1. Electrical Systems Electrical Engineering in Railways –Rolling Stock –Communications & Control –Signalling –LV Installations in Stations and Buildings –Electrical Systems

2. Electrical Systems

3. Electrical Systems High Voltage Aerial Lines and Underground Cables Substations 1500V dc Traction System –Overhead Wiring –Traction Return Power Supply for signalling operation, communication equipment, station and buildings, etc LV installations in Railway Tunnels and Yards

4. Electrical Systems Statutory Environment –Rail Safety Act 2002 –Electricity Supply Act 1995 –Electricity Supply (Safety & Network Management) Regulation 2002 –RailCorp is one of the Electricity Distributors in NSW

5. High Voltage A.C. Distribution System Standard Voltages –11kV –33kV –66kV –132kV Modes of transfer –Overhead Transmission Lines –Underground Cable

6. HV Aerial Lines Conductors –Copper –Aluminium (AAC or Aluminium Alloy) Conductor Supports –Wood Poles –Steel Poles

7. HV Cables Conductors –Copper Construction –Paper insulated lead sheathed –XLPE Configuration –Underground –Galvanised Steel Troughing / Ground Line Troughing

8. 1500V D.C. System Electric Trains in NSW Run on 1500V D.C. –Power is supplied from traction substations to trains by means of the overhead wiring (OHW) system –Trains collect current through pantographs sliding under the contact wire –Current returns to the substations via traction rails

9. Traction Substations Switchgear –AC Circuit Breaker –DC Circuit Breaker Transformers & Rectifiers –Convert the high voltage ac supply to 1500V dc Control and Monitoring –SCADA (Supervisory Control and Data Acquisition)

10. Traction Substations Substation Spacing –Typically 4km to 15km –Depends on a number of factors including Train loads Track grades Losses OHW types Train headways Electrolysis

11. Overhead Wiring (OHW) Overhead Wiring Systems in RailCorp –Simple Catenary One or two contact wires supported by a catenary wire –Compound Catenary A main catenary supports an auxiliary catenary, which in turn supports the contact wire –Contact Only

12. Overhead Wiring Tensioning Modes –Fixed Anchored Wires rigidly anchored at both ends of the wire run Tension in the wire varies with temperature Wire sags down at high temperatures –Regulated Tension Tension is the wire is held approximately constant

13. Overhead Wiring (OHW)

15. Overhead Wiring

16. Power Supplies Supplied from High Voltage Distribution System –Generally from the 11kV Network Transform voltage to 415V or 240V Signalling Supplies –Generally two independent source of supplies are provided –“Normal” supply from RailCorp HV Distribution System –“Standby” supply from local electricity distributor Power supplies to stations, buildings, workshops and other LV installations.

17. Electrical Systems Challenges –Reliability On Time Running Single Contingency (Except for OHW) Double or Triple Contingency at Critical Locations Design to minimise restoration time after failures –Safety Statutory Clearances Permit System Safety in Design