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With the continuous increase of electric locomotive running speed, pantograph arc occurs more and more frequently. The conducted electromagnetic noise caused by pantograph arc will effect seriously normal operation of on-board equipment. With the self-developed electromagnetic noise experimental system, eighty-six groups of conducted electromagnetic noise experiments under different sliding speed, contact pressure, contact current conditions were carried out with single-factor experimental method. Total harmonic distortion (THD) of contact current was proposed and used to reflect the interference level of the conducted electromagnetic noise. The effect of sliding speed, contact pressure and contact current on THD was analyzed. A regression model of the conducted electromagnetic noise was established by using support vector machine (SVM). The independent variable of the model are sliding speed, contact pressure and contact current. The dependent variable of the model is THD. The model parameters were optimized by using particle swarm optimization algorithm. The effectiveness of the regression model was verified with experimental results. It can be used to further understand and forecast the conducted electromagnetic noise. [ABSTRACT FROM AUTHOR]

With the continuous increase of electric locomotive running speed, electromagnetic noise of pantograph arc gets more and more serious and has become a kind of safety risk of electric railway's operation. With the self-developed electromagnetic noise experimental system, 66 groups of radiation electromagnetic noise experiments were carried out by changing contact pressure, contact current and sliding speed. The experimental circuit was powered by a 220VAC low current source. The experimental materials are immersed copper-carbon slide and Cu contact wire respectively. Electromagnetic noise of pantograph arc mainly distributes in 30-570 MHz, and the noise in 30-60 MHz band is obviously higher than that of background. With the increase of frequency, the electromagnetic noise firstly decreases, then increases, and finally decreases to background noise. When the speed is lower than the critical condition of generating pantograph arc, the electromagnetic noise is independent of contact pressure and the amplitude is very small. When the speed is between 30 km/h and 40 km/h, the noise reduces with the increase of contact pressure. When the speed is higher than 50 km/h, the electromagnetic noise becomes intensive and fluctuates with the increase of contact pressure. It can be used to further research on the suppression methods of the electromagnetic noise emission. [ABSTRACT FROM AUTHOR]