CP TD1 Reference Manual V 1.44
68
Transformer Faults
Table 6-3 Transformer Faults [3.3]
Fault Examples
Partial discharges Discharges in gas-filled cavities in insulation,
resulting from incomplete impregnation, high
moisture in paper, gas in oil supersaturation
or cavitation (gas bubbles in oil), leading to X
wax formation on paper.
Discharge of low energy Sparking or arcing between bad connections
of different floating potential, from shielding
rings, toroids, adjacent discs or conductors of
different windings, broken brazing, closed
loops in the core. Additional core grounds.
Discharges between clamping parts, bushing
and tank, high voltage and ground, within
windings. Tracking in wood blocks, glue of
insulating beam, winding spacers. Dielectric
breakdown of oil, load tap changer breaking
contact.
Discharge of high energy Flashover, tracking or arcing of high local
energy or with power follow-through. Short
circuits between low voltage and ground,
connectors, windings, bushings and tank,
windings and core, copper bus and tank, in oil
duct. Closed loops between two adjacent
conductors around the main magnetic flux,
insulated bolts of core, metal rings holding
core legs.
Overheating less than 300°C Overloading the transformer in emergency
situations. Blocked or restricted oil flow in
windings. Other cooling problem, pumps
valves, etc. Stray flux in damping beams of
yoke.
To Next Page
Loading...
Need help?
General
