Enhancement of power quality on grid connected dual voltage source inverter

This paper presents a dual voltage source inverter (DVSI) system to augment the power quality and reliability of the microgrid system. The proposed scheme is comprised of two inverters, which enables the microgrid to substitute power generated by the distributed energy resources (DERs) i.e photo-voltaic system and furthermore to compensate the local unbalanced and nonlinear load. The control algorithms are developed based on instantaneous symmetrical component theory (ISCT) to activate DVSI in grid sharing and grid injecting modes. The proposed design has better reliability, minor bandwidth requirement of the main inverter, lower cost due to reduction in filter size, and better consumption of microgrid power while using reduced dc-link voltage rating for the main inverter. These characteristics make the DVSI design a capable option for microgrid supplying sensitive loads. The topology and control algorithm are validated through extensive simulation results through MATLAB/SIMULINK.