Western Electricity Coordinating Council
Joint Synchronized Information Subcommittee
2011 – 2015Workplan
DRAFT FOR DISCUSSION
September 26, 2011
WECC utilities and RCs are involved in wide-scale deployment of phasor measurement units and their applications under the Smart Grid Investment Grant (SGIG) projects. WECC Joint Synchronized Information Subcommittee (JSIS) is taking steps to align its workplan with the needs of the SGIG projects to fully utilize the benefits of the investments.
WECC JSIS focus areas include:
- Analysis of power system dynamic performance (on-going activity by operating entities)
- Event analysis and system performance evaluation
- Power plant performance analysis and model validation
- Lesson’s learned papers
- Analysis and studies to support the development of operating procedures
- Operator training materials
- Analysis and studies to support the development of synchro-phasor based controls
- Engineering applications of synchro-phasor data
- Data mining and event detection tools
- Power system dynamic performance baselining
- Model validation tools
- PMU placement guidelines
- Wide-area situational awareness applications
- Oscillation Detection application
- Mode Meter application
- Voltage stability applications
- Synchro-phasor data conditioning and verification.
- Synchro-phasor technology
- Handbook “Introduction to Synchro-phasors”
- PMU performance requirements and inter-operability
- Synchro-phasor network communication standards
- Synchro-phasor network security, availability and reliability
WECC JSIS will prioritize the activities and will work with NERC NASPI and DOE on the resource plan to adequately support the critical activities.
- Analysis of Power System Operations (under development)
A)Event Analysis
Coordinate with
-WECC OC / Performance WG
WECC JSIS will conduct event analysis as such need develops, and will support event analysis teams in WECC and NERC.
WECC JSIS will use the synchro-phasor data to maintain the frequency response baseline in the Western Interconnection:
-Interconnection frequency response at nadir
-Interconnection frequency response at the settling frequency, settling time
-Interconnection frequency response at 20, 30, 60, 90 seconds
-Power pick-up on major transmission paths
WECC JSIS will perform correlation analysis between the frequency response performance and power system conditions (loading, generation mix, transfers, etc).
WECC JSIS will use the synchro-phasor data to maintain the oscillation baseline in the Western Interconnection.
WECC JSIS will support the development of the lesson’s learned paper by WECC.
B)Power Plant Performance Analysis
Coordinate with
-WECC Control WG
-WECC Model Validation WG
WECC JSIS will work with WECC MVWG to distribute, support and provide training on the Power Plant Model Validation (PPMV) application. WECC JSIS will use PPMV application to produce reports of power plant performances during system events.
WECC JSIS will work with Control WG to develop “benchmark” performances for each type of generators and will compare the actual/modeled plant performance versus the benchmark.
C)Lesson’s Learned Papers
WECC JSIS will support the development of the lesson’s learned paper by WECC and NERC.
D)Operating Procedures
WECC JSIS will support the development of the operating procedures that use synchronized wide-area information, including:
-Review study plans
-Review and conduct studies when requested
-Review actual operating data
-Review operating procedures
-Recommend alarm levels and settings
The operating procedures will apply to:
-Phase angle alarms
-Mode meter application
-Oscillation detection application
E)Training Materials
WECC JSIS will help with the development of training materials for system operators on using the Wide-Area Situational Awareness applications
F)Wide-Area Control Schemes
WECC JSIS will review the development of the wide-area control schemes that use synchronized wide-area information, including:
-Review study plans
-Review and conduct studies when requested
-Review actual operating data
- Engineering Applications
A)Data Mining and Event Detection Tools
Coordinate with
-WECC OC / Performance WG
-NERC NASPI Planning Implementation Task Team
Vickie VanZandt summarized it well: “We are data rich, information poor.”WISP data will generate tens of TBs of data every year. There is a need for automatic screeningof the data for disturbances or unusual system conditions.
Objectives / Tasks2a. Develop “an engineering tool” that automatically detects grid disturbances and unusual operating conditions / Task 2a:
Develop and implement an “engineering tool” that detects grid disturbances and unusual system conditions such as:
-system events
- network faults and line outages
- off-nominal frequency events
- fault-induced delayed voltage recovery events
- forced oscillations
- frequency response
- voltage controls
- power system stabilizers
B)Power System Dynamic Performance Baselining
Coordinate with
-WECC OC / Performance WG
-NERC NASPI Planning Implementation Task Team
Baseline (noun) is a self-consistent set of measurements and performance metrics that can be used as a reference for the evaluation of future observed and anticipated conditions.
Baselining (verb) is comparing the data characterizing some condition of interest with an appropriately chosen of baseline measurements. Baselining involves two processes (a) getting and archiving the baseline and (b) using the baseline.
Getting and archiving the baseline:
•Record system measurements that best indicative of system stress:
–Total generation in an interconnection
•Percent of dispatchable load-following generation
•Percent of variable energy resource generation
–Phasor angles
–Generation clusters
–Power flows on key flowgates
–Reactive power reserves, etc
–Status of critical lines and flowgates
–Status of critical generators
–Simultaneous phasor angles andpower flows on different interfaces (especially bringing power to the same sink)
•Calculate dynamic performance indicators:
–Frequency response performance (pre-disturbance, dip and settling frequency, time of minimum dip, size of generation event, etc)
–Oscillation performance (frequency, damping, energy, mode shapes)
–Voltage stability and power-angle indicators
•Correlate dynamic performance indicators with measurements
Using the baseline:
•Tracking system performance over time
•Detecting and acting upon acute changes in the system performance
•Comparing observed dynamic performance against the models
Baselining to be done at various levels:
•Interconnection
–Control area (Balancing Authority / Transmission Operator)
•Power Plant
Availability of a complete set of wide-coverage synchro-phasor data sets is a pre-requisite for all tasks below.
Objectives / Tasks2B-1 Develop and maintain seasonal baselines for phasor angles in an interconnection / Task 2B-1a:
Record phasor angles and develop norms for each operating season / day of week / on- and off-peak.
Task 2B-1b:
Record phasor angles from seasonal and week ahead SOL studies. Compare the angles with the norms established during the baseline. Determine if phasor angles can be used to back up operating nomograms.
2B-2. Develop and maintain a frequency response baseline for Western Interconnection / Task 2B-2a:
For each qualified system frequency event, record the following:
- Disturbance size
- include event details (generator breaker trip vs. turbine trip, simultaneous vs. staggered trip, other actions such as dynamic braking or load shedding during the event)
- Pre-disturbance frequency, system frequency dip, and settling frequency
- save system frequency profile
- On-line generation and generation capacity
- amount of synchronous generation
- amount of non-synchronous generation
Task 2B-2b:
Compare observed system frequency performance with that produced by simulation models and advise modeling work group.
2B-3. Develop and maintain a baseline for inter-area power oscillations in Western Interconnection / Task 2B-3a:
Based on system studies, identify critical factors that affect inter-area oscillations, such as:
- Status of critical lines
- Phasor angle separation across the system
- Flows on major flowgates
- Status and generation levels of generation injections groups
- Reactive support, etc
Continuously calculate and archive the following quantities from wide-area PMU data:
- Inter-area oscillation modes, including their frequency, estimated damping, energy, and mode shapes
Task 2B-3c:
Compare observed oscillatory performance with the behavior observed by power system models and advise modeling work group.
C)Power System Model Validation Tools
Coordinate with:
-WECC TSS / Modeling and Validation WG
-NERC NASPI Planning Implementation Task Team
Decisions on power system operating limits are based on power system studies. The studies rely on the accuracy of power system models in predicting system performance for anticipated disturbances. Periodic system model validation is necessary to ensure that the power system models are accurate and up to date. Actual disturbances present great opportunities for model verification and model improvements. The need for a continual system model validation is recognized in a white paper prepared by NERC Model Validation Task Force under Transmission Issues Subcommittee in May 2010. The need for generating unit model validation is addressed by NERC MOD-026-27 standards.
Model validation needs to be performed at various levels:
•Interconnection
–Power Plant
–Load center
–Grid controllers like HVDC, SVC, etc
Objectives / Tasks2C-1. Support WECC MVWG in developing tools and conducting regular power plant model verification studies using disturbance data / Task 2C-1a:
Develop a lesson’s learned paper on using PMUs for power plant model validation.
Task 2C-1b:
Develop requirements for the grid simulatorsto have disturbance playback capabilities in their software packages
Task 2C-1c: develop automated tools that use disturbance recordings for power plant model verification
Task 2C-1d: develop processes and tools for managing data, both model data and disturbance records, for power plant model validation
Task 2C-1e: develop understanding of the sensitivities of power plant data and controls with respect to observed dynamic performance
Task 2C-1f: apply similar methods for validation of load models and grid controllers
Task 2C-1g: provide training for use of the tools for power plant model verification
2C-2.Support WECC MVWG in conducting regular system-wide model verification studies using disturbance data / Task 2C-2a: put in place systems for disturbance data collection and for system performance analysis
Task 2C-2b: develop understanding of the sensitivities of system model data with respect to observed dynamic phenomena
Task 2C-2c: continue developing tools for system-wide model validation
D)PMU Placement Criteria
Coordinate with:
-WECC TSS / Modeling and Validation WG
-NERC NASPI Planning Implementation Task Team
Objectives / Tasks3D-1. Review and revise WECC PMU placement guideline / Task 3D-1a:
Maintain and review WECC PMU Placement Guideline
Task 3D-1b:
Identify substations and signals that are needed for reliability applications
3D-2. Support the development of NERC disturbance monitoring standards / Task 3D-2a: Review, comment and support the development of NERC disturbance monitoring standards
- Wide-Area Situational Awareness Applications
Coordinate with:
-WECC OC
-NERC NASPI Operations Implementation Task Team
A)Oscillation Detection Application
Detection of power oscillations is one of the premier applications of the synchro-phasor technology. There is variety of power oscillations in the system, including:
-inter-area electromechanical power oscillations – energy exchanges between large groups of generators, usually at 0.2 to 0.7 Hz frequencies in the WECC today (e.g. COI power oscillations on August 10, 1996 and August 4, 2000)
-local electromechanical oscillations – a generator is oscillating against the interconnection, usually at 0.7 to 1.5 Hz frequencies (Boundary oscillation)
-control oscillations (PDCI oscillation in January 2008)
-generator torsional oscillations
Usually, the oscillations are limited in the magnitude. The problem is when the oscillations are growing or sustained at high amplitude. Growing or large oscillations often result from high system stress, failed/malfunctioning controllers or a resonance condition. There is a need for an operational application to alarm dispatchers when an oscillation represents stability risk. Oscillation Detection application would scan dozens of signals over a wide frequency range for any signs of growing or large oscillations.
Objectives / Tasks3A-1. Support development, deployment, testing and performance evaluation of Oscillation Detection applications / Task 3A-1a:
Develop performance requirements for Oscillation Detection application
Task 3A-1b:
Review capabilities of the available Oscillation Detection applications
Task 3A-1c:
Develop test procedures and back-test the Oscillation Detection applications using historic data
Task 3A-1d: review / recommend settings for Oscillation Detection applications
Task 3A-1e: review performance of Oscillation Detection applications
B)Mode Meter Application
Oscillation Detection application described above is “reactive”, it indicates a problem after an oscillation is developed. The value of the Oscillation Detection application is that it catches all oscillations up to 30 Hz, including those cause by controller malfunctioning or failure.
Mode Meter is “predictive.” It estimates damping of power oscillations from ambient “noise” data. Mode Meter, however, applies only to specific modes of the inter-area power oscillations.
Objectives / Tasks3B-1. Support deployment, testing and performance evaluation of Mode Meter applications / Task 3B-1a:
Develop/review performance requirements for Mode Meter application
Task 3B-1b:
Review capabilities of the available Mode Meter applications
Task 3B-1c:
Develop test procedures and back-test the Mode Meter applications using historic and simulated data
Task 3B-1d: review / recommend settings for Mode Meter application
Task 3B-1e: review performance of Mode Meter application
Task 3B-1g: perform correlation analysis between Mode Meter estimates and the power system conditions
C)Voltage Stability Application
Many transmission paths are voltage stability limited in the West. While there has been significant amount of research done in developing voltage instability indicators, there is a need to test and validate them in the production environment.
Objectives / Tasks3A-1. Support development, deployment, testing and performance evaluation of Voltage Stability applications / Task 3A-1a:
Review available Voltage Stability applications for dispatcher situational awareness. Determine the course of actions, work with DOE and EPRI in framing the research agenda
D)Synchro-phasor Data Conditioning and Validation
A production-grade synchro-phasor network is designed to the highest levels of reliability and cyber security. Yet, the critical real time applications must be designed to tolerate data dropouts and glitches, and must be capable of recognize corrupted data. A higher-level data validation is required.
Objectives / Tasks3E-1. Develop methods for on-line validation of synchro-phasor data / Task 3E-1a:
Request NASPI Research Task Team to provide guidance on methods that can be used for synchro-phasor data validation. These should include data glitches, data dropouts, CT-PT failures, stale data, loss of synchronization, intrusion in the data system, etc.
- Synchro-phasor Technology
A)Synchro-phasor Handbook
Coordinate with
-NERC NASPI
Several utilities have asked for a PMU Handbook. The most common questions are related to the There is a need for a common place to answer the
-Why should a utility install a PMU? What does a company get out of installing a PMU? (This is asking more for a cost-benefit analysis/justification.)
-How much does it cost ? - device, telecom, control center work, are there any end-to-end solution providers?
-Does it have to be CIP compliant ?
-Can I upgrade my relays to PMU functionality? Does it have CIP implications?
-What PMU data can be used for ? Where can I get the apps ?
-Where can I get help with a business case ?
-What is the cost comparison between installing a PMU vs a DFR? For the unit itself, other associated equipment, and typical overall cost (including labor).
-What are the advantages/disadvantages or pros/cons for installing a PMU vs DFR?
-Where should a PMU be installed? At generation sites? At transmission substations? At what voltage levels?
-What does it take to install a PMU? In addition to the PMU unit, what other equipment needs to be installed to make a PMU functional?
-What data are we looking for? What data to record? How much data storage would be needed?
-Does the PMU data need to be streamed to the control center?
-What are the pros and cons for using a separate PMU unit vs the PMU functionality in existing relays?
-Is it still worthwhile to install a PMU if there are not enough internal resources to analyze the data?
-How do you install a PMU?
B)PMU Performance Requirements and Interoperability
Coordinate with
-IEEE
-NASPI Performance and Standards Task Team
WECC JSIS will provide input to IEEE and NASPI on PMU dynamic performance requirements.
C)Synchro-phasors Data Network Standards
Coordinate with
-IEEE
-NASPI Performance and Standards Task Team
WECC JSIS will provide input to IEEE and NASPI on PMU dynamic performance requirements.
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