Pantograph Slide Research Articles

PSPMoni: A Robust Wear Monitoring Method of Pantograph Slide Plate

The pantograph slide plate (PSP) plays a crucial role in the daily maintenance of trains by transmitting electrical energy from the contact wire (CW) to the train. Automatic monitoring of PSP wear condition is essential to notice abnormal wear promptly. In field applications, the target PSP edge may be obscured by the rear side PSP due to the operating attitude of the pantograph, leading to false detections and interfering with the field maintenance work. Meanwhile, the scenario of the PSP occlusion is characterized by randomness, which brings a considerable challenge to the reconstruction of the occluded edges. A robust PSP wear monitoring method is proposed to improve the performance of wear detection in field applications, considering the PSP occlusion scenarios. Firstly, the wear area of the PSP is localized using the YOLOv5s model. Subsequently, a fusion of the morphology method and the Canny operator is employed to extract the edge of the PSP. Different occlusion types are identified through detailed observation, and corresponding edge reconstruction methods are proposed for occluded edges. Finally, a robust wear condition evaluation method and five evaluation criteria for assessing wear condition are introduced. Experimental results demonstrate that the system achieves accurate PSP wear detection with an accuracy of 0.6 mm, and the reconstructed edge at occlusion locations closely matches the target edge compared to other automatic systems.

Pantograph Slider Detection Architecture and Solution Based on Deep Learning.

Railway transportation has been integrated into people's lives. According to the "Notice on the release of the General Technical Specification of High-speed Railway Power Supply Safety Testing (6C System) System" issued by the National Railway Administration of China in 2012, it is required to install pantograph and slide monitoring devices in high-speed railway stations, station throats and the inlet and exit lines of high-speed railway sections, and it is required to detect the damage of the slider with high precision. It can be seen that the good condition of the pantograph slider is very important for the normal operation of the railway system. As a part of providing power for high-speed rail and subway, the pantograph must be paid attention to in railway transportation to ensure its integrity. The wear of the pantograph is mainly due to the contact power supply between the slide block and the long wire during high-speed operation, which inevitably produces scratches, resulting in depressions on the upper surface of the pantograph slide block. During long-term use, because the depression is too deep, there is a risk of fracture. Therefore, it is necessary to monitor the slider regularly and replace the slider with serious wear. At present, most of the traditional methods use automation technology or simple computer vision technology for detection, which is inefficient. Therefore, this paper introduces computer vision and deep learning technology into pantograph slide wear detection. Specifically, this paper mainly studies the wear detection of the pantograph slider based on deep learning and the main purpose is to improve the detection accuracy and improve the effect of segmentation. From a methodological perspective, this paper employs a linear array camera to enhance the quality of the data sets. Additionally, it integrates an attention mechanism to improve segmentation performance. Furthermore, this study introduces a novel image stitching method to address issues related to incomplete images, thereby providing a comprehensive solution.

High frequent cyclic ablations of AlSi alloy modified C/C-SiC-ZrB2-ZrC at different temperatures

Modified C/C composites are promising candidates to the advanced piston of internal engine, pantograph slide plate and rapid-fire gun barrel. To understand the corrosion in the working conditions of these thermal components, cyclic ablations of C/C-SiC-ZrB2-ZrC (C/C-SZZ) were carried out in high frequent impacted combustions at different temperatures (700–2300 ℃). Parallel study of AlSi alloy modified C/C-SiC-ZrB2-ZrC (C/C-SZZ-AS) which had lower cost was performed synchronously for comparison. Results indicated that the ablation rates of both the composites went down with decreased temperature while C/C-SZZ-AS presented a faster decline. Compared with C/C-SZZ, the pressure infiltrated AlSi alloy matrix of C/C-SZZ-AS raised the conductivity and specific heat capacity but reduced the emissivity, which led to a lower surface temperature and thermal gradient during ablation. And combined with the better plasticity and toughness of the alloy matrix, C/C-SZZ had stronger ablation resistance below 1500 ℃ in the serious thermal shock. At temperature above 1500 ℃, excessive phase transformation of the AlSi alloy matrix caused more defects and strengthened the mechanical erosion. And then the faster consumption of the AlSi alloy resulted in the greatly worsened ablation property of C/C-SZZ at 2300 ℃.

DEVELOPMENT AND CHARACTERISATION OF PANTOGRAPH SLIDES FOR RAILWAY APPLICATIONS: A SHORT REVIEW

High-speed railways have transformed global transportation, leading to increased economic activity and reduced congestion. Railway development is surging in Asia, encompassing upgrades to existing lines and the construction of new high-speed railways. This article explores the materials, processes, and properties of pantograph slides. A pantograph slide is an important component of top-running rails that enables the transmission of electrical energy from traction substations to moving trains. This review presents the evolution of pantograph slide materials, such as metal slide plates, pure carbon slides, powder metallurgy slides, metal-impregnated slides, and composite slides. The characterisations of pantograph slide properties, such as density, resistivity, hardness, impact, and flexural properties are also reported. This article delves into the utilisation of local materials, particularly carbon derived from palm kernel shells and coconut shells, as well as graphene from petroleum coke, for the development of current collectors. These findings may contribute to the understanding of pantograph slide materials and provide insights into the potential use of sustainable materials in high-speed railway systems.

Study on Friction and Wear Properties of Copper-Impregnated Carbon Slide Plate Under Different Humidity Conditions

The pantograph–catenary system is one of the most commonly used power-receiving modes of metro trains. Its friction and wear performances are related to the safety and stability of train operation. In this study, a copper-impregnated carbon slide plate material, widely used in numerous metro lines in China, is considered as the research object. The problem of abnormal wear of slide plates caused by the decrease in relative humidity in the autumn and winter in tunnels is studied. Current-carrying friction and wear tests under humidity conditions of 20%, 30%, and 40% relative humidity (RH) are performed to reveal the mechanism of seasonal abnormal wear of slide plates and provide a reference for the service of pantograph slide plates under low-humidity conditions. The results reveal that relative humidity significantly influences the wear process of slide plates; further, the wear rate decrease with an increase in relative humidity. As observed by laser scanning confocal microscopy, with an increase in the relative humidity, the mechanical wear of the slide surface is weakened, arc erosion is enhanced, and surface roughness is increased. The Raman spectral scan showed that with the increasing humidity, the graphitization of the surface material decreased significantly, and the molecular structure changed greatly. Scanning electron microscopy (SEM) and energy-dispersive spectrometry (EDS) analysis reveal that under high humidity conditions, a relatively complete oxide film forms on the slide plate and plays a role in lubrication and protection.

On the tribological behaviors of Cu matrix composites with different Cu-coated graphite content

Graphite/Cu composite is widely used in pantograph slide plates. To further understand its lubrication behaviors, the tribological properties of graphite/Cu composites with different graphite content were studied using ball-on-disk wear tests. The results reveal that the composites contain only graphite and Cu phases. The tribological results show that the friction coefficient and wear rate of 7 wt.% graphite/Cu composite were decreased 7.7% and 12.7%, respectively, compared with 5 wt.% graphite/Cu. However, both friction coefficient and wear rate increased with the graphite content exceeding 7 wt.%. The excellent tribological properties of the composites were mainly attributed to the synergistic action of the oxidative trib o-layer and graphite lubricant film, which is composed of graphite, Cu, CuO, and Fe2O3. The wear mechanism of the graphite/Cu composites was mainly abrasive wear, accompanied by adhesion and oxidation wear.

ВЛИЯНИЕ УВЕЛИЧЕННОГО ЗИГЗАГА КОНТАКТНОГО ПРОВОДА НА РАСПРЕДЕЛЕНИЕ МОЩНОСТИ НАГРЕВА ПОЛОЗА ТОКОПРИЕМНИКА МАГИСТРАЛЬНОГО ЭЛЕКТРОПОДВИЖНОГО СОСТАВА

The objective of the study presented in the article is to improve the mathematical model for calculating power losses in a pantograph slide, in particular, taking into consideration the enhanced values of a contact wire zigzag during the motion of an electric rolling stock. The subject of the study is a pantograph slide. The article provides an example for calculating the slide of a pantograph equipped with carbon inserts, illustrating that the heating of the entire structure of the slide is performed stronger when a contact wire is in the extreme position of the enhanced zigzag, while the distribution of heating along the slide is uneven and the greatest power of resistive heating is observed over the shunts. The obtained results of heating power distribution of the slide allow us to supplement the complex model of a thermal state of the pantograph developed at Omsk State Transport University. The versatility of the model allows to investigate various zigzags of the contact wire and to assess the impact on distribution of traction current along the slide, depending on the installation locations of shunts and their quantity.

Interfacial Modification of Ti3AlC2/Cu Composites by Multi-Arc Ion Plating Titanium

Cu matrix composites reinforced with Ti3AlC2 ceramics can be applied for electrical contact materials, such as vacuum contact material or a pantograph slide plate. However, Ti3AlC2 particles substantially decomposed because lattice diffusion is the main way that Al atoms diffused into the Cu matrix and were uniformly distributed. In order to suppress the decomposition of Ti3AlC2 ceramics and improve the properties of Ti3AlC2/Cu composites, the surface of Ti3AlC2 was modified by multi-arc ion plating Ti. The results shows that, with the volume fraction increasing of Ti3AlC2, the decomposition of Ti3AlC2 is exacerbated and the lattice constant of Cu(Al) solid solution is bigger. In the meanwhile, the structure of Ti3AlC2 changes from dispersed granules to flakes, then to a continuous network. Multi-arc ion plating Ti effectively inhibits the diffusion of Al atoms into Cu matrix. The Ti coating reacts with Cu and generates CuxTi in the interface between the Cu and Ti coating, which inhibits the diffusion of Al atoms so as to inhibit decomposition., the inhibition of decomposition of Ti3AlC2 ceramics weakened solid solution strengthening and decreased the content of hard phase TiCx. Furthermore, the good mutual diffusion between CuxTi layer and Cu effectively improves the interfacial bonding strength.

Laminate Design of Carbon-Fiber-Reinforced Resin Matrix Composites for Optimized Mechanical Properties and Electrical Conductivity.

Carbon fiber composites as pantograph slide materials are in the development stage, in which copper is the conductive phase, and the addition form and size need to be designed. Herein, the effects of the copper morphology, the size of the copper mesh on the performance, and the influence of the contact mode between the sliding plate and bracket on the temperature rise were compared and analyzed. The resistivity is 11.2 μΩ·m with the addition of 20 wt% copper mesh, a relative reduction of 91.77%. Importantly, the impact strength is increased by 14.19%, and the wear is reduced by 13.21%; hence, the copper mesh laid in layers is the ideal structure. Further study of the distribution and quality of the copper mesh shows that the resistivity is related only to the quality of the copper mesh; in addition, the number of layers of the copper mesh cannot exceed 16, and it is determined that the best type of copper mesh is 5#. Notably, the performance can be improved by appropriately reducing the thickness of the copper mesh and increasing the aperture while the sliding plate and the bracket are connected by copper mesh with conductive adhesive, which has the slowest heating rate of 2.27 °C/min and the smallest resistance. Therefore, the influence of copper content and distribution on the electrical conductivity are systematically investigated, and the mechanical properties and electrical conductivity are optimized through the design of the laminate structure of the compound material.

Effect of Surface Microparameters on Contact Temperature of Sliding Electrical Contact

Sliding friction pair composed of contact wire and pantograph slide is the key component of train current collection system. Contact temperature is one of the important factors affecting the current-carrying and wear performance of the friction pair. In this article, sliding electrical contact experiments under different experimental conditions were conducted. Based on the measured contour curve of the slide surface, two fractal parameters of the slide surface were calculated by using the structure function method. And the effect of contact current, contact pressure, and sliding speed on the fractal parameters was discussed. A temperature field simulation model of sliding electrical contact considering two rough contact surfaces was established with COMSOL Multiphysics software. The effect of surface roughness and fractal parameters on contact temperature was analyzed by simulation. When other simulation parameters keep constant, the contact temperature first drops and then rises as the average roughness height of the contact surface increases. The average roughness slope of the contact surface has little effect on the contact temperature under high speed and strong current conditions. The contact temperature continuously decreases with the increase of fractal dimension or the decrease of fractal roughness. The conclusions can be used as a basis for further research on the contact temperature characteristics of the friction pair to improve its electrical contact performance.

Copper fiber reinforced needle-coke/carbon composite for pantograph slide and its current-carrying wear performance

Copper fiber reinforced needle-coke/carbon (CF-NC/C) composites with different copper fiber contents have been successfully developed for urban rail pantograph slide block. The mechanical properties of needle coke samples containing 0 wt%, 4 wt%, 8 wt%, 12 wt% and 16 wt% were examined separately. It is found that the presence of needle coke with high aspect ratio, strength and electrical conductivity can greatly improves the physical properties of the pure carbon matrix. Therefore, we have obtained a novel carbon matrix composite. It is also revealed that the optimized CF-NC/C with 5 wt% copper fibers (CF-NC/C-5) composite has outstanding mechanical properties, current-carrying friction wear properties. The density, resistivity, and impact strength of the CF-NC/C-5 composite are 1.8788 g cm−3, 35.18 μΩ·m, 0.16 J cm−2, respectively. In current-carrying friction wear tests (0 A, 5 A, 10 A and 15 A), the CF-NC/C-5 shows an optimum friction wear performance. To avoid agglomeration of copper fibers, the copper fibers are added innovatively during the rolling process and uniformly distributed in the carbon matrix under the tangential force of rolling, which exhibits an improved effect on reinforcing the NC/C composites. Our results greatly advance the development of the needle-coke/carbon composite, which makes the new CF-NC/C composite an ideal candidate for sliding plate material with excellent properties.

Воздействие воздушного потока на аэродинамическое устройство для пантографа

Objective: To evaluate the infl uence of the parameters of current collectors of high-speed and very high-speed trains on the value of aerodynamic resistance. To study the effect of airfl ow on a pantograph aerodynamic device using SolidWorks software. Methods: A comparison of the obtained values of aerodynamic air resistance with those that were produced earlier is carried out. Results: By means of aerodynamic device, it is possible to reduce the speed of the air fl ow effecting the pantograph, to reduce the values of aerodynamic resistance and energy consumption, to extend the service life of current collectors. Practical importance: The proposed design can improve the current collection, which will reduce the load on the overhead line and the pantograph slide, and reduce the energy consumption of electric rolling stock.

Effect of loading spectrum with different single pulsing time on the cyclic ablation of C/C-SiC-ZrB2-ZrC composites in plasma

To support the application for piston of advanced internal combustion engine and pantograph slide plate of high-speed rail, cyclic ablation with different loading spectrums in alternate plasma combustion and compressed air flow were performed by adjusting single impacting time to understand the characteristics of C/C-SiC-ZrB2-ZrC composites in high frequent pulsing fluid at ultra-high temperature. When the loading time increased from 0.5 to 5 s, the ablation rates rose sharply while the surface temperature changed incrementally. Ablation morphology indicated that the change of dominant ablation mechanism from mechanical erosion to chemical reaction resulted in the sharp rise of the ablation rates.

Full density graphite/copper-alloy matrix composite fabricated via hot powder forging for pantograph slide

High-performance copper-based pantograph slide materials play a crucial role in the rapid development of modern urban rail transit urgently. Herein, a full density graphite/copper-alloy matrix composite for pantograph slide has been successfully obtained by the hot powder forging process. The composite exhibits the full density when forging energy density is 307.6 J cm−3. In addition, the influence of different aging treatments on microstructure and mechanical performances of the composite has been studied in detail. The hardness and resistivity of the forged materials are greatly improved after an optimum aging treatment. Simultaneously, the friction and wear performances with or without currency current have been investigated, which demonstrates the friction coefficient can reach the minimum of 0.109 under 35 N. In current-carrying friction, the wear rate of the composite is an extremely small value of 5.5 × 10–5 mg m−1 after the aging treatment, indicating the outstanding anti-friction and self-lubricating performance. All the comprehensive analyses illustrate the full density graphite/copper-alloy matrix composite with excellent mechanical shows an enormous potential for pantograph slide.

A Novel Subpixel Edge Detection Method of Pantograph Slide in Complicated Surroundings

Pantograph slide is a vulnerable component because of the contact and friction between the pantograph and catenary while the train runs with a high speed. Condition monitoring of the slide is a necessary and meaningful work to improve the operation efficiency and reduce the occurrence of accident. It is a hard work to measure the slide abrasion due to the dynamic and complicated environment. In this article, an accurate edge extraction method based on image analysis is proposed, which aims at providing an image metric property based on vision measurement to detect the wear of slide. First, a subpixel edge detection method is proposed. The gradient in horizontal direction is first taken into account, which filters out the nonhorizontal edges. Then, the upper and lower edges of the slide are located using the geometric restriction. The subpixel edge feature are also extracted in the image process, which can be used to the vision measurement system for monitoring the wear condition of the slide. The experiment results shows that the proposed algorithm can precisely detect the subpixel edges of the slide. The measurement error of the slide is less than 2 mm, which demonstrates that the proposed algorithm has a high accuracy in the large field of view.

Online Intelligent Perception of Pantograph and Catenary System Status Based on Parameter Adaptation

Online autonomous perception of pantograph catenary system status is of great significance for railway autonomous operation and maintenance (RIOM). Image sensors combined with an image processing algorithm can realize the automatic acquisition of the pantograph catenary condition; however, it is difficult to meet the demand of long-term stable condition acquisition, which restricts the implementation of online contact state feedback and the realization of railway automation. This paper proposes an online intelligent perception of the pantograph and catenary system (PCS) status based on parameter adaptation to realize fast and stable state analysis when the train is in long-term operation outdoors. First, according to the feature of the contact point, we used histogram of gradient (HoG) features and one-dimensional signal combined with a KCF tracker as the baseline method. Then, a result discriminator located by L1 and hash similarity constraints was used to construct a closed-loop parameter adaptive localization framework, which retrieves and updates parameters when tracking failure occurs. After that, a pruned RefineDet method was used to detect pantograph horns and sparks, which, together with the contact points localization method, ensure the long-term stability of feature localization in PCS images. Then, based on the stereo cameras model, the three-dimensional trajectory of the whole pantograph body can be reconstructed by the image features, and we obtained pantograph catenary contact parameters including the pantograph slide posture, contact line offset, arc detection, separation detection, etc. Our method has been tested on more than 16,000 collected image pairs and the results show that the proposed method has a better positioning effect than the state-of-art method, and realizes the online acquisition of pantograph catenary contact state, representing a significant contribution to RIOM.

Analysis and Research on Current-carrying Friction and Wear of High-speed Train Pantograph Slide and Contact Wire Based on Computer Simulation Analysis

High speed train has many advantages, such as large capacity, fast speed, low cost, small energy consumption, economic and environmental protection, safety and comfort, which has become an important part of high-speed railway in China. Therefore, pantograph catenary system will become an important part of high-speed train. However, due to the vibration of the high-speed train or the irregularity of the contact wire, the pantograph slide plate and the contact wire will produce an arc, which will lead to friction and wear. Therefore, under the complex environment, the pantograph slide plate and contact wire will form a mechanical and electrical wear coupling, which will make the current carrying friction and wear between the pantograph slide plate and contact wire more complex. Therefore, high-speed trains will suffer more problems, which will further restrict the speed-up of locomotives. Therefore, this paper first uses computer simulation technology to analyze the working relationship between pantograph slide plate and catenary of electric locomotive. Then, the friction and wear characteristics of pantograph slide plate and contact wire are studied by experiment.

Effect of flake graphite content on wear between behavior between P/M copper-based pantograph slide and contact wire

In this work, chromium-containing copper matrix com0posites with different flake graphite content (1.8 wt%, 2 wt%, 2.5 wt%) were fabricated by inexpensive powder metallurgy method, and the mechanical properties, friction properties and microstructure of graphite/copper matrix composites were studied. Friction experiments were conducted with copper-based composite materials and copper rings to examine the effect of graphite on the wear of the bow-net structure. During mechanical wear, the wear rate of the copper ring corresponding to the sample increased with the increase of the graphite content in the sample, while the wear rate of the copper ring corresponding to the 1.8 wt% sample was the smallest. In the current-carrying wear process, the wear rate of the 2 wt% sample corresponding to the copper ring is the lowest. Through elemental analysis, it was found that material transfer occurred on the worn surface during wear. In the process of mechanical wear without current-carrying wear is caused primarily by adhesion, abrasion, and oxidation. In the process of current-carrying wear, wear is mainly caused by adhesion, electrical, and oxidative abrasion.

МАТЕМАТИЧЕСКАЯ МОДЕЛЬ СИСТЕМЫ ОХЛАЖДЕНИЯ ПОЛОЗА ТОКОПРИЕМНИКА В РЕЖИМЕ ДВИЖЕНИЯ МАГИСТРАЛЬНОГО ЭЛЕКТРОПОДВИЖНОГО СОСТАВА

Uneven heating of the pantograph slide is the reason for limiting the pantograph removal of the maximum permissible long-term current from the contact network. The highest heating point is observed in the center of the pantograph head relative to the path axis, which can be taken into account when developing a pantograph slide cooling device. Existing models of the thermal state of the pantograph slide do not describe the transient modes of distributed heating of a closed-type structure (euro pantograph head) as a result of the impact of a contact wire in the plan when moving a rolling stock. Existing methods for calculating the heating of the pantograph slide require the use of special programs for the development of its three-dimensional model and significant power of electronic computers. The paper presents a mathematical model euro pantograph head standard design and are equipped with passive cooling system the center through the frame device of the confuser type, which can calculate the load characteristics of the pantograph slide, to evaluate the reduction of uneven heating of its design and to determine the maximal permissible continuous current of the pantograph.

Research on Fault Detection Algorithm of Pantograph Based on Edge Computing Image Processing

Traditional pantograph detection technology has installed a large number of various types of sensors on the pantograph, which is not conducive to the flow characteristics of the pantograph. Traditional detection technology can neither monitor the operation status of the pantograph in real time, nor guarantee the safe operation of the entire train. The existing schemes are only manual solutions, and intelligent real-time monitoring is performed without error, and a lot of labor costs are required. Focusing on the shortcomings of traditional pantographs in sliding plate wear and sliding plate crack detection, an improved mean filtering algorithm is proposed to optimize the image of pantograph, and the adaptive Canny edge detection technology is used to accurately calculate the skateboard wear. Firstly, the improved image algorithm is used to pre-treat the pantograph slide wear and crack length, then the improved mean filtering algorithm is combined with adaptive Canny operator for image optimization detection, and finally the edge calculation is used for crack identification. An optimized real-time on-line detection technology is proposed, which can accurately measure the wear and tear of skateboards and cracks. For different experimental environments, the optimization algorithm proposed in this paper is used to detect pantographs in real time. The experimental results show that, compared with the traditional detection algorithm, the detection accuracy of sliding plate wear can reach 0.5 mm, and and that of sliding plate cracks can reach 0.4 mm. The crack recognition accuracy of skates is as high as 93%.