The popularity of distributed generation system is growing faster in the last few yearsrnbecause of their higher operating efficiency and low emission levels. Distributed generators makernuse of several micro-sources for their operation like photovoltaic cells, wind generator and fuelrncells. All the power generated by each is connected to a micro-grid for DG application. The microgridrnmustrnusernanrnelectricrninverterrnforrnpowerrnconditioningrnandrninterfacingrnwithrnthernpowerrnsystem.rnrnBasically,rnthernmicro-gridrninverterrnhasrntwornoperationrnmodes:rnStandalonernmodernandrnGrid-connectedrnrnmode.rnrnIn this thesis, the modeling of hybrid PV-Wind-FC distributed generation systems are done.rnDynamic models for the major system components, namely, wind, PV and fuel cell system modesrnare developed by using HOMER tool. The simulation and optimization is done based on climaticrndata sources and economics of the power components in which the Net Present Cost (NPC) has tornbe minimized to have economically feasible system. Moreover, other parameters like capacityrnshortage, renewable fraction, excess electricity and Cost of Energy (COE) are also considered torncheck the technical capability so as to select the best system. HOMER simulation result displaysrnthe most economical feasible system sorted by NPC from top to down, the prime system rankedrnfirst has renewable fraction of 15 unit wind turbines with 100kW each rating power, 1000kWrnphotovoltaic panel, 500kW fuel cell and 500kW converter are part of the system to fulfill thernrequired 1.3832MW estimated load demand. rnThen, a simulation model for the proposed hybrid power system is developed by usingrnMatlab/Simulink environment. This is done by creating a subsystem and masked block sets of rnthe major dynamic component models and then cascading in to a single aggregate model. rnThe final tasks are control system design and analysis of inverter interfaced micro-grid distributedrngenerations with existing utility- grid system. The analysis of controller is done using the MatlabrnM-file. For both operation modes, a multi-loop controller is used. The voltage differentialrnfeedback inner loop is embedded in the outer voltage loop also an output voltage decoupling andrncurrent decoupling are implemented by using the output voltage feedback. The proposed controlrnscheme possess very fast dynamic response at load step change and can also achieve good steadyrnstate performance at both linear and nonlinear loads.