Large Disturbance and System Security Defense Schemes Herman Darnel Ibrahim

Large Disturbance and
System Security Defense Schemes
Dr. Herman Darnel Ibrahim
Chairman of Indonesian National Committee of CIGRE
Lecturer of Power System Operation and Control Post Graduate Program University Indonesia
MKI and IDNC CIGRE Joint Workshop
Jakarta, 18 September 2019
Large Disturbance and Blackout
▪ Large Disturbance:
Large Disturbance do occur on the system . These include severe
lightning strikes; loss of transmission carrying bulk power, due to
overloading; loss of a generating station; or loss of major load.
[Vijay Vittal, Iowa State University: pserc.wisc.edu]
▪ Large Disturbance:
Large Disturbance in power systems are us ually triggered by some
initial fault and then spread over the system due to combined effect
of many reasons such as malfunction of equipment, lack of
appropriate information and human faults. [Stojsavljevic, Energy
Institute, Croatia: bib.irb.hr]
▪ Blackout:
A blackout is the total loss of power to an area , and is the most
severe form of power outage that can occur. Blackouts which result
from power station tripping are particularly difficult to recover
quickly. [en.m.wikipedia.org].
Possible Causes of Large Disturbance
▪ Large Disturbance usually happen following system’s
component fault. Component faults may cause :
• Generation trip and deficit of generation
• System in-stability
• Line or transformer overloading
▪ Large Disturbance happen when defense scheme does not
work properly. Possible Causes of Large Disturbance:
• Abnormal trip of generation unit [Frequency> 47.5 Hertz]
• In-adequate response of generation [dF/dt >>]
• In-sufficient and in-appropriate Load Shedding
• In-adequate Protection Systems
• Protection system malfunction
Highly Interconnected Power Grid and
Large Disturbances
▪ Interconnection provide greater flexibility and reliability, and
increase system strength [MW/ Hertz].
▪ Simple system has higher risk of power outage [black out]. As
it is small the effect is not severe, and recovery is quick.
▪ Highly interconnected system has lower risk of power outage.
As it is big, it may experience Large Disturbances, the effect is
severe, and recovery may take much longer.
▪ Smaller system in outside Java has higher risk of blackout than
it is in Java Bali system.
▪ In the first month of my duty as Manager of South Sumatera
Control Centre [February 1988], blackout almost happen every
day but recovery was very quick.
Large Disturbance Defense Scheme:
Security "N - 1"
System Remain Stable without: Load
Curtailment, Transmission Overloading
and Exceeding Power Transfer Stability
Limit.
“N – 1” :
System
Experience
Any one of
Component
Outage
System Has
Adequate
Generation
Spinning
Reserve
Non of the
Lines and
Transformers
Experience
Overloading
System
Stability: Limit
of Power
Transfer
Is Not
Exceeded
Large Disturbance Defense Scheme:
Security “N – 2”
System Remain Stable with Load
Curtailment. Load Shedding Scheme should
alleviate Transmission Overloading and
Over Power Transfer of Stability Limit
“N – 2” :
System
Experience 2
Simultaneous
Component
Outage
System Stable
with Load
Curtailment
and No Other
Plant Trip
After Load
Curtailment
Non of the
Lines
Experience
Overloading
After Load
Shedding:
Limit of Power
Transfer
Is Not
Exceeded
Large Disturbance Defense Scheme:
Prevent Plant Trip and Adequate Hot Reserve
System Should Have Adequate and Appropriate Spinning
Reserve when experience “N - 1”:
▪ Following a Disturbance all plant should stay in operation
[maintain No Power Station Trip]. Grid Code: Frequency Set
47.5 Hertz.
▪ Adequate amount of Spinning Reserve: greater than Larges
Unit capacity.
▪ Generation with spinning reserve should be set governor free
or with AGC scheme
▪ Generation with spinning reserve has fast response; adequate
ramping rate [dP/dt] to withstand high dF/dt.
▪ Appropriate distribution or location of spinning reserve, so it
can be evacuated without causing line overloading or system
instability
Large Disturbance Defense Scheme:
Appropriate Load Shedding Scheme
System Should Have Adequate and Appropriate Load
Shedding Scheme:
▪ Load Shedding Scheme should be set to secure “N – 2”
condition.
▪ For Large system, Load Shedding scheme [to secure the large
disturbance] is not simple : it is about amount, location,
frequency setting and speed.
▪ Load Shedding scheme should be reviewed and be reset
following each time system changes.
▪ Modern system apply Smart Load Shedding Scheme executed
and updated on line.
▪ Securing Large Fault [high generation deficit] requires Fast
Load Shedding using “dF/dt” Relay for Larger Load.
Large Disturbance Defense Scheme:
Modern Energy Smart Load Shedding
Change in operation
condition, feeder flow,
generation local capacity,
transformers and feeder
loads
List of
Initiator of
Load
Shedding
Monitoring
and Prediction
of System
Behaviour
Load
Shedding
Optimizer
Knowledge
Base
Utilizes carefully
selected inputs and
outputs, based on off
line studies and models.
Based on prior
defined system
disturbance;
Include topologic
information of
connections and
electrical properties
of the components
of the system
System
Disturbances
Grid
Models
*Source: www.dicsintertrade.com
Programmable
controllers quickly
perform load
shedding based on
the detection of
initiator
Distributed
Control
Programmabl
e Controller
Tables of calculated
optimal load shedding ,
corresponding to
system changes;
Features:
1. Considering system dynamic response.
2. Load to be shed is dynamic and optimal
to suit the system condition change
3. Faster than UFR Load Shedding
Large Disturbance Defense Scheme:
Pre-Set Islanding Scheme
For Large System, Islanding Scheme is set to protect system
from Total Blackout:
▪ Islanding Scheme is usually pre-set by Operation Planning
expert.
▪ An Islanding Scheme is a subsystem contains balanced amount
of demand [load] and generation capacity [similar to Smartgrid
microgrid concept]
▪ A special protection scheme is set to isolate and form the preset island when condition requiring [during disturbance].
▪ Islanding Scheme should be reviewed and updated to
accommodate changes and to ensure it will work properly.
Large Disturbance Defense Scheme:
Maintain Power Transfer Stability Limit
▪ Power Transfer Stability Limit is defined by following formula:
Pmax = [V1* V2/ X] SIN ∂
X
G
2X
V1
4X
G
V2
▪ Maximum transfer with 2 lines operation is 0.5 Pmax , and with
1 line is 0.25 Pmax .
▪ Power transfer must be adjusted if number of lines in
operation change.
▪ A Special Protection must be in place to re-adjust the power
transfer automatically, when number of lines reduced.
Large Disturbance Defense Scheme:
Routine Check of N – 1 Contingency Plan
▪ System condition is dynamic, so that “N – 1” contingency
plan is also dynamic.
▪ “N – 1” Contingency Analyses should be run every time
network topology changes.
Change of:
• Network
Topology
• Generation
• Load
Contingency
“N – 1”
Simulation
[Analyses]
Load Flow:
No Line
Overloading
Stability Limit
Not Exceeded
▪ “N – 1” Contingency plan should always be checked for
significant change of load and generation
Large Disturbance Defense Scheme:
Knowledgeable and Skilled Operator
Operator and Operator Supervisor Have A Good Knowledge
of System Security and High Skill to Take Necessary Action in
Maintaining All System Security Defense Scheme:
▪ Operator should have a sound understanding about all system
security defense scheme.
▪ Operator should have high level of knowledge on how to
maintain system security.
▪ Operators or their Supervisor should run Security Analyses
every time system experience change of topology.
▪ Operator should have high skill in taking action to alleviate
system in-security.
Defense Scheme Check List
No
Defense Scheme
Requirement
Remarks
1.
Contingency N -1
System remain stable without load
shedding.
Must be checked if
system change.
2.
Contingency N-2
System remain stable with load
shedding
Check for Adequate
Load Shedding
3.
Adequate Spinning
Reserve: for N -1
Adequate amount, set governor free,
appropriate location
Fast Response: High
Ramping Rate dP/dt
4.
Appropriate Load
Shedding
Securing N – 2. Right amount, right
distribution, right speed
Dynamic Setting:
Smart Load Shedding
5.
Pre Set Islanding
Scheme
Successful islanding following large
disturbance and system split
Design and Setting of
Scheme
6.
Maintain Stability
Limit
Power transfer must be readjusted if
number of lines reduced
Need special
protection
7.
Running N – 1
Security Analyses
Routine running to check and fix the
N – 1 security from time to time
Software and Skill of
Staff [Operator]
8.
Operator Knowledge High level of knowledge and skill to
+ Skill
maintain power system security
Education and
Training
Status of Operation Condition
Normal
Recovery
▪ All loads is normally
served
▪ Contingency Plan “N – 1” is
satisfied
Changes
Changes
Alert
▪ All loads is still served
[No load curtailment]
▪ "N - 1" Contingency Plan
is not satisfied
Recovery
Recovery
Changes
Emergency
▪ Disturbance Causing
Load Curtailment
▪ "N - 1" Contingency
Plan is not satisfied
Blackout
▪ Severe power outage occur
following disturbance
▪ Total loss of power in an
area
Changes
Operation and Disturbance Experience:
Southern Sumatera System 1988
I was the First Manager of Southern Sumatera Grid Control
Centre:
▪ Computer Based Control Centre for Southern Sumatera System
was first introduced [completed] in February 1988.
▪ At that time a relatively large Coal Steam Power Plant Bukit Asam
2 x 65 MW has just been completed and start its first year
operation. [and still perform various Plant Test and Less Reliable].
▪ Before that Southern Sumatra Power System had 4 power station
with total capacity of 95 MW [ Small SPP, GTPP and DPP], serving
the system peak load of 85 MW [day time 65 MW] through 15
Substations.
▪ System experienced disturbance [mainly due to Power Station
trips] almost every day.
Blackout Experience:
Southern Sumatera System 1988
In the first month of the operation [March 1988] system
experience 26 blackouts.
Subsystem Palembang
City:
Bukit Asam and Outer
Palembang Subsystem:
• Peak Demand ~ 15 MW
[day time ~ 10 MW
• New SPP 2 x 65 MW and
DPP ~10 MW
• 6 Substation
150 kV lines
Up to 65 MW
Operation Condition:
• Largest Unit > Day Time Peak.
• New Units were under testing
• Minimum Defense Scheme [No
UFR, Hot Reserve < Largest Unit]
• Lack of SOP and Communication
Facility
•
•
•
Peak Demand ~ 70 MW
[day time 55 MW]
Generation 85 MW
[SPP, GTPP and DPP]
9 Substation
Handling and Improvement:
• Mostly we knew there will be
blackout
• Quick Recovery ~ 30 minutes
maximum 45 minutes.
• Installed UFR
• Improve SOP and Communication
Example of Large Disturbance:
Java Bali Western-Eastern System Split
West Java
Jakarta and
Banten
System:
~11000 MW
Load,
Importing
Power from
East
Mandirancan
Substation
Short after 11.45 both 500
kV lines TasikmalayaDepok Trip causing system
split Western and Eastern
Tasikmalaya
Substation
500 kV North lines UngaranMandirancan [Cirebon]
At 11 45 , line fault causing
both line tripped.
2300 Megawatt
500 kV South Lines Pedan
Tasikmalaya
1 line maintenance outage
Central
Eastern
Java
System:
Exporting
Power to
the West
Java Bali Large Disturbance:
Western System, After System Split
Other
Island
Scheme
Jakarta
Island
Scheme
Other
Island
Scheme
Other
Island
Scheme
Western System Emergency State:
Load ~ 11.000 MW
Generation ~ 10.000 MW
Loss of Supply [from East] ~2.000 MW
System Response:
Load Shedding ~ 1000 MW
Generation Response ~ 800
Eastern System
Experience Over Supply, Frequency
Increase
Final State :
System Stable
Western System Strength ~ 500
MW/ Hertz, dF/dt ~ High, frequency
may drop more then 3 Hertz
Security Defense :
Generation Response
Load Shedding
V
V...?
Islanding Scheme
?
No Power Station Trip
?
High Speed “dF/dt”
?
BLACKOUT hardly occur in highly interconnected system. It can be prevented
through Defense Schemes. Its risks of happening can be reduced but CAN NOT
BE AVOIDED, as there is no 100% reliability.
World Blackouts
2018 Blackouts
2019 Blackouts
Year
Blackouts
07 Mar Venezuela
10 Jan Sudan
25 Mar Venezuela
21 Jan Sudan
2000-2009 48
09 Jun Texas
27 Jan Sudan
2010
9
16 Jun Argentina
02 Mar US East Coast
2011
13
19 Jul Wisconsin
21 Mar Brazil
2012
6
19 Jul Michigan
12 Apr Puerto Rico
22 Jul New Jersey
03 Jul Azerbaijan
2013
10
04 Aug Indonesia
06 Sep Hokkaido
2014
9
09 Aug England
21 Sep Ottawa
2015
8
01 Sep Bahamas
10 Oct Florida
2016
4
15 Oct Venezuela
2017
11
15 Nov Sulawesi
Past 10 years : 94 Blackouts
04 Dec Saskatchewan 2018 14 Blackouts
2018
14
20 Dec Vancouver
2019 §0 Blackouts
2019
10
*Source: List of Major Power Outages: en.wikipedia.org
Blackout Happen Every Where
India
London UK
Italy
New York
Jakarta
London Underground
Brazil Argentina Paraguay
Japan
Venezuela
2019.09.18 by HDI
MKI CIGRE Workshop
21
Closing Remarks
▪ BLACKOUT hardly occur in highly interconnected system. It can be
prevented through Defense Schemes. The risk of its happening can be
reduced but CAN NOT BE AVOIDED, as there is no 100% reliability.
▪ SECURITY is the MOST IMPORTANT aspect of operation, it is not free,
it has cost. Blackout costs us more than loss of electricity, it cost loss
of income for customers, and costs reputation for the utility.
▪ To minimized the risks of blackout, UTILITY should INVEST in
MODERN HARDWARE and SOFTWARE to put the required Defense
Scheme and SCADATEL infrastructures in place.
▪ UTILITY should also INVEST for continuous improvement of
BRAINWARE and SKILL of its Managers, Engineers and Operators.
Recruit and retain Best and Smart personnel.
▪ It is a common practice in all utilities to do their BEST in preventing
Large Disturbance. However it happen un-intentionally every where.
Stakeholders and society should ACCEPT it as an ACCIDENT.
Biography of Herman Darnel Ibrahim
Chairman of CIGRE [International Council of Large Electric Systems] Indonesian National Committee
Born in 1954. He is a Member of House of Regional Representative [Senator] and was Board
Member of DEN, the National Energy Council of Indonesia 2009-2014 and Former Director of
PLN the State Electricity Corporation [2003-2008]. Beside he serves as Freelance Consultant,
Chair of ICEES [Indonesian Counterpart for Energy and Environmental Solutions], a GLG
Group Council Member, a Lecturer at Faculty of Engineering of University Indonesia, and
Advisor in energy companies.
He also serves as Member of Board of Supervisors of Indonesian Renewable Energy Society [IRES], Vice Chair of
Expert Board of Indonesian Energy Conservation and Energy Efficiency Society [MASKEEI], Member of Expert Board
of Indonesian Power Society [MKI], Advisory Board Member of Indonesia Geothermal Association [INAGA], and
Indonesia Ocean Energy Association [INOCEAN]. He is also active in International Organization, as Chairman of
Indonesian National Committee of CIGRE [International Council of Large Electric Systems] since 2006, and as
Vice President IGA, International Geothermal Association [2013-2016].
Herman got his First Degree in Electrical Engineering from Bandung Institute of Technology [ITB]; M.Sc.
Degree in Electrical Power System Analysis from the University of Manchester, UK; and Doctor Degree in
Technical Science from ITB Bandung with research topic the Energy Policy for Power System Development.
For 30 years until 2008, he worked with PLN, the State Electricity Corporation of Indonesia. He achieved senior
management position at the company as Director Transmission and Distribution [2003-2008], Director of PT.
Indonesia Power, a subsidiary of PLN [1998-2003].
He wrote several papers, public media articles and a book titled Energi Selamatkan Negeri [Energy to Safe the
Country]. In the past decade he contributed as the Speaker and Panelist at several national and international energy
conferences.
Vientiane 18.05.23 by HDI
ASEAN Power Grid
23
Terima Kasih
Thank You
2019.09.18 by HDI
MKI CIGRE Workshop
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