ABB’s first 250 MVA, 400 kV fast-deployable transformer uses DuPont™ Nomex® insulation for high output and compactness 

ABB’s new fast-deployable transformer with hybrid insulation of DuPont™ Nomex® combines an exceptionally high power/voltage rating of 250 MVA, 400 kV with significant size and weight reduction for rapid transport mobility and fast deployment. 

How was this possible?

Key to the breakthrough was the decision to use a high temperature class hybrid insulation system with DuPont™ Nomex® paper and pressboard, enabling ABB to design very compact transformer windings, yet achieve an unusually high power capacity compared with conventional cellulosic insulation.

The challenge

Mobile transformers play a vital role for many distribution grid operators in providing rapid emergency power in case of failure or downtime of the main HV unit. But typical mobile units are rated below 100 MVA to comply with shipping dimension and weight restrictions. This makes them incapable of supplying power in 220- 400kV transmission grids.

The solution

ABB conducted a feasibility study to evaluate the technical challenges involved in developing a cost-effective fast-deployable transformer with the same output as considerably larger and less mobile units. The question was — how could the company achieve such seemingly conflicting objectives by combining the step-up in power capacity with outstanding mobility? 

For the remaining details, click to see the full case study below: 

ABB’s new fast-deployable transformer