CPS-SST: A Single-Stage AC–DC Solid-State Transformer Based on the Converter PWM Switch Concept

This paper proposes a new single-stage topology for medium-voltage AC (MVAC) to low-voltage DC (LVDC) solid-state transformers (SSTs) based on the recently introduced Converter PWM Switch (CPS) concept and the input-series output-parallel (ISOP) architecture. The proposed CPS-SST features a wide ZVS range, low turn-off loss, high efficiency, a reduced number of active switches, and simple PWM control. A module-rotation multilevel modulation strategy is introduced to reduce the required inductance value, while ensuring balanced power sharing among modules in the CPS-SST. The ZVS performance and turn-off current characteristics are analyzed in detail, and a comprehensive loss model is presented and compared with that of a conventional two-stage ISOP SST. A 10 kW CPS-SST module is constructed and experimentally validated, achieving a peak efficiency of98%at 5.8-kW. The experimental results closely match the analytical predictions, confirming the strong potential of the proposed topology for MV power conversion applications.