Grid Integration of Multistring Photovoltaic Plants with Modular Multilevel Converter

This paper presents the application of Modular Multilevel Converter (MMC) for connecting multistring photovoltaic generation plant. The proposed approach makes it possible for an increased PV plant capacity to be integrated with the grid, while also improving efficiency of conversion and power quality. To increase the efficiency of individual PV module, a DC-DC boost converter is employed with maximum power point tracking (MPPT). The MPPT is implemented by employing Perturb & Observe (P&O) algorithm. The PV modules with DC-DC boost converters are connected in parallel to form a DC bus which is connected to the utility grid with MMC. The MMC inverts the DC bus voltage for interfacing to the grid while maintaining the DC bus voltage constant.  The simulation of the overall system in Simulink/MATLAB verifies the validity of the proposed system. 

Ahmad Kamal, Abdul Basit "Grid Integration of Multistring Photovoltaic Plants with Modular Multilevel Converter" International Journal of Engineering Works, Vol. 5, Issue 2, PP. 16-20, February 2018.                                                                      

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