ABSTRACT:
Steady
state and transient problems in a power system have undesirable consequences on
the system. It can limit the amount of power that can be transmitted in the
system and consequently leads to voltage instability and at times it may also
result into total voltage collapse.The main objective of this paper is a
comparative investigate in enhancement of volatge stability via static
synchronous series compensator (SSSC) and static var compensator (SVC)
externally controlled by a POD controller. The new designed P.O.D
controller is very efficient for voltage stability under transient conditions.
This paper discusses and demonstrates the comparision between the SVC with
P.O.D controller and SSSC with P.O.D controller,applied to power system for
effectively regulating system voltage for different types of faulted condition.
One of the major reasons for installing a SVC is to improve dynamic voltage
control and thus increase system load ability during transient condition. This
work is presented to present the transmission line voltage stability &
machine oscillation damping stability by using SVC & SSSC with POD
controller & compared their performance to enhance the stability of a power
system. Simulation results shows that SVC with POD controller is more effective
to enhance the voltage stability and increase transmission capacity in a power
system.
KEYWORDS:
1.
FACTS
2.
Power system
3.
POD Controller
4.
SVC(Static
VAR compensator)
5.
SSSC(static
synchronous series compensator)
6.
Voltage
Stability.
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig.1
Single line diagram of a 2-machine power system
SIMULATION DIAGRAM:
Fig.
2 Simulation Diagram of the SSSC
Fig.
3 Simulation Diagram of SVC Controller
EXPECTED SIMULATION RESULTS:
Fig.
4(a) Simulation Results of SSSC without POD
Fig.
4(b) Simulation Results of SSSC without POD
Fig.
5(a) Simulation Results of SSSC with POD
Fig.
5(b) Simulation Results of SSSC with POD
Fig.
6 Simulation results of SVC Controller
Fig. 7(a) Bus voltages in p.u for 1-phase fault (without SVC)
Fig. 7(b) Bus Voltages in p.u for 1-phase fault (with SVC)
CONCLUSION:
This
paper explains, the FACTS controllers that are used to mitigate the power
quality problems. The standard FACTS controller for a particular type of
problem is also given. The simulation results give the clear observation of how
the FACTS devices improve the power quality. The simulation work is done on
Static Var Compensator (SVC) and Static Synchronous Series
Compensator(SSSC).SVC and SSSC are providing better power quality under
variation of source voltage and when the system is suddenly loaded. The thesis
includes the simulation results of the SVC and SSSC only. The future work given
as the simulation results of the systems for various power quality problems
with all remaining FACTS devices. Then it can be very easy to find an exact
FACTS device for a particular type of power quality problem. Installations of
SSSC and SVC controllers at all suitable locations will naturally improve the
voltage stability of a power system. But, keeping in mind, the cost of the
controllers and the optimization task, the number of controllers and their
sizes are minimized. Taking corrective actions to keep the system voltage
secured under all possible line outage contingency will not be economical or it
may not be necessary. Therefore, only the most critical line outage contingency
is considered. The line outage is ranked according to the severity and the
severity is taken on the basis of increased reactive power generation and real
power losses. Outage of other lines has no much impact on the system and
therefore they are not given importance.
REFERENCES:
[1]
Molina, M.G. and P. E. Mercado, “Modeling of a Static Synchronous Compensator
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[2] Molina, M.G. and P. E. Mercado, “New
Energy Storage Devices for Applications on Frequency Control of the Power
System using FACTS Controllers,” Proc. X ERLAC, Iguazú, Argentina, 14.6, 2003,
1-6.
[3] Molina, M.G. and P. E. Mercado,
“Evaluation of Energy Storage Systems for application in the Frequency
Control”, Proc. 6th COBEP, Florianópolis, Brazil, 2001, pp. 479-484.
[4]
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