Fuzzy Integral Based Multi-Sensor Fusion for Arc Detection in the Pantograph-Catenary System

The pantograph-catenary subsystem is a fundamental component of a railway train since it provides the traction electrical power. A bad operating condition or, even worse, a failure can disrupt the railway traffic creating economic damages and, in some cases, serious accidents. Therefore, the correct operation of such subsystems should be ensured in order to have an economically efficient, reliable and safe transportation system. In this study, a new arc detection method was proposed and is based on features from the current and voltage signals collected by the pantograph. A tool named mathematical morphology is applied to voltage and current signals to emphasize the effect of the arc, before applying the fast Fourier transform to obtain the power spectrum. Afterwards, three support vector machine-based classifiers are trained separately to detect the arcs, and a fuzzy integral technique is used to synthesize the results obtained by the individual classifiers, therefore implementing a classifier fusion technique. The experimental results show that the proposed approach is effective for the detection of arcs, and the fusion of classifier has a higher detection accuracy than any individual classifier

Power Quality in Electrified Transportation Systems

"Power Quality in Electrified Transportation Systems" has covered interesting horizontal topics over diversified transportation technologies, ranging from railways to electric vehicles and ships. Although the attention is chiefly focused on typical railway issues such as harmonics, resonances and reactive power flow compensation, the integration of electric vehicles plays a significant role. The book is completed by some additional significant contributions, focusing on the interpretation of Power Quality phenomena propagation in railways using the fundamentals of electromagnetic theory and on electric ships in the light of the latest standardization efforts

Metrology Infrastructure for Energy and Power Quality in DC Railway Systems

L'abstract è presente nell'allegato / the abstract is in the attachmen

Contactless rail track condition analysis approach using image matching

Demiryolu ulaşımı geçmişten günümüze kadar yaygın olarak kullanılan en önemli ulaşım türlerinden biridir. Demiryolu sistemleri yük ve yolcu taşımacılığında yaygın olarak kullanılmaktadır. Demiryolu hattında birçok arıza oluşabilmektedir. Demiryolu araçlarında veya hatlarında oluşabilecek arızalar ulaşımı olumsuz etkilemektedir. Bu arızaların erken teşhis edilmesi için durum izleme oldukça önemlidir. Genellikle ray, travers ve bağlantı plakalarından kaynaklanan arızalar ortaya çıkmaktadır. Bu çalışmada, demiryolu hattını oluşturan bileşenlerin izlenmesi için görüntü işleme tabanlı bir yöntem önerilmiştir. Sağ ve sol rayların izlenmesi için iki tane kamera kullanılarak bir deneysel yapı oluşturulmuştur. Demiryolu hattı üzerine kurulan deneysel yapı ile farklı durumlarda videolar alınmıştır. Alınan videolar üzerinde YCbCr renk uzayı, Canny kenar çıkarımı ve köşe tespit algoritması kullanılarak demiryolu bileşenleri tespit edilmektedir. Bu çalışmada ray, travers ve bağlantı plakasının birleştiği kısımlar tespit edilmektedir. Oluşturulan deneysel yapı ile farklı tür demiryolu hatlarında da görüntüler alınarak sonuçlar test edilmiştir.Rail transport is one of the most important modes of transport commonly used in the past to the present. Rail systems are widely used in passenger and freight transport. Many failures can occur on railways. The failures occured on railway tracks or vehicles may negatively affects the transportation. Condition monitoring is very important for the early detection of this failure. The failures especially due to rails, sleepers and tie plates. In this study, an image processing-based method has been proposed for monitoring the components of the railway. An experimental structure using two cameras for monitoring of right and left rail is formed. Samples videos in different situations were taken with the experimental structure founded on the railway track. The railway components were detected on sample videos by using YCbCr color space, Canny edge detection and corner detection algorithms. In this study, the rail, the tie plate and the joins of the traverse are determined. The experimental structure is used on different railways and the result are tested.Bu çalışma TÜBİTAK (Türkiye Bilimsel ve Teknolojik Araştırma Kurumu) tarafından desteklenmiştir. Proje No: 114E202

Railway defect detection method: A review

The railway is indeed one of the main transportations means in the world. However, with the rapid development and advancement of the railway industries, more railways accidents occur mainly due to its defects which result in economic losses. Traditionally, the railway defect detections process which is deems to be dirty, difficult and dangerous are done manually by the railway maintenance workers. In the recent years, many sophisticated equipment such as portable detectors, track inspection trolleys, track comprehensive inspection vehicles, etc had been developed. This article outlines two main mode of inspection namely static and dynamic inspection, which are commonly used in the railway defect detection and maintenance work. Furthermore, the railway inspection equipment used by the major countries are summarized and the impact on railway inspection based on deep learning and artificial intelligence are appropriately predicted

30th International Conference on Condition Monitoring and Diagnostic Engineering Management (COMADEM 2017)

Proceedings of COMADEM 201

Advanced monitoring of rail breakage in double-track railway lines by means of PCA techniques

This work describes a classifier designed to identify rail breakages in double-track railway lines, completing the electronic equipment carried out by authors. The main objective of this proposal is to guarantee the integrity of tracks before the railway traffic starts working. In addition, it facilitates maintenance tasks providing information about possible breakages. The detection of breakages is based on the analysis of eight currents provided by the electronic equipment, one per rail, at the ends of the section (emitting and receiving nodes). The imbalance that occurs among the value of these currents implies that there is at least a breakage in the track section under analysis. This analysis is conducted according to three phases. The first one identifies whether there is a breakage, and, in that case, the damaged track is identified. The second phase provides information about which rail is broken (internal, external or both of them) in the previously identified track. Finally, if there is only one breakage, the third phase estimates its most likely zone along the track section. This situation is considered as a classification problem, and solved by means of the Principal Component Analysis technique. This means that a significant number of measurements is required for every breakage pattern (types of breakages) to be considered. Due to the difficulty of having real data, the proposal has been validated using an 8km-long double-track hardware simulator specially designed by the authors, with specific localizations for breakages

Vibration, Control and Stability of Dynamical Systems

From Preface: This is the fourteenth time when the conference “Dynamical Systems: Theory and Applications” gathers a numerous group of outstanding scientists and engineers, who deal with widely understood problems of theoretical and applied dynamics. Organization of the conference would not have been possible without a great effort of the staff of the Department of Automation, Biomechanics and Mechatronics. The patronage over the conference has been taken by the Committee of Mechanics of the Polish Academy of Sciences and Ministry of Science and Higher Education of Poland. It is a great pleasure that our invitation has been accepted by recording in the history of our conference number of people, including good colleagues and friends as well as a large group of researchers and scientists, who decided to participate in the conference for the first time. With proud and satisfaction we welcomed over 180 persons from 31 countries all over the world. They decided to share the results of their research and many years experiences in a discipline of dynamical systems by submitting many very interesting papers. This year, the DSTA Conference Proceedings were split into three volumes entitled “Dynamical Systems” with respective subtitles: Vibration, Control and Stability of Dynamical Systems; Mathematical and Numerical Aspects of Dynamical System Analysis and Engineering Dynamics and Life Sciences. Additionally, there will be also published two volumes of Springer Proceedings in Mathematics and Statistics entitled “Dynamical Systems in Theoretical Perspective” and “Dynamical Systems in Applications”

Advanced Control Strategies for Voltage Source Converters in Microgrids and Traction Networks

Increasing concerns regarding global warming caused by greenhouse gases, which are mainly generated by conventional energy resources, e.g., fossil fuels, have created significant interest for the research and development in the field of renewable energies. Such interests are also intensified by the finitude availability of conventional energy resources. To take full benefit of renewable energy resources, e.g., wind and solar energy, interfacing power electronics devices are essential, which together with the energy resources form Distributed Generation (DG) units. If properly controlled and coordinated, the optimal and efficient operation of DG units, which are the main building block of rapidly emerging microgrid technologies, can be ensured. In fact, the optimal and efficient operation of any energy conversion systems, e.g., microgrids, traction networks, etc., necessitates some sorts of control strategies. Being structured into two main parts and exploiting two-level Voltage Source Converters (VSCs), this thesis introduces several control strategies in the context of microgrids and electrified traction networks. Although the proposed approaches of this thesis are mainly tailored for two-level VSCs, the methods are equally applicable to other converter technologies. In the first part, adopting an optimization-based loop shaping approach, a vector current control strategy for three-phase grid-tied VSCs is proposed. The proposed control strategy is able to independently regulate the direct and quadrature (dq)-components of the converter currents in a fully decoupled manner and shows very fast dynamic response similar to the existing methods. In order to extend the applicability of the proposed vector control method to single-phase systems, a countermeasure is also proposed. In single-phase systems, to form the orthogonal component of the current needed to create the dq-axes, the converter current is phase-shifted a quarter of a fundamental period. This phase-shift is the reason of strongly coupled dq-axes and oscillatory dynamic response in such systems. To obviate the need for the problematic phase-shifting, adopting a Fictive Axis Emulator (FAE), the orthogonal fictive current is created concurrent to the real one. In such a case, utilizing the proposed decoupled vector control strategy and the FAE, the dq-currents of single-phase converters are also regulated in a fully decoupled manner. Moreover, in this part, using a generalized version of the optimization-based loop shaping approach, three voltage control schemes are proposed for the voltage regulation of islanded microgrids. Since the dedicated loads of islanded microgrids are not fixed, the loop shaping is simultaneously carried out for various operating points of interests, i.e., for various combinations of the load parameters. Two single-stage control strategies and a cascade one are proposed: (i) a single-stage PI-based Multi-Input Multi-Output (MIMO) controller, (ii) a single-stage PI-based MIMO controller in conjunction with resonant terms, which is able to compensate for the adverse impacts of nonlinear loads, and (iii) a cascade PI-based MIMO controller. The cascade control scheme utilizes the proposed decoupled vector control strategy as its inner loop for regulating the converter current. In the second part, this thesis focuses on electrified traction networks and addresses a power quality problem in such networks, i.e., catenary voltage fluctuations. The Active Line-side Converter (ALC) of modern locomotives is utilized as STATic COMpensator (STATCOM) in order to inject reactive power to compensate for the adverse effects of catenary line voltage fluctuations. To determine the proper amount of reactive power, several control strategies belonging to the PI-controllers family are proposed: (i) a P-controller, (ii) a PI-controller, and (iii) a gain-scheduled PI-controller. Among the proposed approaches, the gain-scheduled strategy provides the best performance. The gain-scheduling is performed through identifying the catenary inductance at the connection point of the locomotive to that. The inductance identification is carried out by the injection of harmonic current through the ALC and monitoring its effect on the locomotive voltage. Despite its acceptable performance, the gain-scheduled approach shows several shortcomings. Therefore, utilizing the optimization-based loop shaping technique, a high-order voltage support scheme is also proposed. The proposed high-order scheme does not need any online tuning and/or modification while provides excellent performance for various operating points