This book presents the control strategies for fuel cell and solar cell in conjunction of DC-DC converter. The growing demand for renewable energy sources has promoted research in this area . This book presents i) Power conditioning unit of fuel cell with DC-DC converter ( Boost and Buck Converter). ii) Solar cell in conjunction of DC-DC converter with different MPPT tracking methods like perturb and observe, incremental conductance etc with an aim to help PG students to understand modeling and design using SIMULINK.