Abstrakt

Hybrid Modulation Switching Strategy for Grid Connected Photovoltaic Systems

Brindha.P, Kaliamoorthy.M, Arul prasanna.M, Rajasekaran.V

This work presents a novel single phase cascaded H-bridge multilevel inverter with least number of switches and isolated DC sources. The proposed inverter consists of two H-bridges connected in cascade. The upper H-bridge consists of five power electronic switches, capable of developing five level output and the lower H-bridge is capable of developing multilevel output. The conventional CHB inverter is replaced with the additional bi-directional switches in each cell. The proposed inverter consists of two H-bridges, the upper Hbridge is replaced with the addition of one bi-directional switch and the lower H-bridge is replaced with the bidirectional switches driven by hybrid modulation switching strategy. The upper inverter is switched at high frequency and the lower inverter is switched at low frequency. Hybrid modulation switching strategy is used to generate the multilevel output for the proposed inverter. The proposed inverter will be compared with the existing multilevel topologies on the basis of number of components, number of isolated DC sources, Switching losses and converter losses. The proposed inverter will be connected to the grid by proper synchronization along with maximum power point tracking algorithm. The proposed grid connected multilevel inverter will be simulated using MATLAB/SIMULINK and will be implemented in hardware using SPATRAN3A DSP.