F-Type Single Phase Five Level Inverter

Abstract

In modern industrial and power electronics applications, high-voltage and high-current integrated modular power transistors (IGBTs) are increasingly being utilized. The F-type inverter, which is a modified version of the T-type inverter, has emerged as a promising option. This configuration separates the common point of the bidirectional power switch, reducing voltage stress and resulting in lower inverter costs and losses. The F-type inverter has a simplified design and lower conduction losses, making it a viable choice for medium-voltage applications compared to the clamp diode NPC inverter configuration. Detailed analysis of losses and efficiency has been conducted, and a simulation and experimental prototype have been built to validate the theoretical basis. In addition, the voltage rating of the power switches in the T-type three-level inverter is a limiting factor, as it is only 50% of the input DC voltage for each inverter phase leg.