73 / 2017-04-15 11:00:12

Study on the Characteristics of Over-voltage of High-speed Train Body After lightning

High-speed EMU,over-voltage on train body,lightning current,grounding parameters

High-speed railway in China is mostly located in the countryside and the catenary is exposed to the sun and rain, resulting in high possibility to be stroked at any time and the train cannot operate as usual. This paper built the high-speed Electric Multiple Units (EMU) circuit model on the basis of the structure of high-speed EMU using OrCAD/PSpice. The over-voltage caused by lightning current running into train body was studied, as well as the characteristics and propagation regularity of law. The results showed that the voltage on EMU body would greatly rise. The amplitude of over-voltage was related to the amplitude and steepness of lightning current. When the amplitude of lightning current is 20kA, the maximum over-voltage of EMU body, always on the third train body, is 15.21kV. The influence of the grounding parameters on the over-voltage caused by the lightning current flowing through the train body was studied by simulation. Based on the above analyzing results, the reasonable value of grounding resistance was proposed which was between 0.5 ῼ and 0.7ῼ. Finally, two kinds of methods to cut down the over-voltage on train body were put forward. They were connecting a resistor in parallel with a filter capacitor and reducing the grounding resistor value. The effectiveness of them methods were also verified. The results of the study can provide a theoretical basis for engineering applications.