Analysis and Design of a Novel Six-Switch Five-Level Active Boost Neutral Point Clamped Inverter

Abstract

This article presents an analysis and design of a new boost type six-switch five-level (5L) active neutral point clamped (ANPC) inverter based on switched/flying capacitor technique with self-voltage balancing. Compared to major conventional 5L inverter topologies, such as neutral point clamped, flying capacitor, cascaded H-bridge, and ANPC topologies, the new topology reduces the dc-link voltage requirement by 50%. Whilst reducing the dc-link voltage requirement, the number and the size of the active and passive components are also reduced without compromising the reactive power capability. The analysis shows that the proposed topology is suitable for wide range of power conversion applications (for example, rolling mills, fans, pumps, marine appliances, mining, tractions, and most prominently grid-connected renewable energy systems). Experimental results from a 1.2 kVA prototype justifies the concept of the proposed inverter with a conversion efficiency of around 97.5% ± 1% for a wide load range.