Design of Control Unit for Off-grid and Grid Connected Solar- Wind Hybrid System Suitable for Supplying Power to both AC and DC Loads

There are two types of solar-wind hybrid system available in the market; off-grid and grid connected system. Off-grid system supplies power to the local load while grid connected system export power to the grid. To meet the ever-increasing energy demand and also to take an advantage of reduced energy generation cost through renewable energy sources, people are showing interest to have Solar PV and Solar- Wind hybrid system on their premises. It has been observed that both AC and DC loads are now a days common among domestic energy users. The excess energy generated from higher capacity hybrid system after meeting the local AC/DC loads gets exported to the grid. There is a need for developing suitable converter, inverter and control units with further advancements in the power electronics components which can supply power to both AC and DC loads as well as can export power to the grid. In the present work, a control unit was designed for a solar-wind hybrid system based on MATLAB simulation analysis which can supply power to the local AC/DC loads as well as export power to the grid. It has been found that the developed system is able to produce 230V AC pure sinusoidal wave as output. For supplying power to the local DC loads, a suitable converter was designed to provide DC output voltage at the desired level. A suitable synchronization unit was used before exporting power to the grid for bringing the frequency variations, voltage and current harmonics within the acceptable range as per the standards IEC 61727, IEEE 1547 and IEEE 929.