node-breaker modeling representation validation...node-breaker modeling representation . on december...

Node-Breaker Modeling Representation On December 6, 2016 NERC hosted a webinar on the Node-Breaker model representation. The majority of off-line planning studies currently use bus-branch models to represent power system networks. These models typically represent each substation with a single bus at each nominal voltage level. Without knowledge obtained outside the represented bus-branch model, it is not possible to determine the substation breaker configuration and how it operates during contingencies. The lack of breaker information requires that a large number of contingencies must be manually created to replicate bus contingencies and breaker failure contingencies. This manual effort often presents an opportunity for human errors to occur and takes a lot of time to reconfigure the buses for study work. A solution to this is to use node-breaker models to replace the simplified bus models in the bus-branch configuration. This often requires re-modeling stations into node-breaker topology from the normal Powerflow bus-line configuration. Bus-branch model to node-breaker conversions require creation and maintenance of a mapping of each station into its constituent elements. However, the converse mapping is merely a reduction of zero-impedance elements into the resultant buses. Therefore, use of a node-breaker model is more advantageous to maintain and keep linked to the system topology used in the EMS. These models can provide a fully built out substation representation (e.g., elements such as breakers, switches, branches, or shunts are modeled individually and connected via nodes). Representatives from software vendors (General Electric PSLF, Siemens PSS/E, V&R POM Suite, PowerWorld, DSATools, and eTap) presented on their software modeling capabilities, followed by a Q&A session. For more information or assistance, and to provide comments please contact System Analysis Department (via email) or (404) 446-2560.

[email protected] http://www.powerworld.com

2001 South First Street Champaign, Illinois 61820 (217) 384-6330 ext 13

PowerWorld’s Experience Using Real-Time Power System Models

Presented by: James Weber, Ph.D. Director of Software Development December 6, 2016

2

• PowerWorld Simulator – 1996 – Planning software focused on Bus-Branch Models

• PowerWorld Retriever – 2000 – Real-time visualization software – Many pilot projects with this worked by exporting a

bus/branch model from the EMS (RAW file) • This was not a sustainable model for customer

• PowerWorld Retriever – 2006 – ISO-New England started work on using the data already

managed in their Areva EMS tool • Cases only initially, but progressed to reading their EMS one-lines

– This was clearly the better approach and other real-time customers followed

PowerWorld’s History of Full-Topology Models

3

• Data Definitions – How are objects uniquely identified – How is data structured

• Tools to Manage Increased Model Size – Previously simple concepts getting more complicated

• When is a line open? • Single Line Contingency

• Human Interaction – My model is huge – Data viewing – Data reporting

• Data Formats – Need to read information directly from the sources that manage

the full topology models

Our Experience: Four Types of Issues

4

• Depends on the time frame of your analysis – Past Event Replication Studies – Real-Time Studies – “Operations Planning”

• Looking at the next 24 hours • Looking at outage scheduling over the next several

months

– “Long-Term Planning” • Looking at next several years

Node-Breaker vs. Bus-Branch Which models are used?

5

Typical Existing Power Business Stages “State Mapping”

Long-term Planning (Bus/Branch) Operations Planning

(Bus/Branch) Real-time Operations

(Node/Breaker)

Dynamic (Bus/Branch)

Model Exporter

NOW FUTURE

Day – Months Years into the Future

Past Event Replication

Real-Time

PAST

Auxiliary Data

Operations Planning

System State Replicator

• Mostly Manual process to replicate the system state

• Full Time Staff ($$$) • Error-Prone

System State Replicator

• Mostly Manual process to replicate the system state


Contingency Definitions Transient Stability Data Generator Cost Data Flowgate Definitions Monitoring Information Visualizations

6

Typical Existing Power Business Stages “Auxiliary Data Mapping”



(Node/Breaker)

Model Exporter

Day – Months Years into the Future Real-Time


Auxiliary Data

Past Event Replication

Operations Planning

NOW FUTURE PAST

Dynamic (Bus/Branch)

This model is slightly different EVERY time it’s exported

Map Auxiliary Data

• 90% automated, but 10% manual to map auxiliary date


Map Auxiliary Data

• 90% automated, but 10% manual to map auxiliary date


Auxiliary Data mapping is slightly different EVERY time

7

A Better Choice for Operations Planning



(Node/Breaker)

Model Copier

Day – Months Years into the Future Real-Time Past Event

Replication Operations

Planning

NOW FUTURE PAST

Real-time Operations (Node/Breaker)

Map Auxiliary Data

• Infrequent updates to mapping

• Only when substations are changed

• Little staff time (¢¢¢) Auxiliary Data mapping changes infrequently and incrementally


Auxiliary Data

8

• The starting point for this is the system state stored in an EMS system or equivalent. – Or you must match another model to this – The model with the disturbance state is the full-

topology real-time model

• To use this model for studies, there is a lot more than just the model to maintain

Near Real-Time Analysis of the Power System

9

• Large amount of Auxiliary Information to maintain – Contingency Definitions – Interface/Flowgate/Path/Cutplane definitions – Limit Monitoring information

• What to monitor, dynamic limits, etc… – Market cost/bid information – Transient Stability Models – Various other groupings

• Injection Groups/Subsystems • Substations

– Graphical Visualization Descriptions

“Model” maintenance: It is more than just the model

10

Use Alphanumeric Identifiers: Labels

• Unique identifiers for all power system objects • Change infrequently or not at all • Independent of topology changes

– Bus numbers can change with each model export even if the only change is a breaker status

– System upgrades may change where a line is connected, but its identifier should not have to change (it might, but should not be required)

• Can be used with all auxiliary data: contingency definitions, interfaces, etc.

• Created automatically from Real-Time Model object identifiers – Typically with a real-time system there will be some unique identifier

Substation$RecordType$EMS_ID

– BrownsFerry$UN$Unit2 Generator – Johnsville$500$1928 500 kV node

11

• First instinct this is only a “naming” issue – Just build an “Automated Conversion Tool” that links

the names from the full-topology model to the names in the planning model

– In other words: Use Labels • This instinct is not correct. It is more than this.

– The models are different – Breaker topologies matter – Can not assume that all breakers are in their normal

status – Taking a line out of service depends on the present

system state

Are Labels enough? NO! Models are Different

12

Invalid Contingency Simulations Example 1

13


• How is outage of Line A modeled on following slide? – Planning Model

• Open Line A

– Actual System • Open breakers a1, a2, and b1

– Assuming all breakers have same status as original configuration from which planning case was created, then this is a correct simulation in planning case

14

• Now what happens when Line A is taken out of service?

Breaker a4 Out for Maintenance

15


• How is outage of Line A modeled along with open breaker a4? – Planning Model

• Open Line A • No other lines are isolated • Bus split not captured

– Actual System • Open breakers a1, a2, and b1 • Line D isolated from Line B and Line C

– Modification of planning model is required to correctly model this condition

16


Line D isolated from Line B and Line C

17

Breaker Failure Outages Example 3

• Problem – How to you model a breaker failure if you have

consolidated the breaker in the process of creating the planning model?

• Solution – Do not consolidate your data, let the software do

that as needed – To make contingency definitions more familiar, add

a new action called Open with Breakers

18

• Answer: No, you can NOT make a completely automated conversion tool

• A bus-branch model is inherently an “equivalent” representation of the breaker-node model – You have lost information by creating the bus-

branch model – You can’t just convert back to something that’s not

in the model now.

Can you make an

Automated Conversion Tool?

19

• Substation Definitions – The fundamental data structure in an real-time

model – Part of the unique identifier of a device – You must have this to make interaction with the

full-topology model easier • Define a list of substations • Assign each “bus” to a substation

– Natural place to define geography (Latitude, Longitude)

Important Data Structure Parts: Substations

20

• Planning models already have the concept of distinct types of branches – Line, Transformer, Series Cap

• Need to add branches that represent switching devices which have no impedance – At a minimum add Breaker, Load Break Disconnect, and

Disconnect • Used in “Open or Close with Breakers” features discussed

shortly • Used in “Derived Status” concepts discussed shortly

– May want to add Fuse, Ground Disconnect and ZBR for informational purposes as well

Important Data Structure Parts: More Branch Types

21

BranchDeviceType

22

• Don’t get hung-up on the terms “Bus” and “Node” – Both represent a point where devices connect – PowerWorld clobbers the nomenclature a little as we chose

to adopt the term “Bus” to mean the point where things connect. Thus for us it’s more like a “Node”

– We introduce the term “Superbus” to represent a definition that is internally managed by the software

• A Superbus represents a grouping of buses that are all connected by closed switching device branches

• It is similar in concept to an electrical island – Islands are added and removed in the software as branches change status – An Island represents a grouping of buses that are all connected by closed

branches of any type

Concept of a “Bus” and a “Node”

23

• Some data definitions go away – Idea of a “Line Shunt” as compared to a “Bus Shunt” is

unnecessary • All shunts are modeled with a connection to a bus • Line vs. Bus Shunt just depends on which side of the line

breaker it is connected. – Idea of a “Multi-Section Line” is unnecessary

• Software can automatically traverse the topology to determine which branches get isolated by the same set of breakers

• “Open with Breakers” option discussed next – Many Contingency Definitions go away

• Similar to multi-section line, just use the “Open with Breakers” option

Good News:

24

• In real-time systems, sometimes the generator station load is not modeled explicitly. – May not have separate measurements for generator

output and station load – This will be a problem if trying to do some types of

analysis (Transient Stability) – Example of where additional detail in “planning” model

may need to be pushed into the real-time model

Generator Station Load

25

• Bad News – In a real-time model these can get very

complicated and confusing • A “Single Line Outage” turns into 4 different breakers

opening together • The breakers necessary to isolate a line change as system

topology changes

– We need a better way to define a contingency

• Good News – We can model a breaker failure easily now

Contingency Definitions

26

• Open a device using breakers instead of changing the status of the device directly

• Ensures that accurate modeling of real-time system is achieved

• Automatically determine Breakers (or Load Break Disconnects) that need to open to isolate an element

• Breaker failure scenarios can be modeled by applying this action to a breaker

• Same idea for a “Close with Breakers” action

“Open with Breakers” and “Close with Breakers” Contingency Actions

27

Ability within User Interface to instruct “Open Breakers to Isolate”

28

• Traditionally Topology Processing is a separate tool which creates 2 separate models – Results in a data mapping issue – Prevents the novel use of concepts like “Open with Breakers” to

handle breaker failure modeling • PowerWorld’s Suggestion: completely integrate the concept

of topology processing inside the software algorithms • Each algorithm consolidates in a manner appropriate to it

– Power flow solve directly on the full-topology model (internally consolidate the power system model as necessary)

– Contingency analysis (only consolidate as necessary) – PV Curve and QV Curve behave differently – MW Linearized Tools (ATC, Sensitivity tools, etc…) behave

differently

Integrated Topology Processing

There is now only ONE model. So don’t get hung-up on the terms “Bus” and “Node” anymore.

29

• Buses (Nodes) = 77,146 – 16,496 Superbuses

• 4,059 disconnected • 12,437 connected

– 11,927 Subnets • Branches = 90,745

– 10,659 Lines – 197 Series Caps – 5,020 Transformers – 30,687 Breakers – 42,902 Disconnects – 399 ZBRs – 431 Fuses – 426 Load Break Disconnects – 24 Ground Disconnects

Peak Real-Time Models are Huge Human

This is 4-year old data. Latest Peak cases are >100,000 nodes Note: We have seen a MISO case that was more than 200,000 nodes

30

• To the right is a redacted detail of what the topology of the 500 kV bus at Grand Coulee

• It’s a Breaker and a Half configuration

• This would be a single bus in a “planning case”

Model Detail

31

• Model Navigation Obstacle – Can be confusing to navigate full-topology models

• Tools that graphically show bus-to-bus connections in the model can get very complicated – You can get stuck inside all the disconnects and

breakers – Makes finding more important devices difficult

(lines, transformers, generators, loads)

Human Interaction

32

Planning Case Bus View Bus: COULEE (40287)Nom kV: 500.00Area: NORTHWEST (40)Zone: Central Washington (403)

CHIEF JO CKT 1

COULE R1

BELL BPA

CKT 6

HANFORD CKT 1

MS

SCHULTZ CKT 1

MSCKT 2

MS

COULEE19

COULEE19

CKT 1

COULEE20

COULEE20

CKT 1

COULEE21

COULEE21

CKT 1

COULEE22

COULEE22

CKT 1

COULEE23

COULEE23

CKT 1

COULEE24

COULEE24

CKT 1

COULEES2 CKT 1

A

M VA

A

Am ps

A

Am ps

A

Am ps

A

Am ps

A

Am ps

A

Am ps

A

Am ps

A

Am ps

A

Am ps

A

Am ps

A

Am ps

COULEE

1.0800 pu540.00 KV 59.94 Deg 0.00 $/MWh

0.00 MW 0.00 Mvar

218.6 MW 22.8 Mvar 219.8 MVA

402331.0800 pu540.00 KV

40288

37.4 MW 143.0 Mvar 147.8 MVA

400911.0893 pu544.65 KV

1244.3 MW 34.0 Mvar1244.7 MVA

404991.0791 pu539.53 KV

1264.9 MW 77.6 Mvar1267.3 MVA

409571.0813 pu540.66 KV

1264.9 MW 77.6 Mvar1267.3 MVA

41739

0.0 MW 0.3 Mvar 0.3 MVA

402911.0035 pu 15.05 KV

41740

545.0 MW 38.1 Mvar 546.3 MVA

402931.0198 pu 15.30 KV

41741

549.9 MW 36.8 Mvar 551.2 MVA

402951.0197 pu 15.30 KV

41742

615.3 MW 48.6 Mvar 617.2 MVA

402961.0018 pu 15.03 KV

41743

629.9 MW 52.5 Mvar 632.1 MVA

402971.0013 pu 15.02 KV

41744

629.9 MW 52.5 Mvar 632.1 MVA

402981.0013 pu 15.02 KV

1.0476 tap

548.0 MW 9.4 Mvar 548.1 MVA

413571.0342 pu237.87 KV

33

Real-Time Bus View • All Breakers and Disconnects

34

Consolidated Superbus View • Looks like the “planning case” essentially

35

Oneline Visualizations Must be Substation Based

36

• Adding ability to read substation topology onelines directly from the files maintained by the EMS modeling groups

Build Tools to Load Substation Topology Onelines

37

• EPC and RAW files: Historically represent “bus-branch” models, thought that is evolving

• HDBExport command from Areva EMS – A lot of experience reading from this EMS data

structure for many customers for a decade – Data structures are very similar to those used in

Bus/Branch models actually – Fundamental object is the Node (ND)

• ABB Spider EMS – Experience reading full cases for use in running

contingency analysis, but only with 1 customer • Siemens EMS

– Small amount of experience loading only the topology definition so that measurements could be mapped

• OpenNet EMS – Very small amount of experience

Experience with other Data Formats

38

• Hdbexport command gives users of this EMS the ability to export data – We have 10 years of experience reading the network

model – Also have experience exporting the Contingency and

RAS definitions using similar methodology • Oneline diagrams format is also text-based and

links to these case – We can read these diagrams into PowerWorld as well – Some work up-front to translate how things are drawn

as this is custom for every Areva customer

Experience with Areva EMS

39

• Data • Tools • Human Interface • Interfacing with other Data Structures

Experience

Restricted © Siemens Industry, Inc. 2014 All rights reserved. Answers for infrastructure and cities.

Node-Breaker Modeling in PSS®EJoe Hood

Siemens Power Technologies International

03-19-2014

Restricted © Siemens Industry, Inc. 2014 All rights reserved.

Page 2 Siemens Power Technologies International

Node-breaker Modeling in PSS®EKey Points

• Available in Version 34• Further improvements and integration into various analyses with later minor releases

• Unobtrusive Implementation• There when you need it, but out of the way when you don’t want it• We don’t want to lose the very useful concept of the traditional “bus”

• Full Integration into SAV and RAW formats• New data records attached to end of RAW file• No changes needed to existing data records to add Node-breaker topology

• Automatic Substation Node-breaker Topology Building• One-click process for building initial-pass topology directly from single line diagram

based on common arrangements (1 ½ breaker, double breaker, ring bus, etc.)• Substation Node-breaker single line diagrams drawn automatically

03-19-2014



Methodology

Traditional Network Data

Node-breaker Data(optional)

Internal Network Model

TopologyProcessor

SLDs

AnalysisEngines

(PF, ACCC, GIC, OPF, SC, etc)

API

03-19-2014



PSS®E Bus-Branch to Node-Breaker Mapping

03-19-2014



Substation/Node/Bus Mapping

Substations BusesNodes

11

1

∞ ∞

∞

Key: Sub IDKey: (Sub ID, Node ID)

Key: Bus ID

03-19-2014



Branch Mapping

Node NI

Node NJ

Bus I

Bus J

(I, J, CKT)

Branch/2-winding Connection Record: (I, J, CKT, NI, NJ)3-winding Connection Record: (I, J, K, CKT, NI, NJ, NK)

03-19-2014



Terminal Device Connection Mapping

Node N1

Bus I

(I, MACHID)

Connection Record Format for All Device Types: (I, ID, NI)

03-19-2014



Mapping Example

1

2

34

5

6

7

8

9 10

(101, 102, ‘1’)

101

102

Substation 1

(101, ‘1’)

03-19-2014



Topology Processor

The topology processor takes substation switching device connections and statuses as inputs to group the nodes into electrically connected bus sections, assigning a topological bus for each group, and moving components to the right topological bus.

Internally, the topology processor will:

• Check for connectivity errors in the bus-branch model and substation models• Generate node groups by locating all nodes which are connected together by

closed circuit breakers and disconnect switches.• Assign a topological bus to each group, create a bus-section and re-route

components to the bus as needed.• Form into electrical "islands" all of the buses connected together by AC lines,

including transmission lines, and transformers. An island must have at least one system swing bus

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Bus-branch SLD to Substation Node-breaker Model Navigation

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Isolate by Breaker Operation

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PSS®E 34.1 - Node-Breaker Contingency Definitions

The following new Contingency Definitions have been added:

• ISOLATE a single end of an in-service branch, system switching device or two-winding transformer by breaker operations

• ISOLATE a single terminal of an in-service three-winding transformer by breaker operations

• Place a closed breaker in the status of “stuck”. It will fail to open in subsequent isolation operations in that contingency

• Create contingencies for every in-service branch or transformer connected to a bus

03-19-2014



PSS®E 34.1 - Node-Breaker Contingency Definitions

The following new Contingency Definitions have been added:

• Create contingencies for every in-service branch or transformer in a subsystem

• Create contingencies for every in-service substation switching device (which can be limited to switches or breakers) in a subsystem

• Create stuck breaker contingencies for a subsystem. For each substation in the subsystem, for each node in that substation, all combinations of in-service branches or transformers and closed breakers connected to that node will be found. Each combination will generate a contingency consisting of a stuck breaker record for that breaker and an isolate record for that branch or transformer.

03-19-2014



PSS®E 34.1 – Node-Breaker Data APIs

• Node-Breaker Subsystem Fetch routines• aStationCount, aStationInt, aStationReal, aStationChar,aStationTypes• aStaSwDevCount, aStaSwDevInt, aStaSwDevReal, aStaSwDevCplx,

aStaSwDevChar, aStaSwDevTypes• aTerminalCount, aTerminalInt, aTerminalChar, aTerminalTypes• aNodeCount, aNodeInt, aStationChar, aNodeTypes

• Node-Breaker Individual Fetch routines• GenSectDat, GenSectDt1• IniStaBusSect, NxtStaBusSect, StaDat, StaInt, StaName• IniStaNode, NxtStaNode, StaNodeInt, StaNodeName• IniStaSwDev, NxtStaSwDev, StaSwDevDat, StaSwDevInt, StaSwDevName• BusSectDat, BusSectDt1, BusSectDt2, BusSectExs, BusSectInt

• Following now return Node-Breaker values• BRNINT, FXSINT, LODINT, MACINT,SWSINT, BUSINT

03-19-2014



PSS®E 34.1 – Node-Breaker Station Layout Editor

Modifying node locations and attachments

Allows the user to specify the location of a node relative to the center of all nodes associated with the node’s bus.

All nodes of a particular bus can be shifted together relative to the center of the station.

Grid spacing used when assigning positions. May be multiples of grid spacing if smallest node distance is large.

Node connections and attached equipment can be modified from dialog by selecting the corresponding [Edit] button.

03-19-2014



RAW Format Extension

Substation Data Block Substation Data Block Substation Data Block Substation Data Block

…

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Node-breaker RAW Data Example

@! BEGIN SUBSTATION DATA BLOCK@! IS, 'N A M E' , LATITUDE, LONGITUDE, SGR

1,'RISING_HERCULES_SERVES_ALL_SUB_STATION_1', 33.6134987, -87.3737030, 0.1100@! BEGIN SUBSTATION NODE DATA@! NI, 'N A M E' , I,STATUS

1,'RISING_HERCULES_SUB_STATION_1_____NODE_1', 101, 12,'RISING_HERCULES_SUB_STATION_1_____NODE_2', 101, 13,'RISING_HERCULES_SUB_STATION_1_____NODE_3', 101, 14,'RISING_HERCULES_SUB_STATION_1_____NODE_4', 101, 10 / END OF SUBSTATION NODE DATA, BEGIN SUBSTATION SWITCHING DEVICE DATA

@! NI, NJ,CKTID, 'N A M E' , TYPE,STATUS, NSTAT, X , RATE1, RATE2, RATE31, 3, '1 ','RISING_HERCULES_SUB_STATION_1_SSWD_1_3_1', 2, 1, 1, 0.00010, 0.0, 0.0, 0.02, 4, '1 ','RISING_HERCULES_SUB_STATION_1_SSWD_2_4_1', 2, 1, 1, 0.00010, 0.0, 0.0, 0.03, 4, '1 ','RISING_HERCULES_SUB_STATION_1_SSWD_3_4_1', 2, 1, 1, 0.00010, 0.0, 0.0, 0.00 / END OF SUBSTATION SWITCHING DEVICE DATA, BEGIN SUBSTATION TERMINAL DATA

@! I, NI, TYP, J, K, ID101, 4, 'M', '1 '101, 3, '2', 151, 'T1'0 / END OF SUBSTATION TERMINAL DATA

03-19-2014



Substation Record

IS Substation number (1 through 999997). No default allowed

NAME substation name, NAME may be up to twelve characters and may contain any combination of blanks, uppercase letters, numbers and special characters. NAME must be enclosed in single or double quotes if it contains any blanks or special characters. NAME is twelve blanks by default.

LATI Substation latitude in degrees (-90.0 to 90.0). It is positive for North and negative for South, 0.0 by default

LONG Substation longitude in degrees. (-180.0 to 180.0). It is positive for East and negative for West, 0.0 by default

SRG Substation grounding DC resistance in ohms

03-19-2014



Node Record

IS Substation number (1 through 999997). No default allowedNI Node number (1 though 99). No default allowed.NAME Node name, NAME may be up to twelve characters and may

contain any combination of blanks, uppercase letters, numbers and special characters. NAME must be enclosed in single or double quotes if it contains any blanks or special characters. NAME is twelve blanks by default.

I Topological Bus number (1 though 999997) in bus branch model. The electrical bus represents this node NI and others that are connected by closed switching devices.

STATUS Node status. One for in-service and zero for out-of-service, one by default.

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Connection Device Record

IS Substation number (1 through 999997). No default allowedNI From node number (1 though 99). The from node must be in the

substation IS. No default allowed.NJ To node number (1 though 99). The to node must be in the substation

IS. No default allowed.CKTID two-character uppercase non-blank alphanumeric switching device

identifier; CKT = 1 by default.NAME Switching device name, NAME may be up to 12 characters and may

contain any combination of blanks, uppercase letters, numbers and special characters. NAME must be enclosed in single or double quotes if it contains any blanks or special characters. NAME is 12 blanks by default.

TYPE C - Circuit breaker, S - Disconnect switch, Others..

STATUS Switching device status. one for close and zero for open; ST = 1 by default.

NSTAT Switching device normal status. one for close and zero for open; ST = 1 by default.

X Switching device reactance; entered in pu. A non-zero value of X must be entered for each switching device. 0.0001 by default

RATE1 First rating; entered in either MVA or current expressed as MVA.

RATE2 Second rating; entered in either MVA or current expressed as MVA.

RATE3 Third rating; entered in either MVA or current expressed as MVA.

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Branch/Two Winding Connection Record

I From bus number. No default allowed.

J To bus number. No default allowed.

CKTID two-character uppercase non-blank alphanumeric switching device identifier; CKT = 1 by default.

NI From node number (1 though 99). If the electrical from bus has node breaker model, in other words it represents a set of nodes in a substation, the from node must be one node in the set and indicates the connections of branch within the substation. If the electrical from bus has no node breaker model, it is zero. No default allowed.

NJ To node number (1 though 99). If the electrical to bus has node breaker model, in other words it represents a set of nodes in a substation, the to node must be one node in the set and indicates the connections of branch within the substation. If the electrical to bus has no node breaker model, it is zero. No default allowed.

03-19-2014



Load Connection Record(Representative of Terminal Device Connection Records)

I bus number. No default allowed.

ID One- or two-character uppercase non-blank alphanumeric load identifier used to

distinguish among multiple loads at bus I. It is recommended that, at buses for which

a single load is present, the load be designated as having the load identifier 1. ID = 1

by default.NI node number (1 though 99). If the electrical bus has node

breaker model, in other words it represents a set of nodes in a substation, the node must be one node in the set and indicates the connections of the load within the substation. If the electrical bus has no node breaker model, it is zero. No default allowed.

03-19-2014



Automatic Substation Building

03-19-2014



Interacting with Node-breaker Model

• Open/close breakers in SLDs• Edit data in network data grids• Manipulate via APIs• Soon to be incorporated in

CON/MON/SUB syntax, RAS definitions, etc

03-19-2014



Joe Hood, MSEE, PEProduct Manager, PSS®ESiemens PTI

Phone: +1 (803) 397-8539

Email: [email protected]

Questions?

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ETAP HeadquartersSales & Support Offices

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© 2016 ETAP

Design & Analyze Utility Transmission Systems

Planning & Optimization Intelligent One-Line Overcurrent

Protection Distance Protection

User-Defined Dynamic Models Substation Grounding Transmission

Equipment Modeling

© 2016 ETAP

Integrated Solution

Geospatial Intelligent Diagram

Voltage Stability

Renewable Energy

Dynamics & Transients

Unified AC & DC

Power Flow

© 2016 ETAP

Integrated Solution

NERC MOD Compliance

DPET

User-Defined Dynamic Models

Contingency Analysis

Unbalanced Short Circuit

Optimal Power Flow

© 2016 ETAP

Quality Assurance

Standards• ISO 9001• 10 CFR 50, Appendix

B• 10 CFR 21• ANSI/IEEE 730.1• ANSI N45.22• ANSI/ASME N45.2• ASME NQA-1• CAN/CSA-Q396.1.2

Matured QA Program Since 1991

Verification & Validation (V&V)

• Interface

• Calculation Engines

• Industry accepted Equations

• Field Measurements & Software Benchmarks

• Engineering Libraries

• Pass multiple audits per Year

Benchmark of the Industry

© 2016 ETAP

• Entire CPU memory

• Video card memory

• Multi-CPU cores

• View & analyze millions of components

• Hi speed computation

Solution Speed, A True 64-Bit Software

Take Advantage of Latest Technologies

© 2016 ETAP

“Node-branch”, offline planning studies, limited topological data representing the physical configuration (source: mainly NERC & WECC):

• Majority of offline planning studies use bus-branch models to represent power system networks

• Models typically represent each substation with a single bus at each nominal voltage level

• Without knowledge obtained outside the represented bus-branch model, it is not possible to determine the substation breaker configuration and how it operates during contingencies

• The primary limitations have been in the simulation of breaker-to-breaker clearing of faulted sections of the system (potentially multiple branches) and in the evaluation of the physical configuration.

General Node-branch issues?

© 2016 ETAP

“Node-branch” offline planning studies, issues continue:• Since breakers are not explicitly modeled, therefore, no

topological impacts of alternative station configurations, etc. • Real-Time Contingency Analysis (RTCA) studies is not consistent

with planning model and produces conflicting solutions.• Not having Consistencies in model parameters between its

planning model and its RTCA model. • Coordinating the effect of protection systems during

contingency scenarios.• Studies also do not consider a full list of internal and external

contingencies that could impose limitations on their daily operations or external operations.

General Node-branch issues?

© 2016 ETAP

“Node-breaker” modeling greatly improves: (source: mainly NERC & WECC)

• Visibility of equipment status (e.g. showing case-specific switch and breaker statuses).

• Station configuration and topology changes within substations by changing the status of switching devices (e.g., bus splitting).

• Associated critical contingencies.• Simulation of protection system operation.• Identification of operating capabilities industry-wide.• Associated operating and planning assessments.• Model validation from PMU data or system disturbances.

Why changing to node-breaker approach?

© 2016 ETAP

“Node-breaker” major topology and benefits……..• More accurate representation of the transmission system.• Recognizing split buses/stations and multi-terminal lines.• Reduced number of errors in defining and processing

contingencies. • Allow analysis of individual busses and equipment nominal

capacity.• Allowing to utilize compatible data sets to be used for real-

time operational studies and planning studies.• Facilitation of model benchmarking to real-time conditions.

Why changing to node-breaker approach?

© 2016 ETAP

Several are listed below:(source: mainly NERC & WECC)

• Topological processing:• Ability to determine which breakers are needed to isolate.• Automated contingency analysis.

• Capability of applying “node-breaker” representations on a station by station basis.

• Ability to reduce “node-breaker” detail to a “bus-branch” representation for selected stations.

• Ability to specify a “node-breaker” or a “bus-branch” view of the data and solution.

• Ability to find a power flow solution in a timely manner. • Graphical user interface designed for building node-breaker

substation using drag and drop capabilities.

Requested new or improved software capabilities

© 2016 ETAP

ETAP Capabilities and its flexible functionality:• Single platform for modeling, design, analysis, &

operation of electrical systems. • Modularized & integrated software capabilities designed

to meet current & evolving standards.• Handle very large electrical systems with millions of

components with fast speed. • Unlimited configurations and revision data to create

breaker-to-breaker details model.• Capability of applying “node-breaker” representations

and scheme on a station by station basis.

Why ETAP for node-breaker modeling approach?

© 2016 ETAP

ETAP Capabilities continue:• Ability to determine which breakers will open (in

chronological order) based on the actual fault current.• Ability to view and analyze of the data and results

automatically.• N-1 & N-2 capability to perform contingency analysis.• Streamline between ETAP load-flow, short-circuit, and

protective device coordination modules.• Data exchange, Import & export, capability between many

existing software platforms. • ETAP real-time and data conversion to off-line planning

model.

Why ETAP for node-breaker modeling approach?

© 2016 ETAP

ETAP Sample Model

Utilizing one model/database to perform:- LF Study- SC Study- Protection & Coordination- Contingency Evaluation- And more

Modeling Bulk Electric System:- Generation- Transmission- Distribution

This SLD is only for presentation purposes

Composite network to model each system/sub-station (nested)

© 2016 ETAP

Line & Protective Devices

• Available different sub-station model templates, transmission line, loads, transformers, capacitors, switches, PDs/relays, and more.

• Project merge: performing modeling by more than one engineer the same time .

© 2016 ETAP

Substation Templates & Circuit Continuity

© 2016 ETAP

Unlimited system topology

Gen1 is off

Two CB opens, splits substation C in two.

© 2016 ETAP

Power Flow

Load flow result, MVA, and bus voltage profile for the specific configuration.

© 2016 ETAP

Unified AC & DC Time Series Power Flow

© 2016 ETAP

• N-1 and N-2 Contingency Assessment & Ranking

• Multiple Graphical Outage Lists

• Fast Screening MethodØScan outage list Ø Identify higher risk

contingencies for further evaluation

• Automatic Performance Indices CalculationØBus voltage securityØReal power flow changeØReactive power flow changeØBranch overloading

N-1 & N-2 ContingencyAnalyze & visualize thousands contingencies in minutes

© 2016 ETAP

• Compare & analyze study results for both LF & SC

• User-defined base-line / reference

• Worst-case results scenarios

• Comprehensive results in different formats

• Extensive data manager for input and output

View results of multiple studies in one glance

Report & Analyzer for LF & SC

© 2016 ETAP

• The sequence-of-operations automatically performs a complete set of actions to determine the operation of all protective devices by placing “Fault Insertion” at interested point.

• Display / flash the tripped devices in chronological order on the one-line diagram.

• Determine the operating time and state of all protective devices based on the actual fault current contribution flowing through each individual device.

• Faults type: 3Ø, L-G, L-L, and L-L-G.

Star, Protection & CoordinationSequence of Operation (SQOP)

Arcing Fault & Bolted Fault

© 2016 ETAP

Distance Protection

§ Intuitive distance relay characteristic coordination

§ Easy-to-use graphical user interface§ Graphical tool for setting verification &

protection coordination§ State plot to validate PD settings &

scheme logic§ PD Sequence-of-Operation

© 2016 ETAP

Unbalanced Sliding Fault

§ Intuitive distance relay characteristic coordination

§ Easy-to-use graphical user interface

§ Accurate & realistic distance relay modeling

§ Extensive relay model library

© 2016 ETAP

• Automatic detection of zones of protection & coordination

• Automatic detection of worst case fault location

• Automatic evaluation throughout the system

• Display warnings & alarms

• Display TCCs to prove conclusions

• IEEE & IEC evaluation rules

• Customizable rule books

Star Auto-Evaluation

Reduce Man-Hours from Months to Minutes

© 2016 ETAP

Modeling, Analysis, Monitoring, Optimization, Automation, Operation

Modeling to Operation

© 2016 ETAP

• SCADA & Monitoring

• Power Management

• Transmission Management

• Substation Automation

• Generation Management

• Microgrid Master Controller

• Intelligent Load Shedding

• Advanced Distribution Management

ETAP Real-Time

Model-Driven Real–Time Solutions for Power SystemsFully integrated suite of software products that provides mission critical power

management solutions.

© 2016 ETAP

Integrated Transmission Management System

eSCADAAutomatic Generation

Control

Economic Dispatch

Unit Commitment

Interchange Scheduling

© 2016 ETAP

ETAP Real-Time, PMSpowerful analytical tools that allows for detection of system behavior in response

to operator actions and events via the use of real-time and archived data.

ETAP real-time model can be converted into off-line model for planning study.

ETAP can import several formats such as Multispeak and CIM, which are common interfaces for EMS systems, into off-line planning model.

© 2016 ETAP

ETAP Real-Time, EMS

Energy Management System applications are designed to reduce energy consumption, increase electrical system reliability, improve equipment

utilization, and predict system performance, as well as optimize energy usage

© 2016 ETAP

ETAP Real-Time, iSUB

• Intelligent Substation is packaged as a focused product for substation automation.

• iSub provides protection, control, automation, monitoring, and communication capabilities

© 2016 ETAP

ETAP Real-Time, Microgrid

Microgrid Master Controller allows for design, modeling, detailed analysis, islanding detection, optimization and automated control of Microgrids used for offices, industrial facilities, data centers, campuses, offshore facilities, ships, etc.

© 2016 ETAP

• Legacy database conversion to ETAP

• Aspen, PSS/E® (RAW, SEQ, DYR files import)

• CYME, SKM PowerTools®, ESA

• Common Information Model (CIM)

• EMTP-RV®, PSCAD® / EMTDC® interface

• Excel® and Access interface

• ESRI ArcGIS®, Intergraph G/Tech

• And more….

Data exchange & conversionCustomizable universal mapping & interface

Data and Model Conversions

Modeling Bulk Electric System:- Generation- Transmission- Distribution

© 2016 ETAP

QUESTIONS?

ETAP PresentersZia Salami – [email protected]

Tanuj Khandelwal – [email protected]

Use of Node-Breaker Model in POM Suite/ROSE Software

Marianna Vaiman, V&R [email protected]

NERC Node – Breaker WebinarDecember 5, 2016

Copyright © 1997-2016 V&R Energy Systems Research, Inc. All rights reserved.1

Contents

1. POM Suite and ROSE Application2. Using State Estimator Case Node-breaker Model for

Real-Time and Off-Line Analyses3. Creating a “Hybrid” Node-Breaker/Bus-Branch Mode

Using a Planning Case4. Inserting Real-time Data into a Planning Case

4.1 Inserting State Estimator Case into a Planning Case4.2 Inserting Historical Real-Time Measurements into

a Planning Case

2Copyright © 1997-2016 V&R Energy Systems Research, Inc. All rights reserved.

Copyright © 1997-2016 V&R Energy Systems Research, Inc. All rights reserved. 3

1. POM (Physical and Operational Margins) Suite and ROSE

(Region Of Stability Existence) Application

POM Suite – Planning

POM - Physical and Operational MarginsOPM - OPtimal Mitigation MeasuresBOR - Boundary of Operating RegionPCM - Potential Cascading ModesScriptHelper - POM-ScriptHelper

TS - POM-Transient StabilityOPMTS - OPM Transient StabilityPCMTS - PCM Transient StabilitySA - POM Small-Signal Analysis


POM Suite Use in PlanningNERC-compliance studies:– NERC TPL TPL-001-4

Steady State AnalysisStability Analysis

– NERC CIP-014-2 Standard CompliancePhysical Security

– NERC FAC-014 Standard ComplianceEstablishing System Operating Limits

– NERC PRC-023 Standard ComplianceIdentification of 100kV- 200kV transmission lines

– NERC MOD-001, 004, 006, 007, 008, MOD-028, 029, 030Available transfer capability

Voltage stability analysis:– AC transfer/load pocket and contingency analyses

Determines available transfer capability for each contingencyComputes interface flowsAutomatically builds PV/QV-curves


ROSE SoftwareModel-based, measurement-based & hybrid State Estimator– Can use V&R’s SE or export from any

EMS vendor

Model-based and measurement-based analysisIntegrated voltage and transient stability analysesReal-Time Phase Angle Limit computation and monitoringBoundary-based solutionAutomatic analysis of cascading outagesAutomatic remedial actions


ROSE CapabilitiesConventional, Hybrid and Linear State Estimation;Power flow;Real-time AC contingency and cascading analysis:– N-1, N-1-1, N-2 AC contingency analysis– Fast Fault Screening– Automated analysis of cascading outages

Real-time Phase angle limit computation and monitoring;Automatic corrective actions:– Automatic optimal corrective actions to alleviate steady-state violations;– Automatic optimal corrective actions to alleviate transient stability violations;– Modeling of complex user-defined RAS actions.

Voltage stability analysis:– Flexible scenario definitions;– 1-D and 2-D analysis;– In terms of MW flows on the interfaces or phase angles;– Alarming and visualization.

Boundary-based solution;Transient stability analysis.


ROSE FrameworkModel - based ROSE:– State Estimator data is required at the rate available at the entity using the

application, usually 3 to 5 minutes.

“Hybrid”- based ROSE:– Synchrophasor and State Estimator data sets are required:

Synchrophasor data at the rate available at the entity using the application, usually 30 samples/second.State Estimator data at the rate available at the entity using the application, usually 3 to 5 minutes.

Measurement - based ROSE:– Phasor data is required the rate available at the entity using the application,

usually 30 samples/second.


Role of the Node-Breaker Model in POM Suite/ROSE

Bridges real-time and off-line analyses Includes three different frameworks for using node-breaker model:– 1. Reading State Estimator case in node-breaker model:

Case can be saved as a node-breaker or bus-branch model;

– 2. Creating a “hybrid” model based on the planning case such that a part of the model is node-breaker and a part is in bus-branch model

– 3. Inserting real-time data into planning model:Inserting State Estimator Case into a Planning Case;Inserting Historical Real-Time Measurements into a Planning Case.


Node-Breaker Model: ChallengesUsing node-breaker model leads to:– Larger cases (number of buses will increase);– Solving ill-conditioned Jacobian matrix.

The software that uses node-breaker model for computations should:– Be fast to perform contingency analysis (steady-state and

transient), transfer limit computations, etc. on larger cases;– Have robust solution engine;– Have capability to perform topology processing.


POM/ROSE Integration with Other Applications

Reads both node-breaker and bus-branch modelsNode-breaker:– Export (“flat”) file from an EMS system, e.g. West-Wide System

Model – used at Peak Reliability, SCE, SDGE, IPC– PowerWorld *.aux format – used at BPA, ISONE– CIM XML

Bus-branch:– Power flow cases in PTI PSS/E rev. 26-33, GE-PSLF version 18 (and

earlier), PowerWorld *.aux format, common data format (.cdf)

Solves and converts cases to POM internal formatModified power flow cases may be saved for future use



1. Using State Estimator Case in Node-Breaker Model for Real-

Time and Off-line Analyses

Using Node-Breaker Model in POM Suite/ROSE

POM Suite/ROSE analysis includes:– Reading of State Estimator (SE) case in node-breaker model – Performing necessary topology processing– Performing steady-state analysis:

Voltage stability analysis, N-1, N-2, N-1-1 AC contingency analysis, cascading analysis, RAS implementation, determining remedial actions, etc.

– Performing transient and small-signal stability analysis– Automatic conversion of the node-breaker model to bus-branch

model


14

Peak-ROSE Application Architecture

Archive

Client

Filelink Apps

Output Data in .csv Files

VSAPOMROSE

SE Case

RAS Arming Points

EMS(SE &

SCADA)

PI Historian

15

WSMExport file copy

RTNET SaveCase

WSMExport_temp.csvSPMEAS_temp.csv

EMS V&R

WSMExport.csvSPMEAS.csv

Input Folder

Work Folder

WSMExport.csvSPMEAS.csv

Checks to see if file exists in Input Folder every 100ms

Waits for 1s and then copy Run

VSA

WSMExport_temp.csvSPMEAS_temp.csv

Rename

16

Peak’s Implementation of the ROSE-Filelink API

Use of Node-Breaker Model for Steady-State Stability Analysis in Peak-ROSE

Peak-ROSE is used for steady-state analysis in real-time and off-line environments, including:– Voltage stability analysis:

Runs multiple user-defined scenarios;Computations performed for each scenario are:– Determining interface limits;– Performing PV-curve analysis;– Performing VQ-curve analysis.

– Automatic AC contingency analysis;– Reading of existing real-time RAS;– Topology processing;– Satisfies Cyber Security requirements.


18

Peak’s Visualization

19

Peak-ROSE Engineering UI in Real-TimeResults of model-based computations

PMU measurements

Scenario summary and alarming

Copyright © 1997-2016 V&R Energy Systems Research, Inc. All rights reserved.

Use of Node-Breaker Model for Cascading Analysis in ISONE ROSE-PCMSteady-state analysis of fast developing cascading events when Operator has no time to reactComprehensive modeling capability to handle real-life size EMS node-breaker model– Topology Processing– Multi-threaded calculations– Satisfies Cyber Security requirements

Integrated with ISO-NE EMS

20

Source: Eugene Litvinov, ISONE

Process of PCM Analysis

21

Figure. Source: Eugene Litvinov, ISONE

On-line ROSE-PCM GUI

22

Source: Eugene Litvinov, ISONE

Displaying Node-Breaker Model in POM Suite/ROSE

After export “flat” file is being loaded, it is displayedin the form of:– POM Data Tables;– One-lines that are automatically built.

Different options to view/group elements:– Using various filters– Using tree-type view (by kV, by equipment, etc.)



RAS Actions in Peak-ROSERAS actions in Peak-ROSE are breaker-orientedRAS are automatically triggered provided that certain triggering conditions are met and arming status is enabled (where available)Breaker-oriented contingencies may be executed with or without RAS– A user-defined option

RAS actions implemented are:– Event Based;– Condition Based;– Combination of Event Based and Condition Based.

Use of Node-Breaker Model for Determining Remedial Actions

Remedial actions may be further developed to:– Alleviate post-contingency violations

Voltage stability, voltage, thermal– Increase operating margins



2. Creating a “Hybrid” Node-Breaker/Bus-Branch Model

Using a Planning Case

Station Bus RepresentationMost Planning Models represent substations as single buses:– The representation of contingencies requires knowledge

of the station configuration; this information is not included in the bus-branch model

The Impact of Split buses is not automatic, and the model must be manually updated – takes time, prone to errorTopology must be re-processed manually after a split busWhile N-1 contingencies represent a small amount of effort, N-1-1 contingencies increase this effort significantly


Node-Breaker Topology Representation of Con Edison’s Stations for Planning Studies

A “hybrid” model was developed in a project for Con Edison’s footprint:– Stations are modeled using a node-breaker model – Other elements are represented by a bus-branch model

Implementation of a node-breaker representation at all voltage levels in interconnection-wide planning power flow cases may be impracticalBenefits include:– An accurate realistic modeling of contingencies for NERC-

compliance studies;– Bringing real-time and planning models closer together.


Scope of Work: A Project with Con Edison

N-1-1 Contingencies must include Transmission Lines, Generators, Phase Angle Regulators, Transformers, and Bus Sections45 Transmission Stations with an average of 10 breaker-separated bus sections each, for a total of 450 unique bus sections200 transmission paths, 50 generatorsA Total of 700 N-1 Contingencies490,000 N-1-1 Contingencies


Framework for Combining the ModelsAn automated process to implement node-breaker capabilities for representing major stations within Con Edison’s footprint:– Capability of applying node-breaker representations on a station

by station basis;– Ability to obtain a power flow solution using the “hybrid” power

system model;– Performing automated contingency analysis using the node-

breaker information for the station with remedial actions.


Input Data for Creating Hybrid ModelPlanning power flow case in PSS/E .raw data format (may be in GE’s epc format)Bus station records:– Original buses – a list of buses (stations) that will be represented using node-

breaker model;– New buses – a list of additional buses, into which the original bus is split;– Switchgear list – a list of new switchgear with indication of New Switchgear

Code for new bus connectivity;– Branch list – a list of new switchgear that defines reconfiguration between the

existing network and additional buses;– Transformer list – a list of new switchgear that defines reconfiguration

between existing network and additional buses;– Shunt list – a list of new switchgear that defines shunt reconfiguration to a new

bus.


Creating a Hybrid ModelOriginal planning case is readBus station records are readStatus of switchgear is analyzedNew buses are added to the load flow case based on rules for numbering and naming conventionsNew switchgear/branches are added to the load flow caseNumbering of transformer windings is adjusted for each station– Reconfiguration of transformer windings is performed

Numbering of shunt devices is adjusted for each station– Shunt devices may be connected to a new bus

Topology analysis of the new “hybrid” system is doneInitial values of voltage magnitude and angle at new buses are computed


Automatically Creating a Breaker-Oriented Contingency List

Breaker-oriented contingency list is generated automatically, including:– All single breaker outages that have effect on

the system: For example, 14 and 15

– All double breaker outages that have effect on the system:

For example: (1,2), (1,3)

– Stuck breaker contingencies:For example: (1,3,5), (5,7,9), (8,10,14) and (4,6,15)

– Contingencies that split a bus:For example: (2,4) and (7,9)


Advantages of POM Bus Analysis (prepared by Con Edison)

Incorporation of automatic Topology Processing in the Contingency Analysis ProcessPost contingency remediationSatisfies accuracy, thoroughness, and documentation requirements for NERC compliance studiesHuge savings in preparation, analysis, and documentation timeAutomatic selection of unused bus numbers– All new numbers include the “original” bus number

Most Energy Control Centers already use a topology processor in their SCADA systems to ensure accurate results. – This effort will align Transmission Planning results with Operations

results



3. Inserting Real-time Data into a Planning Case

3.1 Inserting State Estimator Case into a Planning Case

Take a State Estimator (real-time) case Embed this real-time case into a planning modelPerform computations on the combined case (voltage stability, transient stability, transfer analysis, cascading outage analysis)


3.2 Inserting Historical Real-Time Measurements into a Planning Case

Take available real-time measurements from a historical databaseBased on these measurements and system parameters, perform state estimation, create a real-time case representing actual system conditionsEmbed this real-time case into the planning model in order to account for the following:– Global (e.g., interregional) phenomenon of cascading;– “Potential internal or external contingencies”.


Analysis Process

A real-time case created by POM State Estimator (POM SE) NYISO planning modelA combined real-time and planning model


Project with Con Edison:– Purpose –

more accurate contingency and cascading outages analysis

Thank you!


Confidential. Not to be copied, distributed, or reproduced without prior approval.

Node-Breaker Model in GE PSLF NERC Webinar

December 6, 2016

Brian Thomas Manager – GE PSLF and MARS [email protected] 518-385-4762

mailto:[email protected]

Confidential. Not to be copied, reproduced, or distributed without prior approval.

CAUTION CONCERNING FORWARD-LOOKING STATEMENTS:

This document contains "forward-looking statements" – that is, statements related to future

events that by their nature address matters that are, to different degrees, uncertain. For details

on the uncertainties that may cause our actual future results to be materially different than

those expressed in our forward-looking statements, see

http://www.ge.com/investor-relations/disclaimer-caution-concerning-forwardlooking-

statements as well as our annual reports on Form 10-K and quarterly reports on Form 10-Q. We

do not undertake to update our forward-looking statements. This document also includes

certain forward-looking projected financial information that is based on current estimates and

forecasts. Actual results could differ materially. to total risk-weighted assets.]

NON-GAAP FINANCIAL MEASURES:

In this document, we sometimes use information derived from consolidated financial data but not presented in our

financial statements prepared in accordance with U.S. generally accepted accounting principles (GAAP). Certain of

these data are considered “non-GAAP financial measures” under the U.S. Securities and Exchange Commission

rules. These non-GAAP financial measures supplement our GAAP disclosures and should not be considered an

alternative to the GAAP measure. The reasons we use these non-GAAP financial measures and the reconciliations

to their most directly comparable GAAP financial measures are posted to the investor relations section of our

website at www.ge.com. [We use non-GAAP financial measures including the following:

• Operating earnings and EPS, which is earnings from continuing operations excluding non-service-related pension

costs of our principal pension plans.

• GE Industrial operating & Verticals earnings and EPS, which is operating earnings of our industrial businesses and

the GE Capital businesses that we expect to retain.

• GE Industrial & Verticals revenues, which is revenue of our industrial businesses and the GE Capital businesses

that we expect to retain.

• Industrial segment organic revenue, which is the sum of revenue from all of our industrial segments less the

effects of acquisitions/dispositions and currency exchange.

• Industrial segment organic operating profit, which is the sum of segment profit from all of our industrial segments

less the effects of acquisitions/dispositions and currency exchange.

• Industrial cash flows from operating activities (Industrial CFOA), which is GE’s cash flow from operating activities

excluding dividends received from GE Capital.

• Capital ending net investment (ENI), excluding liquidity, which is a measure we use to measure the size of our

Capital segment.

• GE Capital Tier 1 Common ratio estimate is a ratio of equity

Node-Breaker Model in GE PSLF NERC Webinar December 6, 2016

© 2016. General Electric International, Inc. (GEII) This information is proprietary and confidential. Not to be copied, distributed, or reproduced without prior approval.

Background

December 6, 2016 Node-Breaker model in GE PSLF 3


Node-Breaker model in PSLF


• Developed in close collaboration with

• Western Electricity Coordinating Council (WECC)

• Peak Reliability (Peak RC)

• Bonneville Power Administration (BPA) and other WECC members

• PSLF supports

• node-breaker model

• bus-branch model

• hybrid model (bus-branch and node-breaker)




• Completely integrated into

• Power Flow package

• Dynamics package

• Geo magnetic disturbance package

• Contingency processor

• Remedial Action Schemes (RAS)

• Benchmarked with several actual disturbances

• Can be used for model validation, next day studies, NERC MOD 033


Node-Breaker Model in GE PSLF



Bus-branch vs Node-breaker model


• Based on node-breaker representation

• Switching devices and nodes are represented properly

• Snapshots saved every few minutes from EMS based upon actual system conditions

• EMS labels used are used as primary key to identify different power system assets

• Based on bus-branch representation

• Switching devices are not typically modeled and nodes are collapsed as buses

• Dozens of cases created annually by planners based upon forecasted conditions

• Bus identifiers are used as primary key to identify different power system assets

Planning Bus-branch model Operations Node-breaker model


Bus-branch vs Node-breaker model for the same system


Planning Bus-branch model Operations Node-breaker model


Breakers


Modelled explicity

Breaker types

• Disconnects

• Circuit Breakers

• Fuses

• Links

• Other Switching

devices


Nodes


• Modeled as regular bus

• Flag to indicate whether bus is a node or a planning bus

• PSLF internally figure out real node vs. buss based upon breaker connections




• Bus numbers are not typically used as unique identifiers in node-breaker model

• EMS labels used as unique identifiers

• Other objects seen in operations node-breaker case

• Balancing authority

• Substations


Balancing Authority


• Similar to Area, but represents actual BA

• BA footprint doesn’t need to be coincide with control areas or zones

• Data can be populated from EMS model

• Used for NERC BAL-003


Substations


• Models physical substation

• Typically represented by a bus or set of buses in the planning case

• Substation data is readily available in operations case and represented as a new record/object in node-breaker case

• Required for CIP-014-1, TPL-001-4


Importing EMS data into PSLF


• Some EMS which directly exports State Estimator model in GE PSLF (*.EPC) format

• GE E-Terrasource

• GE XA/21

• OSI Monarch

• PSLF can also directly import GE E-Terrasource HDB export in full topology (node-breaker) format


Demo of PSLF node-breaker model



Using EMS cases for model validation using GE PSLF



Traditional method of model validation using operations case



New method of model validation using operations case


B. Thomas, S Kincic, D. Davies, H. Zhang, J.J. Sanchez-Gasca, “A New Framework to Facilitate the Use of Node-Breaker Operations Model for Validation of Planning Dynamic Models in WECC”, PES GM July 2016, Boston


Efficiency Improvements



Some Results of Model Validation using WECC EMS Model in GE PSLF



Brake Insertion Test, Spring 2014 – Frequency Response



Generation Drop RAS, May 2014 – Voltage Response



Generation Drop RAS, May 2014 – MW Response



Brake Insertion Test, June 2015– Major WECC Path Response



Some other system events benchmarked using PSLF node-breaker model


• Jan 29, 2014 (BPA RAS)

• April 9, 2014 (Four Corners unit trip)

• Chief Jo brake test (April 24th 2014)

• May 16, 2014 (BPA RAS)

• May 26, 2014 (BPA RAS)

• October 18, 2014 (Colstrip unit 3 tripped)

• April 28, 2015, (loss of PDCI)

• May 28, 2015 (reclosing of Garrison Taft )

• June 17, 2015 (Chief Jo brake test)

• Sept 1st, 2015 loss of Navajo unit

• Sept 5th 2015 loss of two Colstrip units

• Sept 15th, 2015 loss of Navajo unit

NODE/BREAKER MODELING IN DSATOOLS SOFTWARE

Lei [email protected]

Powertech Labs Inc.

December 6, 2016

2

Introduction

• This presentation discusses the method used in Powertech’sDSAToolsTM software to handle power system models in node/breaker format

• This modeling method was initially designed for on-line dynamic security assessment

• There is a trend to extend such modeling capability for off-line planning studies

• So this has been made available in the off-line modules of DSATools

3

Background

• A set of models are required for power system analysis• Powerflow

• Stability

• Other

• These include the following data sets• Powerflow

• Dynamics

• Other (contingencies, quantities to be monitored, sequence network, special protection systems or SPS, etc.)

• Such models can be presented in one of two formats• Bus/branch

• Node/breaker

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Bus/branch vs node/breaker format

• Primarily for real-time applications in EMS

• For integrated and automated applications

• Data from real-time databases

• Primarily for planning (off-line) studies

• For stand-alone applications

• Data from flat files

Node/breaker formatBus/branch format

• These have been used successfully in their application domain for long time

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Salient nature of bus/branch format

• Nodes in a system connected by busbars, breakers (switches) are usually consolidated to form a bus• Compact model size

• Node/breaker configuration topology is lost

• Assumption is that tripping of one component would not cause another component to be tripped

• Critical breakers that must be kept in the model can be represented as zero impedance lines

• All components are referred to by the buses they are connected to

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Salient nature of node/breaker format

• Busbars, nodes, and breakers (switches) in substations are explicitly included in the system model• Physically based

• Full topology available

• Resulting model size may be very large

• Components are referred to by their names (ID)

• Most actions to be analyzed in studies are specified in the form of breaker operations• Contingency actions

• SPS actions

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Motivation for the migration

• Changes on technologies and standards• PMU-based applications

• On-line dynamic security assessment

• Regulatory requirements for reliability assessment: TPL, CIP, etc.

• Cascading outage analysis

• Data availability (CIM, etc.)

• Advancement in in computer technologies

• This makes it desirable to perform system studies using models in node/breaker format• NERC compliancy studies

• Model validation

• Operational or planning studies

• Analysis of incidents

There is a trend to migrate from bus/branch to node/breaker format

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Considerations for developing the solution

• Compatible, to a feasible degree, between the two formats• Case where node/breaker information may not be available for part

of the system

• Conversion from node/breaker to bus/branch (not vice verse)

• Maintaining reasonable model size• Perhaps not every breaker and switch need to be kept

• Efficiency and user-friendliness• A typical example is in contingency definition:

• If using entirely breaker operation, multiple breaker actions are required to trip a circuit

• This may not always be desirable

• Handling of the node/breaker model in computation engines

• User interface

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Powertech’s approach – powerflow

• A powerflow case is still defined in the conventional bus/branch format• Component equipment names are included in this data

• Extension to accommodate node/breaker data• Node/breaker data in XML format can be provided for a portion of

the system

• This is optional

• This approach is fully compatible with the bus/branch modeling approach• It is believed that it is also compatible with node/breaker formats

from other software vendors. Conversion utilities can be developed if required.

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Powertech’s approach – powerflow (cont’d)

• The node/breaker XML data contains two types of information:

• Definition of new components for the node/breaker modeling

• Station

• Busbar

• Node

• Connector (breaker or switch)

• Additional information for conventional components (load, generator, line, etc.) defined in the bus/branch format

• Equipment name (ID)

• Connectivity to nodes

• The node/breaker XML data can be automatically created in PSAT when such data is created using PSAT interface

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• An option is available to import CIM• Support CIM version 14, 15 and 16

• After the import, two data sets are created• Powerflow data in bus/branch format

• Node/breaker data in XML format

• The user can choose to use either bus/branch format or node/breaker format when dealing with the powerflow case

• The CIM import feature is available for both off-line and on-line analysis

• This allows flexible exchange and sharing of data among different applications

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• Common powerflow analysis features are extended to node/breaker models in PSAT• Table/graphic display and editing of data

• Powerflow solution and other solution options

• Various data checking and solution reporting options

• In terms of graphical display, a new type of graph (Station Diagram) can be created to show the node/breaker connectivity details

• The full model can be saved with the same concept• A full powerflow in bus/branch format

• Node/breaker data in XML format

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Node/breaker data examples

Definition of a station

Definition of a busbar

<BusBarSection>

<Name>BE-BB1</Name>

<SubstationName>Brussels</SubstationName>

<ID>1</ID>

<IncludeNodeName>PP_Br 15 38NodeBB3</IncludeNodeName>



</BusBarSection>

<Substation>


<Number>2</Number>

<Type>7</Type>

<KV>0.00</KV>

<Latitude>0.000000</Latitude>

<Longitude>0.000000</Longitude>

<GroundingR>0.00000</GroundingR>

</Substation>

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Definition of a node

Definition of a breaker

<Node>

<NodeName>PP_Br 15 38NodeBB1</NodeName>

<ID>22</ID>

<PreferBus>0</PreferBus>

<Bus>PP_Br 15 38</Bus>

<OldBus>PP_Br 15 38</OldBus>

</Node>

<BreakerSwitch>

<EquipmentName>BE-BRK5</EquipmentName>


<Status>Close</Status>

<NormalStatus>Close</NormalStatus>

<FromNodeName>PP_Br 28 11Node</FromNodeName>

<ToNodeName>PP_Br 10 11NodeBB3</ToNodeName>

<Type>BRK</Type>

<CKTID>3</CKTID>

<X>0.00000</X>

<Rating1>0.00</Rating1>



</BreakerSwitch>

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Information required for a generator in node/breaker format

Information required for a line in node/breaker format

<Generator>

<EquipmentName>NL-G2</EquipmentName>

<SubstationName>Amsterdam</SubstationName>

<NodeName>PP_Am 11 15NodeBB4</NodeName>

</Generator>

<ACLine>

<EquipmentName>BE-Brussels2 9-8</EquipmentName>

<FromSubstationName>Brussels</FromSubstationName>

<FromNodeName>PP_Br 17 22NodeBB2</FromNodeName>

<ToSubstationName>Anvers</ToSubstationName>

<ToNodeName>Anver 18 22NodeBB2</ToNodeName>

</ACLine>

Other parameters for generator, line, etc. are defined in the bus/branch data

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Node/breaker data editing interface examples

Data tables for node/breaker components

Details of the busbar data table

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Mixed station and single-line diagram

Generation plant and transmission substation. Details are defined in node/breaker format and can be viewed in Station diagrams

Data only in bus/branch format can be viewed with the conventional single-line diagram

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Station diagram

Full topological connectivity can be shown, with busbars, nodes, and connectors, for one station

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Powertech’s approach – stability analysis modules

• Equipment names are required for components that off-line studies have to deal with. Examples:• Node (or bus)

• Load

• Generator

• Transmission line

• Transformer

• Shunt

• Equipment names are unique for each component and independent of system conditions• All data required for stability analysis (such as dynamics) is defined

with equipment names

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Contingency definition for stability analysis

• Contingency definition is one of the areas to benefit from the node/breaker modeling• Detailed switching actins at the breaker level can be included in the

contingency definition

• Consistent with the actual sequence of actions occurring in field

• Easier to define particular type of contingencies, such as stuck breaker events

• This concept has been extended to the modeling of Remedial Action Schemes (RAS) or special protection systems (SPS)• Actions from RAS or SPS can be component-based or breaker-based

Contingency definition example – a stuck breaker event

A TSAT stuck breaker event script:

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Description Sample Stuck Breaker EventSimulation 10.0 SecondsStep Size 0.25 CyclesApply Stuck Breaker ;‘S1B2' ;'' ; At Time 0.5 SecondsOne Phase To Ground Fault On Line ;‘LINE-S1-S2#1' ;'' ; 0After 4 CyclesApply Normal Clearing At Near End ;' LINE-S1-S2#1 ' ;'' ; After 2 CyclesApply Normal Clearing At Far End ;' LINE-S1-S2#1 ' ;'' ; After 6 CyclesApply Delayed Clearing ;‘S1B2' ;'' ; Clear One Phase To Ground Fault On Line At Near EndClear One Phase To Ground Fault On Line At Far EndNomore

S1B1

S1B2

S1B3

S1B4

S1B5 S1B6

S2B2

S2B1

S2B3

LINE-S1-S2#1

LINE-S1-S2#2

TRAN-S1#1

TRAN-S1#2

GEN-S1#1

As shown, after TSAT executes this script, breakers S2B1, S2B2, S1B1, S1B3, S1B5, and S1B6 open. As a result, line LINE-S1-S2#1 and transformer TRAN-S1#1 are tripped.

Other contingency examples

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A

B

A B

C

When breaker 3 is open in powerflow case and line A is tripped during simulation, breakers 1 and 2 will be automatically opened. This effectively trips line B as well.

Line C is tapped on line A+B. When line A is to be tripped during simulation, all five breakers shown in the figure will open (determined by the automatic topology analysis in simulation engine). Thus lines B and C are also tripped.

1

2

3

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Applications

• The node/breaker modeling approach described here has been applied to on-line dynamic security assessment• In testing/production use at two major system operators in NERC

region

• Full node/breaker model is included in the real-time cases

• The largest case includes more than 20,000 nodes and 17,000 breakers/switches which are collapsed to cases with about 4,600 buses in computation engines

• A simpler modeling approach, in which partial node/breaker details are included, has been used in more than a dozen similar applications in NERC region• It is expected that most of these systems will be upgraded to the full

node/breaker model

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Performance

• The node/breaker modeling approach described here is fairly efficient in terms of computational speed• As been proved in on-line DSA application which has strict

performance requirements

• There has been no significant impact in terms of computation time, due to the use of node/breaker modeling

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Future tools / applications

• A separate tool is being developed at Powertech to create contingencies that are compliant to NERC TPL standard• All categories of contingencies will be covered, including stuck

breaker events, etc.

• Node/breaker data is critical to define some of the contingencies

• The plan is to possibly extend this tool for other NERC standards, such as CIP-14

• New features will also be added in short-circuit analysis, to take advantage of the node/breaker models

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Questions?

node-breaker modeling representation validation...node-breaker modeling representation . on december...

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