Condition monitoring system of wheel-rail contact force utilizing PQ monitoring bogie (Basic design of the analysis tool and analysis of the derailment coefficient)

Abstract

The derailment coefficient is calculated from wheel-rail contact forces and it indicates the running safety of the railway vehicle especially in sharp curves. The derailment coefficient is affected by many factors such as the track irregularities, the vehicle parameters and the friction characteristics between wheel and rail. Therefore, monitoring of the derailment coefficient is desired to evaluate the running safety of the vehicle. Recently, a new monitoring bogie which can collect time series data of the derailment coefficient during commercial operation has been developed, and a large scale data is collected. However, there was no way to use such a data efficiently because an efficient method and an analysis tool have not been developed. In this research, a new analysis tool which can easily handle a large scale data and assist analysis of the derailment coefficient has been designed using MATLAB. In addition to measuring the derailment coefficient, the wheel load reduction and the track irregularity of twist are also measured. The tool can extract points where the derailment coefficient increases from a large scale data, and quickly show detailed information. On the basis of the information displayed on the user-interface, the data analyst can identify factors that increase the derailment coefficient. Not only analysis focused on a particular curve, but also the tool has the function for comparison of some curves. Analysis of the time change of the derailment coefficient is also possible. This paper shows the basic design of the analysis tool and gives some examples of analysis using this tool.

Keywords

• railway
• derailment coefficient
• monitoring
• wheel-rail contact
• data analysis