A Family of CIM EMS Exchange Standards based on CIM/XML (61970-552)

- Static Network Model Exchange (61970-452)- Dynamic Model Exchange?

- Schematic Layout Exchange (61970-453)- Solved State Exchange (61970-456)

- EMS Static Model Update (proposed)- - Contingency Definition?

- …

Jay Britton

jay.britton@areva-td.com

3 3

The Basic Model Exchange Business Problem

The members of an interconnection share a mutual necessity to achieve: Accurate assessment of grid reliability.

Appropriate, timely response to insecure conditions.

A pre-requisite to the above are: Accurate, up-to-date network models.

Consistent network models (at each responsible site).

In an interconnection, this requires: Exchange of models.

Exchange of solved analytical results.

2008 NERC Real-Time Best Practices Report: “Although defining the elements represented in internal network models is relatively

straightforward, the task force finds that defining the elements to be represented in external models is much more complex.”

“Issue #5: External Modeling and Data Exchange Practices Should be Improved by Explicit Reference to the Definition of the Wide-Area-View Boundary. A consistent, uniform set of modeling and data exchange practices, procedures, and standards are needed to support creation and maintenance of accurate external models…”

These requirements apply in operations and planning contexts.

4 4

There is high-level consensus about the right approach.

Basic Modeling: Each TSO is the authority for data about its own territory.

Each TSO exports its internal model to its neighbors and/or regional authority, and keeps it up to date.

Regional authorities assemble internal regional models from member TSO internal models.

All parties assemble external models from the internal models of other sites.

Analysis: Responsibility is usually distributed among cooperating sites.

Solution exchange is required, depending on the problem. Exchanged solutions should be based on consistent underlying

models.

These goals apply to both operations and planning. Operations focus is on as-built and near future changes.

If operations and planning share the same as-built base model, then the planning focus is on exchange of plans.

5 5

Contributing Use Cases

Exchange of network models. EMS A and B are neighbors in an interconnection and therefore each needs

to represent the other as part of its external model.

Requires exchange of internal models.

Scope is limited to network data and measurement placements.

Exchange of schematics with models is desirable.

Common Modeling Source between planning and operations. One modeling application for the enterprise.

An EMS requires a model that covers any point in time.

Other targets require data for a specific “case”.

Exchange of solved cases. Several variations… Real-time exchange among different applications.

Real-time cases to study or planning.

Exchange of study or planning cases between different tools.

Import of study cases to EMS.

ENTSO-E DACF. Study cases are generated for the next day by each TSO representing the

expected state of their internal network.

6 6

A Generic Model Exchange Business Process(ENTSO-E, ERCOT, WECC, …)

PRIMARY Interconnection

Model

Derived Model

TSO 1 External Model

Assembly of full primary model

Creation of derived target models

TSO 1 EMS

TSO 2 EMS

TSO n EMS

Interconnection EMS

TSO 1 Internal Model

TSO 2External Model

TSO 2 Internal Model

TSO n External Model

TSO n Internal Model

Interconnection Planning

Derived Model

TSO 1 Plans

TSO 2 Plans

TSO n Plans

7 7

Preview – We are working toward defining model partitioning into non-overlapping XML submodels that satisfy all of the use

cases.

Global Model Objects

Regional EMS Static Model

Bndry

Regional EMS Static Model

Regional EMS Static Model

Bndry

Partition by Object Instance using Model Authority Sets

Par

titio

n by

CIM

Sch

ema

Ele

men

ts

Common Objects

Display Layout

Equip Model

Display Layout

Equip Model

Display Layout

Equip Model

Solution

Measurements

Meas

State Variables

Topology

Measurements

Meas

Measurements

Meas

8 8

CIM Exchange(full, partial, incremental update)

The initial CIM model exchange (61970-452) standard focused only on transfer of complete models:

A Internal Model

A’s model of B

baProprietary / Home grown

Extract / Merge Tools

Proprietary / Home grown

Extract / Merge Tools

CIM import / export

System A Local Vendor

Model

System A Import Model

B’s Model of A

B Internal Model

System B Local Vendor

Model

System B Import Model

CIM import / export

System A EMS System B EMS

9 9

A More Desirable Process

CIM ModelerFullInterconnectionModel

CIM ModelerFullInterconnectionModel

EMS at Site BEMS at Site A

System A Source

System B Import

boundary

System B Source

System A Import

boundary

My A Region(reduced & renamed)

My B Region(reduced & renamed)

CIM Translator A

EMS AProprietary Model Format

CIM Translator B

EMS BProprietary Model Format

CIM/XMLModel Exchange

Interface

a b

Site A makes a change:

1. A changes its ModelAuthoritySet using its CIM modeller.

2. A imports the change into its EMS.

3. A exports the change to B.

4. B receives the change (full or incremental), updating A’s ModelAuthoritySet within its CIM modeller.

5. B renames any new elements and repeats any reduction of A’s ModelAuthoritySet.

6. B imports the new model into its EMS.

10 10

Merge/Extract with Model Authority Sets

Each object is in one and only one set.

Simple labeling technique for assigning responsibility.

Associations connect some objects that are in different sets.

Currently directional from n to 1 (“foreign key” convention) – under discussion.

Regional Sets: No associations with other

regional sets.

External associations to boundary sets only.

Boundary Sets: External associations from

regional sets.

External associations with other boundary sets.

A regional set may be referentially validated independent of other regional sets.

Modeling processes can proceed independently in each region.

Goal: Maximize independence.

Design boundary sets to achieve:

Minimum data Infrequent change

Model Authority SetB

Model Authority SetA

Model Authority SetC

A-B boundaryMAS

B-C

bou

ndar

yM

AS

A-C

bou

ndar

yM

AS

11 11

Typical North American Operations Boundary

Model Authority Set C

A-C Boundary

Set

CN

Model Authority SetA

TT LS

A Region Transmission Line

C Region Substation

m

Tie Line Metering Point

T

T

CB

CN

T

T

CB

T

T

CB

T

BB

ST

GEO=’C’

LN

GEO=’A’

12 12

Typical ENTSO-E Operations Boundary

Model Authority Set CA-C Boundary

Set

CN

Model Authority SetA

T

T

CB

CN

Tie Line

C Region Substation

m

T

T

CB

T

T

CB

Tie Line Mid-point

A Region Substation

CN

T

BB

TLST

T

T

CB

CN

T

T

CB

T

T

CB

T

BB

TLSTCN

STST

GEO=’C’GEO=’A’

LN=’X-Y’

ST=’X’ ST=’Y’

13 13

Hierarchical Process Definition for an Interconnection

Bottom level.

No significant differences.

Export changes as the model authority.

Import externals from the full interconnection model.

Upper level:

Manages boundary sets.

Creates the full interconnection model.

Model quality evaluation.

Study state estimation.

Derives operational model in the same manner as lower levels.

Different reduction criteria.

Design extends to any number of hierarchical levels.

CIM Modeler

CIM ModelerFullInterconnectionModel

CIM ModelerFullInterconnectionModel

EMS at Site BEMS at Site A

System A Source

System B Import

boundary

System B Source

System A Import

boundary

My A Region(reduced & renamed)

My B Region(reduced & renamed)

CIM Translator A

EMS AProprietary Model Format

CIM Translator B

EMS BProprietary Model Format

a b

FullInterconnectionModel

System A Import

System B Import

boundary x

Upper Level Reliability Model

EMS at Upper Level Authority

CIM Translator

EMS Upper LevelProprietary Model Format

14 14

Consolidating Planning with Operations

CIM Modeler

CIM ModelerFullInterconnectionModel

CIM ModelerFullInterconnectionModel

EMS at Site BEMS at Site A

System A Source

System B Import

boundary

System B Source

System A Import

boundary

My A Region(reduced & renamed)

My B Region(reduced & renamed)

CIM Translator A

EMS AProprietary Model Format

CIM Translator B

EMS BProprietary Model Format

a b

FullInterconnectionModel

System A Import

System B Import

boundary x

Upper Level Reliability Model

EMS at Upper Level Authority

CIM Translator

EMS Upper LevelProprietary Model Format

Interconnection Planning Model

Planning System

CIM Translator

Planning SystemProprietary Model Format

Full interconnection model is the common source for all models.

Interconnection planning shown on diagram.

No procedural difference required to support analytical functions running at any level for any purpose.

Planning adds other requirements.

New information modeling in CIM.

Accommodate bus-oriented apps.

Add short circuit, dynamics, etc.

Incremental model standard expands to model plans.

CIM modeling applications need to have a temporal axis.

2007 EPRI “CIM for Planning” project.

Goal is eliminate duplication of modeling.

15 15

The Naming Problem

PRIMARY Interconnection

Model

Interconnection Model

TO 1 External Model

Assembly of full primary model

Creation of derived target models

TO 1

TO 2

TO n

Regional Authority

TO 1 Internal Model

TO 2External Model

TO 2 Internal Model

TO n External Model

TO n Internal Model

Interconnection Object Registry

Name translation point

Primary registration point

16 16

Evolving Support for Analytical Processes

The original 61970-452 standard exchanged EMS models. Did not deal with planning (‘bus-branch’ models).

Did not support power flow solution exchange (or any other type of analytical result).

Several recent efforts defined other needed support. 2007 EPRI ‘CIM for Planning’

2008-2010 ENTSO-E Day Ahead Congestion Analysis

2008-2009 EPRI ‘CIM for Dynamics’

Recent IEC WG13 Accomplishments 61970-452 now supports planning models in addition to operations.

Draft 61970-456 defines solved power system state exchange. Operations and planning share the same standard. ENTSO-E DACF supported.

Draft 61970-454 defines display layout exchange.

Update of 61970-552 includes header specifications.

Current WG13 Agenda Unify distribution and transmission network modeling.

Object registry specification 61970-453.

17 17

Current Modularity

61970-452 Static Model. Equipment Profile.

Identifies equipment and describes basic characteristics. Describes electrical connectivity that would be input to topology processing. (Optional

for planning.) Describes input to functions that derive parameters for a specific point in time. (Optional

for planning.)

Dynamics Profile. Describes dynamic characteristics.

61970-456 Solved Power System State Topology Profile.

The result of topology processing. i.e. Description of how equipment connects into buses and how buses makeup connected systems.

Analogs Profile. The set of SCADA values for analog measurements for a particular point in time.

Status Profile. The state of switches – input to topology processing.

State Variables Profile. This is the set of state variables used in the mathematical formulation that the algorithms

work with.

- Used to represent starting conditions or ending conditions of analysis.

61970-454 Display Layouts The position of objects within a schematic or geographic presentation.

18 18

61970 Profiles

19 19

Dependency Relationships to be

Expressed in Headers

Equipment Model

TopologyState

VariablesCommon Objects

C1 S1T1E1

E1.1

T1.1

T1.2

T1.3

S10

S9

S8

S7

S6

S5

S4

S3

S2

S12

S11

20 20

DACF Process

text

text

text

TSO

X-NodeList

TSO

TSO TSO TSO

TSO My TSO

My TSO

Export my TSO Model to UCTE Server

Import neighbor TSOs from UCTE Server

Merge

Impo

rt a

ll T

SO

mod

els

to

UC

TE

Ser

ver

TSO

TSO

TSO

UCTE Model Server

My TSO’s Cases for Export

My TSO

Model Maintenance

text

TSO

TSO TSO TSO

TSO My TSO

My TSO’s Congestion Analysis Model

text

TSO

TSO TSO TSO

TSO My TSO

Market

Outcomes

Next Day’s Case Development

21 21

Combining profiles into a complete

solution description.

State Variables

TSO Topology

TSO Equipment Model

ACLineSegment

ControlArea

CurrentLimit

CurveData

EnergyConsumer

FossilFuel

GeneratingUnit

GeographicalRegion

HydroGeneratingUnit

HydroPump

MutualCoupling

NuclearGeneratingUnit

OperationalLimitSet

PhaseTapChanger

PowerTransformer

RatioTapChanger

ReactiveCapabilityCurve

RegulatingControl

SeriesCompensator

ShuntCompensator

SubGeographicalRegion

Substation

SvPowerFlow SvShuntCompensatorSections SvTapStepSvVoltage

Switch

SynchronousMachine

Terminal

Terminal (about)

ThermalGeneratingUnit

TieFlow

TopologicalIsland

TopologicalNode

TransformerWinding

VoltageLevel

VoltageLimit

WindGeneratingUnit

UCTE Common Objects BaseVoltage OperationalLimitType

ControlAreaGeneratingUnit

LoadResponseCharacteristic

22 22

Partitioning into Files by TSO

TSO Equipment Model

TSO Topology

TSO Equipment Model

State Variables

X-nodes

TN

TSO Topology

TN

Tie Line

B Region Substation

m

T TLS

T TLS

Tie Line Mid-point

A Region Substation

TLST

TN

TLST

T TLS

T TLS

State Variables FL

FLFL FLV VFL

FL

FL FL FL

FL

FL

TaTa

EG T

Ta

Ta

Ta

EGT

Ta

Ta

FL

FL

FL

Ta

Ta

Ta Ta

Ta

Ta

Ta

23 23

Complete View of Partitioning Into Files

GlobalMA

Regional Solved Case

Equipment Model

Topology

State Variables

Xnode

RegionalSolved Case

Equipment Model

Topology

State Variables

RegionalSolved Case

Equipment Model

Topology

State Variables

Xnode

Partition by Object Instance using Model Authority SetsP

artit

ion

by

CIM

Sch

em

a E

lem

en

ts

Common Objects

24 24

ENTSO-E Interconnection Solution

GlobalMA

Regional Model

Equipment Model

Topology

Xnode

Regional Model

Equipment Model

Topology

Regional Model

Equipment Model

Topology

Xnode

Partition by Object Instance using Model Authority SetsP

artit

ion

by C

IM S

chem

a E

lem

ents

Common Objects

Global SolutionState

Variables

25 25

Partitioning of EMS Static Model

Global Model Objects

Regional EMS Static Model

Bndry

Regional EMS Static Model

Regional EMS Static Model

Bndry

Partition by Object Instance using Model Authority Sets

Par

titio

n by

CIM

Sch

ema

Ele

men

ts

Common Objects

Display Layout

Equip Model

Display Layout

Equip Model

Display Layout

Equip Model

26 26

Partitioning of EMS Solved Cases

Global Model Objects

Regional EMS Static Model

Bndry

Regional EMS Static Model

Regional EMS Static Model

Bndry

Partition by Object Instance using Model Authority Sets

Par

titio

n by

CIM

Sch

ema

Ele

men

ts

Common Objects

Display Layout

Equip Model

Display Layout

Equip Model

Display Layout

Equip Model

Solution

Measurements

Meas

State Variables

Topology

Measurements

Meas

Measurements

Meas

27 27

61970-453 Display Layout Exchange

Purpose: To exchange schematic display layouts accompanying model or solution exchanges.

Corresponds to the part of display maintenance work that normally goes with model maintenance.

Defines graphic objects used in the sender’s displays: Usually linked to a model object, but can also be background.

One or more location coordinates. (Optional glue points.)

Graphic style reference.

Does not define Interpretation of graphic style references.

Usage Sender describes diagram.

Senders disclose the way their system uses graphic styles. Object placements describe sender’s diagram as is.

Receiver must decide how to render the diagram in its system. Create interpretation of sender’s styles. Receivers are not expected to duplicate functionality. Receivers may break apart complex styles or combine simpler styles.

Receiver provides the graphic style interpretation models for their display management software.

Result: Layouts and names of things should be familiar.

Exact replication graphically is likely only when sender and receiver applications are the same.

Exact replication functionally is likely only when sender and receiver applications are the same.

28 28

Display Layout UML Proposal

29 29

ENTSO-E Case – Display Layout Exchange

Display Bndry

TSO Equipment Model

TSO Topology

TSO Equipment Model

Display Layout

X-nodes

TN

TSO Topology

TN

Tie Line

B Region Substation

m

T TLS

T TLS

Tie Line Mid-point

A Region Substation

TLST

TN

TLST

T TLS

T TLS

Display Layout DO

DODO DODO DO DO

TaTa

EC T

Ta

Ta

Ta

ECT

Ta

Ta

DO

DO

Ta

Ta

Ta Ta

Ta

Ta

Ta