100kva electrical power transformer price Ai Power offers three phases, oil immersed, and naturally cooled distribution and power transformers. Our products from 10kva to 20000kva with a maximum voltage 35kv are manufacture under the standard of IEC60076. The windings are made of high-grade electrolytic cooper and are concentrically positioned. Usually copper foil is used for the low voltage windings. Round shaped, enamel insulated wires is used for the high voltage windings.