Fig.  (23) Bushing type GOEK 1425 for direct connection of 420 KV Power Transformer to gas insulated Switchgear or high voltage cable
 


Fig. (24) Cut away view of Transformer bushing type GOE

Construction of Cable Connection and GIS Connection

Cable Connection

 

In urban-district substations connected with power cables and thermal power stations suffered from salt-pollution, cable direct-coupled construction is used in which a Transformer is direct-coupled with the power cable in an oil chamber.

Indirect connection system in which, with a cable connecting chamber attached to the Transformer tank, a coil terminal is connected to the cable head through an oil-oil bushing in the cable connection chamber. Construction of the connection chamber can be divided into sections. Cable connections and oil filling can be separately performed upon completion of the tank assembling.
 


Fig. (26) Indirect Cable Connection
GIS (Gas Insulated Switchgear) Connection

There is an increasing demand for GIS in substations from the standpoint
of site-acquisition difficulties and environmental harmony.

In keeping with this tendency, GIS connection-type Transformers
are ever-increasing in their applications.

The SF6 gas bus is connected directly with the Transformer
coil terminal through an oil-gas bushing. Oil-gas bushing support
is composed of a Transformer-side flange and an SF6 gas bus-side flange,
permitting the oil side and the gas side to be completely separated from each other.


Fig. (27) Direct GIS Connection