ABSTRACT
Presently, the quality of power supplied is
essential to many customers. Power quality (PQ) is a valued utility service where
many customers are prepared to pay and get it. In the future, distribution
system operators ought to decide, to provide their customers with distinct PQ
ranges at different prices. Here, in this paper, a new control action to
improve and maintain and enhance the power quality of an electrical power
system is proposed in this paper. Fuzzy based distributed power flow controller
(DPFC) is designed and put into action to compensate the voltage imbalances
arising in a power system. This customized DPFC is an advanced FACTS device,
which has its structure analogous to unified power flow controller (UPFC). DPFC
comprises of both series and shunt converters, in which its three phase series
converter is distributed over the transmission line as several single phase
static converters ensuring high controllability and reliability at a low cost
compared to an UPFC. A central controlling circuit is designed to supply
reference signals to each of the individual controlling circuits of both series
and shunt converters. This customized device is applied to a single machine
infinite bus power system having nonlinear loads connected to it and is
simulated in MATLAB/Simulink environment by using OPAL-RT 5600 Real-time
digital Simulator. The results demonstrate the validation of proposed technique
to enhance the power quality.
KEYWORDS
1.
Power quality
2.
Voltage fluctuations
3.
Harmonic analysis
4.
Power harmonic filters
5.
Voltage control
6.
Load flow Voltage Sag and Swell
7.
Fuzzy Logic
SOFTWARE:
MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig.
1. Control network of DPFC
EXPECTED SIMULATION RESULTS
Fig.
2. Voltage waveform during fault condition
Fig.
3. Current waveform during fault condition
Fig.
4. Simulated results for Voltage by employing DPFC controller
Fig.
5. Simulated results for Current by employing DPFC controller
Fig.
6. THD of load voltage without Controller
Fig.
7. FFT Analysis for PI Controller
Fig.
8. FFT Analysis for Fuzzy Controller
CONCLUSION
The
work is presented to provide a solution for maintaining Power Quality at the
distribution end, compensation of harmonics in grid voltage and in load
currents. In order to consummate specified intentions in this paper a new
concept for controlling power quality problems was proposed and implemented. By
putting the customized device into action, results were analyzed for voltage
dips and their mitigations for a three phase source with non-linear loads. The
DPFC is modeled by positioning three control circuits designed independently.
In this paper we also proposed and implemented the concept of fuzzy logic
controller for having better controlling action, which will help in minimization/elimination
of harmonics in the system. As compared to all other facts devices the Fuzzy
based DPFC converter effectively controls all power quality problems and with
this technique we can put THD to 3.04% proving the effectiveness of the
proposed controller.
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