ABSTRACT:
The
study proposes a method to optimize dc-link voltage of Distribution Static
Compensator (DSTATCOM) based on load compensation requirement using Reduced
Switch Count Multi-Level Converter (RSC-MLC) integrated with Photo-Voltaic (PV)
system. The proposed method is capable of compensating reactive power,
unbalance and harmonics demanded by three phase unbalanced and non-linear loads
connected to the distribution side, leading to improvement of power quality. It
is also capable of providing real power support to the load and thus prevents
source from getting over loaded whenever required. During off-peak loads, the
dc-link voltage can be brought down to a lower value, which will reduce the
voltage-stress across switches of inverter and minimizes the switching losses.
The variation of dc-link voltage is provided using RSC-MLC which requires dc
voltage supply. This method utilizes renewable resources of energy such as
solar cells as the dc voltage source. The output voltage of PV panel is boosted
to a higher value using High Gain Boost Converter (HGBC) and given to RSC-MLC.
The maximum power point tracking (MPPT) of PV panels is achieved by using Perturb
and Observe (P & O) algorithm. The results have been verified through
simulation and experimental studies.
KEYWORDS:
1. DC-link
voltage
2. DSTATCOM
3. Power
Quality
4. PV
system
5. Reduced
Switch Count Multi Level Converter (RSCMLC)
6. Switching
Losses
SOFTWARE:
MATLAB/SIMULINK
CONCLUSION:
A
new method is proposed to regulate the dc-link voltage using RSC-MLC without
affecting the performance of DSTATCOM. It also uses renewable energy resources
for obtaining dc voltage source such as PV panels, Fuel cells. Using PV panels
effectively enables it to deliver real power as well as compensation to the
load during day time and work purely as DSTATCOM for power quality improvement at
night. It can be observed from simulation and experimental results that
compensation for reactive power and harmonics has been achieved effectively.
The source current is balanced, sinusoidal, distortion-free and with improved
power factor. The %THD has reduced significantly after compensation. Also, due
to reduced dc-link voltage at lesser loads, voltage stress across the switches
has reduced and switching losses are minimized to a great extent, increasing
the life-time and efficiency of DSTATCOM. Hence, it can be a good alternative for
power quality improvement and real power support to the load.
REFERENCES:
[1]
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[2]
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[3]
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[4]
B. Singh, S. R. Arya, C. Jain, S. Goel, “Implementation of Four-leg Distribution
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[5]
R. P. Tondare, S. P. Gawande, M. R. Ramteke, “Modeling of Split Capacitor Based
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Computing Applications (C2SPCA), Bangalore, pp. 1-6, 2013.
