MVWG Report to TSS August 2011

1. MVWG Report to TSSAugust 2011 Stephanie Lu Puget Sound Energy

2. Presentation Overview • Charter • Priorities and Work Plan • SVC Modeling • System Model Validation • Load Modeling • Renewable Generation Modeling • Synchronous Generation Modeling • HVDC Modeling • Modeling Workshop

3. MVWG Charter • MVWG reviewed the charter at the July 2011 meeting • Only one change is proposed – to change the review periodicity from annual to biennial • Document:M&VWGCharter2010April29_rev date 2011July15.docx • Motion: Approve the recommended change to the TSS and supporting work group charters, changing the review periodicity from annual to biennial, or as needed.

4. Priorities and Work Plan • Created in December 2010 Updated in July 2011 • Priorities: • Load Model Deployment • System Model Validation • Power Plant Modeling • Renewable Generation Models • SVC and HVDC Modeling Document: 2011JulyMVWGPriorities2011July21.docx

5. Priorities – Load Modeling • Complete the report on WECC Composite Load Model • Support ongoing load composition research, such as for air conditioner stalling • Develop a tool that detects events of Fault Induced Delayed Voltage Recovery using synchro-phasor and DFR data • Develop a tool to estimate load composition data • Perform model validation and system impact studies • Support Reliability Subcommittee efforts to understand the implications of criteria and standards • Support TSS efforts to implement the new models during base case development • Provide composite load model data files for base cases starting with the 2012 study program

6. Priorities – System Model Validation • Create cases to represent disturbances, using data available from the west wide system (WSM) cases. • Work with WECC RC to improve WSM cases. While the network topology representation is accurate, generation and load representation are significantly deficient. • M&VWG issued an RFP, evaluated proposals, and is working to contract with a vendor to provide tools and translation tables to link dynamic data to WECC power flow base cases. • System model validation is one of the deliverables under the Western Interconnection Synchro-phasor Program (WISP). M&VWG intends to perform as much as three model validation studies in CY 2012 to support the WISP efforts. • Participate in efforts by the NERC Model Validation Task Force to define power flow and dynamic system model validation methods.

7. Priorities – Power Plant Modeling • Implement a task force to review power plant data in the MDF • Verify power plant models • Conduct workshops on MOD-025, 26 and 27, and PRC-024 NERC Standards following their approval. • Deploy Generator Model Validation Tools at WECC offices and interested utilities for power plant model verification using synchro-phasor data. • Improve Synchronous Machine Models • As approved by TSS, WECC Staff translated gensal model data to gentpj model to better represent saturation effects and posted the revised master dynamics data file. There are 17 gensal models that need resolution. Translate all “gensal” models to “gentpj” models in MDF by November 2012.

8. Priorities – Power Plant Modeling (cont.) • Improve Excitation Models • Review whether 20 approved excitation models is appropriate, and whether the models can be reduced to a simpler set of static and rotating excitation models. • A 2011 contract with John Undrill will provide a tool to translate exciter data in WECC databases from old exciter models to similar new exciter models that will support over-excitation limiters. • Advance modeling of Over-Excitation Limiters (OEL), Under-Excitation Limiters (UELs), and generator protection models. • Review and Develop Turbine Controls • Review turbine-governor models. No such review was done since 2002. There are signs that the modeled frequency response is again on the optimistic side. • Conversion to Kaplan models must be completed for generating units in lower-, mid-Columbia, and lower Snake rivers.

9. Priorities – Renewable Generation Models • Obtain additional default data for various types of wind generators. • Complete Phase 2 of the WECC wind modeling effort to develop improved models (especially for Type 3 wind generators) that better represent various manufacturers’ wind generators. • Explore feasibility of dynamic model validation at the wind plant level; this will require installation of monitoring equipment at the interconnection points. • Develop methods and power flow/dynamic models for representing solar photovoltaic installations.

10. Priorities – SVC and HVDC Modeling • Approval was obtained for the SVSMO1 model. • Obtain approval for the SVSMO2 and SVSMO3 models. Validation cases have been run and a report generated. • A High Voltage DC modeling Task Force (HVDCTF) has been formed and there was a kick-off meeting at the July 2011 M&VWG meeting.

11. Priorities and Work Plan • Motion: Approve and support the “M&VWG Priorities and Work Plan” as stated.

12. SVC Modeling

13. SVC Models • SVSMO1 – SVC model with TSC/TCR is implemented in PSLF and PSS®E – approved • SVSMO2 – SVC model with TSC/TSR • SVSMO3 – STATCOM model Presentation: SVC_Approval_JKPPSL_081911 .pdf Report: GenericStaticVarSystemModelsforWECC.pdf • Motion: Approve SVSMO2 and SVSMO3 models and add to the approved model list. Approve the SVS Model report titled ‘Generic Static Var System Models for the Western Electricity Coordinating Council’.

14. System Model Validation

15. System Model Validation Studies System model validation is a priority of MVWG System model validation is a deliverable under the Western Interconnection Synchro-phasor Program Goal: Start conducting system model validation studies in 2012 System model validation is part of the NERC Model Validation Task Force efforts Major impediment: Validation base case development Solution: Automate the process of base case development Leverage West-wide System Model (WSM)

16. System Model Validation Studies WECC Powerflow Case: Bus-branch Bus number, ID WSM Powerflow Case: Node-breaker-element Element Code 2 WECC Dynamic Database: Bus number, ID WSM Dynamic Database: Element code, node 1

17. System Model Validation Studies • Option 1: • Convert WECC dynamic data base to “element code” definition consistent with WSM (one time effort) • Validation studies are done using WSM powerflow case and the new dynamic data file • Option 2: • Map generation, loads and equipment status from WSM to WECC powerflow case • Validation studies are done using WECC powerflow case and existing dynamic database

18. System Model Validation Studies MVWG prepared RFP: Procurement team identified the preferred proposal and created a “short list”. WECC is working on the contract with the top proposal. RFP will focus on Option 1. MVWG resources will develop Option 2 as the short term solution.

19. System Model Validation Statement of Work • See Statement of Work for more information • Develop and deploy analytic tools for system model validation • Apply tools for power plant model calibration, composite load model calibration, sub-system model calibration, small signal model validation, and model validation using large disturbance data • Presentation: 2011-08 TSS - Model Validation in WECC.ppt • Document: WECC MVWG 2011 - SOW System Model Validation - 2011-08-16DGD.doc

20. Load Modeling

21. Composite Load Model Data • Presentation: 2011-08 TSS - WECC Compoite Load Model.ppt • Implementation Plan: Composite Load Model Implementation Plan 8-25-11.doc • Motion: Approve the Implementation Plan for the Phase 1 Composite Load Model.

22. Wind Generation Modeling

23. Status of Wind Modeling Effort PSLF/17 PSSE/32 • Version 1 of wind generic models implemented as library models in PSSE/PSLF & other platforms • Current focus is on • Refinement of models • Default data sets • Model validation

24. Phase 2 of wind model development – Model structure improvements • Type 1 and 2 improvements include: • Redesign aero/pitch model to better represent pitch strategy during low voltage conditions • Use LVRT flag to bypass rotor resistance control if LVRT situation occurs • Type 3 improvements to develop a non-GE specific model include: • Add option to bypass local volt/var controls • Review representation of the response during low voltage performance • Possibly add defensive pitch strategy similar to Type 1 and 2 • Add frequency droop for high frequency conditions • Type 4 improvements include: • Add option to bypass local volt/var controls • Add representation of mechanical side (shaft model) and option for direct torque control (current model is power control) • Add frequency droop for high frequency conditions • The specifications will be finalized at the next MVWG meeting

25. Wind Modeling - Implementation Plan • July/11 – REMTF memo requesting industry input • September/11 – Manufacturers reply • November/11 – MVWG to finalize specs for Phase 2 • January/12 – Phase 2 model development complete • March/12 – MVWG Approval • April/12 – TSS approval & transition plan • Possibly allow 6 to 12 month grace period to provide data • May/12 – Additional model testing

26. Real Example of MVAR Flows

27. Powerflow Modeling (Lesson Learned) Optimistic assessment of reactive requirements Wrong 230-kV 34.5-kV W Internal PF caps and external caps impacted by voltage squared (V^2/X) Right 230-kV 34.5-kV 0.6-kV W Collector system equivalent must include shunts to properly model for voltage stability studies

28. PV Generation Modeling

29. Large PV Power Plant Modeling • Current versions of PSLF and PSS®E have models that can be used for representation of large PV generation • PSLF Version 18 includes a WECC generic version of a PV system model, PV1, which has additional adjustable options to cover a wider range of inverter types. • PV1 model consists of two modules - PV1E and PV1G. It is a full featured model based on the WECC Type 4 wind generation model. • Refinements to the models are in progress. • Add active power control (up-ramp rate limit and high frequency droop) • Add voltage dip logic function • Add option to bypass local volt/var control • Consistent with the WECC PV Modeling Guide, the feeder or collector system equivalent should be included in the power flow model for large PV plants.

30. Distributed PV Modeling • Distributed PV modeling can be separated into: • large commercial (usually warehouse rooftop) installation • residential rooftop panels • PVD1 is a more basic model than PV1 and is intended to represent large distribution-connected PV that are represented in power flow as stand-alone generators. • Large commercial installations are modeled explicitly in powerflow base case. An EPCL has been developed by Dmitry Kosterev to add the commercial PV generation in powerflow cases. • A similar version of PVD1 will eventually be made part of the WECC Composite load dynamic model to residential or smaller-scale distributed PV that is load-netted in power flow. Specifications are not yet complete, as further discussion is needed.

31. PV Modeling – Path Forward Initial model specification Model specification document Model prototyping, testing Implementation in PSSE/PSLF/PW, other Validation and parameter sets PV Dynamic Modeling Guide Council approval Deployment/dissemination in WECC Model improvement/refinement cycle

32. Synchronous Generation

33. Synchronous Generator, Excitation and Turbine Control Models GENTPJ model – approved by TSS in January 2011 More accurate representation of over-excitation condition, particularly for salient pole machines Power Plant Model Data Task Force created – first meeting November 2011 Excitation model conversion to IEEE models RFP (2011) OEL, UEL and generator protection models (2011-13) Kaplan hydro turbine models (2011-13) Power Plant Model Validation

34. Update to gentpj model • Gensal models have been converted to gentpj in the MDF, with 17 exceptions that need additional investigation. • A note has been placed in the MDF zip file to document this change. • How to determine Kis factor for gentpj model: • If the V curve is not available, set Kis equal to zero. • If the V curve (no load curve and full load curve) is available, tune the Kis factor after the other parameters have been determined by matching the actual V curve and the model output. • An addendum to the baseline testing document to record the V curve data and a guideline on how to fit the curve using the Kis factor will be proposed at the next MVWG meeting in November.

35. Power Plant Model Data Task Force (PPMDTF) • The current process for generating unit model validation is described in the WECC Generator Unit Model Validation Policy. To summarize, • GO performs generator testing, validates generator model data and sends data/report to TP, • TP reviews and sends data/report to WECC, • WECC reviews (performs no disturbance test, etc.) and approves the generator testing and model validation reports, updates the Master Dynamics File (MDF), and issues certifications. • Gap in the process - TP does not review or does not have the expertise to adequately review the data and catch errors. There is currently only one WECC staff person who typically reviews and approves the changes. • PPMDTF will be an additional group that will help review and validate the data and assist the GO and TP to follow the Policy.

36. Power Plant Model Data Task Force - Purpose • Maintain accurate models of generators and associated controls for realistic simulations of the electric power system of the western interconnection. Minimize the number of errors in the generator model data in the Master Dynamics File (MDF). • Assist GOs and TPs to follow the WECC Generator Unit Model Validation Policy as per NERC Standard MOD-012-0, R1 and R2. • Assist GOs to follow applicable NERC Standards: • MOD-25 - verification of generator reactive capabilities • MOD-26 - verification of generator excitation system models • MOD-27 - verification of generator turbine control models • Provide education and expertise in the review of the model data and performing simulation verification.

37. Power Plant Model Data Task Force – Scope of Work • Coordinate review and validation of generator test results, and their proposed models and parameters with GOs and TPs. • Provide and develop the expertise in the review of additions and changes to power plant model data. • Perform a more in depth review, including additional simulation verification studies. • Review existing generator model data in MDF and create a dynamics data error list to address errors. • Provide an opportunity for training members of the Task Force by jointly reviewing, testing, and discussing power plant model data for accuracy. Develop technical expertise within the membership. • Develop additional tools for data checking.

38. Power Plant Model Data Task Force – Kick-off Meeting • 1st Meeting - Nov 2011 in conjunction with MVWG meeting • Proposed Agenda: • Review purpose/scope of work, develop a task force charter • Review the Generator Unit Model Validation Policy and discuss if any updates are helpful • Review recently submitted power plant models • Review existing power plant models and start a process to create a Dynamics Data Error List • Intended participants: • Experts and those interested in becoming experts in power plant testing and modeling. • Transmission Planners, Generator Owners, and others that submit and/or review modeling data. • Members that perform simulations that use the power plant models (includes both operations and planning).

39. Exciter Conversion • MVWG issued RFP to convert legacy excitation models to IEEE-approved excitation models • IEEE models are available in PSLF and PSS®E • IEEE models are identical to the legacy models with the exception that IEEE models have interface points for OELs and UELs • OEL and UEL modeling is essential for FIDVR risk analysis • Contract awarded to John Undril • Update provided at July MVWG meeting • Independent model translation program created with the ability to convert any model to any other model • Some models do not have a one-to-one equivalent, work is in progress • To be completed by November MVWG meeting • Deliverables include conversion map, rule file, manual, executable mcon program, mcon program source code, model validation report, epcl code for validation of individual model conversion

40. Power Plant Model Validation Power Plant Model Validation is one of the deliverable under WISP Power Plant Model Validation application is developed using PSLF play-in function Version 1A is available on the WECC website and was presented at the June Modeling Workshop An application is being developed for checking the “reasonableness” of the power plant response: Compare the actual response to “best practices”

41. Power Plant Model Validation Disturbance play-in function in GE PSLF • Inject PMU recordings of: • POI bus voltage • POI bus frequency Compare actual and simulated power plant MWs and MVARs Rest of WECC ~ Power Plant Developed under BPA Technology Innovation program

42. Power Plant Model Validation • Successful model validation for 550 MW combined cycle plant Voltage and frequency are inputs Active and reactive power are “measures of success” Blue line = actual recording Red line = model

43. Power Plant Model Validation • What a bad model looks like (800 MW steam-turbine unit) Voltage and frequency are inputs Active and reactive power are “measures of success” Blue line = actual recording Red line = model

44. Resources • NASPI Planning and Implementation Task team: • www.naspi.org • Power plant disturbance monitoring document • Technical session at the upcoming NASPI meeting on June 8-9 in Toronto, ON • Presentation at NERC PC meeting on December 7, 2010 • Contacts: • Dmitry Kosterev, dnkosterev@bpa.gov • Alison Silverstein, alison.silverstein@mac.com • Donald Davies, donald@wecc.biz

45. HVDC Modeling

46. HVDC Task Force • Kickoff meeting held on July 12, 2011 • Mission statement: To develop basic building block models and documentation to facilitate the analysis of conventional and voltage-source converter (VSC) based High-Voltage Direct-Current (HVDC) systems in power system powerflow and stability studies for planning studies, when investigating alternative means of transmission.

47. HVDC Task Force (cont.) • Priorities: • VSC-HVDC; point-to-point • Conventional; point-to-point • Back-to-back Conventional • Multi-terminal Conventional • Multi-terminal VSC (no actual installations) • CCC is not presently of high priority (Rapid City back-to-back is CCC) • The task force will start with the VSC and Conventional HVDC models.

48. HVDC Task Force (cont.) • Action Plan: • GE to look into issues reported: • The dynamic models (dcbtb1, dc2t) • The load flow mode 4 & 5 • ABB to look into shared code developed several years ago to be a starting point for the planning conventional HVDC model (with review input from all of course) • VSC – vendors to discuss and get back to group on what they can share as a starting point • EPRI to start a skeleton document for the TF • Report on progress by September 16th

49. Modeling Workshop

50. Modeling Workshop • 2-day workshop: June 21-22, 2011 • Held at WECC offices in Salt Lake City • Over 100 participants (~60 in person, ~40 on phone/webex) • Topics: • Load modeling – composite load model structure and data tools • Load modeling studies – FIDVR, model validation and system impact studies • Generation modeling and validation • Wind generation modeling • Solar generation modeling