Online Security Assessment in Brazil J. Jardim June 2-5,2013 Software & Information Systems
Topics Brazilian System Overview DSA Characteristics Application and Cases New Developments
Brazilian System Overview
Brazilian System Overview Comparative size:
Brazilian System Overview New Grid Developments: Long Transmission lines
DSA Main Characteristics Detailed time domain simulation using variable-stepvariable-order, simultaneous solution of algebraic and differential equations Automatic report of security criteria (e.g., stability index by SIME-like method, damping by Prony analysis, transient voltages, thermal limits, etc.) Contingency analysis Security region computation (nomograms) Parallel processing (coarse and fine-grain)
DSA Software Layers GUI API IO Automation Parallel Processing Applications (PF, CPF, etc.) Coarse-grain parallelization Fine-grain parallelization
DSA/EMS Integration Utility k Utility 2 Utility 1 Comunication Network SAGE Real Time Operation Network Data From CNOS RTUs TCP-IP Communication Client - CTLO Results TCP-IP Comunictation CTLO Client Real Time Base Case Data DSA (Manager Process) Contingencies Simulation DSA Cluster (Worker Processes)
EMS User Interface
DSA Process Automation Static and dynamic contingency analysis Static and dynamic transfer limits (two generation/load areas) Static and dynamic security regions (three generation/load areas)
Two-Area Transfer Limit G1 G2 G1 G1 MAX G1 MIN G2 MIN G2 MAX G2 P 1 P 2 P load P export P loss
Security Region G2 Contingencies Binary search G1 G2 P 1 2 P P load P export P loss G3 G1 - Stability limit - Generation limit - Operating Point
DSA Applications in ONS Currently monitoring dynamic security on 13 transmission corridors (at least one nomogram per corridor) Objective is to reach 16 transmission corridors (4 by control center) by the end of 2013 Analysis of transmission bottlenecks in operational planning Fast computation of transmission constraints for unexpected network configuration and definition of operational orders
Example of Online DSA Application G1 G2 G3 Minas Gerais 500 kv São Paulo 440 KV G1 P = 8200 MW G2 P = 10700 MW G3 P = 14000 Southern Region Power Grid
Online Nomogram São Paulo 440 kv Dark red region: Inside dark green region: Yellow region: Inside bright green contour: Either insecure (unstable) or infeasible (beyond generation limit) Secure operation with no thermal limit violation Secure operation thus with at least one thermal limit violation Secure operation with no voltage limit violation
Case 1 Voltage Control Improve decision regarding switching of shunt devices
Case 2 N-3 Condition Limit due to voltage drop criterion computed on line with TDS Operating point Stability limit computed on line with TDS Limit due to voltage drop criterion calculated by planning area (T+30 hours later)
DSA Applications in Planning Optimization of resources Analysis of transmission bottlenecks Automatic check of grid code Interconnection limits and nomograms All this very quickly
Planning Nomogram São Paulo 440 kv Dark red region: Inside dark green region: Yellow region: Inside bright green contour: Either insecure (unstable) or infeasible (beyond generation limit) Secure operation with no thermal limit violation Secure operation thus with at least one thermal limit violation Secure operation with no voltage limit violation
Planning Nomogram Acre - Rondônia Dark red region: Inside dark green region: Yellow region: Inside bright green contour: Either insecure (unstable) or infeasible (beyond generation limit) Secure operation with no thermal limit violation Secure operation thus with at least one thermal limit violation Secure operation with no voltage limit violation
Next Developments in ONS Planning: Modeling of SPS Hybrid simulation with PSCAD/EMTDC Online: Integration to alarm process Remote access to security assessment, including portable devices Other: Cloud computing (being evaluated) Risk security assessment
ISA-CTEEP Online Analytical and PMU based DSA* R&D projects under development Online DSA PMU based DSA (by Universidade Federal de Santa Catarina UFSC) Online Model Validation using phasor measurements Online low damping source location Main challenges: Partial network observability Need of external equivalents Oscillation mode identification from environment data * Project sponsored by ISA-CTEEP/ANEEL
Comments & Conclusions Online DSA has been in 24/7 operation for several years Its integration to operators practices has been evolving along the years Online DSA demands good care of state estimation, measurements and model parameters For planning, DSA characteristics provides huge speed up and comprehensiveness to system analyses Integration with phasor measurements will allow more accurate and effective security assessment and control actions
Acknowledgements Dr. Luiz Claudio A. Ferreira and Dr. Carlos Alberto da S. Neto from ONS for their valuable comments and information
Online Security Assessment in Brazil Thanks! J. Jardim June 2-5,2013 Software & Information Systems