Upgrading Pantograph Performance Using Variable Stiffness Devices (2nd Report: Development of Variable Stiffness Device and Control of Dynamic Characteristics of Pantograph)

The authors proposed a new technique to improve the current collection performance of pantographs. For this purpose, the pan springs, which are usually coil springs, are replaced with variable stiffness device, and its stiffness is varied so as to suppress the contact force fluctuation between pantograph and catenary. The 1st report outlined the proposed technique and validated it by the numerical simulation. This report firstly details the developed variable stiffness device necessary for applying the proposed technique and verifies the stiffness variability of the device. The device has two air springs arranged so that they are opposite to each other, whereby the stiffness of the device can be varied by altering the air pressures of both air springs. It then presents the vibration test for the variable stiffness device equipped pantograph. The test result shows the dynamic characteristics of pantograph can be controlled by varying the stiffness of the device.