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 without 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