ABSTRACT:
Flexible
AC transmission system (FACTS) is a technology, which is based on power
electronic
devices, used to enhance the existing transmission
capabilities in order to make the transmission system flexible and independent
operation. The FACTS technology is a promising technology to achieve complete
deregulation of Power System i.e. Generation, Transmission and Distribution as
complete individual units. The loading capability of transmission system can
also be enhanced nearer to the thermal limits without affecting the stability.
Complete close-loop smooth control of reactive power can be achieved using
shunt connected FACTS devices. Static VAR Compensator (SVC) is one of the shunt
connected FACTS device, which can be utilized for the purpose of reactive power
compensation.. This paper attempts to design and simulate the Fuzzy logic control
of firing angle for SVC (TCR & FC-TCR) in order to achieve better, smooth
and adaptive control of reactive power. The design, modeling and simulations
are carried out for λ /8 Transmission line and the compensation is placed at
the receiving end (load end). The results of both SVC (TCR & FC-TCR)
devices
KEYWORDS:
1. Fuzzy Logic
2. FACTS and SVC
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig.1.
Single Phase equivalent circuit and fuzzy logic control structure of SVC
EXPECTED SIMULATION RESULTS:
Fig.2.
Uncompensated voltages for R=500 Ω
Fig.3.
Compensated voltages for R=500 Ω with TCR
Fig.4.
Compensated voltages for R=500 Ω with FC-TCR
Fig.5.
Active and Reactive powers of the Tr.line R=200 Ω after compensation with
FC-TCR
Fig.6.
Active and Reactive powers of the Tr.line for R=200 Ω after compensation with
TCR
CONCLUSION:
This
paper presents an “online Fuzzy control scheme for SVC” and it can be concluded
that the use of fuzzy controlled SVC (TCR & FC-TCR) compensating devices
with the firing angle control is continuous, effective and it is a simplest way
of controlling the reactive power of transmission line. It is observed that SVC
devices were able to compensate over voltages. Compensating voltages are shown
in Fig.15 and Fig.16. The use of fuzzy logic has facilitated the closed loop
control of system, by designing a set of rules, which decides the firing angle
given to SVC to attain the required voltage. The active and reactive power
compensation with SVC devices was shown in Fig.17 and Fig.18. With MATLAB
simulations [4] [5] and actual testing it is observed that SVC (TCR &
FC-TCR) provides an effective reactive power control irrespective of load
variations.
REFERENCES:
[1]
Narain. G. Hingorani, “Understanding FACTS, Concepts and Technology Of flexible
AC Transmission Systems”, by IEEE Press
USA
[2]
Bart Kosko, “Neural Networks and Fuzzy Systems A Dynamical Systems Approach to
Machine Intelligence”, Prentice-Hall of India New Delhi, June 1994.
[3]
Timothy J Ross, “Fuzzy Logic with Engineering Applications”, McGraw-Hill, Inc,
New York, 1997.
[4]
Laboratory Manual for Transmission line and fuzzy Trainer Kit Of Electrical
Engineering Department NIT Warangal
[5]
SIM Power System User Guide Version 4 MATLAB Manual Periodicals and Conference
Proceedings:
