LIQUID FILLED POWER TRANSFORMERS

GBE S.p.A. produce oil filled power transformers up to 50 MVA, with rating class up to 145 kV BIL 650 kV ONAN/ONAF/OFAF. For special hermetically sealed solutions, the tank itself can be provided with internal

nitrogen cushion. The company is also specialized in repairing different types of others oil filled power transformers. All Manufacturing program is made according to IEC 60076.

HIGH VOLTAGE AND MEDIUM VOLTAGE WINDINGS:

The primary and secondary windings of oil filled transformers are made with electrolytic copper (for small power range on customer request the windings can also be made in Al), with insulation in pure cellulose paper. The choice of windings type depends on the required voltage and power range. Every high and low voltage winding layer is insulated with pure cellulose paper sized in such a way as to withstand all mechanical and electric stress. Oil filled power transformers are made with disk windings of the typology adequate to the voltage and currents involved. For higher currents, transposed cable or other alternative

solutions are applied.

ON LOAD AND OFF LOAD TAP CHANGERS:

The adjustment or variation of the primary voltage is done with linear tap changers in oil bath and maneuverable with the transformer disconnected by knobs placed on the tank cover or with OLTC (On Load Tap Changer) that allow to tap while the transformer is on-load. The on load tap changers OLTC may be equipped with different accessories upon customer request. GBE S.p.A. offer also customized motor driven on load tap changers.

TANK WITH COOLING RADIATORS:

The power transformers tanks are realized with high resistant laminated steel with mould supports to guarantee vacuum withstand up to 1 bar, when specified. All power transformers are supplied with

special developed radiators made with cold rolled and laminated steel and if required, hot dip galvanized treatment. All radiators can be delivered disassembled and they are provided with safety valve welded to the tank. The outside walls are protected with water resistant bi-component paint RAL 7031 or RAL 7033 suitable to guarantee painting class up to C5M.