# Security Analysis

PowerWorld Corporation provides software training in the use of PowerWorld Simulator and add-on products OPF, SCOPF, OPF Reserves, ATC, PVQV, Transient Stability, and SimAuto. Our training also covers some basics of the engineering, operations, and economics of interconnected power systems.

Slides used in the 2-day course, Steady-State Power System Security Analysis with PowerWorld Simulator, are available here. If you don’t yet have PowerWorld Simulator you can perform many of the exercises covered in these training modules on our free 13-bus evaluation version.

## Topics

### S1: Power System Modeling

Nominal Voltage Levels and Per Unit; Admittance and Impedance; Y-Bus Matrix; Buses, Branches, Loads, Switched Shunts, and Generators; Power Flow Equations; PV, PQ, and Slack Buses; Newton’s Method; Multiple Solutions; Example 2-Bus Power Flow; PV and QV Curves; Maximum Loadability

### S2: Advanced Power Flow Solution Options

Detailed Overview of Simulator’s Single Solution; Pre-Processing; Angle Smoothing,; Remote Regulation Viability; Estimate MW Change; MW Control; Voltage Control; Generator Mvar Limit Checking; DC Line Solution; Switched Shunt Control; Transformer Switching; Transformer Stepping Methodology; Inner Power Flow Loop; Message Log Colors; Advanced Power Flow Options; Dynamically assign slack buses; Power Power Flow Solution Actions; Minimum Per Unit Voltage for Constant Power and Constant Current Loads; Parallel LTC Tap Balancing; Minimum Sensitivity for LTC Control; Generator Mvar Sharing for Remote and Local Generation; Switched Shunt switching in inner power flow loop; Transformer Regulation Target Type; Area Control with Multiple Islands; Power Flow Solution Diagnosis Aids

### S3: Getting a Case to Solve (slides only)

Very Low Impedance Branches; Voltage Control Devices (Transformers, Switched Shunts, etc…); Area Generation Control (AGC) and Area Control Error (ACE); Clear Transactions and auto-insert tie-line transactions; Using Generator Mvar Limits “Check Immediately” option; Voltage Collapse visualization and Solution; Negative dV/dQ interpretation; Robust Solution Process

Advanced Limit Monitoring; Monitoring Exceptions; Contingency Blocks; Contingency Global Actions; Conditional Contingency Actions; Modeling Remedial Action Schemes (RAS) or Special Protection Schemes (SPS); Model Conditions; Model Filters; Model Expressions; Contingency Element Status; Advanced Contingency Options; Bus Load Throwover Records; Generator Maximum MW Response; Generator Post-Contingency AGC; Generator Line-Drop or Reactive Current Compensation; Post Contingency Auxiliary Files; Sample Case; Design and Simulate a Special Protection Scheme (SPS); TLR Analysis; Line Loading Replicator; OPF with minimum control change; Using Combined Tables for Reporting; Report Writing; Comparing two sets of Contingency Results; Other Actions

### S5: Available Transfer Capability (ATC) (slides only)

Input and Output of an ATC Calculation; What does the ATC Calculation do?; ATC Dialog Options; Solving the ATC in Simulator; Explanation of Results; Recommendation for Better/Faster Analysis; Alternative Advanced Solution Techniques; Extra Monitors and Multiple Scenarios
Supplement: Linear Analysis Techniques in PowerWorld Simulator

### S6: Voltage Stability Using PV Curves (slides only)

Voltage Stability Concepts and Studies; What are PV Curves?; PV Curve Results; Injection Groups; Participation Points; Contingency Definition; PV Curve Study; Setup; Quantities to Track; Limit Violations; PV Output; PV Results

### S7: Voltage Stability Using QV Curves (slides only)

What are QV Curves? ; How is a QV Curve performed?; Example QV Curve; QV Curve with Mvar Deficiency; V-Q Sensitivities; QV Curve Study; Contingency Definition; Buses, Options; Control/Results

### S8: Security Analysis for a Generator Interconnection Study (slides only)

Example Comparing Two Sets of Contingency Results; Adding a new Generator; Setting up a list of Contingencies and Options; Running Contingency and Saving Results; Build Comparison Case with a transfer of power from new generator; Comparing the two sets of Contingency Results; Running ATC Study on the new generator; Automating the ATC run using auxiliary files; Plotting QV Curves for near the new generator; Comparison of Full AC Contingencies to Linearized DC solutions; PV Curve Study for transfer of power from the new generator; General Automation Techniques

### S9: ATC/PVQV Automation Examples (slides only)

Nominal Voltage Levels and Per Unit; Admittance and Impedance; Y-Bus Matrix; Buses, Branches, Loads, Switched Shunts, and Generators; Power Flow Equations; PV, PQ, and Slack Buses; Newton’s Method; Multiple Solutions; Example 2-Bus Power Flow; PV and QV Curves; Maximum Loadability

### S10: Integrated Topology Processing (slides only)

Introduction; Motivation; Modeling; Exploring the Case; Full-Topology vs. Consolidated Superbus; Algorithm; Topology Processing Dialog; Sensitivity Analysis; Contingency Analysis; Options; Incremental Topology Processing; “Open with Breakers” Action; Saving the Consolidated Case; Script Commands

### S11: Distributed Computing (slides only)

Outline; Motivation; Implementation; Distributable Calculations; Configuration; Single Multi‐Core Computer; Contingency Analysis; Distributed Computer Fields; IT Concerns; Benefits; Benchmarks

### S12: Geomagnetically Induced Current (slides only)

Overview; GIC Modeling; Inputs; GMD Storm Scenarios; GIC Outputs and Results; Four-Bus Example; Simulator Assumptions; Uniform Field Modeling; Time-Varying Inputs; Large Model Example; Sensitivity Analysis; Neutral Blocking