The quest to reduce greenhouse gasses and increase in global electric power generation leads to the increasing deployment of distributed generations (DGs) through the exploration of the renewable energy sources (RES) for electrical power generation. These DGs are seen with the rise in the deployment of the solar and wind energy based microgrids as well as distributed synchronous generators, whose operation can be autonomous or grid connected. As a result, the so-called conventional power systems now evolve into modern power systems as they become characterized by increase in the integration of these DGs. As these RES are interfaced with inverters which have low inertia, their combination with the synchronous generators poses new stability challenges. Hence, my research focus is on how to investigate the stability of these evolving power systems through the application of appropriate advance nonlinear control tools.