Case Study: BHP Hot Cars

Scope: Design, manufacture, install and commission the complete electrical control systems for three hot car locomotives at the BHP Port Kembla Coke Ovens.

Because the locomotives are powered from a fixed 230Vdc rail supply, several drive systems were customised for this specialist application. These consisted of two 100kw DC Choppers on each locomotive for control of the traction system (propulsion/retard). Auxiliary converters were also custom built for the application. There were four 230Vdc/415Vac 20kVA inverters per locomotive, which were designed to supply power to the locomotives’ compressors, air-conditioners and other auxiliaries (with sine wave filter) such as lighting and the PLC control system.

The automation system on each locomotive consisted of a Siemens S5 PLC with S7-300 I/O on a Profibus DP network. The PLC control system interfaced with the main traction drive choppers. It controlled the motion of the locomotive based on the command inputs of the operator. A communication link to a land based system was provided for co-ordination with other plant.

The significant challenges of the project were the design and customisation of the equipment, which was required to perform in the extreme conditions of heat and vibration.

Client: BHP Port Kembla