Smart Controller for Solar Roof Top

Abstract

In the present scenario, the snowballing demand of the electricity has led to great need of power from the renewable energy sources i.e. wind and solar. Additionally, the fossil fuel assets are reducing at very high rate such that they can become obsolete anytime. Hence in country like India where solar energy is widely available throughout the year. In current financial year, the solar power generation reached to its peak and expected to grow more rapidly due to encouragement provided to it by the present government. Nowadays a new concept has been introduced where every building whether home, industry, institution or commercial institution can generate solar power by installing PV panels on the roof top. The generated power can be utilized by the proprietor and the additional power can be fed back to grid and power supplier agency pays for the power fed into the grid. Additionally such solar grid tied inverters eliminates the requirement of stepping up the inverter output voltage to high voltage level. This ultimately results into cost reduction and ease of implementation. Hence smaller PV rooftop systems of 10-500 kW which can be connected to grid at the lower voltage levels like 230 V or 415 V has come into trend recently. This project presents the solar grid tied inverter including maximum power point tracking (MPPT), different PWM Techniques and PLL for the grid tied inverter. For the grid synchronization various methods has been suggested. Among them PLL using second order generalized integration (SOGI) method was tested. While development in depth study for the output filter has been carried out. Further, the optimal design of LCL filter for grid connected inverter system is studied. The complete model of the study is simulated in Matlab™simulink environment for practicability of the study. For the hardware implementation, DSP TMS320F28335 was utilized to develop algorithms and generating desired response.