Solid-state transformers: companies, research and applications

Delta Electronics, Siemens AG, Infineon Technologies, ABB Group and Enphase Energy are active in the field. Siemens and Reinhausen announced SST development for data centers in August 2026. Enphase has been developing its IQ Solid-State Transformer for AI data centers, while Infineon has announced partnerships focused on SST power infrastructure.

Xi'an Jiaotong University, North China Electric Power University and Zhejiang University are among the research organizations active in SSTs. Xi'an Jiaotong University has studied direct AC-AC conversion and a 35 kV design. Zhejiang University reported a validated 2 MW, 10 kV medium-voltage SST, while North China Electric Power University works on simulation and multi-AC-port operation.

The recorded grant total is $52,041,317 across 37 awards since 2020. The funding data also includes other rounds that may relate to organizations active in the broader field rather than SST development specifically. One directly relevant company announcement is Heron Power's $140 million Series B in February 2026, reported as support for a planned manufacturing facility.

Heron Power announced a $140 million Series B in February 2026. The company said the financing would support a planned manufacturing facility for its solid-state transformer product. This is a company-specific funding announcement; broader funding records also list rounds for organizations active in power electronics, but not all are explicitly tied to SST projects.

Delta Electronics Inc leads the listed patent holders with 8 patents in the window. Trumpf Huttinger Gmbh Co. Kg follows with 7, while ABB Schweiz AG holds 4. Huawei, Delta Electronics (Shanghai) and Siemens Energy Global each appear with 3 listed patents.

No: the recorded 136 patents in the 24-month window accompany a 34.1% decline in patent activity over the last 12 months versus the previous 12 months. Publications were comparatively steady, with 706 in the last year and a 0.6% decrease. This points to a field where research remains active even as patenting has eased.

Recent demonstrations and product development show progress toward practical deployment, though reliability and integration remain important engineering challenges. In August 2026, North Carolina State University, the New York Power Authority and EPRI reported a real-world SST demonstration capable of handling up to 1 MW. Siemens and Reinhausen announced development for data centers, while recent research addresses insulation, protection and resilient control.

The main approaches are three-stage isolated conversion, two-stage conversion, direct AC-AC conversion, modular multilevel architectures and wide-bandgap switching. Three-stage designs offer flexible isolated conversion but add components. Two-stage and direct AC-AC designs reduce conversion stages but increase control demands. Modular multilevel designs support scalable voltage, while wide-bandgap devices enable faster switching with thermal and insulation trade-offs.

The United States leads the recorded activity with 3,253 documents, followed by China with 3,025. Germany has 1,536, India 1,362 and Japan 1,274. These figures indicate where relevant research and industry activity is concentrated in the dataset; they do not measure installed SST capacity or commercial deployments.

Recorded applications include renewable energy and storage, grid distribution and microgrids, data-center power, electric-vehicle charging, and rail and transport electrification. Renewable energy and storage has 704 documents, while grid distribution and microgrids has 625. Data-center power is a growing area, with recent designs and company activity targeting AI infrastructure.