Geometric effect of a railway contact wire on dynamic interaction between a pantograph and an overhead line

초록

In this paper, we simplify the dynamic interaction between a pantograph and an overhead-line with the pre-sag to one dimensional equation. The simplification leads to the Mathieu equation because of the stiffness variation over a span. We derive an optimum amount of the pre-sag to minimize the fluctuation of contact forces by applying the harmonic balance method [6] to the Mathieu equation. In addition, through the numerical simulation of pantograph-overhead-line dynamics, we show that the pre-sag improves current collection quality, especially at the resonance of the pantograph-overhead-line system, but the pre-sag deteriorates current collection quality at the higher speeds than the resonance speed. Field on-line test for a Korean tilting train confirms that the pre-sag improves current collection quality at 160km/h near to the resonance speed. We also discuss the effect of the pre-sag on current collection quality for a high-speed pantograph-overhead contact line system when a train moves at 300 km/h.