Dugan (EPRI) - Swanson School of Engineering

Roger C. Dugan

Sr. Technical Executive, EPRI

Power Systems Studies

Knoxville, TN

Nov 12, 2013

Distribution System Modeling

Challenges for the Smart Grid

8th Annual Pitt Electric Power Industry Conference

Distribution Systems and Micro-Grid Developments

2 © 2013 Electric Power Research Institute, Inc. All rights reserved.

Distribution Planning Challenges for Grid of the

Future

• The Grid of the Future will rely more on the Information and

Communications Technology (ICT) infrastructure

• Utility distribution planners use Distribution System

Analysis (DSA)

– To design the Power Delivery infrastructure

– They do not include the ICT system

• No integrated tools exist for Distribution Planning with ICT

• Interest in “Co-simulation” of power delivery and ICT is

rapidly growing

– An area ripe for research


Today’s Power System

Base Load

Generation

Load Following

Generation + Bulk Energy

Storage +/–

Customer

Demand = Interruptible

Load DR –


Tomorrow’s Power System

Power System that is Highly Flexible, Resilient and

Connected and Optimizes Energy Resources


The Distribution System Vision

Substation

EV/PHEV

Demand Response

High Penetration PV

Energy Storage

Distributed Controls


Challenge –

Distributed Control Systems


Challenge –

Power Electronics Everywhere

Sa1

Sa2

Sa3

Sa4

Sc1

Sc2

Sc3

Sc4

DC/AC Inverter

+ AC filter

vin

Lf

Sb1

Sb2

Sb3

Sb4

n

VHV_dc

C2

C1

Ldc

a

b

vac1

Ldc Lac

Cdc

Cdc

Lac

Cac

Cac

Transformer +

Rectifier + DC filter

iin iac1

vac2

iac

iac2

vac

+

+

+

+

–

–

––

vab

+

–

van

vab


CVR: 2.5 – 4.5%

energy reduction

ENVO – Edge of Network Voltage Optimization

10 - 100kVAr

Challenge –

Distributed Voltage and Reactive Power Control

From Varentec


Challenge –

Integrating the Customer

Gateways

• Custom Box

• Smart Circuit Breaker Panel

• PC/Router

Apps

DR-Ready Appliances

• Functional Specs

• Communications

Advanced Meters

• Energy Mgmt

• Security


Challenge -

Communications Infrastructure


Exabyte

s p

er

Year

(1 E

xa

byte

= 2

50

Mill

ion

DV

Ds)

1980 1990 2000 2010 2020 2030

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0

Distribution Automation

Substation Automation

Workforce Management

Transmission Sensors

The Era of “Big Data”

Smart In-Home Devices

Building Energy Management

AMI Deployment

Distribution Management

Source: EPRI and CMU

Challenge is Cyber Security – Opportunity is Data Mining


Can We Make it Work?


How Do We Know?


Dist Sys Analysis Needs Envisioned by EPRI

(2007)

• Sequential time simulation

• Meshed network solution capability

• Better modeling of Smart Grid controllers

• Advanced load and generation modeling

• High phase order modeling ( >3 phases)

– Stray voltage (NEV), crowded ROWs, etc.

• Integrated harmonics

– NEV requires 1st and 3rd

• User-defined (scriptable) behavior

• Dynamics for DG evaluations

• Distribution State Estimation (DSE)

Done

DONE


15

Other Key Challenges

• Merging Planning and Real-Time Analysis

• Very Large System Models (1M buses)

• Large Volume of AMI Data

• AMI-based Decision Making

•Detailed LV/Secondary Modeling

• Including multiple feeders, transmission

• DG Integration and Protection

•Generator and Inverter Models for DSA

• Regulatory Time Pressures (Screening Tools)


A Large Gap in Distribution Planning Tools …

• Co-Simulation of Power and ICT Networks

• Distribution System Analysts

– Assume ICT system works

• ICT Network Analysts

– Assume power distribution devices work

• Few tools (if any?) for utility distribution planners to

determine whether or not the combined system will work!


What EPRI Has Done …

• Dugan, Mullen, Godfrey, Rodine “Hybrid Simulation of

Power Distribution and Communications Networks”, CIRED

2011, Paper 1169

– Also, IEEE Comm Soc Paper, Oct 2010

• Hypothetical simulation of using 84 Community Energy

Storage (CES) modules to compensate for solar ramping

with 1-s samples …


Hybrid Simulation of Power Distribution and

Communications Networks – 2010-2011

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0.000 0.500 1.000 1.500 2.000

% Arrival vs time (S)

400mW

80mW

30mW

10mW

0 5 10 15 20 25 300.995

1.000

1.005

1.010

1.015

1.020

1.025

Time (seconds)

Vol

tage

Mag

nitu

de (p

er u

nit)

Base Phase a

Base Phase b

Base Phase c

Phase a

Phase b

Phase c

Without Control

With Control


CIRED 2013 Panel

• “Joint simulation of cyber infrastructure and power

system for smart grid planning and operation studies”

• Roger Dugan, Chair

– Mathias Ekstedt – KTH (Cyber Risk Assessment)

– Craig Breaden – Smarter Grid Solutions (UK) (Active

Distribution Network Test Bed)

– Oliver Gehrke – DTU (Co-simulation of power systems,

controllers and control infrastructure)

– Fabrizio Pilo – U. of Cagliari (Models and tools for ICT

simulation in Active Distribution Networks)


U. Of Cagliari (Italy) Co-Simulation Environment


EPRI’s Research on this Subject

• OpenDSS – Open Source Distribution System Simulator

– Designed for research on distribution system analysis methods for DG and Smart Grid

– Heavily used now for Solar PV impacts simulations

– Available (for free) on Sourceforge.net

– See http://smartgrid.epri.com/SimulationTool.aspx

• ICT Research Portfolio (Matt Wakefield – [email protected]) – http://portfolio.epri.com/Research.aspx?sId=PDU&rId=277

– See also: Smart Grid Resource Center:

• http://smartgrid.epri.com/Index.aspx

http://smartgrid.epri.com/SimulationTool.aspx

http://portfolio.epri.com/Research.aspx?sId=PDU&rId=277

http://smartgrid.epri.com/Index.aspx


Other Resources and Contacts …

• John McDonald – Dist. Engineer @ EDF R&D

• IEEE ISGT Europe

– Committee on ICT Co-Simulation

– Panel at ISGT-Europe in Oct 2013

• Kai Heussen – DTU

• Dr. Heiko Englert – Siemens

• Steffen Schütte – OFFIS (DE)

• Thomas Strasse (Austria)

– And many more …

• Interest in US is not yet as great

– But is accelerating rapidly – Panel at IEEE ISGT 2014


An Example of One Problem…

(Movie

Demo –

Time

permitting)

(Cloud Passing over Distribution Feeder Containing Solar PV Generation)


Together…Shaping the Future of Electricity

“We will see more

changes in the next

20 years than we

have in the last 100

years”

10

Documents

Dugan (EPRI) - Swanson School of Engineering