Oscillation Monitoring System Mani V. Venkatasubramanian Washington State University Pullman WA
Oscillation Monitoring System IEEE C37.118 Real-time PMU data stream TCP or UDP OpenPDC OMS SQL server OMS results txt file OMS action adapter built into OpenPDC 64 bit version 1.4 sp1. Available for beta testing. 2
Start OMS Flowchart Read data from PDC Event? Yes Damping Monitor Engine No FDD analysis for ambient data Prony analysis for postdisturbance data Event Analysis Engine Moving window crosscheck Moving window crosscheck Poorly damped mode detected? Yes Alarm Controller trigger No 3
Complementary Engines Event Analysis Engine Three algorithms: Prony, Matrix Pencil and Hankel Total Least Square. Aimed at events resulting in sudden changes in damping Damping Monitor Engine Ambient noise based. Continuous. Frequency Domain Decomposition Provides early warning on poorly damped modes 4
Voltage (V) 5.15 x 10 5 Results from Two Engines Bus Voltage Magnitude at Cumberland 5.14 5.13 5.12 5.11 5.1 Event Analysis Ambient Noise Analysis 1.2 Hz at +1.8% damping. Local Mode. 5.09 1.2 Hz at +1.5% damping. Local Mode. 820 840 860 880 900 920 940 Time (s) Nov. 29th 2007 TVA event 5
Event Monitor Engine OMS Engines Automated Prony type analysis of oscillatory ringdown responses Ten seconds of PMU data analyzed every one second Damping Monitor Engine Automated analysis of ambient noise data Five minutes of PMU data analyzed every ten seconds Multiple PMUs Fast and Accurate 6
WECC Project CERTS/DOE Projects Evaluation of OMS tools using MiniWECC and PSLF simulation data and WECC archived data. Entergy Project Implementation of OMS tools for analyzing Entergy PMUs. Damping Monitor Engine: 5 minute data length, 10 second refresh time, 30+ PMUs. Excellent feedback from operations: New developments: Estimation confidence measures, Mode Energy measures, Novel displays (STI). 7
FY12 Technical Progress Damping Monitor Engine Four minute and two minute engines developed and tested Efficient post-processing algorithms developed Real-time engine implemented in WECC test server since November 2011 Event Analysis Engine Real-time version updated to openpdc 1.4 sp1 Handles 37.118 streaming PMU data Outputs to SQL server database 8
FY12 Technical Objectives WECC system and Entergy system Design and Testing of Damping Monitor Engine for shorter data lengths Design and Testing of Event Analysis Engine for handling complex events Portability and Cybersecurity of algorithms Engineer friendly and operator friendly Robust algorithms towards data quality issues Develop off-line versions for engineers 9
FY12 Technical Work Damping Monitor Engine Field demonstration of real-time engine at Entergy Off-line engine prototype for WECC Event Analysis Engine Field demonstration of real-time engine at Entergy Off-line engine prototype for WECC 10
FY12 Risk Factors Data quality issues Different PMU vendors Computational burden OpenPDC updates Validation of results 11
FY13 Technical Work WECC system and Entergy system Extend engines to handle hundreds of PMU data in real-time by efficient multithreading Robust algorithms for addressing data quality issues Improve Damping Monitor Engine by running multiple tasks while using shorter data lengths Improve Event Analysis Engine for handling complex events among multiple processors Develop off-line versions for engineers 12
Back-up slides 13
Damping Monitor Estimation Results Dominant modes are analyzed for each data set (every ten seconds) For each mode: Mode frequency Mode damping ratio Mode energy Mode shape Estimation summary flag Estimation confidence level 14
Confidence level, % Mode Energy Damping Ratio / % Frequency / Hz 0.36 Western Data Analysis Case BPA 08-31-2010 2sec Refresh Estimation Results for Mode @ 0.34 Hz with 0.5 min averaging 0.34 0.32 0.3 0 50 100 150 200 250 Time / minutes, Ave.= 0.33293 Hz, Std.= 0.0093104 Hz Mode Frequency 15 10 5 0 0 50 100 150 200 250 Time / minutes, Ave.= 8.2511 %, Std.= 2.2856 % Damping Ratio 60 40 20 0 0 50 100 150 200 250 Time / minutes, Ave.= 15.8168, Std.= 10.6515 Energy Estimate 100 95 90 85 Estimate Confidence 80 0 50 100 150 200 250 Time / minutes, Ave.= 0.89863, Std.= 0.040025 15
Damping Ratio / % Fr 0.3Rapid Changes in System Damping 0 50 100 150 200 250 15 Time / minutes, Ave.= 0.33293 Hz, Std.= 0.0093104 Hz Western System Event 10 5 0 0 50 100 150 200 250 Time / minutes, Ave.= 8.2511 %, Std.= Time 2.2856 (minutes) % 16
MALN_Malin_Bus_Voltage_VMag Rules for Real-time Prony Analysis MALN_Malin_Bus_Voltage_VMag vs time 550 548 546 544 542 540 538 536 534 60 80 100 120 140 160 180 Time (s) Three types of Consistency Crosscheck rules Different Curve-fitting Methods (Redundancy) Different Signal Groups (Superposition) Moving Window Analysis (Linearity of Reponses) 17 17
Event Analysis Engine Start Read data from PDC and data clean-up Event detection Local PMU Analysis and Crosscheck Local PMU Analysis and Crosscheck Local PMU Analysis Inter-area Mode Analysis and Crosscheck Inter-area Mode Analysis Display 18 18
Event Analysis Example Eastern System Event Local oscillations at a generating plant 1.18 Hz oscillations 19 19
Case Study 1 Local PMU Analysis PMU5 PMU6 20
Case Study 1 Multiple PMU Analysis Consistent estimate at 352 sec Oscillation frequency = 1.18 Hz Mean damping ratio = 0.09% 21
Case Study 2 Western event PMU Bus Voltage 2.5 0 Event Analysis Damping Estimate -2 22