The pantograph contact force measurement method in overhead catenary system using sparse modelling

Abstract

In recent years, condition monitoring methods have been widely developed. Any failure of the overhead catenary system or pantographs will raise the long downtime of railway operation. Therefore, condition monitoring methods of pantograph failure is required with the overhead catenary system. Furthermore, wear mechanism of contact wire has not been clarified yet due to its complex kinematics between contact wire and pantographs. For preventing these failure efficiently and finding out the wear mechanism of contact wire, the authors have developed a method to measure contact forces of all pantographs during trains passing on sections with sensors installed on the catenary. In the developed method, the contact forces are measured from the sum of dropper forces, inertia force of the contact wire and vertical components of the tensile force of contact wire in measurement section. However, some difficult issues have been left in the method measuring the inertial force from contact wire acceleration at some measurement points. This paper proposes a method selecting effective measurement points of contact wire acceleration. LASSO regression, which is known as one of the sparse modelling technique, is applied to the proposed method so that suitable acceleration measuring points are selected to measure inertia force. The results obtained by the proposed method are shown using dynamic simulation data. It also reports that the proposed method is effective even when the measurement frequency is changed.

Keywords

• overhead catenary system
• pantograph
• contact force
• inertia force
• sparse modeling
• lasso