Multi Input DC-DC Converters for Rooftop PV Power Systems

Abstract

The rate of using solar power as electrical energy source is increasing dramatically nowadays and with the development of semiconductor technologies it is expected that a significant proportion of electrical energy production will depend on this field of study. Therefore, there are many researches in order to have efficient usage of solar power.In this paper, a power electronics system that is employed for transforming the electrical energy of PV panel to a suitable form, is presented. The system consists of four separate PV panel and for each panel four DC-DC push-pull converters whose outputs are parallel connected at the end. On the other hand, control of the system includes incremental conductance methods for maximum power point tracking (MPPT) and interleaving technique where the control of whole system is achieved with a single DSP.In order to predict system operation, detailed simulation has been created in MATLAB/Simulink environment. According to result, at least 94% efficiency across the push-pull converters and 99% of MPPT efficiency are achieved. Additionally, it is observed that sustainability and efficiency are increased by paralleling four separate PV system and using interleaving technique which results in reduction of output filter size.