1. Model Specification Requirements MSRATF Meeting – Mar 11, 2013 Stephanie Lu, MVWG Chair Seattle City Light

2. WECC Dynamic Modeling Procedure 1. All dynamic models contained in the Master Dynamic Data File (*.dyd) shall be those approved by MVWG. 2. MVWG is the entity responsible for keeping the Approved Dynamic Model Library up to date approving any changes or additions working with the appropriate stakeholders to ensure that adequate and compatible models are available for use in large-scale simulation platforms supported by WECC

3. WECC Dynamic Modeling Procedure (cont.) 3. If a generator, load or other dynamic control device cannot be appropriately represented with a model listed in the Approved Dynamic Model Library, the interested party is expected to consult with MVWG for further guidance. The following guidelines are applicable: Specific models that are not in the Approved Dynamic Model Library may be added to the Master Data File with MVWG approval. If MVWG determines that a new model needs to be added to the WECC Approved Model Library, the owners of the equipment and equipment vendors, as appropriate, are expected to work with MVWG to develop a suitable model and/or provide complete model documentation. This procedure is not intended to stifle development of new models, or discourage the use of models considered more appropriate for specific studies of local interest.

4. Examples of Model Development and Approval Process For recently approved models and/or model specifications e.g. SVS, Wind and PV Models: Develop model specifications (TF) Test beta model (TF) Approve model specifications (TF, MVWG, TSS) Test and implement model (TF) Provide guideline documentation for implementation (TF) Approve in Approved Dynamic Models List (MVWG, TSS) Update DPM, as needed, to include models (SRWG) Include in rep logs as it makes sense (SRWG) and/or in data checking tools (MVWG PPMDTF)

5. Steps for Model Development and Approval – Proposal for MSRATF Initiated Models For Relay Models: Develop model specifications (MSRATF Relay Subgroup) Test beta model (MSRATF Relay Subgroup) Approve model specifications (MSRATF, MVWG, and TSS) Test and implement model (MSRATF Relay Subgroup) Provide tutorial or guideline type document for implementation (MSRATF Relay Subgroup) Approve model to be in Approved Dynamic Models List (MVWG) Update DPM, as needed, to include models (SRWG) Include in rep logs as it makes sense (SRWG) and/or in data checking tools (MVWG PPMDTF) For RAS models, above process may also be used If process needs to be expeditious, the option of email voting may be considered.

6. Purpose of Model Specifications To provide consistent model specifications, requirements, and naming conventions for vendors to implement in their programs To facilitate ability to convert models between programs (since all vendors are implementing the model using the same specifications) A document for a common understanding of the model and its purpose (for vendors and WECC members) To develop an appropriate number of approved models for use in large-scale simulation (include all the models needed to meet WECC modeling needs in the least number of models possible)

7. Model Specifications Content Background / Introductions Purpose / Application Description of Model Function Model Requirements for Software Implementation Assumptions and Prerequisites (e.g. powerflow model) Block Diagram(s) List of Input Parameters, Internal Variables, and Output Channels Parameter Name, Description, Units, and Typical Parameter Values and Range in Values Equations for other functional logic (as necessary) Simulation / Validation Examples Conclusions / Summary References (as applicable)

8. Model Specifications Example Example Demo: WECC Solar PV Dynamic Model Specification WECC Solar PV Dynamic Model Specification Examples can be found on the WECC website: MVWG / Documents / MVWG Approved Documents MVWG / Documents / MVWG Approved Documents WECC Solar PV Dynamic Model Specification - September 2012 WECC Static Var System Modeling Aug 2011 WECC Type 3 Wind Turbine Generator Model - Phase II 012313 WECC Type 4 Wind Turbine Generator Model - Phase II 012313 Report_rev3 wt1 wt2