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State Estimation following Cyber Attacks on the Power Grid Saleh Soltan, Mihalis Yannakakis, Gil Zussman Electrical Engineering and Computer Science Columbia University, New York, NY
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State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Apr 18, 2018

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Page 1: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

StateEstimationfollowingCyberAttacksonthePowerGrid

SalehSoltan,Mihalis Yannakakis,GilZussmanElectricalEngineeringandComputerScience

ColumbiaUniversity,NewYork,NY

Page 2: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Security and Resilience

Physical Attacks/Failures Cyber Attacks/Failures

Control

Data Power

Power Grid Communication networks Physical Infrastructure

Supervisory Control and DataAcquisition (SCADA) system

Page 3: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Source: Report of the Commission to Assess the threat to the United States from Electromagnetic Pulse (EMP) Attack, 2008

FERC, DOE, and DHS, Detailed Technical Report on EMP and Severe Solar Flare Threats to the U.S. Power Grid, 2010

Large Scale Physical Attacks/Failures

◆ EMP (Electromagnetic Pulse) attack

◆ Solar Flares

Photos from National Geographic

◆ Other natural disasters

Page 4: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

IdentifyingCommunicationsNetwork’sMost VulnerableParts

◆ Cutswith probabilisticproperties • Distancefrom theattack’s

epicenter• Thetopographyofthe

surroundingarea

• Thecomponent’sspecifications ◆ Anumberofsimultaneous

attacks ◆ Takeintoaccountprotection and

restoration

◆ Use computationalgeometrictools forcomplexityreduction

P. K. Agarwal, A. Efrat, S. K. Ganjugunte, D. Hay, S. Sankararaman, and G. Zussman, “The resilience of WDM networks to probabilistic geographical failures,” IEEE/ACM Transactions on Networking, vol. 21, no. 5, pp. 1525–1538, Oct. 2013.

Page 5: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Power Networks – Vulnerability and Cascade Analysis

A. Bernstein, D. Bienstock, D. Hay, M. Uzunoglu, and G. Zussman, “Power grid vulnerability to geographically correlated failures - Analysis and control implications,” in Proc. IEEE INFOCOM’14, 2014.

Page 6: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Power Networks – Vulnerability and Cascade Analysis

Page 7: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Power Networks – Vulnerability and Cascade Analysis

Page 8: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Power Networks – Vulnerability and Cascade Analysis

Page 9: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Power Networks – Vulnerability and Cascade Analysis

Page 10: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

N-Resilient, Factor of Safety K = 1.2 ® Yield = 0.33 For (N-1)-Resilient ® Yield = 0.35 For K = 2 ® Yield = 0.7

(Yield - the fraction of the demand which is satisfied at the end of the cascade)

PowerNetworks– VulnerabilityandCascadeAnalysis

Page 11: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

PowerGridAttackinSanJose(Apr.2014)◆ “AsniperattackinApril2014thatknockedoutanelectricalsubstationnear

SanJose,Calif.,hasraisedfearsthatthecountry'spowergridisvulnerabletoterrorism. ”–TheWallStreetJournal

Page 12: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

CyberAttackinUkraine(Dec.2015)

◆ Unplugged225,000peoplefromtheUkrainianelectricitygrid• StealcredentialsforaccessingtheSCADAsystem,beforeJune2015• ExploreofSCADAsystemandplanattack, June-Dec.2015• Remotelyoperatecircuitbreakers,dayofattack• Phonejammingattackskeepsoperatorsunaware,dayofattack

Page 13: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Interdependencies(Nov.2012)

Hurricane Sandy Update

IEEE is experiencing significant power disruptions to our U.S. facilities in New Jersey and New York. As a result, you may experience disruptions in service from IEEE.

Page 14: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Interdependencies◆ FCCWorkshopworkshoponnetworkresiliency(2013)

https://edas.info/web/fcc-nr2013/program.html◆ ReportoftheCommissiontoAssessthethreattothe

UnitedStatesfromElectromagneticPulse(EMP)Attack,2008

◆ Modeling:• Simplecascades• Powercontrolwith

limitedcommunications/imperfectinformation

• Powerloss(eventual)impactoncommunications

Comm.LogicalLayer

Comm.PhysicalLayer

PowerGrid

S. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,” Nature 464, 1025-1028 (15 April 2010) -> Google Scholar

Page 15: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

BacktoAutonomousEnergyGrids

◆ Communicationiscrucialforcoordinateddistributedcontrol◆ Controlwithoutcommunicationorwithimperfectinformation– suboptimal?◆ Arethecellsresilientwithoutcommunication?

B. Kroposki, E. Dall’Anese, A. Bernstein, Y. Zhang, B.-M. Hodge, “Autonomous Energy Grids ,” Proc. HICSS, 2018

Page 16: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Cascades and Interdependencies

Synthetic Power Grids

Cyber Attacks

Islanding, Limited Information

OngoingResearch

Prediction Detection

ControlEvaluation

Page 17: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

DARPARADICSProgram

◆ RADICS- RapidAttackDetection,IsolationandCharacterizationSystems

◆ Respondtocyber-attacksonU.S.criticalinfrastructure

◆ TA1- Usegridmeasurementstoidentifyattacks

◆ Scenariosin“Exercise#1”(May2016):• Disconnectline+falsedatainjection• Disconnectlineandload+falsedata

injection• Largescalecascade

80-Bus Transmission system overlaid on the Washington DC area

Page 18: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

StateEstimationafteraCyber-PhysicalAttack- Outline

◆ StateestimationundertheDCmodel◆ Stateestimationinthepresenceofmeasurementnoiseand

uncertainty◆ StateestimationundertheACmodel◆ Attackidentificationwhentheaffectedareaisunknown*focusontransmission

[1] Saleh Soltan, Mihalis Yannakakis, Gil Zussman, “Joint Cyber and Physical Attacks on Power Grids: Graph Theoretical Approaches for Information Recovery,” IEEE Transactions on Control of Network Systems (to appear), 2017.

[2] Saleh Soltan and Gil Zussman, “Power Grid State Estimation after a Cyber-Physical Attack under the AC Power Flow Model,” Proc. IEEE PES-GM’17, 2017.

[3] Saleh Soltan, Mihalis Yannakakis, Gil Zussman, “EXPOSE the Line Failures following a Cyber-Physical Attack on the Power Grid ,” in preparation.

[4] Saleh Soltan, Mihalis Yannakakis, Gil Zussman, “REACT to Cyber Attacks on Power Grids,” submitted.

Page 19: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Simplisticview ofa PowerGrids

Control Center

Commands

Data

Cyber Attack TargetPhysical Attack Target

Supervisory Control and Data Acquisition (SCADA) system

Power GridPhysical Infrastructure

Zone 1

Zone K-1

Zone K

PMUs PDC

PDC

Communication Network

PMUs

PMU

PMU

PMU

PMU

PMU PDC

Comm.Net.

PMU: Phasor Measurement UnitPDC: Phasor Data Concentrators

Page 20: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

SimpleAttackModel

◆ AnadversaryattacksanareabyØ Disconnectingsomelineswithintheattackedarea(physicalattack)Ø Disallowingtheinformationfromthemeasurementdeviceswithintheareato

reachthecontrolcenter(cyberattack)◆ Assumeweknow!◆ Acyberonlyorphysicalonlyattackmayresultinasimilarsituation

"

!

AttackedArea

Page 21: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

PowerFlowEquations- DCApproximation

◆ Representthegridbyaconnectedgraph" = (%, ')

◆ TheDCpowerflowisasolution()⃗, ,⃗) of:-,⃗ = .⃗

/01,⃗ = )⃗

0 ∈ {−1,0,1}8×::theincidencematrixofthegrid:

;<= = >

0, ifA=isnotincidenttonodeI,

1, ifA=iscomingoutofnodeI,

−1, ifA=isgoingintoofnodeI,

/ ∈ ℝ:×::thediagonalmatrixofadmittancevalues,

and- = 0/0N :theadmittancematrixofthegrid

O

P

Load (.Q < 0)Generator (.Q > 0)

,Q, .Q

,Q: Phase AngleUQV:Reactance

Page 22: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Objective

Objective:Usetheinformationavailableoutsideoftheattackedzone(,⃗′XY)andtheinformationbeforeattack(-, ,⃗)

Ø Recoverthephaseangles(,⃗′X)Ø Detectthedisconnectedlines(Z)or(-′)

! : an induced subgraph of " that represents the attacked zone!Y: "\!Z : Set of failed lines¡′ : The value of ¡ after an attack

"

!

AttackedArea

Z

,⃗′ =,⃗′X

,⃗′XY

Page 23: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

RelatedWork

◆ Linefailuredetectionisacombinatorial problem◆ Previousworkonlinefailuresdetectionusingphaseanglemeasurements:

◆ Singleordoublelinefailures(TateandOverbye,2009)• Linefailureidentificationinaninternalsystemusingtheinformationfroman

externalsystem(ZhuandGiannakis,2012)• PMUlocationselectionforlineoutagedetection(Zhao,Goldsmith,Poor,2012)• Recoveryintransientstate(Garciaetal.,2016)• Topologyattacks(KimandTong,2013)• …

◆ WeusethealgebraicpropertiesoftheDCpowerflowequationsandthegridstructuretoefficiently(LP)detectlinefailures

◆ Weshow(empirically)thattheapproachoperateswellwithmeasurementnoiseandundertheACpowerflows

◆ WeextendtoACpowerflowsandcasesinwhichtheattackareaisunknown

Page 24: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

InformationRecovery

◆ Assumethatsupply/demandvaluesdonotchangeorweknowchanges

\ -,⃗ = ]

-^,⃗^ = ]⇒ - ,⃗ − ,⃗^ = -^ − - ,⃗^

⇒-X|a-XY|a

,⃗ − ,⃗^ =-′X|a − -X|a

-XY|a^ − -XY|a

,⃗^

-XY|a ,⃗ − ,⃗′ = 0 -X|a ,⃗ − ,⃗′ = 0XU⃗

-XY|a ,⃗ − ,⃗′ = 0

-X|a ,⃗ − ,⃗′ = 0XU⃗

Recover the phase angles Detect Line Failures

Simultaneous phase angles recovery and failed lines detection

" !

Z

!Y: "\!¡′ : The value of ¡after an attack

Does not depend on the number of line failures

Page 25: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

RecoveryofPhaseAngles

◆ ,⃗′X canberecoveredafteranyattackon!,if-XY|X haslinearlyindependentcolumns

◆ ,⃗′X canberecoveredalmostsurelyifthereisamatchingbetweenthenodesinsideandoutsideof! thatcovers%X

H

-XY|a ,⃗ − ,⃗′ = 0 ⇒ -XY|X,⃗X^ =-XY|a,⃗ − -XY|XY,⃗XY

^

- =-X|a-XY|a

=-X|X -X|XY

-XY|X -XY|XY, ,⃗′ = ,⃗′X

,⃗′XY

Matching: A set of pairwise nonadjacent lines

Page 26: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

DetectingFailedlines

◆ bO.. U⃗ : SetofnonzeroelementsofvectorU⃗

◆ Failedlinescanbedetected,if! isacyclic◆ Whatifthesetoflinefailuresissparse?

min ∥ U⃗ ∥d b. f. 0XU⃗ = -X|a(,⃗ − ,⃗′) (∗)

Lemma. There exists a vector U⃗ ∈ ℝ hi such that 0XU⃗ = -X|a ,⃗ − ,⃗^

and bO.. U⃗ gives indices of the failed lines.

Lemma. The solution U⃗ is unique, if and only if ! is acyclic.

Page 27: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

DetectingFailedlines

Theorem. In a planar graph !, the solution to (∗)min ∥ U⃗ ∥d b. f. 0XU⃗ = -X|a(,⃗ − ,⃗′)

is unique and bO.. U⃗ gives indices of the failed lines, if the following conditions hold:(i) for any cycle, less than half of its lines are failed,(ii)Z∗ can be covered by edge-disjoint cycles in !∗

!

Lemma. If ! is a cycle and less than half of the lines are failed, then the solution U⃗ to the optimization (∗)is unique and bO.. U⃗ gives indices of the failed lines.

min ∥ U⃗ ∥d b. f. 0XU⃗ = -X|a(,⃗ − ,⃗′) (∗)

Example

Page 28: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

SimultaneousPhaseAnglesRecoveryandFailedlinesDetection

◆ FindvectorsU⃗ ∈ ℝ|hi| and,⃗′X ∈ ℝ|ki| suchthat0XU⃗ = -X|a(,⃗ − ,⃗′)

-XY|a ,⃗ − ,⃗′ = 0

◆ Uniquesolutionif,andonlyif,1. ! isacyclic2. Thereisamatchingbetweenthenodesin! and!Y

◆ bO..(U⃗) givestheindicesofthefailedlines

◆ Assumingthesetoflinefailuresissparse:

min ∥ U⃗ ∥d b. f.

0XU⃗ = -X|a(,⃗ − ,⃗′)

-XY|a ,⃗ − ,⃗′ = 0

(∗∗)

Page 29: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

SimultaneousPhaseAnglesRecoveryandFailedLinesDetection

◆ Example.

Theorem. Under some conditions on Z and ! the solution U⃗, ,⃗′X to(∗∗) is unique and can recover the missing information.

min ∥ U⃗ ∥d b. f.

0XU⃗ = -X|a(,⃗ − ,⃗′)

-XY|a ,⃗ − ,⃗′ = 0

(∗∗)

!-inner-connected

!

Page 30: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

ConditionsandConstraints

External Conditions Internal Conditions Attack Constraints

Matching Acyclic None

Matching Planar Less than half of the edges in each cycle are failed

Partial Matching AcyclicLess than half of the edges

connected to an internal node are failed

Partial Matching Planar Two above conditions

"

!

AttackedArea

Z

Page 31: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

PartitioningoftheColoradostategridinto6attack-resilientzones

◆ NP-Hard◆ Developedgoodapproximations

Page 32: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Outline

◆ Stateestimationunderacyberandphysicalattack◆ Stateestimationinthepresenceofmeasurementnoiseand

uncertainty◆ StateestimationundertheACpowerflows◆ Attackidentificationwhentheaffectedareaisunknown

Page 33: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

MeasurementNoiseandUncertainty

◆ Assume- ,⃗ − n = .⃗

n isaGaussianmeasurementnoise

◆ lmn = 20log∥p∥q

∥r∥q

◆ Relaxtheconstraintsasin(∗∗∗)

◆ Secondorderconeprogramming

min ∥ U⃗ ∥d b. f.

||0XU⃗ − -X|a ,⃗ − ,⃗^ ||s < td

||-XY|a ,⃗ − ,⃗′ ||s < ts

∗∗∗

"!

Page 34: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

NumericalResults

Page 35: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

NumericalResults

Could not detect failure in Ad

Page 36: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

NumericalResults

False Negative: Not detecting a failed lineFalse Positive: Detecting an operating line as failed

Page 37: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

StateEstimationundertheACPowerFlows

◆ PhaseangleofthenodesarecomputedundertheACpowerflows

◆ Usedifferenttd andts valuesandstatisticallydetectthelinefailures

◆ IEEE118-bussystem- anattackedareawith21nodesand22lines

min ∥ U⃗ ∥d b. f.

||0XU⃗ − -X|a ,⃗ − ,⃗^ ||s < td

||-XY|a ,⃗ − ,⃗′ ||s < ts

∗∗∗"

!

Saleh Soltan and Gil Zussman, “Power Grid State Estimation after a Cyber-Physical Attack under the AC Power Flow Model,” Proc. IEEE PES-GM’17, July 2017.

Page 38: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

StateEstimationundertheACPowerFlows

◆ Thephaseanglescanbeestimatedwithlessthan1%errorfor1-,2-,and3-linefailures

◆ Linefailurescanalsobedetectedwithlessthan20%error(falsepositivesornegatives)

The CDF of the number of false negatives and positives in detecting triple line failures (100 cases).

Page 39: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

DealingwithACDirectly

◆ Recoveringthevoltages• Similarconditions• Non-linearbutconvex

◆ DC-basedmethod:

◆ AC-basedmethod:

◆ EvaluationwhenZonedoesnotsatisfyconditions

Saleh Soltan, Mihalis Yannakakis, Gil Zussman, “REACT to Cyber Attacks on Power Grids,” in preparation.

118-bus 300-bus

Detected Lines

Fa

ile

d L

ine

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

Detected Lines

Fa

ile

d L

ine

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

Page 40: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Outline

◆ Stateestimationunderacyberandphysicalattack◆ Stateestimationinthepresenceofmeasurementnoiseand

uncertainty◆ StateestimationundertheACpowerflows◆ Attackidentificationwhentheaffectedareaisunknown

Page 41: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

◆ Detectthelinefailuresaswellastheattackedarea! afteracyber-physicalattack

BacktoDC- LocationUnknown

Saleh Soltan, Mihalis Yannakakis, Gil Zussman, “REACT to Cyber Attacks on Power Grids,” submitted.

Page 42: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

◆ Twotypesofcyberattacks• Datadistortion• DataReplay

◆ ,⃗⋆ istheobservedphaseanglesaftertheattackwhichisdifferentfromtheactual,⃗′

◆ NP-Hard◆ Approximatesolutions

LocationUnknown- CyberAttacks

Page 43: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

◆ Approximatelydetecttheattackedareain3steps◆ Identifylinefailureswithsomeconfidence

Example

Page 44: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

◆ Simulationsontwoattackedareaswithin300-bussystem• Attackedareaswith15and31nodes

Simulations

Page 45: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Performance- SmallArea

1001,2,3-linefailuresamples

Page 46: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

◆ Replayattacksaremuchhardertocopewith

◆ IEEE300-bus◆ 3linefailures

Distortionvs.ReplayAttacks

Page 47: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Performance- LargeArea

1001,2,3-linefailuresamples

Page 48: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

Summary

◆ Developedschemesfordetectinglinefailuresfollowinganattackusingpartialinformation

◆ Identifiedtradeoffsbetweenthestructuralcomplexityoftheattackareaandtheaccuracyofdatarecovery

◆ EvaluatedundermeasurementnoiseandACmodel◆ DevelopedanAC-basedalgorithm◆ Consideredthecaseinwhichattackedareaisunknownandthereare

falsedatainjections◆ (near)futurework:dealwitha(streaming)simulatedattackona

~1500busgrid…

Page 49: State Estimation following Cyber Attacks on the …. V. Buldyrev, R. Parshani, G. Paul, H. E. Stanley, S. Havlin, “Catastrophic cascade of failures in interdependent networks,”

PostdoctoralPositions– PowerGridResilience◆ ThegroupsofD.Bienstock andG.Zussman (ColumbiaUniversity)◆ DARPA,DOE,DTRA,andARPA-Eprojects◆ Backgroundandexperienceinsomeofthefollowing:optimization,power,

machinelearning,control,algorithmdesign,andcomputationalimplementation

[email protected] ,[email protected]◆ wimnet.ee.columbia.edu