ABSTRACT
According to growth of electricity demand and the increased
number of non-linear loads in power grids, providing a high quality electrical
power should be considered. In this paper, Enhancement of power quality by
using fuzzy based multilevel power flow controller (DPFC) is proposed. The DPFC
is a new FACTS device, which its structure is similar to unified power flow
controller (UPFC). In spite of UPFC, in DPFC the common dc-link between the
shunt and series converters is eliminated and three-phase series converter is
divided to several single-phase series distributed converters through the line.
This eventually enables the DPFC to fully control all power system parameters. It,
also, increases the reliability of the device and reduces its cost simultaneously.
In recent years multi level inverters are used high power and high voltage
applications .Multilevel inverter output voltage produce a staircase output
waveform, this waveform look like a sinusoidal waveform leads to reduction in
Harmonics. Fuzzy Logic is used for optimal designing of controller parameters.
Application of Fuzzy Multilevel DPFC for reduction of Total Harmonic Distortion
was presented. The simulation results show the improvement of power quality
using DPFC with Fuzzy logic controller.
KEYWORDS:
1.
FACTS
2.
Power Quality
3.
Multi Level Inverters
4.
Fuzzy Logic
5.
Distributed Power Flow
Controller component
SOFTWARE: MATLAB/SIMULINK
BLOCK
DIAGRAM:
Fig.1: The DPFC Structure
EXPECTED SIMULATION RESULTS:
Fig.2:
5 Level Voltage Waveform
Fig.3:
Three Phase output Voltage and Current Waveform
Fig.4:
Supply Voltage and Current Waveform with unity PF
Fig.5:
THD with out fuzzy
Fig.6:
THD with fuzzy
CONCLUSION
In
this paper Fuzzy Logic Controller technique based distributed power flow
controller (DPFC) with multilevel voltage source converter (VSC) is proposed.
The presented DPFC control system can regulate active and reactive power flow
of the transmission line. We are reducing the THD value from 24.84% to 0.41% by
using this technic as shown in fig’s (12) & (13).The series converter of
the DPFC employs the DFACTS concept, which uses multiple converters instead of one
large-size converter. The reliability of the DPFC is greatly increased because
of the redundancy of the series converters. The total cost of the DPFC is also
much lower than the UPFC, because no high-voltage isolation is required at the
series converter part and the rating of the components are low. Also results
show the valid improvement in Power Quality using Fuzzy Logic based Multilevel
DPFC.
REFERENCES
[1] K
Chandrasekaran, P A Vengkatachalam, Mohd Noh Karsiti and K S Rama Rao, “Mitigation
of Power Quality Disturbances”, Journal of Theoretical and Applied Information
Technology, Vol.8, No.2, pp.105- 116, 2009
[2] Priyanka Chhabra, “Study of Different Methods
for Enhancing Power Quality Problems”, International Journal of Current Engineering
and Technology, Vol.3, No.2, pp.403-410, 2013
[3] Bindeshwar Singh, Indresh Yadav and Dilip
Kumar, “Mitigation of Power Quality Problems Using FACTS Controllers in an
Integrated Power System Environment: A Comprehensive Survey”, International Journal
of Computer Science and Artificial Intelligence, Vol.1, No.1, pp.1-12, 2011
[4] Ganesh Prasad Reddy and K Ramesh Reddy, “Power
Quality Improvement Using Neural Network Controller Based Cascaded HBridge Multilevel
Inverter Type D-STATCOM”, International Conference on Computer Communication
and Informatics, 2012
[5] Lin
Xu and Yang Han, “Effective Controller Design for the Cascaded Hbridge Multilevel
DSTATCOM for Reactive Compensation in Distribution Utilities”, Elektrotehniski
Vestnik, Vol.78, No.4, pp.229- 235, 2011
