Automatic inspection of railway carbon strips based on multi-modal visual information

2022

Energies

In the high-speed rail industry, the overhead contact line erected along the railroad is used to supply the electricity to the high-speed train via a pantograph on the carbody’s roof. This work attempts to explore the effect of contact line pre-sag on the contact quality between the pantograph and the contact line. A nonlinear finite element approach is implemented to build the overhead contact line system with accurate description of the pre-sag of the contact line. Through a nonlinear solution, the effect of contact line pre-sag on the contact force is analysed with different train speeds and tension classes. The analysis result indicates the feasibility of tuning the pre-sag to improve the interaction performance at a given speed and tension class. In the low-speed range, the change of pre-sag does not have a significant effect on the interaction performance. However, when the speed increases up to a certain value, the effect of pre-sag on the contact force is nonnegligible. The increase in tension can reduce the sensitivity of the interaction performance to the pre-sag. An optimisation procedure is implemented to obtain the optimal amount of pre-sag for different train speeds and tension classes. The results indicate a necessity to include a certain amount of contact line pre-sag to maintain an excellent interaction performance at high speed.

Section: Literature Reviewmentioning

confidence: 99%

Effect of Overhead Contact Line Pre-Sag on the Interaction Performance with a Pantograph in Electrified Railways

Mei

2022

Energies

“…is simplification is widely accepted as it can accurately describe the response at 0-20 Hz, which is specified to be the frequency of interest in En 50367 [19]. e advanced multibody pantograph model has been developed by some scholars [20,21] to represent the physical configuration, which is of great importance to optimize the parameters [22], develop the controllers [23], and test passive dampers [24] for a better current collection quality. Apart from the simulation in ideal working conditions, the environmental perturbations and the pantograph-catenary errors are appropriately modelled to investigate their effect on the current collection quality.…”

Section: Literature Reviewmentioning

confidence: 99%

Validation and Analysis on Numerical Response of Super‐High‐Speed Railway Pantograph‐Catenary Interaction Based on Experimental Test

Yang

et al. 2021

Shock and Vibration

The numerical tools can be used to facilitate the design of the railway pantograph-catenary system. The validation of the current numerical results is mostly performed at a speed slower than 350 km/h. This paper aims at the validation and analysis of the numerical results at a super-high-speed. The catenary model is constructed based on a nonlinear finite element approach employing the absolute nodal coordinate formulation. A multibody dynamics model is adopted to represent the pantograph. The measurement data are collected by an inspection vehicle equipped with an instrumented pantograph operating at 378 km/h in Chengdu-Chongqing high-speed line. Comparing the numerical simulation and the field test shows that the present pantograph-catenary model can provide reliable numerical results at 378 km/h. The numerical analysis of pantograph-catenary interaction at super-high-speed shows that the trailing pantograph performance does not comply with the assessment standard at 378 km/h. The adjustment of double-pantograph interval and messenger wire tension can effectively improve the trailing pantograph performance.

“…A deteriorated contact quality of the pantograph-catenary mainly reflects in an incremental fluctuation in the contact force. An overlarge contact force causes extra stress and wear in the pantograph strip [2] and the contact line [3] and reduces the system's life expectancy. An inadequate contact force increases the probability of arcing occurrence, which may burn the contact surface and cause electric transmission issues [4], [5].…”

Section: Introductionmentioning

confidence: 99%

Assessment of the Current Collection Quality of Pantograph–Catenary With Contact Line Height Variability in Electric Railways

IEEE Trans. Transp. Electrific.

Duan

Wu³

et al. 2022

The numerical tools are widely used to facilitate the design of the railway catenary. Only radical results are obtained as the current assessment is generally performed without any practical errors. In this paper, the most common error, the contact line height variability, is appropriately included in evaluating the current collection quality. Based on the real-life contact line height data collected from a high-speed network, the heights of the key points in the contact line are extracted, of which the pointwise stochastics is represented by the PSD function. Random samples are generated by the inverse Fourier transform based on the Monte Carlo method. An advanced initialisation procedure is presented to properly include the contact line height variability in the initial configuration. A stochastic analysis with a high cut-off frequency is performed to evaluate a double pantographs-catenary system's current collection quality. Unlike the deterministic result obtained by the perfect design data, the contact line height variability causes uncertainty. The present analysis method indicates some risks of safety accident and contact loss which the traditional simulation cannot capture with ideal design data or low cut-off frequency.