Renewable energy-based electric power generation is receiving more attention due to the increasing power demand and environmental concerns. The interconnection of these distributed resources to the grid is based on the grid code standards to ensure power quality, reliability, and security. The intermittent nature of the renewable penetrated grid, along with phasing out of conventional generation units, new HVDC lines, and long-distance transmissions from remote areas, impose several challenges to grid stability. Hence it is crucial to explore control approaches that can efficiently control these Distributed Energy Resources (DERs) to improve the overall power quality and reliability. This dissertation presents modeling, stability studies, and advanced control architectures that can support and coordinate the Wind Energy Conversion Systems (WECS) and other inverter-based Distributed Energy Resources (DERs) to improve the quality of the generation, transmission, and distribution systems. The first part of the work proposes advanced adaptive-based robust sensorless control approaches for rotor side and grid side control of DFIG based WECS.Further, the dissertation discusses the challenges of transferring high power of renewable penetrated grid and some possible solutions and control approaches. Finally, the work efficiently coordinates the available resources to ensure power quality in a distribution network. All the proposed designs are validated using simulation results developed by dynamic models or through real-time simulators, which proves the ability of the advanced controllers to improve grid reliability. The quantification based on standard metrics used for performance improvements discussed in each design shows that the designs have exceptional advantages compared with conventional controllers.