A multi-class thermal energy storage and interconnection system for thermal units and an automatic energy storage heating control method

Abstract

A multi-class thermal energy storage interconnection system and an automatic energy storage heating control method, comprising: a first medium source thermal energy unit (1), a second medium source thermal energy unit (5), an energy storage unit (9), and a terminal device (12). The first medium source thermal energy unit (1), the second medium source thermal energy unit (5), and the terminal device (12) are sequentially connected in series through a water supply pipeline and a water return pipeline. The energy storage unit (9) is connected in parallel between the water supply pipeline and the water return pipeline of the second medium source thermal energy unit (5) and the terminal device (12). Through energy storage and optimized coordinated control of the unit, the present invention can reduce the power capacity increase of the entire system, thereby reducing investment, improving the low efficiency of air source heat pumps under cold conditions, and realizing the full utilization of electricity prices during low electricity price periods.

Description

Technical Field

[0001] The invention relates to the technical field of heating, and particularly relates to a multi-class thermal energy unit energy storage interconnection system and an automatic energy storage heating control method. Background Art

[0002] In the prior art, heating and hot water supply by means of coal combustion, gas, etc. will cause relatively serious environmental pollution. Using an electric heat pump method to replace coal combustion and gas methods is cleaner and more efficient than direct electric heating methods such as electric boilers and heating cables. When using a pure air source heat pump for heating, in cold conditions, the efficiency of the air source heat pump will drop very low, and the outlet water temperature cannot meet the requirements of the end equipment with radiators, resulting in the inability to achieve the expected heating effect and a significant increase in costs.

[0003] However, in practical applications, the existing energy storage heat pump systems have the following problems: (1) The main function of the energy storage water tank in this system is to serve as a buffer water tank, with a storage water temperature of only 15 degrees, a very small energy storage temperature difference, and very little energy storage. If it is to have application value, the volume of the water tank will be very large. (2) This system cannot make full use of the electricity price during low electricity price periods. Due to the load characteristics of the power system, the electricity price during off-peak hours at night is cheap; with the development of the future electricity spot market, the electricity price will fluctuate in real time according to the electricity supply and demand situation, and the electricity price during low electricity price periods will be very low, with great utilization value. The energy storage capacity of this type of system is very small and does not have practical application value. (3) During non-normal heating periods such as at night and on holidays, the heat pump system needs to operate for low-temperature anti-freezing, and at this time, the load is very low, showing a situation of large units and small loads, and the system will start and stop frequently, increasing energy consumption. (4) When using a heat pump system for heating, generally, electricity capacity expansion is required.

[0004] In summary, various heat pump systems in the current prior art cannot simultaneously solve the problems of low outlet water temperature and low efficiency of the air source heat pump system during low-temperature operation, difficulty in making full use of the electricity price during low electricity price periods, frequent start and stop during low-temperature anti-freezing operation, and optimizing and reducing the investment in electricity capacity expansion. Summary of the Invention

[0005] In view of this, the present invention proposes a multi-class thermal energy unit energy storage interconnection system, which organically combines an air source heat pump, a water source heat pump, and an energy storage facility. Through an automatic control method with multiple working conditions and multiple working modes, it can solve the problems of low outlet water temperature and low efficiency of the air source heat pump under low-temperature conditions during heating, improve the overall efficiency of the system, realize demand-side response of electricity, and greatly reduce costs.

[0006] According to one aspect of the present invention, there is provided a multi-class thermal energy unit energy storage interconnection system, including:

[0007] A first medium source thermal energy unit, a second medium source thermal energy unit, an energy storage unit, and an end device,

[0008] The first medium source heating unit, the second medium source heating unit, and the terminal equipment are connected in series in sequence through a water supply pipeline and a water return pipeline. The energy storage unit is connected in parallel between the water supply pipeline and the water return pipeline of the second medium source heating unit and the terminal equipment.

[0009] Wherein, a buffer unit is arranged on the water supply pipeline between the first medium source heating unit and the second medium source heating unit.

[0010] A bypass water supply pipeline and a bypass water return pipeline are configured between the first medium source heating unit and the terminal equipment.

[0011] This system further includes:

[0012] A first pump, a second pump, and a third pump.

[0013] Wherein, the first pump is arranged on the water supply pipeline of the second medium source heating unit connected to the buffer unit; the second pump is arranged on the water return pipeline of the second medium source heating unit connected to the terminal equipment; the third pump is arranged on the water supply pipeline of the terminal equipment connected to the second medium source heating unit.

[0014] The above-mentioned multi-type heating unit energy storage interconnection system further includes:

[0015] Valves, and the valves are arranged on the water supply pipeline and the water return pipeline between the second medium source heating unit and the terminal equipment.

[0016] For the above-mentioned multi-type heating unit energy storage interconnection system, in a possible implementation manner, a first valve is arranged on the water outlet pipeline of the second medium source heating unit connected to the energy storage unit, a second valve is arranged on the water outlet pipeline of the terminal equipment connected to the energy storage unit, and a third valve is arranged on the water supply pipeline between the third pump and the terminal equipment.

[0017] For the above-mentioned multi-type heating unit energy storage interconnection system, in a possible implementation manner, a fourth valve is arranged on the bypass water supply pipeline between the first medium source heating unit and the water inlet of the terminal equipment, and a fifth valve is arranged on the branch pipeline of the bypass water supply pipeline located between the first medium source heating unit and the third pump.

[0018] A sixth valve is arranged on the bypass water return pipeline between the water outlet of the terminal equipment and the first medium source heating unit, and a seventh valve is arranged on the branch pipeline of the bypass water return pipeline located between the water inlet of the terminal equipment and the first medium source heating unit.

[0019] An eighth valve is provided on the pipeline between the third pump and the water outlet of the terminal device.

[0020] For the above-mentioned multi-type thermal unit energy storage interconnection system, in a possible implementation manner, the valve is an electric valve.

[0021] For the above-mentioned multi-type thermal unit energy storage interconnection system, in a possible implementation manner, the energy storage unit is selected from a hot water storage tank, an energy storage water tank or a phase change energy storage device.

[0022] For the above-mentioned multi-type thermal unit energy storage interconnection system, in a possible implementation manner, the first medium source thermal unit is selected from an air source heat pump or a solar water heater.

[0023] For the above-mentioned multi-type thermal unit energy storage interconnection system, in a possible implementation manner, the second medium source thermal unit is a water source heat pump.

[0024] According to another aspect of the present invention, a control method for realizing automatic energy storage heating of a multi-type thermal unit energy storage interconnection system is provided, wherein the multi-type thermal unit energy storage interconnection system includes: a first medium source thermal unit, a second medium source thermal unit, an energy storage unit and a terminal device, and the method includes:

[0025] Judge the working condition of the multi-type thermal unit energy storage interconnection system;

[0026] According to the judged working condition, operate the conventional working mode, the low-temperature anti-freezing mode or the combined heating operation mode of the air source heat pump and the energy storage facility;

[0027] In the case of operating the conventional working mode, the first medium source thermal unit, the second medium source thermal unit and the energy storage unit operate jointly to provide heat;

[0028] In the case of operating the low-temperature anti-freezing mode, based on the predicted result of the freezing risk of the terminal device, determine whether to start the first medium source thermal unit and the energy storage unit to provide heat,

[0029] In the case of operating the combined heating operation mode of the air source heat pump and the energy storage facility, the first medium source thermal unit and the energy storage unit operate jointly to provide heat.

[0030] For the above-mentioned control method for automatic energy storage heating, in a possible implementation manner, in the conventional working mode, when the multi-type thermal unit energy storage interconnection system is in a low electricity price period, start the heat storage mode during the night valley electricity price period;

[0031] When the heat of the energy storage unit is sufficient, start the heat supply mode of the energy storage unit;

[0032] When the heat of the energy storage unit is insufficient, start the direct heating mode of the second medium source heating unit.

[0033] For the above control method of automatic energy storage heating, in a possible implementation manner, when starting the heat storage mode during the off-peak electricity price period at night, the water outlet of the first medium source heating unit is connected in sequence through a pipeline to the buffer unit, the first pump, the third pipeline, the primary side water inlet of the second medium source heating unit, the primary side water outlet of the second medium source heating unit, the fourth pipeline, and the water return port of the first medium source heating unit to form a first loop;

[0034] The secondary side water outlet of the second medium source heating unit is connected in sequence through a pipeline to the first valve, the fifth pipeline, the water inlet of the energy storage unit, the water outlet of the energy storage unit, the sixth pipeline, the second pump, and the secondary side water return port of the second medium source heating unit to form a second loop;

[0035] The secondary side water outlet of the second medium source heating unit is connected in sequence through a pipeline to the first valve, the seventh pipeline, the third pump, the third valve, the water inlet of the terminal device, the water outlet of the terminal device, the eighth pipeline, the second valve, the second pump, and the secondary side water return port of the second medium source heating unit to form a third loop.

[0036] When starting the heat supply mode of the energy storage unit, one end of the energy storage unit is connected in sequence to the fifth pipeline, the seventh pipeline, the third pump, the third valve, the terminal device, the eighth pipeline, the second valve, the sixth pipeline, and the other end of the energy storage unit to form a fourth loop.

[0037] When starting the direct heating mode of the second medium source heating unit, the secondary side water outlet of the second medium source heating unit is connected in sequence through a pipeline to the first valve, the seventh pipeline, the third pump, the third valve, the terminal device, the eighth pipeline, the second valve, the second pump, and the secondary side water return port of the second medium source heating unit to form a fifth loop.

[0038] For the above control method of automatic energy storage heating, in a possible implementation manner, in the low-temperature anti-freezing mode, when the water temperature of the terminal device is lower than the predetermined value, start the first medium source heating unit and the energy storage unit to provide heat;

[0039] When the water temperature of the terminal device is greater than or equal to the predetermined value, start the self-circulation of the terminal device.

[0040] For the above control method of automatic energy storage heating, in a possible implementation, when the water temperature of the terminal device is lower than the predetermined value, the water outlet of the first medium source heating unit is connected in sequence through a pipeline to the fourth valve, the first pipeline, the terminal device inlet pipe, the terminal device outlet pipe, the eighth pipeline, the second valve, the sixth pipeline, the fifth pipeline, the seventh pipeline, the third pump, the seventh valve, the second pipeline, and the water return port of the first medium source heating unit to form a sixth loop;

[0041] When the water temperature of the terminal device is greater than or equal to the predetermined value, one end of the terminal device is connected in sequence through a pipeline to the eighth pipeline, the eighth valve, the seventh pipeline, the third pump, the third valve, and the other end of the terminal device to form a seventh loop.

[0042] For the above control method of automatic energy storage heating, in a possible implementation, under the combined heating operation of the air source heat pump and the energy storage facility, the first medium source heating unit and the energy storage unit are started to provide heat.

[0043] For the above control method of automatic energy storage heating, in a possible implementation, under the combined heating operation of the air source heat pump and the energy storage facility, the water outlet of the first medium source heating unit is connected in sequence through a pipeline to the fourth valve, the first pipeline, the terminal device inlet pipe, the terminal device outlet pipe, the eighth pipeline, the second valve, the sixth pipeline, the fifth pipeline, the seventh pipeline, the third pump, the seventh valve, the second pipeline, and the water return port of the first medium source heating unit to form a sixth loop.

[0044] For the above control method of automatic energy storage heating, in a possible implementation, the system is switched between various working modes by controlling the opening and closing of the valves.

[0045] The technical solution provided by the present invention can achieve the following beneficial technical effects:

[0046] When the system of the present invention is working, the air source heat pump makes hot water at 10 - 35 degrees Celsius and stores it in the buffer water tank, and the water source heat pump makes hot water at 50 - 95 degrees Celsius from the buffer water tank and supplies it to the energy storage facility for storage. The energy storage facility can be an energy storage water tank, an energy storage water tank, a phase change energy storage device, or other suitable energy storage equipment. The energy storage facility can supply the terminal device at a suitable temperature through a heat exchange device and a terminal pipeline. The air source heat pump can also be replaced with other heating equipment such as a solar heater according to the actual situation.

[0047] Thus, the advantages of the three facilities, namely the air source heat pump, the water source heat pump, and the energy storage facility, are fully utilized. If the receiving end load requires heating during the day but not at night or intermittently, the actual load is jointly borne by the heat pump heating part and the energy storage part in the system. Through the coordinated control of energy storage and unit optimization, the power capacity expansion of the entire system can be reduced, thereby reducing investment, improving the low efficiency of the air source heat pump under cold conditions, and realizing the full utilization of electricity prices during low electricity price periods.

[0048] Other features and aspects of the present disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The drawings included in and constituting a part of the specification, together with the specification, illustrate exemplary embodiments, features, and aspects of the present disclosure and are used to explain the principles and inventive concepts of the present disclosure.

[0050] Figure 1 is a schematic diagram of the composition structure and pipeline connection of a multi-class thermal unit energy storage interconnection system shown according to an exemplary embodiment.

[0051] Figure 2 is a schematic diagram of the working pipeline link or the actual heat energy circulation link of a multi-class thermal unit energy storage interconnection system in a normal working mode shown according to an exemplary embodiment.

[0052] Figure 3 is a schematic diagram of the working pipeline link or the actual heat energy circulation link of a multi-class thermal unit energy storage interconnection system in a low-temperature anti-freeze working mode shown according to an exemplary embodiment.

[0053] Figure 4 is a schematic diagram of the working pipeline link or the actual heat energy circulation link of a multi-class thermal unit energy storage interconnection system in a combined heating operation mode of an air source heat pump and an energy storage facility shown according to an exemplary embodiment.

[0054] Note: In Figure 2-4 , solid lines represent the pipelines actually operating in the working state, and dashed lines represent the pipelines not operating in the working state. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0055] Various exemplary embodiments, features, and aspects of the present disclosure will be described in detail below with reference to the drawings. The same reference numerals in the drawings denote elements having the same or similar functions. Although various aspects of the embodiments are shown in the drawings, the drawings do not have to be drawn to scale unless otherwise specified.

[0056] As used herein, the term "exemplary" means "serving as an example, embodiment, or illustration". Any embodiment described herein as "exemplary" is not necessarily to be construed as superior or better than other embodiments.

[0057] In addition, for a better illustration of the present disclosure, numerous specific details are given in the following detailed description. Those skilled in the art should understand that the present disclosure can also be implemented without some of these specific details. In some instances, methods, means, elements, links, and connection relationships well known to those skilled in the art are not described in detail so as to highlight the gist of the present disclosure.

[0058] Figure 1 The composition structure and pipeline connection diagram of a multi-class thermal unit energy storage interconnection system are shown according to an exemplary embodiment.

[0059] As Figure 1 shown, the multi-class thermal unit energy storage interconnection system includes: an air source heat pump 1, a water source heat pump 5, an energy storage facility 9, and a terminal device 12. The air source heat pump 1, the water source heat pump 5, and the terminal device 12 are sequentially connected in series through a water supply pipeline and a return water pipeline, and the energy storage facility 9 is connected in parallel between the water supply pipeline and the return water pipeline of the water source heat pump 5 and the terminal device 12. Among them, a buffer water tank 2 is provided on the water supply pipeline between the air source heat pump 1 and the water source heat pump 5, and a bypass water supply pipeline I and a bypass return water pipeline II are configured between the air source heat pump 1 and the terminal device 12.

[0060] In a possible implementation manner, the water outlet pipe of the air source heat pump 1 is directly connected to the terminal device 12 through the bypass pipeline I, an electric valve 4 is provided on the bypass pipeline I, and the terminal device 12 returns to the return water pipe of the air source heat pump 1 through the pipeline II; the water outlet pipe of the air source heat pump 1 is connected to the buffer water tank 2, and is connected to the primary side water inlet of the water source heat pump 5 through the air source side water pump 3 on the pipeline III, and the primary side water outlet of the water source heat pump 5 is connected to the air source heat pump 1 through the pipeline return water pipe IV; an electric valve 10 is provided at the secondary side water outlet of the water source heat pump 5, the secondary side water outlet pipe of the water source heat pump 5 is connected to the water inlet of the energy storage facility 9 through the pipeline V, and the water outlet of the energy storage facility 9 returns to the secondary side water return port of the water source heat pump 5 through the pipeline VI through the water source side water pump 6; the secondary side water supply port of the water source heat pump 5 is connected to the terminal water pump 11 and the terminal device 12 through the pipeline VII, and the return water of the terminal device returns to the secondary side water return port of the water source heat pump 5 through the pipeline VIII; at the same time, the water inlet of the energy storage facility 9 is connected to the terminal water pump and the terminal device 12 through the pipeline V and the pipeline VII, and the return water of the terminal device returns to the water outlet of the energy storage facility through the pipeline VIII and the pipeline VI. An adjustment valve 8 is provided in the middle of the pipeline VII and the pipeline VIII to ensure an appropriate water supply temperature for the terminal device.

[0061] The air source heat pump unit is connected to the electric valve 4, and is connected to the terminal equipment through the pipeline I and the electric valve 13, and through the terminal water pump 11 and the electric valve 16. The water discharged from the terminal equipment 12 returns to the water inlet of the air source heat pump 1 through the electric valve 14 and the pipeline II, and circulates reciprocally.

[0062] In a possible implementation manner, the pipeline connection mode of the multi-type thermal unit energy storage interconnection system is as follows: the water outlet of the air source heat pump 1 - electric valve 4 - pipeline I - terminal water pump 11 - terminal system 12 - electric valve 14 - pipeline II - the water return port of the air source heat pump 1. The water outlet of the air source heat pump 1 - buffer water tank 2 - air source side water pump 3 - pipeline III - the primary side water inlet of the water source heat pump 5 - the primary side water outlet of the water source heat pump 5 - pipeline IV - the water return port of the air source heat pump 1. The secondary side water outlet of the water source heat pump 5 - electric valve 10 - pipeline V - the water inlet of the energy storage facility 9 - the water outlet of the energy storage facility 9 - pipeline VI - water source side water pump 6 - the secondary side water return port of the water source heat pump 5. The secondary side water outlet of the water source heat pump 5 - electric valve 10 - pipeline VII - terminal water pump 11 - terminal system 12 - pipeline VIII - electric valve 7 - water source side water pump 6 - the secondary side water return port of the water source heat pump 5. Pipeline VII - terminal water pump 11 - electric valve 16 - terminal system 12 - pipeline VIII - electric valve 8 - pipeline VII.

[0063] Optionally, the energy storage facility 9 includes but is not limited to a hot water storage tank, an energy storage water tank or a phase change energy storage device.

[0064] Optionally, the air source heat pump can also be replaced by a solar heater or other heating equipment.

[0065] In an embodiment of the present invention, a control method for realizing automatic energy storage heating of a multi-type thermal unit energy storage interconnection system is provided. Among them, the multi-type thermal unit energy storage interconnection system can be the multi-type thermal unit energy storage interconnection system in the above embodiment, and the method includes:

[0066] Judge the working condition of the multi-type thermal unit energy storage interconnection system;

[0067] According to the judged working condition, operate the conventional working mode, the low-temperature anti-freezing mode or the combined heating operation mode of the air source heat pump and the energy storage facility;

[0068] In the case of operating the conventional working mode, the first medium source thermal unit, the second medium source thermal unit and the energy storage unit operate jointly to provide heat;

[0069] In the case of operating the low-temperature anti-freezing mode, based on the freezing risk prediction result of the terminal equipment, determine whether to start the first medium source thermal unit and the energy storage unit to provide heat;

[0070] When operating in the combined heating operation mode of the air source heat pump and the energy storage facility, the first medium source heat unit and the energy storage unit operate jointly to provide heat.

[0071] The present invention includes at least three main working modes: (1) the conventional working mode, that is, the combined operation mode of the air source heat pump 1, the water source heat pump 5, and the energy storage facility 9; (2) the low-temperature anti-freezing working mode; (3) the combined working mode of the air source heat pump 1 and the energy storage facility 9. Using automatic control, they are respectively applied to different scenario requirements.

[0072] 1. Conventional working mode

[0073] Figure 2 The figure shows a schematic diagram of the working pipeline link or the actual heat energy circulation link of a multi-class heat unit energy storage interconnection system in the conventional working mode according to an exemplary embodiment.

[0074] In the conventional working mode, the air source heat pump 1, the water source heat pump 5, and the energy storage facility 9 operate jointly. This working mode is usually applicable to heating in cold winter periods. The working pipeline link is as Figure 3 shown.

[0075] In this conventional working mode, the specific link relationship of the working pipeline of the multi-class heat unit energy storage interconnection system is:

[0076] (1) The water outlet of the air source heat pump 1 - buffer water tank 2 - air source side water pump 3 - pipeline III - the primary side water inlet of the water source heat pump 5 - the primary side water outlet of the water source heat pump 5 - pipeline IV - the water return port of the air source heat pump 1.

[0077] (2) The secondary side water outlet of the water source heat pump 5 - electric valve 10 - pipeline V - the water inlet of the energy storage facility 9 - the water outlet of the energy storage facility 9 - pipeline VI - water source side water pump 6 - the secondary side water return port of the water source heat pump 5.

[0078] The terminal device 12 - pipeline VIII - electric valve 8 - pipeline VII - terminal water pump 11 - electric valve 16 - terminal device 12. This working condition is the heat storage mode of the system during the low valley electricity period at night.

[0079] (3) The secondary side water outlet of the water source heat pump 5 - electric valve 10 - pipeline VII - terminal water pump 11 - electric valve 16 - terminal device 12 - pipeline VIII - electric valve 7 - water source side water pump 6 - the secondary side water return port of the water source heat pump 5. This working condition is the direct heating mode of the water source heat pump.

[0080] (4) The energy storage facility 9 - pipeline V - pipeline VII - terminal water pump 11 - electric valve 16 - terminal device 12 - pipeline VIII - electric valve 7 - pipeline VI - energy storage facility 9. This working condition is the heating mode of the energy storage facility.

[0081] The working principle of this working mode is as follows: The air source heat pump 1 produces hot water at 10 - 35°C and stores it in the buffer water tank 2. The water source heat pump 5 uses the hot water in the buffer water tank 2 to heat it up to 50 - 95°C and supplies it to the energy storage facility 9 for storage. Thus, the energy storage temperature range of the energy storage facility 9 is greatly broadened, the energy storage capacity can be increased in a large range, and the volume can be significantly reduced, greatly improving the energy storage economy. For example, by adopting the air source heat pump, water source heat pump, and water heat storage method, the energy storage facility 9 can store hot water at 50 - 95°C, and the volume of the energy storage facility 9 is approximately one-fifth of that for storing hot water at 20°C under the same energy storage conditions. The energy storage method, volume, and layout can be reasonably designed according to the site conditions and system requirements to make full use of the electricity price during low electricity price periods. The energy storage facility 9 can supply the terminal equipment 12 at an appropriate temperature through the heat exchange device and the terminal pipeline, completely solving the problems that the outlet water temperature of the air source heat pump 1 is difficult to guarantee and it cannot drive radiators.

[0082] If the heat of the heat storage facility is insufficient, the direct heating mode of the water source heat pump equipment can be adopted to ensure the heating stability of the system with multiple heat sources.

[0083] 2. Low-temperature anti-freezing operation mode

[0084] Figure 3 It is a schematic diagram of the working pipeline link or the actual heat energy circulation link of a multi-class thermal unit energy storage interconnection system in the low-temperature anti-freezing working mode shown according to an exemplary embodiment.

[0085] During the periods when normal heating is not required at night or during holidays, the low-temperature anti-freezing operation mode can be adopted. In the state of the low-temperature anti-freezing operation mode, the air source heat pump 1 and the energy storage water tank operate jointly. The specific operation of this low-temperature anti-freezing operation mode can be divided into 2 modes:

[0086] Mode 1:

[0087] When the water temperature of the terminal equipment 12 meets the anti-freezing requirements, the system operates as Figure 3 shown:

[0088] The specific working pipeline of this working mode is: Terminal equipment 12 - Pipeline VIII - Electric valve 8 - Pipeline VII - Terminal water pump 11 - Electric valve 16 - Terminal equipment 12.

[0089] The working principle is: After the system stops running during the day, the residual temperature of the pipeline of the terminal equipment is still relatively high, and only the self-circulation of the terminal equipment 12 is required to meet the anti-freezing requirements.

[0090] Mode 2:

[0091] When the water temperature of the terminal equipment 12 is lower than the predetermined value, the system operation is as shown in Figure 3 shown:

[0092] The working pipeline is specifically as follows: the water outlet of the air source heat pump 1 - the electric valve 4 - Pipeline I - the water inlet pipe of the terminal device 12 - the water outlet pipe of the terminal device 12 - Pipeline VIII - the electric valve 7 - Pipeline VI - Pipeline V - Pipeline VII - the terminal water pump 11 - the electric valve 15 - Pipeline II - the water return port of the air source heat pump 1.

[0093] The working principle is: when there is a risk of freezing due to the relatively low water temperature of the terminal device 12 at night, the air source heat pump 1 starts to increase the pipeline temperature. At the same time, it operates jointly with the energy storage facility 9 to increase the water volume of the operating system, prevent the intermittent start of the air source heat pump 1 unit, and improve the system stability.

[0094] 3. Combined heating operation mode of air source heat pump and energy storage facility

[0095] Figure 4 The figure shows a schematic diagram of the working pipeline link or the actual heat energy circulation link of a multi - type thermal unit energy storage interconnection system in the combined heating operation mode of an air source heat pump and an energy storage facility according to an exemplary embodiment.

[0096] The combined heating working mode of the air source heat pump 1 and the energy storage facility 9 is applicable to the temporary shutdown or maintenance of the water source heat pump, or the period with relatively high outdoor temperature in the early winter and the end of winter seasons. For the schematic diagram of the working pipeline link in this working mode, please refer to Figure 4 .

[0097] In this mode, the working pipeline is specifically as follows: the water outlet of the air source heat pump 1 - the electric valve 4 - Pipeline I - the water inlet pipe of the terminal device 12 - the water outlet pipe of the terminal device 12 - Pipeline VIII - the electric valve 7 - Pipeline VI - Pipeline V - Pipeline VII - the terminal water pump 11 - the electric valve 15 - Pipeline II - the water return port of the air source heat pump 1.

[0098] The working principle of this working mode is: the air source heat pump 1 unit produces hot water at about 50 degrees and stores it in the energy storage facility 9. At the same time, it jointly supplies heat with the energy storage facility 9 to avoid frequent start - stop of the unit and reduce the energy consumption of the system operation.

[0099] In a possible implementation, the system is switched between different working modes by controlling the opening and closing of the valves.

[0100] Regarding the system composition structure, pipeline connection relationship, specific working mode, etc. in the above - mentioned embodiments, they have been described in detail in the embodiments of the relevant devices, and will not be elaborated here in detail.

[0101] The foregoing are only the preferred embodiments of the present invention and are not intended to limit the present invention. The above description is exemplary and not exhaustive, and is also not limited to the disclosed embodiments. Many modifications, equivalent substitutions, and changes are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, the practical application, or the improvement of the technology in the market, or to enable other ordinary technicians in the art to understand the embodiments disclosed herein.

Claims

1. A control method for realizing automatic energy storage heating in a multi-class thermal energy unit energy storage interconnection system, the system comprising: The first medium source heating unit, the second medium source heating unit, the energy storage unit and the terminal equipment. The first medium source heating unit, the second medium source heating unit and the terminal equipment are sequentially connected in series through the water supply pipeline and the return water pipeline. The energy storage unit is connected in parallel between the water supply pipeline and the return water pipeline of the second medium source heating unit and the terminal equipment. A buffer unit is arranged on the water supply pipeline between the first medium source heating unit and the second medium source heating unit. A bypass water supply pipeline and a bypass return water pipeline are configured between the first medium source heating unit and the terminal equipment. The system further includes: a first pump, a second pump and a third pump. The first pump is arranged on the water supply pipeline of the second medium source heating unit connected to the buffer unit. The second pump is arranged on the return water pipeline of the second medium source heating unit connected to the terminal equipment. The third pump is arranged on the water supply pipeline of the terminal equipment connected to the second medium source heating unit. Valves are arranged on the water supply pipeline and the return water pipeline between the second medium source heating unit and the terminal equipment. The method includes: Judging the working condition of the multi-type heat source energy storage interconnected system; According to the judged working condition, operating the conventional working mode, the low-temperature anti-freezing mode or the combined heating operation mode of the air source heat pump and the energy storage facility; In the case of operating the conventional working mode, the first medium source heating unit, the second medium source heating unit and the energy storage unit operate jointly to provide heat; In the case of operating the low-temperature anti-freezing mode, based on the freezing risk prediction result of the terminal equipment, determining whether to start the first medium source heating unit and the energy storage unit to provide heat; In the case of operating the combined heating operation mode of the air source heat pump and the energy storage facility, the first medium source heating unit and the energy storage unit operate jointly to provide heat; The system is switched between various working modes by controlling the opening and closing of each valve.

2. The control method for automatic energy storage heating according to claim 1, characterized in that, Wherein, In the conventional working mode, when the multi-type heat source energy storage interconnected system is in the low electricity price period, start the heat storage mode during the night valley electricity price period; When the heat of the energy storage unit is sufficient, start the heat supply mode of the energy storage unit; When the heat of the energy storage unit is insufficient, start the direct heat supply mode of the second medium source heating unit.

3. The control method for automatic energy storage heating according to claim 1, characterized in that, Wherein, In the case of starting the heat storage mode during the night valley electricity price period, the water outlet of the first medium source heating unit is sequentially connected through pipelines to the buffer unit, the first pump, the third pipeline, the primary side water inlet of the second medium source heating unit, the primary side water outlet of the second medium source heating unit, the fourth pipeline and the water return port of the first medium source heating unit to form a first loop; The secondary side water outlet of the second medium source heating unit is sequentially connected through pipelines to the first valve, the fifth pipeline, the water inlet of the energy storage unit, the water outlet of the energy storage unit, the sixth pipeline, the second pump and the secondary side water return port of the second medium source heating unit to form a second loop; The secondary side water outlet of the second medium source heating unit is sequentially connected through pipelines to the first valve, the seventh pipeline, the third pump, the third valve, the water inlet of the terminal equipment, the water outlet of the terminal equipment, the eighth pipeline, the second valve, the second pump and the secondary side water return port of the second medium source heating unit to form a third loop; When the heat storage unit heating mode is started, one end of the heat storage unit is sequentially connected to the fifth pipeline, the seventh pipeline, the third pump, the third valve, the terminal device, the eighth pipeline, the second valve, the sixth pipeline, and the other end of the heat storage unit to form a fourth loop; When the direct heating mode of the second medium source heating unit is started, the secondary side outlet of the second medium source heating unit is sequentially connected to the first valve, the seventh pipeline, the third pump, the third valve, the terminal device, the eighth pipeline, the second valve, the second pump, and the secondary side return port of the second medium source heating unit through the pipeline to form a fifth loop; When the water temperature of the terminal device is lower than the predetermined value, the outlet of the first medium source heating unit is sequentially connected to the fourth valve, the first pipeline, the inlet pipe of the terminal device, the outlet pipe of the terminal device, the eighth pipeline, the second valve, the sixth pipeline, the fifth pipeline, the seventh pipeline, the third pump, the seventh valve, the second pipeline, and the return port of the first medium source heating unit through the pipeline to form a sixth loop; When the water temperature of the terminal device is greater than or equal to the predetermined value, one end of the terminal device is sequentially connected to the eighth pipeline, the eighth valve, the seventh pipeline, the third pump, the third valve, and the other end of the terminal device through the pipeline to form a seventh loop.

4. The control method of automatic energy storage heating according to claim 1, characterized in that In the low-temperature anti-freezing mode, when the water temperature of the terminal device is lower than the predetermined value, the first medium source heating unit and the heat storage unit are started to provide heat; When the water temperature of the terminal device is greater than or equal to the predetermined value, the self-circulation of the terminal device is started.

5. The control method of automatic energy storage heating according to claim 1, characterized in that In the combined heating operation mode of the first medium source heating unit and the energy storage facility, the first medium source heating unit and the heat storage unit are started to provide heat.

6. The control method of automatic energy storage heating according to claim 1, characterized in that A first valve is provided on the outlet pipeline of the second medium source heating unit connected to the heat storage unit, a second valve is provided on the outlet pipeline of the terminal device connected to the heat storage unit, and a third valve is provided on the water supply pipeline between the third pump and the terminal device.

7. The control method of automatic energy storage heating according to claim 1, characterized in that A fourth valve is provided on the bypass water supply pipeline between the first medium source heating unit and the inlet of the terminal device, and a fifth valve is provided on the branch pipeline of the bypass water supply pipeline between the first medium source heating unit and the third pump, A sixth valve is provided on the bypass return water pipeline between the outlet of the terminal device and the first medium source heating unit, and a seventh valve is provided on the branch pipeline of the bypass return water pipeline between the inlet of the terminal device and the first medium source heating unit, An eighth valve is provided on the pipeline between the third pump and the outlet of the terminal device.

8. The control method for automatic energy storage heating according to claim 1, wherein, The valve is an electric valve.

9. The control method of automatic energy storage heating according to claim 1, characterized in that The heat storage unit is selected from a hot water storage tank, an energy storage water tank or a phase change energy storage device; The first medium source thermal unit is selected from an air source heat pump or a solar heater; The second medium source thermal unit is a water source heat pump.

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