Multi-energy complementary heat supply system and method based on air source heat pump, ground source heat pump and heat storage water tank

Abstract

The invention provides a multi-energy complementary heat supply system and method based on an air source heat pump, a ground source heat pump and a heat storage water tank, belongs to the technical field of heating, ventilation and air conditioning, and solves the problem that the operation scheme design in a specific scene still has a blank. The system comprises a ground source heat pump, a buried pipe, a heat storage water tank, an air source heat pump, a fan, an air-water heat exchanger, a plate heat exchanger and a heat consumer and has seven operation modes, and different system operation modes are adopted for different outdoor temperature intervals. By establishing a correlation model of an environment temperature, a system connection form and equipment start-stop, the energy supply efficiency is improved, the operation cost is reduced, and carbon emission is reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of heating, ventilation and air conditioning, and particularly relates to a multi-energy complementary heating system and method based on an air source heat pump, a ground source heat pump and a heat storage tank. BACKGROUND

[0002] In cold regions, areas such as high-speed service areas and airports far from urban central heating pipe networks generally use traditional heating modes of gas boilers combined with radiators in winter. This heating mode not only aggravates carbon emissions, but also has high operating costs. Introducing clean energy and multi-energy complementary systems has become a key path to optimizing the heating mode in this scenario. Existing heating systems generally use air source heat pumps and / or ground source heat pumps. However, whether an air source heat pump or a ground source heat pump is used alone or a "ground source heat pump + air source heat pump" multi-energy complementary mode is used, there are deficiencies, especially in cold regions. The specific deficiencies are as follows: 1. The air source heat pump has the advantages of flexible installation and low initial investment, but its heating capacity is directly related to the outdoor temperature. In low-temperature environments, the outdoor heat exchanger is prone to frost, which not only reduces its heat exchange efficiency, but also causes the defrosting program to start frequently, resulting in a decrease in system energy efficiency (COP). In cold regions, this problem is even more prominent, and in actual use, problems such as insufficient heating or equipment freezing may occur.

[0003] 2. The ground source heat pump has the characteristics of high efficiency and stability, and is not affected by the dramatic fluctuations of outdoor ambient temperature, but there is a risk of heat imbalance in long-term operation. Long-term operation of the system in a single mode may cause the soil temperature in the buried pipe area to continuously decrease or increase, forming a "heat island" or "cold island" effect, which reduces the heat exchange efficiency and has a cumulative effect on the regional microclimate or groundwater circulation.

[0004] 3. Multi-energy complementary system integrates multiple energy forms to realize the collaborative and optimized utilization of energy. The multi-energy complementary mode of "ground source heat pump + air source heat pump" can improve the low-temperature energy efficiency of the system and alleviate the problem of soil heat imbalance. However, most systems use a single start-stop operation strategy and do not fully consider the performance differences of different equipment output ratios. At the same time, there is a lack of optimization and adjustment of system operation mode under different environmental temperature conditions, which makes it difficult for the system to perform optimally in different outdoor temperature intervals. For example, the patent application with the application number CN202323449791.X discloses an air source heat pump and ground source heat pump coupled energy supply device, which improves the energy efficiency of the system by coupling the air source heat pump unit and the ground source heat pump unit. The patent application with the application number CN202421130088.4 discloses a system for heating using compressed air energy storage compression heat coupled with a ground source heat pump, which utilizes the compressed air energy storage system, ground source heat pump system related equipment and pipelines to realize heating while improving the utilization efficiency of waste heat and the energy efficiency of the compressed air energy storage system. The patent application with the application number CN202421215114.3 discloses a dual-source coupled heat pump system, which proposes a heat source system including an air source heat pump unit, a water source heat pump unit, an energy storage water tank, a water storage tank, and a cooling tower, which can realize single and dual-source system switching and various heating (cooling) modes. The schemes disclosed in these patent applications do not propose specific operation schemes according to changes in outdoor environmental temperature, and there is still a gap in the design of operation schemes for specific scenarios. SUMMARY

[0005] Therefore, in order to solve the problem that there is still a gap in the design of operation schemes for specific scenarios in the existing multi-energy complementary heating schemes, the present application proposes a multi-energy complementary heating system and method based on an air source heat pump, a ground source heat pump, and a heat storage water tank.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical scheme: A multi-energy complementary heating system based on an air source heat pump, a ground source heat pump, and a heat storage water tank, comprising: a ground source heat pump, a buried pipe, and a heat storage water tank, the water inlet end of the buried pipe is communicated with the heat storage water tank through a first valve, a first water pump, a third valve, and a second water pump in sequence, the water outlet end of the buried pipe is communicated with the heat storage water tank through a second valve and a fourth valve in sequence, the left water outlet end of the ground source heat pump is communicated with the water inlet end of the first water pump, and the left water inlet end of the ground source heat pump is communicated with the water outlet end of the second valve; The air source heat pump, the fan and the air-water heat exchanger, the left water outlet end of the air-water heat exchanger is sequentially communicated with the right water inlet end of the ground source heat pump through the seventh valve and the third water pump, the left water inlet end of the air-water heat exchanger is communicated with the right water outlet end of the ground source heat pump through the eighth valve, the right water inlet end of the air-water heat exchanger is communicated with the left water outlet end of the air source heat pump through the twelfth valve, the right water outlet end of the air-water heat exchanger is communicated with the left water inlet end of the air source heat pump through the eleventh valve, and the fan is connected with the air source heat pump; the water inlet end of the first water pump is communicated with the water outlet end of the third water pump through the fifth valve, and the water outlet end of the second valve is communicated with the water inlet end of the eighth valve through the sixth valve; The plate heat exchanger and the heat user, the left water outlet end of the plate heat exchanger is sequentially communicated with the right side first interface of the air source heat pump through the fourth water pump and the fifteenth valve, and the left water inlet end of the plate heat exchanger is communicated with the right side second interface of the air source heat pump through the sixteenth valve; the water inlet end of the third water pump is communicated with the water outlet end of the fourth water pump through the ninth valve, the right water outlet end of the ground source heat pump and the water outlet end of the sixth valve are both communicated with the left water inlet end of the plate heat exchanger through the tenth valve, the water inlet end of the first water pump is communicated with the water outlet end of the fifteenth valve through the fourteenth valve and the fifth water pump, and the water outlet end of the second valve is communicated with the water inlet end of the sixteenth valve through the thirteenth valve; the water outlet end of the heat user is communicated with the right water inlet end of the plate heat exchanger, and the water inlet end of the heat user is communicated with the right water outlet end of the plate heat exchanger.

[0007] The application also provides a multi-energy complementary heating method based on an air source heat pump, a ground source heat pump and a heat storage water tank. The multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank has seven operation modes, namely a first operation mode, a second operation mode, a third operation mode, a fourth operation mode, a fifth operation mode, a sixth operation mode and a seventh operation mode. According to the month, the whole year is divided into a transition season, a heating season and a refrigeration season. According to the outdoor environment temperature, the heating season is divided into a first stage, a second stage, a third stage, a fourth stage and a fifth stage. When the current is in the transition season, the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank adopts the first operation mode. When the current is in the first stage, the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank adopts the second operation mode. When the current is in the second stage, the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank adopts the third operation mode. When the current is in the third stage, the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank adopts the fourth operation mode. When the system is in the fourth stage, the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage tank adopts a fifth operation mode; When the system is in the fifth stage, the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage tank adopts a sixth operation mode; When the system is in the refrigeration season, the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage tank adopts a seventh operation mode.

[0008] As a preferred scheme of the above multi-energy complementary heating method based on the air source heat pump, the ground source heat pump and the heat storage tank, October to April of next year is the heating season, May to June and September to October is the transition season, June to August is the refrigeration season, when the outdoor environment temperature is in the range of -3 to -3℃, it is the first stage, when the outdoor environment temperature is in the range of -4 to -10℃, it is the second stage, when the outdoor environment temperature is in the range of -11 to -17℃, it is the third stage, when the outdoor environment temperature is in the range of -18 to -25℃, it is the fourth stage, and when the outdoor environment temperature is lower than -25℃, it is the fifth stage.

[0009] As a preferred scheme of the above multi-energy complementary heating method based on the air source heat pump, the ground source heat pump and the heat storage tank, when the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage tank adopts the first operation mode, the first valve, the second valve, the third valve and the fourth valve are all opened, other valves are all closed, and the heat storage tank supplies heat to the soil through heat exchange with the buried pipe.

[0010] As a preferred scheme of the above multi-energy complementary heating method based on the air source heat pump, the ground source heat pump and the heat storage tank, when the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage tank adopts the second operation mode, the eleventh valve, the twelfth valve, the fifteenth valve and the sixteenth valve are all opened, other valves are all closed, and the air source heat pump operates alone to provide heat to the heat user.

[0011] As a preferred scheme of the above multi-energy complementary heating method based on the air source heat pump, the ground source heat pump and the heat storage tank, when the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage tank adopts the third operation mode, the first valve, the second valve, the seventh valve, the eighth valve, the eleventh valve, the twelfth valve, the fifteenth valve and the sixteenth valve are all opened, other valves are all closed, and the ground source heat pump assists the air source heat pump to operate to provide heat to the heat user.

[0012] As a preferred scheme of the above-mentioned multi-energy complementary heating method based on the air source heat pump, the ground source heat pump and the heat storage water tank, when the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank adopts the fourth operation mode, the first valve, the second valve, the ninth valve, the tenth valve, the eleventh valve, the twelfth valve, the thirteenth valve and the fourteenth valve are all opened, other valves are all closed, the air source heat pump assists the ground source heat pump to operate, and heat is provided to the heat user.

[0013] As a preferred scheme of the above-mentioned multi-energy complementary heating method based on the air source heat pump, the ground source heat pump and the heat storage water tank, when the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank adopts the fifth operation mode, the first valve, the second valve, the ninth valve and the tenth valve are all opened, other valves are all closed, and the ground source heat pump operates alone to provide heat to the heat user.

[0014] As a preferred scheme of the above-mentioned multi-energy complementary heating method based on the air source heat pump, the ground source heat pump and the heat storage water tank, when the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank adopts the sixth operation mode, the first valve, the second valve, the third valve, the fourth valve, the ninth valve and the tenth valve are all opened, other valves are all closed, and the ground source heat pump and the heat storage water tank jointly provide heat to the heat user.

[0015] As a preferred scheme of the above-mentioned multi-energy complementary heating method based on the air source heat pump, the ground source heat pump and the heat storage water tank, when the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank adopts the seventh operation mode, the first valve, the second valve, the fifth valve, the sixth valve, the ninth valve and the tenth valve are all opened, other valves are all closed, and the buried pipe exchanges heat with the heat user.

[0016] Compared with the prior art, the multi-energy complementary heating system and method based on the air source heat pump, the ground source heat pump and the heat storage water tank have the following beneficial effects: (1) Renewable energy such as geothermal energy and air energy is used as the main source to replace traditional high-pollution gas boilers, and the consumption of fossil energy and carbon emissions are reduced. (2) The system has seven switchable energy connection forms, the most efficient system operation strategy and the corresponding connection form are determined according to the months of the year and the outdoor temperature change, the system is ensured to be in the high-efficiency operation state at all times, the air source heat pump, the ground source heat pump and the heat storage water tank are fully coordinated, the energy efficiency, economy and low-carbon target are considered in combination with the valley electricity policy, and the system is especially suitable for full-scene use.

[0017] (3) The air source heat pump and the ground source heat pump are combined with the valley electricity policy, and are suitable for severe cold regions and can reduce operation cost. The air source heat pump is high in efficiency in moderate weather, reduces the heat extraction pressure of the ground source heat pump, the ground source heat pump is stable in energy supply in extremely cold weather, avoids low temperature attenuation of the air source heat pump in energy supply, the heat storage tank can supplement peak heat load, and is suitable for severe cold regions.

[0018] (4) Great importance is attached to ground heat recharge, the problem of soil heat imbalance caused by unbalanced cold and heat load in severe cold regions in winter and summer is avoided, the soil ecology is protected, and the requirement of sustainable green development is met. BRIEF DESCRIPTION OF DRAWINGS

[0019] The drawings constituting a part of this application provide further understanding of the application, the schematic embodiments of the application and the description thereof are used to explain the application, and do not constitute improper limitation on the application. In the drawings: Figure 1 is a structural schematic diagram of a multi-energy complementary heat supply system based on an air source heat pump, a ground source heat pump and a heat storage tank provided by the embodiment of the application; Figure 2 is a time period distribution schematic diagram of a multi-energy complementary heat supply system based on an air source heat pump, a ground source heat pump and a heat storage tank provided by the embodiment of the application; Figure 3 is a schematic diagram of a multi-energy complementary heat supply system based on an air source heat pump, a ground source heat pump and a heat storage tank in a first operation mode provided by the embodiment of the application; Figure 4 is a schematic diagram of a multi-energy complementary heat supply system based on an air source heat pump, a ground source heat pump and a heat storage tank in a second operation mode provided by the embodiment of the application; Figure 5 is a schematic diagram of a multi-energy complementary heat supply system based on an air source heat pump, a ground source heat pump and a heat storage tank in a third operation mode provided by the embodiment of the application; Figure 6 is a schematic diagram of a multi-energy complementary heat supply system based on an air source heat pump, a ground source heat pump and a heat storage tank in a fourth operation mode provided by the embodiment of the application; Figure 7 is a schematic diagram of a multi-energy complementary heat supply system based on an air source heat pump, a ground source heat pump and a heat storage tank in a fifth operation mode provided by the embodiment of the application; Figure 8 is a schematic diagram of a multi-energy complementary heat supply system based on an air source heat pump, a ground source heat pump and a heat storage tank in a sixth operation mode provided by the embodiment of the application; Figure 9is a schematic view of a multi-energy complementary heating system based on an air source heat pump, a ground source heat pump and a heat storage water tank in a seventh operation mode according to specific embodiments of the present application.

[0020] In the figure: 1, first valve; 2, second valve; 3, third valve; 4, fourth valve; 5, fifth valve; 6, sixth valve; 7, seventh valve; 8, eighth valve; 9, ninth valve; 10, tenth valve; 11, eleventh valve; 12, twelfth valve; 13, thirteenth valve; 14, fourteenth valve; 15, fifteenth valve; 16, sixteenth valve; 17, buried pipe; 18, heat storage water tank; 19, ground source heat pump; 20, air-water heat exchanger; 21, air source heat pump; 22, fan; 23, plate heat exchanger; 24, first water pump; 25, second water pump; 26, third water pump; 27, fifth water pump; 28, fourth water pump; 29, heat user. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict, and the described embodiments are only part of the embodiments of the present application, not all the embodiments.

[0022] In the description of the present application, unless otherwise explicitly specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements or the interaction relationship between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0023] In the present application, unless otherwise explicitly specified and limited, the "upper" or "lower" of the first feature to the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the "upper", "upper" and "upper" of the first feature to the second feature include that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "below", "below" and "below" of the first feature to the second feature include that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0024] In the description of the present embodiment, the terms "upper", "lower", "right", and the like, orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" are only used to distinguish in the description, and have no special meaning.

[0025] Referring to Figures 1-9 To illustrate the present embodiment, the present application proposes a multi-energy complementary heating system and method based on air source heat pump, ground source heat pump and heat storage tank, which is suitable for the areas far away from the urban central heating pipe network in severe cold regions and operates in cooperation with the valley electricity policy. Different system operation modes are proposed for different outdoor temperature intervals. By establishing the correlation model of environmental temperature and system connection form, equipment start-stop, the energy supply efficiency is improved, the operation cost is reduced, and the carbon emission is reduced.

[0026] The multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank comprises a ground source heat pump 19, a buried pipe 17, a heat storage water tank 18, an air source heat pump 21, a fan 22, a water-air heat exchanger 20, a plate heat exchanger 23 and a heat user 29, the water inlet end of the buried pipe 17 is communicated with the heat storage water tank 18 in sequence through a first valve 1, a first water pump 24, a third valve 3 and a second water pump 25, the water outlet end of the buried pipe 17 is communicated with the heat storage water tank 18 in sequence through a second valve 2 and a fourth valve 4, the left water outlet end of the ground source heat pump 19 is communicated with the water inlet end of the first water pump 24, and the left water inlet end of the ground source heat pump 19 is communicated with the water outlet end of the second valve 2; the left water outlet end of the water-air heat exchanger 20 is communicated with the right water inlet end of the ground source heat pump 19 in sequence through a seventh valve 7 and a third water pump 26, the left water inlet end of the water-air heat exchanger 20 is communicated with the right water outlet end of the ground source heat pump 19 through an eighth valve 8, the right water inlet end of the water-air heat exchanger 20 is communicated with the left water outlet end of the air source heat pump 21 through a twelfth valve 12, the right water outlet end of the water-air heat exchanger 20 is communicated with the left water inlet end of the air source heat pump 21 through an eleventh valve 11, and the fan 22 is connected with the air source heat pump 21; the water inlet end of the first water pump 24 is communicated with the water outlet end of the third water pump 26 through a fifth valve 5, and the water outlet end of the second valve 2 is communicated with the water inlet end of the eighth valve 8 through a sixth valve 6; the left water outlet end of the plate heat exchanger 23 is communicated with the right first interface of the air source heat pump 21 in sequence through a fourth water pump 28 and a fifteenth valve 15, the left water inlet end of the plate heat exchanger 23 is communicated with the right second interface of the air source heat pump 21 through a sixteenth valve 16; the water inlet end of the third water pump 26 is communicated with the water outlet end of the fourth water pump 28 through a ninth valve 9, the right water outlet end of the ground source heat pump 19 and the water outlet end of the sixth valve 6 are both communicated with the left water inlet end of the plate heat exchanger 23 through a tenth valve 10, the water inlet end of the first water pump 24 is communicated with the water outlet end of the fifteenth valve 15 through a fourteenth valve 14 and a fifth water pump 27, and the water outlet end of the second valve 2 is communicated with the water inlet end of the sixteenth valve 16 through a thirteenth valve 13; the water outlet end of the heat user 29 is communicated with the right water inlet end of the plate heat exchanger 23, and the water inlet end of the heat user 29 is communicated with the right water outlet end of the plate heat exchanger 23.

[0027] The multi-energy complementary heating method based on the air source heat pump, the ground source heat pump and the heat storage water tank adopts the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank, and comprises the following steps. The multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage water tank has seven operation modes, namely a first operation mode, a second operation mode, a third operation mode, a fourth operation mode, a fifth operation mode, a sixth operation mode and a seventh operation mode.

[0028] According to the month, the whole year is divided into transition season, heating season and cooling season. Specifically: October ~ next April is the heating season; May ~ June and September ~ October is the transition season; June ~ August is the cooling season.

[0029] According to the outdoor environment temperature, the heating season is divided into first stage, second stage, third stage, fourth stage and fifth stage. When the outdoor environment temperature is in the range of 3 ~-3℃, it is the first stage; when the outdoor environment temperature is in the range of-4 ~-10℃, it is the second stage; when the outdoor environment temperature is in the range of-11 ~-17℃, it is the third stage; when the outdoor environment temperature is in the range of-18 ~-25℃, it is the fourth stage; when the outdoor environment temperature is lower than-25℃, it is the fifth stage.

[0030] As shown in Figure 2 According to the change of heat load from the early stage to the end of the heating season, the heating season is further divided into t1 to t2, t2 to t3, t3 to t4, t4 to t5, t5 to t6, t6 to t7, t7 to t8, t8 to t9 and t9 to t10, a total of nine time periods. The heat load gradually increases from the beginning of heating to the maximum in the middle of heating t5 to t6 stage, and then gradually decreases to the end of heating. Among them, t1 to t2 and t9 to t10 time period is the first stage, t2 to t3 and t8 to t9 time period is the second stage, t3 to t4 and t7 to t8 time period is the third stage, t4 to t5 and t6 to t7 time period is the fourth stage; t5 to t6 time period is the fifth stage.

[0031] Figure 2 Among them, the transition season is t0 to t1 and t10 to t11 time period, and the cooling season is t11 to t12 time period.

[0032] According to the month and the outdoor environment temperature, the operation mode of the multi-energy complementary heating system based on air source heat pump, ground source heat pump and heat storage tank is selected: In the transition season, the heat storage tank 18 is used to store heat at night during the valley electricity period, and the soil is heated by the heat storage tank 18. During the heating season, the air source heat pump 21 is started at the beginning of heating t1 and stopped temporarily at t4, and then started again at t7 and stopped at t10, which is the end of the heating season. The air source heat pump 21 is in full power operation stage during the time period of t1 to t3 and t8 to t10, and in auxiliary heating stage during the time period of t3 to t4 and t5 to t6. The air source heat pump 21 is stopped during the time period of t4 to t7, which is the extreme low temperature period in the middle of heating. The ground source heat pump 19 is started at t2 and stopped at t9. The ground source heat pump 19 is in auxiliary heating stage during the time period of t2 to t3 and t8 to t9, and in full power operation stage during the time period of t3 to t8. During the time period of t5 to t6, the ground source heat pump 19 cannot meet the heating demand alone, and the heat storage tank 18 is used to ensure the heating demand. The heat storage tank 18 is used to store heat at night during the valley electricity period. In the cooling season, the buried pipe 17 and the indoor heat exchange are used to realize active cooling and supplement heat to the soil.

[0033] Specifically, when the current is in the transition season, that is, during the time period of t0 to t1 and t10 to t11, the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage tank adopts the first operation mode. When the first operation mode is adopted, the first valve 1, the second valve 2, the third valve 3 and the fourth valve 4 are all opened, and other valves are all closed. The heat storage tank 18 supplements heat to the soil through heat exchange with the buried pipe 17. The heat storage tank 18 supplements heat to the ground source to alleviate the imbalance of heat extraction and rejection of the soil in winter and summer. The heat storage tank 18 is started to heat at night during the valley electricity period to realize low-cost heat storage.

[0034] Specifically, when the current is in the first stage, that is, during the time period of t1 to t2 and t9 to t10, the multi-energy complementary heating system based on the air source heat pump, the ground source heat pump and the heat storage tank adopts the second operation mode. When the second operation mode is adopted, the eleventh valve 11, the twelfth valve 12, the fifteenth valve 15 and the sixteenth valve 16 are all opened, and other valves are all closed. The air source heat pump 21 runs alone to provide heat to the heat user 29. At this time, it is the beginning and end of the heating season, the environmental temperature is high, and the outdoor environmental temperature is in the range of 3~-3℃. The air source heat pump 21 has high COP and heating capacity, so the air source heat pump 21 is used alone for heating.

[0035] Specifically, the current is in the second stage, that is, in the t2 to t3 and t8 to t9 time period, the multi-energy complementary heating system based on air source heat pump, ground source heat pump and heat storage tank adopts the third operation mode. When the third operation mode is adopted, the first valve 1, the second valve 2, the seventh valve 7, the eighth valve 8, the eleventh valve 11, the twelfth valve 12, the fifteenth valve 15 and the sixteenth valve 16 are all opened, and the other valves are all closed. The ground source heat pump 19 assists the air source heat pump 21 to operate, and provides heat to the heat user 29. At this time, the outdoor environment temperature is slightly low, in the range of-4~ -10℃, and the high-temperature hot water prepared by the ground source heat pump 19 is used to preheat the inlet air of the air source heat pump 21, so as to improve the evaporation temperature and the COP of the air source heat pump 21, that is, the ground source heat pump 19 assists the air source heat pump 21 to heat.

[0036] Specifically, the current is in the third stage, that is, in the t3 to t4 and t7 to t8 time period, the multi-energy complementary heating system based on air source heat pump, ground source heat pump and heat storage tank adopts the fourth operation mode. When the fourth operation mode is adopted, the first valve 1, the second valve 2, the ninth valve 9, the tenth valve 10, the eleventh valve 11, the twelfth valve 12, the thirteenth valve 13 and the fourteenth valve 14 are all opened, and the other valves are all closed. The air source heat pump 21 assists the ground source heat pump 19 to operate, and provides heat to the heat user 29. At this time, the outdoor environment temperature becomes lower, in the range of-11~ -17℃, and the air source heat pump 21 assists the ground source heat pump 19. The low-temperature hot water prepared by the air source heat pump 21 improves the evaporation temperature of the ground source heat pump 19, increases the heating capacity and COP of the ground source heat pump 19, and can also be used to adjust the operation peak value of the ground heat exchanger 17, reduces the heat extraction amount of the ground source heat pump 19, and guarantees the heat balance.

[0037] Specifically, the current is in the fourth stage, that is, in the t4 to t5 and t6 to t7 time period, the multi-energy complementary heating system based on air source heat pump, ground source heat pump and heat storage tank adopts the fifth operation mode. When the fifth operation mode is adopted, the first valve 1, the second valve 2, the ninth valve 9 and the tenth valve 10 are all opened, and the other valves are all closed. The ground source heat pump 19 operates alone to provide heat to the heat user 29. At this time, it is in the middle of heating, and the outdoor environment temperature is in the range of-18~ -25℃. At this time, the COP of the air source heat pump 21 is very low, the air source heat pump 21 is closed, and the ground source heat pump 19 is used for heating alone.

[0038] Specifically, the current is in the fifth stage, that is, in the t5 to t6 time period, the multi-energy complementary heating system based on air source heat pump, ground source heat pump and heat storage water tank adopts the sixth operation mode. When the sixth operation mode is adopted, the first valve 1, the second valve 2, the third valve 3, the fourth valve 4, the ninth valve 9 and the tenth valve 10 are all opened, and other valves are all closed. The ground source heat pump 19 and the heat storage water tank 18 jointly provide heat to the heat user 29. At this time, it is an extremely low temperature condition, and the outdoor environment temperature is lower than-25℃. At this time, the air source heat pump 21COP is very low, and the ground source heat pump 19 alone cannot meet the demand of heat load. Therefore, the ground source heat pump 19 and the heat storage water tank 18 jointly provide heat to the indoor heat user 29, and the heat storage water tank 18 stores heat during valley electricity, thereby achieving auxiliary heating.

[0039] Specifically, the current is in the fifth stage, that is, in the t5 to t6 time period, the multi-energy complementary heating system based on air source heat pump, ground source heat pump and heat storage water tank adopts the sixth operation mode. When the sixth operation mode is adopted, the first valve 1, the second valve 2, the third valve 3, the fourth valve 4, the ninth valve 9 and the tenth valve 10 are all opened, and other valves are all closed. The ground source heat pump 19 and the heat storage water tank 18 jointly provide heat to the heat user 29. At this time, it is an extremely low temperature condition, and the outdoor environment temperature is lower than-25℃. At this time, the air source heat pump 21COP is very low, and the ground source heat pump 19 alone cannot meet the demand of heat load. Therefore, the ground source heat pump 19 and the heat storage water tank 18 jointly provide heat to the indoor heat user 29, and the heat storage water tank 18 stores heat during valley electricity, thereby achieving auxiliary heating.

[0040] The multi-energy complementary heating system and method based on an air source heat pump, a ground source heat pump and a heat storage water tank is suitable for a region far from a city central heating pipe network in a severe cold area. The system has seven switchable energy connection forms. According to the month and outdoor temperature changes throughout the year, the most efficient system operation strategy and the corresponding connection form are determined. In the first operation mode, the heat storage water tank 18 supplies heat to the soil. In the second operation mode, the air source heat pump 21 alone supplies heat. In the third operation mode, the ground source heat pump 19 preheats the air source heat pump 21 inlet air in the air-water heat exchanger 20 to assist the air source heat pump 21 to supply heat. In the fourth operation mode, the air source heat pump 21 provides low-temperature heat water as a low-temperature heat source to assist the ground source heat pump 19 to generate heat. In the fifth operation mode, the ground source heat pump 19 alone supplies heat. In the sixth operation mode, the ground source heat pump 19 and the heat storage water tank 18 jointly supply cold quantity to the indoor of the heat user 29. In the seventh operation mode, the buried pipe 17 heat exchanger directly supplies cold quantity to the indoor. The fifth operation mode and the second operation mode are traditional heat pump connection forms, which can be switched by single start-stop. For the third operation mode of the ground source assisted air source, the evaporation temperature of the air source heat pump 21 is improved, and the COP of the air source heat pump 21 is improved. The air source heat pump 21 occupies a dominant position and bears a larger load ratio, which can alleviate the poor heating performance of the air source heat pump 21 in a low-temperature environment. For the fourth operation mode of the air source heat pump 21 assisted ground source heat pump 19, the air source heat pump 21 is used as a low-temperature heat source to assist the ground source heat pump 19 to operate, thereby increasing the heating capacity and COP of the ground source heat pump 19. The ground source heat pump 19 occupies a dominant position and bears a larger load ratio. The sixth operation mode is that the ground source heat pump 19 and the heat storage water tank 18 jointly supply heat to the indoor. In the case of extremely low temperature, the air source heat pump 21 cannot operate normally, and the ground source heat pump 19 supplies heat while the heat storage water tank also supplies heat as a supplement to supply heat to the indoor. The heat storage water tank stores heat through electric heating during the valley electricity period at night. The seventh operation mode is that the buried pipe 17 is directly connected to the indoor of the heat user 29. In the refrigeration season, the soil cold quantity can be directly utilized to realize free refrigeration, and the cold quantity accumulated in the soil source in winter can be released. In the first operation mode, the soil is supplemented by the heat storage water tank 18. The heat storage water tank 18 stores heat during the valley electricity period and then inputs the heat to the buried pipe 17, so as to supplement the soil temperature and meet the economic demand.

[0041] In the embodiment, the specific structure and working principle of the air source heat pump 21, the ground source heat pump 19, the heat storage water tank 18 and the heat exchanger are prior art, which will not be described here.

[0042] The multi-energy complementary heating system and method based on an air source heat pump, a ground source heat pump and a heat storage water tank has the following advantages: (1) Renewable energy such as geothermal energy and air energy is used as the dominant energy source to replace traditional high-pollution gas boilers and reduce fossil energy consumption and carbon emissions.

[0043] (2) The system has 7 switchable energy connection forms, according to the month and outdoor temperature changes throughout the year, the most efficient system operation strategy and the corresponding connection form are determined. Ensure that the system is always in an efficient operation state; fully coordinated use of air source heat pump 21, ground source heat pump 19, heat storage tank 18, combined with the valley electricity policy, taking into account energy efficiency, economy and low carbon target, especially suitable for full scene.

[0044] (3) Use the characteristics of ground source heat pump 19 and air source heat pump 21, combined with the valley electricity policy, suitable for cold regions, and can reduce operating costs. Air source heat pump 21 runs efficiently in mild weather, reducing the heat extraction pressure of ground source heat pump 19, ground source heat pump 19 supplies energy in extremely cold weather, avoiding low temperature attenuation of air source heat pump 21 energy supply efficiency, heat storage tank 18 can supplement the peak heat load, suitable for cold regions.

[0045] (4) Pay great attention to geothermal recharge, avoid the problem of soil heat imbalance caused by unbalanced cold and heat load in winter and summer in cold regions, protect the soil ecology, meet the requirements of sustainable green development.

[0046] Obviously, the above disclosed embodiments of the application are only used to help explain the application. The embodiments do not describe all the details, nor limit the application to only the specific implementation. According to the content of the specification, many modifications and changes can be made. This specification selects and describes these embodiments in order to better explain the principles and practical applications of the application, so that those skilled in the art can well understand and use the application. It is not necessary and impossible to exhaust all the embodiments here.

Claims

1. A multi-energy complementary heating system based on air source heat pump, ground source heat pump, and hot water storage tank, characterized in that, include: The ground source heat pump (19), the buried pipe (17) and the hot water storage tank (18) are connected to the hot water storage tank (18) in sequence through the first valve (1), the first water pump (24), the third valve (3) and the second water pump (25). The water outlet of the buried pipe (17) is connected to the hot water storage tank (18) in sequence through the second valve (2) and the fourth valve (4). The left water outlet of the ground source heat pump (19) is connected to the water inlet of the first water pump (24), and the left water inlet of the ground source heat pump (19) is connected to the water outlet of the second valve (2). An air source heat pump (21), a fan (22), and a water-air heat exchanger (20) are connected. The left outlet of the water-air heat exchanger (20) is connected to the right inlet of the ground source heat pump (19) via the seventh valve (7) and the third water pump (26). The left inlet of the water-air heat exchanger (20) is connected to the right outlet of the ground source heat pump (19) via the eighth valve (8). The right inlet of the water-air heat exchanger (20) is connected to the air source heat pump (19) via the twelfth valve (12). The left outlet of the heat pump (21) is connected, the right outlet of the air-water heat exchanger (20) is connected to the left inlet of the air source heat pump (21) through the eleventh valve (11), and the fan (22) is connected to the air source heat pump (21); the inlet of the first water pump (24) is connected to the outlet of the third water pump (26) through the fifth valve (5), and the outlet of the second valve (2) is connected to the inlet of the eighth valve (8) through the sixth valve (6); The plate heat exchanger (23) and the heat user (29) are connected. The left outlet of the plate heat exchanger (23) is connected to the right first interface of the air source heat pump (21) via the fourth water pump (28) and the fifteenth valve (15). The left inlet of the plate heat exchanger (23) is connected to the right second interface of the air source heat pump (21) via the sixteenth valve (16). The inlet of the third water pump (26) is connected to the outlet of the fourth water pump (28) via the ninth valve (9). The right outlet of the ground source heat pump (19) is connected to the sixth valve (6). The outlet of each water outlet is connected to the left inlet of the plate heat exchanger (23) through the tenth valve (10). The inlet of the first water pump (24) is connected to the outlet of the fifteenth valve (15) through the fourteenth valve (14) and the fifth water pump (27). The outlet of the second valve (2) is connected to the inlet of the sixteenth valve (16) through the thirteenth valve (13). The outlet of the heat user (29) is connected to the right inlet of the plate heat exchanger (23), and the inlet of the heat user (29) is connected to the right outlet of the plate heat exchanger (23).

2. A multi-energy complementary heating method based on air source heat pump, ground source heat pump, and hot water storage tank, characterized in that: The multi-energy complementary heating system based on air source heat pump, ground source heat pump and hot water storage tank as described in claim 1 includes: The multi-energy complementary heating system based on air source heat pump, ground source heat pump and hot water storage tank has seven operating modes, namely the first operating mode, the second operating mode, the third operating mode, the fourth operating mode, the fifth operating mode, the sixth operating mode and the seventh operating mode; Based on the months, the whole year is divided into the transition season, the heating season, and the cooling season; Based on the outdoor ambient temperature, the heating season is divided into five stages: the first stage, the second stage, the third stage, the fourth stage, and the fifth stage. During the current transitional season, the multi-energy complementary heating system based on air source heat pumps, ground source heat pumps, and hot water storage tanks adopts the first operating mode. Currently, in the first stage, the multi-energy complementary heating system based on air source heat pumps, ground source heat pumps, and hot water storage tanks adopts the second operating mode; Currently in the second stage, the multi-energy complementary heating system based on air source heat pumps, ground source heat pumps and hot water storage tanks adopts the third operating mode; Currently in the third stage, the multi-energy complementary heating system based on air source heat pumps, ground source heat pumps and hot water storage tanks adopts the fourth operating mode; Currently in the fourth stage, the multi-energy complementary heating system based on air source heat pumps, ground source heat pumps and hot water storage tanks adopts the fifth operating mode; Currently in the fifth stage, the multi-energy complementary heating system based on air source heat pumps, ground source heat pumps and hot water storage tanks adopts the sixth operating mode; During the current cooling season, the multi-energy complementary heating system based on air source heat pumps, ground source heat pumps, and hot water storage tanks adopts the seventh operating mode.

3. The multi-energy complementary heating method based on air source heat pump, ground source heat pump and hot water storage tank according to claim 2, characterized in that: The heating season is from October to April of the following year; the transition seasons are from May to June and from September to October; the cooling season is from June to August; the first stage is when the outdoor ambient temperature is between 3 and -3℃; the second stage is when the outdoor ambient temperature is between -4 and -10℃; the third stage is when the outdoor ambient temperature is between -11 and -17℃; the fourth stage is when the outdoor ambient temperature is between -18 and -25℃; and the fifth stage is when the outdoor ambient temperature is below -25℃.

4. The multi-energy complementary heating method based on air source heat pump, ground source heat pump and hot water storage tank according to claim 2, characterized in that: When the multi-energy complementary heating system based on air source heat pump, ground source heat pump and hot water storage tank adopts the first operating mode, the first valve (1), the second valve (2), the third valve (3) and the fourth valve (4) are all open, and the other valves are all closed. The hot water storage tank (18) replenishes the soil with heat through heat exchange with the buried pipe (17).

5. The multi-energy complementary heating method based on air source heat pump, ground source heat pump and hot water storage tank according to claim 2, characterized in that: When the multi-energy complementary heating system based on air source heat pump, ground source heat pump and hot water storage tank adopts the second operating mode, the eleventh valve (11), the twelfth valve (12), the fifteenth valve (15) and the sixteenth valve (16) are all open, and the other valves are all closed. The air source heat pump (21) operates alone to provide heat to the heat user (29).

6. The multi-energy complementary heating method based on air source heat pump, ground source heat pump and hot water storage tank according to claim 2, characterized in that: When the multi-energy complementary heating system based on air source heat pump, ground source heat pump and hot water storage tank adopts the third operating mode, the first valve (1), the second valve (2), the seventh valve (7), the eighth valve (8), the eleventh valve (11), the twelfth valve (12), the fifteenth valve (15) and the sixteenth valve (16) are all open, and the other valves are all closed. The ground source heat pump (19) assists the air source heat pump (21) in operation to provide heat to the heat user (29).

7. The multi-energy complementary heating method based on air source heat pump, ground source heat pump and hot water storage tank according to claim 2, characterized in that: When the multi-energy complementary heating system based on air source heat pump, ground source heat pump and hot water storage tank adopts the fourth operating mode, the first valve (1), the second valve (2), the ninth valve (9), the tenth valve (10), the eleventh valve (11), the twelfth valve (12), the thirteenth valve (13) and the fourteenth valve (14) are all open, and the other valves are all closed. The air source heat pump (21) assists the ground source heat pump (19) in operation to provide heat to the heat user (29).

8. The multi-energy complementary heating method based on air source heat pump, ground source heat pump and hot water storage tank according to claim 2, characterized in that: When the multi-energy complementary heating system based on air source heat pump, ground source heat pump and hot water storage tank adopts the fifth operating mode, the first valve (1), the second valve (2), the ninth valve (9) and the tenth valve (10) are all open, and the other valves are all closed. The ground source heat pump (19) operates alone to provide heat to the heat user (29).

9. The multi-energy complementary heating method based on air source heat pump, ground source heat pump and hot water storage tank according to claim 2, characterized in that: When the multi-energy complementary heating system based on air source heat pump, ground source heat pump and hot water storage tank adopts the sixth operating mode, the first valve (1), the second valve (2), the third valve (3), the fourth valve (4), the ninth valve (9) and the tenth valve (10) are all open, and the other valves are all closed. The ground source heat pump (19) and the hot water storage tank (18) jointly provide heat to the heat user (29).

10. The multi-energy complementary heating method based on air source heat pump, ground source heat pump and hot water storage tank according to claim 2, characterized in that: When the multi-energy complementary heating system based on air source heat pump, ground source heat pump and hot water storage tank adopts the seventh operating mode, the first valve (1), the second valve (2), the fifth valve (5), the sixth valve (6), the ninth valve (9) and the tenth valve (10) are all open, and the other valves are all closed, and the buried pipe (17) exchanges heat with the heat user (29).

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