1 Application of Synchrophasor Technology To CREZ System CREZ Technical Conference January 26, 2010 Navin Bhatt American Electric Power

2 Outline 1.Synchrophasor Technology 2.Potential Applications 3.Applications to Consider for CREZ System

3 1. Synchrophasor Technology Phasor: An electrical quantity with magnitude and phase (angle) Synchrophasors: Time-synchronized phasors

4 Phasor Representation Courtesy: CERTS/EPG

5 Courtesy: Eastern Interconnection Phasor Project (EIPP) Synchrophasor Infrastructure

6 SCADA Data Vs. Synchrophasors SCADA – Conventional Situational Awareness Technology Advantages of Synchrophasor Technology Direct measurement (as opposed to calculated values using model-based SE solutions from SCADA data) 8/14/03 Blackout: AEP SE could not converge; PMU data kept coming Time-stamped data, accurate within tens of micro-seconds of UTC High resolution (10-60 samples per second)

7 Technology Promise Synchrophasor Technology Can provide situational awareness on a sub-second basis over wide area Instantaneous measure of power system stress between wide area locations Instantaneous measure of power system dynamics at given location MRI of power system vs. X-Ray by SCADA technology PMU data well suited to activate automated controls

8 AEP Synchrophasor Project AEP/Texas –AEP is taking a leading role in DOE/ERCOT efforts to install synchrophasors in ERCOT –AEP was the first utility in ERCOT to install PMUs Provide real-time data feed to ERCOT –Work in progress to display modal analysis results in AEP Transmission Operations AEP/East –Synchrophasor infrastructure includes 25 PMUs

9 2. Potential Applications Industry Challenge: Research, Develop and Deploy Applications –Develop Practical Data Tools for Operators –Do NOT need more PMU data –Need Actionable Information

10 2. Potential Applications Industry Resources –Opportunities to Learn & Get Involved –North American Synchrophasor Initiative (NASPI) ( –NERC Real-Time Application of PMUs to Improve Reliability (RAPIR) Task Force –IEEE

11 NASPI

12 NASPI

13 IEEE

14 3. Applications for CREZ System Large Penetration of Wind Generation Opportunity –To provide leadership in the DOE “20% by 2030” vision –To show it can be done! Challenges –Lower overall system inertia –Altered frequency response –Altered small signal stability performance –Energy balance requirements due to generation variability. Can we take advantage of synchrophasor technology?

15 Using PMUs for Renewable Resource Integration Wind Farm connected to AEP’s Ajo Station PMU data from AEP stations (including Ajo) in ERCOT Control Center PMU Data to Control Center The ‘Last Mile’ is bringing the PMU data into the Control Center for Wide Area Monitoring and Control

16 3. Applications for CREZ System Potential Applications to Consider –Visualization –Small Signal Stability Performance –Model Validation –Voltage Stability Performance –Advanced Automated Controls –……..

17 3. Applications for CREZ System Visualization –RTDMS already deployed at ERCOT –PMU Data Display: Added Value? –Information (Requires R&D) Acceptable ranges of quantities displayed Alarms Corrective actions to take

18 3. Applications for CREZ System Small Signal Stability Performance –Modal Analysis (Dominant Frequencies & Associated Damping) –Off-Line Analysis Listen to what the system is telling you Detect Trends: Daily, Seasonal, Long Term Correlate with Levels of Wind Generation –Real Time Analysis Detect damping problems –Tools already available Take corrective actions –Will require R&D

19 3. Applications for CREZ System Validation of Dynamic Models –Need high resolution data (e.g. PMU data) –Calibrate & fine-tune simulation models by comparing simulation results with synchrophasor data –WECC Model Validation WG efforts –Opportunity to use data from PMUs at wind generation collection point (transmission buses) to validate wind generation and other dynamic models

20 3. Applications for CREZ System Voltage Stability Performance –Especially of benefit for a scenario involving fast voltage collapse –PMU data can be used to monitor performance in real time through a nomogram developed from off- line simulation studies –Tools being developed to calculate margin in real time (e.g. EPRI Measurement-Based Real Time Voltage Stability Monitoring) An extension of the classic power transfer equation:P 12 = V 1 *V 2 *Sin δ 12 /X 12

21 3. Applications for CREZ System Advanced Automated Controls –Grid operated with margin for anticipated contingencies Bodes well to maintain reliable bulk power system Introduces inefficiencies Can we rely on real time corrective controls under selected operating scenarios, instead? –Today’s controls too myopic Designed to address local abnormalities Centralized coordinated controls are rare –PMU Data High resolution & instantaneous Could be used to develop coordinated, centralized wide area controls

22 Summary –Synchrophasor technology is promising. –“Killer apps” are still in works. –R&D is needed –Demonstration to adopt / adapt an application is necessary (e.g. visualization with meaningful alarms) –We must work together to apply the technology to CREZ system –Will require R&D + Cooperation with NASPI, NERC, et al –Our efforts will pay off.

23 Questions

24 Extra Slides

25 Synchrophasor Infrastructure 1.Measurement Layer Phasor Measurement Unit (PMU) Measures voltage & current waveforms at high sampling rates Calculates voltage & current phasors, frequency and line flows Installed at substations

26 Synchrophasor Infrastructure 2. Data Collection Layer Phasor Data Concentrator (PDC) A hardware/software device Performs precise time alignment of data from multiple PMUs Usually centrally located Archives PMU data (optional) Processes and displays PMU data (optional)

27 Synchrophasor Infrastructure 3. Application Layer Local (Substation) Applications Centralized (EMS) Applications Off-Line (Planning) Applications