Research On The Impact Of Electromagnetic Induction When Urban Rail Transit Crossing The Yangtze River Via The Dashengguan Bridge Of The High-speed Railway

With the development of electrified railway and urban rail transit in China, it is inevitable that AC and DC electric railway lines are adjacent, and run in parallel. The Ninghe urban rail transit line passes the Dashengguan Bridge in parallel with the Beijing-Shanghai high-speed railway line and the Shanghai-Wuhan-Chengdu Passenger Dedicated railway line. This means that one urban transit line and two high-speed railway lines share the bridge floor of Dashengguan Bridge. As a result, the AC traction network may cause dangerous induction voltage in the nearby DC traction network conductors through electromagnetic induction. Therefore, in order to ensure the normal operation of the DC trains as well as the safety of maintainers, it is essential to effectively assess the electromagnetic induction impact among the high-speed railway and the urban rail transit and to present suitable and efficient protective measures.Based on the field survey results, the distribution pattern of AC and DC electric railway lines of the Dashengguan Bridge and some related parameters of the traction network are described in this paper. Then, the mechanism of electromagnetic induction between AC and DC railway lines and the potential hazards caused by induction voltage are analyzed.An equivalent circuit model of AC and DC railway lines is built according to the practical features, and the TRANAS software is used for simulation. The induction voltage and current curves of DC traction network conductors, when the Beijing-Shanghai high-speed railway line and the Shanghai-Wuhan-Chengdu Passenger Dedicated railway line under different operating conditions and T-R short circuit, are obtained from simulation. Consequently, the varying rule of induction voltage is concluded yet. The shielding effectiveness of the overhead ground wire and steel truss of Dashengguan Bridge is also analyzed via simulation.The simulation results are compared with the measured data to validate the model. And then the impact of electromagnetic induction between high speed railway lines and urban rail transit lines can be assessed.An induction voltage absorption device used for the DC electric railway is developed to reduce the electromagnetic induction impact of the DC traction network imposed by the AC traction network. Technical measures are proposed for ensuring the normal operation of the DC trains and protecting maintenance staff.