Autotransfomer 600 MVA 525 kV – USA

Transformer 36 MVA - 90 kV – France

Power transformers: the manufacturer’s experience serving its customers

Since the early 50’s, all HV and EHV transformers, both medium and large power, are designed and manufactured in Lyons, France at JST transformateurs’ plant. 

Our reputation is derived from our relationship with customers of electrical generation, transmission and distribution, as well as of railway feeders electrical supply, and of major industrial sites. 

Our experience in large scale projects, our close communication with customers, our flexibility to listen to and implement their needs, as well as our deep knowledge of both transformer design technologies – Shell type and Core type – are the keys to our success.

> Large Power :
    Shell type technology

> Medium Power :
    Core type technology

Large Power – Shell type technology

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Shell type technology is normally used for large power EHV transformers (above 220 kV and up to 800 kV), as well as for complex units such as phase shifters.


Commonly used in many countries, from USA to China and from Europe to Japan, its main assets are as follows:

  • Natural withstand to short-circuit stresses
  • High flexibility level towards impedances, allowing particularly low values
  • Low weight and dimensions leading to reduced layout, transportation and civil works constraints
  • Reduced needs in raw materials, in particular regarding oil, thus more environmentally friendly

With this technology, JST transformateurs succeeded as early as in 1968 in the world first short-circuit test on a 300 MVA 400/220 kV autotransformer.

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Medium Power – Core type technology

For HV medium power transformers (50 to 230 kV, 15 to 200 MVA), our experience in core type technology allow our customers a technically reliable and economically optimized solution. Whatever the application – step-up transformers for generating plants, step-down transformers or autotransformers for transmission and primary distribution networks – our domestic and export references confirm our know-how.

In addition, our references in the supply of demanding industrial processes via our rectifier transformers and the railway feeder supply back up JST’s reputation as an industry leader. 

moyenne_puissance

Autotransfomer 600 MVA 525 kV – USA

Transformer 36 MVA - 90 kV – France

Power transformers: the manufacturer’s experience serving its customers

Since the early 50’s, all HV and EHV transformers, both medium and large power, are designed and manufactured in Lyons, France at JST transformateurs’ plant. 

Our reputation is derived from our relationship with customers of electrical generation, transmission and distribution, as well as of railway feeders electrical supply, and of major industrial sites. 

Our experience in large scale projects, our close communication with customers, our flexibility to listen to and implement their needs, as well as our deep knowledge of both transformer design technologies – Shell type and Core type – are the keys to our success.

> Large Power :
    Shell type technology

> Medium Power :
    Core type technology