Performance of 220kV Transmission Line Calculation for

First International Conference on Modern Communication & Computing Technologies (MCCT'14)
Performance of 220kV Transmission Line Calculation for
Diverse Operating Conditions for Smart Power Bulk
Transfer
Muhammad Usman Sardar1*, Mazhar Hussain Baloch1 , Ghulam Sarwar Kaloi1 , and
Dr. M.Usman Keerio2
1
The Islamia University of Bahawalpur, Punjab, Pakistan
[email protected], [email protected],
[email protected]
2
Quaid-awam University of Engineering, Science and Technology, Nawabshah, Pakistan
[email protected]
Abstract. This research paper employs to calculate the transmission line performance and methodology is being applied to smart power bulk transfer, aiming to increase the power carrying of network during transmission of 220 kV
systems. Matlab algorithms are technologically advanced to perform the theoretical simulation of loadability using higher technical considerations. Compensations of transmission line parameters like Inductance, capacitance and leakage
conductance are considered for the higher degree of network in comparison
with deregulated utility environment. . Load current, power factor & all the parameters collectively determine the electrical performance of transmission line.
Performance includes calculation of the sending end voltage, current, power
factor, power losses, efficiency in the transmission, and regulation of the line
and limits of the power flow in the steady state. The effect of different load
power factor, current carrying capacity and voltage stability of end line, active
& reactive power is observed. Improvement achieved by using shunt & series
compensation is observed and a suggestive solution is given out for installing
the static volt-ampere reactive compensation mechanism.
Keywords: modeling of medium & long transmission lines, series and shunt
compensation, performance calculation
1 Introduction
High voltage electric transmission is the bulk transfer of electrical energy, from
generating plants to substations located near to population centers. Transmission
lines, when interconnected with each other, become high voltage transmission networks. Practicalities around the world are working together for innovation with new
and smart techniques for electrical power transmission more efficiently than before
[1]. The Smart transmission system seems to become the next occurrence of the smart
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First International Conference on Modern Communication & Computing Technologies (MCCT'14)
idea. Most of the advanced technologies have been predicted with an innovative system, which are not a new curved on the electrical transmission system environment.
The distributed generation enables us to become an essential part of a wholly new
electrical system where new well-regulated method will operate to make smart system
[2]. The smart electrical grid systems are implemented throughout the world but other
than Pakistan and focusing on the smooth electrical communication and composition
on top of the existing setup [2].Generally, electrical transmission & distribution systems were maintained by the same company, according to the report globally separation of the electricity transmission business from the distribution business because
National Transmission & Dispatch Company (NTDC) is responsible only for large
power transmission in Pakistan. Transmission lines mostly use 3-Ф alternating current, although 1-Ф alternating current is sometimes used for traction load.
2
Literature reviews
Demirci, T, This research work is carried out through the National Power Quality
Project of Turkey. A new power system monitoring and control concept has been
proposed and designed to make the power quality regulations for the ETS implementable. The part of the system that is in operation in the ETS of Turkey, central
control of shunt reactors and capacitors, generation units and FACTS devices in the
transmission systems to enhancement of the transmission system reliability and stability [9].
Dirk Van Hertem, The strong growth and the expected further increase in generation in Europe require a fundamental upgrade of the transmission system. A potential
option is to realize these upgrades at a higher voltage by constructing a new overlay
grid or supergrid and by improving the efficiency. Such a super grid is likely to be
built using VSC DC system [10].
Westermann, Smart transmission seems to become the next instance of the smart
grid vision. However, most of the innovative technologies, which have been foreseen
for a smart distribution grid, are not totally new into the transmission system operation environment. Smart transmission becomes integral part of an entirely new power
system where new controllable device will operate to make transmission smarter. In
the last consequence a new network layer will be built which is referred to as an overlay grid in Europe [11].
Komoni V, This paper provide the possibility of installed the Unified Power Flow
Controller, FACTS devices on sending and receiving ends of 400 kV transmission
power system. Application of UPFC for control of the power system attributes and
flow has been explored in this study. The Matlab/Simulink environment is used to
simulate the model of interconnected transmission lines between three power systems
[12].
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3
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Electrical Parameters of Transmission Conductor
Conductance (G), Resistance (R), Inductance (L) & Capacitance (C) are the transmission parameters. The inductance and capacitance are the effects of magnetic and
electric fields around the conductors. The shunt conductance illustrates the leakage
current through insulators, which is very small and can be neglected. The Electrical
parameters are critical for the expansion of the transmission models for the analysis of
the power system during planning and operation stages. The power transmission lines
are represented by an equivalent model with approximate circuit parameters on per
phase basis. These typical ideas can be used to work out voltages, currents, power
flows, efficiency and voltage regulation.
4
Line Modeling and Performance Analysis
The electrical transmission network terminals are experienced as the power source
and sink respectively. The representation is governed by on instant power flow direction through switching numerous times during operation of an electrical power lines.
The nomenclature series impedance per length/phase, shunt admittance per
length/phase to neutral, inductance per length/phase, capacitance per length/phase,
resistance per length per phase length of the power line, total series impedance, total
shunt admittance/phase to neutral. The complex voltage and current values at one end
of power transmission lines are calculated by corresponding at its other side of the
power line. The design requires the parameters of the power transmission line.
5
Medium Line Model and Simulation
By considering the medium transmission Line Model for performance evaluation.
For medium the length is above 80 kilo meter. in this model the shunt admittance is
incorporated. The total shunt admittance is placed as shown in Fig.
IR
IS
Z/2
VS
Series
Compensation
Z/2
Series
Compensation
VR
Y
Shunt
Compensation
Fig. 1. T- model of medium transmission line
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First International Conference on Modern Communication & Computing Technologies (MCCT'14)
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The combine power transmission line relations are given as
VSE= A*VRE + B*IRE & ISE= C*VRE+D*IRE
(1)
A, B, C & D are the generalized circuit constant factors of an electrical transmission equivalent circuit. This model reflexes the approximate behavior of medium
transmission line. Where these constants, listed above, vary for the different an electrical transmission line scenario [5].
A= D=
, B= Z and C= Y
Efficiency=
(2)
(3)
Voltage regulation=
Angle sending= Voltage phasor angle – Current phasor angle
Active power= |VS| *|IS| *Cos (θ)
Reactive power= |VS| *|IS| *Sin (θ)
(4)
(5)
(6)
(7)
These are calculated. These equations are simulated using Matlab software for the
existing constants of transmission line circuits. The performance of the line can be
considerably improved by compensating the reactive part, either using series or parallel compensation type. Series compensation is the procedure of placing capacitors in
series with each conductor line. It effectively reduces the series impedance with effect
of ultimately lower voltage drop and higher Power transfer capability. Shunt or parallel compensation refers to placing the inductors from each line to neutral. The shunt
reactors are help in compensating the Ferranti effect under light load. Procedures
discussed above are added up here and results are simulated. The compensation factor
is ratio of reactance due to capacitor added up in series per phase divided by total
inductive reactance of the line per phase as in series branch i.e., XC/XL for series
compensation and same for shunt or parallel compensation. Following graph and
tabular data values are simulated results of percentage compensation of medium
(moderately long) transmission line for bulk power transfer. Consider a case study
taken from NTDC (National Transmission and Dispatch Company), Pakistan with
certain resemblance.
V=220 kV, Power =500e6; Frequency=50, Power Factor=.80, R=19.96, L=
0.2981; C= 3.191e-6;
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First International Conference on Modern Communication & Computing Technologies (MCCT'14)
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Graph. 1. Performance behavior of medium transmission line.
Calculated Values
500
450
400
350
300
250
200
150
100
50
0
V_send (kV)
Compensation Factor-
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
257 246.22234.95223.74212.65201.77 191.2 181.04171.43162.52154.26
P_reactive (Mvar) 317.71303.21287.42270.43252.31233.16213.05192.09170.36147.97 125
PF
0.56
0.58
0.6
0.63
0.65
0.68
0.72
0.75 0.7903 0.83
Voltage Regulation 1.13
1.03
0.91 0.802
0.7
0.61 0.5167 0.43
0.87
0.35 0.2881 0.22
Power Increase (%) 100 110.05112.44138.04158.14 184 221.13 271.9 341.94424.21468.48
Table 1. Performance behavior of sending voltage, current, active power (MW), power factor, power Increase for cumulative (series and shunt) compensation of medium transmission
Obviously, the performance of medium (moderately long) line is improved by
compensation of both types. With 80% compensation the power line can carry more
than 300 percent electrical power than rating capacity, 35% improved power factor,
and 69% improvement in voltage regulation, 60 % less reactive power from the supply side.
6
Long Transmission Line Model and Simulation
The Long Line Model and equations are simulated for evaluation of performance
behavior of transmission line. These lines are above 240 km in length. Using one
phase and neutral connection of 3-Ф line with impedance and shunt admittance of the
line is uniformly distributed.
I + dI
VS
V+ dV
z dx
Y dx
dx
I
VR
V
x
Fig. 2. Long transmission line one phase and neutral
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Load
First International Conference on Modern Communication & Computing Technologies (MCCT'14)
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instatntaneos values of current
instatntaneos value of voltage
The voltage current relations are given by VS= A*VRE + B*IRE & ISE=
C*VRE+D*IRE, A, B, C & D is the generalized circuit constant factors of electrical
transmission line equivalent circuit. This model reflexes the approximate behavior of
long transmission line. A=D=
, B= ZC cosh ) and C=
. Other attributes are calculated like in a similar pattern with equations described above. The voltage (or current) phasor is sum of incident and reflected voltage that is a positive and
negative term of general exponential signals. These phasor are function of distance
showing the variations and simulated here. Consider the case of electrical power
transmission system; the values simulated are taken from NTDC data. V=220 kV,
P=200e6, f=50, pf=0.9, V=220e3, P=50e6, R=9.5, C=.25e-6, L=201e-3 and
Z=R+j*XL-jXC*X, where x is per-unit compensation.
8
10
x 10
voltage phasor
5
0
-5
200
250
300
350
400
transmission line distance
450
500
6
2
x 10
current phasor
1
0
-1
-2
200
250
300
350
400
transmission line distance
450
Fig. 3. Voltage and current phasors of long transmission line
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500
First International Conference on Modern Communication & Computing Technologies (MCCT'14)
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Graph 2. Output Behavior of Different Parameter of Transmission Line with Series Compensation.
Table 2. Behavior of sending voltage, current, Efficiency, Power Increase for series compensation of long transmission line
Calculated Values
600
Compensation factor -
500
400
300
200
100
0
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
V_sending (kV)
150.79 148.78 146.83 144.94 143.11 141.34 139.65 138.03 136.48 135 133.61
I_sending (A)
553.21 554.01 554.81 555.6 556.39 557.19 557.99 558.79 559.58 560.38 561.18
Efficiency %
94.27 94.268 94.26 94.26 94.25 94.25 94.24 94.23 94.23 94.23 94.22
Power Increase % 100 110.57 123.58 139.93 161 189.12 227.78 282.7 360.92 457.73 512.59
Through series compensation we can effectively increase the power transmission
of line by reducing the value of B. The value of B has direct effect on power carrying
of line. With 80% compensation, the maximum power which can be transmitted is
increased by about 360% as we get 360 times less value of B in without compensation
scenario.
Graph 3. Output Behavior of Different Parameter of Transmission Line with Series Compensation.
Calculated Values
80
70
60
50
40
30
20
10
0
Power Factor
Voltage Regulation
Compensation factor 
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0.85
0.86
0.87
0.88
0.89
0.9
0.91
0.92
0.93
0.94
0.94
18.61 16.89 15.23 13.61 12.06 10.55 9.12
7.76
6.44
5.19
20
P Active(MW)
70.71 70.72 70.73 70.73 70.73 70.73 70.74 70.74 70.76 70.75 70.75
P Reactive (MVAr)
44.25 42.34 40.42 38.5 36.57 34.62 32.68 30.72 28.76 26.79 24.82
Chaging Current (A) 55.629 55.65 55.68 55.7 55.73 55.76 55.78 55.8 55.84 55.86 55.89
Table 3. Behavior of power factor, voltage regulation, Active & reactive power, charging
current for series compensation of long transmission line
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First International Conference on Modern Communication & Computing Technologies (MCCT'14)
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Performance behavior of shunt compensation (only) of transmission line is executed for the improvement in transmission line attributes.
Calculated Values
Graph 4. Output Behavior of Different Parameter of Transmission Line with Series Compensation.
700
600
500
400
300
200
100
0
compensation factor -->
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
V_sending (kV)
150.79148.73146.73109.78101.94112.22 113.6 115.09136.18134.68133.23
I_sending (A)
553.22548.61544.01617.84623.35628.88 634.4 639.94 516.7 512.2 507.71
Power Factor
0.85 0.86 0.864 0.944 0.93 0.92410.9137 0.9 0.914 0.922 0.93
Efficiency %
94.27 95.45 96.63 104.17 103.2 102.22101.23100.24 103.6 104.77105.93
Power Increase % 100
110 123.6 139.98161.11189.21 227.9 282 361.19458.11 513
Table 4. performance behavior of Sending voltage, current, power factor, efficiency, power
increase for shunt compensation of long transmission line
The values given out for shunt compensation are visual showing the improvement
in power factor, efficiency, and load-ability of line. Physical location for estimating
the compensating equipment, the capacitors is installed in series in the transmission
line. Series compensation is especially important because large generating plants are
located hundreds of kilometer, from load center and large amount of power must be
transmitted in the entire region. Resulted efficient system will provide additional advantage.
Conclusion
This paper has presented the main results of some sensitive studies like by inserting the reactance in 220 kV transmission line through Matlab. Recent experiences at
National Transmission and Dispatch Company has shown that lower level of compensation in the entire electrical network can be successfully accomplished with shunt
and series reactance provided in cost effective manner and thereby maintain bulk
power transmission smart with Flexible AC Transmission Systems devices. It has
been analyzed that transmission lines may carry more power than rated set points.
Also the transmission parameters have diverse effect on overall performance of
transmission network. Simulation results of transmission line modeling provide favor
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First International Conference on Modern Communication & Computing Technologies (MCCT'14)
for improvement of sending end side. Comparison of values with all attributes; Pakistan is still lagging far behind by every technical and economic aspects to implement.
In that case smart grid technology can be a good choice. Because it is such a technology that once implemented then it will be very easy to maintain and operate the whole
system. As a result less amount of resource will be needed to operate the entire power
system of the country which will result a great amount of saving of both money and
man power. At the same time of the utilization of the available resources will be optimized to a great extent.
References
1. Farhangi, Hassan. "The path of the smart grid." Power and Energy Magazine, IEEE 8.1
(2010): 18-28.
2. Westermann, Dirk, and Antje Orths. "Smart Transmission—A first step towards an European overlay grid." Power and Energy Society General Meeting, 2012 IEEE. IEEE, 2012.
3. Karlsson, Daniel, Morten Hemmingsson, and Sture Lindahl. "Wide area system monitoring and control-terminology, phenomena, and solution implementation strategies." Power
and Energy Magazine, IEEE 2.5 (2004): 68-76.
4. Tate, Joseph Euzebe, and Thomas J. Overbye. "Line outage detection using phasor angle
measurements." Power Systems, IEEE Transactions on 23.4 (2008): 1644-1652.
5. Grainger, John J. Power system analysis. Tata McGraw-Hill Education, 2003.
6. Nguegan, Yves, A. Claudi, and Carsten Strunge. "Online monitoring of the electrical power transfer stability and voltage profile stability margins in electric power transmission systems using phasor measurement units data sets." Power and Energy Engineering Conference, 2009. APPEEC 2009. Asia-Pacific. IEEE, 2009.
7. Banirazi, Reza, and Edmond Jonckheere. "Geometry of power flow in negatively curved
power grid." Decision and Control (CDC), 2010 49th IEEE Conference on. IEEE, 2010.
8. Barooah, Prabir, and Joao P. Hespanha. "Graph effective resistance and distributed control:
Spectral properties and applications." Decision and control, 2006 45th IEEE conference
on. IEEE, 2006.
9. Demirci, T., et al. "Nationwide real-time monitoring system for electrical quantities and
power quality of the electricity transmission system." Generation, Transmission & Distribution, IET 5.5 (2011): 540-550.
10. Van Hertem, Dirk, and Mehrdad Ghandhari. "Multi-terminal VSC HVDC for the European supergrid: Obstacles." Renewable and sustainable energy reviews14.9 (2010): 31563163.
11. Westermann, Dirk, and Antje Orths. "Smart Transmission—A first step towards an European overlay grid." Power and Energy Society General Meeting, 2012 IEEE. IEEE, 2012.
12. Komoni, V., et al. "Control Active and Reactive Power Flow with UPFC connected in
Transmission Line." (2012): 31-31.
Biographies
Muhammad Usman Sardar is a IEEE fellow from 2009. He has received his B.Sc. Electrical Engineering degree (Hons.) from The Islamia University of Bahawalpur, Punjab, Pakistan
in 2012 and studying M.Sc. Engineering in major of Electrical Power Engineering from the
same Institute. Currently he is working as Lab Engineer in Electrical Power Engineering department of Swedish College of Engineering & Technology, Rahim Yar Khan, Punjab, Paki-
26-28 February, 2014, Nawabshah, Pakistan
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First International Conference on Modern Communication & Computing Technologies (MCCT'14)
stan. His areas of research interest are power transmission, Power system protection and Electrical Machines.
Mazhar Hussain Baloch He has received his B.E in Electrical Engineering from Mehran
UET, Jamshoro, Sindh, Pakistan in 2008 and received his M.E in Electrical Engineering from
Mehran UET, Jamshoro, Sindh, Pakistan in 2013, he has total 5years experience in different
fields, he has one research paper (National HEC recognized journals),at present he is working
as a Lecturer department of Electrical Engineering in Islamia University Bahawalpur, Punjab,
Pakistan. His research interest areas are in Energy and Management, Renewable Energy, Smart
Energy Systems, Transmission and Distribution, Protection System Schemes and Electrical
Machines.
Ghulam sarwar Kaloi. He has received his B.E in Electrical Engineering from Mehran
UET,Jamshoro,sindh Pakistan in 2006 and received his M.E in Electrical Engineering from
Quaid-e-awam UEST, Nawbshah, Sindh, Pakistan in 2013, he has total 4years experience in
different fields, ,at present he is working as a Lecturer department of Electrical Engineering in
Islamia University Bahawalpur, Punjab, Pakistan. His research interest areas are in electrical
power transmission & distribution, Electrical machines, Power system protection and renewable energy.
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