Transient Stability Analysis, Load Shedding Software

By: Etap Canada  09-12-2011
Keywords: Load Shedding, Bus Transfer

ETAP’s advanced Transient Stability analysis provides accurate power system modeling for dynamic simulation. Engineers use Transient Stability to identify critical clearing time, to model motor dynamic acceleration (including change in system frequency), to develop load shedding schedules, to perform fast bus transfer calculation limits, for the start-up of generators under normal and emergency conditions, and for calculating various system dynamics. With the ETAP Transient Stability module, you can energize/synchronize multiple isolated systems or split a system into multiple subsystems. One of the most powerful tools in the Electrical Transient Analysis Software is the ability to automatically simulate relay actions (including time delays) and associated circuit breaker operations (with their time delays).

Electrical Transient Stability is also the foundation for doing custom block diagram modeling for Governor/Turbine, Exciter/AVR, and PSS modeling via the User-Defined Dynamic Models Modules.

The Generator Start-Up module enhances Transient Stability even further. It enables engineers to test the pre-loading of generators before they reach synchronization. This is commonly done under emergency conditions for large Hydro and Nuclear power plants when starting emergency diesel generators.


  • Comprehensive excitation and automatic voltage regulator system models
  • Comprehensive governor and turbine models
  • Detailed Power System Stabilizer models
  • Basis for User-Defined Dynamic models
  • Basis for Generator Start-Up models
  • Built-in pre-load flow
  • Create an unlimited number of events & actions
  • Test almost any disturbance or system change
  • Detailed Induction and Synchronous machine models
  • Capable of three-phase and line-to-ground fault simulation
  • Relays action automatically based upon system levels and device settings
  • Simulate both short and long time
  • Adjustable simulation time and time steps
  • Automatic synchronization check


  • IEEE standard machine models including equivalent, transient & subtransient models
  • Salient pole and round rotor synchronous machine models
  • Single and double cage dynamic models
  • Frequency-dependent synchronous & induction machine models & network models
  • IEEE type turbine/governor and exciter/AVR models
  • Pre-built manufacturer specific exciter & turbine/governor models
  • Detailed modeling of Power system stabilizers
  • Motor mechanical load and machine torsion effect models
  • Apply/clear 3-phase and L-G faults
  • Percent-of-Lengh faults for cables & transmission lines
  • Operate switching actions for circuit breakers and switches
  • Load and/or Generator rejection
  • Generator/Grid/Load level changes including impact (step) & ramp loading
  • Generator mode switching including isochronous/droop/reference
  • Adjust and set exciter/AVR parameters
  • Adjust and set governor/turbine parameters
  • Adjust and set control relays
  • Simulate loss of machine excitation
  • Motor acceleration/re-acceleration simulation
  • Start motor operated values
  • Simulate Automatic Load Shedding


  • Multiple detailed plots, one-line results display, & comprehensive reports
  • Plots for rotor angle & speed, motor voltage & current, mechanical & electrical power
  • Exciter voltage & current plots
  • Motor slip & torque, current & terminal voltage
  • Terminal impedance results for machines
  • Display branch power & current flow
  • Report detailed bus frequency, voltage, volts/hertz, & more
  • Calculate volts/hertz vector difference for buses
  • Superimpose multiple plots
  • Time-varying graphical one-line display of results

Keywords: Bus Transfer, Load Shedding,

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