Solar/Wind transformer is meant for converting the low voltage into high voltage and fed into a power grid. Thus this transformer is also known as Convertor Duty or Inverter Duty transformer.
The transformer is designed in such a way that it can resist Harmonic currents caused by rectifier/inverter. Also, a Copper static shield is provided earthen separately to resist radio frequent disturbance. For such transformers, the design is done with multiple winding, for example, three winding or four winding transformers which make 6 pulses and 12 pulses transformer.
Maintaining proper mechanical and electrical properties is the crucial part of designing such transformer ensuring good performance with the safety of all the electrical equipment.