Analysis of photovoltaic fed modular multilevel converter with reduced switch count under source failure condition

摘要

A three phase photovoltaic (PV) system interfaced with hybrid cascaded modular multilevel (HCMMLI) inverter is proposed in this paper. Utilizing PV as DC source, the MLI for three phase circuit is designed and implemented. The circuit arrangement of proposed inverter possess following advantages as reduced switch count, less switching loss and low voltage stress and less converter cost compared to conventional multilevel inverter topology (MLI). Photovoltaic system provides necessary dc source to the proposed converter topology. Maximum peak power tracking (MPPT) method is carried out to trace peak point from PV system. The whole structure is analyzed under PV panel failure condition and operated the nearest level technique is used as a control method to produce switching sequence to the proposed converter and in addition, the comparative study on the performance analysis is performed with conventional MLI topology. Experimental validation has also been carried out based on simulation study.