An energy-saving based air conditioning system and control method

Abstract

The application relates to an energy-saving-based air conditioning system and a control method; the control method comprises the following steps: obtaining a target temperature and weather forecast data, predicting an air conditioning load through a building operation condition database; obtaining a current energy storage amount of an energy storage unit, predicting a preprocessing time of the energy storage unit through an energy storage unit preprocessing database; operating the air conditioning system according to the predicted air conditioning load, and storing extra energy generated during the operation of the air conditioning system into the energy storage unit; and according to the predicted preprocessing time of the energy storage unit, the energy storage unit pre-processes each area in the building through a water distributor. Through the use of the energy storage unit, the energy storage unit can be used to supply cooling and heating to each area during the power peak period or the electricity price peak period, the power supply efficiency of the urban or regional power grid can be obviously improved, the power peak can be transferred, the power grid load can be balanced, and the air conditioning operation cost can be saved.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and in particular to an energy-saving air conditioning system and control method. Background Technology

[0002] Large-scale central air conditioning systems are typically designed with multiple chiller units based on load calculations and building type. The number of chiller units activated depends on the load demand at the terminal terminals of the air conditioning system. Generally, the peak COP of commonly used screw chillers is between 60% and 90% of their rated load rate; the peak COP of centrifugal chillers is between 80% and 90% of their rated load rate. In particular, the COP value of centrifugal chillers decreases significantly when the load rate decreases.

[0003] When designing central air conditioning systems for large public buildings, air conditioning load calculations are required, and the selection of chiller units for the air conditioning system is generally based on these calculations. These load calculations use the summer outdoor dry-bulb temperature (the average dry-bulb temperature over 50 hours is not guaranteed). However, in actual use, the outdoor dry-bulb temperature rarely reaches the design temperature calculated in the load calculation, and the outdoor dry-bulb temperature varies daily depending on the time of day. Furthermore, the air conditioning load can vary significantly between different times of the day. In comfort-oriented centralized air-conditioned buildings, the problem of insufficient total cooling capacity is almost nonexistent. In most cases, the time during which all installed chiller units operate at full load simultaneously is never observed throughout the year; in some projects, the time during which all units operate simultaneously is very short or never occurs at all. This indicates that the total installed capacity of chiller units in many refrigeration rooms is excessive, resulting in wasted investment. Simultaneously, the increased installed capacity of individual units also leads to reduced energy efficiency when operating under low-load conditions.

[0004] During daytime operation, the number of chiller units operating in central air conditioning systems with building control (BA) systems increases with the terminal air conditioning load. A well-designed BA system will also design the chiller unit start-up strategy based on the chiller unit load characteristic curves; however, this involves complex logic programming and numerous detection devices. Furthermore, the control logic is unique for different buildings, making this control method complex, increasing the cost of BA systems, and preventing their replication. A significant proportion of large public buildings lack BA systems, further necessitating manual operation of the air conditioning systems and resulting in unnecessary waste during operation. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a control method for an air conditioning system, comprising: acquiring target temperature and current weather forecast data, and predicting air conditioning load using a building operation status database; acquiring the current stored energy of an energy storage unit, and predicting the preprocessing time of the energy storage unit using an energy storage unit preprocessing database; operating the air conditioning system according to the predicted air conditioning load, and storing the additional energy generated during the operation of the air conditioning system into the energy storage unit; and, based on the predicted preprocessing time of the energy storage unit, having the energy storage unit preprocess various areas within the building through a water distributor.

[0006] Furthermore, air conditioning load is predicted based on the building operation database:

[0007] When the predicted air conditioning load is less than the current energy storage capacity of the energy storage unit, the energy storage unit is activated first to supply energy to the end of the air conditioning system.

[0008] When the predicted air conditioning load exceeds the current energy storage capacity of the energy storage unit, the energy storage unit will be given priority for power supply during peak electricity price periods.

[0009] When the energy storage unit has a surplus after meeting the peak load, the energy storage unit will be given priority for power supply during the electricity price parity period; when the capacity of the energy storage unit is insufficient, the energy storage unit and the air conditioning system will be used together for power supply.

[0010] Furthermore, the current energy storage capacity of the energy storage unit is monitored. When the current energy storage capacity reaches 1.1-1.4 times the predicted air conditioning load for the day, the energy storage operation of the energy storage unit is stopped.

[0011] Furthermore, establishing a building operation status database includes the following steps: acquiring indoor and outdoor air conditions for each time period of the day, instantaneous air conditioning load of the entire system, total daily air conditioning load, operating efficiency of chiller units under different load conditions, and energy storage unit efficiency data; establishing functional relationships between various parameters; and forming a building operation status database.

[0012] Furthermore, establishing a pre-processing database for energy storage units includes the following steps: acquiring indoor and outdoor air conditions, the time it takes for the indoor temperature in the pre-processing area of ​​the air conditioning system to reach the set temperature, the air conditioning load required in the pre-processing area, and energy storage unit efficiency data; establishing the functional relationship between each parameter; forming an energy storage unit pre-processing database; and obtaining the pre-processing time of the energy storage unit in each pre-processing area and the advance start-up time of the air conditioning system.

[0013] On the other hand, the present invention also provides an energy-saving air conditioning system, including a chiller, a hot water boiler, a water distributor, and a water collector, as well as an energy storage unit and a control unit. The chiller is connected to the water distributor and the water collector, the hot water boiler is connected to the water distributor and the water collector, and an end loop pipe for connecting to the user terminal is connected between the water distributor and the water collector. The energy storage unit is connected to the water distributor and the water collector, and the control unit is used to establish a building operation status database and an energy storage unit preprocessing database.

[0014] Furthermore, the energy storage unit includes an energy storage tank, a third energy storage pipe, and a fourth energy storage pipe. The energy storage tank is connected to the water distributor and the water collector through the first energy storage pipe and the second energy storage pipe, respectively. One end of the third energy storage pipe and the fourth energy storage pipe are connected to the first energy storage pipe, and the other end is connected to the second energy storage pipe.

[0015] Furthermore, the first energy storage pipe is connected to the water inlet of the energy storage tank, and the second energy storage pipe is connected to the water outlet of the energy storage tank.

[0016] Furthermore, the first, second, third, and fourth energy storage pipes are each equipped with an energy storage valve with adjustable flow rate.

[0017] Furthermore, the energy storage tank includes an inlet main pipe and an outlet main pipe, and multiple water supply pipes are connected in parallel between the inlet main pipe and the outlet main pipe, with at least one water tank unit connected in series on each water supply pipe.

[0018] By employing the above technical solutions, this invention has the following advantages compared to existing technologies:

[0019] 1) The energy-saving air conditioning system control method provided by the present invention, by using an energy storage unit, can provide cooling and heating to various areas during peak electricity consumption periods or peak electricity price periods, which can significantly improve the power supply efficiency of urban or regional power grids, transfer peak electricity demand, balance grid load, and save air conditioning operating costs; it can also be more effectively integrated with building automation (BA) systems, making the entire system control simpler and more efficient, and reducing the total investment in BA systems.

[0020] 2) The energy-saving air conditioning system control method provided by the present invention can reduce the installed capacity and operating energy consumption of the air conditioning system by setting up an energy storage unit, thereby reducing the initial investment and overall operating costs of the equipment.

[0021] 3) The energy-saving air conditioning system control method provided by this invention predicts the air conditioning load based on a building operation status database. When the predicted air conditioning load is less than the current energy storage capacity of the energy storage unit, the energy storage unit is preferentially activated to supply energy to the air conditioning system terminals. When the predicted air conditioning load is greater than the current energy storage capacity of the energy storage unit, the energy storage unit is preferentially used to supply energy during peak electricity price periods. Wherein, when the current energy storage capacity of the energy storage unit meets the peak load and has a surplus, the energy storage unit is preferentially used to supply energy during off-peak electricity price periods. When the capacity of the energy storage unit is insufficient, the energy storage unit and the air conditioning system are used for combined energy supply. Furthermore, by establishing an energy storage unit pre-processing database, the pre-processing time of the energy storage unit can be predicted, which can accurately determine the advance activation time of the energy storage unit in the area requiring pre-processing, and can also accurately predict the advance activation time of the air conditioning system, thereby reducing the advance activation time of the energy storage unit and the air conditioning system and reducing unnecessary energy consumption. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of an energy-saving air conditioning system provided in Embodiment 2 of the present invention;

[0024] Figure 2 This is a schematic diagram of the energy storage water tank provided in Embodiment 2 of the present invention;

[0025] Figure 3 This is a schematic diagram of the structure of the water tank unit in the energy storage water tank provided in Embodiment 2 of the present invention.

[0026] 1-Energy storage unit; 10-Energy storage tank; 11-Inlet main pipe; 12-Outlet main pipe; 13-Water supply pipe; 131-First regulating valve 131; 132-Second regulating valve; 133-Fourth regulating valve; 14-Water tank unit; 141-Tank body; 142-Water tank inlet pipe; 143-Water tank outlet pipe; 144-Temperature sensor; 145-Flow sensor; 146-Drain pipe; 1461-Fifth regulating valve; 147-Water baffle; 148-Anti-backflow assembly; 149-Anti-backflow hole; 15-First bypass pipe; 151-Third regulating valve; 1 6-Second bypass pipe; 17-First energy storage pipe; 171-First energy storage valve; 18-Second energy storage pipe; 181-Second energy storage valve; 19-Third energy storage pipe; 191-Third energy storage valve; 110-Fourth energy storage pipe; 1101-Fourth energy storage valve; 2-Chiller unit; 21-Sixth regulating valve; 22-Seventh regulating valve; 3-Hot water boiler; 31-Eighth regulating valve; 32-Ninth regulating valve; 4-Water distributor; 5-Water collector; 6-User water supply pipe; 61-Water supply valve; 7-User return water pipe; 71-Return water valve; 8-Connecting pipe. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In the accompanying drawings, the dimensions and relative dimensions of certain parts may be enlarged for clarity.

[0028] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connection" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0029] In the description of this invention, terms such as "upper," "lower," "left," "right," "front," and "rear," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0030] Furthermore, in the description of this invention, the terms "first" and "second" are used merely for descriptive distinction and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Additionally, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature. Example 1

[0031] This invention provides a control method for an energy-saving air conditioning system, comprising: acquiring target temperature and current weather forecast data, and predicting air conditioning load using a building operation status database; acquiring the current stored energy of an energy storage unit, and predicting the pre-processing time of the energy storage unit using an energy storage unit pre-processing database; operating the air conditioning system according to the predicted air conditioning load, and storing the additional energy generated during the operation of the air conditioning system into the energy storage unit; and, based on the predicted pre-processing time of the energy storage unit, the energy storage unit pre-processes various areas within the building through a water distributor.

[0032] Specifically, depending on the outdoor temperature, the air conditioning system can be used for cooling and / or heating to meet usage needs. When the air conditioning system operates in cooling mode, energy storage unit 1 is used to store cold energy; in this case, energy storage unit 1 is a cold storage unit. When the air conditioning system operates in heating mode, energy storage unit 1 is used to store heat energy; in this case, energy storage unit 1 is a heat storage unit. When the air conditioning system is running, any excess cold or heat generated is transferred to the energy storage unit for storage. The cold energy stored in the energy storage unit can be used for pre-cooling various areas within the building, or the energy storage unit 1 can store... The stored energy can be used to preheat various areas within the building, thereby reducing the operating time of the air conditioning system and effectively reducing costs. Of course, the cold / heat stored in the energy storage unit can supply cooling / heating to the terminal of the air conditioning system during peak electricity consumption or peak electricity price periods. In this embodiment, the air conditioning system refrigeration is used as an example for detailed explanation. The air conditioning system refrigerates through the chiller unit 2. The energy storage unit 1 can perform cold storage operation on surplus cold energy during the daytime operation of the air conditioning system to store cold energy, and it can also perform cold storage operation on nighttime time-of-use electricity prices to store cold energy.

[0033] Optimizing the implementation method and establishing a building operation status database includes the following steps: acquiring indoor and outdoor air conditions for each time period of the day, the instantaneous air conditioning load of the entire system, the total daily air conditioning load, the operating efficiency of the chiller unit under different load conditions, and the efficiency data of the energy storage unit. Indoor and outdoor air conditions refer to dry-bulb temperature, wet-bulb temperature, atmospheric pressure, and humidity. After long-term data processing, a building operation status database is established. Specifically, it acquires indoor and outdoor air conditions at 1-minute intervals each day, the instantaneous air conditioning load of the entire system, and the total daily air conditioning load. By accumulating data over a long period, a building operation status database is established. Then, based on outdoor weather forecasts, the total air conditioning load for the next few hours, the current day, or the next few days can be predicted. During the daytime operating hours of the air conditioning system, a reasonable chiller and energy storage unit activation mechanism is calculated based on the predicted air conditioning load to ensure the operational needs of the air conditioning system.

[0034] Preferably, the chiller unit 2 can be set to operate at 85% of its rated load to ensure that the chiller unit 2 is always in the optimal operating state. When the predicted air conditioning load is less than the 85% rated load of a single chiller unit 2, one chiller unit 2 can be turned on. The cooling capacity generated by the chiller unit 2 is preferably supplied to the user end, and the energy storage unit 1 is turned on, storing the excess cooling capacity generated by the chiller unit 2 in the energy storage unit 1. When the predicted air conditioning load is equal to the 85% rated load of a single chiller unit 2, one chiller unit 2 can be turned on. The cooling capacity generated by the chiller unit 2 is only supplied to the user end, and the energy storage unit 1 is turned off. When the predicted air conditioning load is greater than the 85% rated load of a single chiller unit 2, one more chiller unit 2 can be turned on sequentially until the chiller unit 2 meets the terminal load demand. The cooling capacity generated by the chiller unit 2 is preferably supplied to the user end, and the excess cooling capacity generated by the chiller unit 2 is stored in the energy storage unit 1.

[0035] The optimized implementation method for establishing a pre-processing database for energy storage units includes the following steps: acquiring indoor and outdoor air conditions, the time it takes for the indoor temperature in the pre-processing area of ​​the air conditioning system to reach the set temperature, the air conditioning load required in the pre-processing area, and energy storage unit efficiency data. After the data has been running for a long time, an energy storage unit pre-processing database is established, which can obtain the pre-processing time of energy storage unit 1 in each pre-processing area and the advance start-up time of the air conditioning system.

[0036] Specifically, in actual use, the chiller unit 2 of the air conditioning system needs to be turned on for a period of time before the temperature in the space reaches the set temperature. In order to reduce the early start of the air conditioning system and save costs, the energy storage unit 1 can be turned on to pre-cool each area in advance, so that the temperature of each area is close to or equal to the set temperature, thereby reducing the pre-cooling time of the air conditioning system and reducing costs.

[0037] Preferably, since different areas within a building require different pre-cooling times, the pre-cooling time can be accurately determined by establishing a pre-processing database for energy storage units. This allows for zoned pre-cooling of each area, ensuring efficient pre-cooling operations and reducing cooling loss. Simultaneously, by establishing a pre-processing database for energy storage units, the pre-start time of the chiller units 2 in the air conditioning system can also be accurately predicted, improving the operational efficiency of the space system and enhancing the user experience.

[0038] The operating strategy of the air conditioning system in this application is as follows:

[0039] By utilizing various databases and intelligent weather forecasts, future air conditioning loads can be accurately predicted. Furthermore, based on the air conditioning load size, chiller capacity, and energy storage unit capacity, the optimal operating strategy can be calculated to achieve the most energy-efficient and cost-effective operating mode.

[0040] A database can be established to record load conditions and future load demands in real time.

[0041] When the predicted air conditioning load is less than the current energy storage capacity of the energy storage unit, the energy storage unit is activated first for cooling at the end of the air conditioning system.

[0042] When the predicted air conditioning load exceeds the current energy storage capacity of the energy storage unit, the energy storage unit will be used for cooling during peak electricity price periods (which can be set according to local electricity prices) and peak electricity consumption periods. If the energy storage system capacity meets the peak load and has a surplus, the energy storage system will also be used for cooling during off-peak periods. When the energy storage system capacity is insufficient, the energy storage system and chiller units will be used together for cooling. This can effectively utilize the energy storage capacity of the energy storage unit, avoid the limitations of peak electricity consumption periods and peak electricity price periods, and reduce costs and increase efficiency.

[0043] When the terminal load of the air conditioning system is high in summer, and multiple chiller units need to operate simultaneously to provide cooling, the above control strategy can be adopted according to the predicted air conditioning load. When the load increases, newly started chiller units will increase cooling supply. However, the load efficiency of newly started chiller units is relatively low. Therefore, the chiller units can be operated at a fixed load (such as 85%-90% of the rated load, preferably 90% of the rated load) to ensure the operating efficiency of the chiller units. The chiller units are given priority to supply users. At the same time, the excess cooling capacity generated by the chiller units is stored by the energy storage unit.

[0044] Preferably, the inlet end of the energy storage unit 1 is equipped with a flow sensor, which can monitor the cooling capacity of the energy storage unit; the output cooling capacity can be controlled by adjusting the flow rate at the outlet end of the energy storage unit.

[0045] In an optimized implementation, the total energy storage of energy storage unit 1 is monitored. In this embodiment, the air conditioning system is used for cooling, and energy storage unit 1 is used for cold storage. The amount of cold stored in energy storage unit 1 can be calculated by setting an energy meter at the water inlet of energy storage unit 1. When the total amount of cold storage reaches 1.1-1.4 times the predicted air conditioning load for the day, the cold storage operation of energy storage unit 1 is stopped. Preferably, when the total amount of cold storage reaches 1.2 times the predicted air conditioning load for the day, the cold storage operation of energy storage unit 1 is stopped. Example 2

[0046] As per the instruction manual Figure 1 As shown, the present invention also provides an energy-saving air conditioning system, including a chiller unit 2, a hot water boiler 3, a water distributor 4, and a water collector 5, as well as an energy storage unit 1 and a control unit. The chiller unit 2 is connected to the water distributor 4 and the water collector 5. The chiller unit 2 is used for cooling. There is at least one chiller unit 2, which can be set according to needs to meet user requirements. The hot water boiler 3 is connected to the water distributor 4 and the water collector 5. A terminal loop pipe for connecting the water distributor 4 and the water collector 5 is connected between them. The energy storage unit 1 is connected to the water distributor 4 and the water collector 5. The control unit is used to establish a building operation status database and an energy storage unit preprocessing database.

[0047] Preferably, when the air conditioning system starts the cooling program, the water in the water collector 5 is sent to the chiller unit 2 for cooling through the pipeline, and then sent to the distributor 4 for supply to the user end; when the air conditioning system starts the heating program, the water in the water collector 5 is sent to the hot water boiler 3 for heating through the pipeline, and then sent to the distributor 4 for supply to the user end.

[0048] A sixth regulating valve 21 is installed on the pipeline between the chiller unit 2 and the water distributor 4, and a seventh regulating valve 22 is installed on the pipeline between the chiller unit 2 and the water collector 5; the sixth regulating valve 21 is preferably an electric valve, and the seventh regulating valve 22 is preferably an electric valve.

[0049] An eighth regulating valve 31 is installed on the pipeline between the hot water boiler 3 and the water distributor 4, and a ninth regulating valve 32 is installed on the pipeline between the hot water boiler 3 and the water collector 5; the eighth regulating valve 31 is preferably an electric valve, and the ninth regulating valve 32 is preferably an electric valve.

[0050] In this embodiment, the cooling system of an air conditioning system is used as an example. The terminal loop pipeline includes multiple user water supply pipes 6 connected to the water distributor 4 and user return water pipes 7 connected to the water collector 5. The user return water pipes 7 are configured in a one-to-one correspondence with the water supply pipes 6. Each user water supply pipe 6 is used to supply cooling to different areas. The number of user water supply pipes 6 and user return water pipes 7 is set according to actual needs. Each user water supply pipe 6 is equipped with a water supply valve 61, which can adjust the opening and thus adjust the flow rate. Each user return water pipe 7 is equipped with a return water valve 71, which can adjust the opening and thus adjust the flow rate. The water supply valve 61 is preferably an electric valve, and the return water valve 71 is preferably an electric valve.

[0051] Preferably, a connecting pipe 8 is also connected between the water collector 5 and the water distributor 4 to balance the water pressure between the water collector 5 and the water distributor 4.

[0052] In an optimized implementation, the energy storage unit 1 includes an energy storage tank 10, a third energy storage pipe 19, and a fourth energy storage pipe 110. The energy storage tank 10 is connected to the water distributor 4 and the water collector 5 through the first energy storage pipe 17 and the second energy storage pipe 18, respectively. One end of the third energy storage pipe 19 and the fourth energy storage pipe 110 is connected to the first energy storage pipe 17, and the other end is connected to the second energy storage pipe 18.

[0053] In an optimized implementation, the first energy storage pipe 17 is connected to the inlet end of the energy storage tank 10, and the second energy storage pipe 18 is connected to the outlet end of the energy storage tank 10.

[0054] In an optimized implementation, the first energy storage pipe 17, the second energy storage pipe 18, the third energy storage pipe 19, and the fourth energy storage pipe 110 are each equipped with an adjustable flow energy storage valve. Specifically, the first energy storage pipe 17 is equipped with a first energy storage valve 171, the second energy storage pipe 18 is equipped with a second energy storage valve 181, the third energy storage pipe 19 is equipped with a third energy storage valve 191, and the fourth energy storage pipe 110 is equipped with a fourth energy storage valve 1101.

[0055] Preferably, an energy meter 172 is also provided on the first energy storage pipe 17.

[0056] The air conditioning system in this application is mainly used for central air conditioning in commercial buildings, and its operation strategy is as follows:

[0057] 1) Energy storage operation during daytime working hours:

[0058] The sixth regulating valve 21 and the seventh regulating valve 22 on the chiller unit pipeline are opened;

[0059] The eighth regulating valve 31 and the ninth regulating valve 32 on the hot water boiler pipeline are closed;

[0060] The water supply valve 61 on the manifold connection pipe is opened according to actual needs;

[0061] The first energy storage valve 171 on energy storage unit 1 is open, the second energy storage valve 181 is open, the third energy storage valve 191 is closed, and the fourth energy storage valve 1101 is closed. Energy storage is performed while ensuring the daytime cooling supply of the air conditioning system. When the total energy storage capacity of energy storage unit 1 reaches 1.2 times the predicted air conditioning load for the day, the energy storage operation of energy storage unit 1 is stopped, and the first energy storage valve 171, the second energy storage valve 181, the third energy storage valve 191, and the fourth energy storage valve 1101 are closed.

[0062] 2) Nighttime time-of-use electricity pricing energy storage operation:

[0063] The sixth regulating valve 21 and the seventh regulating valve 22 on the chiller unit pipeline are opened;

[0064] The eighth regulating valve 31 and the ninth regulating valve 32 on the hot water boiler pipeline are closed;

[0065] The water supply valve 61 on the manifold connection pipe is closed. Of course, if there is a need for nighttime use, the corresponding water supply valve 61 can be opened as needed.

[0066] The first energy storage valve 171 on energy storage unit 1 is open, the second energy storage valve 181 is open, the third energy storage valve 191 is closed, and the fourth energy storage valve 1101 is closed.

[0067] When the terminal load demand of the central air conditioning system is zero, and during the nighttime time-of-use electricity pricing period, the energy storage unit 1 is turned on. When the water temperature in the energy storage tank 10 of the energy storage unit 1 reaches the predetermined temperature (assuming 7°C), the operation of the energy storage unit 1 is stopped, and the first energy storage valve 171, the second energy storage valve 181, the third energy storage valve 191 and the fourth energy storage valve 1101 are closed.

[0068] 3) During daytime working hours, the energy storage unit provides auxiliary cooling:

[0069] The sixth regulating valve 21 and the seventh regulating valve 22 on the chiller unit pipeline are opened;

[0070] The eighth regulating valve 31 and the ninth regulating valve 32 on the hot water boiler pipeline are closed;

[0071] The water supply valve 61 on the manifold connection pipe is opened according to actual needs;

[0072] The first energy storage valve 171 on the energy storage unit 1 is closed, the second energy storage valve 181 is closed, the third energy storage valve 191 is open, and the fourth energy storage valve 1101 is open, which can be used for auxiliary cooling.

[0073] 4) Nighttime pre-cooling of energy storage units:

[0074] The sixth regulating valve 21 and the seventh regulating valve 22 on the chiller unit pipeline are closed;

[0075] The eighth regulating valve 31 and the ninth regulating valve 32 on the hot water boiler pipeline are closed;

[0076] The water supply valve 61 on the manifold connection pipe is opened according to actual needs;

[0077] The first energy storage valve 171 on the energy storage unit 1 is closed, the second energy storage valve 181 is closed, the third energy storage valve 191 is open, and the fourth energy storage valve 1101 is open, which can be used for pre-cooling of each area.

[0078] Preferably, in pre-cooling operation, because the pre-cooling times of air conditioning in different areas of the building are inconsistent, conventional air conditioning systems set the pre-cooling start time earlier based on the worst-case scenario, which leads to increased energy consumption of chiller unit 2. In this application, the building's air-conditioned areas are divided into zones, such as A, B, and C. The user water supply pipes 6 on the manifold 4 are connected to each zone to obtain the pre-cooling time of zones A, B, and C respectively. Zones with longer pre-cooling times or different operating times are separated. Zones requiring longer pre-cooling times can be cooled separately by energy storage unit 1, while the air conditioning system's chiller unit 2 only considers zones with shorter pre-cooling times. This significantly reduces the overall pre-cooling time of the air conditioning system, thereby achieving energy savings.

[0079] Optimized implementation methods, as shown in the appendix to the instruction manual. Figure 2 As shown, the energy storage tank 10 includes an inlet main pipe 11, an outlet main pipe 12, and multiple water supply pipes 13. The water supply pipes 13 are connected in parallel to form a parallel pipeline. The inlet end of the parallel pipeline is connected to the inlet main pipe 11, and the outlet end of the parallel pipeline is connected to the outlet main pipe 12. At least one water tank unit 14 is connected in series on each water supply pipe 13. The inlet end and outlet end of the water supply pipe 13 are respectively provided with a first regulating valve 131 and a second regulating valve 132. The inlet main pipe 11 is connected to the first energy storage pipe 17, and the outlet main pipe 12 is connected to the second energy storage pipe 18.

[0080] Specifically, the energy storage tank 10 includes an inlet main pipe 11 and an outlet main pipe 12. At least one water tank unit 14 is connected in series on each water supply pipe 13. A first regulating valve 131 and a second regulating valve 132 are provided on the water supply pipe 13. The opening and closing of the water supply pipe 13 can be adjusted by the valves. An appropriate number of water tank units 14 on the water supply pipe 13 can be opened as needed to meet different load requirements.

[0081] The optimized implementation also includes a first bypass pipe 15, with both ends of the first bypass pipe 15 connected to two of the water supply pipes 13 respectively. A third regulating valve 151 is provided on the first bypass pipe 15. Specifically, the first bypass pipe 15 connects the two water supply pipes 13, which can connect the water tank units 14 on the two water supply pipes 13 in series. This allows the water tank units 14 on the water supply pipes 13 to be connected in parallel or in series. The number of water tank units 14 that can be opened can be adjusted according to load changes to meet usage requirements.

[0082] Specifically, at least two first bypass pipes 15 are connected between the two water supply pipes 13, one of which is located at the inlet end of the water supply pipe 13 and upstream of the first regulating valve 131, and the other is located at the outlet end of the water supply pipe 13 and upstream of the second regulating valve 132.

[0083] In some embodiments, a first bypass pipe 15 is connected between adjacent water supply pipes 13 to connect each water tank unit 14.

[0084] The optimized implementation also includes a second bypass pipe 16, with both ends of the second bypass pipe 16 connected to the first bypass pipe 15. Specifically, the second bypass pipe 16 is connected to the first bypass pipe 15 located between two identical water supply pipes 13, connecting the water tank units 14 on the water supply pipes 13 in series. Each first bypass pipe 15 is equipped with two third regulating valves 151. The second bypass pipe 16 divides the first bypass pipe 15 into two sections, each equipped with a third regulating valve 151. The third regulating valves 151 are located between the bypass points of the second bypass pipe 16 and the first bypass pipe 15, and between the first bypass pipe 15 and the water supply pipe 13. By setting the first bypass pipe 15 and the second bypass pipe 16 and adjusting the corresponding valves, the water tank units 14 on the water supply pipes 13 can be connected in parallel or in series to meet different load requirements.

[0085] In an optimized implementation, multiple water tank units 14 are connected in series on each water supply pipe 13, and a fourth regulating valve 133 is provided between adjacent water tank units 14. Specifically, multiple first bypass pipes 15 are provided on the two water supply pipes 13, that is, both the inlet and outlet ends of the water tank unit 14 are provided with first bypass pipes 15, allowing for individual adjustment of each water tank unit 14. This enables precise maintenance or replacement of one or more water tank units 14 without affecting the normal operation of the energy storage tank 10. Different numbers of water tank units 14 can be connected in series or parallel to meet load requirements.

[0086] Specifically, the connection point between the first bypass pipe 15 and the water supply pipe 13 is located at the outlet end of the water tank unit 14 and upstream of the first regulating valve 131.

[0087] The number of water supply pipes 13 of the energy storage tank 10 can be set according to actual needs, and the number of water tank units 14 on each water supply pipe 13 can be set according to actual needs. In this application, there is no limitation on the number of water supply pipes 13 and water tank units 14.

[0088] Optimized implementation methods, as shown in the appendix to the instruction manual. Figure 3 As shown, the water tank unit 14 includes a tank body 141. A water tank inlet pipe 142 and a water tank outlet pipe 143 are respectively provided at the top and bottom of the tank body 141. A temperature sensor 144 is provided on both the water tank inlet pipe 142 and the water tank outlet pipe 143, and a flow sensor 145 is provided on the water tank outlet pipe 143. Specifically, each water tank unit 14 has the same structure. If one water tank unit 14 is provided on the water supply pipe 13, then the water tank inlet pipe 142 and the water tank outlet pipe 143 are respectively connected to the water supply pipe 13. If two or more water tank units 14 are provided on the water supply pipe 13, then the water tank outlet pipe 143 and the water tank inlet pipe 142 of adjacent water tank units 14 are connected, and the first and last two water tank units 14 are connected to the water supply pipe 13, so that each water tank unit 14 is connected in series on the water supply pipe 13.

[0089] In an optimized implementation, a drain pipe 146 is provided at the bottom of the housing 141 to drain the water inside the housing 141 for easy maintenance; preferably, a fifth regulating valve 1461 is provided on the drain pipe 146.

[0090] In an optimized implementation, the housing 141 is provided with multiple water-blocking plates 147 that are alternately connected to both sides of the housing 141 in sequence, and the multiple water-blocking plates 147 are arranged vertically in sequence. Specifically, the housing 141 is divided into multiple water storage areas from top to bottom by multiple water-blocking plates 147. The water tank inlet pipe 142 is located at the top of the housing 141, and the water tank outlet pipe 143 is located at the bottom of the housing 141. The water-blocking plates 147 are alternately connected to both sides of the housing 141 from top to bottom. The end of the water-blocking plate 147 away from the connecting end is a free end, and there is a gap between the free end and the housing 141. This gap is a water flow channel, so that water enters the housing 141 through the water tank inlet pipe 142 and flows through the water-blocking plates 147 in sequence until the housing 141 is filled.

[0091] Preferably, a flow sensor is also provided on the water tank inlet pipe 142 to record the water volume in the water tank unit 14. The flow sensor can be adjusted to open the appropriate water tank unit 14 according to the load demand to meet the water supply requirements of the water tank.

[0092] In an optimized implementation, an anti-backflow component 148 is provided inside the tank 141 along the water flow direction. The anti-backflow component 148 is located between adjacent baffles 147 or between baffles 147 and the tank 141. Specifically, the baffles 147 divide the tank 141 into multiple water storage areas from top to bottom, and each water storage area is provided with an anti-backflow component 148. The anti-backflow component 148 can prevent water in the tank 141 from flowing back, so as to ensure that the water can flow sequentially through the water tank unit 14 and the main water outlet pipe 12.

[0093] In an optimized implementation, the anti-backflow component 148 includes two anti-backflow plates, the distance between the two anti-backflow plates decreases sequentially along the water flow direction and an anti-backflow hole 149 is formed at the end, and the anti-backflow plates are disposed on the water-blocking plate 147 or the box body 141.

[0094] Preferably, in order to ensure that the water tank unit 14 has a good heat preservation effect, the tank body 141 is covered with an insulation layer.

[0095] As one specific implementation method, as shown in the appendix to the instruction manual. Figure 2 The diagram shows the structure of the energy storage tank 10. Four water supply pipes 13, denoted as L1, L2, L3, and L4, are connected in parallel between the main inlet pipe 11 and the main outlet pipe 12. Each water supply pipe 13 has four water tank units 14 connected in series. Each water supply pipe 13 has a first regulating valve 131 at its inlet end, denoted as V1a, V2a, V3a, and V4a respectively. Each water supply pipe 13 has a second regulating valve 132 at its outlet end, denoted as... V1e, V2e, V3e and V4e; a fourth regulating valve 133 is provided between adjacent water tank units 14, wherein the fourth regulating valve 133 in L1 is referred to as V1b, V1c and V1d in sequence, the fourth regulating valve 133 in L2 is referred to as V2b, V2c and V2d in sequence, the fourth regulating valve 133 in L3 is referred to as V3b, V3c and V3d in sequence, and the fourth regulating valve 133 in L4 is referred to as V4b, V4c and V4d in sequence.

[0096] To facilitate adjustment of each water tank unit, multiple first bypass pipes 15 are connected between L1 and L2, and second bypass pipes 16 are connected between corresponding first bypass pipes 15. Multiple first bypass pipes 15 are also connected between L3 and L4, and second bypass pipes 16 are connected between corresponding first bypass pipes 15. A third regulating valve 151 is installed on each of the first bypass pipes 15. The third regulating valve 151 on the first bypass pipe 15 between L1 and L2 is denoted as V1f, ... V1g, V1h, V1i, V1j, and V2f, V2g, V2h, V2i, V2j; the third regulating valve 151 on the first bypass pipe 15 between L3 and L4 is sequentially named V3f, V3g, V3h, V3i, V3j, and V4f, V4g, V4h, V4i, V4j. Through the above-mentioned bypass pipes and regulating valves, each water tank unit can be adjusted independently, making maintenance convenient, and the number of water tank units that can be opened can be adjusted according to load requirements.

[0097] In some embodiments, the L1 and L2 water supply pipes can be connected in parallel and in series to form a first unit group, and the L3 and L4 water supply pipes can be connected in parallel and in series to form a second unit group. The first unit group and the second unit group can be connected to pipes separately for use, and can be used for cold storage and heat storage respectively. They can be used when the air conditioning system switches between cooling and heating modes, which is convenient for simultaneous cold storage and simultaneous heat storage.

[0098] Preferably, the second regulating valve 132 is an electric valve, which can adjust the opening degree and thus regulate the flow rate on the water supply pipe 13; the first regulating valve 131 is preferably an electric valve, which can be opened and closed; the third regulating valve 151 is preferably an electric valve, which can be opened and closed; and the fourth regulating valve 133 is preferably an electric valve, which can be opened and closed.

[0099] In this embodiment, the water tank unit 14 can be used to store condensate. The condensate enters the water tank unit 14 through the main water inlet pipe 11 and is stored in the water tank unit 14 to provide cooling. Of course, the water tank unit can also be used to store hot water to provide heating. In this embodiment, cooling is used as an example for explanation.

[0100] When the energy storage tank 10 is used to store condensate for cooling, the cooling capacity calculation formula for the cooling system is:

[0101] Q = C·M·ΔT (Formula 1)

[0102] In Equation 1: Q is the cooling capacity of the cooling system (kJ / h); C is the specific heat capacity of water, 4.187 (kJ / (kg·℃)); M is the water flow rate (kg / h); ΔT is the temperature difference between the supply and return water (℃).

[0103] When the terminal demand load changes, i.e., the cooling capacity (Q) of the system changes, the cooling capacity of the cooling system is directly proportional to the flow rate while ensuring that the supply and return water temperature difference remains constant. The water temperature in the water tank unit 14 can be set to 7℃ or 12℃. In actual use, a water pump is connected to the main outlet pipe 12, preferably a variable frequency pump. The flow rate on the main outlet pipe 12 can be adjusted by the variable frequency pump and the opening of various electric valves.

[0104] When the terminal load demand is small, if the water tank unit 14 on only one water supply pipe 13 can meet the supply demand, the water tank unit 14 on any one of the water supply pipes 13 (L1, L2, L3, L4) can be opened. Taking the opening of the water tank unit 14 on L1 as an example, the flow velocity in the water supply pipe of L1 is within a reasonable range (set ≤1m / s). By adjusting the opening of the V1e valve and the water pump frequency to control the system water flow, the system cooling capacity demand can be met.

[0105] When the terminal load demand is high (i.e., the flow velocity in the L1 water supply pipe > 1 m / s), the flow sensor at the outlet pipe 143 of the L1 water tank unit 14 detects the water flow velocity in the pipe. When the water flow velocity in the L1 water supply pipe > 1 m / s, the electric valves (V2a, V2b, V2c, V2d, V2e) on the L2 water supply pipe are opened, allowing the L1 and L2 water tank units to operate in parallel. Electric valves V1e and V2e share the load required by the terminal load. When the water flow velocity in the L1 and L2 water supply pipes 13 > 1 m / s, and the load demand cannot be met, the electric valves on the L3 water supply pipe 13 are opened. Based on demand, the L3 water tank unit 14 is opened sequentially until the demand is met. Electric valves V1e, V2e, and V3e share the load required by the terminal load. This process continues until the terminal load demand is met. The cooling capacity supplied by the energy storage tank 10 is greater than the maximum load demand.

[0106] Those skilled in the art will understand that the present invention can be implemented in many other specific forms without departing from the spirit and scope of the invention. Although embodiments of the invention have been described, it should be understood that the invention is not limited to these embodiments, and those skilled in the art can make changes and modifications within the spirit and scope of the invention as defined in the appended claims.

Claims

1. A control method for an energy-saving air conditioning system, characterized in that, include: The system acquires target temperature and weather forecast data, and predicts air conditioning load using a building operation status database; it acquires the current energy storage capacity of the energy storage unit, and predicts the pre-processing time of the energy storage unit using an energy storage unit pre-processing database; it operates the air conditioning system based on the predicted air conditioning load, and stores the additional energy generated during the operation of the air conditioning system into the energy storage unit; based on the predicted pre-processing time of the energy storage unit, the energy storage unit pre-processes each area within the building through a water distributor. The establishment of a building operation status database includes the following steps: acquiring indoor and outdoor air conditions for each time period of the day, instantaneous air conditioning load of the entire system, total daily air conditioning load, operating efficiency of chiller units under different load conditions, and energy storage unit efficiency data; establishing functional relationships between various parameters; and forming a building operation status database. Establishing a pre-processing database for energy storage units includes the following steps: acquiring indoor and outdoor air conditions, the time it takes for the indoor temperature in the pre-processing area of ​​the air conditioning system to reach the set temperature, the air conditioning load required in the pre-processing area, and energy storage unit efficiency data; establishing the functional relationship between each parameter; forming an energy storage unit pre-processing database; and obtaining the pre-processing time of the energy storage unit in each pre-processing area and the advance start-up time of the air conditioning system.

2. The control method for an energy-saving air conditioning system according to claim 1, characterized in that, Predict air conditioning load based on building operation database: When the predicted air conditioning load is less than the current energy storage capacity of the energy storage unit, the energy storage unit is activated first to supply energy to the end of the air conditioning system. When the predicted air conditioning load exceeds the current energy storage capacity of the energy storage unit, the energy storage unit will be given priority for power supply during peak electricity price periods. When the energy storage unit has a surplus after meeting the peak load, the energy storage unit will be given priority for power supply during the electricity price parity period; when the capacity of the energy storage unit is insufficient, the energy storage unit and the air conditioning system will be used together for power supply.

3. The control method for an energy-saving air conditioning system according to claim 1, characterized in that, Monitor the current energy storage capacity of the energy storage unit. When the current energy storage capacity reaches 1.1-1.4 times the predicted air conditioning load for the day, stop the energy storage operation of the energy storage unit.

4. An air conditioning system based on an energy-saving control method as described in any one of claims 1-3, comprising a chiller, a hot water boiler, a water distributor, and a water collector, characterized in that, It also includes an energy storage unit and a control unit. The chiller is connected to the water distributor and the water collector. The hot water boiler is connected to the water distributor and the water collector. An end loop pipe for connecting to the user terminal is connected between the water distributor and the water collector. The energy storage unit is connected to the water distributor and the water collector. The control unit is used to establish a building operation status database and an energy storage unit preprocessing database.

5. The air conditioning system based on the energy-saving control method according to claim 4, characterized in that, The energy storage unit includes an energy storage tank, a third energy storage pipe, and a fourth energy storage pipe. The energy storage tank is connected to the water distributor and the water collector through the first energy storage pipe and the second energy storage pipe, respectively. One end of the third energy storage pipe and the fourth energy storage pipe are connected to the first energy storage pipe, and the other end is connected to the second energy storage pipe.

6. The air conditioning system based on the energy-saving control method according to claim 5, characterized in that, The first energy storage pipe is connected to the inlet end of the energy storage tank, and the second energy storage pipe is connected to the outlet end of the energy storage tank.

7. The air conditioning system based on the energy-saving control method according to claim 5, characterized in that, The first, second, third, and fourth energy storage pipelines are each equipped with an energy storage valve with adjustable flow rate.

8. The air conditioning system based on the energy-saving control method according to claim 5, characterized in that, The energy storage tank includes an inlet main pipe and an outlet main pipe, and multiple water supply pipes are connected in parallel between the inlet main pipe and the outlet main pipe. At least one water tank unit is connected in series on each water supply pipe.

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