Design and operation method of energy storage type multi-source flexible heat pump air conditioning system
Through hourly load calculation and equipment selection optimization, combined with peak and valley electricity price policies, a storage-type multi-source flexible heat pump air-conditioning system was designed. This solved the problem that the existing technology did not fully consider the energy storage potential and electricity price policies, and achieved system performance optimization and cost reduction.
Patent Information
- Application Number
- CN202510950288.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-10
- Publication Date
- 2025-09-05
AI Technical Summary
The design of existing heat pump air-conditioning systems does not fully consider the energy storage potential of buildings, the energy storage potential of the heat exchange medium of heat pump air-conditioning systems, and the impact of peak and valley electricity price policies on equipment selection, resulting in the failure to fully optimize system performance.
Hourly air conditioning cooling and heating load calculations are used to quantify the energy storage potential of buildings and heat exchange media. Combined with local peak-valley electricity price policies, an energy storage-type multi-source flexible heat pump air conditioning system is designed. Through hourly load characteristic analysis and equipment selection optimization, an operation strategy is formulated to reduce the system's initial investment and operating costs.
It optimizes the performance of the heat pump air-conditioning system, reduces initial investment and operating costs, reduces host operation during peak electricity price periods, and helps stabilize the operation of the power grid.
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Figure CN120593355A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of heat pump air conditioning, and in particular to a design and operation method of an energy storage type multi-source flexible heat pump air conditioning system. Background Art
[0002] With rapid socioeconomic development, the energy crisis has become a major global concern. Energy-saving technologies and green buildings have become key trends in contemporary social development. Among the many energy-saving and emission-reduction technologies, heat pump air conditioning systems, with their high efficiency and energy-saving features, have garnered significant attention. Current heat pump air conditioning system designs typically use the maximum cooling and heating loads over a typical day (24 hours) to select the main unit and other equipment. Hourly cooling and heating loads throughout the year are rarely used to select the main unit and other equipment. These systems fail to quantify and consider the impact of the building's energy storage potential and the heat exchange medium's energy storage potential on the selection of the main unit and other equipment. They also fail to quantify and consider the impact of peak and off-peak electricity pricing policies on the selection of the main unit and other equipment. They also fail to explore the system's flexibility potential and consider the system's operational characteristics. If these factors can be properly quantified, the performance of heat pump air conditioning systems will be further optimized. Summary of the Invention
[0003] In order to solve the above problems, the present invention provides a design method for an energy storage type multi-source flexible heat pump air conditioning system, and also provides an operation method for an energy storage type multi-source flexible heat pump air conditioning system. Specifically, the following technical solutions can be adopted: The design method of the energy storage multi-source flexible heat pump air conditioning system of the present invention comprises the following steps: S1, hourly calculation of air conditioning cooling load and heating load: First, determine all the individual buildings covered by the heat pump air conditioning system, and determine the indoor set temperature, relative humidity, cooling cycle, heating cycle, and daily operating time. Then, calculate the hourly total cooling load L of the heat pump air conditioning system during a cooling cycle according to formula (1): 总冷i , and determine the maximum cooling load L of the heat pump air conditioning system 总冷max ; Calculate the total hourly heat load L of the heat pump air conditioning system during a heating cycle according to formula (2): 总热i , and determine the maximum heat load L of the heat pump air conditioning system 总热max ; The above formula (1) is: Formula (2) is: Among them, L 冷i ——Cooling load of the jth building at the i-th hour, kW; L 热i ——heat load of the jth building at the i-th hour, kW; aj ——the heat gain unevenness coefficient of the heat source in the jth building; b——simultaneous use coefficient of each single building; m——the total number of buildings included in the air-conditioning user end; S2, hourly analysis of cooling load and heating load characteristics of air conditioning: With the maximum cooling load L 总冷max The load rate interval is divided into 70% to 80%, 80% to 90%, and 90% to 100%, and the total cooling load L per hour in a cooling cycle is counted daily. 总冷i The cumulative duration in each of the above load rate intervals, and the maximum daily cumulative duration in each load rate interval are recorded as T1′, T2′, and T3′ respectively; With maximum heat load L 总热max The load rate interval is divided into 70% to 80%, 80% to 90%, and 90% to 100%, and the total heat load L per hour in a heating cycle is counted daily. 总热i The cumulative duration within each of the above load rate intervals, and the maximum daily cumulative duration within each load rate interval are recorded as T1", T2", and T3" respectively; Then, the daily cumulative duration of the heat pump air conditioning system in the three load rate ranges of 70% to 80%, 80% to 90%, and 90% to 100% are: T1=max(T1′, T1″), T2=max(T2′, T2″), T3=max(T3′, T3″); S3, quantifying the energy storage potential of buildings: During cooling, at the calculated outdoor temperature, calculate the duration for the indoor temperature of each building to naturally rise from 26°C to 28°C and take the average value, recorded as t1. During heating, at the calculated outdoor temperature, calculate the duration for the indoor temperature of each building to naturally drop from 20°C to 18°C and take the average value, recorded as t2. The minimum energy storage potential of the building is T4 = min(t1, t2). S4. Quantify the energy storage potential of heat exchange media in heat pump air conditioning systems: During cooling, at the calculated outdoor temperature, with the unit turned off and the user-side circulating water pump turned on, calculate the duration t3 for the water supply temperature to rise from 7°C to 12°C. During heating, at the calculated outdoor temperature, with the unit turned off and the user-side circulating water pump turned on, calculate the duration t4 for the water supply temperature to drop from 45°C to 40°C. Therefore, the minimum energy storage potential of the heat exchange medium of the heat pump air conditioning system is T5 = min(t3, t4). S5, analyze local peak and valley electricity prices: Based on the local peak and valley electricity price policy, determine the maximum daily operating time T6 of the heat pump air conditioning system during the high electricity price period; S6, determine the energy supply capacity of the energy station: If T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =L 总冷max ×90%, while L 热 =L 总热max ×90%; if T2+T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =L 总冷max ×80%, while L 热 =L 总热max ×80%; if T1+T2+T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =L 总冷max ×70%, while L 热 =L 总热max ×70%; S7, determine the effective volume of the energy storage facility: If T4+T5>T6, the heat pump air conditioning system does not need to be equipped with energy storage facilities; if T4+T5<T6, the heat pump air conditioning system needs to be equipped with energy storage facilities, and the continuous energy supply time of the energy storage facilities is T6-(T4+T5); S8: Select equipment and complete the design according to the energy supply capacity of the energy station and the energy storage facility.
[0004] Preferably, in step five, when the electricity price periods are divided into peak, high, flat and low periods, the cumulative operating time t5 of the heat pump air-conditioning system in the peak electricity price period and the cumulative operating time t6 in the peak electricity price period are counted on a daily basis. If the peak electricity price period and the peak electricity price period are not continuous, the daily operating time T6′ of the heat pump air-conditioning system in the high electricity price period is equal to max(t5, t6), and the maximum value of T6′ is taken as the maximum daily operating time T6 of the heat pump air-conditioning system in the high electricity price period; if the peak electricity price period and the peak electricity price period are continuous, the maximum continuous operating time T6′ of the heat pump air-conditioning system in the high electricity price period is equal to t5+t6, and the maximum value of T6′ is taken as the maximum daily operating time T6 of the heat pump air-conditioning system in the high electricity price period.
[0005] Preferably, the energy storage facility uses water as the energy storage medium, and the effective volume V of the energy storage facility is calculated according to formula (3): C , V C =3600×L 总max ×[T6-(T4+T5)] / (k×c×ρ×|t h -t g | ) (3) Among them, V C ——Effective volume of energy storage facilities, m 3 ; L 总max——The larger of the maximum cooling load and the maximum heating load of the heat pump air-conditioning system, in kW; k is the ratio of the output of the energy storage facility in one storage-release cycle to the theoretically available energy, ranging from 0.85 to 0.9; c——specific heat capacity of water, kJ / (kg·℃); ρ——density of water, kg / m 3 ; t h ——Return water temperature setting value, °C; t g ——Water supply temperature setting value, °C; Preferably, the step eight includes the selection of the energy station host and auxiliary equipment.
[0006] Preferably, the selection of auxiliary equipment includes the selection of user-side circulating water pumps, ground-source circulating water pumps, energy storage circulating water pumps, energy storage equipment, and constant-pressure water replenishment equipment.
[0007] The energy storage multi-source flexible heat pump air conditioning system operation method of the present invention formulates an operation strategy based on a daily cycle according to the local peak and valley electricity price policy, including: During off-peak electricity price periods, the energy station host and corresponding circulating water pumps are turned on to supply cooling and heating to the buildings, while also storing cold or heat in the energy storage facilities; During the flat electricity price period, the energy station host and the corresponding circulating water pumps are turned on to supply cooling and heating to the buildings; During peak electricity prices or peak electricity price periods, the energy station host will be shut down first, and only the circulating water pump corresponding to the host will be turned on to supply cooling and heating to the building; when the return water temperature reaches the designed return water temperature, the circulating water pump corresponding to the energy storage facility will be turned on to supply cooling and heating to the building.
[0008] Preferably, during the off-peak electricity price period and the flat electricity price period, the indoor temperature during cooling is maintained at 24℃~26℃, and the indoor temperature during heating is maintained at 20℃~22℃; during the peak or spike electricity price period, the indoor temperature during cooling naturally rises from 26℃ to 28℃ and then is continuously maintained, and the indoor temperature during heating naturally drops from 20℃ to 18℃ and then is continuously maintained.
[0009] The present invention breaks the original design pattern and avoids the disadvantages of selecting the maximum values of the typical daily air-conditioning cooling load and heating load for the main unit and other equipment selection. In the design stage, the synergistic relationship between the system and the power grid is considered. Based on the peak-valley electricity price policy, the heat gain unevenness coefficient of the internal heat source of a single building and the simultaneous use coefficient of the building group are considered, the air-conditioning cooling load and heating load are calculated hourly, and corresponding strategies are designed to analyze the air-conditioning cooling load and heating load characteristics hourly, and at the same time, the energy storage potential of the building and the energy storage potential of the water capacity of the heat pump air-conditioning system are quantified, thereby tapping the system's flexible potential, reducing the capacity of the energy station main unit and other equipment selection, and achieving a reduction in the initial investment amount; in the operation stage, according to the peak-valley electricity price policy, a reasonable operation mode is formulated to reduce the system operation cost and achieve the purpose of energy saving; at the same time, the air-conditioning system minimizes the start-up of the main unit during peak electricity price or peak electricity price periods. In this way, the power grid load is reduced, and the stable operation of the power grid is actively contributed. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 It is a schematic diagram of the design process of the energy storage multi-source flexible heat pump air conditioning system described in the present invention. DETAILED DESCRIPTION
[0011] The following describes an embodiment of the present invention in detail with reference to the accompanying drawings. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process. However, the protection scope of the present invention is not limited to the following embodiment.
[0012] like Figure 1 As shown, the energy storage type multi-source flexible heat pump air conditioning system design of the present invention includes the following steps: S1, hourly calculation of air conditioning cooling load and heating load: First, determine all the individual buildings covered by the heat pump air conditioning system, and determine the indoor set temperature, relative humidity (the indoor design temperature for cooling in summer is 26±2℃, the relative humidity ≤70%, and the indoor design temperature for heating in winter is 20±2℃, and the relative humidity is not controlled), as well as the cooling cycle (for example, May 15th to September 30th), the heating cycle (for example, November 15th to March 15th of the following year), and the daily operating hours (for example, the operating hours of some buildings are 8:00 to 18:00, and the operating hours of other buildings are 24 hours a day). Then, calculate the hourly total cooling load L of the heat pump air conditioning system during a cooling cycle according to formula (1): 总冷i , and determine the maximum cooling load L of the heat pump air conditioning system 总冷max ; Calculate the total hourly heat load L of the heat pump air conditioning system during a heating cycle according to formula (2): 总热i , and determine the maximum heat load L of the heat pump air conditioning system 总热max ; The above formula (1) is: Formula (2) is: Among them, L 冷i ——Cooling load of the jth building at the i-th hour, kW; L 热i ——heat load of the jth building at the i-th hour, kW; a j ——the heat gain unevenness coefficient of the heat source in the jth building; b——simultaneous use coefficient of each single building; m——the total number of buildings included in the air-conditioning user end; S2, hourly analysis of cooling load and heating load characteristics of air conditioning: With the maximum cooling load L 总冷max The load rate interval is divided into 70% to 80%, 80% to 90%, and 90% to 100%, and the total cooling load L per hour in a cooling cycle is counted daily. 总冷i The cumulative duration in each of the above load rate intervals, and the maximum daily cumulative duration in each load rate interval are recorded as T1′, T2′, and T3′ respectively; With maximum heat load L 总热max The load rate interval is divided into 70% to 80%, 80% to 90%, and 90% to 100%, and the total heat load L per hour in a heating cycle is counted daily. 总热i The cumulative duration within each of the above load rate intervals, and the maximum daily cumulative duration within each load rate interval are recorded as T1", T2", and T3" respectively; Then, the daily cumulative duration of the heat pump air conditioning system in the three load rate ranges of 70% to 80%, 80% to 90%, and 90% to 100% are: T1=max(T1′, T1″), T2=max(T2′, T2″), T3=max(T3′, T3″); For example, for a heat pump air conditioning system with a cooling period of May 15 to September 30 and running all day, the total hourly cooling load L 总冷i 139×24 data are obtained; according to the maximum cooling load L 总冷max 70% to 80%, 80% to 90%, 90% to 100% of the total cooling load L per day 总冷i When the cumulative time in each of the above load rate intervals is calculated, 139×3 data are obtained; then, the maximum value of the 139 data in the load rate interval of 70% to 80% is obtained to obtain T1′; the maximum value of the 139 data in the load rate interval of 80% to 90% is obtained to obtain T2′; the maximum value of the 139 data in the load rate interval of 90% to 100% is obtained to obtain T3′.
[0013] According to this method, the maximum daily cumulative duration T1″, T2″, and T3″ in each load rate range of the heating cycle are calculated.
[0014] Afterwards, compare the values of T1′ and T1″, T2′ and T2″, and T3′ and T3″ to obtain T1, T2, and T3.
[0015] S3, quantifying the energy storage potential of buildings: When cooling, calculate the duration for the indoor temperature of each building to naturally rise from 26°C to 28°C at the calculated outdoor temperature. And take the average value, record it as t1; when heating, at the outdoor calculated temperature, calculate the duration of each building's indoor temperature naturally dropping from 20℃ to 18℃ according to formula (3): And take the average value, record it as t2; then the minimum energy storage potential of the building is T4=min(t1, t2); above Calculate according to the following formula: in, ——The duration of time for the indoor temperature of the jth building to naturally rise from 26℃ to 28℃ or naturally drop from 20℃ to 18℃ at the outdoor calculated temperature, in hours; C j ——total heat capacity of the jth building, kJ / ℃; θ2——When cooling, take 28; when heating, take 20; ℃; θ1——When cooling, take 26; when heating, take 18;℃; L maxj ——the maximum hourly cooling load or the maximum hourly heating load of the j-th building, kW; S4. Quantify the energy storage potential of heat exchange media in heat pump air conditioning systems: During cooling, at the calculated outdoor temperature, with the unit turned off and the user-side circulating water pump turned on, calculate the duration t3 for the water supply temperature to rise from 7°C to 12°C. During heating, at the calculated outdoor temperature, with the unit turned off and the user-side circulating water pump turned on, calculate the duration t4 for the water supply temperature to drop from 45°C to 40°C. Therefore, the minimum energy storage potential of the heat exchange medium of the heat pump air conditioning system is T5 = min(t3, t4). The above t3 and t4 are calculated according to the following formula: Wherein, t3 is the duration for the water supply temperature to rise from 7°C to 12°C under the outdoor calculated temperature during cooling, assuming the unit is shut down and the user-side circulating water pump is turned on, in hours; t4 - During heating, at the calculated outdoor temperature, with the unit turned off and the user-side circulating water pump turned on, the duration for the water supply temperature to rise from 45°C to 40°C, in hours; c——Specific heat capacity of the heat exchange medium of the air conditioning system, kJ / (kg·℃); ρ——density of heat exchange medium in air conditioning system, kg / m 3 ; V——the volume of heat exchange medium in air conditioning system, m 3 ; θ2——When cooling, take 12; when heating, take 45;℃; θ1——When cooling, take 7; when heating, take 40;℃; L 总max ——The maximum hourly cooling load or the maximum hourly heating load of all buildings at the air-conditioning user end, kW; S5, analyze local peak and valley electricity prices: Based on the local peak and valley electricity price policy, determine the maximum daily operating time T6 of the heat pump air conditioning system during the high electricity price period; If the local peak-valley electricity price policy divides the electricity price period into peak, flat and valley periods, first count the cumulative operating time t6 of the heat pump air conditioning system during the peak electricity price period on a daily basis, then compare this set of data and select the maximum value as the maximum daily operating time T6 of the heat pump air conditioning system during the high electricity price period; If the local peak-valley electricity price policy is to divide the electricity price periods into peak, high, flat and valley periods, the cumulative operating time t5 of the heat pump air-conditioning system in the peak electricity price period and the cumulative operating time t6 in the peak electricity price period shall be counted on a daily basis. If the peak electricity price period and the peak electricity price period are not continuous, the daily operating time T6′ of the heat pump air-conditioning system in the high electricity price period shall be equal to max(t5, t6), and the maximum value of T6′ shall be taken as the maximum daily operating time T6 of the heat pump air-conditioning system in the high electricity price period; if the peak electricity price period and the peak electricity price period are continuous, the maximum continuous operating time T6′ of the heat pump air-conditioning system in the high electricity price period shall be equal to t5+t6, and the maximum value of T6′ shall be taken as the maximum daily operating time T6 of the heat pump air-conditioning system in the high electricity price period.
[0016] S6, determine the energy supply capacity of the energy station: If T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =L 总冷max ×90%, while L 热 =L 总热max ×90%; if T2+T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =L 总冷max ×80%, while L 热 =L 总热max×80%; if T1+T2+T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =L 总冷max ×70%, while L 热 =L 总热max ×70%; S7, determine the effective volume of the energy storage facility: If T4+T5>T6, the heat pump air conditioning system does not need to be equipped with energy storage facilities; if T4+T5<T6, the heat pump air conditioning system needs to be equipped with energy storage facilities, and the continuous energy supply time of the energy storage facilities is T6-(T4+T5); Preferably, when the energy storage facility uses water as the energy storage medium, the effective volume V of the energy storage facility is calculated according to formula (3): C , V C =3600×L 总max ×[T6-(T4+T5)] / (k×c×ρ×|t h -t g | ) (3) Among them, V C ——Effective volume of energy storage facilities, m 3 ; L 总max ——The larger of the maximum cooling load and the maximum heating load of the heat pump air-conditioning system, in kW; k is the ratio of the output of the energy storage facility in one storage-release cycle to the theoretically available energy, which can be taken as 0.85 to 0.9; c——specific heat capacity of water, kJ / (kg·℃); ρ——density of water, kg / m 3 ; t h ——Return water temperature setting value, °C; t g ——Water supply temperature setting value, °C; S8. Select equipment according to the energy supply capacity of the energy station and the energy storage facility, including the selection of the main unit of the energy station and the selection of auxiliary equipment.
[0017] For example, when the energy station host includes a ground source heat pump unit and an air source heat pump unit, and when L 冷 >L 热 When the heat load L is borne by the ground source heat pump unit, on the basis of ensuring the soil thermal balance, 热地 = L 热 ×70%, the heat load L borne by the air source heat pump unit 热空 =L 热 -L 热地 ; At the same time, ensure the cooling capacity of the ground source heat pump unit L冷地 Cooling capacity L of air source heat pump 冷空 The sum satisfies the energy supply capacity L of the source station 冷 .
[0018] The selection of the above-mentioned auxiliary equipment includes the selection of user-side circulating water pumps, ground-source circulating water pumps, energy storage circulating water pumps, energy storage equipment, and constant pressure water replenishment equipment.
[0019] The operation method of the energy storage type multi-source flexible heat pump air-conditioning system described in the present invention formulates an operation strategy based on the local peak and valley electricity price policy on a daily basis, including: during the valley electricity price period, the energy station host and the corresponding circulating water pump are turned on to supply cooling and heating to the building, and at the same time, cold or heat is stored in the energy storage facility; during the flat electricity price period, the energy station host and the corresponding circulating water pump are turned on to supply cooling and heating to the building; during the peak electricity price or peak electricity price period, the energy station host is turned off first, and only the circulating water pump corresponding to the host is turned on to supply cooling and heating to the building; when the return water temperature reaches the designed return water temperature, the circulating water pump corresponding to the energy storage facility is turned on to supply cooling and heating to the building.
[0020] During the above-mentioned off-peak electricity price periods and flat electricity price periods, the indoor temperature during cooling is maintained at 24℃~26℃, and the indoor temperature during heating is maintained at 20℃~22℃; during peak or peak electricity price periods, the indoor temperature during cooling will naturally rise from 26℃ to 28℃ and then be continuously maintained, and the indoor temperature during heating will naturally drop from 20℃ to 18℃ and then be continuously maintained.
[0021] Compared with the traditional typical day design method, the annual hourly load design method described in the present invention has obvious advantages in terms of initial investment and operating costs of heat pump air-conditioning systems. The following is a detailed explanation using a certain park as an example.
[0022] A certain park consists of 1 research building, 1 dormitory, and 1 restaurant, with a total above-ground building area of 27101m 2 、4965m 2 、2896m 2 The total above-ground building area is 34,962 m 2 A vertical buried ground source heat pump and an air source heat pump are used for cooling and heating. The indoor design temperature for cooling is 26±2°C, and the indoor design temperature for heating is 20±2°C.
[0023] The hourly maximum cooling load and hourly maximum heating load calculated by the method of the present invention and the traditional typical day design method are shown in Table 1.
[0024] Table 1 Hourly maximum cooling load and hourly maximum heating load of the two methods The hourly air conditioning cooling load and heating load characteristics throughout the year are detailed in Table 2.
[0025] Table 2 Hourly cooling and heating load characteristics of air conditioners throughout the year The energy storage potential of buildings is detailed in Table 3. The minimum energy storage potential of a building is T4 = 0.9h.
[0026] Table 3 Energy storage potential of buildings Quantifying the energy storage potential of heat exchange media in heat pump air conditioning systems: When cooling, t3=0.6h; when heating, t4=0.7h; then the minimum energy storage potential of the heat exchange medium of the heat pump air-conditioning system is T5=0.6h.
[0027] The peak and off-peak electricity price periods in a certain region are as follows: peak hours are 9:00-12:00 and 18:00-21:00; flat hours are 7:00-9:00, 12:00-18:00, and 21:00-23:00; and off-peak hours are 23:00-7:00 the next day. Therefore, T6 = 3 hours.
[0028] Obviously, T2+T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =2786×80%=2228.8kW, while L 热 =2236×80%=1788.8kW.
[0029] The selection of main engine and energy storage facilities by the method of the present invention and the traditional typical day design method are detailed in Table 4, and the initial investment and operating costs are detailed in Table 5.
[0030] Table 4 Selection of host and energy storage facilities for the two methods Table 5 Initial investment and operating costs of the two methods It can be seen that compared with the traditional typical day design method, the method of the present invention saves 2.2 million yuan in initial investment in the main unit, reduces the main unit input power by 175.5kW and 181.5kW during heating and cooling respectively, and saves 650,000 yuan in annual operating costs.
[0031] It should be noted that, in the description of the present invention, terms indicating orientation or positional relationships such as “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “inside”, and “outside” are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
Claims
1. A design method for an energy storage multi-source flexible heat pump air conditioning system, characterized in that: The steps include: S1, hourly calculation of air conditioning cooling load and heating load: First, determine all the individual buildings covered by the heat pump air conditioning system, and determine the indoor set temperature, relative humidity, cooling cycle, heating cycle, and daily operating time. Then, calculate the hourly total cooling load L of the heat pump air conditioning system during a cooling cycle according to formula (1): 总冷i , and determine the maximum cooling load L of the heat pump air conditioning system 总冷max ; Calculate the total hourly heat load L of the heat pump air conditioning system during a heating cycle according to formula (2): 总热i , and determine the maximum heat load L of the heat pump air conditioning system 总热max ; The above formula (1) is: ; Formula (2) is: ; Among them, L 冷i ——Cooling load of the jth building at the i-th hour, kW; L 热i ——heat load of the jth building at the i-th hour, kW; a j ——the heat gain unevenness coefficient of the heat source in the jth building; b——simultaneous use coefficient of each single building; m——the total number of buildings included in the air-conditioning user end; S2, hourly analysis of cooling load and heating load characteristics of air conditioning: With the maximum cooling load L 总冷max The load rate interval is divided into 70% to 80%, 80% to 90%, and 90% to 100%, and the total cooling load L per hour in a cooling cycle is counted daily. 总冷i The cumulative duration in each of the above load rate intervals, and the maximum daily cumulative duration in each load rate interval are recorded as T1′, T2′, and T3′ respectively; With maximum heat load L 总热max The load rate interval is divided into 70% to 80%, 80% to 90%, and 90% to 100%, and the total heat load L per hour in a heating cycle is counted daily. 总热i The accumulated duration in each of the above load rate intervals, and the maximum value of the daily accumulated duration in each load rate interval is recorded as T1", T2", and T3" respectively; Then, the daily cumulative duration of the heat pump air conditioning system in the three load rate ranges of 70% to 80%, 80% to 90%, and 90% to 100% are: T1=max(T1′, T1″), T2=max(T2′, T2″), T3=max(T3′, T3″); S3, quantifying the energy storage potential of buildings: During cooling, at the calculated outdoor temperature, calculate the duration for the indoor temperature of each building to naturally rise from 26°C to 28°C and take the average value, recorded as t1. During heating, at the calculated outdoor temperature, calculate the duration for the indoor temperature of each building to naturally drop from 20°C to 18°C and take the average value, recorded as t2. The minimum energy storage potential of the building is T4 = min(t1, t2). S4. Quantify the energy storage potential of heat exchange media in heat pump air conditioning systems: During cooling, at the calculated outdoor temperature, with the unit turned off and the user-side circulating water pump turned on, calculate the duration t3 for the water supply temperature to rise from 7°C to 12°C. During heating, at the calculated outdoor temperature, with the unit turned off and the user-side circulating water pump turned on, calculate the duration t4 for the water supply temperature to drop from 45°C to 40°C. Therefore, the minimum energy storage potential of the heat exchange medium of the heat pump air conditioning system is T5 = min(t3, t4). S5, analyze local peak and valley electricity prices: Based on the local peak and valley electricity price policy, determine the maximum daily operating time T6 of the heat pump air conditioning system during the high electricity price period; S6, determine the energy supply capacity of the energy station: If T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =L 总冷max ×90%, while satisfying L 热 =L 总热max ×90%; if T2+T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =L 总冷max ×80%, while satisfying L 热 =L 总热max ×80%; if T1+T2+T3<T4+T5, determine the energy supply capacity L of the energy station 冷 =L 总冷max ×70%, while satisfying L 热 =L 总热max ×70%; S7, determine the effective volume of the energy storage facility: If T4+T5>T6, the heat pump air conditioning system does not need to be equipped with energy storage facilities; if T4+T5<T6, the heat pump air conditioning system needs to be equipped with energy storage facilities, and the continuous energy supply time of the energy storage facilities is T6-(T4+T5); S8: Select equipment and complete the design according to the energy supply capacity of the energy station and the energy storage facility.
2. The design method of the energy storage type multi-source flexible heat pump air conditioning system according to claim 1 is characterized in that: In step 5, when the electricity price period is divided into peak, high, flat and low periods, the cumulative operating time t5 of the heat pump air conditioning system in the peak electricity price period and the cumulative operating time t6 in the peak electricity price period are counted on a daily basis. If the peak electricity price period and the peak electricity price period are not consecutive, the daily operating time T6′ of the heat pump air conditioning system in the high electricity price period is equal to max(t5, t6), and the maximum value of T6′ is taken as the maximum daily operating time T6 of the heat pump air conditioning system in the high electricity price period; If the peak electricity price period and the peak electricity price period are consecutive, the maximum continuous operation time of the heat pump air-conditioning system in the high electricity price period is T6′= t5+t6, and the maximum value of T6′ is taken as the maximum daily operation time T6 of the heat pump air-conditioning system in the high electricity price period.
3. The design method of the energy storage type multi-source flexible heat pump air conditioning system according to claim 1 is characterized in that: The energy storage facility uses water as the energy storage medium. The effective volume V of the energy storage facility is calculated according to formula (3): C , V C =3600×L 总max ×[T6-(T4+T5)] / (k×c×ρ×|t h -t g | ) (3) Among them, V C ——Effective volume of energy storage facilities, m 3 ; L 总max ——The larger of the maximum cooling load and the maximum heating load of the heat pump air-conditioning system, in kW; k is the ratio of the output of the energy storage facility in one storage-release cycle to the theoretically available energy, ranging from 0.85 to 0.9; c——specific heat capacity of water, kJ / (kg·℃); ρ——density of water, kg / m 3 ; t h ——Return water temperature setting value, °C; t g ——Water supply temperature setting value, ℃.
4. The design method of an energy storage multi-source flexible heat pump air conditioning system according to claim 1, characterized in that: The step eight includes the selection of the energy station host and auxiliary equipment.
5. The design method of the energy storage type multi-source flexible heat pump air conditioning system according to claim 4 is characterized in that: The selection of auxiliary equipment includes the selection of user-side circulating water pumps, ground-source circulating water pumps, energy storage circulating water pumps, energy storage equipment, and constant pressure water replenishment equipment.
6. The method for operating an energy storage multi-source flexible heat pump air conditioning system according to any one of claims 1 to 5, characterized in that: According to the local peak and valley electricity price policy, an operation strategy is formulated on a daily basis, including: During off-peak electricity price periods, the energy station host and corresponding circulating water pumps are turned on to supply cooling and heating to the buildings, while also storing cold or heat in the energy storage facilities; During the flat electricity price period, the energy station host and the corresponding circulating water pumps are turned on to supply cooling and heating to the buildings; During peak electricity prices or peak electricity price periods, the energy station host will be shut down first, and only the circulating water pump corresponding to the host will be turned on to supply cooling and heating to the building; when the return water temperature reaches the designed return water temperature, the circulating water pump corresponding to the energy storage facility will be turned on to supply cooling and heating to the building.
7. The method for operating an energy storage type multi-source flexible heat pump air conditioning system according to claim 6, characterized in that: During the off-peak electricity price period and the flat electricity price period, the indoor temperature during cooling is maintained at 24℃~26℃, and the indoor temperature during heating is maintained at 20℃~22℃; during the peak or sharp electricity price period, the indoor temperature during cooling naturally rises from 26℃ to 28℃ and then is continuously maintained, and the indoor temperature during heating naturally drops from 20℃ to 18℃ and then is continuously maintained.