Heat pump and phase change heat storage and cold storage coupled cold and heat combined supply system and control method thereof

Abstract

The invention provides a heat pump and phase change heat storage and cold storage coupled cold and heat combined supply system and a control method thereof. The heat pump and phase change heat storage and cold storage coupled cold and heat combined supply system comprises a two-stage compression heat pump or cascade heat pump, a phase change cold storage device, a phase change heat storage device, a waste heat source, an air cooler, a fourth heat exchanger and a fifth heat exchanger. The first heat exchanger, the first compressor, the second compressor, the third heat exchanger and the first expansion valve sequentially communicate to form a first circulation pipeline. The first heat exchanger, the phase change cold storage device and the fourth heat exchanger are sequentially communicated to form a second circulating pipeline; the third heat exchanger, the phase change heat storage device and the fifth heat exchanger are sequentially communicated to form a third circulating pipeline; the fourth heat exchanger and the waste heat source are sequentially communicated to form a fourth circulating pipeline; and the fifth heat exchanger and the air cooler are sequentially communicated to form a fifth circulating pipeline. The two ends of the two-stage compression type heat pump or the cascade type heat pump are coupled with the phase change cold and heat storage device, large-temperature-difference refrigeration and heat supply are achieved at the same time, the energy use efficiency is improved, and the double requirements for cold and heat of a user are met.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigeration and heating for industrial or commercial buildings. Specifically, it relates to a combined cooling and heating supply system coupling a large temperature difference heat pump with phase change heat storage and cold storage and its control method. Background Art

[0003] A heat pump is a device that uses high-level energy to make heat flow from a low level to a high level. Through a heat pump cycle, the heat absorbed by the evaporator is upgraded in grade, and heat is released to the heat sink through the condenser. Multistage compression heat pumps can improve the cooling and heating supply capacity of heat pumps under large temperature differences, and are divided into dual / multistage compression cycles and cascade cycles. The dual / multistage compression heat pump first compresses the low-pressure steam from the evaporator to a certain intermediate pressure by a low-pressure stage compressor, and then compresses it to the condensation pressure by a high-pressure stage compressor, which not only meets the requirements of the evaporation temperature and condensation temperature of the heat pump system, but also keeps the compression ratio of the compressor within a reasonable range. The cascade heat pump consists of a high-temperature stage and a low-temperature stage, and the two parts form independent circulation systems. First, the low-temperature stage is used to initially raise the temperature, and then the high-temperature stage is used to produce the required temperature. The evaporative condenser is the connecting device between the low-temperature stage and the high-temperature stage. Limited by the mismatch in the time and quantity of cooling and heating supply and demand, a single device usually cannot meet the cooling and heating needs of users simultaneously. Heat storage can solve the problems brought by the mismatch between the supply and demand of thermal energy in terms of time, space or intensity, and maximize the energy utilization rate of the entire system.

[0004] The existing Chinese patent with the publication number CN115200119A discloses an air-conditioning water system using a water source heat pump for cooling and heating and high-low zoning, including high-zone air-conditioning users, high-zone air-conditioning circulation pumps, low-zone air-conditioning users, low-zone air-conditioning circulation pumps, a water source primary-side circulation pump, a water source secondary-side circulation pump, a water source heat pump unit, and a primary cold and heat source. The primary cold source and the primary heat source are both arranged in the high zone or both arranged in the low zone, or the primary cold source is arranged in the high zone and the primary heat source is arranged in the low zone, and the water source heat pump unit is arranged at the connection part between the high and low zones. The primary cold and heat source arranged in the high zone or the low zone forms a heating and cooling cycle with the air-conditioning users in summer and winter respectively.

[0005] The existing Chinese patent with the publication number CN115388578A discloses a cooling and heating supply system and method coupling a heat source tower heat pump with water energy storage, including an energy storage subsystem, a heat source tower heat pump subsystem and a cooling and heating supply subsystem connected to the energy storage subsystem. The heat source tower heat pump subsystem is used to generate and transport thermal energy or cold energy, the energy storage subsystem is used to store thermal energy or cold energy, and the cooling and heating supply subsystem is used to provide thermal energy or cold energy to the user side for use.

[0006] However, the existing designs do not fully utilize the characteristics of simultaneous refrigeration and heating at both ends of thermal energy. The heat pump and thermal energy storage coupling system is mostly oriented to the energy supply scenarios of alternating winter and summer. The phenomenon of users needing both heating and cooling is widespread. The temperature difference between heating and cooling is obvious and the demand is relatively flexible. Two-stage compression heat pumps or cascade heat pumps can provide low-temperature refrigeration with a large temperature difference and high-temperature heat utilization, but it is difficult to match the demand on the user side in terms of time and quantity.

[0007] Therefore, it is necessary to propose a combined cooling and heating supply system that couples a large-temperature-difference heat pump with phase change thermal energy storage and cold storage to improve the above technical problems. Summary of the Invention

[0008] Aiming at the defects in the prior art, the purpose of the present invention is to provide a combined cooling and heating supply system that couples a large-temperature-difference heat pump with phase change thermal energy storage and cold storage.

[0009] According to a combined cooling and heating supply system that couples a heat pump with phase change thermal energy storage and cold storage provided by the present invention, it includes: a two-stage compression heat pump, a phase change cold storage device 1, a phase change thermal energy storage device 12, a waste heat source 6, an air cooler 17, a fourth heat exchanger 2, and a fifth heat exchanger 13;

[0010] The two-stage compression heat pump includes a first heat exchanger 21, a first compressor 7, a second compressor 8, a third heat exchanger 11, and a first expansion valve 19;

[0011] The first heat exchanger 21, the first compressor 7, the second compressor 8, the third heat exchanger 11, and the first expansion valve 19 are sequentially connected to form a first circulation pipeline;

[0012] The first heat exchanger 21, the phase change cold storage device 1, and the fourth heat exchanger 2 are sequentially connected to form a second circulation pipeline;

[0013] The third heat exchanger 11, the phase change thermal energy storage device 12, and the fifth heat exchanger 13 are sequentially connected to form a third circulation pipeline;

[0014] The fourth heat exchanger 2 and the waste heat source 6 are sequentially connected to form a fourth circulation pipeline;

[0015] The fifth heat exchanger 13 and the air cooler 17 are sequentially connected to form a fifth circulation pipeline.

[0016] Preferably, the phase change thermal energy storage device 12 is filled with a medium-temperature phase change material with a phase change temperature of 55-65 °C.

[0017] Preferably, when the two-stage compression heat pump is replaced with a cascade heat pump, it further includes: a second heat exchanger 9 and a second expansion valve;

[0018] The first heat exchanger 21, the first compressor 7, the second heat exchanger 9, and the first expansion valve 19 are sequentially connected to form a first sub-circulation pipeline;

[0019] The second heat exchanger 9, the second compressor 8, the third heat exchanger 11, and the second expansion valve 18 are connected in sequence to form a second sub-circulation pipeline.

[0020] Preferably, a low-temperature stage refrigerant flows through the first sub-circulation pipeline;

[0021] A high-temperature stage refrigerant flows through the second sub-circulation pipeline.

[0022] Preferably, the phase change heat storage device 12 is filled with a medium-high temperature phase change material with a phase change temperature of 85 - 105 °C.

[0023] Preferably, both the phase change cold storage device 1 and the phase change heat storage device 12 include a heat preservation outer shell, a heat storage working medium, and heat exchange tubes;

[0024] The phase change cold storage device 1 is filled with a low-temperature phase change material with a phase change temperature of 0 - 10 °C;

[0025] The inner tubes of the phase change cold storage device and the phase change heat storage device are serpentine tubes, the material is red copper, and the fin material is aluminum fins;

[0026] The first heat exchanger and the third heat exchanger are shell-and-tube heat exchangers, and the second heat exchanger, the fourth heat exchanger, and the fifth heat exchanger are plate heat exchangers.

[0027] Preferably, a heat transfer working medium ethylene glycol flows through the second circulation pipeline. The heat transfer working medium exchanges heat with the cold storage medium through the heat exchange tubes and fins in the phase change cold storage device 1, and the heat transfer working medium exchanges heat with the fourth circulation pipeline through the fourth heat exchanger 2;

[0028] A heat transfer working medium water flows through the third circulation pipeline. The heat transfer working medium exchanges heat with the heat storage medium through the heat exchange tubes and fins in the phase change heat storage device 12, and the heat transfer working medium exchanges heat with the fifth circulation pipeline through the fifth heat exchanger 13.

[0029] Preferably, it further includes a first circulation pump 20, a second circulation pump 10, a third circulation pump 3, and a fourth circulation pump 14;

[0030] The first circulation pump 20 is between the phase change cold storage device 1 and the first heat exchanger 21;

[0031] The second circulation pump 10 is between the phase change heat storage device 12 and the third heat exchanger 11;

[0032] The third circulation pump 3 is between the fourth heat exchanger 2 and the user cold load 5, or between the fourth heat exchanger 2 and the waste heat source 6;

[0033] The fourth circulation pump 14 is located between the fifth heat exchanger 13 and the air cooler 17, or between the fifth heat exchanger 13 and the user heat load 16.

[0034] Preferably, it further includes: a first three-way valve 4, a second three-way valve 15, a user cold load 5, and a user heat load 16;

[0035] A first three-way valve 4 is serially arranged between the fourth heat exchanger 2 and the waste heat source 6;

[0036] A second three-way valve 15 is serially arranged between the fifth heat exchanger 13 and the air cooler 17;

[0037] The fourth circulation pipeline is connected to the user cold load 5 through the first three-way valve 4;

[0038] The fifth circulation pipeline is connected to the user heat load 16 through the second three-way valve 15.

[0039] According to a control method of a combined cooling and heating supply system coupling a heat pump and phase change heat storage and cold storage provided by the present invention, it includes:

[0040] Step S1: According to user requirements, confirm whether the current combined cooling and heating supply system stores energy. If so, execute step S2; if not, execute step S3.

[0041] Step S2: Determine whether to store heat. If so, execute step S4; if not, store cold alone;

[0042] Step S3: Determine whether to release energy. If so, release heat and cold; if not, end the control.

[0043] Step S4: Determine whether to store cold. If so, store heat and cold simultaneously; if not, store heat alone.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1. The present invention realizes simultaneous cooling and heating with a large temperature difference through a two-stage heat pump or a cascade heat pump, and couples a phase change heat storage and cold storage device to simultaneously meet the flexible cooling and heating needs of users, reduce the waste of cold or heat on the evaporator or condenser side of the heat pump in a single energy supply mode, improve the energy use efficiency, and alleviate the urban "heat island" effect.

[0046] 2. The phase change heat storage and cold storage device is used to solve the mismatch of time and quantity between the cooling and heating supply and demand sides, store thermal energy during off-peak electricity periods, and use it according to users during peak electricity periods, playing the role of peak shaving and valley filling and reducing the electricity cost on the user side. The phase change heat storage and cold storage device is respectively coupled with the evaporator and condenser at both ends of the heat pump, providing a stable operating condition for the heat pump and improving the operating stability of the heat pump.

[0047] 3. The present invention connects the phase change cold storage device, the user's cooling load or supplementary heat source, and the evaporator in series, and connects the heat storage device, the user's heating load or the air cooler, and the condenser in series. By using the supplementary heat source or heat sink to dissipate a small amount of excess heat or cold, both ends of the heat pump have the functions of energy storage and heat and cold dissipation, improving the flexibility of energy supply at both ends of the heat pump and reducing the limitation of the energy storage capacity on heating and cooling at both ends of the heat pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Other features, objects, and advantages of the present invention will become more apparent by reading the detailed description of the non-limiting embodiments with reference to the following drawings:

[0049] Figure 1 is a schematic structural diagram of a combined heating and cooling supply system coupling a two-stage compression heat pump with phase change heat storage and cold storage;

[0050] Figure 2 is a schematic structural diagram of a combined heating and cooling supply system coupling a cascade heat pump with phase change heat storage and cold storage;

[0051] Figure 3 is a schematic flow diagram of the control method of the combined heating and cooling supply system of the present invention.

[0052] As shown in the figure:

[0053] Phase change cold storage device 1, Fourth heat exchanger 2, Third circulation pump 3

[0054] First three-way valve 4, User's cooling load 5, Surplus heat source 6

[0055] First compressor 7, Second compressor 8, Second heat exchanger 9

[0056] Second circulation pump 10, Third heat exchanger 11, Phase change heat storage device 12

[0057] Fifth heat exchanger 13, Fourth circulation pump 14, Second three-way valve 15

[0058] User's heating load 16, Air cooler 17, Second expansion valve 18

[0059] First expansion valve 19, First circulation pump 20, First heat exchanger 21 DETAILED DESCRIPTION OF THE EMBODIMENTS

[0060] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0061] The present invention couples both ends of a two-stage compression heat pump or a cascade heat pump with a phase change energy storage and cold storage device to simultaneously achieve refrigeration and heating with a large temperature difference, improve energy use efficiency, and solve the dual demands of users for cooling and heating. Driven by peak-valley electricity prices, coupling a phase change energy storage and cold storage device at both ends of the heat pump solves the problem of mismatches in the time and quantity of cooling and heating loads, reducing the electricity cost of users. By using a supplementary heat source or heat sink to dissipate a small amount of excess heat or cold, the flexibility of energy supply at both ends of the heat pump is improved.

[0062] Embodiment 1

[0063] A combined cooling and heating supply system coupling a heat pump with phase change heat storage and cold storage according to the present invention includes: a two-stage compression heat pump, a phase change cold storage device 1, a phase change heat storage device 12, a waste heat source 6, an air cooler 17, a fourth heat exchanger 2, and a fifth heat exchanger 13. The two-stage compression heat pump includes a first heat exchanger 21, a first compressor 7, a second compressor 8, a third heat exchanger 11, and a first expansion valve 19.

[0064] The first heat exchanger 21, the first compressor 7, the second compressor 8, the third heat exchanger 11, and the first expansion valve 19 are sequentially connected to form a first circulation pipeline. A fourth heat exchanger 2 is serially arranged with the phase change cold storage device 1 and the first heat exchanger 21, and a fifth heat exchanger 13 is serially arranged with the phase change heat storage device 12 and the third heat exchanger 11. The first heat exchanger 21, the phase change cold storage device 1, and the fourth heat exchanger 2 are sequentially connected to form a second circulation pipeline; the third heat exchanger 11, the phase change heat storage device 12, and the fifth heat exchanger 13 are sequentially connected to form a third circulation pipeline; the fourth heat exchanger 2 and the waste heat source 6 are sequentially connected to form a fourth circulation pipeline; the fifth heat exchanger 13 and the air cooler 17 are sequentially connected to form a fifth circulation pipeline.

[0065] Among them, the phase change cold storage device 1 includes a heat preservation shell, a heat storage working medium, and heat exchange tubes. The phase change cold storage device 1 is filled with a low-temperature phase change material with a phase change temperature of 0 - 10°C. The phase change heat storage device 12 includes a heat preservation shell, a heat storage working medium, and heat exchange tubes. The phase change heat storage device 12 is filled with a medium-temperature phase change material with a phase change temperature of 55 - 65°C. Preferably, the phase change heat storage device 12 is filled with a medium-high temperature phase change material with a phase change temperature of 85 - 105°C or a medium-temperature phase change material with a phase change temperature of 55 - 65°C. A heat transfer working medium, ethylene glycol, circulates in the second circulation pipeline. The heat transfer working medium exchanges heat with the cold storage medium through the heat exchange tubes and fins in the phase change cold storage device 1, and the heat transfer working medium exchanges heat with the fourth circulation pipeline through the fourth heat exchanger 2. A heat transfer working medium, water, circulates in the third circulation pipeline. The heat transfer working medium exchanges heat with the heat storage medium through the heat exchange tubes and fins in the phase change heat storage device 12, and the heat transfer working medium exchanges heat with the fifth circulation pipeline through the fifth heat exchanger 13.

[0066] It further includes a first circulation pump 20, a second circulation pump 10, a third circulation pump 3, and a fourth circulation pump 14; the first circulation pump 20 is between the phase change cold storage device 1 and the first heat exchanger 21; the second circulation pump 10 is between the phase change heat storage device 12 and the third heat exchanger 11; the third circulation pump 3 is between the fourth heat exchanger 2 and the user cooling load 5, or between the fourth heat exchanger 2 and the waste heat source 6; the fourth circulation pump 14 is between the fifth heat exchanger 13 and the air cooler 17, or between the fifth heat exchanger 13 and the user heating load 16. That is to say, the user cooling load and the waste heat source are connected in parallel, and one of them exchanges heat with the fourth heat exchanger, and the fluid is transmitted through the third circulation pump. The user heating load and the air cooler are connected in parallel, and one of them exchanges heat with the fifth heat exchanger, and the fluid is transmitted through the fourth circulation pump. The third circulation pump enables the fluid to exchange heat at two places, namely the fourth heat exchanger and the user cooling load or the waste heat source. The fourth circulation pump enables the fluid to exchange heat at two places, namely the fifth heat exchanger and the user heating load or the air cooler.

[0067] The inner pipes of the phase change cold storage device and the phase change heat storage device are serpentine pipes, the material is red copper, and the fin material is aluminum fins. The first heat exchanger and the third heat exchanger are shell-and-tube heat exchangers, and the fourth heat exchanger and the fifth heat exchanger are plate heat exchangers.

[0068] A combined cooling and heating supply system coupling a heat pump with phase change heat storage and cold storage according to the present invention further includes: a first three-way valve 4, a second three-way valve 15, a user cooling load 5, and a user heating load 16; a first three-way valve 4 is serially arranged between the fourth heat exchanger 2 and the waste heat source 6; a second three-way valve 15 is serially arranged between the fifth heat exchanger 13 and the air cooler 17; the fourth circulation pipeline is connected to the user cooling load 5 through the first three-way valve 4; the fifth circulation pipeline is connected to the user heating load 16 through the second three-way valve 15.

[0069] Further, in combination with the attached Figure 1 For the combined cooling and heating supply system coupling a heat pump with phase change heat storage and cold storage of the present invention, where the heat pump is a two-stage compression heat pump, the system includes: a phase change cold storage device 1, a fourth heat exchanger 2, a third circulation pump 3, a first three-way valve 4, a user cooling load 5, a waste heat source 6, a first compressor 7, a second compressor 8, a second circulation pump 10, a third heat exchanger 11, a phase change heat storage device 12, a fifth heat exchanger 13, a fourth circulation pump 14, a second three-way valve 15, a user heating load 16, an air cooler 17, a first expansion valve 19, a first circulation pump 20, and a first heat exchanger 21; the first heat exchanger 21 is a shell-and-tube heat exchanger; the third heat exchanger 11 is a shell-and-tube heat exchanger; the fourth heat exchanger 2 is a plate heat exchanger; the fifth heat exchanger 13 is a plate heat exchanger.

[0070] The first heat exchanger 21, the first compressor 7, the second compressor 8, the second heat exchanger 9, and the first expansion valve 19 are connected in sequence to form a first circulation pipeline. The first heat exchanger 21, the phase change energy storage device 1, and the fourth heat exchanger 2 are connected in sequence to form a third circulation pipeline; the third heat exchanger 11, the phase change heat storage device 12, and the fifth heat exchanger 13 are connected in sequence to form a fourth circulation pipeline. The fourth heat exchanger 2 and the waste heat source 6 are connected in sequence to form a fifth circulation pipeline; the fifth circulation pipeline is connected to the user cooling load 5 through the first three-way valve 4; the fifth heat exchanger 13 and the air cooler 17 are connected in sequence to form a sixth circulation pipeline; the sixth circulation pipeline is connected to the user heating load 16 through the second three-way valve 15.

[0071] A first circulation pump 20 is provided between the phase change energy storage device 1 and the first heat exchanger 21; a second circulation pump 10 is provided between the phase change heat storage device 12 and the third heat exchanger 11; a third circulation pump 3 is provided between the fourth heat exchanger 2 and the user cooling load 5; a third circulation pump 3 is provided between the fourth heat exchanger 2 and the user cooling load 5; a fourth circulation pump 14 is provided between the fifth heat exchanger 13 and the air cooler 17; a fourth circulation pump 14 is provided between the fifth heat exchanger 13 and the user heating load 16.

[0072] The phase change energy storage device 1 includes a heat-insulating outer shell, a heat storage working medium, and heat exchange tubes. The phase change energy storage device 1 is filled with a low-temperature phase change material with a phase change temperature of 0 - 10°C. Preferably, the inner tube of the phase change energy storage device 1 is a serpentine tube, the material is copper, and the fin material is aluminum fin. The phase change material filled in the phase change energy storage device 1 is water, D2O, LiClO3·3H2O, tetrahydrofuran, formic acid, polyethylene glycol 400, dimethyl adipate, tetradecane, pentadecane, etc., and its phase change temperature range is 0 - 10°C, and the phase change latent heat is 99.6 - 335 kJ / kg.

[0073] The phase change heat storage device 12 includes a heat-insulating outer shell, a heat storage working medium, and heat exchange tubes. The phase change heat storage device 12 is filled with a medium-temperature phase change material with a phase change temperature of 55 - 65°C. Preferably, the inner tube of the phase change heat storage device 12 is a serpentine tube, the material is copper, and the fin material is aluminum fin. The phase change material filled in the phase change heat storage device 12 is sodium acetate trihydrate, heptacosane, myristic acid, etc., and its phase change temperature range is 55 - 60°C, and the phase change latent heat is 199 - 286 kJ / kg.

[0074] A refrigerant flows through the first circulation pipeline of the two-stage compression heat pump. Preferably, the refrigerant flowing through the first circulation pipeline is R134a, R744, R407c, R1234ze(E), etc.

[0075] This embodiment is used for medium-temperature heat supply and low-temperature refrigeration in industrial or commercial buildings, and can be used to meet the heat supply needs such as space heating and refrigeration and ice-making needs. During the valley electricity period, heat storage and cold storage are carried out simultaneously or separately for heat storage or cold storage alone according to the capacities of the phase change cold storage device 1 and the phase change heat storage device 12, saving energy and reducing the number of devices for heat supply and refrigeration. During the peak electricity period, heat is released and cold is released flexibly according to the heat supply and refrigeration needs of users, taking advantage of the peak-valley differential electricity price to reduce the external power purchase cost.

[0076] The simultaneous heat storage and cold storage operation of this embodiment is as follows:

[0077] Under the condition of simultaneous heat storage and cold storage, turn on the first circulation pump 20, the second circulation pump 10, the first compressor 7, the second compressor 8, and the first expansion valve 19, and turn off the third circulation pump 3, the fourth circulation pump 14, the waste heat source 6, and the air cooler 17. The phase change cold storage device 1, the fourth heat exchanger 2, the first heat exchanger 21, and the first circulation pump 20 form a third circulation pipeline, and the heat transfer fluid flows through the fourth heat exchanger 2 without heat exchange. The phase change heat storage device 12, the fifth heat exchanger 13, the third heat exchanger 11, and the second circulation pump 10 form a fourth circulation pipeline, and the heat transfer fluid flows through the fifth heat exchanger 13 without heat exchange. The first heat exchanger 21 absorbs heat in the phase change cold storage device 1 to store cold, and the phase change material changes from liquid to solid, and the internal temperature of the phase change cold storage device 1 is stabilized near the phase change temperature of the phase change material. The heat absorbed by the first heat exchanger 21 is upgraded by a two-stage compression heat pump cycle. The third heat exchanger 11 releases heat to the phase change heat storage device 12 for heat storage through the heat transfer fluid, and the phase change material changes from solid to liquid, and the internal temperature of the phase change heat storage device 12 is stabilized near the phase change temperature of the phase change material.

[0078] The separate heat storage operation of this embodiment is as follows:

[0079] Considering the change in the required cold storage and heat storage amounts caused by the daily change in the user's heat and cold consumption, in the single heat storage mode after the cold storage amount is satisfied, the first circulation pump 20, the second circulation pump 10, the third circulation pump 3, the first compressor 7, the second compressor 8, the first expansion valve 19, and the waste heat source 6 are turned on, and the fourth circulation pump 14 and the air cooler 17 are turned off. The first three-way valve 4 connects the third circulation pump 3 and the waste heat source 6, and the third circulation pump 3, the waste heat source 6, and the fourth heat exchanger 2 form a fifth circulation pipeline. The phase change cold storage device 1, the fourth heat exchanger 2, the first heat exchanger 21, and the first circulation pump 20 form a third circulation pipeline, and the heat transfer fluid flows through the fourth heat exchanger 2 to exchange heat with the waste heat source 6. The phase change heat storage device 12, the fifth heat exchanger 13, the third heat exchanger 11, and the second circulation pump 10 form a fourth circulation pipeline, and the heat transfer fluid flows through the fifth heat exchanger 13 without heat exchange. The first heat exchanger 21 absorbs heat from the waste heat source 6 through the third circulation pipeline and the fifth circulation pipeline, and the grade is raised by a two-stage compression heat pump cycle. The third heat exchanger 11 releases heat to the phase change heat storage device 12 through the heat transfer fluid for heat storage, and the phase change material changes from solid to liquid, and the internal temperature of the phase change heat storage device 12 is stabilized near the phase change temperature of the phase change material.

[0080] The single cold storage operation of this embodiment is as follows:

[0081] Considering the change in the required cold storage and heat storage amounts caused by the daily change in the user's heat and cold consumption, in the single cold storage mode after the heat storage amount is satisfied, the first circulation pump 20, the second circulation pump 10, the fourth circulation pump 14, the first compressor 7, the second compressor 8, the first expansion valve 19, and the air cooler 17 are turned on, and the third circulation pump 3 and the waste heat source 6 are turned off. The second three-way valve 15 connects the air cooler 17 and the fourth circulation pump 14, and the fourth circulation pump 14, the air cooler 17, and the fifth heat exchanger 13 form a sixth circulation pipeline. The phase change cold storage device 1, the fourth heat exchanger 2, the first heat exchanger 21, and the first circulation pump 20 form a third circulation pipeline, and the heat transfer fluid flows through the fourth heat exchanger 2 without heat exchange. The phase change heat storage device 12, the fifth heat exchanger 13, the third heat exchanger 11, and the second circulation pump 10 form a fourth circulation pipeline, and the heat transfer fluid flows through the fifth heat exchanger 13 to exchange heat with the air cooler 17. The first heat exchanger 21 absorbs heat in the phase change cold storage device 1 through the heat transfer fluid for cold storage, and the phase change material changes from liquid to solid, and the internal temperature of the phase change cold storage device 1 is stabilized near the phase change temperature of the phase change material. The heat absorbed by the first heat exchanger 21 is raised in grade by a two-stage compression heat pump cycle, and the third heat exchanger 11 releases heat to the air cooler 17 through the fourth circulation pipeline and the sixth circulation pipeline.

[0082] The heat release and cold release operations of this embodiment are as follows:

[0083] When there is a demand for heating or cooling by users during the peak electricity period, in the heat release and cooling release working conditions, the first circulation pump 20, the second circulation pump 10, the third circulation pump 3, and the fourth circulation pump 14 are turned on, and the first compressor 7, the second compressor 8, the first expansion valve 19, the surplus heat source 6, and the air cooler 17 are turned off. The first three-way valve 4 connects the third circulation pump 3 and the user's cooling load 5. The fourth heat exchanger 2, the third circulation pump 3, the user's cooling load 5, and the surplus heat source 6 form a fifth circulation pipeline, and the heat transfer fluid flows through the surplus heat source 6 without heat exchange. The second three-way valve 15 connects the fourth circulation pump 14 and the user's heating load 16. The fifth heat exchanger 13, the fourth circulation pump 14, the user's heating load 16, and the air cooler 17 form a sixth circulation pipeline, and the heat transfer fluid flows through the air cooler 17 without heat exchange. The first heat exchanger 21, the first circulation pump 20, the phase change cold storage device 1, and the fourth heat exchanger 2 form a third circulation pipeline, and the heat transfer fluid flows through the first heat exchanger 21 without heat exchange. The third heat exchanger 11, the second circulation pump 10, the phase change heat storage device 12, and the fifth heat exchanger 13 form a fourth circulation pipeline, and the heat transfer fluid flows through the third heat exchanger 11 without heat exchange. When there is a useful cooling demand from the user, the heat transfer fluid in the fifth circulation pipeline releases heat to the third circulation pipeline through the fourth heat exchanger 2, and the phase change cold storage device 1 realizes cooling release, and the phase change material changes from solid to liquid. When there is a useful heating demand from the user, the heat transfer fluid in the fourth circulation pipeline releases heat to the sixth circulation pipeline through the fifth heat exchanger 13, and the phase change heat storage device 12 realizes heat release, and the phase change material changes from liquid to solid.

[0084] Embodiment 2

[0085] There is a variation in the present invention, and the variation lies in: based on the combined heating and cooling supply system of a heat pump and phase change heat storage and cold storage described in Embodiment 1, replacing the two-stage compression heat pump with a cascade heat pump, and the cascade heat pump includes a first heat exchanger 21, a first compressor 7, a second compressor 8, a third heat exchanger 11, a first expansion valve 19, a second heat exchanger 9, and a second expansion valve 18; the first heat exchanger 21, the first compressor 7, the second heat exchanger 9, and the first expansion valve 19 are sequentially connected to form a first sub-circulation pipeline; the second heat exchanger 9, the second compressor 8, the third heat exchanger 11, and the second expansion valve 18 are sequentially connected to form a second sub-circulation pipeline. Among them, in this variation, the phase change heat storage device 12 is filled with a medium-high temperature phase change material with a phase change temperature of 85 - 105 °C.

[0086] The first sub-circulation pipeline circulates a low-temperature refrigerant; the second sub-circulation pipeline circulates a high-temperature refrigerant. Preferably, the second heat exchanger is a plate heat exchanger.

[0087] Further, in combination with the attached Figure 2 For the combined heating and cooling supply system of the heat pump and phase change heat storage and cold storage in this variation, where the heat pump is a cascade heat pump, it is further described as follows:

[0088] Based on the combined cooling and heating supply system with large temperature difference heat pump and phase change heat storage and cold storage in Embodiment 1, it further includes: a second heat exchanger 9 and a second expansion valve 18. The second heat exchanger 9 and the second expansion valve 18 constitute the cascade heat pump unit of this embodiment; the second heat exchanger 9 is a plate heat exchanger. In this embodiment, the first heat exchanger 21, the first compressor 7, the second heat exchanger 9, and the first expansion valve 19 are connected in sequence to form a first circulation pipeline; the second heat exchanger 9, the second compressor 8, the third heat exchanger 11, and the second expansion valve 18 are connected in sequence to form a second circulation pipeline. The first heat exchanger 21, the phase change cold storage device 1, and the fourth heat exchanger 2 are connected in sequence to form a third circulation pipeline; the third heat exchanger 11, the phase change heat storage device 12, and the fifth heat exchanger 13 are connected in sequence to form a fourth circulation pipeline. The fourth heat exchanger 2 and the waste heat source 6 are connected in sequence to form a fifth circulation pipeline; the fifth circulation pipeline is connected to the user's cooling load 5 through a first three-way valve 4; the fifth heat exchanger 13 and the air cooler 17 are connected in sequence to form a sixth circulation pipeline; the sixth circulation pipeline is connected to the user's heating load 16 through a second three-way valve 15.

[0089] A first circulation pump 20 is provided between the phase change cold storage device 1 and the first heat exchanger 21; a second circulation pump 10 is provided between the phase change heat storage device 12 and the third heat exchanger 11; a third circulation pump 3 is provided between the fourth heat exchanger 2 and the user's cooling load 5; a third circulation pump 3 is provided between the fourth heat exchanger 2 and the user's cooling load 5; a fourth circulation pump 14 is provided between the fifth heat exchanger 13 and the air cooler 17; a fourth circulation pump 14 is provided between the fifth heat exchanger 13 and the user's heating load 16.

[0090] The phase change cold storage device 1 includes a heat insulation outer shell, a heat storage working medium, and heat exchange tubes. The phase change cold storage device 1 is filled with a low-temperature phase change material with a phase change temperature of 0 - 10°C. Preferably, the inner tube of the phase change cold storage device 1 is a serpentine tube, the material is copper, and the fin material is aluminum fin. The phase change material filled in the phase change cold storage device 1 is water, D2O, LiClO3·3H2O, tetrahydrofuran, formic acid, polyethylene glycol 400, dimethyl adipate, tetradecane, pentadecane, etc., and its phase change temperature range is 0 - 10°C, and the phase change latent heat is 99.6 - 335 kJ / kg.

[0091] The phase change heat storage device 12 includes a heat insulation outer shell, a heat storage working medium, and heat exchange tubes. The phase change heat storage device 12 is filled with a medium-high temperature phase change material with a phase change temperature of 85 - 105°C. Preferably, the inner tube of the phase change heat storage device 12 is a serpentine tube, the material is copper, and the fin material is aluminum fin. The phase change material filled in the phase change heat storage device 12 is Mg(NO3)2·6H2O, acetamide, xylitol, etc., and its phase change temperature range is 85 - 105°C, and the phase change latent heat is 148 - 241 kJ / kg.

[0092] In the cascade heat pump, the low-temperature stage refrigerant flows through the first circulation pipeline, and the high-temperature stage refrigerant flows through the second circulation pipeline. Preferably, the refrigerant flowing through the first circulation pipeline is R1234ze(E), R134a, R407c, R404a, etc.; the refrigerant flowing through the second circulation pipeline is R245fa, HP-1, R1233zd(E), R744, R717, R718, etc.

[0093] This embodiment is used for medium-high temperature heating and low-temperature refrigeration in industrial or commercial buildings, and can be used to meet the heating requirements such as high-temperature steam and hot water, as well as the refrigeration and ice-making requirements. During the valley electricity period, heat storage and cold storage are carried out simultaneously or separately according to the capacities of the phase change cold storage device 1 and the phase change heat storage device 12, saving energy and reducing the number of devices for heating and refrigeration. During the peak electricity period, heat is released and cold is released flexibly according to the heating and refrigeration requirements of users, taking advantage of the peak-valley differential electricity price to reduce the external power purchase cost.

[0094] The simultaneous heat storage and cold storage operation of this embodiment is as follows:

[0095] Under the condition of simultaneous heat storage and cold storage, turn on the first circulation pump 20, the second circulation pump 10, the first compressor 7, the second compressor 8, the first expansion valve 19, and the second expansion valve 18, and turn off the third circulation pump 3, the fourth circulation pump 14, the waste heat source 6, and the air cooler 17. The phase change cold storage device 1, the fourth heat exchanger 2, the first heat exchanger 21, and the first circulation pump 20 form the third circulation pipeline, and the heat transfer fluid flows through the fourth heat exchanger 2 but does not exchange heat. The phase change heat storage device 12, the fifth heat exchanger 13, the third heat exchanger 11, and the second circulation pump 10 form the fourth circulation pipeline, and the heat transfer fluid flows through the fifth heat exchanger 13 but does not exchange heat. The first heat exchanger 21 absorbs heat in the phase change cold storage device 1 through the heat transfer fluid to store cold, and the phase change material changes from liquid to solid, and the internal temperature of the phase change cold storage device 1 is stable near the phase change temperature of the phase change material. The heat absorbed by the first heat exchanger 21 is upgraded by the first circulation pipeline of the cascade heat pump and released to the refrigerant flowing through the second circulation pipeline via the second heat exchanger 9. The heat absorbed by the second heat exchanger 9 is upgraded by the second circulation pipeline of the cascade heat pump, and the third heat exchanger 11 releases heat to the phase change heat storage device 12 through the heat transfer fluid to store heat, and the phase change material changes from solid to liquid, and the internal temperature of the phase change heat storage device 12 is stable near the phase change temperature of the phase change material.

[0096] The separate heat storage operation of this embodiment is as follows:

[0097] Considering the change in the required cold and heat storage capacities caused by the daily variation of the user's heat and cold consumption, in the case of separate heat storage operation after the cold storage capacity is satisfied, the first circulation pump 20, the second circulation pump 10, the third circulation pump 3, the first compressor 7, the second compressor 8, the first expansion valve 19, the second expansion valve 18, and the waste heat source 6 are turned on, and the fourth circulation pump 14 and the air cooler 17 are turned off. The first three-way valve 4 connects the third circulation pump 3 and the waste heat source 6, and the third circulation pump 3, the waste heat source 6, and the fourth heat exchanger 2 form a fifth circulation pipeline. The phase change cold storage device 1, the fourth heat exchanger 2, the first heat exchanger 21, and the first circulation pump 20 form a third circulation pipeline, and the heat transfer fluid flows through the fourth heat exchanger 2 to exchange heat with the waste heat source 6. The phase change heat storage device 12, the fifth heat exchanger 13, the third heat exchanger 11, and the second circulation pump 10 form a fourth circulation pipeline, and the heat transfer fluid flows through the fifth heat exchanger 13 without heat exchange. The first heat exchanger 21 absorbs heat from the waste heat source 6 through the third circulation pipeline and the fifth circulation pipeline, the grade is raised by the first circulation pipeline of the cascade heat pump, and the heat is released to the refrigerant flowing through the second circulation pipeline via the second heat exchanger 9. The heat absorbed by the second heat exchanger 9 is raised in grade by the second circulation pipeline of the cascade heat pump, and the third heat exchanger 11 releases heat to the phase change heat storage device 12 through the heat transfer fluid for heat storage, the phase change material changes from solid to liquid, and the internal temperature of the phase change heat storage device 12 is stabilized near the phase change temperature of the phase change material.

[0098] The separate cold storage operation of this embodiment is as follows:

[0099] Considering the change in the required cold and heat storage capacities caused by the daily variation in the user's heat and cold consumption, in the single cold storage mode after the heat storage capacity is satisfied, the first circulation pump 20, the second circulation pump 10, the fourth circulation pump 14, the first compressor 7, the second compressor 8, the first expansion valve 19, the second expansion valve 18, and the air cooler 17 are turned on, and the third circulation pump 3 and the waste heat source 6 are turned off. The second three-way valve 15 connects the air cooler 17 and the fourth circulation pump 14, and the fourth circulation pump 14, the air cooler 17, and the fifth heat exchanger 13 form a sixth circulation pipeline. The phase change cold storage device 1, the fourth heat exchanger 2, the first heat exchanger 21, and the first circulation pump 20 form a third circulation pipeline, and the heat transfer fluid flows through the fourth heat exchanger 2 without heat exchange. The phase change heat storage device 12, the fifth heat exchanger 13, the third heat exchanger 11, and the second circulation pump 10 form a fourth circulation pipeline, and the heat transfer fluid exchanges heat with the air cooler 17 through the fifth heat exchanger 13. The first heat exchanger 21 absorbs heat in the phase change cold storage device 1 for cold storage, and the phase change material changes from liquid to solid, and the internal temperature of the phase change cold storage device 1 is stabilized near the phase change temperature of the phase change material. The heat absorbed by the first heat exchanger 21 is upgraded by the first circulation pipeline of the cascade heat pump and released to the refrigerant flowing in the second circulation pipeline through the second heat exchanger 9. The heat absorbed by the second heat exchanger 9 is upgraded by the second circulation pipeline of the cascade heat pump, and the third heat exchanger 11 releases heat to the air cooler 17 through the fourth circulation pipeline and the sixth circulation pipeline.

[0100] The heat release and cold release operations of this embodiment are as follows:

[0101] When there is a user's heating or cooling demand during the peak electricity period, in the heat release and cooling release working conditions, turn on the first circulation pump 20, the second circulation pump 10, the third circulation pump 3, and the fourth circulation pump 14, and turn off the first compressor 7, the second compressor 8, the first expansion valve 19, the second expansion valve 18, the waste heat source 6, and the air cooler 17. The first three-way valve 4 connects the third circulation pump 3 and the user's cooling load 5. The fourth heat exchanger 2, the third circulation pump 3, the user's cooling load 5, and the waste heat source 6 form a fifth circulation pipeline, and the heat transfer fluid flows through the waste heat source 6 but does not exchange heat. The second three-way valve 15 connects the fourth circulation pump 14 and the user's heating load 16. The fifth heat exchanger 13, the fourth circulation pump 14, the user's heating load 16, and the air cooler 17 form a sixth circulation pipeline, and the heat transfer fluid flows through the air cooler 17 but does not exchange heat. The first heat exchanger 21, the first circulation pump 20, the phase change cold storage device 1, and the fourth heat exchanger 2 form a third circulation pipeline, and the heat transfer fluid flows through the first heat exchanger 21 but does not exchange heat. The third heat exchanger 11, the second circulation pump 10, the phase change heat storage device 12, and the fifth heat exchanger 13 form a fourth circulation pipeline, and the heat transfer fluid flows through the third heat exchanger 11 but does not exchange heat. When there is a user's cooling demand, the heat transfer fluid in the fifth circulation pipeline releases heat to the third circulation pipeline through the fourth heat exchanger 2, and the phase change cold storage device 1 realizes cooling release, and the phase change material changes from solid to liquid. When there is a user's heating demand, the heat transfer fluid in the fourth circulation pipeline releases heat to the sixth circulation pipeline through the fifth heat exchanger 13, and the phase change heat storage device 12 realizes heat release, and the phase change material changes from liquid to solid.

[0102] Embodiment III

[0103] A control method for a combined heating and cooling supply system coupling a heat pump and phase change heat storage and cold storage according to the present invention, as Figure 3 shown, includes:

[0104] Step S1: According to the user's demand, confirm whether the current combined heating and cooling supply system stores energy. If so, execute Step S2; if not, execute Step S3.

[0105] Step S2: Judge whether to store heat. If so, execute Step S4; if not, store cold alone;

[0106] Step S3: Judge whether to release energy. If so, release heat and cool; if not, end the control.

[0107] Step S4: Judge whether to store cold. If so, store heat and cold simultaneously; if not, store heat alone.

[0108] The two-stage compression heat pump or cascade heat pump can flexibly change three energy storage modes according to the capacity change of the phase change cold storage and heat storage devices at both ends, namely simultaneous heat storage and cold storage, separate heat storage, and separate cold storage. It can flexibly release heat and cold according to the heat and cold demand of users, solving the problem of mismatch between the time and capacity of the heat and cold loads caused by simultaneous refrigeration and heating.

[0109] Based on the first and second embodiments, the present application realizes simultaneous refrigeration and heating with a large temperature difference by coupling a two-stage compression heat pump or a cascade heat pump with phase change cold storage and heat storage devices at both ends. It can be used in fields such as medium-temperature heat supply (such as air heating and heating in commercial buildings or industrial production), medium-high temperature heat supply (such as supplying boiling water and steam), and refrigeration and ice making, improving energy use efficiency and solving the dual demands of users for heat and cold. Driven by peak-valley electricity prices, the heat pump coupled with phase change cold storage and heat storage devices at both ends solves the problem of mismatch between the time and quantity of heat and cold loads, reducing the electricity cost of users. By using supplementary heat sources or heat sinks to consume a small amount of excess heat or cold, the heat pump at both ends has the functions of both energy storage and heat and cold dissipation, improving the flexibility of heat supply at both ends of the heat pump and reducing the limitation of the energy storage capacity on heat supply and refrigeration at both ends of the heat pump. When the two-stage compression heat pump or cascade heat pump adopted in the present invention is coupled with the phase change cold storage and heat storage device, the modification of the original equipment structure is small, and there is great potential for industrial scale-up.

[0110] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application 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 should not be construed as a limitation to the present application.

[0111] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other.

Claims

1. A combined cooling and heating supply system coupling a heat pump with phase change heat storage and cold storage, characterized in that, Including: Two-stage compression heat pump, phase change cold storage device 1, phase change heat storage device 12, waste heat source 6, air cooler 17, fourth heat exchanger 2, fifth heat exchanger 13; The two-stage compression heat pump includes a first heat exchanger 21, a first compressor 7, a second compressor 8, a third heat exchanger 11, and a first expansion valve 19; The first heat exchanger 21, the first compressor 7, the second compressor 8, the third heat exchanger 11, and the first expansion valve 19 are connected in sequence to form a first circulation pipeline; The first heat exchanger 21, the phase change cold storage device 1, and the fourth heat exchanger 2 are connected in sequence to form a second circulation pipeline; The third heat exchanger 11, the phase change heat storage device 12, and the fifth heat exchanger 13 are connected in sequence to form a third circulation pipeline; The fourth heat exchanger 2 and the waste heat source 6 are connected in sequence to form a fourth circulation pipeline; The fifth heat exchanger 13 and the air cooler 17 are connected in sequence to form a fifth circulation pipeline.

2. The combined heating and cooling supply system integrating a heat pump with phase change heat storage and cold storage according to claim 1, wherein The phase change heat storage device 12 is filled with a medium-temperature phase change material with a phase change temperature of 55 - 65 °C.

3. The combined heating and cooling supply system coupling a heat pump with phase change heat storage and cold storage according to claim 1, characterized in that, Replacing the two-stage compression heat pump with a cascade heat pump, it further includes: a second heat exchanger 9 and a second expansion valve; The first heat exchanger 21, the first compressor 7, the second heat exchanger 9, and the first expansion valve 19 are connected in sequence to form a first sub-circulation pipeline; The second heat exchanger 9, the second compressor 8, the third heat exchanger 11, and the second expansion valve 18 are connected in sequence to form a second sub-circulation pipeline.

4. The combined heating and cooling supply system integrating a heat pump with phase change heat storage and cold storage according to claim 3, characterized in that, The first sub-circulation pipeline circulates a low-temperature stage refrigerant; The second sub-circulation pipeline circulates a high-temperature stage refrigerant.

5. The combined cooling and heating supply system integrating a heat pump with phase change heat storage and cold storage according to claim 3, characterized in that, The phase change heat storage device 12 is filled with a medium-high temperature phase change material with a phase change temperature of 85 - 105 °C.

6. The combined heating and cooling supply system coupling a heat pump with phase change heat storage and cold storage according to claim 1 or 3, characterized in that, Both the phase change cold storage device 1 and the phase change heat storage device 12 include a heat preservation shell, a heat storage working medium, and heat exchange tubes; The phase change cold storage device 1 is filled with a low-temperature phase change material with a phase change temperature of 0 - 10 °C; The inner tubes of the phase change cold storage device and the phase change heat storage device are serpentine tubes, the material is red copper, and the fin material is aluminum fins; The first heat exchanger and the third heat exchanger are shell-and-tube heat exchangers, and the second heat exchanger, the fourth heat exchanger, and the fifth heat exchanger are plate heat exchangers.

7. The combined heating and cooling supply system coupling a heat pump with phase change heat storage and cold storage according to claim 1 or 3, characterized in that, The second circulation pipeline circulates a heat transfer working medium ethylene glycol. The heat transfer working medium exchanges heat with the cold storage medium through the heat exchange tubes and fins in the phase change cold storage device 1, and the heat transfer working medium exchanges heat with the fourth circulation pipeline through the fourth heat exchanger 2; The third circulation pipeline circulates a heat transfer working medium water. The heat transfer working medium exchanges heat with the heat storage medium through the heat exchange tubes and fins in the phase change heat storage device 12, and the heat transfer working medium exchanges heat with the fifth circulation pipeline through the fifth heat exchanger 13.

8. The combined cooling and heating supply system coupling a heat pump with phase change heat storage and cold storage according to claim 1 or 3, characterized in that, It further includes a first circulation pump 20, a second circulation pump 10, a third circulation pump 3, and a fourth circulation pump 14; The first circulation pump 20 is between the phase change cold storage device 1 and the first heat exchanger 21; The second circulation pump 10 is between the phase change heat storage device 12 and the third heat exchanger 11; The third circulation pump 3 is between the fourth heat exchanger 2 and the user cold load 5, or between the fourth heat exchanger 2 and the waste heat source 6; The fourth circulation pump 14 is between the fifth heat exchanger 13 and the air cooler 17, or between the fifth heat exchanger 13 and the user heat load 16.

9. The combined heating and cooling supply system coupling a heat pump with phase change heat storage and cold storage according to claim 1 or 3, characterized in that, Further included are: a first three-way valve 4, a second three-way valve 15, a user cold load 5, and a user heat load 16; A first three-way valve 4 is serially arranged between the fourth heat exchanger 2 and the waste heat source 6; A second three-way valve 15 is serially arranged between the fifth heat exchanger 13 and the air cooler 17; The fourth circulation pipeline is connected to the user cold load 5 through the first three-way valve 4; The fifth circulation pipeline is connected to the user heat load 16 through the second three-way valve 15.

10. A control method for a combined cooling and heating supply system coupling a heat pump with phase change heat storage and cold storage, characterized in that, For the combined cooling and heating supply system coupling a heat pump and phase change heat storage and cold storage using the system according to claim 1, the control method includes: Step S1: According to user requirements, confirm whether the current combined cooling and heating supply system is for energy storage. If so, execute step S2; if not, execute step S3. Step S2: Judge whether to store heat. If so, execute step S4; if not, store cold alone; Step S3: Judge whether to release energy. If so, release heat and cold; if not, end the control. Step S4: Judge whether to store cold. If so, store heat and cold simultaneously; if not, store heat alone.

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