Modeling And Simulation For Train-Network Coupling System Of High-Speed Railways Based On RTDS

In recent years, high-speed railway develops rapidly in China. The scale of railway construction and the speed level of locomotive are improved significantly. Traction power system acts as an important role in railway, which is needed to feed its loads reliably and safely. Reaserchers on traction power system are started in different ways. Digital simulation is used to study on traction power system widely. It is important to build a real-time dynamic model of locomotive-traction network for the researchs on system optimization. fault reproducing. closed-loop testing of relay.A real-time dynamic model of high speed locomotive-traction network is set up in this paper, dynamic load is mainly analyzed. The traction substation model, traction network model and EMU (Electric Multiple Units) model are discussed separately.The combination model of traction transformer is built based on RTDS, which six kinds of most commonly used traction transformers are contained. With this model, the intertum short fault, turn-ground fault and no-load switching condition of each transformer could be simulated. In the end. the correctness of the model is verified by observing the phase relationship between voltages of transformer secondary side.Traction network unit models are defined at CBUILDER in RTDS. The impedance parameters of traction network are calculated, which is based on CARSON theory, and both AT traction network static and dynamic models are defined according to the defining procedure of CBUILDER, including single line model and multiple track model. With static model, stationary load of traction network could be simulated, in the meantime, active load could be simulated by using dynamic model. At last, the AT traction network models are proved to be correct by comparing it with the relevant models in RTDS and practical conditions.The traction network load model of CRH2EMU is built by RTDS. As three important parts of EMU. the rectifier model, inverter model and traction motor model of CRH2are built respectively. With these models, the complete locomotive model is built according to its actual configuration, which can be applied to simulate train starting, constant speed and accelerating running condition and braking situation. Eventually, the correctness of CRH2EMU model is verified on the basis of harmonic wave content and the main simulation parameters of the traction motors.The dynamic simulation of train-traction network coupling is completed by combining each module of traction power supply system. Current collecting when EMU moving on the single line AT traction network and all parallel AT traction network are studied respectively, besides, the traction characteristic of CRH2EMU is discussed as well. The model of EMU could cross AT station without cutting off current and the simulation results are consistent with practical conditions.