DAHAI POWER SDN BHD
No. G-1-2, Lot 49, 1st Floor, Block G, Sulaman Sentral, METHOD OF STATEMENT
P.O. BOX 42, 88450 Menggatal, Kota Kinabalu, Sabah, Malaysia
Tel: 088-489586 Fax: 088-489585 Email: dahytek@yahoo.com
AVR PARALLEL SCHEME
Customer SABAH ELECTRICITY SDN BHD Contractor SUN SYSTEM ENGINEERING SDN. BHD.
Site PPU PIRASAN 33/11kV Bay RTCC1 & RTCC2
A. Finding for Parallel Scheme (RTC1 & RTC2)
1. Setting for the both AVR for parallel operation as follow:
Description RTC1 RTC2
Parallel Control Circulating current Circulating current
SKB parallel operation OFF OFF
Can Address 1 2
Stability 40% 40%
Blocking 20% 20%
Alarm 10 sec 10 sec
Tapping direction Standard Standard
2. Topology for both AVR had been set with T1 & T2 will be paralleled if Incomer 1, Incomer 2 and 11kV
Bus Section’s CB closed. Simulation as in table in below:
Incomer 1’s CB Incomer 2’s CB Bus Section’s CB Parallel operation
Closed Closed Closed Parallel OK
Opened Closed Closed Not in parallel
Closed Opened Closed Not in parallel
Closed Closed Opened Not in parallel
3. Problem found during testing is, during all the incomer 1, incomer 2 and bus section’s CB status in
closed position, ‘Parallel failure’ alarm will be triggered to the annunciator and cannot be reset.
4. Stability for both AVR had been set to 40% and found that the bandwidth during 2 tap position
difference for both transformers greater than bandwidth setting, as in table below:
Tap position Bandwidth (%)
Transformer No. 1 Transformer No. 2 Transformer No. 1 Transformer No. 2
5 7 +1.7% -1.71%
5. Setting for bandwidth percent is 1.67%
6. Even though the AVR already detected the bandwidth greater than the bandwidth setting, timing for
changing the tap position in AUTO mode did not start due to parallel failure.
7. Stability setting had been varied from 0% to 40% but still the parallel failure alarm cannot be reset.
8. Blocking setting also had been varied from 20% to 0% but still the parallel failure alarm cannot be
reset.
DAHAI POWER SDN BHD
No. G-1-2, Lot 49, 1st Floor, Block G, Sulaman Sentral, METHOD OF STATEMENT
P.O. BOX 42, 88450 Menggatal, Kota Kinabalu, Sabah, Malaysia
Tel: 088-489586 Fax: 088-489585 Email: dahytek@yahoo.com
AVR PARALLEL SCHEME
Customer SABAH ELECTRICITY SDN BHD Contractor SUN SYSTEM ENGINEERING SDN. BHD.
Site PPU PIRASAN 33/11kV Bay RTCC1 & RTCC2
Parallel Fail Alarm during CB status Incomer 1, Incomer 2 and Bus Section in closed position
Message at AVR’s info during both transformer in parallel
DAHAI POWER SDN BHD
No. G-1-2, Lot 49, 1st Floor, Block G, Sulaman Sentral, METHOD OF STATEMENT
P.O. BOX 42, 88450 Menggatal, Kota Kinabalu, Sabah, Malaysia
Tel: 088-489586 Fax: 088-489585 Email: dahytek@yahoo.com
AVR PARALLEL SCHEME
Customer SABAH ELECTRICITY SDN BHD Contractor SUN SYSTEM ENGINEERING SDN. BHD.
Site PPU PIRASAN 33/11kV Bay RTCC1 & RTCC2
Info at AVR in TOPOLOGY during parallel mode
UC2 card input status
DAHAI POWER SDN BHD
No. G-1-2, Lot 49, 1st Floor, Block G, Sulaman Sentral, METHOD OF STATEMENT
P.O. BOX 42, 88450 Menggatal, Kota Kinabalu, Sabah, Malaysia
Tel: 088-489586 Fax: 088-489585 Email: dahytek@yahoo.com
AVR PARALLEL SCHEME
Customer SABAH ELECTRICITY SDN BHD Contractor SUN SYSTEM ENGINEERING SDN. BHD.
Site PPU PIRASAN 33/11kV Bay RTCC1 & RTCC2
Serial Number AVR T1
Serial Number AVR T2
DAHAI POWER SDN BHD
No. G-1-2, Lot 49, 1st Floor, Block G, Sulaman Sentral, METHOD OF STATEMENT
P.O. BOX 42, 88450 Menggatal, Kota Kinabalu, Sabah, Malaysia
Tel: 088-489586 Fax: 088-489585 Email: dahytek@yahoo.com
AVR PARALLEL SCHEME
Customer SABAH ELECTRICITY SDN BHD Contractor SUN SYSTEM ENGINEERING SDN. BHD.
Site PPU PIRASAN 33/11kV Bay RTCC1 & RTCC2
UC2 input as in schematic drawing
Info in AVR during transformer in parallel (Voltage, load current, reactive current and tap positon)
