ABSTRACT:
In
this work, a novel technique based on adaptive filtering is proposed for the
control of three phase universal active power filter with a solar photovoltaic
array integrated at its DC bus. Two adaptive filters along with a zero crossing
detection technique, are used to extract the magnitude of fundamental active
component of distorted load currents, which is then used in estimation of
reference signal for the shunt active filter. This technique enables extraction
of active component of all three phases with reduced mathematical computation.
The series active filter control is based on synchronous reference frame theory
and it regulates load voltage and maintains it in-phase with voltage at point
of common coupling under conditions of voltage sag and swell. The performance
of the system is evaluated on an experimental prototype in the laboratory under
various dynamic conditions such as sag and swell in voltage at point of common
coupling, load unbalancing and change in solar irradiation intensity.
KEYWORDS:
1. Power
quality
2. Universal
active power filter
3. Adaptive
filtering
4. Photovoltaic
system
5. Maximum
power point tracking
6. Quadrature
signal generation
SOFTWARE:
MATLAB/SIMULINK
The
performance of adaptive filter based PV-UAPF system under both steady state and
dynamic conditions, have been analyzed in detail. The method of sampling the
fundamental component of load current obtained through adaptive filter enables
fast extraction of fundamental active component of nonlinear load currents for
all phases in one sampling. Only two adaptive filters are required to extract
magnitude of active component of three phase load currents. This technique
requires reduced computational resources while achieving good dynamic and
steady state performance in extraction of fundamental active component of
nonlinear load current. The system performance has been found to be
satisfactory under various disturbances in load current, PCC voltage and solar
irradiation. The series active filter is able to regulate load voltage at 220 V
under variations of PCC voltage from 170 V to 270 V. The grid current THD is
maintained at approximately 3% even though the THD of load current is 28% thus
meeting requirement of IEEE-519 standard. The PV-UAPF system has been able to maintain
the grid currents balanced under unbalanced loading condition.
The
proposed topology and algorithm are suited for employing in conditions where
PCC voltage sags/swells and load current harmonics are major power quality
issues. Certain power quality issues not addressed include voltage distortions,
flicker, neutral current compensation etc. This power quality issues can be
addressed by modification of topology and control algorithm according to the
requirements in the distribution system. The PV-UAPF system provides dual
benefit of distributed generation as well as improving power quality of the
distribution system.
REFERENCES:
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[2]
B. Singh, A. Chandra, K. A. Haddad, Power Quality: Problems and Mitigation
Techniques. London: Wiley, 2015.
[3]
S. Devassy and B. Singh, “Control of solar photovoltaic integrated upqc operating
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pp. 1413–1421, Oct 2017.
[4]
S. Devassy and B. Singh, “Performance analysis of proportional resonant and
adaline-based solar photovoltaic-integrated unified active power filter,” IET
Renewable Power Generation, vol. 11, no. 11, pp. 1382– 1391, 2017.
[5]
L. Ramya and J. Pratheebha, “A novel control technique of solar farm inverter
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