IEC Releases Power Transformer Standard - IEC 60076-15

April 26, 2008 // Published as a news service by IHS

A gas-filled transformer is a transformer whose magnetic circuit and windings are enclosed with an insulating gas. Sulfur hexafluoride (SF6) gas is generally used. Such a transformer is sometimes referred to as a gas-insulated (GIS) transformer, said the IEC.

Experts say that these types of transformers offer certain advantages when space is in short supply or where they have to be housed internally or underground, said the IEC.

Katsutoshi Toda of Toshiba Corp., who is project leader for Power Transformers Technical Committee (TC) 14 and project leader for IEC 60076-15, said, "There has been a rapid increase of gas-filled transformers and reactors particularly in southeast Asian countries like China, Japan, Korea and Singapore.

"Plans to construct indoor or underground substations accelerate this trend because of the difficulty in acquiring land for substations in large cities where electric power demand is concentrated.

"Requirements of security against fire accidents, compactness and total cost reduction are the key factors for these substations. Total gas-insulated substations combining [gas-insulated] GIS and gas-filled transformers meet these needs."

With the U.N. forecasting that half the world's population will live in urban areas by the end of 2008 and about 70% will be city dwellers by 2050, there will be an increase in the demand for electricity, according to the IEC.

To meet this need, authorities and utilities will have to build new substations, said the IEC. Because city land is scarce and expensive, many of the new substations will have to be built indoors or underground. Therefore, the demand for gas-filled transformers can be expected to increase, said the IEC.

IEC 60076-15 is for those who design, construct, purchase or operate gas-filled transformers and for those who plan or construct the substations in dense city areas. Australia and the U.K. are among the countries using these transformers, Toda said.

Gas-filled transformers (up to 330 kilovolts-400 megavolt ampere class) operate in the field of electric power utilities and industrial firms.

Source: International Electrotechnical Commission (IEC).