A Simulation Analysis of Grid Synchronized H- Bridge Multilevel Inverter with PV Module – An Open Loop Study

ABSTRACT: In the power generation sector, Natural Resources like Solar, Wind, Tidal, Geothermal, Hydro etc have always played a very important role. Out of these solar PV (photo voltaic) is most popular due to its significant advantages. However the solar radiation never remains constant. It keeps on varying throughout the day. In this paper, single 60 W solar PV panel along with boost converter have been interfaced and control for a three phase three-level neutral point clamped inverter (NPC) for grid connected photovoltaic (PV) system. The need of the hour is to deliver a constant voltage to the grid irrespective of the variation in temperatures and solar isolation. The maximum power point tracking (MPPT) is capable of extracting maximum power from the photovoltaic (PV) array connected to each DC link voltage level. The MPPT algorithm is solved by Perturb & Observe method. We have designed a circuit such that it delivers constant and stepped up dc voltage to the load. We have studied the open loop characteristics of the PV array with variation in temperature and irradiation levels. Then we coupled the PV array with the boost converter in such a way that with variation in load, the varying input current and voltage to the converter follows the open circuit characteristic of the PV array closely. At various isolation levels, the load is varied and the corresponding variation in the input voltage and current to the boost converter is noted. It is noted that the changing input voltage and current follows the open circuit characteristics of the PV array closely.