摘要：In recent years the electric energy sector has been experiencing an extension into distributed generation, and in this context microgrids have been achieving increasing importance. Microgrids are composed of renewable and conventional generation systems, storage and distributed loads that working under a system control that could be operated in grid connected or islanded mode. However, the increasing number of renewable energy sources and distributed generators requires new strategies for the operation and management of the electricity grid in order to improve the power-supply reliability and power quality (PQ). However, power quality compensation i.e. voltage sag, swell, harmonics reduction in current and voltage waveform are the real problem in power flow between microgrid and loads. Unified power quality conditioner (UPQC) is a device which can mitigate all PQ related problem in both utility and microgrid system. In the proposed system PV/Wind/Fuel cell/Battery are connected to a common bus where different loads are connected and UPQC is integrated with the microgrid and grid to compensate PQ related problem. The simulation model of series active filter, shunt active filter, UPQC and microgrid system are design in MATLAB software and results are verified by using First Fourier Transform analysis. The study concludes with a comparison between the microgrid side disturbances and grid side disturbances, and it is observed that the harmonics in source current is reduce below 5% in all cases and also compensate the voltage sag and swell..
关键词：microgrid system; solar PV; wind system; fuel cell; power quality; unified power quality conditioner
