Low-Voltage Dc Microgrid Network: A Case Study For Standalone System

In this paper a novel technique is used to aggregate power of the distributed renewable energy sources, especially the photovoltaic energy. The DC/DC converter is the main instrument for extracting the energy from these direct current (DC) renewable energy sources like solar photovoltaic module (PV), wind turbine, and fuel cell, etc. The reason for using DC/DC boost converter in this case of PV energy is for two reasons. Firstly, the maximum output voltages of PV modules at standard test condition (STC) are low in range of 30 to 45 volts. Secondly, DC voltages are being considered as standard by corporates like Emerge-alliance for lighting systems in green energy building. The paralleling of DC/DC converter boost converters helps in aggregation of varying power from these converters connected to different power rating PV modules under varying irradiation and in regulation of 48 volts DC at load terminal. To obtain the aggregate power from the parallel DC converters, this paper proposes a systematic approach for power sharing between converters under varying irradiance. The integrated circuit (IC) UC3843 is based on current mode control and it is the heart of the DC converters used in this proposed work. The cable resistance is another disturbing factor in regulation of the set standard DC voltage. With above mentioned factors, PV module of low power with current mode boost controlled DC converters is implemented and the simulation and experimental results are discussed.