CN106202719A - A kind of method setting up indoor thermal environment load model - Google Patents

Abstract

The present invention relates to a kind of method setting up indoor thermal environment load model, influencing each other in conjunction with indoor and outdoor surroundings, being analyzed indoor thermal environment, according to heat balance principle, row write the differential equation between relevant control amount and controlled volume, the differential equation is solved, obtain the Controlling model of thermal environment, finally model has been verified, utilize pid that system is controlled, obtain preferable effect, verify reliability and the reasonability of model.

Description

A kind of method setting up indoor thermal environment load model

Technical field

The invention belongs to environment controlling technique field, particularly to a kind of method setting up indoor thermal environment load model.

Background technology

The place that indoor are human lives, live, work.Showing according to ASSOCIATE STATISTICS, people exist at indoor life-time The people of more than 85% is in the great majority, and more has a lot of modern job worker, and they have exceeded 90% in the indoor time.Indoor Environment substantial connection health and the work efficiency etc. of human body.For reaching blander thermal environment, by air conditioning system to room Interior thermal environment regulates and controls.By the conservative control to air conditioning system, it is provided that to one comfortable indoor thermal environment of people.Want Want air conditioning system is reasonably controlled, need to obtain the model of air conditioning system end and room temperature.

Set up relatively reasonable indoor thermal environment load model, it is possible to achieve the control to indoor thermal environment.At present, have relatively Many methods have been applied to indoor thermal environment modeling.Such as modeling method based on data analysis, it is simply that according to the input of system and Output data analyze the relation of variable each with identification system.Also have multiple regional net models, regional model etc..Based on these sides The model of the indoor thermal environment that method is set up, it is impossible to describe out by most for system dynamic characteristic, in addition it is also necessary to identification out Model constantly check and revise.

Summary of the invention

The shortcoming such as what the model in order to overcome above-mentioned prior art to set up need to constantly be checked and revise, the present invention's Purpose is to provide a kind of method setting up indoor thermal environment load model, can the dynamic characteristic of descriptive system effectively, from And provide foundation to the accurately control of air conditioning system.

To achieve these goals, the technical solution used in the present invention is:

A kind of method setting up indoor thermal environment load model, including:

Step 1: analyze the influence factor of controlled Indoor Thermal Environment, determines the controlled quentity controlled variable of room thermal environment and controlled Amount, arranges according to heat balance principle and preservation of energy and writes the differential equation；

Step 2: analyze physical attribute and its main processing performance of air conditioning system surface cooler, to Qi Shui side and wind side, Arrange according to heat balance principle and preservation of energy and write the differential equation；

Step 3: the differential equation write according to row carries out Laplace transformation, processes the Controlling model obtaining indoor thermal environment.

Compared with prior art, the invention has the beneficial effects as follows:

By solving obtained load model, it is only necessary to know its concrete parameter, it is possible to obtain room Indoor Thermal The Controlling model of environment.Save the time of model of setting up, preferable effect can be obtained again, can descriptive system significantly Dynamic property, can relatively accurately for system control good foundation is provided.

Accompanying drawing explanation

Fig. 1 is the schematic diagram in the controlled room of air-conditioning.

Fig. 2 is the structural representation of surface cooler.

Fig. 3 is the emulation schematic diagram of Controlling model.

Fig. 4 is the analogous diagram of room temperature.

Fig. 5 is the control block diagram of institute's established model.

Fig. 6 is the control analogous diagram of room temperature.

Detailed description of the invention

Embodiments of the present invention are described in detail below in conjunction with the accompanying drawings with embodiment.

A kind of method setting up indoor thermal environment load model of the present invention, the first thermal environment to controlled room are carried out point Analysis, determines controlled quentity controlled variable and the controlled volume of room thermal environment, arranges according to heat balance principle and preservation of energy and writes the differential equation；Then, Analyze the physical characteristic of air conditioning system surface cooler, Qi Shui side and wind side are write micro-according to heat balance principle and law of conservation of energy row Divide equation；Finally, the differential equation writing row carries out Laplace transformation, solves the Controlling model of controlled room and surface cooler respectively. The structure in the controlled room of air-conditioning is as shown in Figure 1.

The present invention specifically includes following steps:

(1) thermal environment in room controlled to air-conditioning is analyzed, and show that the amount of stored heat change of its indoor thermal environment mainly has Following four aspect causes: the most each time period enters into the air heat content of indoor；The most each time period indoor and outdoors leads to Cross the heat output that body of wall is carried out；The most each time period indoor equipment and the heat dissipation capacity of human body；4. the change of indoor wall temperature.Root Can obtain according to heat balance principle and preservation of energy:Wherein, C_z Thermal capacitance for air-conditioning regulation and control room, it is simply that the specific heat capacity of air is multiplied by the volume in room, T_zFor the temperature in room, Q_aFor by sky Adjusting system is supplied to the energy in room, Q_w1For the energy needed for the change of east-west direction body of wall own temperature with by these body of wall indoor The energy sum of outer heat exchange, Q_RFor the energy needed for the change of roof own temperature with by the heat of this body of wall indoor and outdoor The energy sum of exchange, Q_w2For the energy of North and South direction body of wall own temperature change and exchanged by the heat of this body of wall indoor and outdoor Energy sum, Q_rThe energy to indoor offer for indoor equipment and personnel.The variations in temperature of body of wall is had by heat balance principle:

East-west direction wall:Wherein, C_w11 DEG C is raised for east-west direction wall temperature The required energy absorbed, Q_w1zThe energy transmitted to east-west direction wall for indoor, Q_w1oTransmit to east-west direction wall for outdoor Energy, T_w1Temperature for east-west direction wall；North and South direction wall:Wherein, C_w2For south The north raises the energy absorbed required for 1 DEG C, Q to wall temperature_w2zThe energy transmitted to east-west direction wall for indoor, Q_w2oFor outdoor To the energy of east-west direction wall transmission, T_w2Temperature for east-west direction wall；Roof:Wherein, C_RThe energy absorbed required for raising 1 DEG C for roof temperature, Q_RzThe energy transmitted to roof for indoor, Q_RoPass to roof for outdoor The energy passed, T_RTemperature for roof.

According to the data analysis of investigation, the size (quality) of thing wall and north and south wall is different, so their liter high-temperature The energy absorbed just differs, and respectively its row is write equation so above-mentioned.

(2) the water side of analytical table cooler and air side, the structural representation of surface cooler as shown in Figure 2:

Surface cooler is entered by the controllable valve at top, after heating (cooling), from bottom after new wind and return air mixing Flow out.The flow velocity that hot water (cold water) is controlled by controllable valve flows into surface cooler by pipeline, and in surface cooler around with Just air therefrom obtains heat (cold).The temperature of the water in pipeline is changing always, because air can therefrom draw (release) Heat, the temperature of air is changing the most always.Because air is proportional to air and water each temperature to the actual heat flow of water Difference, so being analyzed the available model about this process by above.It is assumed that the variations in temperature of surface cooler self and confession pathogenic wind-warm Degree change is identical, then model of air cooling coil is represented by:Wherein, C_ahFor surface cooler Temperature raises 1 DEG C of required energy, Q_wFor being supplied to the energy of surface cooler, Q for backwater_lossEnergy for surface cooler self loss Amount, Q_aThe energy taken away inside surface cooler for new wind, namely the energy in room, T it is supplied to by air conditioning system_sFor air feed Temperature.By solving this differential equation, it is possible to achieve controlled the purpose of ventilation temperature by the size controlling discharge.

(3) the solving of the differential equation, is analyzed variable therein, utilizes Laplace transform, its time domain converted In complex frequency domain, state the main dynamic characteristic of this system.Solving the main contents obtained is exactly, can be by controlling air-conditioning The flow of system surface cooler water inlet or the temperature of water inlet, change the ventilation temperature of air-conditioned room, by ventilation temperature Change, makes the temperature in room reach setting value.Room temperature and ventilation temperature, each can be obtained by room model is solved The accumulation of heat of direction body of wall and the relation of the transmission of all directions body of wall energy, the change of outdoor temperature, and can as disturbance variable With the change according to indoor and outdoor surroundings temperature, the inlet temperature in room is determined by model of air cooling coil, and model of air cooling coil solves as follows The model of air cooling coil flow that mainly just statement is intake by control air-conditioning, the inlet temperature in control room that can be concrete.Pass through Such process, controls the temperature in room, it is possible to reach preferable effect, because such method for establishing model, permissible Most of dynamic characteristic of sign system itself.The model simultaneous that will be set up, available concrete variable water volume airconditioning control room Between the model of temperature, as follows: Wherein, G₁Initial temperature and the relation of room temperature, G for room₂For The initial temperature of east-west direction wall and the relation of room temperature, G₃Initial temperature and the pass of room temperature for North and South direction wall System, G₄Initial temperature and the relation of room temperature, G for roof₅Change in flow and the relation of room temperature, G for water₆For room Outer variations in temperature and the relation of room temperature, G₇For the relation of supply and return water temperature change with room temperature, T_z(0) it is at the beginning of room Beginning temperature, T_w1(0) it is the initial temperature of east-west direction wall, T_w2(0) it is the initial temperature of North and South direction wall, T_R(0) it is roof Initial temperature,For the flow velocity of air-conditioner water system water,For outdoor dry-bulb temperature,Difference for supply and return water temperature Value (supply water temperature return water temperature).

(4) according to the load model of the indoor thermal environment set up, use the flow velocity of the water of control table cooler, ensure room Temperature be maintained at setting value.The major advantage setting up this system is exactly comprehensively to analyze the thermal environment of air-conditioning equipment and room, logical Cross the control to air conditioning system, finally obtain the target wanted.Using the flow velocity of water in surface cooler in air conditioning system as controlled volume, Other influence factor is satisfied with setting value as objects interfered, the thermal environment being finally reached room.

One specific embodiment of the present invention, it is known that the relevant parameters such as the material of building, structure, the most former according to calorifics Reason, obtains the thermal capacitance of house air, and the thermal capacitance of body of wall, by the above-mentioned transmission function solved, it is possible to obtain the hot ring in room The Controlling model in border, by controlling the flow velocity of chilled water in air conditioning system, the temperature in regulation room.

In order to describe the problem, with a certain R&D units as object, room specifically can be arranged and writes equation below:

$\begin{array}{c}{C}_z\frac{{\mathrm{dT}}_z\left(t\right)}{dt}=f_{sa}{\mathrm{\ρ}}_a{C}_{pa}\left(T_s\right(t)-T_z(t\left)\right)+2U_{w1}{A}_{w1}\left(T_{w1}\right(t)-T_z(t\left)\right)+\\ U_R{A}_R\left(T_R\right(t)-T_z(t\left)\right)+2U_{w2}{A}_{w2}\left(T_{w2}\right(t)-T_z(t\left)\right)+Q_r\left(t\right)\end{array}---\left(1\right)$

$C_{w1}\frac{{\mathrm{dT}}_{w1}\left(t\right)}{dt}=U_{w1}{A}_{w1}\left(T_z\right(t)-T_{w1}(t\left)\right)+U_{w1}{A}_{w1}\left(T_o\right(t)-T_{w1}(t\left)\right)---\left(2\right)$

$C_{w2}\frac{{\mathrm{dT}}_{w2}\left(t\right)}{dt}=U_{w2}{A}_{w2}\left(T_z\right(t)-T_{w2}(t\left)\right)+U_{w2}{A}_{w2}\left(T_o\right(t)-T_{w2}(t\left)\right)---\left(3\right)$

$C_R\frac{{\mathrm{dT}}_R\left(t\right)}{dt}=U_R{A}_R\left(T_z\right(t)-T_R(t\left)\right)+U_R{A}_R\left(T_o\right(t)-T_R(t\left)\right)---\left(4\right)$

$\begin{array}{c}{C}_{ah}\frac{{\mathrm{dT}}_s\left(t\right)}{dt}=f_{sw}\left(t\right){\mathrm{\ρ}}_w{C}_{pw}\left(T_{wi}\right(t)-T_{wo}(t\left)\right)+{\left(UA\right)}_{ah}\left(T_o\right(t)-T_s(t\left)\right)+\\ f_{sa}{\mathrm{\ρ}}_a{C}_{pa}\left(T_m\right(t)-T_s(t\left)\right)\end{array}---\left(5\right)$

$T_m\left(t\right)=\frac{f_{ra}{\mathrm{\ρ}}_a{T}_z\left(t\right)+f_{oa}{\mathrm{\ρ}}_a{T}_o\left(t\right)}{{\mathrm{\ρ}}_a{f}_{ra}+{\mathrm{\ρ}}_a{f}_{oa}}---\left(6\right)$

Wherein, f_saFor the volume flow rate of air feed, ρ_aFor the density of air, C_paFor the specific heat capacity of air, T_sTemperature for air feed Degree, U_w1For the heat transfer coefficient of east-west direction wall, A_w1For the area of east-west direction wall, U_RFor the heat transfer coefficient on roof, A_RFor roof Area, T_RFor the temperature on roof, U_w2For the heat transfer coefficient of North and South direction wall, A_w2For the area of North and South direction wall, T_w2For north and south The temperature of wall, T_oFor outdoor temperature, f_swFor supply water volume flow rate, for the controlled quentity controlled variable of this model, ρ_wFor the density of water, C_pwFor Specific heat of water holds, T_wiFor the temperature supplied water, T_woFor the temperature of backwater, (UA)_ahHeat transfer coefficient for air-treatment machine set system (infiltration coefficient), T_mAfter mixing for new wind and return air, the temperature of mixed wind, f_raFor the volume flow rate of return air, f_oaVolume for new wind Flow velocity.

After above formula is carried out linearization process to them, then become algebraic equation, algebraic equation through Laplace transform In the ratio of output and input quantity transmit function exactly.Solve and can obtain:

$\begin{array}{c}{T}_z\left(s\right)=G_z\left(s\right)\{{\mathrm{\βG}}_a\left(s\right)\[\mathrm{\θ}{\tilde{f}}_{sw}\left(s\right)+\mathrm{\μ}{\tilde{T}}_o\left(s\right)+\mathrm{\β}{\tilde{T}}_m\left(s\right)+C_{ah}{T}_s\left(0\right)\]\\ +C_z{T}_z\left(0\right)+G_{w1}\left(s\right)\[\mathrm{\γ}\left(T_z\right(s)+T_o(s\left)\right)+C_{w1}{T}_{w1}\left(0\right)\]\\ +C_{w2}\left(s\right)\[\mathrm{\δ}\left(T_z\right(s)+T_o(s\left)\right)+C_{w2}{T}_{w2}\left(0\right)\]\\ +{\mathrm{\λG}}_R\left(s\right)\[\mathrm{\λ}\left(T_z\right(s)+T_o(s\left)\right)+C_R{T}_R\left(0\right)\]\}\end{array}$

Wherein,θ=ρ_wC_pw(T_wi- T_wo), μ=(UA)_ah, β=f_saρ_aC_pa, γ=2U_w1A_w1, δ=2U_w2A_w2, λ=2U_RA_R,

This R&D units room-sized length and width and height are respectively 20 meters, 16 meters and 4 meters.The enclosed structure in house uses Brick wall structure, structure from inside to outside respectively, white lime bisque thickness 5mm, cement mortar thickness 10mm, brick wall thickness 400mm, cement bonded sand The thick 10mm of slurry, nogging thickness 5mm of outside.What this example was set up is the heating situation in room in winter.Determine the hot ring in main room Border model parameter is as follows, C_z=1674.7kj/ DEG C, C_ah=9.04kj/ DEG C, C_pa=1.005kj/kg DEG C, C_pw= 4.187kj/kg DEG C, C_w1=497.8kj/ DEG C, C_w2=400kj/ DEG C, C_R=3200kj/ DEG C, T_z(0)=T_w1(0)=T_w2(0)= T_R(0)=0, (UA)_ah=0.15, f_sa=0.68m³/ s, substitute into the Controlling model obtaining room.

To the checking of model as shown in Figure 3: by the model set up is carried out matlab emulation, main in simulink Build the room thermal environment load model major part set up, carry out verifying the accuracy of model.

Emulation is verified for system, and open loop (uncontrolled) system's transient response to thermal environment model is studied. By the indoor and outdoor temperature of Xi'an University of Architecture and Technology's R&D units on the eight in 20 November year First Five-Year Plan is carried out data acquisition Collection, from the beginning of morning 6, gathers once, one day persistent period for every 30 minutes.The outdoor dry-bulb temperature data input that will gather In the model set up, obtain the temperature of model output.The result of emulation as shown in Figure 4, can describe the model of foundation in figure Dynamic property is similar with the dynamic property of true environment, concrete analysis indoor actual temperature and model output temperature, carries out error Analyze, find that error, between ± 2 DEG C, can meet us and air-conditioning proposes the requirement of certain control strategy, make the heat of indoor Environment reaches the temperature set.It addition, model output temperature is consistent with the actual basic configuration measuring temperature, illustrate to set up Model can react actual indoor thermal environment, the model set up thus has certain practicality.The mathematics set up is described Model can be that the control of indoor thermal environment provides foundation.

The control block diagram of institute's established model, as it is shown in figure 5, major control is the water inlet flow velocity of air conditioning system, is flowed by control Speed, controls the temperature of thermal environment in room.

The flow velocity of water in air conditioning system surface cooler is carried out pid control, controls parameter and utilize particle cluster algorithm, find more excellent Pid control parameter, the pid parameter that this model is chosen is: P_k=1.275, p_i=0.368, p_d=0.786, and emulate, Control result as shown in Figure 6:

From the response diagram obtained after controlling, obtain preferable control effect.During the rising of indoor thermal environment system Between for 2080s (reaching the time near setting value point first), good rapidity has been described；The time to peak of system is The 2740s time of maximum overshoot point (system reach), peak value is 21.7243 DEG C, the overshoot 8.62% of system；The regulation of system Time is 3920s (system transients die-away time), and explanation system has preferable stability；By the observation to control analogous diagram, Can obtain system and reach steady statue at about 4000s, the now output of system and the error of setting value only have 0.4 DEG C, base Originally control target has been reached.In sum, it is more accurate that model is set up, and can state the dynamic characteristic of room model, permissible Pid for indoor thermal environment controls to provide foundation.

Claims (6)

1. the method setting up indoor thermal environment load model, it is characterised in that comprise the following steps:

Step 1: analyze the influence factor of controlled Indoor Thermal Environment, determines controlled quentity controlled variable and the controlled volume of room thermal environment, root Arrange according to heat balance principle and preservation of energy and write the differential equation；

Step 2: analyze the physical attribute of air conditioning system surface cooler and its main processing performance, to Qi Shui side and wind side, according to Heat balance principle and preservation of energy row write the differential equation；

Step 3: the differential equation write according to row carries out Laplace transformation, processes the Controlling model obtaining indoor thermal environment.

The method setting up indoor thermal environment load model the most according to claim 1, it is characterised in that in described step 1, institute State influence factor and be mainly the heat transfer of body of wall and accumulation of heat and indoor equipment and the situation of personnel, listed by the differential equation write be: Wherein, C_zThermal capacitance for air-conditioning regulation and control room, it is simply that air Specific heat capacity is multiplied by the volume in room, T_zFor the temperature in room, Q_aFor being supplied to the energy in room, Q by air conditioning system_w1For thing Energy needed for the change of direction body of wall own temperature and the energy sum exchanged by the heat of this body of wall indoor and outdoor, Q_RFor roof Energy needed for own temperature change and the energy sum exchanged by the heat of this body of wall indoor and outdoor, Q_w2For North and South direction body of wall The energy of own temperature change and the energy sum exchanged by the heat of this body of wall indoor and outdoor, Q_rFor indoor equipment and personnel couple The energy of indoor offer.

The most according to claim 2, the method setting up indoor thermal environment load model, it is characterised in that described variations in temperature Required energy determines according to below equation:

East-west direction wall:Wherein, C_w1Needed for raising 1 DEG C for east-west direction wall temperature Energy to be absorbed, Q_w1zThe energy transmitted to east-west direction wall for indoor, Q_w1oThe energy transmitted to east-west direction wall for outdoor, T_w1Temperature for east-west direction wall；

North and South direction wall:Wherein, C_w2Needed for raising 1 DEG C for North and South direction wall temperature Energy to be absorbed, Q_w2zThe energy transmitted to east-west direction wall for indoor, Q_w2oThe energy transmitted to east-west direction wall for outdoor, T_w2Temperature for North and South direction wall；

Roof:Wherein, C_RThe energy absorbed required for raising 1 DEG C for roof temperature, Q_RzFor The indoor energy to roof transmission, Q_RoThe energy transmitted to roof for outdoor, T_RTemperature for roof.

The method setting up indoor thermal environment load model the most according to claim 1, it is characterised in that in described step 2, only The air of surface cooler and the initial state of water and loss are carried out Main Analysis, it is assumed that the variations in temperature of surface cooler self and confession Air temperature change is identical, then arranging the differential equation write is:Wherein, C_ahCold for table Device temperature raises 1 DEG C of required energy, Q_wFor being supplied to the energy of surface cooler, Q for backwater_1ossFor surface cooler self loss Energy, Q_aThe energy taken away inside surface cooler for new wind, namely the energy in room, T it is supplied to by air conditioning system_sFor air feed Temperature.

The method setting up indoor thermal environment load model the most according to claim 1, it is characterised in that in described step 3, right The differential equation write of row, utilizes Laplace transform and solves system of linear equations and obtain between room temperature and each influence factor Relational expression:

Wherein, G₁Initial temperature and the relation of room temperature, G for room₂Initial temperature and room temperature for east-west direction wall Relation, G₃Initial temperature and the relation of room temperature, G for North and South direction wall₄Initial temperature and room temperature for roof Relation, G₅Change in flow and the relation of room temperature, G for water₆For the relation of outdoor temperature change with room temperature, G₇For supplying Return water temperature change and the relation of room temperature, T_z(0) it is the initial temperature in room, T_w1(0) it is the initial warm of east-west direction wall Degree, T_W2(0) it is the initial temperature of North and South direction wall, T_R(0) it is the initial temperature on roof,Stream for air-conditioner water system water Speed,For outdoor dry-bulb temperature,Difference for supply and return water temperature.

The method setting up indoor thermal environment load model the most according to claim 1, it is characterised in that to the thermal environment set up Model, utilizes the truthful data gathered to verify, and utilizes parameter tuning method to carry out pid control.