Cascaded Multilevel Converter for Micro Grid Application

The concept of multilevel inverters, introduced about 20 years ago entails performing power conversion in multiple voltage steps to obtain improved power quality, lower switching losses, better electromagnetic compatibility, and higher voltage capability. The benefits are especially clear for medium-voltage drives in industrial applications and are being considered for future naval ship propulsion systems. Several topologies for multilevel inverters have been proposed over the years; the most popular cascaded H-bridge apart from other multilevel inverters is the capability of utilizing different dc voltages on the individual H-bridge cells which results in splitting the power conversion amongst higher-voltage lowerfrequency and lower-voltage higher-frequency inverters. This paper presents a single-phase multistring Multi-level photovoltaic (PV) inverter topology for Micro gridconnected PV systems with a novel hybrid H- bridge inverter.