Construction And Testing Of A 13.8 Kv, 750 Kva 3-Phase Current Compensator Using Modular Switching Positions

Availability of high-voltage power modules based on silicon carbide (SiC) is enabling the realization of multilevel topologies to solve a variety of issues in power distribution systems. However, the relatively low voltage ratings of currently-available semiconductor devices increase the complexity of the required solutions. Stacking lower-cost and lower-voltage devices to derive a higher-voltage switch can help reduce system complexity at the expense of more a complex switching position. Thus, this stacking solution comes with its own set of challenges. This paper presents the design and experimental results for an 11-level 13.8 kV neutral-point-clamped flying-capacitor converter that uses stackable switching positions for three-phase current compensation in a distribution system. The converter is successfully used for direct grid-connection and upstream current compensation with a 4.16 kV(LL) grid.