Investigation of a Modular AC Stacked Pure Sine Inverter for Low- Voltage Grid Storage Applications

Inhalt:
This paper presents an innovative modular inverter concept for grid-connected battery energy storage systems. The approach particularly targets the second-life utilization of EV battery modules. By series connection of the inverter modules at the AC side, this concept allows for an encapsulated switching cell design based on cost-effective low voltage silicon devices. High switching frequencies, modularity and the resulting multi-level topology provide advantageous system properties in comparison with conventional systems. This publication focuses on the fundamental inverter concept. The modeling and control of the overall system is also considered. In addition, this paper demonstrates a first hardware implementation of the system. Corresponding measurement results validate it’s basic functionality.