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Three types of electromagnetic noise between pantograph and catenary

For a long time, people gives a lot of attention to the EM noises that generated by the electrified railway system. Studies have shown that the disturbance was mainly from two aspects: one is the conducted disturbance feed back to the power grid which was generated by the traction system (including the power-frequency harmonic emission and switching noise), the other aspect is the pulse noises that originated from the pantograph-catenary subsystem. In fact, the latter one contributes a lot to the whole railway system's radiated disturbance. These RF noises, not only possibly pollute the external EM environment, but also let the train running under a high EM noise environment, for the emissions are always moving along with the train. It may introduce interference to the wireless communication or the train control system, and increases the risk to the safety. In this paper, we proposed three types of typical pulse electromagnetic noise emission of the pantograph-catenary sub-system, which based on analysis of physical mechanism and a number of on-site test results.