An air energy carrying system and a dynamic control method thereof

Abstract

The present invention discloses an air energy carrier system and a dynamic control method thereof. It includes an air conditioning system arranged in a personnel use area, the air conditioning system includes an air outlet, a return air outlet, a heat exchange surface, an air volume control unit, a temperature control unit and a convection heat exchange structure, a temperature detection unit is arranged at each air outlet and return air center position, an air volume detection unit and a heat flux density detection unit are arranged at the heat exchange surface, the personnel use area includes an indoor return air outlet, a fresh air outlet, an exhaust outlet and a window, and a fourth temperature detection unit is arranged at the center of the indoor return air outlet. The advantages of the present invention are that by establishing a startup dynamic control based on thermophysical parameters, a rapid hourly prediction of the response time and temperature of the dynamic air energy carrier system is achieved, and the control of the indoor thermal environment and the heat exchange surface temperature effectively follows the dynamic change trend of time, thereby improving the accuracy of the control and facilitating the energy saving and optimization of the air conditioning system.

Description

Technical Field

[0001] The present invention belongs to the technical field of temperature control, and in particular relates to an air energy carrying system and a dynamic control method thereof. Background Art

[0002] A comfortable indoor thermal environment is very important for human body and mind and efficient work. Radiant systems with energy-saving potential can reduce building energy consumption while improving comfort. The dynamic thermal characteristics of radiant systems with air as the heat transfer medium are affected by physical parameters such as the circulating energy storage layer and the characteristics of the heat exchange surface, and have characteristics such as nonlinearity, inertia and hysteresis. For air-carrying energy systems, it is crucial to quickly predict the response time and thermal performance of the startup process of heating and cooling systems to control and optimize the system. For temperature control, traditional PID control cannot perceive future temperature changes in the indoor environment, and has low control accuracy and large control volatility. At present, the prediction and control methods of air-conditioning systems include linear regression, artificial neural networks, support vector machines, CFD transient simulation and other methods. Among them, the linear regression method cannot be applied to the characteristics of nonlinear changes in air-carrying energy systems; methods such as big data machine learning require a large amount of data for training. Different air-carrying energy system solutions require a large amount of different data to ensure the accuracy of the model. This method is greatly affected by missing data; CFD steady-state numerical simulation methods can optimize solutions based on thermal physical characteristics, but the transient CFD method requires large computing resources. There are related literatures that have studied and reported on the solution to the above-mentioned problems existing in the prediction and control technology of the existing air-conditioning system: For example, an air-conditioning control algorithm evaluation method, device, equipment and storage medium with publication number CN115930376A, based on the performance indicators accumulated in the current cycle, obtains the evaluation results of each candidate control algorithm in the current cycle, which can solve the problem of inaccurate evaluation results of the existing air-conditioning control algorithm and improve the accuracy of the evaluation results of the air-conditioning control algorithm. However, this method is affected by the accuracy of the preset model parameters, does not consider the thermophysical characteristics of the air-conditioning system, and lacks the flexibility of optimizing the scheme control. Another example is an air-conditioning startup control method, control device and air-conditioning system with publication number CN110986304A, which can control the air-conditioning to start automatically in advance, so that the indoor environment can be changed before the user arrives home, so that the user can enjoy a comfortable indoor environment temperature when he arrives home, and controls the air-conditioning to enter the automatic operation mode in the preset time period, so that the control of the air-conditioning is more targeted, which is conducive to avoiding the air-conditioning being in standby state all day, and can also play a role in energy saving. However, this method cannot predict the time required to start the air-conditioning in advance to achieve the target ambient temperature, and cannot accurately control after changing the air-conditioning system scheme. And a dynamic air conditioning system energy consumption prediction model construction, prediction method and device with publication number CN112524751A, by establishing an improved particle swarm optimization BP neural network to predict the energy consumption of the dynamic air conditioning system hour by hour, the accuracy of energy consumption prediction is improved, which is beneficial to the energy saving and optimization control of the air conditioning system; by establishing a dynamic energy consumption control model, the indoor thermal environment can effectively follow the dynamic change trend of the outdoor temperature. However, this method requires a lot of initial data to be collected, and the accuracy of the method requires a large amount of data for model training, and the thermal physical characteristics of the air conditioning system are not considered. Summary of the invention

[0003] The purpose of the present invention is to provide an air energy carrier system and a dynamic control method thereof, so as to accurately characterize the nonlinear dynamic startup characteristics of the air energy carrier system while avoiding the shortcomings of the prediction model requiring a large amount of training data and a large amount of computing resources, so as to achieve the purpose of quickly and accurately predicting the changing trends of the indoor environment and the heat exchange surface over time.

[0004] In order to achieve the above-mentioned purpose, one of the technical solutions adopted by the present invention is: an air energy carrying system, including an air conditioning system arranged in a personnel use area, the air conditioning system including an air outlet, a return air outlet, a heat exchange surface, an air volume control unit, a temperature control unit and a convection heat exchange structure, a first temperature detection unit and a first air volume detection unit are arranged at the center of the air outlet, a second temperature detection unit is arranged at the center of the return air outlet, a third temperature detection unit is arranged at the center of the heat exchange surface, and a heat flux density detection unit is arranged near the third temperature detection unit, the personnel use area includes an indoor return air outlet, a fresh air outlet, an exhaust outlet and a window, the fresh air outlet is arranged on the upper side of the room, the exhaust outlet is arranged on the lower side of the room, the fresh air outlet, the exhaust outlet and the indoor return air outlet are arranged on different walls, and a fourth temperature detection unit is arranged at the center of the indoor return air outlet.

[0005] In a feasible implementation, the air energy carrying system also includes a circulating energy storage area, which is an air distribution area from the heat exchange surface to the air blown out after being heated / cooled by the convective heat exchange structure, and is used to store the air heated or cooled by the convective heat exchange structure.

[0006] In a feasible implementation, the height of the circulating energy storage area is 0.15-0.5m.

[0007] In a feasible implementation, the heat exchange surface is a metal porous plate or a lightweight material flat plate, and the size and position of the heat exchange surface is one or more combinations of the indoor top, side wall, bottom, an entire wall / window, and a local area.

[0008] In a feasible implementation, the size and position of the heat exchange surface are the area and position corresponding to the vertical mapping area of ​​the personnel use area.

[0009] In a feasible implementation, the convection heat exchange structure is a fan coil unit or an indoor unit of an air conditioner.

[0010] In a feasible implementation, the air energy carrying system further includes a temperature detection unit disposed at a center position at a human sitting height in the personnel use area.

[0011] In a feasible implementation, there are two return air vents, which are respectively arranged on the upper and lower sides of the room.

[0012] The second technical solution adopted by the present invention is: the dynamic control method of the above-mentioned air energy carrier system includes the following steps: S1, obtaining the physical parameters of the air energy carrier system through each detection unit; S2, calculating the equivalent physical characteristics of the air energy carrier system; S3, collecting initial environmental parameter values; S4, predicting the system startup response time; S5, controlling the system start and stop process according to the change of the indoor average temperature over time, including the time from system startup to the beginning of the change of the heat exchange surface temperature, and the rapid response time from the beginning of the change of the heat exchange surface temperature to the beginning of the change of the indoor temperature. The total response time obtained according to the change of the heat exchange surface temperature and the indoor temperature over time when the heat exchange is in equilibrium is the control time.

[0013] In a feasible implementation, the physical parameters in S1 include the area of ​​the personnel use area, denoted as A, in m 2 ; Measure the center temperature of the indoor return air outlet, recorded as T r , unit ℃; the heat flux density transferred from the radiation surface to the room is denoted as q, unit W / m 2 ; Air supply volume L p , unit is m 3 , the supply air temperature is recorded as T in (℃), return air temperature T in the circulating energy storage area r’ (℃); ρ p is the air density, kg / m3; c p is the specific heat capacity of air, kJ / (kg·℃); heat transfer surface density ρ(kg / m 3 ); Specific heat capacity of heat exchange surface C (kJ / kg·℃); Heat exchange surface thickness H (m); Average temperature of supply and return air T ɑ (℃); Convective radiation heat exchange coefficient h(W / m 2 ·℃).

[0014] In one possible implementation, the equivalent physical properties in S2 include an equivalent thermal resistance, denoted as R L , the energy stored in the circulating energy storage layer, denoted as Q stored , the equivalent air energy heat capacity C, the heat capacity of the heat exchange surface material C1, and the heat capacity of the air energy cycle storage area C2 are calculated as follows:

[0015] ;

[0016] ;

[0017] ;

[0018] ;

[0019] C1 is the heat capacity of the heat transfer surface material, kJ / (m 2·℃); the heat transfer delay time caused by C1 is t1, which is defined as the delay time of the heat transfer surface. C2 is the heat capacity of the air energy storage layer, kJ / (m 2 ·℃). The heat transfer delay time affected by C2 is t2, which is defined as the rapid response time of the heat exchange surface.

[0020] In a feasible implementation, the initial environmental parameters in S3 include the initial temperature T of the heat exchange surface. i (℃), initial indoor temperature T r i (℃).

[0021] In a feasible implementation, the response time τ to reach the target temperature is obtained in S4; the delayed response time t1 of the heat exchange surface; the fast response time t2 of the real-time adjustment; the heat exchange surface reaches the equilibrium temperature T e The total response time t total , the calculation formulas are:

[0022] t1=C1 / (h+1 / R L );

[0023] t2=C2 / (h+1 / R L );

[0024] t total =-ln{1-[(T e -T i ±0.2) / (T e -T i )]} / [(h+1 / R L ) / C2]-C1 / (h+1 / R L );

[0025] In a feasible implementation, the start-stop control in S5 is specifically as follows: obtaining the dynamic change of the heat exchange surface temperature Ts following the time τ, recorded as ; Corresponding to the average indoor temperature T r Following the dynamic changes of time τ, it is recorded as .

[0026] Heat exchange surface temperature T s The prediction formula that changes with system startup time is:

[0027] ;

[0028] Average indoor temperature Heat exchange surface temperature The relationship is defined by the following formulas:

[0029] ;

[0030] ;

[0031] , , b1, b2, c are constants, , They are the parameters when the dynamic startup time is in the stage of t1-t2, b1 and b2 are the parameters when the dynamic startup time is greater than t2.

[0032] In a feasible implementation, when d2=1.1m, c is 0.5, and the ceiling cooling parameters are , , b1 and b2 are 0.0345, 0.938, 2.7351, 0.7968 respectively, and the heating parameters are 0.1815, 0.315, 11.5, 0.691.

[0033] In a feasible implementation, the personnel use area is the effective working area of ​​the air conditioner, the area range is the area from the human ankle (denoted as d1) to the head height (denoted as d3), the area away from the wall (denoted as d4), and the central temperature at the sitting height of the human body (denoted as d2) is defined as the average indoor temperature.

[0034] In a feasible implementation, d1=0.1m, d2=0.8-1.4m, d3=1.8m, d4=0.5m.

[0035] Beneficial effects of the present invention: Based on thermophysical parameters that are easy to measure, the present invention simplifies the startup response process of the system heat exchange surface by defining equivalent thermal characteristic parameters and combining the energy balance method. By quickly predicting the heat exchange surface temperature and system response time, the indoor temperature after the system is started can be started and stopped.

[0036] This dynamic control method does not require a large amount of basic data for model training and prediction. Based on the system's thermophysical parameters, it can predict the startup response time and heat exchange surface temperature of the air energy carrier system, thereby controlling the average indoor temperature. Based on the startup dynamic control of thermophysical parameters, it can quickly predict the response time and temperature of the dynamic air energy carrier system hour by hour, and effectively control the dynamic change trend of the indoor thermal environment and heat exchange surface temperature over time, thereby improving the accuracy of control and facilitating energy saving and optimization of the air conditioning system. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art and the beneficial effects of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other structures can be obtained based on the structures shown in these drawings without paying creative work.

[0038] Figure 1 It is a schematic diagram of the structure of the air energy carrying system of the present invention.

[0039] Figure 2 It is a schematic diagram of the process of the present invention.

[0040] In the figure: 1-air outlet, 2-return air outlet, 3-indoor return air outlet, 4-fan coil, 5-fresh air outlet, 6-exhaust outlet, 7-window, 8-air outlet central temperature sensor, 9-return air outlet central temperature sensor, 10-indoor return air outlet central temperature sensor, 11-temperature sensor, 12-heat exchange surface central temperature sensor, 13-air outlet central flow sensor, 14-heat exchange surface central heat flux density sensor, 15-air volume regulating valve, 16-temperature control regulating valve, 17-circulating energy storage area, 18-heat exchange surface, 19-personnel use area. DETAILED DESCRIPTION

[0041] See also Figure 1-Figure 2In an embodiment of the present application, an air energy carrying system is provided, including an air conditioning system arranged in a personnel use area 19, the air conditioning system includes an air outlet 1, a return air outlet 2, a heat exchange surface 18, an air volume control unit, a temperature control unit and a convection heat exchange structure. The air volume control unit and the temperature control unit of this embodiment are respectively an air volume regulating valve 15 and a temperature control regulating valve 16 on the fan coil unit. A first temperature detection unit and a first air volume detection unit are arranged at the center of the air outlet, a second temperature detection unit is arranged at the center of the return air outlet, a third temperature detection unit is arranged at the center of the heat exchange surface, and a heat flux density detection unit is arranged near the third temperature detection unit. The heat flux density detection unit of this embodiment is a heat flux density sensor 14 at the center of the heat exchange surface. Domain 19 includes indoor return air vents 3, fresh air vents 5, exhaust vents 6 and windows 7. The fresh air vents are arranged on the upper side of the room, and the exhaust vents are arranged on the lower side of the room. The fresh air vents, exhaust vents and indoor return air vents are arranged on different walls. A fourth temperature detection unit is arranged at the center of the indoor return air vent. The first temperature detection unit, the second temperature detection unit, the third temperature detection unit and the fourth temperature detection unit of this embodiment are respectively the outlet center temperature sensor 8, the return air vent center temperature sensor 9, the heat exchange surface center temperature sensor 12 and the indoor return air vent center temperature sensor 10. There are two return air vents 2 in this embodiment, one is arranged at the top of the room and the other is arranged at the lower side of the room. The exhaust vents and the return air vents in the human body use area are arranged at the lower side of the room to make the indoor heat and humidity environment distribution better.

[0042] The air energy carrying system described in this embodiment further includes a circulating energy storage area 17 for storing air heated or cooled by the convection heat exchange structure.

[0043] The height of the circulating energy storage area in this embodiment is 0.15-0.5m.

[0044] The heat exchange surface described in this embodiment adopts a metal porous plate or a lightweight material flat plate. The size and position of the heat exchange surface are one or more combinations of the indoor top, side wall, bottom, a whole wall / window, and a local area. The heat exchange surface can be divided into blocks, combined, and controlled by regions. The heat exchange surface of this embodiment is set at the indoor top to form two circulating energy storage areas; the heat exchange surface of this embodiment is set at the indoor top to form two circulating energy storage areas.

[0045] The size and position of the heat exchange surface in this embodiment are the area and position corresponding to the vertical mapping area of ​​the personnel use area.

[0046] The convection heat exchange structure described in this embodiment is a fan coil unit 4 .

[0047] In this embodiment, a temperature sensor 11 is also provided at the height of the personnel use area d2.

[0048] Working principle of air energy system:

[0049] The air heated or cooled by the fan coil unit is sent to the circulating energy storage area 17, so that the heat exchange surface 18 (metal microporous plate / light material flat plate) is heated / cooled by the air to form a heat exchange surface, and heat is exchanged with the air in the indoor personnel use area 19. When the heat exchange surface is a metal microporous plate, part of the air returns to the fan coil unit from the circulating energy storage layer, and part of the air flows into the indoor personnel use area and then returns to the fan coil unit. When the heat exchange surface is a light material flat plate, all the air enters the circulating energy storage layer, heats / cools the heat exchange surface, and then returns to the fan coil unit. The circulating energy storage area stores the heated / cooled air and has a heat / cold radiation effect on the heat exchange surface 18.

[0050] The second technical solution adopted by the present invention is: the dynamic control method of the above-mentioned air energy carrier system includes the following steps: S1, obtaining the physical parameters of the air energy carrier system through each detection unit; S2, calculating the equivalent physical characteristics of the air energy carrier system; S3, collecting initial environmental parameter values; S4, predicting the system startup response time; S5, controlling the system start and stop process.

[0051] The physical parameters in S1 of this embodiment include the area of ​​the personnel use area, denoted as A, in m 2 ; Measure the center temperature of the indoor return air outlet, recorded as T r , unit ℃; the heat flux density transferred from the radiation surface to the room is denoted as q, unit W / m 2 ; Air supply volume L p , unit is m 3 , the supply air temperature is recorded as T in (℃), return air temperature T in the circulating energy storage area r’ (℃); ρ p is the air density, kg / m3; c p is the specific heat capacity of air, kJ / (kg·℃); heat transfer surface density ρ(kg / m 3 ); Specific heat capacity of heat exchange surface C (kJ / kg·℃); Heat exchange surface thickness H (m); Average temperature of supply and return air T ɑ (℃); Convective radiation heat exchange coefficient h (W / m 2 ·℃).

[0052] In this embodiment, the equivalent physical properties of S2 include equivalent thermal resistance, denoted as R L , the energy stored in the circulating energy storage layer, denoted as Q stored , equivalent air energy heat capacity C, heat capacity of heat exchange surface material C1, heat capacity of air energy cycle storage area C2, the calculation formulas are:

[0053] ;

[0054] ;

[0055] ;

[0056] ;

[0057] C1 is the heat capacity of the heat transfer surface material, kJ / (m 2 ·℃); the heat transfer delay time caused by C1 is t1, which is defined as the delay time of the heat transfer surface. C2 is the heat capacity of the air energy storage layer, kJ / (m 2 ·℃). The heat transfer delay time affected by C2 is t2, which is defined as the rapid response time of the heat exchange surface.

[0058] In this embodiment, the initial environmental parameters in S3 include the initial temperature T of the heat exchange surface. i (℃), initial indoor temperature T i r (℃).

[0059] In this embodiment, S4 obtains the response time τ to reach the target temperature; the delayed response time t1 of the heat exchange surface; the fast response time t2 adjusted in real time; the heat exchange surface reaches the equilibrium temperature T e The total response time t total , the calculation formulas are:

[0060] t1=C1 / (h+1 / R L );

[0061] t2=C2 / (h+1 / R L );

[0062] t total =-ln{1-[(T e -T i ±0.2) / (T e -T i )]} / [(h+1 / R L ) / C2]-C1 / (h+1 / R L );

[0063] The start-stop control in S5 of this embodiment is specifically as follows: obtaining the dynamic change of the heat exchange surface temperature Ts following the time τ, which is recorded as ; Corresponding to the average indoor temperature T r Following the dynamic changes of time τ, it is recorded as .

[0064] Heat exchange surface temperature T s The prediction formula that changes with system startup time is:

[0065] ;

[0066] Average indoor temperature Heat exchange surface temperature The relationship is defined by the following formulas:

[0067] ;

[0068] ;

[0069] , b, c are constants, , They are the parameters when the dynamic startup time is in the stage of t1-t2, b1 and b2 are the parameters when the dynamic startup time is greater than t2.

[0070] In this embodiment, c is 0.5, and the ceiling cooling parameter , , b1 and b2 are 0.0345, 0.938, 2.7351, 0.7968 respectively, and the heating parameters are 0.1815, 0.315, 11.5, 0.6919. The calculation results of the formula are obtained by fitting regression and will vary due to differences in the physical structure of the system.

[0071] In this embodiment, the personnel use area is the effective working area of ​​the air conditioner, and the area range is the area from the human ankle recorded as d1 to the head height recorded as d3, and the distance from the wall recorded as d4. The central temperature at the sitting height of the human body (recorded as d2) is defined as the indoor average temperature.

[0072] In this embodiment, d1=0.1m, d2=1.1m, d3=1.8m, and d4=0.5m.

[0073] Studies have shown that the physical parameters that affect the system include the air outlet and return air temperatures of the air energy carrier system, the air volume of the circulating energy storage layer, the area, material, thickness, specific heat capacity, density and convection radiation heat transfer coefficient of the radiation heat exchange surface. In addition to the physical characteristic parameters of the system, the initial ambient temperature also affects the final average indoor temperature. The present invention obtains the heat exchange surface parameters: the total area A (m2) is obtained according to the total length and width of the heat exchange surface; the heat exchange surface thickness H (m); the heat exchange surface density ρ (kg / m 3 ), heat transfer surface specific heat capacity C (kJ / kg·℃), convection radiation heat transfer coefficient h (W / m 2 ·℃); Sensors are arranged at the center of the heat exchange surface: The heat flux density sensor at the center of the heat exchange surface can obtain the heat flux density q (W / m 2 ), the heat exchange surface center temperature sensor can obtain the initial temperature T of the heat exchange surface i (℃), heat transfer surface temperature T when heat transfer is balanced e(℃).

[0074] Arrange temperature sensors at the center of each air outlet: The temperature sensor at the center of the air outlet can obtain the air outlet temperature T in (℃), the return air outlet center temperature sensor can obtain the return air outlet temperature T of the circulating energy storage layer r’ (℃), the indoor return air outlet center temperature sensor can obtain the indoor return air outlet temperature T r (℃), the outlet center flow sensor can obtain the air supply volume L p (m 3 ).

[0075] Sensors are arranged in the personnel-used area: The temperature sensor at height d2 in the personnel-used area can obtain the indoor initial temperature T i r (℃), average indoor temperature T when heat exchange is balanced r (t total )(℃).

[0076] Based on the above physical parameters, the start-up response time and heat exchange surface temperature of the air energy system are predicted, so as to control the indoor average temperature. The control method is written into the controller in C language, and the sensor signal is transmitted to the controller in real time through the controller area network (CAN) bus. The controller is connected to the controller to control the air volume and air temperature of the air outlet, the opening of the air volume regulating valve, the cooling capacity of the air conditioning system, the temperature control regulating valve of the heating supply, the start and stop of the fan coil, and the start and stop of the air conditioning system. The signals sent by the outlet center temperature sensor, the return air outlet center temperature sensor, the indoor return air outlet center temperature sensor, the personnel use area d2 height temperature sensor, the heat exchange surface center temperature sensor, the outlet center flow sensor, and the heat exchange surface center heat flux density sensor are received. The control algorithm makes a start and stop judgment based on the real-time signal, and sends the action to the air energy air conditioning system through the CAN bus. The air conditioning controls the wind speed / temperature and start and stop control according to the received real-time signal.

[0077] The following is an example of ceiling radiant cooling in summer in an air energy-carrying system in an office in Changsha. The office area is 15.5m 2 ; Heat exchange surface temperature (after stabilization) T s =21.8℃; Indoor return air temperature T r =24.7℃; heat flux from the radiation surface to the room q=29.7 W / m 2 ; Air density ρ p =1.005kg / m 3 , specific heat capacity c p =1.184kJ / (kg·℃), air volume L p =128m 3, supply air temperature T in =12.7℃, the return air temperature of the circulating energy storage layer Tr-ACERZ=19℃, the heat exchange surface density of the metal aluminum plate ρ=2610kg / m 3 ; Specific heat capacity of the metal aluminum plate heat exchange surface c = 0.9kJ / (kg·℃); Thickness of the metal aluminum plate heat exchange surface H = 0.001m; Average temperature of the return air T a =18.7℃; convection radiation heat exchange coefficient h=4.6W / m 2 ℃; initial temperature of heat exchange surface in summer T i =28.8℃; initial average indoor temperature T i r =28.9℃.

[0078] According to the above formula, the heat transfer delay time is calculated as follows: t1=1.17 / (4.6+1 / 0.097)=1.3(min)

[0079] According to the above formula, the fast response time is calculated as follows: t2=20 / (4.6+1 / 0.097)=22(min)

[0080] The total response time is calculated according to the above formula: t total =-ln{1-[(21.8-28.8+0.2) / (21.8-28.8)]} / [(4.6+1 / 0.097) / 20]-1.17 / (4.6+1 / 0.097)=78 (min)

[0081] According to the above formula, the change of heat exchange surface temperature over time is calculated: (τ>t1)T s (τ) =(21.8-28.8)×{1-exp[-(τ-1.3*60 / 1000)·(4.6+1 / 0.097) / 20]}+28.8=-7×{1-exp[-0.75×(τ-0.078)]}+28.8

[0082] The heat exchange surface temperature when the heat exchange equilibrium is calculated is: T e =(4.6×28.8+18.7 / 0.097) / (4.6+1 / 0.097)=21.8℃

[0083] According to the above formula, the indoor temperature when heat exchange is balanced is calculated:

[0084] T r (ttotal)=(-7×{1-exp[-0.75×(78×60 / 1000-0.078)]}+28.8-2.7351) / 0.7968=24℃

[0085] According to the above formula, the indoor temperature change over time is calculated as follows: (τ>t1)

[0086] T r (τ)=(24-28.9)×{1-exp[-(τ-1.3×60 / 1000)×0.5×(4.6+1 / 0.097) / 20]}+28.8=-4.9×{1-exp[-0.375×(τ-0.078)]}+28.9

[0087] It can be seen that the control characteristics of the air-carrying ceiling cooling system are:

[0088] The time from system startup to the start of the heat exchange surface temperature change, that is, the heat transfer delay t1 between the system and the heat exchange surface, is about 2 minutes. The fast response time t2 from the start of the heat exchange surface temperature change to the start of linear, stable, and rapid changes in the indoor temperature is 22 minutes, that is, the delay time between the system and the heat exchange surface fast response is about 0.38 h. The total response time for the heat exchange surface temperature to drop by 7°C (initial temperature 28°C - equilibrium temperature 21°C) is about 1.3 h, corresponding to a decrease in indoor temperature of about 4°C (initial temperature 28°C - equilibrium temperature 24°C).

[0089] This means that in summer, the system must be started at least 1.3 hours before the working time to ensure that the ceiling surface temperature is in a balanced state. If the system needs to be adjusted quickly in real time, it should be done at least 0.36 hours in advance. The calculation of the present invention can achieve the expected control effect within the target time.

[0090] In the application scenarios of the present invention, both the circulating energy storage area and the personnel use area can perform air cooling / heating cycles, which are used in common civil building scenarios; or only the circulating energy storage area can perform air cooling / heating cycles, and the wind in the personnel use area is directly discharged, which is used in scenarios such as operating rooms and clean rooms with higher indoor air quality.

[0091] The present invention performs fast dynamic control on the temperature of the air energy radiation heat exchange surface, the system startup response time, and the average indoor temperature. The method establishes a startup dynamic control based on thermophysical parameters to achieve fast hourly prediction of the response time and temperature of the dynamic air energy system, and effectively controls the indoor thermal environment and the heat exchange surface temperature to follow the dynamic change trend of time, thereby improving the accuracy of control and facilitating energy saving and optimization of the air conditioning system.

[0092] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A dynamic control method for an air energy carrying system, the air energy carrying system comprising an air conditioning system arranged in a personnel use area, the air conditioning system comprising an air outlet, a return air outlet, a heat exchange surface, an air volume control unit, a temperature control unit and a convection heat exchange structure, a first temperature detection unit and a first air volume detection unit are arranged at the center of the air outlet, a second temperature detection unit is arranged at the center of the return air outlet, a third temperature detection unit is arranged at the center of the heat exchange surface, a heat flux density detection unit is arranged near the third temperature detection unit, the personnel use area comprises an indoor return air outlet, a fresh air outlet, an exhaust outlet and a window, the fresh air outlet is arranged at the upper side of the room, the exhaust outlet is arranged at the lower side of the room, the fresh air outlet, the exhaust outlet and the indoor return air outlet are arranged on different walls, a fourth temperature detection unit is arranged at the center of the indoor return air outlet, characterized in that The dynamic control method includes the following steps: S1, the physical parameters of the air energy system are obtained through each detection unit. The physical parameters in S1 include the area of ​​the personnel use area, denoted as A, in m 2 ; Measure the center temperature of the indoor return air outlet, recorded as T r , unit ℃; the heat flux density transferred from the radiation surface to the room is denoted as q, unit W / m 2 ; Air supply volume L p , unit is m 3 , the supply air temperature is recorded as T in , the return air temperature T of the circulating energy storage area r’ ρ p is the air density; c p is the specific heat capacity of air, kJ / (kg·℃); heat transfer surface density ρ, unit kg / m 3 ; Specific heat capacity of heat exchange surface C, kJ / (kg·℃); Heat exchange surface thickness H, unit m; Average temperature of supply and return air T ɑ , unit ℃; convection radiation heat exchange coefficient h, unit W / m 2 ℃; S2, calculate the equivalent physical properties of the air energy system, including the equivalent thermal resistance, denoted as R L , the energy stored in the circulating energy storage layer, denoted as Q stored , equivalent air energy heat capacity C, heat capacity of heat exchange surface material C1, heat capacity of air energy cycle storage area C2, R L , Q stored The calculation formulas for C1 and C2 are: ； ； ； ； Among them, T s is the average temperature of the heat transfer surface, C1 is the heat capacity of the heat transfer surface material; the heat transfer delay time caused by C1 is t1, which is defined as the delay time of the heat transfer surface; C2 is the heat capacity of the air energy storage layer, and the heat transfer delay time affected by C2 is t2, which is defined as the rapid response time of the heat transfer surface; S3, collect the initial environmental parameter values, including the initial temperature T of the heat exchange surface i , initial indoor temperature T i r ; S4, predict the system startup response time. The response time is the time τ required for the heat exchange surface or the room to reach the target temperature after the system is started. The time from system startup to the start of the heat exchange surface temperature change is the heat exchange surface delayed response time t1. The time from the start of the heat exchange surface temperature change to the start of the indoor temperature linear change with the heat exchange surface is the fast response time t2. The time from system startup to the heat exchange surface reaching the equilibrium temperature T e The total response time t total , t1, t2, t total The calculation formulas are: t1=C1 / (h+1 / R L ); t2=C2 / (h+1 / R L ); t total =-ln{1-[(T e -T i ±0.2) / (T e -T i )]} / [(h+1 / R L ) / C2]-C1 / (h+1 / R L ); S5, control the system start-stop process according to the change of the indoor average temperature over time. The start-stop control is specifically as follows: obtain the dynamic change of the average temperature Ts of the heat exchange surface following the time τ, recorded as ; Corresponding to the average indoor temperature T r Following the dynamic changes of time τ, it is recorded as ; T s The prediction formula that changes with system startup time is: ； Average indoor temperature Heat exchange surface temperature The relationship is defined by the following formulas: ； ； , are the parameters of the dynamic start-up time in the stage of t1-t2, b1 and b2 are the parameters of the dynamic start-up time in the stage greater than t2, and c is a constant.

2. The dynamic control method of the air energy carrier system according to claim 1, characterized in that: The indoor average temperature adopts the temperature of different indoor heights or floors.

3. The dynamic control method of the air energy carrier system according to claim 1, characterized in that: The air energy carrying system also includes a circulating energy storage area for storing air heated or cooled by the convection heat exchange structure.

4. The dynamic control method of the air energy carrier system according to claim 1, characterized in that: The height of the circulating energy storage area is 0.15-0.5m.

5. The dynamic control method of the air energy carrier system according to claim 1, characterized in that: The heat exchange surface is a metal porous plate or a light material flat plate, and the size and position of the heat exchange surface is one or more combinations of the indoor top, side wall, bottom, a whole wall / window, and a local area.

6. The dynamic control method of the air energy carrier system according to claim 1, characterized in that: The size and position of the heat exchange surface are the area and position corresponding to the area vertically mapped to the personnel use area.

7. The dynamic control method of the air energy carrier system according to claim 1, characterized in that: The convection heat exchange structure is a fan coil unit or an air conditioner indoor unit.

8. The dynamic control method of the air energy carrier system according to claim 1, characterized in that: It also includes a temperature detection unit arranged at the center of the human body sitting height in the personnel use area; there are two return air vents, which are respectively arranged on the upper and lower sides of the room.

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