Reliability analysis of TSG19-type pantograph based on time-dependent parameters

Abstract

The aim of the present paper is to study the damage mechanism of the TSG19-type pantographs. Firstly, a rigid-flexible coupled dynamics model is established to predict the pantograph–catenary contact forces with different values of stiffness and damping. A three-dimensional finite element model of a pantograph is then built up to investigate the time history of the stress in a critical section of the pantograph. Dynamics simulations provide the contact forces for the finite element analysis, which the authors needed to extract the stress amplitude and the stress cycles for different values of stiffness and damping. Finally, a reliability model based on the Miner cumulative damage theory is proposed for the TSG19-type pantograph in which the stiffness and damping characteristics degenerate with time. The proposal also takes into account the pantograph life under a given reliability. The results show that the stress amplitude and stress cycles increase when so does the stiffness characteristic and damping decreases. In such way, the stiffness and the damping of the pantograph sets the operating life and the reliability of the component. Therefore, the reliability model appears as a useful tool in the design process of the TSG19-type pantograph since its parameters change with time.