Transformer 10 MVA 22kV/6.9kV has been shutdown.
Transformer 10 MVA 22kV/6.9kV has been shutdown.
(OP)
Transformer 10 MVA 22kV/6.9kV has been shutdown.
- Bucholz device activated
- Pressure Relife Device activated
and too much oil spill to outside of transformer from pressure relife device.
After incident ,We have checked
Insulation of winding and Earth = 0 Mohm
Insulation of HV and LV winding = 0 Mohm
-Downstream (6.6 kV SWG)
Differential and Buchholz trip
-Upstream (22 kV SWG)
intertriping trip and Earth Fault
So anyone can suggest what problem happen with my transformer ?
and what can i do ?
Thanks you
- Bucholz device activated
- Pressure Relife Device activated
and too much oil spill to outside of transformer from pressure relife device.
After incident ,We have checked
Insulation of winding and Earth = 0 Mohm
Insulation of HV and LV winding = 0 Mohm
-Downstream (6.6 kV SWG)
Differential and Buchholz trip
-Upstream (22 kV SWG)
intertriping trip and Earth Fault
So anyone can suggest what problem happen with my transformer ?
and what can i do ?
Thanks you






RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
If you're lucky, it only needs a rewind.
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
dpc has it correct. Your transformer has died. It sounds like interwinding and winding to ground failures. this is serious stuff.
There is only a tiny possibility that repairs will be simple. 99% chance it will have to go away for repairs.
It is likely that your oil sample when analyzed for dissolved gases will show products that indicate high intensity discharge within the oil.
The fact that BOTH windings show zero ohms to ground discounts the possibility of an easy fix like a bad bushing that could be replaced on site.
old field guy
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
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If we learn from our mistakes I'm getting a great education!
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
Most of the reliefs I'm used to seeing seat off (mostly) after dumping the pressure. I think a DGA would still be good. However, if the oil was exposed to atmosphere for very long, it would be less so.
A sample might also show suspended carbon and other products of the fault.
old field guy
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
----------------------------------
If we learn from our mistakes I'm getting a great education!
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
I have checked the record from digital relay.
T observed that phase B loose of the current in that fault time and high rush current in another 2 phases.
I plan to sent it to manufactere soonest.
Young Engineer.
RE: Transformer 10 MVA 22kV/6.9kV has been shutdown.
If you get a chance, follow the transformer back to the factory and view the work. It's good experience.
Good luck!
old field guy