On load tap changer (OLTC) explode?
Transformer
Vector group: Ynd11
Rated Power: 353MVA
Rated Current: 693A
Voltage:294/20KV
OLTC
Type: T III Y1000 110/c 12193w
Max Operation Current: 295A
Step Voltage: 550V
Arrangement in Tx windings: Y Connection
Problem: Damage of Unit 1 Generator Transformer On Load Tap
Changer (OLTC)
Description of Incident:
9.00 a.m. :- Generator No Load test on excitation system
started
10.30 a.m :- Carried out AVR change over
test
11.30 a.m :- Preparation for Generator Manual Synchronizing
test
12.00 a.m :- Manual Synshronizing test started.
Observed incoming generator voltage higher than running voltage.
CECR operator operated Generator Transformer OLTC to bring down
the incoming generator voltage
12.03 a.m :-Generator Transformer abnormal alarm operated at
Gen.Control Desk (CECR)
CECR operater at Generator transformer bay informed that the
transformer
oil splashed out from OLTC.
CECR operater informed that he heard explosion inside OLTC.
Observed Oil level & Oil Flow alaram operated at Tranformer
local annunciator.
12.05 am :- CECR operator 'Open Gen Field Breaker”
12.10 a.m. :- Elec1 team inspected the OLTC and found the
OLTC rupture disk was broken
and oil spilled at OLTC area.
- Elec1 found the OLTC top cover bulging.
Do anyone know why and possibility cause happen in this OLTC.
Answer Posted / j.kesavan
oltc always problem,why its opration is motorised in auto
cotrol ,thats why disc breake every time
Is This Answer Correct ? | 3 Yes | 5 No |
Post New Answer View All Answers
What is value of earth resistance required for substation and equipment earthing and what are the reference guidelines
What is Icu and Ics and what is difference b/w them. please tell me how to calculate a size of a copper bar for a system or a breaker... reply on... king.arish@gmail.com would be waiting for a logical answer.
how can i determine the KVA/MVA rating of transformer precisely?? is there any standard test?????
I have a CT meter with ratio 60/5. The meter reading of previous month was 3290.49 and that of current month was 3797.26. How many chargeable units as per normal meter should be my reading.
what is the difference between c power and U power acb breaker
i wasted one year for the job after completed my btech what can i say about 1year time in interview
full form of electrical?
Refernce currents are to be generated using refernce cueernts how can this be done
What are the advantages of hydropower?
Diagram on interconnectivity of 11kv transformer with RMU (i.e, one incoming and two outgoing or two incoming and one outgoing)
hi i have applied for lic of india south cenrtal zonal ,hyd. i didnt get hall ticket till now.let me know how can i get form internet
condition Autotrip facia come on control panel of electrical transmission line?
What is the function of auadag in a cro?
what is mean by D.O. in distribution line poles?
what are the maximum available current, voltage ratings and switching speeds of the power electronic devices thyristor, power mosfet, igbt, and mct?