1) The document discusses using boost converters to increase the output of solar panels. It proposes using a microcontroller to obtain a duty cycle of up to 0.5 to improve efficacy with a ferrite-core inductor. 2) The proposed design uses a single pole double throw relay connected to a comparator to switch the load between the boost converter output and main supply if solar output is insufficient. 3) Applications discussed include use in hybrid electric vehicles to boost battery voltage and use in solar home lighting systems to boost solar cell output to a high enough voltage to power lamps.

1. Increasing output of Solar Panel using
Boost Converters
Aditi, Arnav Gupta, Himanshu Lohani
Electrical and Electronics Engineering , Krishna Institute of Engineering and Technology, Uttar Pradesh Technical University
Introduction
• Alternative energy sources are inherently non-polluting and
continuous free in their availability, . However, their applications
in conventional distribution systems are limited due to high
initial cost and reliability issues.
• It is anticipated that PV systems will become one of the main
energy resources to full fill the global energy requirement by the
end of this century
• The daily average solar energy incident over India varies from 4
to 7 kWh/m2 with about 1500–2000 sunshine hours per year
(depending upon location), which is far more than current total
energy consumption
• Assuming the efficiency of PV modules were as low as 10%, this
would still be a thousand times greater than the domestic
electricity demand projected for 2015. the cost of generating
solar power.
Hypothesis
• The boost converter has the reputation of being low-
performance and complicated to design
• Operating in DCM generally will result in a higher loop
bandwidth at the expense of lower efficiency. The DCM
converter will likely be smaller due to the smaller inductor, but
the demands on the output capacitor’s ability to handle ripple
current are higher.
• In this project we are using a ferric –core inductor in which
frequency cannot be increased much since that will lead to
losses hence to improve the efficacy a microcontroller can be
used to obtain a duty cycle of up to 0.5.
Project approach
• The design of the model has been made by giving the running
condition of the load the utmost importance.
• In case of poor sunlight if the output of the of the PV panel is
not enough to drive the boost converter components so that
the converter could boost the voltage to drive the load, then
the load will be switched over to the main supply so that the
load gets uninterrupted power supply.
• To do this a single pole double throw (SPDT) relay has been
used which can connect the load to any one of the inputs i.e
the main supply or the boost converter output.
• The SPDT gets it commands of switching between the two
inputs through the comparator which compares the output
voltage of the PV panel with the test voltage taken from the
battery.
• If the output of the comparator is positive then the SPDT puts
the load on the boost converter and if the output of the
comparator is negative then the SPDT puts the load on the
main supply.
Figure 2 Block Diagram
Applications
•Hybrid Electric Vehicles
The NHW20 model Toyota Prius HEV uses a 500 V motor. Without a
boost converter, the Prius would need nearly 417 cells to power the
motor. However, a Prius actually uses only 168 cells and boosts the
battery voltage from 202 V to 500 V.
•Solar Home Lighting System
The electric output of solar cells which is typically of the order of
0.5 Volt cannot directly be used for large lighting systems.
Therefore, DC-DC boost converter is used to boost this voltage to
12-24 V for the purpose of lighting street lamps, i.e., halogen bulbs.
Concluding Remarks
This project uses the DC-DC Boost converter to boost the solar
panel output to efficient levels and support the load. If the
required voltage from the solar-panel drops below the test
voltage then the relay switches load to the mains. However
output voltage and load current always depend upon the
application
References
• C. K. Tse and K. M. Adams, "Qualitative analysis and control
of a DC-to-DC Boost Converter Operating in Discontinuous
Mode", IEEE Transactions on Power Electronics, Vol. 5, No.
3, July 1999, Pp 323-330.
• Diary R. Sulaiman, Hilmi F. Amin, and Ismail K. Said.,
“Design of High Efficiency DCDC Converter for Photovoltaic
Solar Home applications”, Journal of Energy and Power
engineering, 2009.
Figure 1 DC DC Boost Converter