ABSTRACT:
This paper presents a new idea to
benefit of eliminated harmonics current by using a new topology of hybrid
active power filter (HAPF) to compensate harmonics current to be sinusoidal in
order to feed some loads. The design and simulation of a new three phase HAPF
circuit using a shunt active power filter (APF) connected in parallel with a
capacitor (C) line of a (LC) low pass filter (LPF) has been submitted.
The first aim of the new circuit is to
use the LPF as a path to pass the fundamental frequency (50 Hz) current and
eliminate other high order frequencies, while APF compensates high order
frequencies and compensate reactive power of the circuit. The second aim is to
benefit from the modified wave in the high frequency branch of LPF to use it as
a useful power in order to feed different loads. In addition, With this
topology, the resonance problem (which usually happens between LPF and the system)
will disappear because of using of APF in the high frequency branch.
The control circuit has been designed
based on the instantaneous reactive power theory. A Clarke transformation
equations and hysteresis current controller have been used in the HAPF’s
design. The proposed circuit has provided a good harmonic elimination, total harmonic
distortion (THD) reduced, reactive power compensation and a reasonable
sinusoidal waveform.
KEYWORDS:
1.
Harmonics Elimination
2.
Hybrid Active Power Filter
3.
Active Power Filter
4.
Passive Filters
5.
Total Harmonic Distortion
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig.
1. New proposed HAPF
EXPECTED SIMULATION RESULTS:
Fig.
2. C-branch’s current before adding APF
Fig.
3. Source current before filtering
Fig.
4. Source current after filtering
Fig.
5. The current of resistive load after filtering
CONCLUSION:
This paper has presents a new topology
of three phase HAPF. The system has been designed, tested and simulated by
Matlab- Simulink program in three steps; firstly, without using filters, secondly,
with LC low pass filter, finally, using LPF in combine with APF which represent
HAPF. After a comparison between the values of total harmonic distortion (THD%)
in three aforementioned circuits, the results of the simulation confirmed the effectiveness
of the proposed HAPF because of the big decreasing in the THD value and high
rate elimination of the harmonics. The proposed HAPF offers a reactive power
compensation for the circuit because of using shunt APF. Consequently, the
power quality of the circuit will improve. This paper has submit a new idea to
benefit of eliminated harmonic current in the C-branch of LPF through using APF
in shunt with C-branch of LPF and compensate high frequency currents in order
to use it as a power supply to feed different loads. In this research, a
resistive load has been presented as an invested load. However, in practical
life lighting bulbs can be used as loads.
REFERENCES:
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