Method for determining energy efficiency of a refrigeration plant room

Abstract

This application provides a method for determining the energy efficiency of a chiller room, relating to the field of chiller room technology, for accurately calculating the energy efficiency ratio (EER) of a chiller room under different operating strategies. The method includes: acquiring the energy consumption model of the chiller room and the operating strategy selected by the user; determining the operating parameters of the chiller room according to the operating strategy; determining the chilled water flow rate, chilled water return temperature, first condensing load, cooling water flow rate, and cooling water supply temperature based on hourly cooling load, chilled water supply and return temperature, chilled water supply temperature, preset condensing load, cooling water supply and return temperature, and cooling water return temperature; and calculating the EER of the chiller room based on the first condensing load, chilled water flow rate, cooling water flow rate, cooling water supply and return temperature, cooling water return temperature, and the energy consumption model.

Description

Technical Field

[0001] This application relates to the field of refrigeration room technology, and in particular to a method for determining the energy efficiency of a refrigeration room. Background Technology

[0002] Currently, refrigeration rooms are widely used in commercial and civil buildings. With the continuous development of high-efficiency refrigeration room systems, in order to improve the overall operating energy efficiency of refrigeration rooms, project manufacturers usually conduct energy efficiency simulations during the design phase to design the most energy-efficient operating strategy.

[0003] However, most energy efficiency simulations of chiller rooms are conducted by simulating and analyzing the energy efficiency of chiller rooms through pre-set operating strategies. The simulation results deviate significantly from the actual operating results of the chiller room, thus failing to provide accurate and reliable operating strategies and causing considerable misleading effects on the design of chiller rooms. Summary of the Invention

[0004] This application provides a method for determining the energy efficiency of a chiller room, which is used to accurately calculate the energy efficiency ratio of the chiller room under different operating strategies.

[0005] To achieve the above objectives, this application adopts the following technical solution.

[0006] In a first aspect, embodiments of this application provide a method for determining the energy efficiency of a chiller room. The method includes: acquiring an energy consumption model of the chiller room and a user-selected operating strategy; determining operating parameters of the chiller room based on the operating strategy; wherein the operating parameters include: hourly cooling load, chilled water supply and return temperature difference, chilled water supply temperature, preset condensing load, cooling water supply and return temperature difference, and cooling water return temperature; determining chilled water flow rate, chilled water return temperature, a first condensing load, cooling water flow rate, and cooling water supply temperature based on the hourly cooling load, chilled water supply and return temperature difference, chilled water supply temperature, preset condensing load, cooling water supply and return temperature difference, and cooling water return temperature; and calculating the energy efficiency ratio of the chiller room based on the first condensing load, chilled water flow rate, cooling water flow rate, cooling water supply and return temperature difference, cooling water return temperature, and the energy consumption model.

[0007] The technical solution provided in this application provides at least the following beneficial effects: This application provides a method for determining the energy efficiency of a chiller room. Users can select an operating strategy, and based on the user-selected operating strategy, the operating parameters of the chiller room are determined. Then, based on these operating parameters, the chilled water flow rate, the first condensing load, the cooling water flow rate, and the cooling water supply temperature are determined. Furthermore, based on the energy consumption model of the chiller room, the chilled water flow rate, the first condensing load, the cooling water flow rate, and the cooling water supply temperature, the energy efficiency ratio of the chiller room is calculated. It is understood that users can select different operating strategies, and thus can calculate the energy efficiency ratios of multiple chiller rooms. Therefore, by calculating the energy efficiency ratios of chiller rooms under different operating strategies, the design of the chiller room can be accurately guided.

[0008] In some embodiments, the energy consumption model of the chiller room includes the energy consumption model of the chiller unit, the energy consumption model of the chilled water pump, the energy consumption model of the cooling water pump, and the energy consumption model of the cooling tower.

[0009] In some embodiments, the method includes: determining the chilled water flow rate and chilled water return temperature based on hourly cooling load, chilled water supply and return temperature difference, and chilled water supply temperature; calculating the chilled water flow rate for each chiller unit based on the chilled water flow rate; calculating the chilled water supply temperature for each chiller unit based on the chilled water flow rate and chilled water return temperature; and iteratively calculating the second condensing load using an energy consumption model based on the cooling water return temperature and the chilled water supply temperature for each chiller unit.

[0010] In some embodiments, the method includes: using an energy consumption model to iteratively calculate a third condensing load based on the cooling water return temperature and the chilled water supply temperature of each chiller unit; and determining the third condensing load as the second condensing load when the relative error between the third condensing load and the first condensing load is less than a preset threshold.

[0011] In some embodiments, the chilled water supply temperature of each chiller unit satisfies the following relationship:

[0012]

[0013] Among them, t chw，s，i The chilled water supply temperature for each chiller unit; t chw，r Q is the chilled water return temperature; e，i The cooling load rate for each chiller unit; m chwi Let i be the chilled water flow rate for each chiller unit; i = 1, 2, ..., n, where n is a positive integer.

[0014] In some embodiments, the chilled water flow rate satisfies the following relationship:

[0015]

[0016] Where, m chw Q is the chilled water flow rate; e Δt represents the hourly cooling load; c represents the specific heat capacity of water; Δt chw The temperature difference between the supply and return water for chilled water.

[0017] In some embodiments, the method includes: calculating the energy consumption of a chiller unit based on a second condensing load; inputting chilled water flow rate into an energy consumption model of a chilled water pump and outputting the energy consumption of the chilled water pump; inputting cooling water flow rate into an energy consumption model of a cooling water pump and outputting the energy consumption of the cooling water pump; inputting the cooling water supply and return temperature difference and the cooling water return temperature into an energy consumption model of a cooling tower and outputting the energy consumption of the cooling tower; and calculating the energy efficiency ratio of the chiller room based on the energy consumption of the chiller unit, the energy consumption of the chilled water pump, the energy consumption of the cooling water pump, and the energy consumption of the cooling tower.

[0018] In some embodiments, the operating strategy includes: a strategy for the number of chillers, chilled water pumps, cooling water pumps, and cooling towers to be turned on; a strategy for allocating the cooling load rate of chillers; a strategy for controlling the frequency of chilled water pumps and cooling water pumps; and a strategy for setting the chilled water supply temperature, the chilled water supply-return temperature difference, the cooling water return temperature, and the cooling water supply-return temperature difference. The frequency control strategy includes a variable frequency control strategy and a fixed frequency control strategy, and the setting strategy includes a constant temperature control strategy and a variable temperature control strategy.

[0019] In some embodiments, the hourly cooling load is the hourly cooling load for the entire year of 8760 hours, calculated based on simulations of the target building.

[0020] In some embodiments, the method further includes: collecting operating data of the chiller room; wherein the operating data includes outdoor wet-bulb temperature, evaporation temperature of the evaporator, chilled water supply temperature, chilled water return temperature, chilled water flow rate, condensation temperature of the condenser, cooling water supply temperature, cooling water return temperature, cooling water flow rate, cooling load, energy efficiency ratio, chilled water supply temperature of the chiller unit, operating power and cooling water flow rate of the chilled water pump, operating power and chilled water flow rate of the cooling water pump, outlet water temperature, inlet water temperature and operating power of the cooling tower; and establishing an energy consumption model for the chiller unit, chilled water pump, cooling water pump and cooling tower based on the operating data and the least squares method.

[0021] Secondly, embodiments of this application provide an energy efficiency determination apparatus for a chiller room. This computing device is used to execute the energy efficiency determination method for a chiller room provided in the first aspect. The computing device may be an electronic device with data processing capabilities, or a functional module within that electronic device.

[0022] Thirdly, embodiments of this application provide a controller, including: one or more processors; one or more memories; wherein the one or more memories are used to store computer program code, the computer program code including computer instructions, and when the one or more processors execute the computer instructions, the controller executes any of the energy efficiency determination methods for refrigeration rooms provided in the first aspect.

[0023] Fourthly, embodiments of this application provide a computer-readable storage medium including computer instructions that, when executed on a computer, cause the computer to perform any of the energy efficiency determination methods for a cooling room provided in this application.

[0024] Fifthly, embodiments of the present invention provide a computer program product that can be directly loaded into a memory and contains software code. After being loaded and executed by a computer, the computer program product can realize any of the energy efficiency determination methods for refrigeration rooms provided in the first aspect.

[0025] It should be noted that the aforementioned computer instructions may be stored, in whole or in part, on a computer-readable storage medium. This computer-readable storage medium may be packaged together with the controller's processor, or it may be packaged separately from the controller's processor; this application does not impose any limitations on this.

[0026] The beneficial effects described in aspects two through five of this application can be referred to the analysis of the beneficial effects of aspect one, and will not be repeated here. Attached Figure Description

[0027] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of the present invention and do not constitute a limitation on the technical solutions of the present invention.

[0028] Figure 1 This application provides a schematic diagram of the structure of a refrigeration room.

[0029] Figure 2 A schematic diagram of the refrigeration cycle principle of a refrigeration room is provided as an embodiment of this application;

[0030] Figure 3 A flowchart illustrating a method for determining the energy efficiency of a refrigeration room, provided as an embodiment of this application;

[0031] Figure 4 An hourly cooling load data graph provided for an embodiment of this application;

[0032] Figure 5 A flowchart illustrating another method for determining the energy efficiency of a refrigeration room, provided as an embodiment of this application;

[0033] Figure 6 A flowchart illustrating an iterative calculation method for condensation load provided in this application embodiment;

[0034] Figure 7 A schematic diagram of the energy efficiency ratio of a refrigeration room provided in an embodiment of this application;

[0035] Figure 8 A schematic diagram illustrating the energy efficiency ratio of another refrigeration room provided in this application embodiment;

[0036] Figure 9 A schematic diagram illustrating the energy consumption ratio of a refrigeration room, provided as an embodiment of this application;

[0037] Figure 10 A schematic diagram illustrating the energy consumption percentage of another refrigeration room provided in an embodiment of this application;

[0038] Figure 11 A schematic diagram illustrating the energy consumption percentage of another refrigeration room provided in an embodiment of this application;

[0039] Figure 12 A schematic diagram illustrating the relative error of the energy efficiency ratio of a refrigeration room, provided as an embodiment of this application;

[0040] Figure 13 A flowchart illustrating another method for determining the energy efficiency of a refrigeration room, provided as an embodiment of this application;

[0041] Figure 14 A schematic diagram illustrating the relative error of the energy efficiency ratio of a chiller unit, provided for an embodiment of this application;

[0042] Figure 15 A schematic diagram illustrating the relative error of energy consumption during operation of a chiller unit, provided for an embodiment of this application;

[0043] Figure 16 A schematic diagram illustrating the relative error of the operating energy consumption of a chilled water pump and a cooling water pump, provided for embodiments of this application;

[0044] Figure 17 A schematic diagram illustrating the relative error of the operating energy consumption of another chilled water pump and cooling water pump provided in an embodiment of this application;

[0045] Figure 18 A schematic diagram illustrating the relative error of cooling tower operating energy consumption provided in an embodiment of this application;

[0046] Figure 19 A schematic diagram illustrating the relative error of cooling tower operating energy consumption, provided as an embodiment of this application;

[0047] Figure 20 A flowchart illustrating another method for determining the energy efficiency of a refrigeration room, provided as an embodiment of this application. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0050] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0051] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, when describing pipelines, the terms "connected" and "linked" as used in this application have the meaning of establishing electrical connection. The specific meaning needs to be understood in conjunction with the context.

[0052] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0053] Currently, energy efficiency simulations for chiller rooms mostly involve building predictive models, calculating using a pre-defined operating strategy, and training the models with simulated data to obtain simulation results. However, due to limitations in the simulated data, the simulation results often lack realism. Furthermore, because the operating strategy for chiller rooms cannot be customized, it cannot effectively guide the construction of chiller rooms.

[0054] Based on this, this application provides a method for determining the energy efficiency of a chiller room. The user can select an operating strategy, and based on the selected strategy, the operating parameters of the chiller room are determined. Then, based on these operating parameters, the chilled water flow rate, the first condensing load, the cooling water flow rate, and the cooling water supply temperature are determined. Furthermore, based on the chiller room's energy consumption model, chilled water flow rate, first condensing load, cooling water flow rate, and cooling water supply temperature, the energy efficiency ratio (EER) of the chiller room is calculated. Thus, by calculating the EER of the chiller room under different operating strategies, the design of the chiller room can be accurately guided.

[0055] Figure 1 This is a schematic diagram illustrating the composition of a refrigeration room according to an exemplary embodiment of this application. Figure 1 As shown, the refrigeration room 100 includes multiple chiller units 101 and a water distributor 102. Figure 1 (not shown in the image), water collector 103 ( Figure 1 (not shown in the image) Multiple chilled water pumps 104, multiple cooling water pumps 105, and multiple cooling towers 106.

[0056] The chilled water circuit is formed by sequentially connecting at least one chiller unit 101, at least one water distributor 102, at least one water collector 103, and at least one chilled water pump 104; the cooling water circuit is formed by sequentially connecting at least one chiller unit 101, at least one cooling water pump 105, and at least one cooling tower 106.

[0057] In some embodiments, the chiller unit 101 is used to cool the passing chilled water.

[0058] In some embodiments, such as Figure 2 As shown, the chiller unit 101 includes a compressor 11, a condenser 12, an evaporator 13, and a throttling device 14. The compressor 11, condenser 12, evaporator 13, and throttling device 14 are sequentially connected to form a refrigerant circulation loop. It should be noted that in this embodiment, the sequential connection only indicates the order of connection between the various components; other components may also be included between them. For example, a shut-off valve may be installed on the pipeline between the compressor 11 and the condenser 12.

[0059] In some embodiments, compressor 11 may be a centrifugal compressor, screw compressor, scroll compressor, etc. Compressor 11 is used to increase the pressure of refrigerant in the refrigeration room, so that the refrigerant circulates in the refrigeration room to achieve the purpose of refrigeration.

[0060] In some embodiments, the condenser 12 can be a shell-and-tube condenser, a spiral plate condenser, or a strip condenser, etc. The working principle of the condenser 12 is that after the high-pressure superheated gaseous refrigerant from the refrigeration compressor enters the condenser 12, it transfers heat to the surrounding air, or first transfers heat to water, and then the water transfers heat to the surrounding air. While the refrigerant releases heat in the condenser 12, it condenses into a liquid due to cooling.

[0061] In some embodiments, the evaporator 13 can be a shell-and-tube evaporator, a water tank evaporator, etc. The working principle of the evaporator 13 is that the liquid refrigerant absorbs the heat energy of the object being cooled by water in the evaporator 13 and evaporates into gaseous refrigerant.

[0062] In some embodiments, the throttling device 14 may be a thermostatic expansion valve. The throttling device 14 is located at the outlet of the condenser 12 and the inlet of the evaporator 13, and is used to reduce the condensing pressure of the refrigerant to the evaporating pressure.

[0063] In some embodiments, the inlet of the water distributor 102 is connected to the outlet of the chiller unit 101, and the outlet of the water distributor 102 is connected to the cooling equipment, for distributing chilled water flow to each branch to achieve pressure equalization.

[0064] In some embodiments, the inlet of the water collector 103 is connected to the cooling equipment, and the outlet of the water collector 103 is connected to the chilled water pump 104 via a chilled water pump valve, for collecting chilled water from each branch. The chilled water pump valve is used to control the flow rate of chilled water in the pipeline.

[0065] In some embodiments, the water distributor 102 and the water collector 103 are connected to the cooling equipment via connecting pipes. Chilled water flows from the outlet end of the water distributor 102 through the connecting pipes through the cooling equipment, and then enters the water collector 103 from the inlet end of the water collector 103 through the connecting pipes.

[0066] In some embodiments, multiple chilled water pumps 104 are connected in parallel. The first end of the chilled water pump 104 is connected to the inlet end of the chiller unit 101, and the second end of the chilled water pump 104 is connected to the outlet end of the water collector 103. This is used to circulate chilled water, so that the chilled water can exchange heat with the indoor air to reduce the temperature of the indoor air, thereby achieving the effect of cooling.

[0067] In some embodiments, multiple cooling water pumps 105 are connected in parallel. A first end of each cooling water pump 105 is connected to the outlet end of the chiller unit 101, and a second end of each cooling water pump 105 is connected to the first end of the cooling tower 106. The cooling water pumps 105 circulate cooling water. After the chilled water removes heat from the room, the chilled water in the chiller unit 101 transfers heat to the cooling water. The cooling water pumps 105 pressurize the heated cooling water into the cooling tower 106, allowing the heated cooling water to exchange heat with the atmosphere. Further, after cooling, the cooling water is returned to the condenser 12 in the chiller unit 101 to continue heat exchange.

[0068] In some embodiments, the cooling water pump 105 further includes a cooling water pump valve for controlling the opening degree of the cooling water pump valve to control the flow rate of cooling water in the pipeline.

[0069] In some embodiments, the second end of the cooling tower 106 is connected to the inlet end of the chiller unit 101 to disperse the heat in the water, dissipate the heat through airflow so that the water temperature is reduced, and then the cooling water is recycled.

[0070] This application also provides an energy efficiency determination device for a chiller room (hereinafter referred to as the determination device for ease of description), which is used to execute the above-described energy efficiency determination method for a chiller room. The determination device can be an electronic device with data processing capabilities, or a functional module within that electronic device; there is no limitation on this. For example, the electronic device can be a server, which can be a single server or a server cluster composed of multiple servers. Another example is that the electronic device can be a mobile phone, tablet computer, desktop computer, laptop computer, handheld computer, notebook computer, ultra-mobile personal computer (UMPC), netbook, as well as cellular phones, personal digital assistants (PDAs), augmented reality (AR) / virtual reality (VR) devices, and other terminal devices. This disclosure does not impose any special limitations on the specific form of the electronic device.

[0071] The embodiments provided in this application will now be described in detail with reference to the accompanying drawings.

[0072] like Figure 3 As shown in the figure, this application provides a method for determining the energy efficiency of a chiller room, which includes the following steps:

[0073] S101. Obtain the energy consumption model of the chiller room and the operating strategy selected by the user.

[0074] In some embodiments, the energy consumption model of the chiller room includes the energy consumption model of the chiller unit, the energy consumption model of the chilled water pump, the energy consumption model of the cooling water pump, and the energy consumption model of the cooling tower.

[0075] In some embodiments, the operating strategies include strategies for the number of chillers, chilled water pumps, cooling water pumps, and cooling towers in operation; strategies for allocating the cooling load rate of chillers; strategies for controlling the frequency of chilled water pumps, cooling water pumps, and cooling towers; and strategies for setting the chilled water supply temperature, the chilled water supply-return temperature difference, the cooling water return temperature, and the cooling water supply-return temperature difference. The frequency control strategies include variable frequency control and fixed frequency control strategies, and the setting strategies include constant temperature control and variable temperature control strategies.

[0076] In some embodiments, the operating strategy also includes the selection of equipment such as chillers, chilled water pumps, cooling water pumps, and cooling towers.

[0077] For example, the refrigeration room includes two chiller units, three cooling water pumps, three chilled water pumps, and two cooling towers. The chiller units have a rated cooling capacity of 1406 kW, a rated power of 22.6 kW, and a chilled water flow rate of 242 m³ / h. 3 / h, cooling water flow rate is 303m³ / h 3 / h. The selected chilled water pump model is CHP-B1, with a chilled water flow rate of 266.5 m³ / h. 3 The pump has an input power of 27kW, a head of 32m, and an efficiency of 75%. The selected cooling water pump model is CWP-B1, with a cooling water flow rate of 332.5m³ / h. 3 The cooling tower has an input power of 37kW, a head of 26m, and an efficiency of 85%. The selected cooling tower is a CT-FR ultra-low noise crossflow cooling tower with a processing capacity of 365m³ / h. 3 / h, each cooling tower includes two fans, each with a power of 7.5kW.

[0078] The user-selected primary operating strategy includes the following: The chiller unit activation strategy is to start one chiller unit first, and then start the other chiller unit when its cooling load reaches its rated cooling load. The chilled water pump, cooling water pump, and cooling tower activation strategy is to start all chillers / cooling water pumps and cooling towers when the chillers start, and shut them down when the chillers stop. The chiller unit cooling load allocation strategy is based on the chiller unit activation strategy, allocating a cooling load rate to each chiller unit. For example, if two chillers are running simultaneously, one chiller unit will have a 100% cooling load rate, while the other chiller unit will handle the remaining cooling load at 30%. The chilled water pump, cooling water pump, and cooling tower frequency control strategy is a fixed-frequency control strategy. The setting strategy for chilled water supply temperature, chilled water supply-return temperature difference, cooling water return temperature, and cooling water supply-return temperature difference is a constant temperature control strategy. For example, the set value for chilled water supply temperature is always 7℃, the set value for chilled water supply-return temperature difference is always 5℃, the set value for cooling water return temperature is always 26℃, and the set value for cooling water supply-return temperature difference is always 5℃.

[0079] The user-selected second operating strategy includes: an equal cooling load allocation strategy for chiller units; a chiller unit activation strategy based on the highest energy efficiency ratio determined by the equal cooling load allocation strategy; a chilled water pump activation strategy that meets the chilled water flow requirements of the chiller units; a cooling water pump activation strategy that meets the cooling water flow requirements of the chiller units; and a cooling tower activation strategy that selects an appropriate number of cooling towers to operate, provided the cooling capacity meets the load requirements of the refrigerated equipment. The frequency control strategy for chilled water pumps, cooling water pumps, and cooling towers is a variable frequency drive (VFD) strategy. The setting strategies for chilled water supply temperature, chilled water supply-return temperature difference, cooling water return temperature, and cooling water supply-return temperature difference are variable temperature control strategies, which can be optimized in real time based on the operating conditions of the chiller room.

[0080] In some embodiments, the operating strategy also includes the selection of equipment such as chillers, chilled water pumps, cooling water pumps, and cooling towers.

[0081] For example, the third operating strategy selected by the user may include the chilled water pumps shown in Table 1 below, the cooling water pumps shown in Table 2 below, and the cooling towers shown in Table 3 below.

[0082] Table 1

[0083]

[0084] Table 2

[0085]

[0086] Table 3

[0087]

[0088]

[0089] S102. Determine the operating parameters of the refrigeration room according to the operating strategy.

[0090] The operating parameters of the refrigeration room include hourly cooling load, chilled water supply and return temperature difference, chilled water supply temperature, first condensing load, cooling water supply and return temperature difference, and cooling water return temperature.

[0091] Among them, hourly cooling load is used to characterize the cooling capacity of the refrigeration room at various time periods, such as the cooling capacity from 0:00 to 1:00, the cooling capacity from 1:00 to 2:00, ... the cooling capacity from 23:00 to 24:00. The above cooling capacity is the hourly cooling load.

[0092] In some embodiments, the hourly cooling load is the hourly cooling load for the entire year (8760 hours) calculated based on simulations of the target building. For example, if the target building is a hotel building, such as... Figure 4 As shown, the hourly cooling load is the hourly cooling load for the entire year of 8760 hours, calculated based on the simulation of the hotel building.

[0093] S103. Based on the hourly cooling load, chilled water supply and return water temperature difference, chilled water supply temperature, first condensing load, cooling water supply and return water temperature difference, and cooling water return temperature, determine the chilled water flow rate, chilled water return temperature, second condensing load, cooling water flow rate, and cooling water supply temperature.

[0094] In some embodiments, the first cooling water flow rate is determined based on the first condensing load and the temperature difference between the cooling water supply and return water.

[0095] The first cooling water flow rate can be obtained from the following formula (1):

[0096]

[0097] Where, m cw For example, the cooling water flow rate, m cw Q is the first cooling water flow rate; c For condensation load, for example, Q c Δt represents the preset condensation load; c represents the specific heat capacity of water; Δt cw The temperature difference between the supply and return water for cooling.

[0098] Optional, preset condensing load Q c It is 1.2 times the current hourly cooling load.

[0099] In some embodiments, the sum of the cooling water supply and return water temperature difference and the cooling water return water temperature can also be used as the cooling water supply temperature. The cooling water supply temperature can be obtained from the following formula (2):

[0100] t cw，s =t cw，r +Δt cw Formula (2)

[0101] Among them, t cw，s The cooling water supply temperature; t cw，r Δt represents the return temperature of the cooling water. cw Cooling water supply and return water temperature difference.

[0102] In some embodiments, such as Figure 5 As shown, step S103 includes the following steps:

[0103] S1031. Determine the chilled water flow rate and chilled water return temperature based on the hourly cooling load, the temperature difference between the chilled water supply and return water, and the chilled water supply temperature.

[0104] In some embodiments, the chilled water flow rate is determined based on the hourly cooling load and the temperature difference between the chilled water supply and return water. The chilled water flow rate is obtained from the following formula (3):

[0105]

[0106] Where, m chw Q is the chilled water flow rate; e Δt represents the hourly cooling load; c represents the specific heat capacity of water; Δt chw The temperature difference between the supply and return water for chilled water.

[0107] Understandably, this chilled water flow rate is the total chilled water flow rate.

[0108] In some embodiments, the sum of the chilled water supply and return water temperature difference and the chilled water supply temperature is used as the chilled water return water temperature. The chilled water return water temperature can be obtained from the following formula (4):

[0109] t chw，r =t chw，s +Δt chw Formula (4)

[0110] Among them, t chw，r t is the temperature of the chilled water return. chw，s Δt represents the chilled water supply temperature. chw Temperature difference between chilled water supply and return water.

[0111] S1032. Calculate the chilled water flow rate for each chiller unit based on the chilled water flow rate.

[0112] In some embodiments, the allocation ratio of chilled water flow for each chiller unit is determined according to the cooling load rate allocation strategy selected by the user. Further, the chilled water flow rate for each chiller unit is calculated based on this allocation ratio and the chilled water flow rate. The chilled water flow rate for each chiller unit can be obtained from the following formula (5):

[0113] m chw =A1m chw1 +A2m chw2 +…+A i m chwi Formula (5)

[0114] Where, m chw This represents the total flow rate of chilled water; A1, A2…A i The allocation ratio of chilled water flow rate for each chiller unit; m chw1 m chw2 ... m chwi Let i be the chilled water flow rate for each chiller unit; i = 1, 2, ..., n, where n is a positive integer.

[0115] S1033. Calculate the chilled water supply temperature of each chiller unit based on the chilled water flow rate and chilled water return temperature of each chiller unit.

[0116] In some embodiments, the chilled water supply temperature of each chiller unit is calculated based on the chilled water flow rate and chilled water return temperature of each chiller unit. The chilled water supply temperature of each chiller unit can be obtained from the following formula (6):

[0117]

[0118] Among them, t chw，s，i The chilled water supply temperature for each chiller unit; t chw，r Q is the chilled water return temperature; e，i The cooling load rate for each chiller unit; m chwi Let i be the chilled water flow rate for each chiller unit; i = 1, 2, ..., n, where n is a positive integer.

[0119] Understandable, chilled water return temperature t chw，r This refers to the return water temperature of each chiller unit.

[0120] S1034. Based on the cooling water return temperature and the chilled water supply temperature of each chiller unit, the second condensing load is obtained by iterative calculation using the energy consumption model.

[0121] In some embodiments, the energy consumption of each chiller unit is obtained using the energy consumption model of the chiller unit based on the cooling water return temperature, the chilled water supply temperature of each chiller unit, the hourly cooling load, the chilled water flow rate, and the first cooling water flow rate mentioned above. Furthermore, the third condensing load is iteratively calculated based on the energy consumption of each chiller unit and the hourly cooling load.

[0122] In some embodiments, when the relative error between the third condensing load and the first condensing load is less than a preset threshold, the third condensing load is determined as the second condensing load.

[0123] Optionally, the preset threshold is set by the administrator and is not limited thereto. For example, the preset threshold could be 3%.

[0124] In some embodiments, the relative error between the second condensing load and the preset condensing load can be obtained by the following formula (7):

[0125]

[0126] Where γ is the relative error value between the second condensing load and the first condensing load; Q c，n+1 For the second condensing load; Q c，n This is the preset condensation load.

[0127] In some embodiments, when the relative error between the third condensing load and the first condensing load is greater than or equal to a preset threshold, the third condensing load is determined as the first condensing load. Then, based on the newly determined first condensing load and the temperature difference between the cooling water supply and return water, the cooling water flow rate is determined, and the above steps S1031 to S1034 are continued until the relative error between the third condensing load and the first condensing load is less than the preset threshold.

[0128] In some embodiments, the final cooling water flow rate is determined based on the second condensation load.

[0129] The following is combined with, for example Figure 6 The logic block diagram shown exemplifies the complete process of iteratively calculating the second condensation load:

[0130] S1. Determine the first cooling water flow rate based on the first condensation load.

[0131] S2. Determine the chilled water flow rate and chilled water return temperature based on the hourly cooling load, the temperature difference between the chilled water supply and return water, and the chilled water supply temperature.

[0132] S3. Calculate the chilled water flow rate for each chiller unit based on the chilled water flow rate.

[0133] S4. Calculate the chilled water supply temperature for each chiller unit based on the chilled water flow rate and chilled water return temperature of each chiller unit.

[0134] S5. Based on the cooling water return temperature, the chilled water supply temperature of each chiller unit, and the first cooling water flow rate mentioned above, the third condensing load is calculated iteratively.

[0135] Determine whether the relative error between the third condensing load and the first condensing load is less than a preset threshold.

[0136] If so, proceed to step S6.

[0137] If not, proceed to step S7 and continue to proceed to steps S1 to S5 until the relative error between the third condensing load and the first condensing load is less than the preset threshold.

[0138] S6. The third condensing load is determined as the second condensing load.

[0139] S7. The third condensing load is determined as the first condensing load.

[0140] S104. Based on the first condensing load, chilled water flow rate, cooling water flow rate, cooling water supply and return water temperature difference, cooling water return water temperature, and energy consumption model, calculate the energy efficiency ratio of the chiller room.

[0141] In some embodiments, the energy consumption of the chiller unit is calculated based on the first condensing load. The energy consumption of the chiller unit can be obtained from the following formula (8):

[0142] P1 = Q c -Q e Formula (8)

[0143] Where P1 is the energy consumption of the chiller unit; Q c Q is the first condensing load; e This is the hourly cooling load.

[0144] In some embodiments, the chilled water flow rate is input into the energy consumption model of the chilled water pump, and the energy consumption of the chilled water pump is output.

[0145] In some embodiments, the cooling water flow rate is input into the energy consumption model of the cooling water pump, and the energy consumption of the cooling water pump is output.

[0146] In some embodiments, the cooling water supply and return water temperature difference and the cooling water return water temperature are input into the energy consumption model of the cooling tower, and the energy consumption of the cooling tower is output.

[0147] In some embodiments, the energy efficiency ratio of the chiller room is calculated based on the energy consumption of the chiller unit, the energy consumption of the chilled water pump, the energy consumption of the cooling water pump, and the energy consumption of the cooling tower.

[0148] First, the total energy consumption of the chiller room is calculated based on the energy consumption of the chiller unit, the chilled water pump, the cooling water pump, and the cooling tower. The total energy consumption of the chiller room can be obtained using the following formula (9):

[0149] P a =P1+P chw +P cw +P ct Formula (9)

[0150] Among them, P a P1 represents the total energy consumption of the refrigeration room; P2 represents the energy consumption of the chiller unit; P3 represents the total energy consumption of the refrigeration room. chw Energy consumption of the chilled water pump; P cw Energy consumption of the cooling water pump; P ct This refers to the energy consumption of the cooling tower.

[0151] Furthermore, the energy efficiency ratio of the refrigeration room is calculated based on the total energy consumption of the refrigeration room.

[0152] In some embodiments, the energy efficiency ratio of the chiller room can be obtained by the following formula (10):

[0153]

[0154] Where EER is the energy efficiency ratio of the chiller room; Q e For hourly cooling load; P a This represents the total energy consumption of the refrigeration room.

[0155] For example, such as Figure 7 As shown, based on the first operating strategy selected by the user, the first energy efficiency ratio (EER) of the chiller room can be calculated; based on the second operating strategy, the second EER can be calculated; and based on the third operating strategy, the third EER can be calculated. The third EER is greater than the second EER each month, and the second EER is greater than the first EER. Furthermore, based on... Figure 7 The energy efficiency ratios under different operating strategies are shown below. Figure 8 As shown, the annual average energy efficiency ratio under each operating strategy can be obtained. Among them, the third energy efficiency ratio is greater than the second energy efficiency ratio, and the second energy efficiency ratio is greater than the first energy efficiency ratio.

[0156] In addition, based on the energy consumption of the chiller unit, the energy consumption of the chilled water pump, the energy consumption of the cooling water pump, and the energy consumption of the cooling tower, the percentages of the energy consumption of the chiller unit, the energy consumption of the chilled water pump, the energy consumption of the cooling water pump, and the energy consumption of the cooling tower in the total energy consumption of the refrigeration room are obtained. Figure 9This shows the energy consumption percentage of the chiller room under the first operating strategy selected by the user. Figure 10 This shows the energy consumption percentage of the chiller room under the second operating strategy mentioned above, selected by the user. Figure 11 The data shows the energy consumption percentage of the chiller room under the third operating strategy selected by the user.

[0157] It should be noted that, in order to verify the accuracy of the above-mentioned method for determining the energy efficiency of the chiller room, such as... Figure 12 As shown, in this embodiment of the application, the actual energy efficiency ratio of the refrigeration room is calculated by collecting 1,000 sets of real-time operating data. The relative error between the actual energy efficiency ratio of the refrigeration room and the energy efficiency ratio obtained by the above-mentioned energy efficiency determination method is mostly within (-5%, 5%), and the relative error is small.

[0158] based on Figure 5 The illustrated embodiment of this application provides a method for determining the energy efficiency of a chiller room. A user can select an operating strategy. Based on the user-selected operating strategy, the operating parameters of the chiller room are determined. Then, based on these operating parameters, the chilled water flow rate, the first condensing load, the cooling water flow rate, and the cooling water supply temperature are determined. Further, based on the energy consumption model of the chiller room, the chilled water flow rate, the first condensing load, the cooling water flow rate, and the cooling water supply temperature, the energy efficiency ratio (EER) of the chiller room is calculated. It is understood that the user can select different operating strategies, thereby calculating the EER of multiple chiller rooms. Thus, by calculating the EER of chiller rooms under different operating strategies, the design of the chiller room can be accurately guided.

[0159] In some embodiments, such as Figure 13 As shown, the determination method also includes the following steps:

[0160] S201. Collect operating data of the refrigeration room.

[0161] The operating data includes the evaporation temperature of the evaporator, the chilled water supply temperature, the chilled water return temperature, and the chilled water flow rate; the condensation temperature of the condenser, the condensation load, the cooling water supply temperature, the cooling water return temperature, and the cooling water flow rate; the cooling load, energy efficiency ratio, and chilled water supply temperature of the chiller unit; the operating power and cooling water flow rate of the chilled water pump; the operating power and chilled water flow rate of the cooling water pump; and the outlet water temperature, inlet water temperature, and operating power of the cooling tower.

[0162] In some embodiments, the cooling load of the chiller unit is determined based on the specific heat capacity of water, the chilled water flow rate, the chilled water return temperature, and the chilled water supply temperature in the operating data.

[0163] The cooling load of the chiller unit can be obtained from the following formula (11):

[0164]

[0165] Among them, Q d ρ is the cooling load of the chiller unit; c is the specific heat capacity of water; m e T is the chilled water flow rate; e-rtn T represents the chilled water return temperature. e-sup This refers to the temperature of the chilled water supply.

[0166] In some embodiments, the condensing load of the chiller unit is determined based on the specific heat capacity of water, the cooling water flow rate, the cooling water supply temperature, and the cooling water return temperature in the operating data.

[0167] The condensing load of the chiller unit can be obtained from the following formula (12):

[0168] Q c =c×m c ×(T c-sup -T c-rtn ) Formula (12)

[0169] Among them, Q c For the condensing load of the chiller unit; m c T is the cooling water flow rate; c-sup T represents the cooling water supply temperature. c-rtn This refers to the cooling water return temperature.

[0170] In some embodiments, considering that the collected operating data may contain errors, it is also necessary to remove abnormal operating data to make the operating data more accurate, thereby reducing the interference of abnormal data groups on the establishment of the chiller unit energy consumption model and laying the foundation for improving the accuracy of the chiller unit energy consumption model in the future.

[0171] In one possible implementation, the load imbalance rate can be determined based on the chiller's cooling load, condensing load, and operating power. If the load imbalance rate is greater than or equal to a preset load imbalance rate, the operating data corresponding to that load imbalance rate is discarded to reduce data acquisition errors.

[0172] For example, the load imbalance rate can be obtained from the following formula (13):

[0173]

[0174] Among them, B a P represents the load imbalance rate. w This refers to the operating power of the chiller unit.

[0175] S202. Based on the operating data and the least squares method, establish the energy consumption model of the chiller unit, chilled water pump, cooling water pump and cooling tower.

[0176] In some embodiments, the evaporation temperature and condensation temperature of the chiller unit are calculated based on the evaporation temperature of the evaporator, the chilled water supply temperature, the chilled water return temperature, the chilled water flow rate, the condensation temperature of the condenser, the condensation load, the cooling water supply temperature, the cooling water return temperature, and the cooling water flow rate.

[0177] Furthermore, based on the evaporation and condensation temperatures of the chiller unit, the cooling load of the chiller unit, and the energy efficiency ratio, the relationship between the energy efficiency ratio of the chiller unit and the evaporation and condensation temperatures of the chiller unit is obtained by fitting using the least squares method.

[0178] The energy efficiency ratio of the chiller unit can be obtained by the following formula (14):

[0179]

[0180] Where COP is the energy efficiency ratio of the chiller unit; A1, B1, and C1 are fitting coefficients; and PLR is the ratio of the chiller unit's cooling load to its rated load.

[0181] For example, based on actual operating data, the fitting coefficient A is -0.6578; the fitting coefficient B is 0.8922; and the fitting coefficient C is 0.3294.

[0182] Furthermore, an energy consumption model for the chiller unit is established based on its energy efficiency ratio and cooling load.

[0183] The energy consumption model of the chiller unit is obtained from formula (15):

[0184]

[0185] Where P is the operating power of the chiller unit, which is also the operating energy consumption of the chiller unit.

[0186] It should be noted that, in order to verify the accuracy of the energy consumption model of the above chiller unit, such as Figure 14 and Figure 15 As shown, the actual energy efficiency ratio and actual operating power of the chiller unit calculated by the embodiment of this application through 1000 sets of real-time operating data have a small relative error with the energy efficiency ratio and operating power obtained by the energy consumption model of the chiller unit described above.

[0187] Optionally, the calculation process for the evaporation temperature and condensation temperature of the chiller unit is explained in detail below:

[0188] (1) Condensation temperature of the chiller unit

[0189] In some embodiments, the logarithmic mean temperature difference of the condenser is determined based on the temperature difference between the cooling water supply temperature and the condenser condensing temperature, and the temperature difference between the cooling water return temperature and the condenser condensing temperature.

[0190] In some embodiments, the logarithmic mean temperature difference of the condenser can be obtained by the following formulas (16) and (17):

[0191]

[0192] Δt ch，c =Δt c2 -Δt c1 Formula (17)

[0193] Where, Δt m，c The logarithmic mean temperature difference of the condenser; Δt c1 Δt is the temperature difference between the cooling water return temperature and the condenser condensing temperature. c2 Δt is the temperature difference between the cooling water supply temperature and the condenser condensing temperature. ch，c This represents the temperature difference between the inlet and outlet of the condenser.

[0194] In some embodiments, the heat transfer coefficient of the condenser is determined based on the condensing load and the logarithmic mean temperature difference of the condenser.

[0195] The heat transfer coefficient of the condenser can be obtained from the following formula (18):

[0196]

[0197] Among them, K c F c The heat transfer coefficient of the condenser.

[0198] Furthermore, based on the cooling water flow rate and condensing load, the relationship between the condenser heat transfer coefficient and the cooling water flow rate and condensing load is obtained by fitting using the least squares method.

[0199] The relationship between the condenser heat transfer coefficient and the cooling water flow rate and condensing load is shown in the following formula (19):

[0200] K c F c =a1m c 2 +b1m c ×Q c +c1m c 2 +d1m c +e1Q c +f1 formula(19)

[0201] Among them, K c F cdenoted as condenser heat transfer coefficient; a1, b1, c1, d1, e1, f1 are fitting coefficients; m c Q represents the cooling water flow rate. c This is the condensation load.

[0202] For example, based on actual operating data, the fitting coefficient a1 is -0.365; the fitting coefficient b1 is -0.0111; the fitting coefficient c1 is -0.000239; the fitting coefficient d1 is 69.4; the fitting coefficient e1 is 1.26; and the fitting coefficient f1 is -3227.177731.

[0203] In some embodiments, the condensing temperature of the chiller unit is determined based on the condenser heat transfer coefficient, condensing load, and cooling water flow rate.

[0204] The condensing temperature of the chiller unit can be obtained from the following formula (20):

[0205]

[0206] Among them, T c T is the condensing temperature of the chiller unit. c-rtn Q is the cooling water supply temperature. c ρ is the condensation load; ρ is the density of water; c is the specific heat capacity of water; K c F c The condenser heat transfer coefficient is denoted as .

[0207] (2) Evaporation temperature of the chiller unit

[0208] In some embodiments, the logarithmic mean temperature difference of the evaporator is determined based on the temperature difference between the chilled water supply temperature and the evaporator evaporation temperature, and the temperature difference between the cooling water return temperature and the evaporator evaporation temperature.

[0209] The logarithmic mean temperature difference of the evaporator can be obtained from the following formulas (21) and (22).

[0210]

[0211] Δt ch，e =Δt e2 -Δt e1 Formula (22)

[0212] Where, Δt m，e Δt is the logarithmic mean temperature difference of the evaporator. e1 Δt is the temperature difference between the chilled water return temperature and the evaporator evaporation temperature. e2 Δt is the temperature difference between the chilled water supply temperature and the evaporator evaporation temperature. ch，e This refers to the temperature difference between the inlet and outlet of the evaporator.

[0213] In some embodiments, the evaporator heat transfer coefficient is determined based on the cooling load and the logarithmic mean temperature difference of the evaporator.

[0214] The heat transfer coefficient of the evaporator can be obtained from the following formula (23):

[0215]

[0216] Among them, K e F e The heat transfer coefficient of the evaporator.

[0217] Furthermore, based on the chilled water flow rate and cooling load, the relationship between the evaporator heat transfer coefficient and the chilled water flow rate and condensation load is obtained by fitting using the least squares method.

[0218] The relationship between the evaporator heat transfer coefficient and the chilled water flow rate and condensing load is shown in the following formula (24):

[0219] K e F e =a2m e 2 +b2m e ×Q d +c2m d 2 +d2m d +e2Q d +f2 formula(24)

[0220] Where a2, b2, c2, d2, e2, and f2 are fitting coefficients.

[0221] For example, based on actual operating data, the fitting coefficient a2 is -33; the fitting coefficient b2 is -0.0048; the fitting coefficient c2 is -0.000314; the fitting coefficient d2 is 5010; the fitting coefficient e2 is 0.675; and the fitting coefficient f2 is -190311.015.

[0222] In some embodiments, the evaporation temperature of the chiller unit is determined based on the evaporator heat transfer coefficient, condensing load, and chilled water flow rate.

[0223] The evaporation temperature of the chiller unit can be obtained from the following formula (25):

[0224]

[0225] Among them, T e This refers to the evaporation temperature of the chiller unit.

[0226] In some embodiments, based on the operating energy consumption of the chilled water pump and the chilled water flow rate, the relationship between the operating energy consumption of the chilled water pump and the chilled water flow rate is obtained by fitting using the least squares method, thereby obtaining the energy consumption model of the chilled water pump.

[0227] The energy consumption model of the chilled water pump is obtained by the following formula (26):

[0228]

[0229] Among them, P chw P represents the operating power of the chilled water pump, which is also its energy consumption. chw0 The rated operating power of the chilled water pump; b0 and b1 are constant coefficients; m chw The flow rate is the chilled water flow rate; m chwe is the rated chilled water flow rate; n is the exponent.

[0230] It should be noted that, in order to verify the accuracy of the above-mentioned energy consumption model for chilled water pumps, such as... Figure 16 and Figure 17 As shown, the ratio of the actual operating power of the chilled water pump to the rated operating power of the chilled water pump, calculated by the 1000 sets of real-time operating data collected in this embodiment of the application, has a relatively small error compared with the ratio of the operating power obtained by the above-mentioned energy consumption model of the chilled water pump.

[0231] In some embodiments, based on the operating energy consumption of the cooling water pump and the cooling water flow rate, the relationship between the operating energy consumption of the cooling water pump and the cooling water flow rate is obtained by fitting using the least squares method, thereby obtaining the energy consumption model of the cooling water pump.

[0232] In some embodiments, the energy consumption model of the cooling water pump is obtained by the following formula (27):

[0233]

[0234] Among them, P cw P represents the operating power of the cooling water pump, which is also its energy consumption. cw0 The rated operating power of the cooling water pump is given by b0 and b1, which are constant coefficients; m cw The flow rate is the cooling water flow rate; m cwe is the rated cooling water flow rate; n is the exponent.

[0235] It should be noted that, in order to verify the accuracy of the above energy consumption model for the cooling water pump, such as Figure 16 and Figure 17 As shown, the actual operating power of the cooling water pump calculated by the embodiment of this application through 1000 sets of real-time operating data has a small relative error with the operating power obtained by the above-mentioned energy consumption model of the cooling water pump.

[0236] In some embodiments, the values ​​of the exponent n in the above formulas (26) and (27) are different depending on the frequency conversion control strategy. Among them, the frequency conversion control strategies include temperature difference control strategy, main pipe pressure difference control strategy, and worst-case terminal pressure difference control strategy.

[0237] Optionally, when the frequency converter control strategy is a temperature difference control strategy, the exponent n is 2. When the frequency converter control strategy is a mains differential pressure control strategy, the exponent n is 1. When the frequency converter control strategy is a worst-case terminal differential pressure control strategy, the exponent n is 1.7.

[0238] For example, when the frequency conversion control strategy is a temperature difference control strategy, based on the actual operation strategy, the constant coefficient b0 is -0.07271 and the constant coefficient b1 is 1.03675.

[0239] In some embodiments, an energy consumption model for the cooling tower is established based on the outdoor wet-bulb temperature, the cooling tower outlet water temperature, the cooling tower inlet water temperature, and the operating power.

[0240] In some embodiments, the energy consumption model of the cooling tower is obtained by the following formula (28):

[0241]

[0242] Among them, P ct P represents the operating power of the cooling tower, which is also its energy consumption, measured in kW. ct0 ΔT represents the rated power of the cooling tower; ΔT represents the actual supply and return water temperature difference; ΔT e The rated supply and return temperature difference of cooling water; T app T represents the difference between the cooling tower outlet water temperature and the outdoor wet-bulb temperature. app，e This represents the maximum difference between the actual outlet water temperature of the cooling tower and the actual outdoor wet-bulb temperature, for example, T. app，e 5℃; T wb Outdoor wet-bulb temperature; T wb，e This represents the maximum actual outdoor wet-bulb temperature, for example, T. wb，e 33℃; M cw M is the flow rate of cooling water passing through the cooling tower. cw，e is the rated water treatment capacity of the cooling tower; A, B, C, D, E, F, G, H, I, J, K, L, M, and N are fitting coefficients.

[0243] It should be noted that, in order to verify the accuracy of the above energy consumption model for cooling towers, such as... Figure 18 and Figure 19As shown, the ratio of the actual operating power of the cooling tower to the rated power of the cooling tower, calculated by the 1000 sets of real-time operating data collected in this embodiment of the application, has a relatively small error compared with the ratio of the operating power obtained by the above-mentioned energy consumption model of the cooling tower.

[0244] Furthermore, based on the aforementioned actual operating data, the following coefficients were obtained: A = 1.51801512; B = 48.87622269; C = 1.18924594; D = -4.71025092; E = -30.93754201; F = -2.51164726; and G = 0.40540141. The coefficients H, I, J, K, L, M, and N are all 35.8094937, -23.288038, -0.88203812, 18.74968127, -48.24202572, -22.03165925, 19.38739468, and 10.48545497.

[0245] In some embodiments, after establishing energy consumption models for the chiller unit, chilled water pump, cooling water pump, and cooling tower, hourly cooling load and meteorological data for 8760 hours throughout the year are input into the energy consumption model to train it. The meteorological data includes dry-bulb temperature and wet-bulb temperature.

[0246] The following is combined Figure 20 This document provides an exemplary method for determining the energy efficiency of a chiller room: First, an energy consumption model is established for the chiller unit, chilled water pump, cooling water pump, and cooling tower. Then, the energy consumption model of the chiller room and the user-selected operating strategy are obtained. Based on this operating strategy, the operating parameters of the chiller room are determined. Using the hourly cooling load, chilled water supply and return temperature difference, chilled water supply temperature, first condensing load, cooling water supply and return temperature, and cooling water return temperature from these operating parameters, the chilled water flow rate, chilled water return temperature, second condensing load, cooling water flow rate, and cooling water supply temperature are determined. Further, based on the second condensing load, chilled water flow rate, cooling water flow rate, cooling water supply and return temperature, cooling water return temperature, and the energy consumption model, the energy efficiency ratio of the chiller room is calculated.

[0247] As can be seen, the above mainly describes the solutions provided by the embodiments of this application from a methodological perspective. To achieve the above functions, the embodiments of this application provide corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should readily recognize that, in conjunction with the modules and algorithm steps of the various examples described in the embodiments disclosed herein, the embodiments of this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this invention.

[0248] This invention also provides a computer-readable storage medium, which includes computer-executable instructions. When the computer-executable instructions are executed on a computer, the computer performs a method for determining the energy efficiency of a refrigeration room as provided in the above embodiments.

[0249] This invention also provides a computer program product that can be directly loaded into a memory and contains software code. After being loaded and executed by a computer, the computer program product can realize the energy efficiency determination method for a refrigeration room provided in the above embodiments.

[0250] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for determining the energy efficiency of a refrigeration room, characterized in that, include: Obtain the energy consumption model of the chiller room and the operating strategy selected by the user; Based on the aforementioned operating strategy, the operating parameters of the chiller room are determined; wherein, the operating parameters include: hourly cooling load, chilled water supply and return temperature difference, chilled water supply temperature, first condensing load, cooling water supply and return temperature difference, and cooling water return temperature; Based on the hourly cooling load, the chilled water supply and return temperature difference, the chilled water supply temperature, the first condensing load, the cooling water supply and return temperature, and the cooling water return temperature, determine the chilled water flow rate, the chilled water return temperature, the second condensing load, the cooling water flow rate, and the cooling water supply temperature. The energy efficiency ratio of the chiller room is calculated based on the second condensing load, the chilled water flow rate, the cooling water flow rate, the cooling water supply and return temperature difference, the cooling water return temperature, and the energy consumption model. The step of determining the second condensing load based on the hourly cooling load, the chilled water supply and return temperature difference, the chilled water supply temperature, the first condensing load, the cooling water supply and return temperature difference, and the cooling water return temperature includes: The chilled water flow rate and the chilled water return temperature are determined based on the hourly cooling load, the chilled water supply and return temperature difference, and the chilled water supply temperature. Based on the chilled water flow rate, the chilled water flow rate of each chiller unit is calculated; The chilled water supply temperature of each chiller unit is calculated based on the chilled water flow rate and the chilled water return temperature of each chiller unit. Based on the cooling water return temperature and the chilled water supply temperature of each chiller unit, the third condensing load is calculated iteratively using the energy consumption model. When the relative error between the third condensing load and the first condensing load is less than a preset threshold, the third condensing load is determined as the second condensing load.

2. The method according to claim 1, characterized in that, The energy consumption model of the refrigeration room includes the energy consumption model of the chiller unit, the energy consumption model of the chilled water pump, the energy consumption model of the cooling water pump, and the energy consumption model of the cooling tower.

3. The method according to claim 2, characterized in that, The chilled water supply temperature of each of the aforementioned chiller units satisfies the following relationship: in, The chilled water supply temperature for each of the chiller units; The chilled water return temperature; The cooling load rate of each chiller unit; The chilled water flow rate for each chiller unit; =1, 2, ..., n, where n is a positive integer.

4. The method according to claim 1, characterized in that, The chilled water flow rate satisfies the following relationship: in, The chilled water flow rate; The hourly cooling load; This is the specific heat capacity of water; The temperature difference between the supply and return water for the chilled water.

5. The method according to claim 2, characterized in that, The calculation of the energy efficiency ratio of the chiller room based on the first condensing load, the chilled water flow rate, the cooling water flow rate, the cooling water supply and return temperature difference, the cooling water return temperature, the cooling water flow rate, and the energy consumption model includes: The energy consumption of the chiller unit is calculated based on the second condensation load. The chilled water flow rate is input into the energy consumption model of the chilled water pump, and the energy consumption of the chilled water pump is output. The cooling water flow rate is input into the energy consumption model of the cooling water pump, and the energy consumption of the cooling water pump is output. The supply and return water temperature difference and the return water temperature are input into the energy consumption model of the cooling tower, and the energy consumption of the cooling tower is output. The energy efficiency ratio of the chiller room is calculated based on the energy consumption of the chiller unit, the chilled water pump, the cooling water pump, and the cooling tower.

6. The method according to claim 1, characterized in that, The operational strategy includes: The operating strategy for the number of chillers, chilled water pumps, cooling water pumps and cooling towers; the cooling load rate allocation strategy for the chillers; the frequency control strategy for the chilled water pumps and the cooling water pumps; and the setting strategy for the chilled water supply temperature, the chilled water supply and return temperature difference, the cooling water return temperature and the cooling water supply and return temperature difference. The frequency control strategy includes a variable frequency control strategy and a fixed frequency control strategy, and the setting strategy includes a fixed temperature control strategy and a variable temperature control strategy.

7. The method according to claim 1, characterized in that, The hourly cooling load is the hourly cooling load for the entire year of 8760 hours, obtained from simulation calculations of the target building.

8. The method according to any one of claims 1 to 2 or 4 to 7, characterized in that, The method further includes: The operating data of the chiller room is collected; wherein, the operating data includes outdoor wet-bulb temperature, evaporator evaporation temperature, chilled water supply temperature, chilled water return temperature, chilled water flow rate, condenser condensation temperature, cooling water supply temperature, cooling water return temperature, cooling water flow rate, chiller unit cooling load, energy efficiency ratio, chilled water supply temperature, chilled water pump operating power and cooling water flow rate, cooling water pump operating power and chilled water flow rate, cooling tower outlet temperature, inlet temperature and operating power; Based on the operating data and the least squares method, an energy consumption model is established for the chiller unit, the chilled water pump, the cooling water pump, and the cooling tower.

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