ABSTRACT:
The
paper
presents design of hybrid active power filter (HAPF) in a three-phase
three-wire power system. Design is implemented with instantaneous reactive power
theory for control of HAPF in order to mitigate harmonics generated by both
non-linear and unbalanced load at the point of common coupling (peC). The p-q
Theory enables the source current to be decomposed in αβ0 frame to obtain
compensation current for each phase. The hysteresis band current controller is
used to generate gating pulses for voltage source inverter (VSI). Over all
harmonic reduction is achieved via the proposed control of HAPF and the THD levels
are per the IEEE-519 standard. Investigation of proposed scheme is validated by
extensive simulations using MATLAB / Simulink Sim-Power System tool box.
KEYWORDS:
1.
Harmonics
2.
Passive
Filter
3.
Active Filter
4.
Hybrid Filter
5.
Power Quality
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig. 1: Basic Diagram of SAF
EXPECTED SIMULATION RESULTS:
Fig. 2: Source Current THD (29.9%)
without Filter
Fig. 3: Source Current THD (10. I
5%) using Passive Filter
Fig.
4: Source Current THD (4.47%) using Active Filter
Fig.
5: Source Current THD (2.02%) using HAPF
Fig.
6: Compensating Current for Phase a,b and c
Fig.
7: Load Current THD (10.39%) in HAPF
CONCLUSION
This
paper highlights the efficacy of HAPF for improving the power quality by
eliminating harmonics from power system. The HAPF with a constant power compensation
control strategy and hysteresis-band current controller is proposed. A thorough
simulation based investigation validates the competency of HAPF among all
filters for harmonic mitigation in power system due to current quality problem.
The performance examined has demonstrated the efficiency by reducing the source
current THD for non-linear load. The THD is well below the specified limit
ofIEEE-519 standard.
REFERENCES
[1]
A. Baitha and N. Gupta, " A comparative analysis of passive filters for
power quality improvement", Int. Conf on Advancements in Power and Energy
(TAP Energy), pp. 327-332, 20 IS .
[2]
B. Singh and V. Verma, "An improved hybrid filter for compensation of
current and voltage harmonics for varying rectifier loads". Int. J.
Electrical Power & Energy Systems, Vol. 29, No. 4, pp. 312-xxx, May 2007.
[3]
H. Fujita, T. Yamasaki, and H. Akagi, " A hybrid active filters for damping
of harmonic resonance in industrial power system," IEEE Trans. on Power
Electrics, Vol IS , No. 2, pp. 209-216, 2000.
[4]
F.Z. Peng, H. Akagi, and A. Nanbe, " A new approach to harmonic compensation
in power systems-A combined system of shunt passive and series active
filters," I EEE Trans. on Ind. Appt, Vol. 26, pp. 983-990, Nov. 1990
[5]
B. Singh and V. Verma, "Design and Implementation of a Current Controlled
Parallel Hybrid Power Filter" Int. Conf on Power Electronics, Drives and
Energy Systems, PEDES'06, pp. 1-7, 2006.
