Power Quality Improvement of Unbalanced Power System with
Distributed Generation Units
ABSTRACT:
This paper presents a power electronic system for improving
the power quality of the unbalanced distributed generation units in three-phase
four-wire system. In the system, small renewable power generation units, such
as small PV generator, small wind turbines may be configured as single phase
generation units. The random nature of renewable power sources may result in
significant unbalance in the power network and affect the power quality. An
electronic converter system is proposed to correct the system unbalance and harmonics
so as to deal with the power quality problems. The operation and control of the
converter are described. Simulation results have demonstrated that the system
can effectively correct the unbalance and enhance the system power quality.
KEYWORDS:
1.
Component
2.
Distributed generation
3.
Voltage source converter
4.
Power Quality Compensator
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig.1.
Instantaneous power relationship in a system and a parallel connected
compensator with energy storage system
Fig.2.The
connection of VSC in a three-phase four-wire system
EXPECTED SIMULATION RESULTS:
Fig.3.
Feeder 1 currents and power
Fig.4. Feeder 2 currents and
power
Fig.5. Grid currents and power
Fig.6.
Compensator currents and power
Fig.7.
Grid current fundamental component
CONCLUSION:
This
paper presents a study of using a voltage source converter (VSC) based
compensator to deal with the unbalance and harmonic distortion issue in the low
voltage system with embedded single phase DG units. The VSC performs the
functions of an interface for an energy storage system as well. The VSC is
connected in parallel with the system to control the energy storage system,
correct the system unbalance, remove the harmonic components and minimize the
neutral current of the supply system.
REFERENCES:
[1]
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[2]
M. Dussart, P. Lauwers, S. Magnus, Y. Laperches, “Connection requirements for
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standardization” Electricity Distribution, 2001. Part 1: Contributions.
CIRED2001, Conference Publication No. 482, © IEE2001
[3]
J.A.P. Lopes, “Integration of dispersed generation on distribution networks-impact
studies” Power Engineering Society Winter Meeting, 2002. IEEE, vol. 1, 2002,
pp. 323 –328.
[4]
F. Blaabjerg, Z. Chen, S. B Kjaer, “Power Electronics as Efficient Interface in
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vol. 19, Issue: 5, Sept. 2004, pp.1184- 1194.
[5]
Z. Chen, “Three Phase Four Wire System Power Redistribution Using A Power
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2000, pp. 47-49.
