Interested to Buy Any Domain ? << Click Here >> for more details...
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.
- 9 Answers
- 20959 Views
- I also Faced
- E-Mail Answers
Answer Posted / sudheer
please check the OLTC inside
connections ,carefully .because some times the connector
plate rollers not touch properly. so the winding temp.
increases continuously and oil will over-heated.
| Is This Answer Correct ? | 1 Yes | 3 No |
Post New Answer View All Answers
how open delta PT works & what is its construction?
HOW CAN I GET 5CORE HO7 CABLE SIZE IF I HAVE 1800A?
what is the function of anti pumping relays? what is KVAR? How it is generated in alternator? What is 3rd Harmonics? What is IDMT relay?
what is the effect of connecting three phase supply lines to three phase auto transformer output terminals through a fuse of 10Amp and a circuit breaker (MCB). Is this connection permanently destroy the transformer?
How can claculate to attain the desired PF in the line ( HOW Much KVAR is required ) Pls Give the formula? Equate Petrochemical 0 1 how to calculate sizing of NGTR (Transformer rating,Loading resistor value and Current rating of resistor) and what is the X/R ratio. Details : 11kV,Capacitance 1.73532 micro farads,40kA for 1sec. 0 1 What will happened. if we feed 3phase supplay to the stater with out insert the rotor. How much current will flow through the stater winnding? Equate Petrochemical 0 1 What is required of exietation to the alternater. 0 1 why star point of HT motor not earthed? Equate Petrochemical 0 1 Why we are getting low voltage in star connection? Equate Petrochemical 0 2 What's ND relay & it's functions? Equate Petrochemical 0 2 How instantanious short circuit current is calculated? its formula? Equate Petrochemical 0 2 What is servo Motor? What's the advantages of this motor over Induction motor? Equate Petrochemical 0 2 What is core CT & it's function? Equate Petrochemical 0 3 what is meant by star/delta voltages as 440/220 in a 3 phase induction motor, and why it should be connected on STAR IN 3 PHASE SUPPLY L & T 0 4 What is required of exietation to the alternater. KNB 1 23 what is the design voltage for 6.6KV 2000 KVAR HT capacitor? Consultancy 0 3 Pls explain about vfd control?Where it is used, Give some example? siemens 1 22 Please explain me abt PQ diagaram in the power sector. 0 9
please give some hindalco placement papers for written exam
Explain few advantages of electric traction system?
Work done in a free expansion process is
hello!my name is sheikh iam preparing for indian engineering servieces,please send me the old question papers..to sheikhshaazforjobs@gmail.com
What are the relays in ACB and VCB
What is cathode ray oscilloscope (cro)?
why ct's&pt'S out put called as burden,why compelsary short ckt the secondary of ct's while removing the burden?
What is power in wattage of 8.5 TR AC
why did youi choose this career?
can any one suggest paper presentation topies for electrical engg?
