Wireless monitoring of the dynamic behavior of railway catenary systems

Abstract

During the last couple of decades the railways have experienced a steady growth in high-speed rail. However, there still exist a considerable amount of infrastructure that is designed for older and completely different scenarios. This is also true when considering the power supply to the electric railways where a two level catenary system is commonly used. For the power supply to be reliable and uninterrupted under higher speeds there must be strict static and dynamic requirements. The current power supply systems for old electric railway lines, often called soft catenary systems, are characterized by their design for an optimal quasi-static behaviour. This paper primarily explores the behavior of the dynamic system using a newly developed monitoring system. This includes multiple wireless sensors mounted in arbitrary positions chosen to be beneficial in the description of the fundamental motions, and with a range above 700 m. However, for any monitoring scheme to be efficient, it is important to establish relevant dynamical system conditions and to verify existing systems behavior. This requires a full-scale instrumentation program and the associated system identifications. That is, for the railway catenary system it must be included several sensors measuring response at different points within one or several spans as well as close to the cantilevered supports. The system can then assess catenary response components such as uplift, frequencies, damping and mode shapes. In the current paper this is further explored using the location of Hovin station in Norway.