パデ近似を用いた鉄道用レール周波数依存線路モデル作成法

Abstract

This paper proposes a simplified distributed-parameter line model of rails considering frequency dependent effect. Surge characteristic of rails is different from that of overhead line because the rails have sleepers, which are made of wood or concrete. The earth return and space impedance are calculated by the theory of image assuming the zero potential plane is located at the penetration depth. The impedance of the rails vs. frequency characteristics are measured using an impedance analyzer to estimate a shunt admittance of the sleepers and ballast. The rails including many sleepers and ballast are expressed by a Semlyen's line model installed in ATP-EMTP. Its accuracy is confirmed by comparisons between a simulated transient response using the ATP-EMTP and a field test result. The proposed model improves the simulation accuracy in high frequency region and a computation time step of a transient is increased comparing with the conventional model. This model is applicable to the surge analysis on railway signaling system using ATP-EMTP, which is widely used in power system analysis.