Author : Varaprasad N. L., P. M. Krishna, S. Rajanna, Mohanalakshmi J., Shruthi K and T. S. Shruthi

Photovoltaic (PV) energy conversion is now recognized to be the most widely accepted method of harnessing renewable energy sources to benefit communities, especially in developing countries. PV arrays provide direct conversion of solar energy into electrical energy without inducing environmental pollution. Recognizing these facts, extensive research and development efforts are devoted to photovoltaic. Especially in countries like India where the government is facing oil crunch, the tapping of PV energy which is available in abundance throughout the year is considered to be very important. The main encumbrance for the reach of PV systems is their low efficiency and high capital cost. The present work, intends to examine a schematic to draw out maximum obtainable solar power from a PV system to be used in DC application. The concept of Maximum Power Point Tracking (MPPT) is implemented by using Fuzzy Logic, which results in appreciable increase in the voltage level required. The MPPT algorithm thus proposed will identify the suitable duty ratio in which the DC/DC converter should be operated to obtain maximum power output. The obtained maximum power can be used to charge the battery, as well as to run the DC motor. The proposed scheme also focuses in developing a microcontroller based closed loop scheme for the speed control of a DC motor fed from PV array. The microcontroller keeps on tracking the determined speed by varying duty cycle in a closed loop control system.

Keywords: DC/DC converter, MPPT, PV system, Fuzzy logic control, Microcontroller, DC motor.

Article published in International Journal of Current  Engineering  and Technology, Vol.3,No.4(Oct- 2013)