A Mathematical Model of an Automated Control System for Heat
Regulation in a Building
FARIDA TELGOZHAYEVA1, MUSLUM ARICI2, MURAT KUNELBAYEV3, GULNUR
TYULEPBERDINOVA1, ZHANARA SPABEKOVA1, AINAGUL BERDYGULOVA4,
YERALY SHAKEN5
1Al Farabi Kazakh National University, al-Farabi Ave, 71, Almaty, 050040, KAZAKHSTAN,
2Kocaeli University, Umuttepe Campus, Izmit, 41001, TURKEY
3Institute of Information and Computer Technologies, st. Pushkin 125, Almaty, 054000,
KAZAKHSTAN,
4Almaty Kazakh Alai khan University of International Relation and World Languages, st.
Muratbayeva, 200, Almaty, 050012, KAZAKHSTAN,
5Almaty Technologycal University, st. Tole bi, 100, Almaty, 050012, KAZAKHSTAN
Abstract: - In this study, a mathematical model of an automated control system for heat regulation in a building
was developed. A method of mathematical modeling of the centralized heating control system based on
mathematical models of distributed power systems and experimental studies has been developed, which allows
for determining the parameters of the coolant when the outdoor temperature changes, qualitative regulation of
heat in autonomous sources, quantitative regulation in automated individual heating devices, etc. The method
makes it possible to study the interaction of an automated individual heating point to increase the efficiency of
the management of distributed power systems of buildings. As a result of studying the controller created by the
R2 control unit, for the PI controller, the calculated heat consumption of the building imperceptibly increases
from 1.08502 kJ to 1.085888 kJ when an oscillatory transient occurs, and for the I controller, the calculated
heat consumption of the building remains at the same level. The level, as for the PI controller, increases slightly
during the oscillatory transition from 1.08456 GJ to 1.08535 GJ.
Key-Words: - individual heat point, automatic regulation, mathematical modeling
Received: October 26, 2022. Revised: July 6, 2023. Accepted: August 5, 2023. Published: September 7, 2023.
1 Introduction
In an intelligent heating system, the heating system
element requires intellectualization. Accurate
calculations are necessary to ensure heat supply and
energy saving. The development of mathematical
models directly affects the user's convenience and
economical operation of the heating system.
In, [1], the operation of heating systems was
investigated, in addition to monitoring and adjusting
the operating parameters, it is necessary to
coordinate the heat supply in accordance with the
season, outdoor air temperature, and the user's heat
needs to adapt the purpose of heat from the heating
system. In, [2], a heating system was investigated,
which is designed to supply electricity at various
temperature loads, protecting users from incredibly
high or low temperatures in the house, guaranteeing
the satisfaction of users' needs for heat, and
avoiding unnecessary heat costs to ensure
economical maintenance of heating systems. Several
studies have been conducted on optimizing the
operation of heating systems, in which the main
focus was on creating mathematical models of water
supply temperature, fuel consumption, and outdoor
air temperature, as well as regulating water supply
temperature and fuel consumption.
In, [3], they developed a mathematical model of
the heat point and found that to adapt to changes in
heat load, frequent regulation of the water supply
temperature can reduce operating costs, but they
certainly did not focus on the frequency with which
the water supply temperature was regulated.
In, [4], an optimization method was used for
controls in the heating mains network region, and it
was found that the optimization effect was different
when the water supply temperature was regulated at
different frequencies. In addition, the choice of the
control cycle was an important part of the
forecasting problem, [5].
In the article, [6], we checked the operation of
the thermal system and found that, compared with
traditional control, a significant temperature
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DOI: 10.37394/23203.2023.18.23
Farida Telgozhayeva, Muslum Arici,
Murat Kunelbayev, Gulnur Tyulepberdinova,
Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
E-ISSN: 2224-2856
231
Volume 18, 2023
discrepancy between the main supply and return
water is possible to reduce pump consumption and
increase overall fuel efficiency.
In, [7], a mathematical and dynamic model of
the heating network was developed; based on this
modification, the peak valley method and the ratio
analysis method were introduced, respectively, and
it also became possible to calculate two important
parameters related to the dynamic data of the
heating system - the delay time and the degree of
comparative attenuation. In, [8], a hydraulic pump
was compared with the classical main circulating
pump with an adjustable rotation speed in the
heating system, which can save at least 20% of
energy. In particular, when using a pump with a
distributed unstable speed with a low flow rate,
more energy could be saved. In, [9], a method for
controlling the radiator system was created based on
mathematical research and computer modeling. By
finding a rational combination of water supply
temperature and flow rate in the heating system, a
low temperature of the main recurrent water was
obtained, which allowed to reduce operating costs.
In, [10], a mathematical model was developed for an
integrated direct heat supply system that combines
wind energy, solar energy, natural gas, and
electricity. By approving a purposeful function of
rational management behavior under time-
consuming operational constraints, it was allowed to
minimize fuel consumption and increase the
efficiency of the system. In, [11], [12], [13], the heat
storage capacity of the district heating system was
adapted to the large size of the renewable energy
conversion in the system, which improved the
flexibility and efficiency of the system. Basing on
the monitoring of outdoor air temperature and the
history of scientific and technical data. In, [14], a
mathematical distribution model was created and an
error-free optimizer was developed to minimize
pumping costs and heat costs; by optimizing the
water supply temperature and fuel consumption, the
heating design could do efficiently and smoothly.
In, [15], presented all possible approaches to simple
forecasting of district heating networks to optimize
using a mathematical model. In, [16], the analytical
solution of Fourier and non-Fourier models of heat
transfer in a longitudinal rib in the presence of
internal heat release under a periodic boundary
condition is studied. The entire review is given in
the dimensionless form. These two mathematical
models were solved analytically using the Laplace
transform method. The temperature distribution in
the longitudinal edge is measured using the
residuals in a single plane theorem for the inverse
Laplace transform method. The nature of the
temperature wave is revealed at a small value.
The temperature of the longitudinal edge is
evaluated for various parameter values relative to
the spatial coordinate. The effect of the variability
of various parameters on the temperature
distribution in the rib has been thoroughly studied. It
has been observed that the cooling process proceeds
quickly in a Fourier-free model compared to the
Fourier model. Asymptotic methods are widely used
in mathematical modeling of a thermal object. When
describing the processes of heat propagation in a
solid, three stages are distinguished. One of them is
called the regular mode stage, which exists with a
sufficiently large change in the process over time.
Asymptotic methods are used, for example, in
studies of regular thermal regimes corresponding to
a developed stage of the process. Asymptotic
methods have found application in the propagation
of heat transfer processes not only in weakly curved
rods, and cylinders of variable cross-sections but
also in studies of composite materials, [17]. The
paper presents an abbreviated analysis of various
numerical methods applicable to the Casson fluid,
based on the study of various kinds of experimental
work over the past 10 years. Previous studies,
outlined in various versions by various researchers,
are used as a key source of information about
numerical methods used to solve control equations.
The study is generally useful when searching for
literature that studies the effect of the necessary
control parameters on Casson flow profiles.
In addition, comparisons with classical methods
are provided, and the results are carefully checked.
It may be noted that some longstanding methods
among all the various varieties of numerical
methods are stable and well-known among
researchers, such as the shooting technique, the
Runge-Kutta method, the Keller Box method, etc.
The results are tested in each of these cases, [18].
The purpose of this study is to develop a
mathematical model of an automated control system
for heat regulation in a building, differs in that the
control unit is based on the calculated transient
characteristics of the serial connection of the control
object and the temperature sensor, it is also possible
to determine the parameters of the coolant with
possible changes both in the structure of the
elements of an automated individual heating point
and in the systems heating of a building or structure.
2 Research Methodology
The advantage of this analysis lies in the fact that
when developing automated individual heating
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Farida Telgozhayeva, Muslum Arici,
Murat Kunelbayev, Gulnur Tyulepberdinova,
Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
E-ISSN: 2224-2856
232
Volume 18, 2023
points of houses, the use of heat by the building in
accordance with standard standards is located
perfectly at the same level, and, therefore, there is a
possibility of utilitarian use of the I-regulator to
regulate the flow of heating of premises and
buildings, because it is easier to introduce and
configure. It is also possible to say that the present
study of the transient motion, taking into account
the temperature of the coolant in the return pipeline
of the structure, shows that an ultra-low-frequency
filter arrives under control concerning full-fledged
oscillations at its inlet (in the output pipeline). In
contrast to the known methods of finding the
controller parameters, the control source is based on
the calculated transient characteristics of the
alternating combination of the control object and the
temperature sensor.
Using the studied mathematical model, it is
possible to establish not only suitable options for the
control unit but, above all, the characteristics of the
coolant with probable changes both in the structure
of components of an automated personal heating
point and in the heating systems of a building or
structure.
In this paper, the features of the control of an
automated IHP with known standard regulators are
investigated using mathematical modeling. The heat
supply system is a complex of distributed heat
exchange devices integrated into the whole system
of generation, transportation, and consumption of
thermal energy. The elements of the water heat
supply system are divided by types of heat transfer
(convection, thermal conductivity, radiation) and by
design (direct current, counterflow, combined
current). If we neglect a small change in the mass of
the coolant, then the rate of change in its
temperature will be proportional to the amount of
heat:
1
1
2
2
1
1
1
TT
(t)
k r f m
n
k i i i i
i
ni
ii
ii
n
r i i
i
n
f fi i i i
i
cmdT Q Q Q Q Q
QF
T
QF
x
Q F q
Q k F T T

(1)
where
, , , ,
k r f m
Q Q Q Q Q
the total costs by
convection, thermal conductivity, radiation, and
filtration,
m
Q
-heat source,
-heat capacity, m-
mass of the medium,
i
-heat transfer coefficient,
F
-heat exchange surface,
i
-thermal conductivity
coefficient of the medium,
x
-spatial coordinate,
(t)
i
q
-specific heat flux,
fi
k
-filtration heat transfer
coefficient.
The expression dT in the first equation (1) is a
differential:
ii
i
i
TT
dT w
tx



(2)
For each of the elements of the heat supply system,
it is possible to obtain a system of partial differential
equations by substituting the values in the
expression (1).
v
x y z
Q
T T T T
w w w T
t x y z cp cp
(3)
222
2 2 2
TTTT
x y z

(4)
where T is the temperature of the coolant, t-time,
T
-coefficient of thermal conductivity, c-heat
capacity of the coolant, p-density of the coolant,
,,x y z
-coordinates,
,,
x y z
w w w
-projection of the
velocity vector of the coolant,
-Laplace operator
in a rectangular coordinate system. In the case of
solids, a differential equation of the thermal
conductivity of the form is applied:
2v
Q
TT
t cp cp
(5)
where
T
,c,
p
- coefficient of thermal
conductivity, heat capacity, and density of the body.
For the uniqueness of the solution of equations (3)-
(5), geometric, physical, boundary, and time
conditions should be supplemented. Geometric
determine the size and shape of the body, physical
includes numerical values and the nature of changes
in the thermophysical parameters of the body and
the environment, the intensity of internal heat
sources. Boundary conditions determine the
conditions of heat exchange at the body's boundary,
temporarily set the nature of changes in
temperature or heat flow at the initial and final time.
Suitable differential equations follow from
conservation laws, while the material is considered a
continuous continuous medium, the characteristics
of the transfer processes are represented by constant
functions of coordinates and time.
To study the non-stationary problems of forced
convective heat transfer, a differential equation
describing heat transfer in a moving medium with a
constant velocity is used. The structure of a typical
automated IHP of a heating system to a heat source,
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DOI: 10.37394/23203.2023.18.23
Farida Telgozhayeva, Muslum Arici,
Murat Kunelbayev, Gulnur Tyulepberdinova,
Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
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Volume 18, 2023
shown in Figure 1, contains a process controller
TC1, a block of circulation pumps C1 and C2 with
electric drives ED1 and ED2, a control valve RV1
with an actuator A1, a check valve BV1, a direct-
acting differential pressure regulator PR1 with an
RV2 valve, temperature sensors of the coolant DT1
and TG2 accordingly, in the supply and return
pipelines, pressure sensors PT1 and PT2, an outdoor
temperature sensor TG3, as well as a thermal energy
metering unit, for example, a heat meter with a set
of sensors.
Fig. 1: Block diagram of an automated IHP building
A generalized functional diagram of the heating
system of an automated building IHP is shown in
Figure 2. The circuit contains the following
elements: WC weather compensation unit
(interference control); CU control unit (deviation
control, Figure 2.); PU protection unit (control of
the permissible temperature range of the coolant in
the return pipeline);
BS - logic control unit switching input signals
and depending on temperature; Elements CE1
CE3 converters of output values (resistances) of
temperature sensors S1 S3 to the physical
quantities (temperatures) measured by them; the
actuator in the form of an electric motor with a
constant speed of rotation of the shaft; the regulating
body V - in the form of a seat valve; the heating
element of the mixing unit carriers MK (mixing
unit) (Figure 2) from the connected heating
networks and the return pipeline of the building
heating system through a jumper with a check valve;
the control object is CO (control object), which is
the building heating system (HS).
Designations of the main values of the
functional scheme: outdoor air temperature;
converted outdoor air temperature; calculated
temperature of the coolant in the supply pipeline of
the building heating system; control deviation of
the coolant temperature in the supply pipeline of the
building heating system (set by the user to the
dispatcher for correction); ε temperature deviation
from the set value;
2
x
control signal of the control
unit;
output signal of the switching unit;
3
x
reduced value of the movement of the regulatory
body;
1
G
calculated flow rate
1
T
the temperature
of the coolant at the entrance to the IHP, formed by
the boiler power plant, depending on; and is the
temperature of the coolant, respectively, in the
supply and return pipelines of the heating system
(SS) city. buildings;
*
01
T
and
*
02
T
converted
temperatures and, respectively; R1-R3 output
resistances of temperature sensors S1-S3;
1
u
and
2
u
control signals of the PU unit, which set the
movement of the actuator A in the direction of
opening or closing the regulatory body V,
respectively;
u
output signal of the PU unit.
Fig. 2: Functional diagram of an automated IHP
building
The designations of the main values of the
functional scheme are as follows:
a
T
- the initial
outdoor temperature;
*
a
T
- outdoor air temperature at
the entrance to the unit R1;
co
T
- the calculated
temperature of the coolant required in accordance
with the principle of weather compensation in the
supply pipeline from the building after the jumper
HS the check valve (Figure 1);
3
T
- calculated
deviation of the coolant temperature in the supply
pipeline HS of the building, set by the dispatcher in
order to correct
co
T
;
T
- temperature deviation
of the controlled value
01
T
;
- the given control
signal of the controller R2;
- the reduced value of
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Farida Telgozhayeva, Muslum Arici,
Murat Kunelbayev, Gulnur Tyulepberdinova,
Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
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the movement of the regulatory body (RB);
01
G
-
the flow rate of the coolant after the RB, i.e. before
the jumper with the check valve;
01
T
- the
temperature of the coolant in the supply pipeline of
the internal circuit RB of the building;
*
01
T
- the
measured temperature of the coolant in the building
heating system;
02
T
- the temperature of the coolant
in the return pipeline heating systems of the
building;
*
02
T
- the measured temperature of the
coolant at the inlet to R2.
A mathematical model of a building HS based on an
automated IHP in accordance with the functional
scheme and taking into account the structures of
regulators R1 and R2 (to simplify the scheme in
Figure 2, their structures are not disclosed) is
presented in the form of a system of equation (6).
System (1) includes the following equations:
Equations of motion of temperature sensors S3 and
S1
**
a
da a da
dT (t)+T (t)= k T(t),
dt
(6)
**
01
d1 01 d1 01
dT (t)+T (t)= k T (t),
dt
(7)
Equations for regulators R1 and R2 (equation of the
heating schedule for calculating the design
temperature of the coolant in the supply pipeline of
the building HS
co
T
*
co 1 a
T (t)= f (T )
(8)
Coupling equations for determining
T
*
co 3 01
T(t)=T (t)+T (t)-T (t)
(9)
Equations of the R2 controller for control in heat
supply systems
(dd
11d
0, - X T(t) X
x T) k T(t), T(t)> X


(10)
Nonlinear equation of the restriction zone
m1
1u
p
kdx ( T)
(t)= x ( T)T +
X dt



(11)
The equation of the actuator
,
, ( )
2 m m
2mm
k (t) k (t) k
x (t) k t k

(12)
The equation of the regulator of the organ
concerning the output value
01
G
u2
u
k
d (t) x (t)
dt
(13)
Coupling equations for the mixi
2
k (t)
01 1 k
G (t)=G k e
(14)
Equation of motion of the CO through the control
channel
1 01 02 co 01 co 01
TG (t)+T (t)(G -G (t))=G T (t)
(15)
Equations of motion of the temperature sensor S2
2
**
02
d 02 d2 02
dT (t)+T (t)= k T (t)
dt
(16)
1 2 1 2
()
202 02 02 01
2
d T (t) dT (t)
+ +T (t)= kT (t)
dt dt
(17)
The equation for determining the value of thermal
power
01 1 02 02
W(t)=G (t)T (t)-G (t)T (t)
(18)
Additional designations in the system of equations
(6) are as follows:
di
and
di
k
- accordingly, the time
constant and the transmission coefficient of the i-th
temperature sensor;
co
G
is the flow rate of the
coolant in the internal circuit of the building HS,
determined by the circulation pump (Figure 1);
1
G
-
nominal flow rate of the coolant at the inlet of the
RB;
1
T
- the temperature of the coolant in the
supply pipeline at the input to the IHP;
(
1
x T)
-the
output value of the nonlinear dead zone of the
regulator R2;
2
x (t)
- the output value of the
nonlinear restriction zone (saturation) in the R2
regulator;
1
k
and
2
k
the proportionality
coefficients, respectively, of the nonlinear dead
zones and the limitations of the regulator R2;
d
X
-
the dead zone of the regulator R2;
p
X
- the
proportionality zone of the regulator R2;
u
T
- the
constant of the regulator R2.
3 Results
Based on the mathematical model of building HS,
the equation for determining the value of the
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Farida Telgozhayeva, Muslum Arici,
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Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
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thermal power
W(t)
in a building, taking into
account the use of an automated IHP, is as follows:
01 1 02 02
W(t)=G (t)T (t)-G (t)T (t)
(19)
Simulation parameters. We believe that at the initial
moment of time
t =0
, the automated Individual
heating point of the building is switched to the
reduced heat consumption mode by reducing
co
T
by
0
5c
.
The initial parameters for modeling are presented in
Table 1.
Table 1. Initial parameters for modeling
Name of the parameter, its
designation
Dimension
value
conversion coefficient of the
controlled object,
k
0.807
the time constant of the
control object,
1
1337 s
the time constant of the
control object,
2
759 s
the initial temperature of the
coolant in the system,
2
T
48 0
the maximum flow rate at the
commissioning of an IHP,
1
G
14.7 m3/h
maximum consumption in
building HS,
co
G
16 m3/h
outdoor air temperature,
a
T
-1 0
the initial position of the
actuator valve stem
74.6%
controller parameter R2,
m
k
100%
controller parameter R2,
d
X
0
The main characteristics of time sensors are
presented in Table 2.
Table 2. Time constants of temperature sensors
Sensor type
Purpose and
symbol.
Magnitude,
dimension
ESMU-100
Submersible
copper coolant
temperature
sensor in the
sleeve,
d1
32 s
ESMT
Outdoor air
temperature
sensor
900 s
The main characteristics of the control valve of the
VB2 CB are presented in Table 3.
Table 3. Characteristics of the VB2 control valve
Name of the parameter,
its designation
Magnitude,
dimension
diameter,
v
D
40 mm
ratio,
kvs
k
25 m3/h
conditional pressure,
v
P
2.5 МPa
temperature,
min
T
5 0С
temperature,
max
T
150 0С
rod stroke,
h
10 mm
The technical characteristics of the AME 20 type
actuator for operation with the VB2 control valve
are presented in Table 4.
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Farida Telgozhayeva, Muslum Arici,
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Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
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Volume 18, 2023
Table 4. Characteristics of the AME 20 actuator
The name of the
parameter, its
designation
Magnitude,
dimension
voltage
24 V
frequency
50/60 Hz
power consumption
4 Wt
type of control signal
analog
developed force
450 N
stroke of the rod
10 mm
time of movement of
the rod by 1 mm
15 s/mm
input signal 1
0-10 V, R1=24 kOm
input signal 2
0-20 mА;
i
R
=500
kOm
input signal
0(2)-10 V
the presence of a return
spring
no
minimum ambient
temperature
0
maximum ambient
temperature
55 0С
The proportional-integral law of regulation (PI -
regulator) formed by the control unit R2 of the
controller with the use of an executive mechanism
of the AME 20 type is investigated.
The equations of motion of the control unit R2 have
the form (see the system of equations (6)):
m1
1u
p
kdx ( T)
(t)= x ( T)T +
X dt



(20)
where
p
X
=
80
С,
u
T
=10 s. The initial equation
(20) in the PI-controller is then integrated by the
executive mechanism. This is an important feature
of the controller in question.
The result of simulation modeling taking into
account the
p
X
and
u
T
data for this research
variant is shown in Figure 3.
Fig. 3a: Dynamic characteristics in the form of
changes in the temperature of the coolant
01
T
at the
input with the building HS on an increased time
scale
Fig. 3b: Temperature of the coolant
02
T
in the return
pipeline at the outlet of the building heating systems
As can be seen from Figure 3a and Figure 3b
analysis of the studied dynamic characteristics in the
form of changes in the temperature of the coolant
01
T
at the input from the building HS on an
increased time scale (Figure 3a) and the temperature
of the coolant
02
T
in the return pipeline at the outlet
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Farida Telgozhayeva, Muslum Arici,
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Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
E-ISSN: 2224-2856
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of the building heating systems (Figure 3b) shows
that they have the form of aperiodic transients.
a)
b)
Fig. 4: Dependence of changes in
01
T
(a) and
02
T
(b)
of building HS
As can be seen from Figure 4a and Figure 4b, the
estimated heat consumption of the building is about
1.08502 Kj. We increase the time in equation (7),
i.e. we take it equal to 60 s.
Analysis of the studied dynamic characteristics
in the form of changes in
01
T
at the input to the
heating systems of buildings on an increasing time
scale (Figure 4a) and the temperature of the
02
T
coolant in the return pipeline at the outlet of the
building HS (Figure 4b) shows that a transient
oscillatory process is observed for
01
T
. The
estimated heat consumption is about 1.0858 GJ.
The integral law of regulation (I-regulator) formed
by the control unit R2 of the controller using a
similar actuator is investigated. In this regard, the
equation of motion of the control unit R2 is replaced
in the system of equations (6) by an equation of the
form:
m1u
p
k
(t)= x ( T)T
X
(21)
where
80 С
p
X
,
20
u
Ts
. The initial equation
(21) in the I-regulator is then integrated by the
actuator. The simulation results for this variant are
shown in Figure 5.
a)
b)
Fig. 5: Dependences of changes
01
T
(a) and
02
T
(b)
of the building HS с.
Figure 5 shows an analysis of dynamic
characteristics in the form of changes in the
WSEAS TRANSACTIONS on SYSTEMS and CONTROL
DOI: 10.37394/23203.2023.18.23
Farida Telgozhayeva, Muslum Arici,
Murat Kunelbayev, Gulnur Tyulepberdinova,
Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
E-ISSN: 2224-2856
238
Volume 18, 2023
temperature of the
01
T
coolant at the input to the
building heating systems on an increased time scale
(Figure 5a) and the temperature of the
02
T
coolant in
the return pipeline at the outlet of the building
heating systems (Figure 5b) shows that an
oscillatory transition process is observed for. The
estimated heat consumption of the building in the
studied case is about 1.08535 GJ.
In equation (3) we take the following parameter
values:
100 С
p
X
,
1
u
Ts
. During all studies,
the values of
u
T const
were selected, taking into
account that
u
T
is greater or less than the time of
movement of the valve stem using the actuator
(Table 4). The simulation results taking into account
the selected values of
p
X
and
u
T
are shown in
Figure 6.
a)
b)
Fig. 6: Dependences of changes
01
T
(a) and
02
T
(b)
of the building HS
Figure 6 shows an analysis of the studied dynamic
characteristics in the form of changes in
01
T
at the
input to the heating system of the building on an
enlarged time scale (Figure 6a) and the temperature
of the coolant
02
T
in the return pipeline at the outlet
of the building HS (Figure 6b) shows that they have
the form of aperiodic transients. As expected, the
estimated heat consumption of the building
decreased to 1.08456 GJ.
A comparative analysis of the results obtained for
the studied 2 control laws formed by the control unit
R2 of the controller using an AME 20 type actuator
with different parameters of the controller unit
showed the following:
1) for the PI controller, the calculated heat
consumption of the building increases slightly from
1.08502 Gj to 1.08588 GJ when an oscillatory
transient occurs;
2) for the I-regulator, the calculated heat
consumption of the building is at the same level as
for the PI-regulator and increases slightly with an
oscillatory transient from 1.08456 GJ to 1.08535 GJ.
Transient processes of an oscillatory type for the
actuator should be excluded since they lead to
premature failure of the electric motor of the
actuator. To eliminate the oscillatory processes that
have appeared in the automatic control system of the
automated individual heat pump during the
processes under study, it is necessary to change the
tuning parameters of the regulator taking into
account the specified time of movement of the rod
using the actuator.
At the initial moment of time t = 0, the automated
ITP is switched to the reduced heat consumption
mode by reducing the temperature by 5 ° C (due to
the deviation. The duration for the studied cases is 1
h. 45 min. Since the coolant mixing unit is
characterized by significantly less inertia compared
to the building heating system, the actual
temperature
T
and the value of its deviation e from
the calculated temperature in the heating system.
Analysis of the temperature change Toi in the
supply pipeline of the heating system shows that the
duration of the transition process through the control
channel does not exceed 5 minutes. The duration of
the transition to a new steady state of the water
temperature in the return pipeline exceeds 1.5 hours
and is determined by transients in the heating
system of the building. Consequently, transients in
the coolant mixing unit can be neglected. In the case
under study, the temperature overregulation is
WSEAS TRANSACTIONS on SYSTEMS and CONTROL
DOI: 10.37394/23203.2023.18.23
Farida Telgozhayeva, Muslum Arici,
Murat Kunelbayev, Gulnur Tyulepberdinova,
Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
E-ISSN: 2224-2856
239
Volume 18, 2023
0.93%, and the total calculated thermal energy
consumption is 1.16256 GJ. Analysis of the
characteristic G shows that in the mode of reduced
heat consumption, when working out the commands
of the BR unit using the AME 20 actuator through
the VB 2 control valve, the flow rate G initially
almost instantly decreases to 3.7 m'/h (53.3%), and
then, according to the exponential law, partially
increases to 5.54 m'/h (79.8%). This is due to the
operation of the regulator and a decrease in the
temperature of the coolant G02 in the return pipeline
of the building heating system. Analysis of
temperature changes in the supply pipeline of the
building heating system shows that the process has
become oscillatory, and the nature of the transition
process for the temperature in the return pipeline has
not changed. At the same time, the over-regulation
for the temperature of G01 is 6.25%, and the total
estimated thermal energy consumption is 1.08502
GW. A comparative analysis of dynamic processes
for the automated ITP under study with various
actuators shows that an increase in the speed of the
actuator based on the AME 30 leads to the operation
of its electric motor in the mode of frequent
operation, however, transient processes of the
oscillatory type in the system should be excluded,
because they contribute to the premature failure of
the IM electric motor. Therefore, when changing the
heat consumption mode of a building, it is necessary
to change the tuning coefficients of the BR control
unit.
4 Discussion
The developed mathematical model of the building
heating control system in the form of a block
diagram takes into account the features of the
mathematical models of the elements and their
nonlinear characteristics in the structure of the
regulator with an integrated actuator, switching
units, and a regulatory body, as well as the
nonlinearity in the area of mixing of heat carriers in
the heating point. The model allows us to study the
processes occurring in the heating system of a
building with an automated when controlling and
disturbing influences change. The developed
method of mathematical modeling of the control
system for decentralized heating of a complex of
buildings, based on mathematical models of
distributed power systems and experimental studies,
allows determining the parameters of the coolant
when the outdoor temperature changes, qualitative
regulation of heat in autonomous sources,
quantitative regulation in automated, etc. The
introduction of automated ITPS for buildings with
the highest thermal load leads to noticeable savings
in thermal energy under various operating modes of
heat consumption systems. Thus, during dynamic
processes in the thermal points of the building
complex, significant fluctuations in the values of
thermal power are observed, determined by changes
in the flow rate of the coolant and the temperature
difference in heating systems. This mathematical
model allows you to determine the values of the
coolant when the outdoor temperature changes,
better heat regulation in autonomous sources,
numerical control in automated individual heating
devices, etc. The method allows you to study the
coordination of an automated separate heating point
to increase the performance of managing distributed
power systems of buildings.
5 Conclusion
The possibilities of mathematical modeling of the
control of an automated individual thermal point of
a building with well-known standard regulators are
presented. When creating automated individual
heating points of buildings, it is necessary to take
into account the results obtained, which showed that
the heat consumption of a building under standard
regulatory laws is approximately at the same level
and therefore there is a possibility of the practical
application of an I-regulator to regulate the heating
process of a building since it is easier to implement
and configure.
The analysis of the transient process taking into
account the temperature of the coolant in the return
pipeline of the building shows that the control object
is a low-frequency filter with respect to significant
fluctuations at its input (in the supply pipeline).In
contrast to the known methods for determining the
parameters of the controller control unit based on
the calculated transient characteristics of the serial
connection of the control object and the temperature
sensor using the developed mathematical model, it
is possible to determine not only the optimal settings
of the control unit but first of all, the parameters of
the coolant with possible changes both in the
structure of the elements of an automated individual
heating point and in the heating systems of a
building or structure.
WSEAS TRANSACTIONS on SYSTEMS and CONTROL
DOI: 10.37394/23203.2023.18.23
Farida Telgozhayeva, Muslum Arici,
Murat Kunelbayev, Gulnur Tyulepberdinova,
Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
E-ISSN: 2224-2856
240
Volume 18, 2023
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DOI: 10.37394/23203.2023.18.23
Farida Telgozhayeva, Muslum Arici,
Murat Kunelbayev, Gulnur Tyulepberdinova,
Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
E-ISSN: 2224-2856
241
Volume 18, 2023
Contribution of Individual Authors to the
Creation of a Scientific Article (Ghostwriting
Policy)
-Farida Telgozhayeva and Murat Kunelbayev
carried out the simulation and the optimization.
-Zhanara Spabekova and Gulnur Tyulepberdinova
have implemented the concept.
-Ainagul Berdygulova was responsible for the
Statistics.
Sources of Funding for Research Presented in a
Scientific Article or Scientific Article Itself
No funding was received for conducting this study.
Conflict of Interest
The authors have no conflicts of interest to declare.
Creative Commons Attribution License 4.0
(Attribution 4.0 International, CC BY 4.0)
This article is published under the terms of the
Creative Commons Attribution License 4.0
https://creativecommons.org/licenses/by/4.0/deed.en
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WSEAS TRANSACTIONS on SYSTEMS and CONTROL
DOI: 10.37394/23203.2023.18.23
Farida Telgozhayeva, Muslum Arici,
Murat Kunelbayev, Gulnur Tyulepberdinova,
Zhanara Spabekova, Ainagul Berdygulova, Yeraly Shaken
E-ISSN: 2224-2856
242
Volume 18, 2023