New Transformer for Data Centers

August 14, 2026

Source: E & M powernews

Siemens and Reinhausen plan to develop a solid-state transformer for medium-voltage grids up to 36 kV that will supply AI data centers with 800 V DC.

Development partnership between Siemens and Reinhausen: The Munich-based conglomerate and the Regensburg-based company specializing in transformers plan to design an SST to power AI data centers. The abbreviation stands for solid-state transformer. According to Siemens, the SST is to be designed for grid voltages up to 36 kV and generate 800 V DC.

Medium-voltage-capable SSTs are considered an efficient alternative to conventional multi-stage AC/DC conversion architectures. They convert the voltage directly and have higher efficiency. SSTs also respond to load changes within milliseconds and can compensate for extreme power fluctuations.

The technology is not new. Several vendors are already working on SST solutions for the 800-VDC architecture of data centers. The U.S. manufacturer Eaton, for example, describes a medium-voltage SST that converts medium-voltage AC directly into DC or low-voltage AC and supports 800-VDC systems. According to the manufacturer’s data sheet, the SST is designed for the 15-kV voltage class, has a power rating of 2 MW, and an efficiency of over 97 percent.

The Chinese inverter manufacturer Sungrow also unveiled an SST solution tailored for AI data centers in 2026. In July, the company announced the launch of an SST that converts medium-voltage AC directly to 800 V DC for AI applications. Its output is rated at 3 MW, with an efficiency of up to 98.5 percent.

In its press release, Siemens does not provide any details on power output or efficiency, nor on the timeline for market launch. According to the company, it is bringing expertise in power electronics, energy supply, grid protection, automation, and digitalization to the development partnership. Reinhausen is expected to contribute, among other things, experience in voltage regulation, power quality, grid stability, and medium-voltage power electronics.

Author: Manfred Fischer