BNERI
Reliability Indices
Measurement Reliability Indices Measurement for three 11 kV
and 66 kV substations in Brunei Darussalam
(PWR 01)
NUR SABIQAH HAJI ROSLI
Draft dated 27th May 2015 i
ACKNOWLEDGEMENT
I would like to express my deepest appreciation to all those who provided me the possibility to complete
this report. I would also like to acknowledge with much appreciation the crucial role of Robinson Goh,
Hajah Zuriyati and Haziqah Nordin, the staff of Department of Electrical Services in the Distribution
Department, who provided their power outages and Single Line Network data to complete this Reliability
Indices Measurement project.
A special gratitude I give to our supervisor, Chief Researcher of Power Department, Dr. Arvind K S
Chaudhary, whose contribution in stimulating suggestions and words of encouragement helped me to
coordinate this project especially in writing this report.
Draft dated 27th May 2015 ii
EXECUTIVE SUMMARY
One of the Key Performance Indicators (KPI) under the Energy White Paper 2014 is to reduce the number
of power outages by 2035, which is in line with Wawasan 2035. Therefore, quantitative reliability
indices measurement such as System Average Interruption Duration Index (SAIDI) and System Average
Interruption Frequency Index (SAIFI) has been calculated for three 11 kV and 66 kV substations in
Brunei Darussalam.
In this study, IEEE Guide for Electric Power Distribution Reliability Indices (IEEE Std 1366-2012) is
used as the methodology and only unplanned and sustained interruptions are taken into account to provide
consistency in all four districts, to review and improve current reliability and performance of distribution
system in Brunei Darussalam. To further improve the performance of distribution system, design and
implementation of Smart Grid technologies can be utilized in Brunei Darussalam
Draft dated 27th May 2015 iii
Table of Contents
ACKNOWLEDGEMENT ............................................................................................................................. i
EXECUTIVE SUMMARY .......................................................................................................................... ii
1. INTRODUCTION .................................................................................................................................... 1
1.1 Scope of Work .................................................................................................................................... 1
2. ACRONYMS ............................................................................................................................................ 2
3. GLOSSARY ............................................................................................................................................. 3
4. POWER SYSTEM RELIABILITY .......................................................................................................... 4
4.1 Background ......................................................................................................................................... 4
4.2 SYSTEM AVERAGE INTERRUPTION DURATION INDEX (SAIDI) ......................................... 5
4.4 Distribution System ............................................................................................................................ 8
5. METHODOLOGY IEEE GUIDE ............................................................................................................ 9
5.1 Factors that cause variation in reported indices .................................................................................. 9
5.2 Outages that should not be taken into account when calculating indices ......................................... 10
5.3 Example of using MED definition to identify Major Event. ............................................................ 10
5.4 Sample System to calculate SAIDI and SAIFI with no MED .......................................................... 11
5.5 Catastrophic Days ............................................................................................................................. 12
5.6 List of data requested from DES for both 11 kV and 66 kV substations .......................................... 13
6. SYSTEM RELIABILITY CALCULATION FOR BRUNEI DARUSSALAM. .................................... 14
6.1 Step Restoration ................................................................................................................................ 14
6.2 Analysis of three 11 kV substations in Brunei Darussalam .............................................................. 17
6.2.1 SAIDI calculation for 11 kV substations ............................................................................ 18
6.2.2 SAIFI calculation for 11 kV substations ............................................................................. 22
6.3 Analysis of three 66 kV substations in Brunei Darussalam. ........................................................... 23
6.3.1 SAIDI calculation for 66 kV substations ................................................................................... 23
6.3.2 SAIFI ................................................................................................................................... 28
7. POWER OUTAGE ................................................................................................................................. 29
7.1 Causes of power outages. .................................................................................................................. 29
7.1.1 Weather related power outages. ..................................................................................................... 29
7.1.2 Faulty Equipment ........................................................................................................................... 30
7.1.3 Overcurrent .................................................................................................................................... 30
7.1.4 Flashover transformer .................................................................................................................... 30
7.1.5 Animal Contacts ............................................................................................................................. 30
7.1.6 People induced including: pole and overhead contacts and underground digging ........................ 30
Draft dated 27th May 2015 iv
7.1.7 Short Circuit ................................................................................................................................... 30
7.1.8 Electrical Trees ....................................................................................................................... 30
7.2 Examples of power outages (historical blackouts). ..................................................................... 31
8. CONCLUSION ....................................................................................................................................... 32
9. FUTURE WORK .................................................................................................................................... 33
References ................................................................................................................................................... 34
Appendix ...................................................................................................................................................... A
Appendix 1: Power Outages for 2014 and 2013 ...................................................................................... A
Appendix 2: List of required data for accurate calculation of SAIDI and SAIFI ................................... W
Draft dated 27th May 2015 1 of 34
1. INTRODUCTION
More than half of Brunei Darussalam’s revenue comes from the energy sector. The Energy White paper
has outlined three strategic goals to realize Brunei Darussalam’s energy vision. One of the Key
Performance Indicator (KPI) is to reduce the number of power outages by 2035, in line with the goals of
Wawasan 2035 [1].
The main aim of this project is to provide electric power distribution reliability indices, namely System
Average Interruption Duration Index (SAIDI) and System Average Interruption Frequency Index (SAIFI),
to benchmark DES (Department of Electrical Services) and chart improvements used in all utilities
worldwide. As well as to identify root causes of power outages in Brunei Darussalam.
The reliability indices of electric power distribution will follow a set of methodology outlined in IEEE
Guide for Electric Power Distribution Reliability Indices [2] to ensure the indices obtained are consistent
with best practices in the Power Industry.
1.1 Scope of Work
Understand existing distribution equipment and protection philosophy. This includes the
understanding of IEEE Std. 1366-2012 methodology (and other standards Department of
Electrical Services (DES) used) and consultation from DES personnel.
Gather information from DES. Conduct survey at a few substations and their feeders. Create and
understand scenarios given by DES.
Obtain and analyze the data given to calculate SAIDI (in minutes) and SAIFI.
Compare the results obtained for SAIDI and SAIFI with DES.
Write report on SAIDI and SAIFI results and peer review.
Execution plan (Gantt chart) is attached at the back of this report.
Draft dated 27th May 2015 2 of 34
2. ACRONYMS
SAIDI System Average Interruption Duration Index
SAIFI System Average Interruption Frequency Index
DES Department of Electrical Services
MIS Main Intake Station
Draft dated 27th May 2015 3 of 34
3. GLOSSARY
Customer A metered electrical service point for which
an active bill account is established at a
specific location.
Interruption The total loss of electric power on one or
more normally energy conductors to one or
more customers connected to the distribution
portion of the system.
Interruption Duration The time period from the initiation of an
interruption until service has been
restored to the affected customers.
Major Event An event that exceeds the reasonable design
and or operational limits of the electric
power system.
Major Event Day (MED) A day where the daily SAIDI index exceeds
a Major Event Day (MED) threshold value.
Interruptions which occur on MED should
be separately analyzed.
Momentary Interruption The brief loss of power delivery to one or
more customers caused by opening and
closing operation of an interrupting device.
Usually less than 5 minutes.
Outage The loss of ability of a component to deliver
power.
Planned Interruption The loss of electric power to one or more
customers that results from a planned
outage.
Reporting period The time period from which interruption
data is to be included in the reliability index
calculations.
Sustained Interruption Any interruption not classified as a part of a
momentary event. Interruption which lasts
more than 5 minutes.
Total number of customers served The average number of customers served
during the reporting period. If a different
customer total is used, it must be clearly
defined in the report.
Draft dated 27th May 2015 4 of 34
4. POWER SYSTEM RELIABILITY
4.1 Background Electric power system is one of the most important and complex systems created by human. It comprises
countless facilities and structures, systems and subsystems, components and equipments and interactions
between all [3]. It was also reported that more than 50% of reliability depends on the performance of
distribution system [3]
Electric power has become an essential part of humans’ lives up to an extent that it is impossible to live
without electrical power. This stresses the importance of power system reliability. Reliability of power
system is mainly concerned with customer interruptions, thus, it is a subset of power quality [4].
In this report, two main power system reliability indices are looked into, particularly SAIDI (System
Average Interruption Duration Index) and SAIFI (System Average Interruption Frequency Index).
Additional index such as CAIDI (Customer Average Interruption Duration Index) can also be derived
from the initial indices.
There are mainly two main types of interruptions, sustained and momentary. Where sustained interruption
is closely related to reliability issue (more than five minutes), and momentary interruptions as power
quality issue (usually less than five minutes) [2,4].
Figure 1: shows Power Quality Subset [4]
Draft dated 27th May 2015 5 of 34
4.2 SYSTEM AVERAGE INTERRUPTION DURATION INDEX (SAIDI)
The System Average Interruption Duration Index (SAIDI) indicates the sum duration of interruption for
the average customer during a predefined set of time [2]. The unit used to measure SAIDI is in minutes
or hours of interruption. The equation used to measure SAIDI is given in Eq. (1)[2].
ServedCustomersofNumberTotal
onInterruptiofMinutesCustomerSAIDI
(1)
To calculate the index, Eq (2) can be used, where ri is restoration time for each interruption event, Ni
stands for number of interrupted customers for each sustained interruption event during a reporting
period, NT is total number of customers served for the area and CMI stands for customer minutes of
interruption [2].
TT
ii
N
CMI
N
NrSAIDI
(2)
Figure 2 shows Unplanned SAIDI for various countries, including exceptional event [5].
Draft dated 27th May 2015 6 of 34
Figure 3 shows Unplanned SAIDI for various countries, excluding exceptional events [5]
From Figures 2 and 3, it can be observed that due to the elimination of exceptional events, the SAIDI
decreases.
Draft dated 27th May 2015 7 of 34
4.3 SYSTEM AVERAGE INTERRUPTION FREQUENCY INDEX (SAIFI)
The System Average Interruption Frequency Index (SAIFI) shows how frequently the average customer
experiences a sustained interruption over a predefined period of time. The equation used to calculate
SAIFI is (Eq 3) [2].
ServedCustomersofNumberTotal
dInterrupteCustomersofNumberTotalSAIFI
(3)
To calculate the index, Eq (4) can be used. Where CI is customers interrupted [2],
TT
i
N
CI
N
NSAIFI
(4)
Figure 4 shows Unplanned SAIFI for various countries, including exceptional event [5].
Draft dated 27th May 2015 8 of 34
Figure 5 shows Unplanned SAIFI for various countries, including exceptional event [5].
4.4 Distribution System
The distribution system is the final stage in delivering electrical power to consumers. An ordinary
distribution system consists of step – down transformer with various lengths (a few hundred meters to
several kilometers), so the voltage can be stepped down to distributed levels for industrial, commercial
and residential users [9].
Draft dated 27th May 2015 9 of 34
5. METHODOLOGY IEEE GUIDE In order to accurately develop indices of a power system reliability measurement, IEEE Std 1366-2012
was used as a methodology, so as to obtain consistent results amongst utilities in the region.
A Major Event Day (MED) is an identified day in which the daily system SAIDI exceeds a threshold
value called TMED. Thus, the SAIDI index obtained will be consistent regardless of size of utility and any
anomaly (MED value) which may lead to a higher SAIDI value is analyzed separately and removed from
indices calculation.
A TMED value is typically obtained at the end of each reporting period (one year) for use during the next
reporting period as follows [2]:
Obtain daily SAIDI values for five years, which ends on the final day of the last entire reporting
period.
Only include days which have SAIDI/day value which can contribute in calculation of TMED, i.e
exclude days where interruptions did not occur.
Take the natural log of each daily SAIDI value in the data set
Find alpha, the average of the log of the data set
Find Beta, the standard deviation of the log of the data set.
Compute the MED threshold, using Eq. (5) [2]
)5.2( eTMED (5)
Any day with daily SAIDI greater than the threshold value Tmed that occurs during the subsequent
reporting period is classified as MED.
5.1 Factors that cause variation in reported indices There are various factors that can cause difference in the indices reported by different utilities. Some
examples are in [2];
Level of automated data collection
Geography
System design
Data classification
Draft dated 27th May 2015 10 of 34
It is highly essential to classify performance for each day in the data set to be analyzed as either day-to-
day or MED; false decision may occur when this important step is not performed, as MED may disguise
overall daily performance.
5.2 Outages that should not be taken into account when calculating indices
There are several types of outages that should not be included when calculating the indices, such as [2]:
Interruptions that occur as a result of outage on customer – owned facilities
Loss of supply from another utility
Planned interruptions
Momentary interruptions
These interruptions are not included in calculation of SAIDI and SAIFI as to provide uniform and
consistent policy in all four districts. Furthermore, the calculation is done to review and improve current
performance of unplanned events.
5.3 Example of using MED definition to identify Major Event.
The following example shows the calculation of
Daily SAIDI
MED threshold, TMED
Identification of MEDs and calculation of adjusted indices.
Table 1 shows selected data for all interruptions which occur on a certain day for a utility which serves
2000 customers
DATE TIME DURATION
(MIN)
NUMBER OF
CUSTOMERS
INTERRUPTION
TYPE
July 15, 1995
18:34:30 20.0 200 Sustained
July 15, 1995
18:38:30 1.0 700 Momentary
July 15, 1995
18:42:00 513.5 400 Sustained
Table 1 shows Interruption data for July 15, 1995.
Draft dated 27th May 2015 11 of 34
For July 15, 1995, daily SAIDI (assumption: a 2000 customer utility) is given in Eq (6):
min7.1042000
)4005.513()20020(
SAIDI
5.4 Sample System to calculate SAIDI and SAIFI with no MED
Table 2 below shows an extract from one utility’s customer information system (CIS) database for feeder
7055 [2], which serve 2000 customers with a total load of 4MW. In this sample system, Circuit 7055 is a
representation for the “system” where the indices are to be calculated. Furthermore, the “system” consists
of all the circuits together in a region for a whole company.
Date Time off Time on Circuit Number of
Customers
Duration
(min) Load kVA
Interruption
type
Jan 17 121220 12:20:30 7055 200 8.17 800 S
Feb 15 18:23:56 18:24:26 7055 400 0.5 1600 M
Mar 13 00:23:10 01:34:29 7055 600 71.3 75 S
Apr 24 23:17:00 23:47:14 7055 25 30.3 4000 S
May 27 09:30:10 09:31:10 7055 2000 1.0 500 M
June 22 15:45:39 20:12:50 7055 90 267.2 2100 S
July 19 08:20:00 10:20:00 7055 700 120 1800 S
Aug 31 17:10:00 17:20:00 7055 1500 10 3000 S
Sep 3 10:15:00 10:55:00 7055 100 40 200 S
Table 2: An example of interruption data for a utility
Note: S – Sustained Interruption, M – Momentary Interruption
Equations (2) and (3) should be used to calculate the annual indices, using the data shown in Table 2,
assuming there were no MEDs in the data.
min11.862000
)10040()150010()700120()902.267()253.30()6003.71()20017.8(
SAIDI
61.12000
10015007009025600200
SAIFI
Draft dated 27th May 2015 12 of 34
5.5 Catastrophic Days
It is assumed that, when calculating the daily SAIDI and the 2.5β method, the distribution of the natural
log values will look like a Gaussian distribution (a bell-shaped curve) [2]. Events such as hurricanes or ice
storms typically result in abnormally higher daily SAIDI values, and these events are called “catastrophic
events”, and have a slim probability of happening [2].
It is typical for catastrophic event, which leads to higher SAIDI values to exist in data sets and this will
cause relatively small outward shift in the resulting reliability metric trends [2]. Thus, measures have been
taken to identify and process catastrophic, in order to remove the effect it has on reliability metric trends
[2].
Furthermore, when catastrophic events are not taken into account, this may cause a huge increase in the
events identified as MEDs. It was also proposed that catastrophic events should be processed and
determined on an individual company basis by regulators and utilities itself, as no universal solution has
been devised to achieve acceptable results [2].
Draft dated 27th May 2015 13 of 34
5.6 List of data requested from DES for both 11 kV and 66 kV substations 2013 2014
Data Requested
Mentiri
Substation
Beribi
Substation
Kuala
Belait
Substation
Mentiri
Substation
Beribi
Substation
Kuala
Belait
Substation
Date of power
outage
Duration of power
outage
Number of
customers
interrupted
Number of
customers served
Step restoration
information
Stages
required to
restore
power
Duration to
restore
power at
each stage
Number of
customers
restored at
each stage
Causes of outage
Draft dated 27th May 2015 14 of 34
6. SYSTEM RELIABILITY CALCULATION FOR BRUNEI
DARUSSALAM.
6.1 Step Restoration When power outages occur, power is not always fully restored in one stage, but, it takes a series of stages
to restore power to all interrupted customers, this process is called step restoration. A sample calculation
is shown below to illustrate how SAIDI is calculated when step restoration takes place. It is also
important to know the duration of outages during restoration and number of customers restored at a
particular restoration time to accurately calculate SAIDI.
Figure 6: Single line network representation
Draft dated 27th May 2015 15 of 34
Figure 6 shows a representation of single line network. A sample case of step restoration can be broken
down into a few steps as follow:
When a fault occurs at X, Breaker number 1 opens and isolates the fault. Operation on Breaker
number 1 also opens the load break switch (LBS) of substations A, B, C and D. At this point,
outage of power occurs at A, B, C and D
Operator is sent to site to locate the Fault Circuit Indicator (FCI) which identifies the fault
location path.
1. LBS at A1 is closed to restore partial power. Since load at substation A is restored, then
A2 is closed.
2. Operator arrives at substation B, checks the FCI and closes LBS B1 to restore partial
power. Since the load at substation B1 is restored, then B2 is closed.
3. Operator arrives at substation C, checks the FCI and closes LBS C1 to restore partial
power. Since the load at substation C1 is restored, then C2 is closed.
4. Operator arrives at substation D, checks the FCI and closes LBS D1 to restore partial
power. Since the load at substation D1 is restored, and then D2 is closed but due to the
presence of fault, power is not restored back to the affected customers, and fault is
detected. This fault is then isolated and reported by operator.
Permanent repairs are completed, and power to all customers is restored. The outage event is
concluded.
One example of step restoration took place in Kuala Belait on the 28th of March 2014; the number of
customers restored at each restoration was not known in detail. Thus, percentages of customers restored
are used to illustrate how the amount of customers initially restored affects the SAIDI value.
Three sample cases are tabulated to calculate SAIDI where the percentages of customers restored are
varied.
The three sample cases are:
In Table 4: Equal number of customers is restored in four separate restoration times (25%).
In Table 5: More customers are restored in the first 20 minutes (75%)
In Table 6: Remaining 75% of customers restored after 80 minutes.
Scenario orders numbered 1-4, in Tables 4, 5 and 6 represent the steps (stages) taken to close each LBS
(A B, C and D – refer to Figure 6), locate the fault and restore power back to interrupted customers
Draft dated 27th May 2015 16 of 34
Scenario
Order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time
off
Time
on
Interruption
duration
(min)
Customers
interrupted
(CI)
Customer minutes
of
interruption(CMI)
- 0% 0 3144 - -
1 25% 786 2358 12:00 12:20 20 786 15720
2 25% 786 1572 12:00 12:40 40 786 31440
3 25% 786 786 12:00 1:00 60 786 47160
4 25% 786 0 12:00 1:20 80 786 62880
100% 3144 - - - - 3144 157200
SAIDI in
mins
50
Table 4: Sample step restoration with equal number of customers at each stage
Scenario
Order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time
off
Time
on
Interruption
duration
(min)
Customers
interrupted
(CI)
Customer minutes
of
interruption(CMI)
- 0% 0 3144 - -
1 75% 2358 786 12:00 12:20 20 2358 47160
2 10% 314 471 12:00 12:40 40 314 12576
3 10% 314 157 12:00 1:00 60 314 18864
4 5% 157 0 12:00 1:20 80 157 12576
100% 3144 - - - - 3144 91176
SAIDI in
mins
29
Table 5: Sample step restoration where 75% of customers are restored in the first 20 minutes
Draft dated 27th May 2015 17 of 34
Scenario
Order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time
off
Time
on
Interruption
duration
(min)
Customers
interrupted
(CI)
Customer minutes
of
interruption(CMI)
- 0% 0 3144 - -
1 5% 157 2987 12:00 12:20 20 157 3144
2 10% 314 2672 12:00 12:40 40 314 12576
3 10% 314 2358 12:00 1:00 60 314 18864
4 75% 2358 0 12:00 1:20 80 2358 188640
100% 3144 - - - - 3144 223224
SAIDI in
mins
71
Table 6: Sample step restoration where 75% of customers are restored in the last 20 minutes
From the SAIDI values obtained from Table (4), Table (5) and Table (6) above, it can be observed that
SAIDI value is smaller when the first batch of customers restored are higher (29 mins from Table 5).
Meanwhile, when the remaining 75% of customers are restored after 80 minutes, the SAIDI value
increases to 71 minutes and when equal number of customers restored takes place at each restoration
time, the value of SAIDI lies in between 71 and 29 minutes, that is 50 minutes.
In conclusion, when the distribution of customers restored and the number of customers restored at each
restoration time are not known, it can be seen that, the SAIDI value lies more towards the time when the
largest number of customers are restored at.
6.2 Analysis of three 11 kV substations in Brunei Darussalam
To carry out the calculation to estimate the SAIDI and SAIFI for Brunei Darussalam, three 11 kV
substations have been analyzed, which are:
Kuala Belait Substation
Mentiri Substation
Beribi Substation
Draft dated 27th May 2015 18 of 34
6.2.1 SAIDI calculation for 11 kV substations To develop the estimates of SAIDI for the three 11 kV substations, a few parameters were looked into in
the power outages data provided by DES (Appendix 2), as mentioned in previous chapter (Chapter 5).
The parameters are:
If restoration of power occur in full or in steps (step restoration)
If Major Event Day (MED) is involved (outage which will increase the SAIDI value – typically
due to natural disasters where outages can last for days)
A few step restoration scenarios were identified in Kuala Belait outages in year 2014 and 2013 (no step
restoration identified in Beribi and Mentiri). The identified step restoration outages are highlighted in
Appendix 2. Further breakdown on calculation of SAIDI for step restoration is laid out below (Tables 7-
11). The calculation of SAIDI which involves step restoration cannot be done accurately as the number of
customers restored at a particular restoration time is not known in detail.
Moreover, due to unavailability of five historical years of data, calculation of MED threshold, as per
reference from IEEE Std 1366-2012 [2] cannot be performed. Thus, in this calculation, it is assumed that
equal number of customers are restored at each restoration time.
KB outage on 22/06/2013
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 50 - - - -
1 50% 25 25 7:00 AM 9:40 AM 160 25.00 4000
2 50% 25 0 7:00 AM 10:45
AM 225 25.00 5625
TOTAL 100% 50 - - - - 50.00 9625
Table 7: Step restoration calculation for power outage in KB on 22/06/2013
Draft dated 27th May 2015 19 of 34
KB outage 03/08/2013
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 3309 - - - -
1 50% 1655 1655 11:30 AM 4:00 PM 270 1655 446715
2 50% 1655 0.00 11:30 AM 10:00
PM 630 1654.50 1042335
TOTAL 100% 3309 - - - - 3309.00 1489050
Table 8: Step restoration calculation for power outage in KB on 03/08/2013
KB Outage 20/01/2014
Scenario
order
% of
customer
s
restored
Customers
restored
Customers
remaining
interrupte
d
Time off Time
on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 8867 - - - -
1 33% 2956 5911 6:20 PM 7:03 PM 43 2956 127093
2 33% 2956 2955 6:20 PM 8:55 PM 155 2956 458127
3 33% 2955 0.00 6:20 PM 10:40
PM 260 2955 768471
TOTAL 100% 8867 - - - - 8867 1353692
Table 9: Step restoration calculation for power outage in KB on 20/01/2014
KB Outage 11/05/2014
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 4445 - - - -
1 50% 2223 2222 12:15
PM 5:00 PM 285 2223 633412
2 50% 2222 0.00 12:15
PM 5:25 PM 310 2222 688975
TOTAL 100% 4445 - - - - 4445 1322387
Table 10: Step restoration calculation for power outage in KB on 11/05/2014
Draft dated 27th May 2015 20 of 34
KB Outage 28/05/14
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time
on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 3144 - - - -
1 33% 1048 2096 11:37 AM 1:15 PM 98 1048 102703
2 33% 1048 1048 11:37 AM 5:15 PM 338 1048 354224
3 33% 1048 0.00 11:37 AM 6:00 PM 383 1048 401384
TOTAL 100% 3144 - - - - 3144 858311
Table 11: Step restoration calculation for power outage in KB on 28/05/2014
To calculate the SAIDI values for Kuala Belait, Mentiri and Beribi; the number of customers served at
each is defined in Table 10, this information is obtained from DES.
Venue Number of customers served Description
Kuala Belait 19121 Total number of accounts in
KB
Mentiri *84167 Total number of accounts in
Brunei Muara
Beribi *84167 Total number of accounts in
Brunei Muara
Table 12: Number of customers served
*NOTE: No detailed information on the number of customers served in Mentiri and Beribi, thus total
number of accounts in Brunei Muara is used.
Upon calculation of customer minutes of interruptions (CMI) for respective 11 kV substations for year
2013 and 2014 (Appendix 2), SAIDI values were calculated and have been tabulated in Figures 7a and 7b
as shown below.
Draft dated 27th May 2015 21 of 34
Figure 7a: SAIDI chart for 11 kV substations
Figure 7b: SAIDI chart for 11 kV substations - with step restoration analysis
Draft dated 27th May 2015 22 of 34
6.2.2 SAIFI calculation for 11 kV substations
Estimate of SAIFI is carried out for the three substations mentioned earlier. It is observed that the value of
SAIFI for Kuala Belait and Mentiri increases from 2013 to 2014, this is possibly due to deteriorating of
the equipment for example excess lightning, storm and animal contact.
Figure 8: SAIFI chart for 11 kV substations
Draft dated 27th May 2015 23 of 34
6.3 Analysis of three 66 kV substations in Brunei Darussalam. Three representative 66 kV substations have also been analyzed to obtain the SAIDI and SAIFI values,
which are:
Kuala Belait Substation
Mentiri Substation
Beribi Substation
6.3.1 SAIDI calculation for 66 kV substations
To develop the estimates of SAIDI for the three 66 kV substations, a few parameters were looked into in
the power outages data provided by DES (Appendix 2), as mentioned in previous chapter (Chapter 5).
The parameters are:
If restoration of power occur in full or in steps (step restoration)
If Major Event Day is involved (outage which will increase the SAIDI value – typically due to
natural disasters where outages can last for days)
A few step restoration scenarios were identified in Kuala Belait outages in the year 2014 and 2013. From
the data given by DES, there were no recorded outages in 66 kV substations Mentiri for year 2014 and
Beribi for the year 2014 and 2013. Further breakdown on calculation of SAIDI for step restoration is laid
out below (Tables 13- 21). The calculation of SAIDI which involves step restoration cannot be done
accurately as the number of customers restored at a particular restoration time is not known in detail.
Thus, in this calculation, it is assumed that equal number of customers are restored at each restoration
time.
KB Outage on 04/06/2014
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 9561 - - - -
1 50% 4781 4780 1:30 PM 1:55
PM 25 4781 119512
2 50% 4780 0 1:30 PM 2:35
PM 65 4780 310732
TOTAL 100% 9561 - - - - 9561 430245
Table 13: Step restoration calculation for power outage in KB on 04/06/2014
Draft dated 27th May 2015 24 of 34
KB Outage on 21/07/2014
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time
on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 9561 - - - -
1 33% 3187 6374 11:15 AM 12:45
PM 90 3187 286829
2 33% 3187 3187 11:15 AM 1:23
PM 128 3187 407936
3 33% 3187 0 11:15 AM 1:47
PM 152 3187 484424
TOTAL 100% 9561 - - - - 9561 1179189
Table 14: Step restoration calculation for power outage in KB on 21/07/2014
KB Outage on 07/08/2014
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer minutes
of interruption
(CMI)
- 0% 0 9561 - - - -
1 50% 4781 4780 10:19 PM 10:50
PM 31 4781 148195
2 50% 4780 0 10:19 PM 11:23
PM 64 4780 305952
TOTAL 100% 9561 - - - - 9561.00 454147
Table 15: Step restoration calculation for power outage in KB on 07/08//2014
KB Outage on 20/03/13
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 742 - - - -
1 25% 186.00 556.00 6:37 AM 8:57 AM 140 186 26040
2 25% 185.00 371.0 6:37 AM 9:45 AM 188 185 34780
3 25% 185.00 186.00 6:37 AM 10:55 AM 258 185 47730
4 25% 186.00 0 6:37 AM 12:56 PM 379 186 70494
TOTAL 100% 556 - - - - 742 179044
Table 16: Step restoration calculation for power outage in KB on 20/03/2013
Draft dated 27th May 2015 25 of 34
KB Outage on 20/06/13
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 180 - - - -
1 33% 60.00 120.00 10:50
AM 12:45 PM 115 60.00 6900
2 33% 60.00 60.0 10:50
AM 2:10 PM 200 60.00 12000
3 33% 60.00 0 10:50
AM 6:09 PM 439 60.00 26340
TOTAL 100% 180 - - - - 180 45240
Table 17: Step restoration calculation for power outage in KB on 20/06//2013
KB Outage on 02/07/13
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 6235 - - - -
1 50% 3118 3118 1:15 PM 2:05 PM 50 3118 155875
2 50% 3118 0 1:15 PM 2:57 PM 102 3118 317985
TOTAL 100% 6235 - - - - 6235 473860
Table 18: Step restoration calculation for power outage in KB on 02/07/13
KB Outage 18/07/13
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 13158 - - - -
1 50% 6579 6579 8:37 PM 9:00 PM 23 6579 151317
2 50% 6579 0 8:37 PM 9:38 PM 61 6579 401319
TOTAL 100% 13158 - - - - 13158 552636
Table 19: Step restoration calculation for power outage in KB on 18/07//2013
Draft dated 27th May 2015 26 of 34
KB outage 02/08/2013
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 6279 - - - -
1 33% 2093.00 4186.00 10:48 PM 12:21 AM 93.00 2093 194649
2 33% 2093.00 2093.0 10:48 PM 12:52 AM 124.00 2093 259532
3 33% 2093.00 0 10:48 PM 1:26 AM 158.00 2093 330694
TOTAL 100% 6279 - - - - 6279 784875
Table 20: Step restoration calculation for power outage in KB on 02/08//2013
KB Outage 07/11/2013
Scenario
order
% of
customers
restored
Customers
restored
Customers
remaining
interrupted
Time off Time on
Interruption
duration
(min)
customers
interrupted
(CI)
Customer
minutes of
interruption
(CMI)
- 0% 0 116 - - - -
1 50% 58 58 10:00
AM 11:14 AM 74 58 4292
2 50% 58 0 10:00
AM 11:45 AM 105 58 6090
TOTAL 100% 116 - - - - 116.00 10382
Table 21: Step restoration calculation for power outage in KB on 07/11/2013
Upon calculation of customer minutes of interruptions (CMI) for respective 66 kV substations for year
2013 and 2014 (Appendix 2), SAIDI values were calculated and have been tabulated in Figures 9a and 9b
as shown below.
Draft dated 27th May 2015 27 of 34
Figure 9a: SAIDI chart for 66 kV substations
Figure 9b: SAIDI chart for 66 kV substations with step restoration calculation
Draft dated 27th May 2015 28 of 34
6.3.2 SAIFI
SAIFI calculations have been carried out for the three substations mentioned earlier. It can be observed
that the SAIFI values for Kuala Belait and Mentiri decrease from 2013 to 2014. Since, there were no
recorded outages in Beribi for the two consecutive years, the SAIFI value remains zero.
Figure 10: SAIFI chart for 66 kV substations
Draft dated 27th May 2015 29 of 34
7. POWER OUTAGE
Power system outage means a failure of part of the power supply system for example transformer out of
service, an open breaker when it should be closed, and a line down [6], a power outage consequentially
will lead to a number of consumers being in an absence of electrical energy for a duration of time [3].
Power outage can last a few hours up to several days, and this may greatly impact businesses,
manufacturers (in downtime and lost production) [8], and hospitals.
7.1 Causes of power outages.
There are several reasons that may contribute to power outages, such as weather – related outages (i.e
lightning, rain) and other outages caused by man and animals. While it is possible to identify the causes of
power outages, absolute future power outage prevention is highly unlikely to take place, but it can be
minimized up to a certain degree.
Weather related power outages
Faulty equipment – faulty underground cable
Overcurrent – trip
Flashover transformer
Animal contacts
People induced including – pole and overhead contacts underground digging [9]
7.1.1 Weather related power outages.
A large number of power failures and outages are caused by natural weather such as thunderstorm, high
winds, snow, ice and even dust [7]. In Brunei Darussalam, the occurrence of lightning and thunderstorm
is highly frequent, thus, this can be categorized as one of the main causes of power outages in this
country. Power outages are mainly caused by damage from trees falling on electrical lines and poles,
especially on longer transmission lines which carry bulk power [8], thus circuit breakers or other
protective equipment shut off power flow [13]
Draft dated 27th May 2015 30 of 34
7.1.2 Faulty Equipment
Faulty underground cable has also been identified as one of the reasons for power outages in Brunei
Darussalam.
7.1.3 Overcurrent
Overcurrent occurs when excessive electric current flows through a conductor, which may dangerously
lead to excessive generation of heat and cause failure in equipment. Thus, circuit breakers trip to shut off
power flow.
7.1.4 Flashover transformer
This happens when power lines touch each other or the ground, and consequently lead to short circuit and
an arc or a flashover.
7.1.5 Animal Contacts
Animals such as monkeys and squirrels may climb on certain pieces of equipment (transformers and
fuses), which consequently causes the equipment to shut down [13].
7.1.6 People induced including: pole and overhead contacts and underground
digging
Pole and overhead contacts during maintenance and excavation work by contractors may accidentally hit
underground cables, thus, directly affecting power supply [9].
7.1.7 Short Circuit
Short circuit happens when an electric current travels a different path from the planned one in an
electrical circuit [7]. Due to the excessive electric current, this may lead to circuit damage and
consequentially fire and explosion.
7.1.8 Electrical Trees
Electrical treeing is a scenario which affects high power installations such as high power cables and
transformers [7]. Partial electric discharges may form in the equipment due to impurities or mechanical
defect used in high voltage installations [7]. If the fault goes undetected, this can lead to constant
degradation of the equipment and finally result in a major breakdown – power loss [7]
Draft dated 27th May 2015 31 of 34
7.2 Examples of power outages (historical blackouts).
Power outages are common in this modern world, but its adverse effects have played a major role in
trying to improve the electrical power system. Some power outages have affected thousands of people,
and lasted for a couple of days, in which, this has led to further economic losses.
Brazil and Paraguay (10 November 2009)
This outage occurred due to natural event; where continuous heavy rain and strong winds had caused a
number of transformers to short circuit and consequentially shutting all 20 turbines in the hydroelectric
power plant due to sudden fall of power demand. This incident has put a halt to subways operations, and
most of Brazil’s phone network collapsed. This outage has affected about 87 million people, and lasted
from 25 minutes to 7 hours [10].
India (2 January 2001)[cite]
A technical failure, more specifically, failure of substation in Uttar Pradesh has caused a widespread
of power outages which affected major hospitals, treatment plants, and pumping stations. As a result
from this failure, millions of people were affected as the water supply broke down. The outage has
also caused chaos in train and land operations. This disruption has affected 226 million people, and
lasted for 12 hours and economic losses were estimated to be USD 110million [10].
USA (North – East) + Canada (Central) 14 August 2003.
A large area of Midwest and Northeast United States and Ontario, Canada suffered from power
outages due to human error, lack of maintenance and total equipment break down. The power outage
lasted for four consecutive days and 50 million people were affected. A total economic loss of USD 6
Billion was also recorded. [10]
From the list of examples of outages, it can be observed that reliability of electrical power system plays a
major role in everyday life. A power outage may last from a few hours to a few days, and the economic
loss a country has to endure during this period can reach billions of dollars. Thus, it is important to put
emphasis on reliability of power system, to benchmark and simultaneously improve the electrical power
system supplied to consumers.
Draft dated 27th May 2015 32 of 34
8. CONCLUSION
Reliability indices measurement for SAIDI and SAIFI has been carried out for three 11 kV and 66 kV
substations in Brunei Darussalam which are Kuala Belait, Mentiri and Beribi substation. Different types
of interruptions were looked into, and to provide consistent policy to all four districts, only sustained and
unplanned interruptions are included to review and improve current reliability performance.
In the event of widespread of power outages, restoration of power needs to be done in stages (steps).
Thus, step restoration sample calculation has been outlined to calculate SAIDI more effectively, by
varying the number of customers restored per stage since the number of customers restored at each stage
is not known in detail. A few causes of power outages have also been identified in Brunei Darussalam
such as weather – related causes (lightning and thunderstorms), faulty equipment, and animal contacts.
Furthermore, collection of more data (five years of data) would enable the study of the reliability trend of
SAIDI and SAIFI numbers. Specific power outages could also be identified such as problematic circuits
or failing of specific equipment, thus, further corrective action can be taken to benchmark DES to other
utilities worldwide.
This power failure may affect a large number of people and may greatly impact businesses,
manufacturers, hospitals and cause economic losses; thus, improving power reliability is of utmost
importance.
Draft dated 27th May 2015 33 of 34
9. FUTURE WORK
From the SAIDI and SAIFI calculations developed for Brunei Darussalam, a few measures can be taken
to improve the accuracy of the calculations, such as having a more detailed record of power outages. DES
is currently doing a remarkable job at recording power outages across Brunei Darussalam; further
addition on the number of customers restored at each restoration stage would greatly increase the
accuracy of SAIDI and SAIFI calculation.
One of the causes of prolonged power outages in Brunei Darussalam is due to the delay in mobilization of
personnel to affected areas. Further design improvement of distribution systems using Smart Grid
technologies [13] would identify fault location, and enable personnel to reach the affected area faster,
thus, a decrease in time to normalize the power outage [11] and a reduced SAIDI number.
Furthermore, implementation of advanced intelligent real–time communications-based load shedding
schemes can be employed to minimize the number of customers interrupted by matching actual loads to
required loads to be shed [14]. Typically, pre–determined feeders regardless of actual load (based on peak
loading conditions) are selected to shed the required loads.
Assume priority order for load shedding is Feeder 1, Feeder 2, Feeder 3 and finally, Feeder 4. Assume
that the required load shed in stage 1 under frequency is 8 MW. Assuming peak loading for Feeder 1,
Feeder 2, Feeder 3 and Feeder 4 is 2, 3, 5 and 8 MW, respectively. During the requirement for under
frequency load shedding, the actual loading is 1, 2, 3 and 6 MW respectively. This conventional scheme
will result in a total of 12 MW; 4 MW greater than what is necessary. Thus, the utilization of intelligent
load shedding [14] would only select Feeder 2 and Feeder 4 to total 8 MW and unnecessary load shedding
can be avoided and a better SAIDI and SAIFI number achieved.
Draft dated 27th May 2015 34 of 34
References
[1] Energy Department, Prime Minister’s Office, Energy White Paper, Bandar Seri Begawan: Energy
Department, Prime Minister’s Office, 2013.
[2] IEEE Guide for Electric Power Distribution Reliability Indices, IEEE Std 1366-2012, 2012.
[3] Marko Cepin, “Assessment of Power System Reliability: Methods and Applications”, London:
Springer. [Online].
[4] Richard E. Brown, “Electric Power Distribution Reliability”, 2nd
edition, USA: CRC Press, 2008
[Online]
[5] Council of European Energy Regulators, “CEER Benchmarking Report 5.1 on the Continuity of
Electricity Supply”, CEER, Brussels, Belgium, REF: C13-EQS-57-03, 2014 [Online].
[6] H. Lee Willis, “Power Distribution Planning Reference book”, 2nd
edition, USA: New York: Marcel
Dekker AG, 2004.
[7] “The Many Causes of Power Failures” Internet:
http://www.dieselserviceandsupply.com/Causes_of_Power_Failures.aspx, [Apr. 31, 2015]
[8] Richard J. Campbell “Weather – Related Power Outages and Electric System Resiliency”,
Congressional Research Service, 2012.
[9]“ Distribution Feeder Principles” Internet:
https://www.gedigitalenergy.com/multilin/resource/Feeder/UniFlip_Publication/document.pdf [Date
accessed]
[10] “Power Blackout Risks”. Internet:
https://www.allianz.com/v_1339677769000/media/responsibility/documents/position_paper_power_blac
kout_risks.pdf
[11] “ How the Smart Grid Makes Restoration Faster and Easier for Utilities” Internet:
http://www.silverspringnet.com/outage/pdfs/SilverSpring-Whitepaper-Outage.pdf
[12] “Causes of Power Outages” Internet: https://www.duke-energy.com/north-
carolina/outages/causes.asp
[13] “ Smart Grid Investments Improve Grid Reliability, Resilience, and Storm Responses”
https://www.smartgrid.gov/sites/default/files/doc/files/B2-Master-File-with-edits_120114.pdf
[14] Farrokh Shokooh, et. Al. “An Intelligent Load Shedding (ILS) System Application in a Large
Industrial Facility,” in Proc. Industry Applications Conference, 2005, pp. 417-425, vol. 1.
Draft dated 27th May 2015 A
Appendix
Appendix 1: Power Outages for 2014 and 2013 Kuala Belait Outages for 2014 (for 11 kV substation)
Date Description Action Taken Time off Time on Duration of
Interruptio
n in mins
Affected area No. of
custo
mers
affecte
d
Customer
minutes of
interruption
07-
01-14
Transformer tripped at
substation Telekom
Fault was due to bushing
HT terminal yellow phase
which leaked. Temporary
power supplied through
gengset. Transformer was
replaced by SEC
Mashibah at 8.00 am and
power supply is
normalized.
7.45pm 9.30pm 105
2 210
20-
01-14
Faulty underground cable
from substation Jalan A until
X22
Found out that MIS Setia
Di-Raja TAMCO (panel
10) and MIS Hospital
(Panel 3 – Panglima 1)
tripped.
Sg Tujoh and Mumong
received power at 7:03
PM.
Jln Panglima and Jalan
Maulana received power
at 8:55PM.
JlnPandan received power
at 10:40 PM
6.20pm 10:40pm 260 PekanBelait
Kg Pandan
RPN Kg Pandan
Pandan 3&4
Pandan 6
Kg Mumong Utara
Kg Mumong Selatan
Mumong (postpaid)
JalanSetiaDiraja
8867 1353692
31-
03-14
Incoming panel number 2
from SetiaDiraja tripped on
o/c at MIS BatuTiga
Overcurrent trip triggered,
open bus section to
distribute loading.
7:00pm 7:28pm 28 Pandan 6
Kg Pandan
4473 125244
Draft dated 27 May 2015 B
RPN Kg Pandan
JalanMaulana
JalanMaulana,
SgPandan
11-
05-14
Faulty underground cable
from in between substation
Pandan 5 and Substation
Wisma Yakin
Power supply given from
S/S Kerma Negara to S/S
Wisma Yakin at 5:00PM.
Power supplied from S/S
Batu 2 to S/S Pandan 5 at
5:25 PM
12:15pm 5:25pm 310 Kg Pandan
RPN Kg Pandan
JalanMaulana
JalanMaulana,
SgPandan
4445 1322387
28-
05-14
RMU flashover at substation
H3 Spg 15 Pandan 5
Trip at TAMCO MIS
SetiaDiraja Panel 5 and
found RMU flashover at
S/S H3.
Normalised affected area
at 1:15 PM.
Temporary power given
to Spg 15 at 5:15 PM.
Spg 29 and Spg 80-22
received power supply at
6:30 PM.
Repairs of RMU started at
6:00 PM and ended at
12:50 AM.
11:37 PM 6:00 PM 98
JalanMaulana
JalanMaulana, Sg.
Pandan
Kg Pandan
RPN Kg. Pandan
Pandan 3&4
3144 858311
09-
07-14
1000KVA transformer
flashover at substation H21
Spg 2431-3
Temporary power supply
given through gengset
from 8:00 PM until 2:50
AM. Power normalized
back at 3:00 AM.
5:00 pm 8:00 pm 180 JalanMaulana
JalanMaulana,
SgPandan
Pandan
Kg. Pandan
RPN Kg. Pandan
3092 556560
Draft dated 27 May 2015 C
21-
07-14
Panel 5 Panaga Fuji to circuit
Kuala Balai trip on
overcurrent
Switch on again.
Intermittent fault.
9:30 am 11:15 am 105 Kg Kuala Balai 169 17745
31-
07-14
Panel number 5 to circuit
Kuala Belait trip on
overcurrent at MIS Panaga
Switch on again.
Intermittent fault.
7:00 pm 7:15pm 15 Kg Kuala Balai 169 2535
09-
08-14
Panel number 5 Fuji to
circuit Kuala Balai trip on
overcurrent at MIS Panaga
Switch on again.
Intermittent fault.
5:45pm 7:30 pm 105 Kg Kuala Balai 169 17745
02-
11-14
Fault 800KVA transformer at
substation Buruh housing
Temporary power
supplied through 500
kVA started at 4:20 PM.
2:45pm
4:20pm
95 Kg Mumong Utara
Kg Mumong Selatan
Mumong (postpaid)
3627 344565
09-
12-14
ERM feeder (Substation
SekolahPersediaan Arab to
Substation Mumong A) trip
due to BSP contractor
(seismic project) hit
underground cable (blue
phase) between substation
Jati 6 and Jati 7.
Affected areas normalized
at 3:20 pm.
2:07 pm
3:20 pm 73 Kg Mumong Utara 2582 188486
Kuala Belait Outages for 2013 (11 kV substation)
Date Description Action Taken Time off Time on Duration of
Interruptio
n in mins
Affected area No. of
custo
mers
affecte
d
Customer
minutes of
interruption
31-12-13 Received complaint from
144 informing low voltage
Low voltage found at S/S
w7 and S/S Batu 4 due to
66 kV transformer at MIS
Panaga low tapping and
changed tapping from 6 to
9.
10:00 PM 12:00 AM 120 JalanMaulana
JalanMaulana
(postpaid)
901 108120
Draft dated 27 May 2015 D
02-01-13 Flashover of transformer at
substation Jati 1 Spg 120-
48-35-9
Changed to a new
transformer. Temporary
power supplied using two
gengset.
5:00 PM 12:00 AM 420 STKRJA area, SPG
120-48-35-9, SPG
120-48-35-10 and
JalanDipa Negara
189 79380
04-03-13 Faulty underground cable
from human work?
Isolated faulty cable
between MIS Batu 3 until
S.S Eng Hong. Supplied
power through ring.
9:30AM 12:05 PM 155 JalanMaulana
JalanMaulana
(postpaid)
JalanPandan 1
JalanPandan 2
JalanPandan 3
Pandan 7
Pandan 8
1305 202275
21-03-13 Faulty underground cable
from MIS BT.3 to
substation Eng Hong
Power supplied via
alternative circuit.
8:50 AM 9:31 AM 41 JalanSingaMenteri
Pandan 8
667 27347
27-03-13 Faulty underground cable
between MIS Panaga to
Substation Kuala Balai
Power supplied from 4
gengset at S/S Kuala Balai.
9:40 AM 6:30 PM 530 JalanSingaMenteri
Kuala Balai
545 288850
26-04-13 Power cut off Power cut off due to
animal contact on jumper
HT cable and aerial cable,
which caused breaker at
Panel Bandaran to get
tripped. Switched off
supply to S/S SgDuhon and
switched breaker back on
at MIS SetiaDiraja.
4:25 PM 4:45 PM 20 Jalan Sungai Duhun 7 140
22-6-13 Power cut off Found RMU 2R2T (ABB)
flashover at s/s Kuala Balai
A. Temporary power
supplied using 4 gengset.
7:00 AM 10:45 AM 225 Jalan Kuala Balai 50 11250
13-07-13 Power cut off Found out transformer
1000Kva tripped at S/S
8:18 AM 9:45 AM 87 309 26883
Draft dated 27 May 2015 E
Kuala Balai E HjTalip.
Switched back on, and
normalized affected area.
16-07-13 No power Found faults at station
transformer. Temporary
power supplied using
mobile generator.
7:50 PM 10:45 PM 175 1 175
03-08-13 Faulty underground cable
due to human work??
Found out underground
cable from Jati 7 to S/S
penapisan najis 1 (JKR)
faulty and a trip at MIS
Panaga. Isolated faulty
underground cable and
found out more faults at
cable from S/S Mumong to
package unit (RMU) at
S/S. Power supply
normalized at 4:00 PM
except Spg 284 Mumong,
power supplied through
generator at S/S Saluran
najis at 10: 00 PM
11:30 AM 10:00 PM 630 JalanSingaMenteri
Pandan 8
Mumong B
Kg Mumongutara
Mumong (postpaid)
3309 2084670
26-08-13 Power cut off Checked and found out
transformer No. 3 tripped
due to overcurrent at MIS
Setia DiRaja Siemen.
Transformer switched back
on and normalized affected
areas.
1:45 PM 3:30 PM 105 Pekan KB
Kg Pandan
RPN Kg Pandan
JlnMaulana, SgPandan
(postpaid)
Pandan 3&4
Pandan 6
5210 547050
27-08-13 Power cut off 1000 kVA transformer
tripped at S/S Jalan Patai.
Transformer switched back
on.
4:00 PM 4:30 PM 30 JlnPetai
LubokNipah
56 1680
14-10-13 Power cut off Electricity tripped at
TAMCO Panel 5 at MIS
10:50 AM 12:26 PM 96 JalanSetiaPahlawan 217 20832
Draft dated 27 May 2015 F
Setia Di Raja. Found out
there was a flashover at
termination in RMU in S/S
Pejabat Elecktrik.
Normalised affected areas.
JalanSgSatu
Pandan 5
Pandan 6
Beribi Outages for 11kV substation 2014
Date Description Action Taken Time off Time on Duration of
Interruptio
n in mins
Affected area No. of
custome
rs
Affected
Customer
minutes of
interruption
30-03-14 Substation Jalan Jasmin
Beribi
Feeder T tripped.
The RMU oil type (Long
&Crowfort).
Change to RMU (Brush
Hacker Siddley)
2:00 PM 3:30 PM 90 Jalan Jasmin Kg
Beribi
17 1530
21-04-14 Overcurrent due to load
transfer
Transferred load and
energized one by one by
considering the load.
9:00 AM 11:32 AM 152 Baiduri Bank
Kg Kiarong
Kg Beribi
Kg Kiulap
5496 835392
22-05-14 MIS Telanai P#13
tripped and indicated
earthfault and
overcurrent.
HV underground yellow
phase faulty.
12:30 AM 1:50 AM 80 Spg 493, Spg 2,
Flat E, SgSunda
Housing
New Housing Kg
Beribi
75 10500
21-09-14 MIS Beribi Industry
Phase 1 P#4 tripped to
ERM Beribi Industry 3
and indicated earthfault.
3:00 AM 4:30 PM 90 Light Beribi
Industrial area
5 450
Draft dated 27 May 2015 G
22-09-14
HV cable faulty
transformer to ERM.
HV cable blue phase
faulty from ERM Beribi
Industry 3 to substation
Industry 5 faulty
11:30 AM 12:00 AM
30
Light Beribi
Industrial Area
5 150
15-10-14 Overcurrent 6:47 PM 8:47 PM 120 Kg Jansak
Kg beribi
Royal Escot Housing
Smart Beribi
JalanBunga Jasmin
Beribi
JalanDamuan
Mentiri Housing area
3298 395760
Beribi Outages for 11kV substation on 2013
Date Description Action Taken Time off Time on Duration
of
Interrupt
ion in
mins
Affected area No. of
custome
rs
affected
Customer
minutes of
interruption
03-02-13 TX 300 kVA tripped.
Check and found oil level
empty. Energise and
tripped.
Isolate and earth for
testing. Found LV side
faulty (TX)
04:40 PM 5:50 PM 70 Spg 199
JalanPermaisuaraBerib
i PAP Noraian
12 840
24-04-13 Panel 12 tripped to ERM
Beribi 1. Megger and
found HV cable from S/S
Beibi Industry 2 to S/S
Beribi Industry 3 faulty.
(Yellow and Blue phases
Isolated and earthed the
fault.
09:38 AM 10:47 AM 69 Bangunan Bina Block
A, B & C Beribi
Industry
100 6900
Draft dated 27 May 2015 H
faulty)
08-05-13 MIS Beribi Industry Fasa
1 P#3 tripped and
indicated earthful and
overcurrent. Isolate and
megger. Found HV cable
from S/S Spg 466 to S/S
Government Cooperative
Store (BINA) Beribi
faulty.
Isolated and earthed the
fault.
06:45PM 8:00 PM 75 Bangunan BINA,
PerindustrianFasa 1,
Spg 466 and Spg 456
Kg Beribi
34 2550
29-06-13 TX 1000 kVA tripped. Check and energized. 12:00 AM 12:30 AM 30 Industry Beribi 100 3000
01-07-13
TX 1000 Kva tripped,
check and found the TX
faulty.
Isolate and earth. 09:40AM 10:09 AM 29
KilangPlastikPerindust
rianBeribi,
BombaBeribi Industry
100 2900
03-07-13 P#19 tripped to MIS S1
Kiarong and indicated
overcurrent.
Energise P#2 & P#19 to
balance load.
11:05 AM 11:50 AM 45 Kg Tungku
Kg Kiarong
Gadong
Kg Beribi
6305 283725
06-07-13 Trip from overcurrent
and third phase detach
from MIS Beribi Industry
PH#12 & S/S ERM
Industry Ringan 1 P#7 –
HV cable faulty from S/S
#2 to S/S #3 & S/S #3 to
S/S #4.
09:00 AM 09:25 AM 25 Beribi Industry and
Block C
13 325
Draft dated 27 May 2015 I
18-08-13 TX 800 Kva tripped.
Intermittent tripped.
08:40 AM 09:00 AM 20 PerindustrianBeribi 1 15 300
19-08-13 Feeder MIS Telanai P#11
& P#5 tripped and
indicated earthfault.
Found HV cable from
MIS Beribi Industry 1
P#11 to MIS Telanai
P#11. (2 phases faulty)
09:30 PM 11:37 PM 127 Kg Jangsak
Kg Telanai
Kg Beribi
Beribi Industry
3944 500888
02-09-13 Complaint TX tripped at
Sph 456 Kg Beribi.
Found HV cable from
S/S 456 Kg Beribi to S/S
Spg 424 Kg Beribi.
03:30 AM 04:45 AM 75 Spg 456, Spg 424, Kg
Beribi
61 4575
28-09-13 TX 1000 kVA tripped. Checked and energized 10:35 AM 11:30 AM 55 Gardenia Factory
Beribi Industry
1 55
08-10-13 TX 800 kVA tripped Checked and energized. 08:15 AM 09:00 AM 45 Gardenia Factory 1 45
08-10-13 TX 800 kVA tripped. Checked and energized. 09:45 AM 10:00 AM 15 Gardenia Factory 1 15
12-10-13 TX 800 kVA tripped. Checked and energized
release the protection
wiring (relay).
08:20 AM 09:00 AM 40 Gardenia Factory 1 40
21-11-13 66/11 Kv Beribi P#5
tripped to MIS Kiulap 1
and MIS Spg 32 tripped
to MIS Kiulap P#8 MIS
Kiulap 1 to MIS Spg 32
Isolate and earth. 04:15 AM 07:00 AM 165 Hua Ho Kiulap,
KomplexSetiaKenang
an,
151 24915
Draft dated 27 May 2015 J
Kiarong P#9 flashover. Hotel Kiulap and
Kiulap Mall
03-12-13 Feeder T tripped and
checked. Energised and
found TX 800 kVA
faulty.
Isolate and earth. 01:20 PM 02:00 PM 40 Flat F14 Kg Beribi 6 240
Draft dated 27 May 2015 K
Mentiri Outages for 11kV substation for 2014
Date Description Action Taken Time off Time on Duration
of
Interrupt
ion in
mins
Affected area No. of
custome
rs
affected
Customer
minutes of
interruption
23-03-14 Feeder TX1 incomer
tripped P#4. Intermittent
fault (animal trespassing
the aerial cable)
Open all the outgoing
feeder and close the
incomer – Intermittent
tripped (animal contact)
01:20PM 03:09PM 111 PerpindahanMentiri
Mentiri
SgBesar
Kapok
Kg Salar
Buloh
BatuMarang
Bukit Sebangin
PengkalanSibabau
3429 380619
27-05-14 Feeder incomer TX1
tripped and found relay
faulty. Intermittent
tripped (relay faulty)
06:55AM 07:58AM 63 Kg Salar
Kg Mentiri
PerpindahanMentiri
SgBuluh
Bukit Sebangin
Kg Kapok
SgBesar
3122 196686
04-07-14 Incomer feeder tripped
because SF6 gas is low.
Close bus section. 04:32 PM 06:18PM 166 Kapok
Tanah Jambu
SgBuloh
4448 738368
Draft dated 27 May 2015 L
Mentiri
23-07-14 Incomer 66/11Kv Mentiri
TX1 tripped at 11Kv
PANEL 8. Isolate P#8. –
Intermittent tripped.
Close bus section 08:43AM 09:16AM 33 Kg Mentiri
Kg SgBesar
Sungai Buloh
Tanah Jambu
Mentiri
4084 134772
19-10-14
Feeder T tripped check
and found the feeder
pillar vandalized.
09:20AM 0935AM 15
Street Lighting and
Pump Mentiri
2 30
Mentiri Outages for 11 kV substation for 2013
Date Description Action Taken Time off Time on Duration
of
Interrupt
ion in
mins
Affected area No. of
custome
rs
affected
Customer
minutes of
interruption
11-03-13 MIS Mentiri P#10
tripped to S/S Spg 444
SgBesar and indicated
overcurrent. Test and
found S/S Opp Klinik Sg
Besar RMU NEI
flashover at T feeder.
Isolate and earth.
Requested for a generator.
01:20AM 02:25 AM 65 Kg Mentiri
Kg Sungai Besar
886 57590
05-04-13 Feeder TX2 incomer
tripped at 11kV feed to
MIS Mentiri and
indicated overcurrent. –
11:45PM 02:00 PM 132 Perumahan Kg Mentiri
Kg Sungai Bunga
KlinikSgBesar
1585 209220
Draft dated 27 May 2015 M
Aerial cable termination Kg SgBesar
Kg Mentiri
28-05-13 Incomer panel at GIS
Mentiri TX2 tripped and
S/S Spg 444 tripped
overcurrent. Found S/S
Spg 444 termination
flashover. – Termination
HV cable flashover
06:20PM 07:50PM 90 PerpindahanMentiri
Kg PengkalanSibabau
Kg Mentiri
SgBungadan Golf
1476 132840
22-06-13 TX 500 kVA tripped. –
Intermittent tripped
Checked and energise.
RMU MG cover remove
need to install back.
03:40PM 04:27 PM 47 PerkhidmatanAwamK
elabMentiri
4 188
Kuala Belait outages for 66kV substation for 2014
Date Description Action Taken Time off Time on Duration
of
Interrupti
on in mins
Affected area No. of
custome
rs
affected
Customer
minutes of
interruption
30-05-14 Transient fault
– could be due
to lightning
strikes ,
momentary
tree and animal
contact
Seria #2 feeder tripped at LPS
66kV S/S at 8:08am with ARC
operated but failed to operate.
21Distance Zone B, Phase & Earth
fault, 86B lock out protection relay
activated, total load loss of 18MW.
Attempt to reenergize the feeder
was succesfully at 8:23am, thus
normalizing all affected areas.
8:08 AM 8: 23 AM 15 Half of Seria and
Kuala Belait areas
9561 143415
04-06-14 Transient fault
– could be due
to lightning
strikes ,
momentary
tree and animal
Seria #1 feeder tripped at LPS
66kV S/S at 1:30pm with ARC
operated but failed to operate,
21Distance Zone 1, C, Phase &
Earth fault locator, 86B lock out
protection relay activated, total load
1:30 PM 02:35 PM 65 Half of Seria and
Kuala Belait areas
9561 430245
Draft dated 27 May 2015 N
contact loss of 22MW. Attempt to
reenergize the feeder was
succesfully at 1:55pm, but tripped
at Anduki 66kV S/S. Seria #1
feeder was successfully reenergized
at 2:35pm at Anduki 66kV S/S,
thus normalizing all affected areas
21-07-14 Bus coupler A
tripped due to
under frequency
relay activated
whilst Seria # 2
feeder tripped
by the
activation of
load shedding
protection and
further
investigation on
GTG #12
tripping
11:15 AM 01:23 AM 128 Half of Seria and
Panaga and Belait
areas
9561 1179189
07-08-14 Bad weather/
Lightning
Transmission Unit received
information from KB Engineer that
Seria #1 feeder tripped at LPS at
10:19pm. Attempt to reenergize
the feeder succesful at 10:50pm but
only registered 15MW of load and
KB areas still without power
suspected Slimpole #1 feeder at
Panaga 66kV S/S tripped. Delay at
LPS was due to phase
discrepancies relay unable to be
reset remotely, so SIC needed to go
to yard to manually reset at LCC.
KB Engineer and Personnels
normalized KB from Panaga
(Slimpole #1 feeder) at 11:23pm,
thereby normalizing all affected
areas
10:19 PM 10:50 PM 31 Half of Seria and
Panaga and Belait
areas.
9561 454147
Draft dated 27 May 2015 O
28-08-14 Load shedding
activated –
feeder at Seria #
2 tripped
Seria #2 feeder tripped at LPS at
12:44pm with Main and Back up
Lock Out Relay operated and a load
loss of 28MW. Attempt to
reenergize the feeder succesfully at
12:55pm, thereby normalizing all
affected areas.
10:19 PM 10:30 PM 11 Half of Seria and
Panaga and Belait
areas
9561 105171
26-11-14 Animal contact Seria #2 feeder tripped at LPS at
1:37pm with 86A & 86B Lock Out
Relay operated and a load loss of
27MW. Transmission Unit just
informed of feeder tripped at
1:45pm Attempt to reenergize the
feeder successfully at 1:54pm,
thereby normalizing all affected
areas.
1:37 PM 1:52 PM 16 Half of Seria and
Panaga and Belait
areas
9561 152976
Kuala Belait outages for 66kV substation for 2013
Date Description Action Taken Time off Time on Duration
of
Interrupti
on in mins
Affected area No. of
custome
rs
affected
Customer
minutes of
interruption
06-02-13 Suspected
transformer
winding fault
The supplies were normalized vide
Tx#3 Pauweltrafo on Line #1 by
transferring load at Panaga 11kV
MIS Tamco at 4:15pm, Thus
normalizing the affected areas.
3:20 PM 4:15 PM 55 Panaga
PerumahanMumong
JalanMaulana
PerpindahanPandan 8
Batu 4
Perumahan Kg
Panaga
3081 169455
Draft dated 27 May 2015 P
20-03-13 Animal contact The feeder was successfully
reenergized at 8:57am, thus
normalizing Sg Liang areas.
Bukit Puan areas normalized at
9:45am .Rampayoh areas
normalized at 10:55am. All
affected areas were normalized by
this time.
Bukit Puan to Rampayoh 66kV
circuit was successfully
reenergized at 12:56pm.
6:12 AM 08:57 AM 165 Part of Sg Liang area
Whole of Bukit Puan
Rampayoh
Labi areas
742 179044
25-04-13 Lightning
strikes
Seria #1 feeder tripped at Anduki
66kV S/S after ARC succesfully at
LPS 10:21pm. Attempt to
reenergize Seria #1 feeder was
succesfully at 11:07pm by KB
District Engineer. All affected
areas were normalized by this time
10:21 PM
11:07 PM 46 Half of Seria
Panaga
Kuala Belait areas
6279 288834
29-04-13 Lightning
strikes
Seria feeder #2 was tripped with
21Distance Zone 1 A&C, lock out
86A, 86C, LoLr relay protection
operated as per inform by LPS SIC
at 6:35pm.
Attempet to reenergize Seria
feeder#2 was successfully at
6.47pm with initial load of 11MW.
All supplies were normalized by
this time
6:35 PM 06:47 PM 12 Half of Seria
Panaga
Kuala Belait areas
6279 75348
20-06-13 Unknown Manually opening circuit breaker
and both isolator switch at Bukit
Puan. Affected areas normalized
vide by closing the N/O point 11
kV RMU at Luagan Lalak intake
station.
10:50 AM 01:15 AM 195 Whole of Bukit Puan
Rampayoh
Labi areas
180 45240
Draft dated 27 May 2015 Q
30-06-13 Wrong wiring
connection
Tx#1 tripped with OLTC oil level
trip flag protection relay operated at
7:50am. Attempt to reenergize
back Tx#1 was failed as relay flag
cannot be reset. All affected areas
were normalized by energized Tx#2
and load transfer at Anduki 11kV
MIS. 9:45am. Tx#1 was inspected
and test on the next day and found
out that OLTC oil level ALARM
flag at Tx#1 cubicle at switchyard
wiring wrongly connected to OLTC
oil level Trip flag at relay room
6:55 AM 08:50 AM 115 Areas of Anduki
Third ABDB
batillion
PerpindahanLumut
SgTali
1307 150305
02-07-13 Lightning
thunderstorm in
KB areas
Seria #1 feeder tripped with phase
and Earth fault locator, 21 Distance
Zone A protection relay operated at
1:15pm. Attempt to reenergize
Seria #1 feeder was successfully at
2:05pm with initial load of 5MW.
A total loss of 19MW after tripped
still unknown. Upon checking KB
#1slimpole feeder at Panaga was
tripped. Feeder was successfully
reenergized at 2:57pm. All affected
areas were normalized by this time.
1:15 PM 02:57 PM 102 Whole of Anduki
Half of Seria
KB areas
6235 473860
09-07-13 Fallen tree onto
overhead line
conductors
Telisai #1 incoming feeder tripped
at 2:30pm as per inform by KB
District Engineer at 2:45pm. The
Telisai #1 feeder was succesfully
reenergized back after feeder
tripped. Attempt to reenergize back
Labi feeder, Sg Liang to Bukit
Puan segment was successfully by
manually Open Circuit Breaker at
Sg liang and Circuit Breaker &
both Isolator Switch at BukitPuan .
The affected areas were normalized
vide 11kV RMU at Terunan intake
station at 4:57pm. The suspected
fault, Bukit Puan to Rampayoh
segment was reenergized back at
3:11pm on Thursday 11th July
2:30 PM 4:57 PM 147 Areas at Sg Liang
Whole of Bukit Puan
Kg Sg Mau
Rampoyah
Labi areas
847 124509
Draft dated 27 May 2015 R
2013 after surveying done and
checking the resistance on the Red,
Yellow and Blue phases of the
Overhead line segment
18-07-13
Intermittent
fault –
momentary tree
contact,
lightning strikes
and animal
contacts
Pasir Puteh #1 feeder tripped at
8:37pm. Attempt to reenergize
Pasir Puteh #1 feeder was
successful at 9:00pm. At the same
time Panapar#1 feeder at Pasir
Puteh 66 kV S/S also tripped.
Attempt to normalized from
SCADA was failed with operation
block indicated. An attempt to
reenergize the feeder at 9:38pm
was successful by DES Tutong. All
affected areas were normalized by
this time.
8:37 PM 09:38 PM 61 Areas at
mukimTanjong Maya
Perpindahan Bukit
Beruang
Kg Bukit Beruang
MukimTelisan
Sg Liang
Whole of JalanLabi
areas
Part of Serambangun
MukimLamunin
MukimRambai
Penapar
MukimUkong areas
13158 552636
24-07-13 Overhead line
overload
Seria #1 feeder at Anduki 66kV S/S
was tripped at 3:12pm. Attempt to
reenergize the feeder at Anduki
66kV S/S was successfully at
4:00pm.
3:12 PM 04:00 PM 48 Areas at Panaga and
Kuala Belait
288 13824
02-08-13 Animal contact Anduki #2 feeder at Seria 66 kV
S/S tripped at 10:48pm. Attempt to
reenergized failed at 11:15pm,
indicate a present of permanent
fault between Seria to Panaga and
Panaga to KB segment. The survey
was done with the help of
contractor but no possible fault was
found. The affected areas were
normalized at 12:21pm for Seria
10:48 PM 01:26 PM 158 Half of Seria
Panaga
One third of Kuala
Belait areas
6279 784874
Draft dated 27 May 2015 S
areas, Panaga areas at 12:52am and
KB areas at 1:26am, thus
normalizing all the affected areas.
02-08-13 Transient fault Telisai#1 feeder at Pasir Puteh 66
kV S/S tripped approximately at
4:18pm with 21D Zone 1, A G, Red
Phase to Ground. Attempt to
reenergized the feeder was
successful at 5:16pm. All affected
areas were normalized by this time.
4:18 PM 05:16 PM 58 Whole of Bukit Puan
Rampayoh areas
Sg Liang
Lumut areas
8689 503962
03-08-13 Unknown Tx#1 at Bukit Beruang 66 kV S/S
tripped approximately at 9:22am
with 87T Differential protection
relay activated indicated a fault on
the transformer. The supplies were
normalized vide 11kV Bukit
Beruang MIS by closing the Bus
Section at 10:18am. The
transformer was measured and
tested but no possible fault was
found. Tx#1 was successful
reenergized back at 12:55pm
4:10 PM 05:06 PM 56 Kg Bukit Beruang
Perpindahan Bukit
Beruang
Bukit Beruang
Primary School
2040 114240
07-08-13 Contractor
accidentally
excavated 66kV
underground
cable
Panapar Slimpole #1 feeder at
Panapar 66 kV S/S tripped at
approximately 10:40am with 21D
Zone 1, A, B, C. All supplies were
normalized vide 11kV MIS
Lamunin by closing the bus section
at 11:48am. An attempt to
reenergized the feeder was
successful at 3:30pm and put the
feeder on soak, by isolating the
Panapar to Lamunin underground
cable feeder.
5:38 PM 06:46 PM 68 Areas at Panapar
Kg Ukong
Bukit Barun Water
Treatment Plant
Layong Water raw
Kg Layong
Kg PangkalanTangsi
1075 73100
20-08-13 Weather related
outage
Lumut #1 feeder tripped at 2:55pm
with 21Distance Zone 1
Protection relay activated and a
total load loss of 9MW.
8:20 AM 08:29 AM 9 Areas at Mile 8
Kilanas Pump Station
Kg Jangsak
2796 25164
Draft dated 27 May 2015 T
Attempt to reenergize Lumut #1
feeder was successfully at 3:04pm,
therefore normalizing all affected
areas.
Kg Lamunin
Kg Managah
Kg Bukit Sulang
Kg PangkalanTangsi
Bukit Barun Water
Treatment Plant
Kg Layong
07-11-13 Treee fallen
onto the
overhead line
conductor and
snapped.
A complained received at 10:00am,
no electrical supply at MukimLabi
areas. Upon checking Labi feeder at
Sg Liang tripped at Earth fault
protection relays operated with total
load loss of 2MW. Attempt to
reenergize back Sg Liang to Bukit
Puan feeder segement was
successfully at 11:14am,
normalizing Bukit Puan areas. All
supplies were normalized by
11:45am by closing N/O point at
Terunan RMU.
10:00 AM 11:45 AM 105 Whole Bukit Puan
Rampayoh areas
116 10382
29-11-13 Transient fault
– animal
contact,
lightning strikes
and momentary
tree contact
Seria #2 feeder at LPS 66 kV S/S
tripped at 10:15am with 21 trip
Zone 1, Distance
protection relays, operated with a
total load
loss of 19MW. An attempt to
reenergize the feeder at 10:25am
was successful, thus normalizing all
affected areas. Survey of the
overhead transmission line was
done on the same day but no fault
was found.
10:15 AM 10:25 AM 10 Half of Seria, Panaga
and Kuala Belait
areas
6279 62790
Draft dated 27 May 2015 U
Mentiri Outages for 66 kV for 2013.
Date Description Action Taken Time off Time on Duration of
Interruption
in mins
Affected area No. of
custome
rs
affected
Customer
minutes of
interruption
16-6-13 Transient faut –
momentary tree
contact on the
overhead
conductors /
lightning
Attempt to reenergize the Muara
#B feeder was successfully done at
6:18pm after DTCB Mentiri#B at
Muara was switched OFF.
Mentiri#B was switched ON,
thereby normalizing all affected
areas.
2:20 PM 4:20 PM 120 Parts of Kg Serasa
Kg Sabun
Kg Kapok
2915 349800
08-08-13 Bad weather,
lightning during
the feeder
tripped
Muara #B feeder at Mentiri 66 kV
S/S tripped at 1:06pm with 21D
Zone 1, L2 & EF protection relay
activated. An attempt to reenergize
back the feeder was successful at
2:00pm, thus normalizing all the
affected areas.
1:06 PM 2:00 PM 54 Areas at Muara Port
Kg Sabun
Kg Serasa
PerpindahanMeragan
g
PekanMuara
3616 195264
19-08-13 Intermittent
fault
Muara #B feeder at Mentiri 66 kV
S/S tripped at 2:40pm with 21D
Zone 1, L2 & EF protection relay
activated. An attempt to reenergize
back the feeder was successful at
4:30pm, thus normalizing all the
affected areas.
2:40 PM 04:30 PM 110 Areas at Muara Port
Kg Sabun
Kg Serasa
PerpindahanMeragan
g
PekanMuara
3616 397760
Draft dated 27 May 2015 V
20-08-13 Fallen tree
branches onto
the overhead
line
Labi feeder at Sg Liang 66 kV S/S
tripped at 8:20am with 51
overcurrent protection relay
operated. An attempt to reenergize
back the feeder was successful at
9:58am, thus normalizing all the
affected areas.
8:20 AM 9:58 AM 98 Whole of Bukit Puan
Rampayoh Labi areas
180 17640
Draft dated 27th May 2015 W
Appendix 2: List of required data for accurate calculation of SAIDI and SAIFI
Required Data 2015 2016
General Data
Total number of customer served
in supply area
Date of outage
Type of interruption
Beginning and end of
interruption
All kind of interruption (classify
as momentary, sustained or
planned)
Unusual interruptions (lasts for
days)
Consequences
Number of customers
affected/interrupted
Affected area
How is the power restored?
Step restoration or full
restoration
If step restoration is involved,
state:
The stages
Duration of restoration
time for each stage
Number of customers
interrupted and restored
at each stage.
Cause of interruption
Draft dated 27th May 2015 X
Planned
Unplanned
Natural disaster (weather- related
)
Human behavior
Operational cause
External cause
Other causes