• Cheeli Rama Krishna
• Mrs. J. Hema Latha

The multilevel inverter with disunite dc sources is a better choice as an interface between the grid and distributed energy resources (DERs). The point of common coupling (PCC) has the tremendous role in the grid-connected applications, for that voltage quality at the PCC is most important than the inverter output voltage. This paper brings a fundamental frequency switching method to mitigate voltage harmonics for the grid-connected cascaded H-bridge multilevel inverter at the point of common coupling (PCC). In this paper first, the harmonic mitigation by using the conventional switching method was presented, after that, a Genetic Algorithm optimization based program proposed to minimize the THD of the PCC voltage and the harmonic contents of the inverter output voltage. Here the main aim is to calculate optimum switching angles of the inverter. These switching angles must satisfy the standard limits for the inverter output voltage and the total harmonic distortion by considering the specifications of the grid. The switching angles are to be employed for a seven-level cascaded h- bridge multilevel inverter connected to an ac power grid. The conventional method and the GA optimization method for calculating switching angles were implemented in MATLAB/Simulink environment. The results show the effectiveness of the genetic algorithm optimization method.

Multilevel inverter, Switching angles, Point of common coupling, THD, GA optimization.

"Switching Angle Estimation and THD Minimization in the Grid-Connected Multilevel Inverter", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.5, Issue 7, page no.617-627, July-2018, Available :http://www.jetir.org/papers/JETIR1807985.pdf

"Switching Angle Estimation and THD Minimization in the Grid-Connected Multilevel Inverter", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.5, Issue 7, page no. pp617-627, July-2018, Available at : http://www.jetir.org/papers/JETIR1807985.pdf