Conceptualization and Experimental Assessment of Design Aspects for 3-Level ANPC Inverters

Abstract:
The active neutral-point-clamped (ANPC) inverter topology offers many degrees of freedom, which must be considered in its design and control. The ANPC’s sophisticated structure allows for redundant switching states, enabling several distinct modulation schemes. The selection of semiconductor components and the applied cooling may help distribute losses across the topological switches and offer a way to equalize junction temperatures. The design space is highly diverse, and very different approaches and designs can lead to similar performance. In addition, these degrees of freedom come with specific requirements, which must be considered in the hardware and especially the commutation loop design. This work, therefore, summarizes the design aspects for the 3-level ANPC topology. The design of a highly flexible 3-level ANPC experimental platform is described, which provides the basis for future experimental evaluations of the highlighted possibilities. As part of the commissioning of this platform, switching characteristics for the available commutations within the different modulation schemes are investigated experimentally in this work.