A highly efficient PV power system for DC MicroGrids

Climate change attracted widespread attention to shift towards environmentally friendly energy sources such as photovoltaics. Considering the facts that there are large numbers of DC loads that are used in today's buildings, the existing infrastructure is an AC power system, and the PV is a DC source, there will be power losses in the DC-AC-DC conversions. Therefore, the concept of using a DC MicroGrid can provide more efficient power to native DC loads directly from the DC green sources, with minimum conversions. This paper attempts to design a highly efficient power system for a DC MicroGrid. One building at Qatar University is selected and considered as a case study for the DC MicroGrid system integration. This paper discusses also the simulation of PV modeling and the maximum power point tracker using Matlab/Simulink. In addition, a feasibility study is carried out to investigate the viability of the system design through the implementation of two DC-DC converters: interleaved boost converter for the PV system and bidirectional buck converter for the energy storage system. The results are very satisfactory.