Siemens and Reinhausen (formerly Maschinenfabrik Reinhausen) have formed a strategic partnership to develop and industrialise a solid-state DC transformer for up to 36 kV grid voltage. The technology is being developed specifically for deployment in AI data centres.
Artificial intelligence is said to be driving a fundamental transformation of data centre infrastructure. The industry is moving from traditional power architectures towards more efficient and scalable solutions capable of supporting the next generation of AI workloads. Solid-state transformers are one of the key building blocks of that transition. AI-ready data centres and high-density power infrastructures are increasing the requirements for medium-voltage connection, power density, efficiency, and availability.
For an 800 VDC distribution system, a medium-voltage solid-state transformer, usually referred to as a DC transformer, provides a compact, efficient, and galvanically isolated alternative to conventional multistage AC/DC power-conversion architectures. In this architecture, medium-voltage AC is converted to 800 VDC and distributed to the data centres, reducing intermediate conversion stages and enabling more efficient power delivery to high-density AI infrastructure.
In principle the digital device works by chopping an ac curve into very short lengths of DC, transforms the pulsing curve that results and smooths it back into DC at whatever voltage level is desired.
“Combining the technological strength of Siemens and MR will shape the future of power solutions for AI data centres. Solid-state transformers are critical for these large and power intensive structures. They enable higher efficiency, direct grid-to-rack DC conversion, and a reduced footprint. By responding to load changes in milliseconds, they seamlessly handle the extreme power swings of AI training workloads and avoid downtime while cutting costs. This collaboration will further strengthen our leading position in the electrification of data centres,” said Stephan May, CEO of Electrification and Automation at Siemens.
Key features of the offering include modularity, scalability, and high availability. The design supports operation up to 36 kV and can be applied to lower voltages, making the architecture scalable for different grid-connection conditions. It delivers a stable 800 VDC output for applications that require a stable DC-link voltage and direct coupling to downstream DC distribution or load systems. The SST design is built around clearly defined interfaces, and protection technology to support reliable operation in demanding infrastructure environments.
