A Family of CIM EMS Exchange Standards based on CIM/XML ( ) - Static Network Model Exchange ( ) - Dynamic Model Exchange? - Schematic Layout Exchange ( ) - Solved State Exchange ( ) - EMS Static Model Update (proposed) - - Contingency Definition? - … Jay Britton

33 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.

44 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.

55 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.

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

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

88 CIM Exchange (full, partial, incremental update) The initial CIM model exchange ( ) standard focused only on transfer of complete models: A Internal Model A’s model of B b a Proprietary / 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

99 A More Desirable Process 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 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

11 Typical North American Operations Boundary

12 Typical ENTSO-E Operations Boundary

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.

14 Consolidating Planning with Operations  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 The Naming Problem

16 Evolving Support for Analytical Processes  The original 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’  ENTSO-E Day Ahead Congestion Analysis  EPRI ‘CIM for Dynamics’  Recent IEC WG13 Accomplishments  now supports planning models in addition to operations.  Draft defines solved power system state exchange. Operations and planning share the same standard. ENTSO-E DACF supported.  Draft defines display layout exchange.  Update of includes header specifications.  Current WG13 Agenda  Unify distribution and transmission network modeling.  Object registry specification

17 Current Modularity  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.  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.  Display Layouts The position of objects within a schematic or geographic presentation.

Profiles

19 Dependency Relationships to be Expressed in Headers

20 DACF Process

21 Combining profiles into a complete solution description.

22 Partitioning into Files by TSO

23 Complete View of Partitioning Into Files

24 ENTSO-E Interconnection Solution

25 Partitioning of EMS Static Model

26 Partitioning of EMS Solved Cases

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 Display Layout UML Proposal

29 ENTSO-E Case – Display Layout Exchange