High power voltage transformers (SSVTs) – Type VPT
Building on the principles of inductive voltage transformer design, the high-power voltage transformer, also known as station service voltage transformer (SSVT), is engineered to supply auxiliary power for substations and enable rural electrification. The open-core concept provides several operational advantages over conventional products. These include immunity to ferroresonance, explosion-proof construction, and robust resistance to very fast transient overvoltages.
Offered with rated voltages ranging from 72.5 kV to 550 kV, the VPT transformer is a testament to the company’s innovation, with serial production launched in 2006.

Additional design features:
- Custom-made design – tailored to individual customer requirements
- Rated power ranging from 5 to 333 kVA
- Available in variants with low-voltage secondary windings (up to 1000 V) or medium-voltage secondary windings (up to 7.2 kV)
- Option to integrate measuring windings
- Partial discharge-free under AC test voltage
- Unique open-core magnetic design – immune to ferroresonance
- Robust insulation system designed to withstand very fast transient overvoltages
- Explosion-proof design, inherently resistant to internal electrical arcs
- Oil expansion effectively managed by a stainless-steel membrane
- Broad operational temperature range from -60 to +60 °C
- Available in biodegradable insulating fluid-filled configurations
- Proven reliability in seismically active environments
- High operational safety with minimal maintenance requirements

