Voltage Source Converters (VSCs) have been widely used in renewable energy, distributed power generation and microgrid applications. VSCs can not only control the power transfer among the sources, grid and loads but also make it possible to improve the power quality via the converter control. At PEMSES, we investigate the interfacing VSC control methods that can effectively share the active/reactive load power demand in islanded microgrid as well as actively mitigate the LCL filter resonance and harmonics caused by non-linear loads in grid-connected microgrid system. A 5kW experimental prototype comprises IGBT-based three phase VSC, dSPACE MicroLab Rapid Control Prototyping (RCP) controller and Chroma Regenerative Grid Simulator is developed to verify the ideas.