Solar Resource Performance Task Force (SRPTF) Highlights and...Solar Resource Performance Task Force...

Solar Resource Performance Task Force (SRPTF)

Ryan D. Quint, Ph.D., P.E.NERC Planning Committee MeetingJune 6-7, 2017

RELIABILITY | ACCOUNTABILITY2

Background

Inverter Task Force kicked off ad hoc following identification of August Blue Cut Fire disturbance Key focus on disturbance analysis (and report) Identified recommendations and more work to be done

Inverter Task Force became an OC Task ForceReport findings/recommendations presented at Joint Session Alert being provided for PC/OC awareness prior to release

OC will vote to approve/endorse report


Solar Resource Performance Task Force (SRPTF)

More work to be doneSRPTF is a continuation of work from initial ad hoc TFProposed to become a joint PC/OC TFHeavy focus on planning aspects Continuation of longer-term work identified in report Recommended controls and settings Modeling and system analysis capabilities Industry-coordinated stability analysis

Proposing To create a joint PC/OC task force Scope document provided in meeting materials


SRPTF Scope Document

Activities Review and document frequency and voltage ride-through characteristics

of solar PV; clearly articulate intended performance; clarify “may trip” area Review and document recommended delays for lowest levels of frequency

to ensure transient/distorted waveform “ride through” Explore development of performance based standard for inverter-based

resources, not to be confused with protective relay functions of PRC-024-2 More clearly understand potential limitations in early inverter technology

and document; identify extent to which these limitations can be updated or corrected

Study impacts that inverter momentary cessation for voltage excursions could have on BPS reliability; recommend performance characteristics related to momentary cessation, including voltage level and restore output characteristic



Activities Explore detailed simulations of high penetration solar PV conditions; study

impact of momentary cessation on BPS reliability; develop necessary technical justification for recommended settings

Define expected or recommended operation for solar PV during abnormal operating conditions, including the type of current supplied (active or reactive, positive-negative-zero sequence)

Coordinate with FERC, IEEE, UL, NFPA, state jurisdictions, etc. Coordinate with IEEE 1547 to ensure coordinated response of inverter

technology



Deliverables Reliability guideline on solar PV (and other inverter-based resources)

performance Recommendations on solar PV performance and any modifications to

standards related to control and dynamic performance during abnormal grid conditions

Detailed studies of high penetration of solar PV Webinars, workshops, lessons learned, etc., as applicable Other activities specified by NERC PC/OC, coordinated with SC



Membership Original TF members and other members selected by NERC PC and OC Should have expertise in the following areas:o Understanding of inverter design, controls, and manufacturing for solar PV and

other inverter-based resourceso Plant-level controls and relationship between these controls and invertero Inverter-based resource performance characteristicso Performing transient stability simulations and modeling of solar PV and other

inverter-based resources, including modeling and model parameterso Performing model verification testing for inverter-based resourceso BPS angular, voltage, and frequency stability, particularly under high penetration

of inverter-based resources TF will consists of two co-chairs appointed by PC and OC Decisions consensus-based led by co-chairs and staff coordinators



Duration Expected to exist no more than 18 months to develop deliverables listed Will submit work plan to PC and OC, which must be approved by both

technical committees

Meetings Expected to have 2-3 in-person meetings, supplemented with conference

calls to continue workload throughout year


Concluding Remarks

Most activities pulled nearly directly from disturbance reportDeliverables enable documentation of more detailed topics that

initial TF did not have time to focus on – longer-term effortsTransitioning from OC TF to Joint PC/OC TFSeeking approval of the creation of this new TF (formally) and

approval of the scope document for the TF


GMD Standards UpdateProject 2013-03 Geomagnetic Disturbance Mitigation

Frank Koza, PJM InterconnectionPlanning Committee MeetingJune 6-7, 2017


• Background: FERC Order No. 830 directs NERC to revise the GMD planning standard

• Geomagnetic Disturbances (GMD) Standards Drafting Team (SDT) discussed revisions to TPL-007 with the GMD TF during May webinar

Informational Updates


FERC Order No. 830

…the Commission approves Reliability Standard TPL-007-1 as just, reasonable, not unduly discriminatory or preferential and in the public interest. While we recognize that scientific and operational research regarding GMD is ongoing, we believe that the potential threat to the bulk electric system warrants Commission action at this time, including efforts to conduct critical GMD research andupdate Reliability Standard TPL-007-1 as appropriate.

U.S. Federal Energy Regulatory Commission (FERC)September 2016


• Order No. 830 directs NERC to revise TPL-007 to address Commission concerns Modify the benchmark geomagnetic disturbance (GMD) event definition

used for GMD assessments Require entities to collect GMD data for model validation purposes Establish deadlines for Corrective Action Plans (CAPs) and mitigating

actions to address identified GMD impacts

• Revisions must be filed by May 2018

Revisions to TPL-007


• TPL-007-1 addresses risks of voltage collapse and equipment damage in the Bulk Electric System (BES) caused by GMD events

• Applicable Entities: Planning Coordinators and Transmission Planners—perform

geomagnetically-induced current (GIC) calculation and network analysis (Vulnerability Assessments)

Transmission Owners—assess extra high voltage transformers (Wye-grounded on high side, 200kV and higher)

Generator Owners Owners—assess extra high voltage transformers (Wye-grounded on high side, 200kV and higher)

A brief review of TPL-007-1…


• Components of TPL-007-1 Benchmark GMD event GMD Vulnerability Assessment Transformer Thermal Assessment CAP

• Implementation phased in over five year period beginning January 2017 (R1 compliance date: July 1, 2017)

A brief review of TPL-007-1…


FERC Directive on GMD Benchmark

The Commission approves the reference peak geoelectric field amplitude figure proposed by NERC. In addition, the Commission… directs NERC to develop revisions to the benchmark GMD event definition so that the reference peak geoelectric field amplitude component is not based solely on spatially-averaged data.

-Order No. 830 P 44

• The SDT is developing a Supplemental GMD Event based on peak (non-averaged) geoelectric fields


• The regional geoelectric field peak amplitude, Epeak, to be used in calculating GIC in the GIC system model can be obtained from the reference value of 17 V/km using the following relationship:

Epeak = 𝟏𝟏𝟏𝟏∗ × 𝜶𝜶 × 𝜷𝜷 (V/km)α = Factor adjustment for geomagnetic latitudeβ = Factor adjustment for regional Earth conductivity

• * 17 V/km is based on Los Alamos National Labs (LANL) report of August 2015. SDT is conducting statistical analysis which could change the value used for the supplemental assessment

Proposed Supplemental GMD Event


• TPL-007-2 includes requirements for entities to perform a supplemental GMD Vulnerability Assessment using this event

• CAP would NOT be required (like TPL Extreme Event category) and the methods for applying the supplemental GMD benchmark are left to the planners If analysis concludes there is Cascading, responsible entities are required

to evaluate mitigating actions

Proposed Supplemental GMD Event


Revision to Thermal Assessment

…the Commission directs NERC to revise Requirement R6 to require registered entities to apply spatially averaged and non-spatially averaged peak geoelectric field values, or some equally efficient and effective alternative, when conducting thermal impact assessments.

-Order No. 830 P 65

• TPL-007-2 includes a new requirement (R10) to meet the directive


• Key differences with requirement (R6) for benchmark thermal assessments: Based on a supplemental GMD event

waveform (with local enhancement) Screening criterion is 85 A per phase.

i.e. if GIC will exceed this value then the supplemental thermal assessments must be performed

Supplemental Thermal Assessments

5 minutes

Geomagnetic Field Waveform For Thermal Assessment (Expanded View)


• TPL-007 requires CAP when system does not meet performance for the benchmark GMD Vulnerability Assessment

• Options include Hardening the system Operating procedures and installing monitors

• Order No. 830 directs revisions to establish CAP deadlines (P 101)

Corrective Action Plan Deadlines


• TPL-007-2 includes a revised CAP requirement (R7) to meet the directive One year for development of CAP Two years for implementing operating procedure mitigation Four years for implementing hardware mitigation

• Revisions to CAP deadlines must be reported to Reliability Coordinators and affected entities with updates on an annual basis until completed

Revised CAP Requirement


GMD Data Directive

The Commission … adopts the NOPR proposal in relevant part and directs NERC to develop revisions to Reliability Standard TPL-007-1 to require responsible entities to collect GIC monitoring and magnetometer data as necessary to enable model validation and situational awareness, including from any devices that must be added to meet this need.

-Order No. 830 P 88


SDT developed Requirement R11 to meet the GIC data directive.

• R11. Each responsible entity, as determined in Requirement R1, shall implement a process to obtain GIC monitor data from at least one GIC monitor located in the Planning Coordinator's planning area or other part of the system included in the Planning Coordinator's GIC System model.

GMD Data Process Requirements


SDT developed Requirement R12 to meet the magnetometer datadirective.

• R12. Each responsible entity, as determined in Requirement R1, shall implement a process to obtain geomagnetic field data for its Planning Coordinator’s planning area.



• Sources of geomagnetic field data include: Observatories such as those operated by U.S. Geological Survey, Natural

Resources Canada, research organizations, or university research facilities Installed magnetometers Commercial or third-party sources of geomagnetic field data

• Geomagnetic field data products from government or research organizations can meet the requirement when magnetometers are not located in the planning area



• Targeting initial posting for formal comment (45-days) during Summer 2017 Initial ballot during last 10-days of commenting

• SDT is keeping GMD Task Force informed of progress• Standards must be filed by May 2018• Refer to NERC website, Standards Under Development:

Project 2013-03 GMD Mitigation

Next Steps in Standards Development

http://www.nerc.com/pa/Stand/Pages/Project-2013-03-Geomagnetic-Disturbance-Mitigation.aspx


Reliability Assessment SubcommitteeStatus ReportPhil Fedora, RAS ChairPlanning Committee MeetingJune 6-7, 2017


Reliability Assessment SubcommitteeOutline

Summary• 2017 Summer Reliability Assessment • 2017 Long Term Reliability Assessment• Probabilistic Assessment Working Group• EIA Solar Photovoltaic Presentation• Enhancing Deterministic Metrics• Essential Reliability Services Working Group Update• Single Point of Disruption on Natural Gas Infrastructure • Regional RoundtableSchedule


Reliability Assessment Subcommittee2017 Summer Reliability Assessment

Assessment Finds Resources Adequate for 2017 SummerATLANTA – Anticipated bulk power system resources in North America are sufficientto meet summer electricity demand for 2017, NERC concludes. Most regions areexpected to meet their NERC-recommended reference levels for reserve margins.As a result of increased hydro supply in California, the state is not expected to relyas much on natural gas resources. The August 21 solar eclipse is not expected toimpact the reliability of the bulk power system.


Reliability Assessment Subcommittee2017 Long-Term Reliability Assessment


Reliability Assessment SubcommitteeProbabilistic Assessment Working Group

• Chair and Vice Chair• Work Plan• Survey Request

Probabilistic Studies Survey Request

REGIONAL EXECUTIVES

FRCC — Ms. Stacy Dochoda SERC — Mr. Gary J. Taylor MRO — Mr. Daniel P. Skaar SPPRE— Mr. Ron Ciesiel RF — Mr. Timothy R. Gallagher Texas RE— Mr. Lane Lanford NPCC — Mr. Edward A. Schwerdt WECC— Mr. James B. Robb

Probabilistic Studies Survey: Click here Dear Regional Executives: In an effort to improve NERC’s continuing probabilistic assessments, the NERC Planning Committee (PC) tasked the Probabilistic Assessment Working Group (PAWG) to develop Technical Reference documents that identify and evaluate more probabilistic approaches for ongoing analyses that will provide further insights into resource adequacy assessment. The objectives of the PAWG include conducting the biennial NERC Core Probabilistic Assessment and supporting the development of NERC coordinated Special Probabilistic Assessment reports, including the development of proposed data and information requests The NERC Reliability Assessment Subcommittee (RAS) is requesting your assistance in assessing the probabilistic resource adequacy studies of your Region. This probabilistic studies survey put forth by members of the PAWG seeks information on probabilistic approaches done by your Region for ongoing analyses and future plans for further insights into resource adequacy assessment. Please see the above survey link. Regions and Assessment Areas are highly encouraged to send the survey to their Balancing Authorities (BAs) and entities. Survey responses are due on May 25, 2017 (COB). Related materials have been posted on the NERC website:

• PAWG Scope of Work Document • PAWG Draft Work Plan

On behalf of NERC’s Planning Committee and the Reliability Assessment Subcommittee, thank you for your continues support in the NERC’s Reliability Assessments.


Reliability Assessment SubcommitteeEIA Solar Photovoltaic Presentation

Key takeawaysThere are several survey forms used to collect solar photovoltaic (PV) capacity

Different types of entities report solar PV capacity data (Third Party Owners and utilities)

EIA reports small-scale and utility-scale solar PV capacity and generation versus “distributed solar PV”

Solar PV capacity can be part of a net metering program

Monthly capacity data is used to estimate small-scale solar PV capacity and generation for publication in the Electric Monthly Power


Enhancing Deterministic Metrics

Enhancing Deterministic Metrics Challenges with Reserve Margins and Reference Margin Levels

Reliability Assessment Subcommittee MeetingApril 12, 2017


Reliability Assessment SubcommitteeApril Meeting Overview

• Essential Reliability Services Working Group Update

• Single Point of Disruption on Natural Gas Infrastructure Preliminary results

• Regional Roundtable Discussion of emerging reliability issues


Reliability Assessment SubcommitteeSchedule

• July 11-12 – LTRA Peer Review BPA – Portland, OR

• August 22-23 – Review WRA NSPI – Halifax, NS

• November 14-16 – Review LTRA FRCC – Tampa, FL


Single Point of Disruption on Natural Gas InfrastructureSpecial Assessment

Thomas Coleman, Director, Reliability AssessmentPlanning Committee MeetingJune 6, 2017


Overview and Background

• Assessment Scope and Driver• Advisory Group Update (subgroups)• Facilities Identification• Impact and Risk Analysis


Date DeliverableSeptember 15-16 Draft Scope Presented to OC and PCOctober 19 Advisory Group ActivatedFebruary 20 Currently Available Studies Due to NERCMarch 31 Gas Fired Generation Data Due to NERCApril -

AssessmentDevelopment

- Power System Study- Resource Adequacy- Gas Section (Earthquake, interruptiblity, contracts, etc.)- Formation of Recommendations

-MayJune 6 Key Findings Presented to PCJune 17 Draft Assessment Report Sent to RAS, PC, OC for reviewJune 21 NERC Editor ReviewJuly 5 NERC Executive Management ReviewJuly 24 Report Sent to NERC Board of Trustees for ReviewAugust 9-10 NERC Board of Trustees Vote to Approve ReportAugust 15 Target Release

SPOD


• Increased dependence on natural gas for generating capacity can amplify the bulk power system’s (BPS) vulnerability to disruptions in fuel supply, transportation, and delivery.

Gas – Electric Interdependency

Risk To Bulk Power System

Reliability

Interruption (Fuel Contracts)

Wholesale Electricity Market

Utility, Integrated Resource Plan,

State Commission

Curtailment (Physical

Disruption)

Resiliency Planning

(All Hands)

Threat Solution Space


Drivers that impact Natural Gas

Threats to natural gas system infrastructure and operations thatcould impact BPS reliability:• outage of large or key storage facilities, • pipeline segment• LNG terminal• Compressor stations (~6% use only electricity) – mostly due to

environmental and clean air regulations• Other: earthquake, flooding, extreme cold, drought, regulatory action, physical or

cyber attack


Transmission and Electricity Deliverability

Why is a transmission analysis required?

Identification of affected electric

generation

• Due to loss of natural gas supply or transportation

Methods and Assumptions

• Taking into consideration:• duel fuel capability, natural gas rerouting, cross

pipe gas injection• DSM, non-critical load shed

Transmission and Power

Transfer Analysis

•Reserve sharing groups•Adequate Resources internal to BA

or assistance from neighboring BAs• If needed, Development of

Operational Procedures


All Underground Gas Storage


NERC’s Annual Long-Term Projection

2009 LTRA

2011 LTRA

2013 LTRA

2015 LTRA

320

330

340

350

360

370

380

390

400

410

420

430

440

450

460

470

2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019

GWTotal NERC-Wide On-Peak Gas-Fired Capacity


Preliminary Recommendations & Findings

• Data gaps – Need for a databank for Planning and Operation Assessments

• Need for periodic review and assessment with the change in resource mix

• Interruption risks apparent only in market areas; curtailment risks are everywhere with significant gas generation

• Having firm transportation does not guarantee service during extreme conditions including the outage of key facilities

• Not all gas generators have dual-fuel capability, not all have oil onsite inventory, not all can be hot swapped, not all are successfully restarted, not all can operate more than 3 days.

• All systems can currently accommodate some level of generation loss due to loss of fuel.


Pipelines, Storage, and LNG Facilities


Changing Resource Mix Drives Changes to Fuel Risk Profile

Natural Gas Plants• Just-in-time fuel• Minimal back-up fuel inventory if

maintained• Can be vulnerable to common-

mode failure

Coal Plants• 30-90 days on-site fuel inventory• Long-term fuel supply contracts• More resilient to fuel supply

disruptions


Pipeline Perspective

• Pipelines will interrupt power generation without contracts• A variety of contracting options available to accommodate

unique generator characteristics• Under severe conditions, even firm contracts may be curtailed• Additional infrastructure will not be constructed without an

identified need (firm contract)


• Maintain Fuel Security Maintain fuel and resource diversity Maintain firm fuel supply and transportation Maintain dual-fuel capability Maintain on-site fuel back-up inventory

• Resiliency Planning for Large Disruptions Evaluate largest/multiple facility outages regardless of likelihood State and Electric (e.g, ISO/RTO, local utility) partnerships Incentives and rules in market areas Security and risk assessment

• Enhance Situational Awareness System operator intelligence on fuel inventories, contracts, shipments Coordination with pipeline operators

Solutions and Objectives for Ensuring Electric Reliability


• Mitigation measures – use of dual-fuel generators and fuel firming; air permit waivers

• Risks to natural gas generation during summer season – not just a winter problem

• Expand gas-electric planning and coordination – current industry best practice in some areas

• Operational coordination between gas and electric industries decrease likelihood of wide-spread outage

• Mitigation Measures: battery storage, transmission capacity, incremental generation, demand side reduction

Key Findings and Recommendations


Open Distribution

NATF Update for NERC PC Meeting

Lee UnderwoodProgram Manager, Practices

Open DistributionCopyright © 2017 North American Transmission Forum. Not for sale or commercial use. All rights reserved.

Open Distribution

Topics

• Activities in System Protection Practice Group• Geomagnetic Disturbance Webinar• Recently released and pending public documents• Modeling Practice- Distributed energy resources

working group• Joint NERC/NATF Modeling Practices Workshop• Resiliency Initiative• NATF activities related to ERO Reliability Risk

Priorities

Open Distribution

NATF System Protection Practices Group

• Almost 1000 member SME’s• Web meetings held on 4th Thursday of each

month, 11-12:30 Eastern• Active projects and working groups

– Protection Systems Maintenance (PRC-005) Implementation

– Protection Systems Commissioning Practices– Protection Systems Data Management– IEC 61850 Applications– Misoperations Data Collection and Analysis

CONFIDENTIAL – Restricted Distribution

System Protection Workshop

• Held May 17-18 at Dominion Virginia Power• 69 attendees from 32 companies• Topics

– Security and CIP impacts on system protection– Automating operational analysis and data visualization– System protection coordination– Protection system data storage and workflow– Commissioning practice document overview and break out sessions– Operational analysis and PRC-004 compliance processes– NATF protection system performance metrics

CONFIDENTIAL – Restricted Distribution

System Protection Training

• Web-based training developed by System Protection Practice Group members

• Incorporate examples of misoperations where possible• Past topics

– Directional Comparison Blocking Scheme Settings– Directional Control Settings

• Recent topics– Breaker Failure Relay Settings- 168 attendees– Impact of Source-to-Line Impedance Ratio on Protection Performance-

215 attendees

• Upcoming– Ground Fault Protection Issues, Methods, and Settings

Open Distribution

Geomagnetic Disturbance Webinar

• Held April 5, 2017• Case study of one

member’s hazard assessment, GIC analysis, and mitigation plans

• 300+ attendees

Open Distribution

Recently Released and Pending Public Documents

• Bulk Electric System Monitoring and Control - An Overview of Backup Capabilities

• TPL-001-4 Modeling Reference Document• MOD-033 Methodology Reference Document• BES Operations Absent EMS and SCADA Capabilities -

a “Spare Tire” Approach–Pending approval• EMS External Model Reference Document–Pending

approval• Transient Cyber Asset Implementation White Paper–

Pending approval

Open Distribution

Modeling Practice- DER Working Group

• Modeling distributed energy resources (DER) to assess impact on transmission

• Data sources for DER• Amount of DER to be modeled• Operating Experience and Lessons Learned• Modeling and studies practices document

development

Open Distribution

Joint NERC/NATF Modeling Practices Workshop

• Scheduled for June 20-21 in Chicago• Agenda

– Dynamic Load Modeling– Power Plant Modeling – Model Validation and MOD-033 – Integrating Renewables at the Transmission Level – Modeling Distributed Energy Resources – General Session: NERC/FERC update, NERC

modeling updates, emerging modeling issues

Open Distribution

Resiliency Initiative

• Two joint NATF/EPRI resiliency summits per year– System restoration– Severe weather and other natural events– Interface with government and other emergency

response agencies– EMP– Security

• Next summit – October 17-18– Tri-State G&T, Westminster, CO

Open Distribution

RISC items- Major areas of NATF involvement

• Risk Profiles Cybersecurity Vulnerabilities Changing Resource Mix Bulk-Power System Planning Resource Adequacy and

Performance Loss of Situational

Awareness Physical Security

Vulnerabilities Extreme Natural Events Asset Management and

Maintenance Human Performance and

Skilled Workforce

11

• Themes and Takeaways from Risk Profiles Resiliency and Recovery Adequate Data Visibility Accurate Models Natural Gas

Deliverability Spare Equipment

Strategy

Major areas of NATF involvement:

1. Asset Management2. Human Performance and

Skilled Workforce3. Resiliency (includes Cyber

and Physical Security and Extreme Natural Events)

Open Distribution

QUESTIONS?

12

System Analysis and Modeling Subcommittee (SAMS) Update

Michael R. Lombardi, SAMS ChairPlanning Committee MeetingJune 6-7, 2017


SAMS Update June PC MeetingOutline

Summary• Distributed Energy Resource Modeling (separate PC agenda item)• Plant-level Control and Protection Modeling (separate PC agenda item)• Integrating VER into Weak Grids (separate PC agenda item)• Joint NATF-NERC Modeling Workshop• Node-Breaker Representation in Planning Models• Three Phase Modeling of Transmission Networks• Modeling Notification• ERS Measure 7 Data Analysis (completed) • Generator Protection Model Implementation• Development of Interconnection-wide Models and Planning Practices

(new)


SAMS Update June PC MeetingDER / Plant Controls / VER

• Draft Reliability Guideline: Distributed Energy Resource Modeling (separate PC agenda item) Seeking Approval for 45 Day Comment Period

• Technical Reference Document: Plant-level Control and Protection Modeling (separate PC agenda item) Seeking Final Approval

• Draft Reliability Guideline: Integrating VER into Weak Grids (separate PC agenda item) Seeking Approval for 45 Day Comment Period


SAMS Update June PC MeetingJoint NATF-NERC Workshop

• Joint NATF-NERC Modeling Workshop When: June 20-21, 2017 Where: Exelon/ComEd in Oak Brook, Illinois (Chicago) Planned topicso Dynamic Load Modelingo Power Plant Modelingo Model validation and MOD-033o Integrating Renewables at the Transmission Levelo Modeling DER (renewables at the distribution level)o Catch all session: NERC/FERC update, NERC modeling updates, Emerging

modeling issues


SAMS Update June PC MeetingNode-Breaker

• Node-Breaker Representation in Planning Models Supporting advancement of node-breaker representation in planning

models and alignment between planning and operations caseso Gather Experience and Lessons Learned - TCD: Q2-2017o Small-scale pilot of node-breaker implementation (NPCC, WECC, SERC, RF) - TCD:

Q4-2018o Wide-scale construction of planning base case with full node-breaker capability

by MOD-032 Designee - TCD: Q4-2020


SAMS Update June PC MeetingThree Phase Modeling

• Technical Reference Document: Applications for Three Phase Modeling of Transmission Networks Three phase modeling of the power system to address:o Detailed generator interactionso Inverter-based generation interactions

TCD: Q2-2018


SAMS Update June PC MeetingModeling Notifications

• Modeling Notification (Under Development) Gas Turbine Governor Modeling Load Model Benchmarking Renewable Energy System Modeling


SAMS Update June PC MeetingERS Measure 7

• ERS Measure 7 Data Analysis (Completed) NERC Performance Analysis Subcommittee (PAS) collected ERSTF Measure

7 data from BAs across the NERC footprint SAMS sub-team was created to review Measure 7 data Conclusions and recommendations to ERSWG, which included:o Data did not establish a trendo Reactive power by area was not useful as reactive power is a relatively localized

issueo Did not capture how area dependency or contingency dependency relate to

reactive reserveso Curtail the use of Measure 7 (reco)o Use the Reliability Guideline for Reactive Power Planning to advocate reliable

reactive power planning practices (reco) ERSWG Action (separate PC agenda item)


SAMS Update June PC MeetingGenerator Protection Modeling

• Generator Protection Model Implementation Expansion of dynamic models per PCPMTF Recommendationso Loss of field protectiono Under- and over-voltage and frequency protections (already included in the

model)o Turbine power and load unbalance protection o Voltage restraint over-current protection (revise the stator-over current

protection model)o V/Hz Limiter and protection

TCD: Q3-2018


SAMS Update June PC MeetingModeling and Planning Practices

• Assessment of Practices for Development of Interconnection-wide Models and Planning Practices (New) Review and assessment of practices, e.g.,:o generation dispatcho demand responseo firm transferso demand levels

Identify areas for improvement or consistency TCD: Q1-2018


MOD-032 Case Improvements TrackingRyan D. Quint, Ph.D., P.E.NERC Planning Committee MeetingJune 6-7, 2017


• Purpose

• NERC designated Regional Entities as “MOD-032 Designees”• Specified Functions and Attributes in signed Designee

Agreements, such as: Case creation manual Feedback process for recurring data or model issues Direct to use standardized model lists Processes for case correction

MOD-032 Background

“establish consistent modeling data requirements and reporting procedures fordevelopment of planning horizon cases necessary to support analysis of thereliability of the interconnected transmission system”


• Many moving parts in modeling arena• Needed a way to track NERC assessments of models Modeling issues Recommendations on model corrections Designee implementation of recommendations Documentation of differences Assurance of feedback process

• MOD-032 Case Improvements Tracking Document will be a living document between NERC and the MOD-032 Designees to help track and document collaborative efforts towards case improvement

Case Improvements Tracking


• Identified metrics• Assessment of metrics on planning cases• Identified systemic issues to be addressed• Clear documentation of known modeling errors (bad data) and

potential modeling issues (suspect data)• All identified issues and scripts provided to MOD-032 Designees

for their own tracking and follow-up action• Expectation that MOD-032 will proactively address these modeling

issues• Appendix tracks how each Designee has added the metrics to their

case creation process

Case Quality Metrics Assessments


Case Metrics Assessment Metric Classification


Case Metrics Assessment Implementation Tracking Example


• Relying on MOD-033-1 implementation to support case fidelity across all interconnections

• In addition, NERC-identified areas of fidelity improvement based on various assessments: Interconnection-wide system analysis NERC Event Analysis NERC technical committee activities Other simulations and modeling efforts

• Actionable recommendations

Case Fidelity Assessments


• Requirement in Designee Agreements• Designee can either: Direct use of the NERC List of Acceptable Models OR Implement their own list that is more restrictive

• Any deviations (less restrictive) from this should be documented by the Designee in the tracking document and validated by NERC and the MOD-032 Designee

• MOD-032 Designees expected to “enforce” these lists through their case creation process

Implementation of NERC List of Acceptable Models


• NERC assessment of today’s status

• Overall in good shape as a NERC footprint• Identified areas for improvement• Proactive action to improve those issues• Setting a new status quo for ourselves as an industry Will take time, but will be worth the effort

30,000 Foot Level

Table 5.1: Modeling Improvements Overview Topic Eastern Interconnection Texas Interconnection Western Interconnection Case Quality (Steady-State) Satisfactory Improving Satisfactory Case Quality (Dynamics) Issues to be Addressed Issues to be Addressed Issues to be Addressed Case Fidelity Issues to be Addressed Satisfactory Satisfactory Approved Model List Satisfactory Improving Satisfactory


Important Takeaway - Timeline

Status Quo

End Goal

This took a lot of work by many…

- Assessments- Processes- Coordination- Etc.

THANK YOU!

And we’ve got a long way to go…!

Some low hanging fruit

Some longer-term goals


Essential Reliability Services

Brian Evans-Mongeon, ERSWG Co-Chair; Mark Ahlstrom, ERSWG MemberNERC Planning and Operating Committee MeetingsJune 6-7, 2017


ERSWG: In the beginning…

• The 2013 LTRA raised reliability concerns regarding the changing resource mix and recommended that NERC “develop a new approach and framework for the long-term assessment

of Essential Reliability Services to supplement existing resource adequacy assessments”

• ERSTF was chartered by the NERC OC & PC in 2014 Develop methods for identifying and assessing reliability impacts of the

changing resource mix Inform industry and policy makers Develop/recommend Standards, Reliability Guidelines or Technical

Reference documents as necessary


2014 ERSWG Deliverables

http://www.nerc.com/comm/Other/Pages/Essential-Reliability-Services-Task-Force-(ERSTF).aspx

• Built upon the work done by the Interconnected Operations Services Subcommittee 2000/2001

• Intended to provide awareness for regulators and policy makers

• Identified and defined the set of Essential Reliability Services Voltage Support Frequency Supporto Disturbance responseo Load following/Ramping



• Recommended potential measures for evaluating reliability impacts as a result of the changing resource mix Frequency disturbance response Ramping and balancing impacts Voltage Support

• Included general recommendations, such as Monitoring of measures and investigation

of trends New resources should have the voltage &

frequency support capability Increasing DER penetration warrants

additional examination• Developed Policy Maker Briefing and ERS

Tutorial videos.http://www.nerc.com/comm/Other/Pages/Essential-Reliability-Services-Task-Force-(ERSTF).aspx




2016 activities included:• Collecting data and testing of recommended

measures along with preliminary development of Sufficiency guidelines Concluded that “Sufficiency Guidelines are processes

rather than specific values”, i.e., methods of assessing and trending certain aspects of essential reliability services.

• Preliminary investigation into DER related issues DER report intended to heighten awareness of unique DER

issues & challenges


ERSWG Deliverables



ERSWG 2017 Focus

ERSWG Scope Key Points• Continue the development and refinement of ERS Sufficiency Assessments (no

longer to be called Sufficiency Guidelines). This includes:• Ongoing analysis of current & historical trends

• Observations and results to be included in the annual State of Reliability (SOR) Report

• Development of forward looking (predictive) analyses of ERS.• Observations and results to be included in the Long Term Reliability Assessment (LTRA)

• Follow up on DER recommendations


ERSWG On Going Activities

• Measures 1 through 4 - Frequency Collecting and analyzing Synchronous Inertia trends for the four interconnects -

done Testing Rate of Change of Frequency Calculations (RoCoF) Evaluating historical frequency excursion events with more granularity Bringing together efforts of EIPC, UT-Knoxville, and NERC for forward trending Measure 3 for BA, under new examination regarding value and continuation

(historic only)

• Measure 6 - Ramping and Balancing Trending historical CPS1 scores by BA as a screen for historical/current ramping

issues ERS and RAS have established an Ad Hoc group to investigate forward trending

perspectives for ramping Discussions on the need for enhanced load- and weather-related forecasting is

being considered


ERSWG On Going Activities

• Measure 7 - Voltage Tested Reactive Analysis methods (SAMS) and deemed them relatively

inconclusive due the local nature of reactive issues. Recommending (and requesting PC/OC endorsement ) of

discontinuance of Measure 7 SAMS developed Reliability Guideline for Reactive Power Planning

http://www.nerc.com/pa/RAPA/rg/ReliabilityGuidelines/Reliability%20Guideline%20-%20Reactive%20Power%20Planning.pdf

• DER Recommendations Developing SAR to modify MOD-032 to remove LSE and add DP Developing Technical Brief on DER data needs for TPs, BAs, RCs


ERSWG 2017 Summary

Key items for 2017• Test/Validate current measures/assessment methods• Further develop “forward looking” methods of assessment• Determine policy maker needs and develop necessary

briefing documents • Prioritize and develop DER related reference

documents/reliability guidelines• Provide status updates and technical briefs, as appropriate.



Appendix


EI Synchronous Inertia

1


ROCOF Calculation

Rate of Change of Frequency after RCC is determined as:

where, KEmin is minimum inertia (kinetic energy), KERCC is inertia of RCC(Resource Contingency Criteria). Note that this is a simplified equation thatneglects load damping. Should load damping data become available for eachinterconnection, it’s effect can be easily included in the RoCoF calculation.

• Measured as the frequency deviation within the first 0.5 second (i.e.RoCOF/2) after RCC.

• The goal is to avoid a ROCOF that reaches UFLS set points prior to governor response.

1


ROCOF Calculation

1

Reference: Essential Reliability Services Framework Report, November 2015http://www.nerc.com/comm/Other/essntlrlbltysrvcstskfrcDL/ERSTF%20Framework%20Report%20-%20Final.pdf


Interconnection Frequency Performance Events have been selected and 1st

report to be provided April RS meeting.

Trending of Frequency Response

More Granular Trending• A-B frequency response Conventional f response

• A-C frequency response Inertial, load & initial governor

response

• C to B ratio Governor responsiveness

• C’ to C ratio Governor withdrawal


Eastern Interconnection Outreach

Eastern Interconnection Modeling Improvements

Olushola J. Lutalo, MS, P.E., PMP, Senior Engineer of System AnalysisMohamed Osman, P.E., Senior Engineer of System AnalysisNERC Planning Committee MeetingJune 6-7, 2017


• Frequency Response(FR) study model findings• FR dynamics modeling recommendations• Communication/feedback loop to model designee/Generator

Owners • Benchmarking with recent event (Millstone Generation) as part

of model validation using the; 2015 Series ERAG/MMWG 2021 Light Load Base Case 2016 Series ERAG/MWWG 2017 Light Load Base Case

Frequency Response Modeling Improvements Overview


• It was not possible to obtain a valid initialization after running the ERAG/MMWG provided files on the 2015 Series ERAG/MMWG 2021 Light Load Base Case.

• The required DLL models were not made available for the DC Equivalents with the base cases.

• There is no deadband modeling for the most used PSS/E models.• Secondary Frequency Response modeling is inadequate. • Several parameters remained severely out of tolerance over the

60 second no-disturbance simulation.

2015 Series Frequency Response Dynamic Model Findings


• The required DLL models must be made available for the DC Equivalents with the base cases.

• Modeling data submitted by all entities must be supplied to (ERAG)/MMWG in a consistent PSS/E Version.

• PTI should add deadbands in the speed signal of the turbine-governor (TG) models in the PSS®E Library. Make use of these revised models in future frequency responsive models.

• Most used governor models are the TGOV1, TGOV2, TGOV3, TGOV4, TGOV5,IEESGO, IEEEG1, and GGOV1.

• Convert the GENSAL and GENROU models to the GENTPJ model – to accurately model magnetic saturation characteristics

• EX21BR model should be used to represent the EX2000, EX2100, or EX2100e excitation system – modeling of field current limiter

2015 Series Frequency Response Dynamic Model Recommendations:


• Synchronous generating unit within each Region should be assigned one of three possible classifications of governor response/modeling parameters; “Fully Responsive” – The plant power output is fully sensitive to grid

frequency in accordance with the primary control action of the governor, with other plant control elements supporting the action of the governor

“Squelched” – The power output is adjusted by the governor but the adjustment is overridden by the supervising action of a plant 'load controller' that returns plant output to a scheduled value within 10-20 seconds. o Modify the Reset Gain—Available on for the GGOV modelso Change the LCFB1 Outer Loop Controller setting.

“Non-responsive” – The power output changes minimally in the first few seconds after the disturbance

Deadband settings of +/-0.036 Hz are recommended Synchronous generation with droop setting of 5% are recommended



• Non – synchronous generating unit (wind) within each Region should have the following parameters model appropriately relative to the capabilities of the technology and vendor recommendation (Kpg, Kig) - Proportional gain for power control (pu) fdbd1, Deadband for frequency control, lower threshold (<=0) fdbd2, Deadband for frequency control, upper threshold (>=0) Ddn, droop for over-frequency conditions (pu) Dup, droop for under-frequency conditions (pu) Tft, Lead time constant (s) Tfv, Lag time constant (s) Kp, Reactive power PI control proportional gain (pu) Ki, Reactive power PI control integral gain (pu)



Approval/Analysis and Posting Process Feedback Cycle

Feed

back

Tra

ck

Depending on the

Notification

GOs

TOs/ TPs

BAs/ PCs

Model Builders

Modeling NotificationsApproved by

Planning Committee

Modeling NotificationApproval/Analysis and

Posting Process

Periodic Review of Modeling Notifications


• Methodology for benchmarking basically compared the RoCof and Points A, B, and C on the FR of the dynamic models to the FNET data for the Event. The RoCoF compared very well for the Primary Frequency Response (PFR)

period. Point A and Point C on the FR curves benchmarked very well during the

PFR period. Point B on the FR curve benchmarking showed an improvement due to the

recommended change of Governor and Load Controller Modeling

Benchmarking to Recent system Outage events,


Oscillations in Millstone May 25, 2014 Event Benchmark to 2015 Series FR Case

59.9

59.92

59.94

59.96

59.98

60

60.02

0 10 20 30 40 50 60

Freq

uenc

y (H

z)

Time (Seconds)

Millstone EI_ May 25, 2014 Event FNET Benchmark2021 LL 2015 Series FR Base Case (DUK, TVA, SOCO)

EI_FNET.F FREQ 500 kV 346 SOCO FREQ 500 kV 342 DUK FREQ 500 kV 347 TVA

Millstone EventBus (BAU) ModelingOscillations

Millstone Event FNET Data


(Median) Millstone May 25, 2014 Event Comparison to 2016 Series FR Base Case

Millstone Event FR Base Case Modeling

Millstone Event FNET Data


(Median) Millstone May 25, 2014 Event 2016 Series Replace FR Sync. Gen. Case

Add FR Non Synchronous Generation

Reduce Sync. Gen


FR Dynamic Modeling Improvements Conclusion

• 2016 dynamic case initialized well for no-disturbance simulation

• 2016 Series ERAG/MMWG dynamic cases solves for large contingencies

• 2016 Series ERAG/MMWG 2017 Lightload FR dynamic case benchmark very well to the FNET data for the loss of Millstone unit 2 (870MW) and Millstone unit 3(1,233 MW)

• 2016 Series ERAG/MMWG Cases perform better for secondary frequency response study

• Synchronous generation governor have been modeled to capture the following governor response Fully Responsive Squelched Non-Responsive


Reliability Guideline: DER ModelingApproval for Industry Comment

Ryan D. Quint, Ph.D., P.E.NERC Planning Committee MeetingJune 6-7, 2017


Preface

Table 1: Example of U-DER and R-DER Requirements

Criteria Description Threshold

U-DER Modeling Gross aggregate nameplate rating of an individual U-DER facility directly connected to the distribution bus or interconnected to the distribution bus through a dedicated, non-load serving feeder

___ MVA

R-DER Modeling Gross aggregate nameplate rating of all connected R-DER resources that offset customer load including residential, commercial, and industrial customers

___ MVA


Preface

• Step 1 – Guideline on Modeling DER in Dynamic Load Models Set framework for modeling DER in powerflow and dynamics Differentiated between U-DER and R-DER Adaptable to utility needs Approved by PC in 2016 (reopened comment period…)

• Step 2 – Guideline on DER Modeling “I know how to differentiate and where to put the DER in the model…” “…but what actual models and model parameters do I use?”


Topics of Guideline

DER Dynamic Load Modeling Framework (revisit)DER Modeling Practices and Model Parameters Data collection Synchronous DER models 2nd generation renewable energy system modelso Solar PV modelingo Battery energy storage system modeling

PV1 Model PVD1 Model DER_A Model

U-DER and R-DER Modeling Capabilities


Data Collection

For the purposes of modeling:U-DER Type of generating resource (e.g., recip engine, wind, solar PV, BESS) Distribution bus nominal voltage where the U-DER is connected Feeder characteristics for connecting U-DER, if applicable Capacity of each U-DER resource (Pmax, Qmax) Control modes – voltage, frequency, active-reactive power priority

R-DER Aggregate capacity (Pmax, Qmax) of R-DER for each feeder or load as

represented in the powerflow base case Vintage of IEEE 1547 (e.g., -2003) (or other relevant standard reqs.) As available, aggregate information characterizing the distribution circuits

where R-DER are connected


Synchronous DER Models

Recommendations: Use gentpj model with Kis = 0 (same representation as gentpf, requires

same list of parameters as genrou) If modeling information available, use that data. Otherwise, use

engineering judgment to develop reasonable parameters based on type of synchronous DER.

Examples of synchronous DER modeling parameters are provided for situations where no detailed information is provided.


2nd Generation Renewable Energy System Models

Recommendations: Detailed models, but the complexity of these models is often not necessary

for interconnection-wide modeling. Other models may be more suitable and easier to use for representing DER.

These models may be of value in certain situations – detailed interconnection system impact studies, large capacity resources relative to local interconnecting network, or other special studies

TPs and PCs should determine the appropriate situations where these complex models are useful for modeling DER to study the dynamic behavior of the BPS.

Example sets of models and model parameters for solar PV and BESS provided


PV1 Model

Recommendations: Created as temporary solution for BPS-connected solar PV prior to 2nd

generation models being developed. Not implemented consistently across software platforms. Therefore, use of

the PV1 model is not recommended. For detailed solar PV modeling, the 2nd generation renewable models are

recommended. For aggregated representation of DER, including solar PV, the PVD1 and

future DER_A models are best suited.


PVD1 Model

Recommendations: Most flexible, easy to use, and appropriate model for representing

aggregate solar DER such as R-DER. Reasonable representation for U-DER, particularly when detailed

information related to specific equipment and controls not available. However, may not be adequate for detailed system studies with very high

DER penetration levels in certain regions or other special studies.


DER_A Model

Upcoming model – being implemented now by simulation toolsSimplified version of 2nd generation renewables model(s)Parameter list size similar to PVD1 (relatively small)Additional features to PVD1 Frequency controls Voltage controls Power factor and reactive power controls Inverter cutouts for aggregated response Fractional re-energization Ramp rate limits

Recommendation: Use this model once implemented and benchmarked Modeling Notification likely to follow


U-DER Capabilities

Table 3.1: U-DER Modeling Options BPS Model Options

Model PSLF PSSE PW PT V&R

Synchronous Machine Models X X X X X

2nd Generation Renewable Models X X X X X

PV1 X X X X1 -

PVD1 X - X - -

DER_A2 - - - - -


R-DER Capabilities

Table 3.2: R-DER Modeling Capability

Criteria Modularized

Approach DER in CLM DER Model in CLM

GE PSLF cmpldw21 cmpldwg Simplified version of PVD1

PTI PSSE No None None

PowerWorld Simulator Yes DER can be used in

conjunction with any load model, including CMPLDW

DGPV (simplified version of PVD1)

PowerTech TSAT No None None

V&R Energy POM No None None

Recommendation to software vendors: Implement DER_A model into CLM once ready Continue modularized approach for benefit of load and DER modeling


Approval

LMTF/SAMS is seeking approval to post the guideline for 45-day industry comment period

LMTF/SAMS will respond to industry comment and bring back final draft at the September 2017 PC meeting (or soon after)


Plant-level Control and Protection Modeling Task Force ReportPC Final Approval

Mohamed Osman, P.E., Senior Engineer of System AnalysisPC MeetingJune 6-7, 2017


PCPMTF Background

• PCPMTF: Plant-Level Controls and Protection Modeling Task Force Studying effects of plant-level, turbine, and boiler control and protection

systems Comprehensive look at the short- and mid-term post-disturbance behavior of

plant control and protection systems Outlining impacts plant control and protection systems have on unit reliability

and system stability during grid disturbances

• PCPMTF Stakeholders: Turbine Manufacturers; Generators Owners/Operators; North American

Generator Forum (NAGF); experts in power system dynamics and control; stability simulation software vendors


Report Overview

• Report Covers: Events Involving Turbine and Boiler Controls Recommendation 21: Acceleration Control Function Potential New Models for Use in Dynamic Simulations Turbine-Governor Models with Representation of Plant-level DCS

Controls


Task Force Recommendations

• Adopt a model similar to gp1 (and gp2) in GE PSLFTM that can monitor and provide warnings of potential unit tripping due to the generator encroaching on possible trip-zones of protection systems.

• Inclusion of Volt/Hz, over excitation limiter, under excitation limiter and reverse power dynamic models in future year planning cases.

• NERC SPCS should look closely at the reliability impacts of plant-level controls and protection on applicable NERC Reliability Standards.


Approval Item

• Presented to the PC March 2017 for industry comments• No comments received by industry• No substantial revisions to report• PCPMTF is requesting final PC approval for the Plant-level

Control and Protection Modeling Task Force Report


Integrating VER into Weak Power SystemsReliability Guideline Approval for Industry Comment

Ryan D. Quint (NERC), Jason MacDowell (GE)NERC Planning Committee MeetingJune 6-7, 2017


• Identified by NERC Staff, SAMS leadership, and NERC staff as high priority topic of interest

• Coordination with CIGRE WG 4.62 leadership and US representatives

• Goals Proactive vs. reactive North American industry awareness Consolidate and share key takeaways from CIGRE Technical Brochure 671 –

“what does the utility industry NEED to know today?”

• Coordinated “fast-track” activity by CIGRE WG B4.62 leadership Subject matter expertise SAMS members NERC staff

So Why?


• Increasing penetration of variable energy resources (VER)• “Weak” grid conditions• Assessment of system strength• Short circuit ration (SCR) & SCR-based metrics• Issues resulting from weak grids• Planning considerations• Solution strategies

Overview of Reliability Guideline


Increasing Penetration of VER


“Weak” Parts of the Power System

Source: NREL/GE


• System strength is relative• “Weak” is system specific Transmission topology Neighboring resources

• “Weak” is application/equipment specific Capacity/output of plant Types of controls implemented

System Strength Fundamentals


• Short circuit ratio (SCR)• SCR-based metrics Weighted short circuit ratio (WSCR) Composite short circuit ratio (CSCR) SCR with interaction factors (SCRIF)

• MV vs. MVA Application• Should be used at a high level• No uniform “threshold” value for defining “low”• Useful tool(s) to identify potential weak grid issues• Used to instigate more detailed studies (EMT-type)

Quantifying Weak Grids

𝐶𝐶𝐶𝐶𝐶𝐶𝐶𝐶 =𝐶𝐶𝐶𝐶𝐶𝐶𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑉𝑉𝑉𝑉

𝐶𝐶𝐶𝐶𝐶𝐶𝑃𝑃𝑃𝑃𝑃𝑃 =𝐶𝐶𝐶𝐶𝑀𝑀𝑆𝑆𝑆𝑆𝑃𝑃𝑃𝑃𝑃𝑃𝑀𝑀𝑀𝑀𝑀𝑀𝑉𝑉𝑉𝑉

𝑀𝑀𝐶𝐶𝐶𝐶𝐶𝐶 =∑𝑖𝑖𝑁𝑁 𝐶𝐶𝐶𝐶𝑀𝑀𝑆𝑆𝑆𝑆𝑖𝑖 ∗ 𝑃𝑃𝑉𝑉𝑀𝑀𝑅𝑅𝑖𝑖

∑𝑖𝑖𝑁𝑁 𝑃𝑃𝑉𝑉𝑀𝑀𝑅𝑅𝑖𝑖

2

𝐶𝐶𝐶𝐶𝐶𝐶𝑆𝑆𝑆𝑆𝑖𝑖 =𝐶𝐶𝑖𝑖

𝑃𝑃𝑖𝑖 + ∑𝑗𝑗 𝑆𝑆𝑆𝑆𝑗𝑗𝑖𝑖 ∗ 𝑃𝑃𝑗𝑗


• Should be used at a high level• No uniform “threshold” value for defining “low”• Useful tool(s) to identify potential weak grid issues• Used to instigate more detailed studies (EMT-type)• Each metric has pros and cons – should be understood

Applying Any SCR-Based Metrics


Quantifying Weak Grids


• Manufacturer Involvement• Classical Voltage Stability in Weak Grids• Control Interactions• Control Instability• Disturbance Ride-Through Capability• Phase lock loop stability

Weak Grid Issues


• Transient Stability Limitations Validity for phenomena slower than 5 Hz Positive sequence based RMS based Large simulation time step Convergence issues Limited converter electrical representation

• Electromagnetic Transient (EMT) Type Models• Study Model Requirements Generic Detailed EMT, as applicable

Planning Study Considerations


• Synchronous Condenser• Plant Control Changes• Converter Control Changes• Reduction in Plant Capacity or Power Output• Transmission Reinforcement• FACTS Devices

Potential Solution Options


• High penetration of wind in ERCOT West Texas• Synchronous condenser and wind farm interactions in ISO-NE• Classical weak grid voltage stability in BPA• Transformer energization issues in Southern Company

Industry Examples


• SAMS is seeking approval to post guideline for 45-day industry comment period

• Planned final approval following comment period either in September 2017 (or shortly thereafter) based on comment received

PC Action


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