Influence of Surface Roughness of Sliding Friction Pairs on Pantograph–Catenary Contact Resistance

Pantograph–catenary systems are the key equipment for current conduction from power grids to electric locomotives, and within such a system, the property of the slide, especially the contact resistance ( $R_{j}$ ), directly affects its current collection performance. Compared to previous studies, this article focuses on the microscopic roughness parameters, which affects $R_{j}$ greatly. The changing rule of $R_{j}$ under different roughness conditions is studied on 128 groups of data collected from experiments. More importantly, the second-order partial correlation coefficient is introduced to quantify the impact strength of different roughness parameters on $R_{j}$ . Based on this, a multiparameter influence model of $R_{j}$ is established and verified by nonlinear fitting. The results show that the impact strength of the relevant roughness parameters is ranked as $R_{pc}>R_{p}>R_{sm}$ . The conclusion provides a theoretical basis for minimizing pantograph–catenary $R_{j}$ and improving current collection quality. Moreover, it facilitates slide material selection and contributes to new prototype design.