Schmidbauer Transformatoren und Gerätebau
Schmidbauer Transformatoren und Gerätebau is a German family-founded manufacturer of transformers, chokes and inductive components, established in 1949 in Hebertsfelden, Lower Bavaria.
Schmidbauer was founded by Ignaz Georg and Margarete Schmidbauer as a transformer repair business and has remained family-run through three generations. The group employs just over 200 people across two production sites — Hebertsfelden in Germany and Blovice in the Czech Republic — according to the October 2025 announcement.
In October 2025, the Japanese Sumida Corporation acquired an 80 per cent majority stake in the company. Schmidbauer states that it remains an independent company while gaining access to Sumida’s international development, production and sales network as the business unit Power Industry.
Rail products
For rail, Schmidbauer manufactures isolating transformers for vehicle power supply, chokes, reactors and medium-frequency transformers. Isolating transformers provide galvanic separation between primary and secondary windings — a standard safety function in onboard power supply and electrification architectures.
Railway transformers are available for 50/60 Hz as well as medium- and high-frequency operation, in different vector groups. The company also supplies water-cooled reactors for water-cooled inverter systems.
Unlike traction transformers that step down catenary voltage, Schmidbauer’s rail portfolio centres on auxiliary and isolating functions within the vehicle’s electrical system.
Manufacturing and certification
Schmidbauer applies vacuum-pressure impregnation (VPI) in polyesterimide resin, a process the company introduced specifically for waterproofed railway transformers and reactors. VPI reduces noise levels and extends component life.
Materials are tested to the fire protection standard EN 45545 and fulfil hazard level HL3 as standard. The company is certified to DIN ISO 9001:2015.
Isolating transformers are built with outputs up to 2.5 MVA. Production covers unit weights up to five tonnes.
Current activity
Beyond rail, Schmidbauer supplies inductive components for battery test centres, electromobility, machine tools and CERN’s particle accelerator. The Sumida shareholding, announced in October 2025, marks the most significant structural change in the company’s recent history.
