Locomotive “total systems” simulation using SIMULINK

A railway locomotive represents a good example of a complex mixed mechanical and electrical system. Three main applications of an accurate locomotive computer model can be identified. First these models give engineers the ability to study the behaviour of complex equipment prior to the construction phase. Many design problems may be solved before the prototype stage resulting is large cost savings. Secondly for existing equipment a computer model is an invaluable diagnostic tool for technical staff to study the symptoms of various faults and thus expedite the rectification process. Thirdly a computer model can give unparalleled benefit in the technical training area. The actual operation of the system can be studied by personnel in an interactive manner. A total systems simulation of a Queensland Rail 3500 Class electric locomotive has been undertaken for which the `SIMULINK´ dynamic systems analysis package is utilised. This paper presents the techniques being applied to model the power conversion equipment, DC traction motors, mechanical drive train, wheel-rail interaction, control systems, traction transformer and supply systems. The model provides the user with the possibility to view macro effects such as control loop performance and power semiconductor stress levels interactively in the one simulation. Using this model the various control functions such as creep control and motor load sharing can be studied