This design implements a three-phase solid-state transformer (SST) based on a silicon carbide (SiC) power module. Using a modular architecture allows for stacking multiple converter submodules in series to meet medium-voltage grid requirements. Using fast switching SiC devices enables the DC/AC stage to switch at 10kHz and the dual active bridge (DAB) isolation stage at 100kHz, which reduces the size of the high-frequency magnetic components and increases the overall power density. Inter-module communication provide the high isolation voltage levels required in medium-voltage end equipment. The cascaded topology distributes the grid voltage evenly across submodules, allowing the use of standard lower-voltage rated SiC devices while maintaining full medium-voltage operation.
Merkmale
- 50kW rated reference design with modular and scalable architecture.
- Medium-voltage DC link rated at 2.2kV, low voltage DC link at 1.5kV.
- SiC power module based H-Bridge converter on the medium-voltage side.
- Dual active bridge (DAB) for isolated DC/DC conversion stage switching at 100kHz.
- DC/AC converter switching at 10kHz in unipolar mode.
- Fiber optic communication between submodules providing the required isolation voltage.
- Bidirectional power flow capability supporting gridto-storage and storage-to-grid operation.
- Single module dimensions: 850mm × 300mm × 80mm.