ABSTRACT:
This paper presents the detailed design and modeling
of grid integrated with the Photovoltaic Solar Power Generator. As the
Photovoltaic System uses the solar energy as one of the renewable energies for
the electrical energy production has an enormous potential. The PV system is
developing very rapidly as compared to its counterparts of the renewable
energies. The DC voltage generated by the PV system is boosted by the DC-DC Boost
converter. The utility grid is incorporated with the PV Solar Power Generator
through the 3-ı PWM DC-AC
inverter, whose control is provided by a constant current controller. This controller
uses a 3-ı phase locked loop
(PLL) for tracking the phase angle of the utility grid and reacts fast enough
to the changes in load or grid connection states, as a result, it seems to be
efficient in supplying to load the constant voltage without phase jump. The
complete mathematical model for the grid connected PV system is developed and
simulated. The results verify that the proposed system is proficient to supply
the local loads.
KEYWORDS:
1.
PV Solar Power Generator
2.
DC-DC Boost Converter
3.
PWM inverter
4.
PLL
5.
Constant Current Controller (CCC)
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig.1
Switching Model of Solar Inverter
EXPECTED SIMULATION RESULTS:
Fig.2
P-V Curve of the Solar Array
Fig.
3 V-I Curve of the Solar Array
Fig.
4 DC voltage delivered by the Boost converter
Fig.
5Inverter output voltage before filtering
Fig.
6 Inverter output voltage after filtering
Fig.
7 Load current for supplying the 2 MW load.
Fig.8
Load current for supplying the load of about 30 MW, 2 MVAr
CONCLUSION:
For
improving the energy efficiency and power quality issues with the increment of
the world energy demand, the power generation using the renewable energy source
is the only solution. There are several countries located in the tropical and
temperature regions, where the direct solar density may reach up to 1000W/m2.
Hence PV system is considered as a primary resource. In this paper, the
detailed modeling of grid connected PV generation system is developed. The
DC-DC boost converter is used to optimize the PV array output with the closed
loop control for keeping the DC bus voltage to be constant. The 2 level 3-phase
inverter is converting the DC into the sinusoidal AC voltage. The control of
the solar inverter is provided through the constant current controller. This
controller tracks the phase and frequency of the utility grid voltage using the
Phase- Locked-Loop (PLL) system and generates the switching pulses for the
solar inverter. Using this controller the output voltage of the solar inverter
and the grid voltage are in phase. Thus the PV system can be integrated to the
grid. The simulation results the presented in this paper to validate the grid
connected PV system model and the applied control scheme.
REFERENCES:
[1]
A. M. Hava, T. A. Lipo and W. L. Erdman. “Utility interface issues for line
connected PWM voltage source converters: a comparative study”, Proceeding of
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[2]
L. J. BORLE, M. S. DYMOND and C. V. NAYAR, “Development and testing of a 20 kW
grid interactive photovoltaic power conditioning system in Western Australia”,
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[3]
M. Calais, J. Myrzik, T. Spooner, V. Agelidis, “Inverters for single- phase grid
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Electronics Specialists Conference, Volume 4, 23-27 June 2002
[4]
S. K. Chung, “Phase-Locked Loop for Grid connected Three-phase Power Conversion
Systems”, IEE Proceeding on Electronic Power Application, Vol. 147, No. 3, pp.
213-219, 2000.
[5]
S. Rahman, “Going green: the growth of renewable energy”, IEEE Power and Energy
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