh air are transported to the air handling unit (26), and after being processed by the air handling unit (26), they are sent into the room. The heat replenishment control module, based on the temperature before and after the outdoor fresh air is preheated, controls the solar-assisted heat replenishment module to store heat in the first heat accumulator (4) or the second heat accumulator (10) when the heat output of the first heat accumulator (4) or the second heat accumulator (10) is insufficient.

2. The fresh air pretreatment system according to claim 1, characterized in that, The fresh air pretreatment system also includes an indoor return air circuit, a first outdoor fresh air circuit, and a second outdoor fresh air circuit; The indoor return air circuit is provided with inlet A, outlet B, and outlet C, with the inlet located indoors; the first outdoor fresh air circuit is provided with inlet A', outlet B', and outlet C', with inlet A' located outdoors; the second outdoor fresh air circuit is provided with inlet A”, outlet B”, and outlet C”, with inlet A” located outdoors; the air handling unit (26) has a fresh air inlet and an indoor return air inlet; The first heat accumulator (4) is provided with four interconnected fluid ports. The four ports of the first heat accumulator (4) are respectively connected to outlet B, outlet B', the inlet of the first exhaust duct, and the inlet of the first supply duct. The outlet of the first exhaust duct is located outdoors, and the outlet of the first supply duct is connected to the fresh air inlet of the air handling unit (26). The outlet C' is connected to the inlet of the first exhaust duct. The second heat accumulator (10) is provided with four interconnected fluid ports. The four ports of the second heat accumulator (10) are respectively connected to outlet C, outlet B”, the inlet of the second exhaust duct, and the inlet of the second supply duct. The outlet of the second exhaust duct is located outdoors, and the outlet of the second supply duct is connected to the fresh air inlet of the air handling unit (26). Outlet C” is connected to the inlet of the second exhaust duct.

3. The fresh air pretreatment system according to claim 2, characterized in that, The outlets B, C, B', C', B”, C”, the inlet of the first exhaust duct, the inlet of the second exhaust duct, the inlet of the first supply duct, and the inlet of the second supply duct are all equipped with a first air valve (3), a fourth air valve (9), a ninth air valve (23), a tenth air valve (24), a seventh air valve (18), an eighth air valve (19), a second air valve (6), a sixth air valve (14), a third air valve (7), and a fifth air valve (11).

4. The fresh air pretreatment system according to claim 3, characterized in that, The indoor return air circuit is equipped with a first fan (2), the first outdoor fresh air circuit is equipped with a third fan (21), the second outdoor fresh air circuit is equipped with a second fan (16), and the fresh air inlet of the air handling unit (26) is equipped with a fourth fan (25).

5. The fresh air pretreatment system according to claim 4, characterized in that, The solar-assisted heating module includes a solar collector (31), a first circulation pump (32), a hot water storage tank (33), and a second circulation pump (34). The working medium in the solar collector (31), the first circulation pump (32), and the hot water storage tank (33) circulates through pipelines; the first heat storage tank (4) and the second heat storage tank (10) are also provided with heat storage body heating pipelines; the working medium in the hot water storage tank (33) heats the heat storage body in the first heat storage tank (4) and the second heat storage tank (10) through the heat storage body heating pipelines.

6. The fresh air pretreatment system according to claim 5, characterized in that, The output port of the hot water storage tank (33) is connected to the input port of the heat storage body heating pipe of the first heat storage device (4) and the second heat storage device (10) through the second three-way valve (30); a second circulation pump (34) is provided between the output port of the hot water storage tank 33 and the second three-way valve (30). The input end of the hot water storage tank (33) is connected to the output end interface of the heat storage body heating pipe of the first heat storage device (4) and the second heat storage device (10) through the first three-way valve (29).

7. The fresh air pretreatment system according to claim 6, characterized in that, The heat replenishment control module includes a first temperature controller (27), a second temperature controller (28), a first thermometer (8), a second thermometer (12), a third thermometer (17), and a fourth thermometer (22); the first thermometer (8) is located at the outlet of the first air supply duct, the second thermometer (12) is located at the outlet of the second air supply duct; the third thermometer (17) is located on the second outdoor fresh air circuit behind the second fan (16); and the fourth thermometer (22) is located on the first outdoor fresh air circuit behind the third fan (21). The input terminals of the first temperature controller (27) are connected to the second thermometer (12) and the third thermometer (17), respectively, and the output terminals are connected to the first three-way valve (29) and the second three-way valve (30), respectively; the input terminals of the second temperature controller (28) are connected to the first thermometer (8) and the fourth thermometer (22), respectively, and the output terminals are connected to the first three-way valve (29) and the second three-way valve (30), respectively.

8. The fresh air pretreatment system according to claim 1, characterized in that, The fresh air pretreatment system also includes a first cold storage unit (5) and a second cold storage unit (13). In summer, the first cold storage unit (5) and the second cold storage unit (13) use the low temperature air at night to charge the cold air, and release the stored cold air during the day to pre-cool the outdoor fresh air. The indoor return air and the pre-cooled outdoor fresh air are transported to the air handling unit (26), and after being processed by the air handling unit (26), they are sent into the room.

9. The fresh air pretreatment system according to claim 7, characterized in that, The fresh air pretreatment system also includes a first cold storage unit (5) and a second cold storage unit (13). The first cold storage (5) is provided with three connected fluid ports. The first cold storage (5) is connected between the first heat storage (4) and the inlet of the first exhaust pipe through two of its ports. The other port outlet C' of the first cold storage (5) is connected. The second cold storage (13) has three connected fluid ports. The second cold storage (13) is connected between the second heat storage (10) and the second exhaust pipe inlet through two of its ports. The other port of the second cold storage (13) is connected to the outlet C”.

10. The fresh air pretreatment system according to claim 9, characterized in that, The operating modes of the fresh air pretreatment system are as follows: Operating mode 1: Winter heating operation, the first heat storage unit (4) and the first heat storage unit (10) alternately absorb the residual heat of indoor return air for heat storage and preheat the outdoor fresh air by releasing heat; Operating mode 2: Winter heating operation. When the first heat storage device (4) or the first heat storage device (10) is insufficient, the solar auxiliary heating module automatically supplements the heat of the first heat storage device (4) or the first heat storage device (10) based on operating mode 1. Operating mode 3: During summer nighttime cooling and cold storage, in the first stage, outdoor fresh air enters the second cold storage unit 13, releases cold energy in the second cold storage unit (13) and is then discharged to the outside; outdoor fresh air and indoor return air are processed by the air handling unit (26) and then sent into the room; In the second stage, a portion of the outdoor fresh air is discharged to the outside after releasing its cooling capacity in the first cold storage unit (5); another portion of the outdoor fresh air and indoor return air are processed by the air handling unit (26) and then sent into the room. Operating mode 4: During summer daytime cooling, in the first stage, outdoor fresh air enters the second cold storage unit (13), the second cold storage unit (13) releases cold energy to the outdoor fresh air, indoor return air and outdoor fresh air treated by the second cold storage unit (13) enter the air handling unit (26) for treatment and then send it into the room. In the second stage, the outdoor fresh air enters the first cold storage unit (5), the first cold storage unit (5) releases cold energy to the outdoor fresh air, and the indoor return air and the outdoor fresh air treated by the first cold storage unit (5) enter the air handling unit (26) for further treatment and then are sent into the room.

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