Dyna-C: A topology for a bi-directional solid-state transformer

This paper presents a compact bi-directional solidstate transformer (SST) based on a current-source topology, featuring high-frequency galvanic isolation and only two minimal power conversion stages. The topology, referenced as Dynamic Current or Dyna-C, can be configured for multiterminal DC and/or multi-phase AC applications. The Dyna-C is robust, can be stacked for MV applications, and be paralleled for high current and high power applications. The paper will present some of the possible configurations of Dyna-C, and will discuss challenges associated with the control and operation. One core innovation presented in this paper is the management of transformer leakage energy when transitioning from one bridge to another while maintaining low device stresses and losses. Simulation and experimental results are used to validate operation of the topology.