Smart Grid with Large-Scale Integration of Renewable Energy

1

Chen-Ching Liu and Chih-Che Sun

Energy Systems Innovation Center

Washington State University

Pullman, WA, USA

26th Modern Engineering & Technology Seminar, Taiwan, 2016

Challenges for Taiwan Power Grid

2

High penetration of renewable energy

Installation and operation costs

Intermittent resources

Grid controllability and observability

Protection

Smart grid for operation and control of a complex system

Infrastructure

Applications

Nuclear power plants will be phased out by 2025

Renewable Energy

3

Solar power

High installation cost

Construction requires land

Land-based wind farms

Wind and wind power

forecast

Occupies land

Off-shore wind farms

High costs

Source: inhabitat.com

Smart Grid Development in U.S.

4

Transmission Distribution

Synchrophasors

Substation Automation

Renewable Energy Remote Controlled

Switches

Distributed Energy Resources

Advanced Metering

Infrastructure

Source: General Electric and CG global

Investment of Smart Grid in U.S.

5

► Smart grid demonstration

projects (SGDPs).

* Investments include federal and

industry cost-share.

* Updated on March 13, 2015.

◄ Smart grid investment grants

(SGIGs) asset investment.

* Investments include federal and

industry cost-share.

Source: smartgrid.gov

AMI Assets Customer

Systems

Assets

DER Assets Distribution

Assets

Transmission

Assets

$0

$40

$80

$120

$160

$200

$ M

illio

ns

Reported to date

$0

$1200

$2400

$3600

$4800

$6000

$ M

illio

ns

Distribution Assets Transmission Assets AMI and Customer

System Assets

Reported to date Estimated at completion

Future Development of Taiwan Power Grid

6

Renewable Energy

AMI

Cyber Security

Demand Response

Reliability and Stability

Source: ASI Energy, Powercor and ISO-New

England

7

Off-Shore Wind Farm-HVDC-AC Grid

AC

DC

DC

AC

Offshore wind

farms

AC mainland grid

Offshore wind

power

Wind Farm

side VSCGrid Side

VSC(GSVSC)

DC Cable Point of

Common

Coupling

(PCC)

Generation capacity of off-shore wind farms is large

Impact on system security of the integrated power grid

Smart Grid Application: Demand Response

8

Time of Use (TOU) Critical Peak Pricing (CPP)

• Customers pay higher

prices at designated times

(peak time).

• Price and peak time

schedule are fixed and

predefined until the end of

a tariff cycle.

• Customers pay higher

prices in designated times

(peak time).

• Price and peak time

schedule are designated by

power companies. Peak

time duration and price are

based on energy

consumption.

9

Demand Response (CPP)

California Statewide Pricing Pilot (SPP), 2003/2004

Two groups of participants:

• Track A: Customers with average summer energy use

exceeding 600 kWh per month.

• Track C: Customers had smart thermostats and central

air conditioning.

Tested programs:

• TOU

• CPP-F: Customers had a fixed critical peak period and

day-ahead notification.

• CPP-V: Customers had a variable peak period on

critical days and day-of notification.

10

Smart Grid Application: CPP Results from SPP

Tests Day Type Avg. Price (₵/kWh)

Impact P OP D

Track A

CPP-F

Critical weekday 59 9 23 -13.1% average summer

Normal weekday 22 9 12 -4.7% average summer

Track A

CPP-V

Critical weekday 65 10 23 -15.8% average summer

Normal weekday 24 10 14 -6.7% average summer

Track C

CPP-V

Critical weekday 65 10 23 -27.2% average summer

Normal weekday 24 10 14 -4.5% average summer

Track A

TOU All weekdays 22 10 13

-5.9% inner summer

-4.2% outer summer

Critical weekday: Highest prices are in effect.

Normal weekday: Lower prices are in effect.

Inner summer: July to September.

Outer summer: May, June and October.

Source: Charles River Associates. Impact Evaluation of the California Statewide Pricing Pilot Final Report, 2015.

P: Peak period price.

OP: Off-peak period price.

D: Daily price.

Transactive Energy: Auctions

I can reduce 0.5 MWh

usage for $90/MWh

I can increase 0.5 MWh

discharging for $120/MWh I will buy from you 0.5 MWh

reduction.

PV node on WSU campus has to

generate 1 MWh less electricity than is

scheduled in the next 5 minutes

I can reduce 0.5

MWh usage for

$100/MWh

I can reduce 0.5

MWh usage for

$110/MWh

I will buy from

you 0.5 MWh

reduction.

Advanced Metering Infrastructure (AMI)

12

Neighborhood Area Network Data Concentrating Unit Neighborhood Area Network

ANSI C12.12/ WiMAX/ Zigbee

Wide Area Network

Distribution Operating Center

Router/

Firewall

ServerMDMS

User Interface

SCADA network

IEC 60870-5

DNP 3.0

DMS

DMS: Distribution

Management System

MDMS: Meter Data

Management System

AMI Applications

13

Demand Response

Smart Home Technology

Outage Management System

Real Time Monitoring and Control

Source: greenbiz.com, Electric Online and

App Solutions’

AMI Application: Outage Management System

14

Comparison of System Average Interruption Duration Index (SAIDI)

Utility / Country Year SAIDI

Taiwan Power Company

/ Taiwan

2014 17.5

2013 18.1

Korea Electric Power

Corporation

/ Korea

2014 10.9

2013 11.5

Kansai Electric Power

/ Japan

2014 4

2013 5

Outage Management Incorporating Smart Meters

One-line diagram of a distribution system:

Evidence: • Overcurrent flags from FI1, R2, R1;

• Outage reports from smart meters downstream of Fuse3.

OMS: • Determine the actuated protective device

• Determine the faulted line section

BrkAuto. R1

F1

F3

F4

Auto. R2

F2

L2L1

L3

L4

SM1

SM2

SM3

SM4

SM5

SM6

SM7

SM8

SM9

SM10

SM11 SM12

SM13 SM14

Feeder

F: fuse

SM: smart meter

L: lateral

FI1

Multiple-Hypothesis Incorporating Smart Meters

Generate

Hypotheses

Evidence

Credibility of

Hypotheses Optimization

Model

Most Credible Outage Scenario(s)

17

Cyber Attack in Ukraine’s Power System

Location of Power Outage

• Attack on Ukraine’s power grid

December 23, 2015.

Malware installation.

Falsify SCADA data injection.

Flood attack on telephone system.

Trip circuit breakers in multiple

substations.

• Results

Over 225,000 customers

experienced power outage.

Source: Google map

Cyber Security of Power System: Substations

18

Anomaly Detection at Substations

19

20 Sequential attacks – Sub # 6 → 12 → 15 → 28 → 36 → 33 → 34

Cyber Attack on Substations

21 Sequential attacks with ADS

Substation with Anomaly Detection System

• Low power consumption

• Low computational

efficiency

• High sampling rate

• On board battery

• Bidirectional

communication via

wireless or PLC

Voltage

Sensor

Current

Sensor

MemoryStorage

Module

Communication

Module

Micro

Controller

Unit

(MCU)

Single Phase Power Line

Smart Meter

23

Cyber Vulnerabilities of Smart Meters

False data injection

Energy theft

Fraud meter data/status report

Fraud control command injection

Jamming

Losing connection with smart meters

Eavesdrop

Attackers are able to locate an empty house by

analyzing power consumption data.

24

Cyber Security R&D on AMI

Availability

Confidentiality Integrity

Specification-based

Intrusion Detection System

Malicious meter

inspection

Secure wireless

communication

Physical layer-

assisted message

authentication Privacy preserving

metering scheme Nonintrusive load-

shed verification

Distributed IDS

Catastrophic Impact by Natural Disasters

25 Source: 大紀元新聞及宜蘭新聞網

• Typhoon MEGI (Sept. 25 to 28,

2016): Number of customers

experiencing power outage:

over 3.81 million.

• Typhoon MERANTI (Sept. 12

to 15, 2016): Number of

customers experiencing power

outage: over 1.08 million.

Power Outage on Critical Loads

26

• Hsinchu Science Park substation fire accident on

Aug 29, 2012.

Source: 中天新聞

Resilience in Distribution Systems

• Resilience: “..ability to prepare for and adapt to changing conditions

and withstand and recover rapidly from disruptions..”*

• For distribution systems, resilience means the ability to withstand

major disturbances. Fast recovery is essential for a resilient system

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* Office of the Press Secretary of the White House, Presidential Policy Directive 21 – Critical Infrastructure Security and Resilience

[Online]. Available: http://www.whitehouse.gov/the-press-office/2013/02/12/presidential-policy-directive-critical-infrastructure-

security-and-resil

* Source: Nicholas C. Abi-Samra, “One Year

Later: Superstorm Sandy Underscores Need for a

Resilient Grid”, IEEE Spectrum,

http://spectrum.ieee.org/energy/the-smarter-

grid/one-year-later-superstorm-sandy-

underscores-need-for-a-resilient-grid

Microgrids Enhance Restoration Capability

•Generation resources and control capabilities of

microgrids enhance fast recovery of distribution systems

•When a blackout occurs,

microgrids can be controlled

to provide an efficient restoration

strategy to restore critical

loads in the distribution

system and hence improve

the resilience.

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Restoration schemes

considering DERs and

Microgrids

Microgrid

Field Test on WSU Microgrid-Avista System

14

13

11

10

9

SPU121

SPU122

SPU123

SPU124

SPU125

49

48

52

51

50

34/162 37/163

29

35

41/156

30

32/32

39/165

21 2322 24 27

43 15 16

171840/158

38/166

31

36/167 42/161

20/20 19/19

46 45 33 44 47 28 25 26

WSU Microgrid

Hospital

City Hall,

Courthouse &

Police Station

G3

G1

G2

Natural

Gas

Natural

Gas

Diesel

71

91 55

Restoration Scheme for Critical Loads

SPU124SPU122

G3 G2 G11375 kVA

0.8 PF

4.16 kV

/

13.8 kV

4.16 kV

/

13.8 kV

1375 kVA

0.8 PF

2187.5 kVA

0.8 PF

T-B T-A

Diesel Natural Gas Natural Gas

Steam Plant

780 kVA

Feeder 13

550 kVA

IT

705 kVA

SPU121 SPU123 SPU123

City Hall

146.16 kVA

Hospital

382.74 kVA• WSU critical loads are restored

in steps 1-3

• City Hall is restored in step 5

• Hospital is restored in step 7

Simulation Results

•Unbalanced three-phase power flow calculations

•Dynamic simulations

Peak load

Load factor

Governor/Exciter parameters

32

WSU Smart City Testbed

Interfacing with DMS in Testbed

33

TCP/IP

e-terradistributionTM

GE Grid Solutions

Interface Module

DMS

Interface

CSV

Files

System Topologyand DPF Results

Research Applications

(e.g., Spanning Tree)

DMS

Smart City Testbed ... ...

... ...

Data Acquisition and Restoration Actions

e-terra

browser

Restoration Actions

34

IDs of devices in DMS:

• TUR117_395-2425532_68

• TUR117_395-2425534_69

• TUR117_395-2425536_70

Service Restored

35

TUR: Turner

Substation

Recommendations

36

• To set a clear target for the renewable energy portfolio in

Taiwan over the next decade: The target level should stay within the

level of penetration that allows the power grid to maintain high reliability

and stability.

• To deploy Advanced Metering Infrastructure to cover a large

number electricity consumers: AMI enables smart grid applications

including demand response, outage management, and distributed energy

resources.

• To develop and deploy demand response programs for

industrial, commercial, and residential customers in the

Taiwan power system: The goal of demand response is to reduce the

peak load. Time-of-Use (TOU) has been applied to industrial and commercial

customers while Critical Peak Pricing (CPP) has been implemented for

residential customers.

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Recommendations (Cont’)

• To develop cyber security mechanisms for AMI as well

as substation automation facilities: In a smart grid, the system

data/information is transmitted through electronic devices by digital

communications. Cyber security and privacy of customers is essential.

• To develop microgrids for industrial areas and critical

services in order to enhance the resilience of electricity

infrastructure: Catastrophic natural disasters (e.g., typhoons and

earthquakes) have significantly impacted transmission and distribution

facilities in Taiwan.