29. Three-dimensional simulation method of overhead contact lines and pantograph dynamic interaction

Three-dimensional simulation method of overhead contact lines (OCL) and pantograph dynamic interaction has been developed, to help the development and design of OCL and pantographs as well as to investigate the cause of accidents related to OCL and pantographs.
Although the actual OCL was modeled in 2D space previously, the new method can model the OCL in 3D space as actual one and evaluate current collection performance.

With this method, it is possible to predict the dynamic motion and the deformation of the OCL and pantograph by construction 3D OCL and pantograph model.
It is possible to perform simulations to reproduce the 3D behavior of a pantograph which has some small contact strips (Fig. 1), analyze the position of the contact wire in a curved section of track and crossing section (Fig. 2), and consider static structure change of the OCL caused by temperature change (Fig. 3), which were difficult to do with the conventional method. Figure 3 shows that the contact force decreases at Part A where the height of contact wire is up-gradients, while it increases at Part B where the height of contact wire is down-gradients, because the contact wire is pulled up at the center of its span by temperature change.
In addition, it is possible to perform two coupled simulations, one is coupled simulation with numerical calculation of air flow in tunnel, another is with vehicle dynamics simulation. The former can analyze the change of contact force of a pantograph when train enters a tunnel. The latter can evaluate the relative position of the contact wire and pantograph considering the inclination of the entire pantograph caused by vibration of vehicle.