Self-sufficient multi-energy complementary capillary radiation heat pump and control method thereof

Abstract

The present invention provides a self-sufficient multi-energy complementary capillary radiation heat pump and a control method thereof. The radiation heat pump includes a heat pump main system, a heat storage subsystem and a two-stage jet enthalpy increase subsystem. The control method of the heat pump realizes daytime heating + heat storage or heat storage alone, and night heating. The stored hot water is converted into heating capacity in the form of active jet enthalpy increase to improve the heating effect. The present invention is a multi-energy complementary heat pump based on two-stage jet enthalpy increase technology. The first stage is conventional jet enthalpy increase, which absorbs more air energy by increasing the supercooling degree. The second stage is that the refrigerant absorbs the heat of the external heat source and converts it into heating capacity in the form of jet enthalpy difference. In order to solve the problem that low-grade heat sources are difficult to supply, a self-sufficient low-grade heat source supply device is provided. The hot water generated by the heat pump is stored in a water tank as the low-grade heat source heat of active jet enthalpy increase. The two-stage jet enthalpy increase technology based on the self-sufficient low-grade heat source realizes multi-energy complementarity and greatly improves the performance of the heat pump.

Description

Technical Field

[0001] The invention relates to the field of heat pump systems, and in particular to a self-sufficient multi-energy complementary capillary radiation heat pump and a control method thereof. Background Art

[0002] With the development of industry and the improvement of people's living standards, heating and cooling have become inseparable in production and life, and have become vital to urban living quarters, commercial buildings and the entire life of mankind. One of the main uses of energy in large cities is to provide heat and cooling for buildings. The technical development and commercialization efforts of traditional power systems mainly focus on individual equipment, such as central heating and direct-fired central air-conditioning equipment. The common problem of these equipment is the high energy consumption under a single goal, and these equipment have not achieved efficient and comprehensive utilization of energy. The equipment investment and operating costs of the absorption cooling and heating integrated system directly burning natural gas are high, and the energy utilization rate of the system is relatively low; traditional compression cooling and heating equipment is difficult to use independently in cold areas and has poor availability; and the direct use of electric boilers not only has poor energy utilization, but also high operating costs.

[0003] Chinese patent CN1470812A discloses a heat storage type air-cooled heat pump cold and hot water integrated system, which adopts a heat storage type air-cooled heat pump cold and hot water integrated air conditioning system combined with a heat storage device and a heat recovery device, and utilizes the condensation heat of the high-pressure and high-temperature gas at the compressor outlet to effectively recover the waste heat, and increases the condensation area on the basis of adding a water heater. When heating, the national off-peak electricity policy is utilized to store heat through the operation of the heat pump unit during off-peak electricity, and release heat during peak electricity; when the climate is cold, the heat storage device is used to store heat at night, and heat is supplemented to the heat pump during the day to ensure the normal heating operation of the heat pump, and overcome the disadvantage that the heat pump cannot operate effectively in cold areas. However, the temperature is lower at night in winter, and it is difficult to exchange heat from the outside. On the contrary, the indoor heating demand is greater. The solution still does not overcome the problem of low heat exchange efficiency at night in winter.

[0004] There is also a multi-energy complementary heat pump in the prior art, which mainly includes heat pump-assisted solar water heaters and solar-assisted heat pumps. However, the heat pump has high energy consumption, serious performance degradation in low-temperature environments, and cannot be used in extremely low-temperature environments. The solution is to use multi-energy complementary heat pumps, cascade heat pumps, and jet enthalpy increase technology. Multi-energy complementary heat pumps mainly include heat pump-assisted solar water heaters and solar-assisted heat pumps. Due to the dispersion and instability of solar energy, its utilization rate is low and it is difficult to supply. The system has a large number of solar heat absorbing panels, a large heat exchanger area, inconvenient installation, and high cost. Cascade heat pumps can meet the heating needs in low-temperature environments and expand the application scope of air source heat pumps, but they have low energy efficiency, complex structure, and high cost. Conventional jet enthalpy increase technology, because the injection heat of the injected refrigerant comes from the heat pump itself, the enthalpy difference in the injection process cannot be converted into heating capacity, the heat pump performance improvement is limited, and it cannot be used in extremely low temperature environments below -20°C. Summary of the invention

[0005] The purpose of the present invention is to provide a self-sufficient multi-energy complementary capillary radiation heat pump, which can increase the suction temperature of the compressor in a low-temperature environment. Another purpose of the present invention is to provide a control method for a self-sufficient multi-energy complementary capillary radiation heat pump to solve the problem that heat pumps are difficult to heat in extremely low temperature environments, so as to reduce the energy consumption of heating in winter.

[0006] A self-sufficient multi-energy complementary capillary radiation heat pump comprises a heat pump main system and a heat storage subsystem, wherein the heat pump main system comprises a compressor and a heating main circuit, and the heat storage subsystem comprises an insulated water tank, wherein a heat exchange pipe for heating medium water is arranged in the insulated water tank, wherein the liquid outlet of the compressor is connected to an oil separator through a pipeline, wherein the oil separator is respectively connected to the heating main circuit and the heat exchange pipe, wherein the air intake of the compressor is connected to a medium return circuit, wherein a return pipe and a water outlet pipe for pumping medium water are arranged on the insulated water tank, wherein the return pipe and the water outlet pipe are connected to the medium return circuit in a heat exchange manner, and wherein a main circuit solenoid valve and a heat storage side solenoid valve are respectively arranged between the oil separator and the heating main circuit and the heat exchange pipe.

[0007] In the above scheme, without affecting the operation of the main heating circuit, an additional heat storage subsystem is set up in the bypass, so that the medium water in the insulation water tank can be heated when the temperature is high during the day, and then when the temperature is low at night, the heat in the heat storage subsystem can be used to heat the medium return pipeline of the compressor's suction port to increase the compressor's suction temperature, thereby improving heat exchange efficiency and reducing energy consumption.

[0008] Preferably, the heat pump main system further comprises a four-way reversing valve and a water-side condenser, wherein the four-way reversing valve comprises a C port, an E port, an S port and a D port connected to the main circuit solenoid valve;

[0009] The C port is sequentially connected to an outdoor heat exchanger, a main electronic expansion valve, and a high-pressure liquid storage device through pipelines; the water-side condenser includes an outlet pipe and an inlet pipe; and the high-pressure liquid storage device is connected to the outlet pipe through pipelines;

[0010] The E port is connected to the inlet pipe through a pipeline;

[0011] The S port is connected to a gas-liquid separator through a pipeline, the outlet of the gas-liquid separator is connected to the suction port of the compressor through a suction pipe, and the suction pipe is connected to the oil separator through an oil return capillary tube;

[0012] During heating operation, port D is connected to port S, and port C is connected to port E.

[0013] Preferably, a primary subcooler is arranged on the pipeline between the high-pressure liquid storage device and the main electronic expansion valve, the pipeline between the main electronic expansion valve and the primary subcooler is a main liquid pipe, the primary subcooler comprises a primary liquid inlet connected to the outlet pipe, a primary liquid outlet connected to the main liquid pipe, a primary air inlet and a primary air outlet, the outlet pipe is connected to the primary air inlet through a pipeline and a primary subcooling electronic expansion valve is arranged on the pipeline, a mixing injection pipe is arranged at the air intake of the compressor, and the primary air outlet is connected to the mixing injection pipe through the primary injection pipe.

[0014] Preferably, a secondary subcooler is further included, the secondary subcooler includes a secondary liquid inlet connected to the reflux pipe, a secondary liquid outlet connected to the water outlet pipe, a secondary air inlet and a secondary air outlet, the main liquid pipe is connected to the secondary air inlet through a pipeline and a secondary subcooling electronic expansion valve is arranged on the pipeline, a mixing injection pipe is arranged at the air intake of the compressor, and the secondary air outlet is connected to the mixing injection pipe through the secondary injection pipe.

[0015] Preferably, the liquid outlet section of the heat exchange tube is connected to the D port or the main liquid pipe, and a one-way valve is provided on the liquid outlet section of the heat exchange tube.

[0016] Preferably, an exhaust temperature sensor and a high-pressure pressure sensor are arranged on the pipeline between the compressor and the oil separator, a water temperature sensor is arranged in the insulated water tank, a heat storage side water pump and a return water temperature sensor are arranged on the return pipe, an outdoor temperature sensor for detecting the ambient temperature of the outdoor unit and a coil temperature sensor for detecting the temperature of the heat exchange tube on the outdoor heat exchanger are arranged at the outdoor heat exchanger, a water inlet and a water outlet are arranged on the water side condenser, a water side water pump and an inlet water temperature sensor are arranged on the water inlet, and an outlet water temperature sensor is arranged on the water outlet, an injection refrigerant inlet temperature sensor is arranged on the pipeline between the secondary subcooling electronic expansion valve and the secondary air inlet, an injection refrigerant outlet temperature sensor is arranged on the secondary injection pipe, and an intake temperature sensor and a low-pressure switch are arranged between the S port and the gas-liquid separator.

[0017] A control method for a self-sufficient multi-energy complementary capillary radiation heat pump comprises the following steps:

[0018] S1. Obtain the time t indicated by the local clock in real time and obtain the water temperature T through the water temperature sensor in real time tank , the inlet water temperature T is obtained in real time through the inlet water temperature sensor w.in , preset target water temperature T tank.set , water temperature deviation value T x =2~4℃, temperature return value T y =1~2℃, high water temperature threshold T z =38~42℃, target water inlet temperature T w.set ;

[0019] S2, when the heat pump stops heating and receives the heat storage instruction and T tank <T tank.set -T x When 10:00≤t≤15:00 and the compressor is stopped for more than 3 minutes, the solenoid valve on the heat storage side opens, the main electronic expansion valve opens, and single heat storage operation is performed;

[0020] When the heating command is received and T w.in <T w.set When the temperature is -2℃ and the compressor is stopped for more than 3 minutes, the main solenoid valve opens, the main electronic expansion valve opens, and the heating operation begins;

[0021] When the heating command is received and T tank <T tank.set -T y When the compressor stops for more than 3 minutes and 10:00≤t≤15:00, the main circuit solenoid valve and the heat storage side solenoid valve are opened, the main electronic expansion valve is opened, and the heat storage operation is started;

[0022] S3, when T tank >T tak.set +T x , the solenoid valve on the heat storage side is closed, and the single heat storage operation stops;

[0023] When T w.in >T w.set +T y When the main solenoid valve is closed, the heating operation stops;

[0024] When T tank >T tank.set +T y Or when 0:00≤t<10:00 or 15:00<t<24:00, the heat storage operation stops.

[0025] In the above solution, by heating and heat storage in different time periods, the problem that it is difficult to generate heat in the application of heat pumps in extremely low temperature environments is solved, so as to reduce the energy consumption of heating in winter.

[0026] Preferably, during the heating operation, the system makes a judgment. When 0:00 ≤ t < 10:00 or 15:00 < t < 24:00, and Ttank > Tz, it enters the heat release control. The heat release control includes the following steps:

[0027] A1. The refrigerant inlet temperature T is obtained by real-time collection through the refrigerant inlet temperature sensor inj.in , and T is obtained by real-time collection through the return water temperature sensor ex.out . The preset target temperature difference value T r.w = 5 - 8 °C and the minimum temperature difference value T r.w.set = 2 - 4 °C;

[0028] A2. The heat storage side water pump starts to operate, and the secondary subcooling electronic expansion valve opens. Control the opening of the secondary subcooling electronic expansion valve so that T ex.out - T inj.in = T r.w or the secondary subcooling electronic expansion valve reaches the maximum opening;

[0029] A3. When T ex.out - T inj.in < T r.w.set or 10:00 ≤ t ≤ 15:00, the secondary subcooling electronic expansion valve closes, and the heat storage side water pump stops rotating.

[0030] Preferably, during the single heat storage operation, when Ttank.set - Tx < Ttank < Ttank.set + Tx, the compressor maintains the current operating frequency. When T tank < T tank.set , the compressor increases the frequency. When T tank > T tank.set + T x , the compressor stops, and the outdoor heat exchanger stops;

[0031] During the heating operation, when T w.set - T y < T w.in ≤ T w.set , the compressor maintains the current operating frequency; when T w.set < T w.in ≤ T w.set + T x , the compressor reduces the frequency at a speed of 1 - 2 Hz / min until the minimum operating frequency = 15 - 20 Hz; when T w.in > T w.set + 1 °C, stop heating;

[0032] During the heat storage operation, when the heat exchange tube heats the medium water, it enters the D port or the main liquid pipe.

[0033] The present invention is a multi-energy complementary heat pump based on two-stage jet enthalpy increase technology. The first stage is conventional jet enthalpy increase, which absorbs more air energy by increasing the degree of supercooling. The second stage is that the refrigerant absorbs the heat of the external heat source and converts it into heating capacity in the form of jet enthalpy difference. In order to solve the problem that low-grade heat sources are difficult to supply, a self-sufficient low-grade heat source supply device is provided. The hot water generated by the heat pump is stored in the water tank as the low-grade heat source heat of active jet enthalpy increase. The two-stage jet enthalpy increase technology based on the self-sufficient low-grade heat source realizes multi-energy complementarity and greatly improves the performance of the heat pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of a parallel self-sufficient multi-energy complementary heat pump system;

[0035] Figure 2 It is a structural schematic diagram of a heat storage bypass type self-sufficient multi-energy complementary heat pump system;

[0036] Figure 3 This is the refrigerant flow diagram of the parallel self-contained multi-energy complementary heat pump system during conventional heating operation;

[0037] Figure 4 This is the refrigerant flow diagram for the conventional heating operation of the heat storage bypass self-contained multi-energy complementary heat pump system;

[0038] Figure 5 This is the refrigerant flow diagram when the single-open independent heat storage operation;

[0039] Figure 6 , 7 The refrigerant flow diagram of the heat storage process of the two schemes of the present invention;

[0040] Figure 8 , 9 The schematic diagram of the heat release and heating process of the two schemes of the present invention;

[0041] Fig.10 This is the principle diagram of the two-stage jet enthalpy-increasing heat pump system;

[0042] Fig.11 It is the pressure-enthalpy diagram of the two-stage jet enthalpy-increasing heat pump system;

[0043] 10. Heat storage subsystem; 11. Insulated water tank; 12. Return pipe; 13. Outlet pipe; 14. Solenoid valve on heat storage side; 15. Check valve; 16. Water temperature sensor; 17. Heat exchange pipe; 18. Water pump on heat storage side; 19. Return water temperature sensor; 20. Compressor; 21. Exhaust temperature sensor; 22. High pressure sensor; 30. Oil separator; 40. Main solenoid valve; 50. Four-way reversing valve; 51. C port; 52. E port; 53. S port; 54. D port; 60. Water side condenser; 61. Outlet pipe; 62. Inlet pipe; 63. Inlet water temperature sensor; 64. Outlet water temperature sensor; 65. Water side pump; 71. Outdoor heat exchanger; 711. Outdoor temperature sensor; 712. Coil temperature sensor; 7 2. Main electronic expansion valve; 73. High-pressure liquid storage tank; 74. Gas-liquid separator; 741. Intake temperature sensor; 742. Low-pressure switch; 75. Oil return capillary; 76. Intake pipe; 77. Main liquid pipe; 78. Mixing injection pipe; 80. Primary subcooler; 81. Primary liquid inlet; 82. Primary liquid outlet; 83. Primary air inlet; 84. Primary air outlet; 85. Primary subcooling electronic expansion valve; 86. Primary injection pipe; 90. Secondary subcooler; 91. Secondary liquid inlet; 92. Secondary liquid outlet; 93. Secondary air inlet; 94. Secondary air outlet; 95. Secondary subcooling electronic expansion valve; 96. Secondary injection pipe; 97. Injection refrigerant outlet temperature sensor; 98. Injection refrigerant inlet temperature sensor. DETAILED DESCRIPTION

[0044] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0045] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by terms such as "bottom", "outside", and "front and back" are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0046] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] A self-sufficient multi-energy complementary capillary radiation heat pump comprises a heat pump main system and a heat storage subsystem 10, wherein the heat pump main system comprises a compressor 20 and a main heating circuit, and the heat storage subsystem 10 comprises an insulated water tank 11, wherein a heat exchange pipe 17 for heating medium water is arranged in the insulated water tank 11, and an oil separator 30 is connected to the liquid outlet of the compressor 20 through a pipeline, and the oil separator 30 is respectively connected to the main heating circuit and the heat exchange pipe 17, and an air intake of the compressor 20 is connected to a medium return circuit, and a return pipe 12 and a water outlet pipe 13 for pumping medium water are arranged on the insulated water tank 11, and the return pipe 12 and the water outlet pipe 13 form a heat exchange connection with the medium return circuit, and a main circuit solenoid valve 40 and a heat storage side solenoid valve 14 are respectively arranged between the oil separator 30 and the main heating circuit and the heat exchange pipe 17.

[0048] In the above scheme, considering the dispersion and instability of low-grade heat sources, the utilization efficiency is low, the heat storage device is large, the space is large, the installation is limited, and the factory waste heat is transported over long distances, and the cost is high. These defects seriously hinder the use of low-grade heat sources in heat pumps. The present application designs a self-sufficient low-grade heat source supply device in the heat pump unit, and the hot water generated by the heat pump is stored in the insulated water tank 11 as the low-grade heat source heat for active jet enthalpy increase. The heat of the hot water includes the low-grade heat source heat of the tap water itself, the heat generated by the compressor, and the absorbed air energy as the low-grade heat source heat. Without affecting the operation of the main heating circuit, an additional bypass is set up to store a heat storage subsystem 10, so that the medium water in the insulated water tank 11 can be heated when the temperature is high during the day, and then the heat in the heat storage subsystem 10 can be used to heat the medium return pipeline of the suction port of the compressor 20 when the temperature is low at night to increase the suction temperature of the compressor 20, thereby improving the heat exchange efficiency and reducing energy consumption.

[0049] Preferably, the heat pump main system further includes a four-way reversing valve 50 and a water-side condenser 60, wherein the four-way reversing valve 50 includes a C port 51, an E port 52, an S port 53, and a D port 54 connected to the main circuit solenoid valve 40;

[0050] The C port 51 is sequentially connected to an outdoor heat exchanger 71, a main electronic expansion valve 72, and a high-pressure liquid storage 73 through pipelines. The water-side condenser 60 includes an outlet pipe 61 and an inlet pipe 62. The high-pressure liquid storage 73 is connected to the outlet pipe 61 through a pipeline.

[0051] The E port 52 is connected to the inlet pipe 62 through a pipeline;

[0052] The S port 53 is connected to a gas-liquid separator 74 through a pipeline, the outlet of the gas-liquid separator 74 is connected to the suction port of the compressor 20 through a suction pipe 76, and the suction pipe 76 is connected to the oil separator 30 through an oil return capillary 75;

[0053] During the heating operation, the D port 54 is connected to the S port 53 , and the C port 51 is connected to the E port 52 .

[0054] During heating operation, the compressor 20 discharges high-temperature gaseous refrigerant, passes through the oil separator 30 and the main electromagnetic valve 40, enters the four-way reversing valve 50, and then enters the water-side condenser 60. The water-side water pump 65 operates, and the high-temperature gaseous refrigerant and water exchange heat in the water-side condenser 60. The refrigerant that releases heat enters the primary subcooler 80, passes through the main liquid pipe 77 and the high-pressure liquid storage 73, enters the main electronic expansion valve 72 for throttling, and the throttled refrigerant enters the outdoor heat exchanger 71 to exchange heat with the outdoor air and absorb the energy of the outdoor air. The refrigerant that absorbs heat passes through the four-way reversing valve 50 and the gas-liquid separator 74 and returns to the compressor to complete the heating cycle.

[0055] Preferably, a primary subcooler 80 is arranged on the pipeline between the high-pressure liquid storage tank 73 and the main electronic expansion valve 72, and the pipeline between the main electronic expansion valve 72 and the primary subcooler 80 is a main liquid pipe 77. The primary subcooler 80 includes a primary liquid inlet 81 connected to the outlet pipe 61, a primary liquid outlet 82 connected to the main liquid pipe 77, a primary air inlet 83 and a primary air outlet 84. The outlet pipe 61 is connected to the primary air inlet 83 through a pipeline and a primary subcooling electronic expansion valve 85 is arranged on the pipeline. A mixing injection pipe 78 is arranged at the air intake of the compressor 20, and the primary air outlet 84 is connected to the mixing injection pipe 78 through a primary injection pipe 86. The first-stage subcooler 80 is used for conventional jet enthalpy increase. At this time, the first-stage subcooling electronic expansion valve 85 is opened to adjust its opening degree, and the second-stage subcooling electronic expansion valve 95 is closed. The refrigerant flowing out of the water side condenser 60, a part of which enters the first-stage subcooling electronic expansion valve 85 after throttling, enters the first-stage subcooler 80, and exchanges heat with the refrigerant in the mainstream path in the first-stage subcooler 80. After the heat exchange, this part of the refrigerant enters the first-stage injection pipe 86 and the mixing injection pipe 78, and is injected into the intermediate pressure chamber of the compressor.

[0056] Preferably, a secondary subcooler 90 is further included, and the secondary subcooler 90 includes a secondary liquid inlet 91 connected to the reflux pipe 12, a secondary liquid outlet 92 connected to the water outlet pipe 13, a secondary air inlet 93 and a secondary air outlet 94, the main liquid pipe 77 is connected to the secondary air inlet 93 through a pipeline and a secondary subcooling electronic expansion valve 95 is arranged on the pipeline, a mixing injection pipe 78 is arranged at the air intake of the compressor 20, and the secondary air outlet 94 is connected to the mixing injection pipe 78 through a secondary injection pipe 96.

[0057] When the heating mode is running, the high-temperature gaseous refrigerant discharged by the compressor enters the condenser and exchanges heat with water. After condensing and releasing heat in the main water-side heat exchanger, part of the refrigerant flows through the main route: passing through the subcooler, main electronic expansion valve, evaporator, and four-way reversing valve, and returns to the variable frequency compressor. After condensing and releasing heat, part of the refrigerant enters the internal heat source injection auxiliary route, passes through the internal heat source injection electronic expansion valve for throttling, enters the subcooler for heat exchange with the main route refrigerant. Another part of the refrigerant enters the external heat source injection auxiliary route, passes through the external heat source injection electronic expansion valve for throttling, enters the external heat source economizer for heat exchange with the external heat source, and after absorbing heat, merges with the refrigerant in the internal heat source injection auxiliary route and is injected into the intermediate pressure chamber of the DC variable frequency compressor.

[0058] The corresponding pressure-enthalpy diagram is Fig.11 In the figure, j and J fall in the superheated zone and the two-phase zone respectively. The corresponding injection refrigerant states are superheated gas and gas-liquid two-phase, and the injection modes are gas injection and two-phase injection. In the figure, K represents the injection state (gas injection or liquid injection).

[0059] According to the heat pump cycle theory, for conventional injection, the heat pump heating capacity is Q h，K It can be expressed as

[0060] Q h，K =Q e，K +EP K

[0061] Where: Q e，K , E.P. K are the air energy absorbed by the evaporator and the compression work respectively. e，K The calculation expression is

[0062] Q e，K =m K ×(h 1，K -h 4，K )

[0063] Compression work EP K is the sum of the two-stage compression work, expressed as

[0064]

[0065] Obviously, the injection enthalpy difference is not included in the heating capacity, so conventional refrigerant injection has limited effect on increasing the heating capacity. For a dual-source heat pump with dual refrigerant injection, the heating capacity of the heat pump can be expressed as

[0066] Q h，K =Q e，K +Q inj，K +EP K

[0067] Where: Q inj，K is the injection enthalpy difference, calculated as

[0068] Q inj，K =m i，K2 ×(h K，9B -h K，8 )

[0069] Energy efficiency ratio COP K The calculation formula is

[0070]

[0071] Where: Q h，0 .Q ex They are the heating capacity without injection and the external heating capacity.

[0072] The above theoretical analysis shows that: designing a two-stage jet enthalpy increase, the subcooling degree is increased in each stage (the temperature difference between the saturation temperature corresponding to the exhaust pressure of the compressor 20 and the main liquid pipe 77), and the evaporator absorbs more air energy; the two-stage jet enthalpy increase, the jet refrigerant absorbs the heat of the external heat source in the secondary subcooler 90, and is injected into the intermediate pressure chamber of the compressor 20, and two-stage compression is performed. The injection process will increase the compression work and generate thermal work gain. The injection enthalpy difference and thermal work gain are very beneficial to the heat pump heating at extremely low ambient temperatures, and can solve the technical bottleneck that the heat pump cannot be used under this working condition. Hot water is transported to the secondary subcooler 90 by a water pump, and exchanges heat with the injected refrigerant. The refrigerant that absorbs heat is injected into the intermediate pressure chamber of the compressor, realizing active jet enthalpy increase, converting the injection enthalpy difference into heating, and realizing thermal work gain, which greatly improves the performance of the heat pump.

[0073] Preferably, the liquid outlet section of the heat exchange tube 17 is connected to the D port 54 or the main liquid pipe 77, and a one-way valve 15 is provided on the liquid outlet section of the heat exchange tube 17. Figure 1 As shown, the liquid outlet section of the heat exchange tube 17 is connected to the D port 54 to form a heat storage bypass type self-sufficient multi-energy complementary self-sufficient multi-energy complementary capillary radiation heat pump, and its heat storage process is as follows:

[0074] The high-temperature gaseous refrigerant exhausted by the compressor 20 passes through the oil separator 30 and the heat storage side solenoid valve 14, enters the heat preservation water tank 11, and exchanges heat with the water in the water tank. The refrigerant after releasing heat passes through the one-way valve 15, enters the main liquid pipe 77, flows through the high-pressure liquid storage tank 73, passes through the main electronic expansion valve 72, enters the outdoor heat exchanger 71 after throttling, enters the four-way reversing valve 50, flows into the gas-liquid separator 74, and then returns to the compressor 20. During the heat storage process, in order to absorb more air energy, conventional jet enthalpy increase is performed, and the first-stage subcooling electronic expansion valve 85 is opened and adjusted, and the process is the same as conventional jet enthalpy increase.

[0075] like Figure 2As shown, the liquid outlet section of the heat exchange tube 17 is connected to the main liquid pipe 77 to form a heat storage parallel type self-sufficient multi-energy complementary self-sufficient multi-energy complementary capillary radiation heat pump;

[0076] After the high-temperature gaseous refrigerant exhausted from the compressor 20 passes through the oil separator 30, a portion of the refrigerant passes through the heat storage side solenoid valve 14 and enters the thermal insulation water tank 11. The thermal insulation water tank 11 is a pressure-bearing thermal insulation water tank filled with water. The water in the water tank absorbs the heat of the refrigerant and stores the heat. Another portion of the heat passes through the main circuit solenoid valve 40, and after mixing, the conventional heat pump operation is performed.

[0077] Preferably, an exhaust temperature sensor 21 and a high-pressure pressure sensor 22 are provided on the pipeline between the compressor 20 and the oil separator 30, a water temperature sensor 16 is provided in the insulated water tank 11, a heat storage side water pump 18 and a return water temperature sensor 19 are provided on the return pipe 12, an outdoor temperature sensor 711 for detecting the ambient temperature of the outdoor unit and a coil temperature sensor 712 for detecting the temperature of the heat exchange tube 17 on the outdoor heat exchanger 71 are provided at the outdoor heat exchanger 71, and the water side condenser A water inlet and a water outlet are provided on 60, the water inlet is provided with a water side water pump 65 and a water inlet temperature sensor 63, the water outlet is provided with a water outlet temperature sensor 64, an injection refrigerant inlet temperature sensor 98 is provided on the pipeline between the secondary subcooling electronic expansion valve 95 and the secondary air inlet 93, an injection refrigerant outlet temperature sensor 97 is provided on the secondary injection pipe 96, and an intake temperature sensor 741 and a low pressure switch 742 are provided between the S port 53 and the gas-liquid separator 74.

[0078] A control method for a self-sufficient multi-energy complementary capillary radiation heat pump comprises the following steps:

[0079] S1, real-time acquisition of the local clock indicated time t, and real-time acquisition of the water temperature T by the water temperature sensor 16 tank The inlet water temperature T is obtained by real-time acquisition through the inlet water temperature sensor 63. w.in , preset target water temperature T tank.set , water temperature deviation value T x =2~4℃, temperature return value T y =1~2℃, high water temperature threshold T z =38~42℃, target water inlet temperature T w.set ;

[0080] S2, when the heat pump stops heating and receives the heat storage instruction and T tank <T tank.set -T x When 10:00≤t≤15:00 and the compressor 20 is stopped for more than 3 minutes, the heat storage side solenoid valve 14 is opened, the main electronic expansion valve 72 is opened, and single heat storage operation is performed;

[0081] When a heating start command is received and T w.in <T w.set < -2°C and the compressor 20 has been stopped for more than 3 minutes, the main circuit solenoid valve 40 is opened, the main electronic expansion valve 72 is opened, and the heating operation is entered;

[0082] When a heating start command is received and T tank <T tank.set -T y and the compressor 20 has been stopped for more than 3 minutes and 10:00 ≤ t ≤ 15:00, the main circuit solenoid valve 40 and the heat storage side solenoid valve 14 are opened, the main electronic expansion valve 72 is opened, and the heat storage operation is entered;

[0083] S3. When T tank >T tank.set +T x , the heat storage side solenoid valve 14 is closed, and the single heat storage operation stops;

[0084] When T w.in >T w.set +T y , the main circuit solenoid valve 40 is closed, and the heating operation stops;

[0085] When T tank >T tank.set +T y or 0:00 ≤ t < 10:00 or 15:00 < t < 24:00, the heat storage operation stops.

[0086] Preferably, during the heating operation, the system makes a determination. When 0:00 ≤ t < 10:00 or 15:00 < t < 24:00 and Ttank > Tz, the heat release control is entered. The heat release control includes the following steps:

[0087] A1. The refrigerant inlet temperature T inj.in is obtained by real-time acquisition through the refrigerant inlet temperature sensor 98, and T ex.out is obtained by real-time acquisition through the return water temperature sensor 19. The preset target temperature difference value T r.w = 5 - 8°C and the minimum temperature difference value T r.w.set = 2 - 4°C;

[0088] A2. The heat storage side water pump 18 is started and operated, the secondary subcooling electronic expansion valve 95 is opened, and the opening degree of the secondary subcooling electronic expansion valve 95 is controlled so that T ex.out -T inj.in = T r.w or the secondary subcooling electronic expansion valve 95 reaches the maximum opening degree;

[0089] A3. When T ex.out -T inj.in <Tr.w.set At t or 10:00≤t≤15:00, the secondary subcooling electronic expansion valve 95 is closed and the heat storage side water pump 18 stops.

[0090] The exothermic process is as follows:

[0091] When the temperature of the hot water in the insulated water tank 11 reaches the target temperature, such as 55°C, the solenoid valve 14 on the heat storage side is closed, the water pump 18 on the heat storage side is turned on, and the secondary subcooling electronic expansion valve 95 is turned on to adjust the opening of the electronic expansion valve. Under the action of the water pump, the hot water enters the secondary subcooler 90. Part of the refrigerant in the main liquid pipe 77 passes through the secondary subcooling electronic expansion valve 95 and enters the secondary subcooler 90. The hot water and the injected refrigerant exchange heat in the secondary subcooler 90. After absorbing the heat, the refrigerant is mixed with the first-stage injected refrigerant and then injected into the intermediate pressure chamber of the compressor through the secondary injection pipe 96. The heat pump heating process is the same as the heating process of a conventional heat pump. Conventional jet enthalpy increase process Conventional heat pump jet enthalpy increase.

[0092] As a preferred method, during the single heat storage operation, when T tank.set -T x <T tank <T tank.set +T x When T tank <T tank.set When T tank >T tank.set +T x When , the compressor 20 stops, and the outdoor heat exchanger 71 stops;

[0093] During the heating operation, when T w.set -T y <T w.in ≤T w.set When T w.set <T w.in ≤T w.set +T x When T w.in >T w.set +1℃, stop heating;

[0094] During the heat storage operation, after the heat exchange tube 17 heats the medium water, it enters the D port 54 or the main liquid pipe 77 .

[0095] The suction temperature sensor collects the compressor suction temperature Ts in real time, and the coil temperature sensor 712 collects the coil temperature T in real time. def , define suction superheat ΔT s =Ts -T def ;

[0096] During the single heat storage operation, the main electronic expansion valve 72 is opened to the initial opening for 3-4 minutes, and the initial opening is 100-150 steps, and then the suction superheat ΔT s The opening is adjusted according to the target, and the superheat target is generally 1-2℃.

[0097] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A self-sufficient multi-energy complementary capillary radiation heat pump, characterized in that: The invention comprises a heat pump main system and a heat storage subsystem (10), wherein the heat pump main system comprises a compressor (20) and a main heating circuit, and the heat storage subsystem (10) comprises a heat-insulating water tank (11), wherein a heat exchange pipe (17) for heating medium water is arranged in the heat-insulating water tank (11), wherein the liquid outlet of the compressor (20) is connected to an oil separator (30) via a pipeline, wherein the oil separator (30) is respectively connected to the main heating circuit and the heat exchange pipe (17), wherein the air intake of the compressor (20) is connected to a medium return pipeline, wherein a return pipe (12) and a water outlet pipe (13) for pumping medium water are arranged on the heat-insulating water tank (11), wherein the return pipe (12) and the water outlet pipe (13) are connected to the medium return pipeline in a heat-exchange manner, and a main circuit electromagnetic valve (40) and a heat storage side electromagnetic valve (14) are respectively arranged between the oil separator (30) and the main heating circuit and the heat exchange pipe (17); The heat pump main system further comprises a four-way reversing valve (50) and a water-side condenser (60); the four-way reversing valve (50) comprises a C port (51), an E port (52), an S port (53), and a D port (54) which is in communication with the main electromagnetic valve (40); the C port (51) is sequentially connected to an outdoor heat exchanger (71), a main electronic expansion valve (72), and a high-pressure liquid storage device (73) via pipelines; the water-side condenser (60) comprises an outlet pipe (61) and an inlet pipe (62); the high-pressure liquid storage device (73) ) is connected to the outlet pipe (61) through a pipeline; the E port (52) is connected to the inlet pipe (62) through a pipeline; the S port (53) is connected to the gas-liquid separator (74) through a pipeline, the outlet of the gas-liquid separator (74) is connected to the suction port of the compressor (20) through an intake pipe (76), and the intake pipe (76) is connected to the oil separator (30) through an oil return capillary (75); during heating operation, the D port (54) is connected to the S port (53), and the C port (51) is connected to the E port (52); A primary subcooler (80) is provided on the pipeline between the high-pressure liquid storage device (73) and the main electronic expansion valve (72); the pipeline between the main electronic expansion valve (72) and the primary subcooler (80) is a main liquid pipe (77); the primary subcooler (80) comprises a primary liquid inlet (81) connected to the outlet pipe (61), a primary liquid outlet (82) connected to the main liquid pipe (77), a primary air inlet (83) and a primary air outlet (84); the outlet pipe (61) is connected to the primary air inlet (83) through a pipeline and a primary subcooling electronic expansion valve (85) is provided on the pipeline; a mixing injection pipe (78) is provided at the air intake of the compressor (20); and the primary air outlet (84) is connected to the mixing injection pipe (78) through a primary injection pipe (86); The compressor (20) further comprises a secondary subcooler (90), the secondary subcooler (90) comprising a secondary liquid inlet (91) connected to the reflux pipe (12), a secondary liquid outlet (92) connected to the water outlet pipe (13), a secondary air inlet (93) and a secondary air outlet (94); the main liquid pipe (77) is connected to the secondary air inlet (93) via a pipeline and a secondary subcooling electronic expansion valve (95) is provided on the pipeline; a mixing injection pipe (78) is provided at the air intake of the compressor (20); and the secondary air outlet (94) is connected to the mixing injection pipe (78) via a secondary injection pipe (96).

2. The self-sufficient multi-energy complementary capillary radiation heat pump according to claim 1 is characterized in that: The liquid outlet section of the heat exchange tube (17) is in communication with the D port (54) or the main liquid pipe (77), and a one-way valve (15) is provided on the liquid outlet section of the heat exchange tube (17).

3. The self-sufficient multi-energy complementary capillary radiation heat pump according to claim 2 is characterized in that: An exhaust temperature sensor (21) and a high-pressure pressure sensor (22) are provided on the pipeline between the compressor (20) and the oil separator (30); a water temperature sensor (16) is provided in the thermal insulation water tank (11); a heat storage side water pump (18) and a return water temperature sensor (19) are provided on the return pipe (12); an outdoor temperature sensor (711) for detecting the ambient temperature of the outdoor unit and a coil temperature sensor (712) for detecting the temperature of the heat exchange tube (17) on the outdoor heat exchanger (71) are provided at the outdoor heat exchanger (71); and the water side condenser (6 0) is provided with a water inlet and a water outlet, the water inlet is provided with a water side water pump (65) and a water inlet temperature sensor (63), the water outlet is provided with a water outlet temperature sensor (64), the pipeline between the secondary subcooling electronic expansion valve (95) and the secondary air inlet (93) is provided with an injection refrigerant inlet temperature sensor (98), the secondary injection pipe (96) is provided with an injection refrigerant outlet temperature sensor (97), and an intake temperature sensor (741) and a low pressure switch (742) are provided between the S port (53) and the gas-liquid separator (74).

4. A control method for a self-sufficient multi-energy complementary capillary radiation heat pump as claimed in any one of claims 1 to 3, characterized in that: The steps include: S1, real-time acquisition of the local clock indicated time t, and real-time acquisition of the water temperature T by the water temperature sensor (16) tank The inlet water temperature T is obtained in real time by collecting the inlet water temperature sensor (63). w.in , preset target water temperature T tank.set , water temperature deviation value T x =2~4℃, temperature return value T y =1~2℃, high temperature threshold T z =38~42℃, target water inlet temperature T w.set ; S2, when the heat pump stops heating and receives the heat storage instruction and T tank <T tank.set -T x When 10:00≤t≤15:00 and the compressor (20) is stopped for more than 3 minutes, the heat storage side solenoid valve (14) is opened, the main electronic expansion valve (72) is opened, and single heat storage operation is performed; When the heating command is received and T w.in <T w.set When the temperature is -2°C and the compressor (20) is stopped for more than 3 minutes, the main solenoid valve (40) opens, the main electronic expansion valve (72) opens, and the heating operation begins; When the heating command is received and T tank <T tank.set -T y When the compressor (20) is stopped for more than 3 minutes and 10:00≤t≤15:00, the main circuit solenoid valve (40) and the heat storage side solenoid valve (14) are opened, and the main electronic expansion valve (72) is opened, and the heat storage operation is entered; S3, when T tank >T tank.set +T x , the solenoid valve (14) on the heat storage side is closed, and the single heat storage operation stops; When T w.in >T w.set +T y When the main electromagnetic valve (40) is closed, the heating operation stops; When T tank >T tank . set +T y Or when 0:00≤t<10:00 or 15:00<t<24:00, the heat storage operation stops.

5. The control method of the self-sufficient multi-energy complementary capillary radiation heat pump according to claim 4 is characterized in that: The heating operation time system makes a judgment, when 0:00≤t<10:00 or 15:00<t<24:00, and T tank＞ T z When the heat release control is started, the heat release control includes the following steps: A1. The refrigerant inlet temperature T is obtained by injecting a refrigerant inlet temperature sensor (98) in real time. inj.in , and the return water temperature sensor (19) collects the real-time data T ex.out , preset target temperature difference value T r.w =5~8℃ and minimum temperature difference T r.w.set =2~4℃; A2. The water pump (18) on the heat storage side is started and the secondary subcooling electronic expansion valve (95) is opened. The opening degree of the secondary subcooling electronic expansion valve (95) is controlled so that T ex.out -T inj.in =T r.w or the secondary subcooling electronic expansion valve (95) reaches the maximum opening; A3. When T ex.out -T inj.in <T r.w.set At t ≤ t ≤ 15:00 or 10:00 ≤ t ≤ 15:00, the secondary subcooling electronic expansion valve (95) is closed and the heat storage side water pump (18) is stopped.

6. The control method of the self-sufficient multi-energy complementary capillary radiation heat pump according to claim 5 is characterized in that: During the single heat storage operation, the compressor (20) starts. tank.set -T x <T tank <T tank.set +T x When T tank < T tank.set When T tank >T tank.set +T x When the compressor (20) is shut down, the outdoor heat exchanger (71) is shut down; During the heating operation, when T w.set -T y <T w.in ≤T w.set When T w.set <T w.in ≤T w.set +T x When T w.in >T w.set +1℃, stop heating; During the heat storage operation, after the heat exchange tube (17) has heated the medium water, the medium water enters the D port (54) or the main liquid pipe (77).

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