OIL
POWER
TRANSFORMERS
Made with grain oriented magnetic laminations cut at 45° and assembled with the step lap method.
INSULATING OIL
Filled with PCB-free oil that has been dried and degassed, and complies with IEC standards.
WINDINGS
Made mainly of electrolytic copper, with pure cellulose paper conductor insulation.
TANK
Made of high-strength sheet steel on which oil cooling radiators are mounted.
APPLICATIONS
GBE supplies oil power transformers up to 50 MVA and voltages up to 145kV (BIL 650), with no-load or on-load switching. The switch can be either external or internal.
Oil power transformers are made with constructional and design criteria that ensure the highest operational reliability and great electrodynamic performance, while guaranteeing excellent insulation against mains overvoltages.
The magnetic core is made using high impermeability laminations with 45° cut lines and step lap construction. The lamination clamps are dimensioned to ensure mechanical tightness, reducing noise and any issues related to handling or winding stresses. The windings are of the disk or layered conductor type, and the coils and gap between them and between the layers are positioned according to precise electrical design criteria, as is the choice of conductor type and how it is processed.
The winding drying and pressing process prior to assembly is fundamental. This stage takes place in a furnace with dry air circulation and controlled, monitored temperatures. Power transformers can have two or more windings, and can be fitted with compensator windings.
Power
6.3 MVA to 50 MVA
Voltage class
up to 145 kV (BIL 650)
Windings
aluminium or copper
Cooling
ONAN, ONAF, KNAN or OFWF
Oil type
mineral, Midel 7131, vegetable, silicone
Switching
no-load, on-load (OLTC)
Ambient temperature
-60°C to +60°C
Accessories
Overpressure valve, thermometer, oil level, Buchholz relay, protective casing and more
Strong points
Outdoor installation even in aggressive environmental conditions; no insulation level limits, excellent resistance to resonant overvoltages
