MVWG Report to TSS May 2016 Jun Wen, MVWG Chair Southern California Edison

Recent Meetings and Workshops Meeting / WorkshopDate LMTF MeetingFeb 26, 2016 REMTF MeetingMar 2, 2016 PPMVDTF MeetingMar 3, 2016 HVDCTF MeetingMar 4, 2016 MVWG WorkshopMar 8 – 9 am, 2015 MVWG MeetingMar 9 am - 10, 2015

March MVWG Workshop One and half day Workshop covering:  Load Modeling  Renewable Energy Modeling  Generator Modeling, Testing, and Model Validation Workshop material available at Over 60 participants, however, mostly regular MVWG attendees Survey was conducted to see whether a second workshop is of interest and if so what topics

August MVWG Workshop Over 20 responses from different entities/utilities, showing participants and covering a variety of topics MVWG Core Team agreed to have another workshop  Aug 30-31, Portland, hosted by BPA  1.5 day on Load Modeling, 0.5 day on System Model Validation It is not possible to cover all the topics requested, it is encouraged to reach out to software vendors and MVWG members for questions that are not covered by workshop. NERC SMS is hosting Power Plant Model Validation Workshop Sep 20-21, Atlanta.

MVWG Activities Overview and Approval Items Load Modeling Renewable Energy Modeling System Model Validation Generator Modeling, Testing, and Model Validation HVDC Modeling RAS and Relay Modeling Approved Dynamic Model List Next Meetings and Workshops

Load Modeling

Composite Load Model Work Plan 1-2 years  Modular Structure and Flexibility (Plug and Play)  Consistent, robust rules for initialization (phase 1)  Efficient data management  Improved Protection Modeling  Load Model Data tool development  Benchmarking between software programs (phase 1 and phase 2) 2-5 years  Electronically Coupled Load  Improved Air Conditioner Models  Updates to Distributed Solar Generation and Energy Storage Models  Model Validation studies 5-10 years  Collecting and Coordinating load model data  Adopt composite load model for steady state studies 10+ years  Promote composite load model as standard load model for bulk power studies (IEEE wide)

Current Priorities CMPLDW2 Development  Modularization  Distributed Generation  Efficient Data Format CMPLDW Benchmarking Report Power Electronics Models of the future

Efficient Data Format CMPLDW today “Long ID” (LID) is assigned to each load in a power flow case Load model data tool generates dynamic data based on LID+season+ hour

Proposed Efficient Data Format “Load descriptor” proposal Only 60 full cmpldw declarations instead of 10,000 Area and zone cmpldw More to come on data groups

Program Benchmarking Studies The purpose is to ensure performance uniformity among the programs. Benchmark methodology:  Simple 2 bus model  Play-in signal of frequency and voltage at the “system” bus  6 different play-in signals  6 different load models A report is targeted to be completed by June NERC LMTF is planning to do more benchmarking studies.

Composite Load Model Improvements Load Model Data Tool  LMDT2.0 with additional visualization capabilities Load model validation and system impact studies  Continued studies are required Importance of better model spec documentation “Sequential stalling” proposal  Beta version to be implemented and tested

NERC LMTF Task List NERC and WECC LMTF coordination, WECC takes lead on certain tasks

Renewable Energy Modeling

2 nd Generation Model Improvement Problem identified by users: Simulated under frequency relays will trip the units when a close in fault is applied, which shouldn’t happen in reality. Jamie Weber (PowerWorld) suggested to add one global voltage threshold that applies to frequency-based relay models (lsdt9, lhfrt, others), under which the relay should not operate. A typical value of 0.3 in software (compared to a typical value of in relay) is suggested to be used. While this being implemented, it was suggested to turn off the frequency-based relay for this condition.

Enhanced Plant Level Control REPC_B will have additional new features, including interface with multiple WTGs, interface with reactive support devices, and plant level power factor control option. Work in progress.  A benchmark result shows all three programs agreed with each other in principal but there is still minor difference.  Pouyan Pourbeik (PEACE) is investigating and the model is expected for approval at June MVWG meeting

DG Modeling Team agreed that a modular composite load model structure is the top priority. Work in progress, more updates are expected at June MVWG

Others Battery storage model REEC_C benchmark tests underway, by Xiaokang Xu (S&C Electric Company). Spencer Tacke (MID) distributed the Future Modeling Directions survey drafted by Ed Muljadi (NREL) to REMTF and MVWG members.

System Model Validation

System Model Validation Studies Slaven Kincic (PeakRC) presented Jan 21 st Colstrip- Broadview 500 kV events validation studies, which showed reasonable results. System Model Validation TF (SMVTF) and MOD-033 discussions:  Number of cases and case selections are discussed  The group doesn’t believe a case review process is necessary NERC MWG Procedures for Validation of Powerflow and Dynamics Cases, available at (MWG)-2013.aspx (MWG)-2013.aspx

Generator Modeling, Testing, and Model Validation

Excitation Models IEEE Standard was out for re-ballot. MVWG plans to review and update the exciter models following the IEEE standard in effect

Hydro Turbine Governor Model John Undrill has been working with BPA on the hydro turbine governor model.  The model validation was completed for Kaplan and Francis turbine plants – Chief Joseph, Little Goose, and Bonneville.  John will provide the pseudo code and test case for software vendors to implement and test. Shawn Patterson (USBR) and John Undrill suggested to keep the h6b model (approved in 2013) for the updated hydro turbine governor model as no one has used this model Jun Wen (SCE) asked the h6b model spec be updated and a note on h6b added to the WECC approved dynamic model list.

GENROU, GENSAL, GENTPJ, GENTPF John Undrill talked about the history of GENROU, GENSAL, GENTPF, GENTPJ models in the previous meeting  GENSAL comes from limitations of analog computers in late 1950s  GENTPJ and GENTPF come from GENROU but with different saturation calculations. Documentation by Jamie Weber Pouyan Pourbeik, etc. recently submitted a paper on generator modeling that relates genrou, gensal, gentpf and gentpj model back to the origins of fundamental machine theory, and gives clear evidence on the better performance of gentpf and genpj as compared to genrou and gensal, for both round rotor and salient pole machines.

GENROU, GENSAL, GENTPJ, GENTPF GENSAL should not be in use – already retired GENROU cannot capture  Transient dynamics of Ifd properly in all cases (gentpf can)  Steady-state value of Ifd over entire operating range of the machine due to not modeling saturation variations with machine loading (Kis in gentpj) Should consider changing all generators to gentpf at the minimum, and then to gentpj when Kis can be estimated (When Kis=0, gentpj=gentpf) OEM data is used – data does not change, just change the model

Power Plant Testing and Model Validation Steve Yang (BPA) provided an update of PPMVDTF activities Multiple members shared their model validation experiences. More participation to the TF activities is highly encouraged. NERC Reliability Guideline on Power Plant Model Verification using PMUs, very good reference document NERC SMS is hosting a Power Plant Model Validation Workshop in Sep.

Generator Error from UFLS Studies Bo Gong (Columbia Grid) reviewed all 132 generators and summarized the results into 4 categories:  Generators have significant parameter issues and fail the standard tests  Generators have significant parameter issues but not fail (creating unstable situation likely to happen in UFLS) in the standard tests, or can’t tested  Devices (wind, solar, etc) that are ok to be turned off in the UFLS study  Generators don’t have significant parameter issues and succeed in standard tests Suggested Next Step: TSS facilitate a meeting for MVWG and UFLS team to meet and discuss results

HVDC Modeling

Conventional HVDC point-to-point dynamic model  Final memo and model sent to software vendors  Beta implementation and test in progress  Target to have model spec and model for approval in the June meeting VSC HVDC point-to-point dynamic model  The interface between power flow model and dynamic model still needs to be decided  The proposal is to start with voltage source behind reactance model  VSC HVDC point-to-point dynamic model TF memo of 11/19/2013 reviewed by HVDCTF and no update needed LADWP, HVDCTF Chair and MVWG Chair had a conference call with ABB  ABB is working on a dll file for the user written version of IPP model in PTI  ABB is developing a brief high-level block diagram and documentation of IPP and PDCI upgrade

RAS and Relay Modeling

James O’Brien (PNNL) provided a brief update to the transient RAS modeling, and shared the draft of RASTF charter.  RASTF Charter is expected for approval at June MVWG meeting Several utility members volunteered for the RASTF

WECC Approved Dynamic Model List

Terminology updates for clarity:  “not approved” was changed to “never approved”  “un-approved” was changed to “retired” Non-approved models were greyed out. No model is incorrect modeling. If you don’t know what to do, consult with MVWG Concern was raised that it is not clear which version is the latest, Kent Bolton (WECC) asked IT to promote the latest version, so the one shown as the first from search results should be the latest.

Next MVWG Meetings and Workshops

Next MVWG Meetings & Workshops South Regional Hands-on Workshop and 1 st MVWG Meeting  March 8-10 San Diego 2 nd MVWG Meeting  June Salt Lake North Regional Hands-on Workshop  Aug Portland 3 rd MVWG Meeting  Nov Salt Lake

Approval Items Expected in June REPC_B model and model spec LCC model and model spec RASTF charter WECC Approved Dynamics Model List

Questions ?