RAILSIM Load Flow Analyzer (LFA) has been developed for the comprehensive and flexible modeling of any electrical network of any complexity, RAILSIM LFA analyzes system electrical capacities, power demand, power costs, effects of regenerative braking and many other electric network issues. RAILSIM LFA analyzes DC (direct current) electrical networks.  For AC (alternating current) network analysis, the AC LFA add-on module is required.


RAILSIM LFA lets you graphically monitor up to 3 independent locations
and variables during the solution process.

RAILSIM LFA analyzes the loads, potentials and regenerative braking receptivity on a given system supplying power for the operation of electrified rail under prescribed operating conditions. The base LFA model is built and maintained in RAILSIM Editor and includes:

  • Substations
  • Feeders and Returns,
  • Power Costs

LFA uses the defined model, and train operations and unconstrained electrical load requirements derived from RAILSIM TPC, as well as pertinent user-defined parameters to understand the physical plant of the electrical network.  RAILSIM LFA also accommodates user-specified train operational information and substation and feeder schedules. With this information, LFA simulates the electric load throughout the network, providing results such as total power consumption, peak power loads, substation loads, system losses and train voltages. RAILSIM LFA has these features/capabilities:

  • Support for rail networks of any complexity,
  • Mixed fleet operations (trains with different characteristics and consists), including none, some or all with regenerative catenary capability,
  • Deterministic (non-variable) and stochastic (variable) train operation/headways,
  • Support for headway-based inputs with identical train types,
  • Support for unlimited variation in train types, train lengths and schedules,
  • Connections between different tracks (jumper wires),
  • Cross track connections between running rails,
  • Conductor gaps (bridgeable or unbridgeable by the train) in overhead or running rails,
  • Overhead trolley wire isolation switch status (on or off at given time duration),
  • Substation outages for specified time durations,
  • Positive feeder or negative feeder outages for specified time durations,
  • Static loads on or off at given time duration to reflect yard or shop loads, including import capability for static load profiles that vary by time of day,
  • Rail to earth leakage resistance included in the model to generate rail potential profiles, to facilitate further analysis of touch voltages and stray currents,
  • Support for single rail return for traction current at specified locations,
  • Different size of overhead conductors (trolley wires and contact wires) in different sections,
  • Different sizes of running rails (and different size/composition of third rail sections) in different sections,
  • Power, energy and cost analysis for each power zone that supplies a group of traction substations,
  • Receptivity of regenerated power (for each train simulated and for the overall system), and
  • Energy saving due to regenerative braking (for each train simulated and for the overall system).


Substation characteristics and associated feeders are easy to define in RAILSIM LFA.

RAILSIM LFA supports custom specification of:

  • Positive and Negative Feeder Conductor Locations
  • Track Circuit Section Boundaries (Supply Conductor Gaps)
  • Overhead Line/Track Resistance Change Points
  • Generic Load and Resistance Point Locations
  • Track (Supply Conductor) Isolation Switches
  • Track Leakage Resistance Change Points
  • Supply/Return Jumpers
  • Train Volume Monitoring by Location
  • Energy storage devices, such as flywheels and storage batteries, and substation diode drainage
  • Substation Loads
  • Power Cost Profiles, which can include Peak Power Constraints of three types:
    • Instantaneous
    • Fixed Interval
    • Sliding Interval


Electrical network attributes are defined only at locations where they change,
based on the chainage/stationing system.

LFA Typical Output

Text and graphical output is easily generated in RAILSIM Report Generator. The Load Flow Text Report Wizard supports the simultaneous specification of detailed and summary reports, including:

  • Train reports with time and distance-based electrical demand
  • Voltage at train pantograph or third rail shoe
  • Substation loads and voltages
  • System electricity costs predictions, including energy consumption and a variety of demand-based rate structures

The Load Flow Plot Wizard permits simultaneous specification of up to 11 different plots per selected analysis. Typical output includes:

  • Detailed train reports with time and distance-based electrical demand,
  • Voltage and current at train pantograph or third rail shoe,
  • Substation loads and voltages,
  • Time over current ("current limit") reports that highlight potential breaker trip occurrences,
  • Low voltage report, highlighting all occurrences of trains experiencing less than desired voltage at the third rail shoe or pantograph,
  • Prediction of system electricity costs, including energy consumption and a variety of demand-based rate structures (which can vary within the simulated territory by substation utility feed),

 


RAILSIMŪ is a registered trademark of SYSTRA Consulting, Inc.
Customized training, database development and simulation algorithms are available.
Copyright 1999-2007 SYSTRA Consulting, Inc.
 All Rights Reserved


Click any image
below to see full size.

 

 



 


LFA Maximum/Minimum Rail Potential Plot

 


System Snapshot Report details the state of the rail electrical network at a user-specified time.

 

 


System Receptivity Report