Stage 1 – CBD and Sports Precinct Traction Power System Analysis for Commonwealth Games

Background data to Stage 1 Combined team of Yarra and Arup engineers Commenced November 2004 Model simulations commenced beginning April 2005 Pass Assets used in building the model Simulation tests devised by Yarra Trams Simulate worst case running conditions for the Games Ongoing dialogue between Yarra and Arup to resolve data supply problems

Project Objectives Modelling and simulation of the tram operations in the Melbourne CBD and Sports Precinct Assessment of existing traction power network Recommend possible improvements and/or upgrades to allow a safe and reliable 2006 Commonwealth Games service

Scope of Work Undertaken by Arup Gather System and Vehicle Data Build Tram Movement Model Build Traction Power Model Model Power Under Normal and Failure Conditions Carry Out Simulation Tests Analyse Simulation Results Identify Possible Power System Deficiencies Report to Yarra Trams

Simulation Software Traction power simulation consists of two functions: Tram movement calculation (VISION) Power network analysis (OSLO) The linkage between these two functions forms the structure of traction power system simulation

VISION - Tram Movement Simulator VISION stands for Visualisation and Interactive Simulation of Infrastructure and Operations on tram Networks VISION can simulate Yarra’s extensive tram network including real time representation of tram services throughout the system

OSLO – Traction Power Simulator OSLO stands for Overhead System LOading The program was initially produced to predict the performance of an AC electrified system The program has now been developed to predict the performance of a DC electrified system

Input Data Supplied by Yarra Trams Substation Data Traction Power Network Data Tram Vehicle Data Tram Stop and Timing Point Data Track Infrastructure Data Timetable Information Simulation Scenarios

Typical Output Data From Model Tram Pantograph Operating Voltages Trolley Wire Current Ratings Substation Equipment Ratings Feeder Cable Current Ratings

Timetable Scheduled Daily Timetable Commonwealth Games Timetable Modelled between 6:30am to 9:30am 310 trams enter the CBD and Sports Precinct 20 seconds dwell time at each tram stop Commonwealth Games Timetable 325 trams enter the CBD and Sports Precinct 20 min. peak running period from 8:00am to 8:20am 90 seconds headways on Flinders St. and Clarendon St. Modern low floor trams on routes 48, 70, 75, 112, and 96

Simulation Scenarios Normal Power Scenario (all substations in service) Power Failure Scenario Rectifier unit at Crombie Lane substation out of service Westgate Freeway substation out of service Main feeder at Flinders Street tie substation out of service Tram Entry Time Perturbation Approach Used to simulate the real situation on the tram network 20% of trams enter the simulation on time 80% of trams enter the simulation 1 to 59 seconds late Entry time perturbation can be changed

Simulation Results Normal and Failure Scenarios for Scheduled Timetable and the Commonwealth Games Timetable Data processed: Substation Voltages Substation Loadings Feeder Cable Currents Overhead Conductor Currents Parallel Cable Currents Tram Pantograph Voltages Tram Power Loadings

Typical Graphical Outputs – Power Graphs Scheduled Timetable Games Timetable

Typical Graphical Outputs – Voltage Graphs Scheduled Timetable Games Timetable

Typical Graphical Outputs – Journey Log Graphs Scheduled Timetable Games Timetable

Simulation Results The analysis suggests: The network may require some additional feeder and parallel cables to accommodate the Commonwealth Games timetable Some adjustments to the tram headways may have to be made Yarra Trams should consider converting the existing Flinders Street tie substation to a full substation at some point in the future to improve the power network reliability

Discussions With Yarra Trams Simulation results have been presented to Yarra Trams Discussions have been held with Yarra electrical and power engineers Yarra engineers are happy with the model approach and with Arup’s recommendations We need to run the latest version of the Commonwealth Games timetable Confirm possible upgrades to the network