Topological Analysis and Solar Grid-Tied Integration of Level Building Network Based Extendable High Power Multilevel Converter

Abstract

This paper presents a new solar multilevel converter (SMLC) with closed-loop control to integrate solar PV arrays with medium voltage 3.3 kV grid. This multilevel converter produces higher number of levels in the output voltage with less usage of semiconductor switches. This solar converter utilizes only ten switches and three PV sources with equal voltage to have seven levels in the output voltage. The main motive is to have minimum switches, which reduces the count of driver circuits for a power converter. Moreover, a reduced switch converter requires less space in terms of installing the power and auxiliary components. This solar power converter comprises a solar photovoltaic (SPV) array fed level building network (LBN) nested within the six switches connected in a rectangular arrangement. The converter has two PV sources at its upper and lower ends. This solar converter is also ideal for asymmetric configurations. Moreover, the increase in solar input power is possible with more count of the LBNs. The converter switching states and operating path demonstrate the working operation of the new solar PV system. A comparison of the proposed solar converter is made with existing multilevel topologies. The system is modeled and executed in closed-loop control to showcase its effectiveness for solar power conversion. The solar converter transfers the power in varying solar conditions successfully.