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The outdoors insulator is an important component of the high-speed railway traction substation, which is of great significance to maintain the stability of transmission line and ensure the normal operation of transmission network. Once there is a fault for the insulator, it will cause serious transmission failure and economic loss. Therefore, a method is proposed to detect the abnormal areas of outdoors insulator in high-speed railway traction substation based on object detection and generative adversarial networks. First, we employ Faster RCNN to locate the area of insulator from the input image of traction substation. Then, the image of insulator obtained from the first step is fed into our designed generative adversarial networks to generate fake image, which is a normal image of insulator. Finally, multi-scale structural similarity algorithm is used to realize the anomaly detection of insulator and visualize anomalous areas. Experiments results on Heishan traction substation show that the proposed method is effective.

Unified mathematical modeling of AC traction power supply system is the key to realize digital simulation. Based on the multi-conductor transmission line model, a unified mathematical model of traction network suitable for different power supply modes is constructed. On the basis of introducing the constitution of traction power supply system, the general mathematical model of traction power supply system is generated by establishing the mathematical model of primary power supply network, deducing the general equivalent circuit of traction substation and establishing the chain structure model of traction network. On the basis of chain network structure, the general simulation mathematical models of AC traction power supply system based on power supply arm, substation and whole line are established respectively, and the corresponding power flow calculation method is given. Using the existing components of the RTDS model library, a 24-pulse traction rectifier transformer, a traction network and a power machine disposable model are built under the RTDS platform for simulation research of subway traction power supply system. Through parameter setting and fault simulation, simulation under various working conditions is carried out. The example calculation shows that the model has good generality and high accuracy, and is suitable for simulation of traction power supply system of high-speed and heavy-load electrified railway.

At present, with the rapid development of urban rail transit, the design requirements of urban rail power supply system are getting higher and higher. This paper mainly studies the simulation of urban rail transit power supply system with inverter feedback device, in order to provide data support for power supply system design and energy consumption analysis from the aspects of system modeling and simulation. First of all, the model of traction substation is established, including rectifier unit and inverter unit, and the calculation principles and algorithm implementation process of DC network power flow calculation and AC network power flow calculation are also analyzed next. Finally, the power flow distribution and energy utilization effect of the power supply system considering inverter feedback device are evaluated. The results show that the inverter feedback device installed in traction substation plays an important role in reducing traction network voltage, improving energy efficiency and saving operation cost.

The braking energy absorption of urban rail transit has always been an important issue. The use of supercapacitors for energy absorption is an efficient way. In order to make the supercapacitors of each substation better recover the braking energy, the traction substation is equivalent to the voltage source and the virtual impedance, and then the virtual impedance is configured to achieve the average distribution of braking current among the supercapacitor braking energy absorption devices in the adjacent traction substation, or as far as possible. For such voltages and resistances are uncertain, the multivariate online solution is difficult to achieve by traditional methods. In this paper, through the equivalent and simplification of the circuit topology, and the introduction of the genetic algorithm, the simultaneous solution of voltage and resistance is realized. Four different situations are analyzed.

Робота виконана у відділі автоматизації електричних систем Інституту електродинаміки Національної академії наук України. Дисертація присвячена розв’язанню задачі створення і впровадження багаторівневої і багатофункціональної галузевої системи моніторингу електротехнічного обладнання тягових підстанцій і електричних мереж залізниць України. Виходячи з результатів виконаного аналізу практики експлуатації впроваджених більш як на 150 тягових підстанціях локальних цифрових пристроїв моніторингу параметрів режимів роботи обладнання обґрунтовано нагальну потребу в розширенні переліку і покращенні якості виконуваних цими пристроями функцій та їх об’єднанні в єдину багаторівневу інформаційну мережу. Виконано математичне моделювання елементів системи централізованого автоблокування залізниць, нормальних та аварійних режимів роботи ліній живлення. Розроблено метод автоматичного моніторингу параметрів режимів і визначення місця пошкодження фази на землю ліній електропостачання пристроїв сигналізації, централізації і блокування. Розроблено технічні вимоги, принципи побудови, визначені функції, структура і створена багатофункціональна інтегрована система моніторингу обладнання господарства електрифікації та електропостачання Укрзалізниці. Перший зразок системи впроваджено на базі трьох її тягових підстанцій. This thesis addresses issues of developing integrated monitoring system for Ukrzaliznytsia’s railroad facilities and management equipment in context of engineering requirements, implementation principles, product development and deployment. New method for 1-phase fault location in rail signalling control (RSC) was designed. Equipment handling of local digital monitoring devices at more than 150 railroad substation has been analyzed. Urgent demand for enhancement in quantity and quality of their functions as well as merging of those devices in one multilevel information system were shown. Numerous experiments to determine voltages, currents, loads and capacitances of RSCs had been carried out. In each case there were experiments with specially assigned capacitors between each phase and earth and without them. It has been proved that adding capacitors lessens voltage unbalance and increases accuracy of fault location. Capacitors’ values have been chosen based on RSC parameters and electromagnetic interference from nearby CSF and 27,5 kV power backup lines. That interference is based on induced voltage and emf on account of their capacitive coupling and mutual inductance. Harmonic composition of experimental phase currents and voltages has been analyzed. Functional patterns for RSC operating mode parameters have been specified. Those patterns depend on capacitors’ values; distance to location of the fault; mutual disposition of RSC, CSFs and 27,5 kV power backup line. New mathematical model was developed based on those patterns. The model uses twin-T network with isolated neutral taking into account inductance-capacitance coupling of RSC and adjacent CSFs and 27,5 kV power backup lines. Analysis of different 1-phase fault location methods at lines with isolated neutral has been made. It has been shown that the best methods would be one-sided online ones, i.e. methods that imply usage of measuring equipment only at one end of the line and are based on usage of amplitude-phase spectrum of line’s currents and voltages. Method for automatic monitoring of RSC operating modes parameters with fault location function has been devised. This method implies adding special capacitors in each phase at the beginning of the line connected in Y-connection with earthed neutral point; measuring phase currents and voltages vectors; using residual current’s vector and amplitude voltage’s value of first and upper harmonics of faulty phase as main monitoring parameters. This method’s implementation into traction substation equipment’s monitoring system does not require tripping of the line, ensures reliability of gained data, lessens voltage unbalance, extends the work period of RSC equipment, makes it’s easier and faster to locate a fault, increases accuracy of fault location. Theoretical and practical studies of factors that affect accuracy of fault location at RSC have been carried out. Revised relationship between line’s operating modes parameters and fault location parameters have been attained. Those were used to improve above mentioned method’s algorithm. It has been proved that fault location’s error won’t exceed 1% in case of external influence’s absence. Depending on presence of external factors, maximum relative error would be in -0,6…-12,8% interval. Specifications, design concept, functions and structure of multi-functional integrated monitoring system for Ukrzaliznytsia’s railroad facilities and management equipment have been provided. Introduction of system’s first sample on 3 Ukrzaliznytsia’s traction substations basis has made it possible to provide operating personnel with reliable data about state and operating modes of controlled energy objects. Improved reliability, effectiveness and operational safety of railroad facilities and management equipment were achieved.

The solid insulators are widely used in alternating current gas-insulated switchgear (GIS) equipment in high-speed railway traction substation. They have both mechanical support and electrical insulation functions. AC withstand voltage test is required before they are put into operation. In this paper, the series resonant circuit is theoretically analyzed, and the transient voltage change process of GIS solid insulators during sudden flashover is simulated and analyzed in the MATLAB/Simulink computing environment. The 3D electric field simulation of basin insulators and typical solid insulators with insulation support is carried out by using ANSYS electric field simulation platform. The withstand voltage test of the real interval of GIS is carried out to obtain the opening of circuit breaker. The relationship curves between Q, I and applied voltage U of solid insulator under two operating conditions are obtained. The results show that after flashover of solid insulators in series resonant circuit, the arc will be extinguished immediately after high voltage drop, and the recovery voltage will be established for a long time. The typical electric field distribution of solid insulators has concentrated area of local electric field, and flashover in field withstand voltage test starts in high field strength area. The research results of this paper provide some theoretical support for the field voltage withstand test of solid insulators used in AC GIS with series resonant circuit.

В статье рассмотрен вопрос замены масляных выключателей на тяговой подстанции «ЯДРИНО» с питающим напряжением 220 кВ. Проведённые мероприятия позволят улучшить технико-экономические показатели функционирования тяговой подстанции при минимальных финансовых затратах на оборудование, обслуживание и материалы. Замена масляных выключателей на элегазовые обеспечит повышенный уровень надёжности электроснабжения и качество электроэнергии в пределах норм, соответствующих действующим стандартам., This article deals with the issue of replacing oil circuit breakers at a traction substation with a supply voltage of 220 kV. These measures allow us to improve the technical and economic indicators of the functioning of the traction substation with minimal financial costs for equipment, maintenance and materials. Replacing oil circuit breakers with SF6 ones will provide an increased level of reliability of power supply and quality of electric power within the norms that correspond to current standards.

This paper describes the typical field of power electronic converter in the branch of traction substation. The main attention is paid to problematic of AC-traction substation. This topic is solved here due to the just started conversion from DC-traction system to AC-traction system in Czech Republic. These new AC-traction substations use semiconductor power converters for purpose to minimize un-symmetrical unbalance of input current consumption, to compensate reactive power, to filtrate high-order harmonics etc. This article describe and compare basic attributes of these modern topologies of AC-traction substation.

This paper describes the control of multilevel converter for substation balancer. The topology of substation with electronic balancer is described. The principle of power symmetrization and reactive power compensation is introduced in paper. Designed control algorithm for independent current control is main goal of this paper. This control is based on the calculation of required current by Steinmetz’s method. The paper presents simulation results of designed prototype of substation with rated power of 12.5 MVA for 25 kV / 50 Hz traction catenary.

Voltage unbalance in power systems feeding AC traction power systems is a worldwide known problem. One of the main aspects of this problem is the negative effect of voltage unbalance on motor loads causing operating problems and economic damage. It is necessary to perform unbalanced power flow studies and calculate voltage unbalance indexes to assess this negative effect of voltage unbalance and the develop of compensating measures during the design stage. Usually, calculations of the AC traction power supply system and the distribution network feeding it are carried out separately during the design of new lines of railways electrified by alternating current (AC) and reconstructing of existing ones. This approach is a source of deviations in the power flow studies because the lack of consideration of mutual influences between the traction power system and the distribution power system. In this paper, we compare a digital model in which the traction power supply system and the distribution network are modeled separately with a model that considers mutual influences between the traction and external power supply systems, including power flows through the traction network caused by the distribution network (transit currents). For digital modeling of these processes, authors used ETAPTM software with eTraXTM package. It allows to run unbalanced power flow studies when the generation and load are being changed over time, including train movement. During a separate simulation of the traction power system and distribution network, traction network was modelled using the equivalent sources connected to traction substation buses and the distribution network was modeled taking into account the fact that traction load was given from the simulation of the traction power system. The traction load was considered as lumped loads connected to the traction substation buses.At the same time, in both cases, the unbalanced power flow study was carried out by the phase domain method. Based on the results of two models comparison, it was concluded that the combined model containing a traction power supply system and distribution network, is more effective in terms of improving the accuracy of assessment voltage unbalance in accordance with current regulatory and technical documents on power quality.

Considering the inefficiency and insecurity of traditional training methods which focused on outdoor work, one design of traction substation simulation system based on Unity3d framework is proposed by combining three-dimensional scene with real-time infrared simulation system. Also, we propose a more accurate computing model of declination angle \(\delta^{\prime}\) to improve the infrared simulation system. After that, our simulation result proves that the improved infrared simulation system can describe temperature distribution on the surface of objects accurately, which makes the training mode more concrete and vivid.

The topology of a converter-based traction substation is proposed in this paper to solve the power quality problems in traditional power supply systems (TPSSs). Its series–parallel structure is suitable for traction applications. The topology of power circuit is presented, and its working principle is analyzed in depth. For the cascade–parallel structure, constraints for its stable operation are given. The DC voltage sharing performance of the active front end (AFE)-based cascade inverters is analyzed. In the control of the rectifier, the DC feedforward control is adopted to improve the dynamic performance. The mathematical model is established for the parallel structure at the output, and the active and reactive power decoupling control strategy based on shared synchronous bus is proposed. Moreover, the calculation method of the active power and the reactive power is introduced. The basic functions of the system and the performance of cascade–parallel structure at the output side are validated based on MATLAB/Simulink.

The unequal spread of load between traction substations along a subway line is analyzed. The impact of energy crossflow between feeder zones of different substations over their output buses on the current loads of traction substation is evaluated.

The electrified railway static power conditioner not only has the ability to control the two-phase active power, reactive power and harmonic current of the traction substation and the basic functions of reducing the negative sequence but also can complete the active power fusion of the traction power supply arm on both sides, which can significantly improve the power quality of the railway traction power supply network is widely used in railway traction power supply systems. The research background, common topology, compensation principle and typical control strategy of railway power regulator are reviewed. The topology of the railway power conditioner is explained from the single-module and modular multi-level topologies, and it is considered that the new power electronics topology, advanced control strategy, soft switching technology, high-power application, and power electronic integrated system Stability, etc. will be the future research direction of railway power regulators.

Commuter line in PT Kereta Commuter Indonesia (KCI) is a means of transportation that transports passengers in Jabodetabek. In the Bogor-Manggarai crossing, several Traction substations are supplied. This study aims to find out how the capacity of substation power capacity in Bogor - Manggarai crossing towards the loading of the current Commuter line operating pattern and how the capacity of substation carrying capacity to increase the loading of KRL operating patterns at peak hour. For this reason, primary and secondary data are analyzed using the calculation formula. Among them: total Commuter line weight, tractive substation power capacity in the Manggarai-Bogor crossroad, power capacity based on headway, power capacity based on maximum current, required capacity, and cross capacity used on multiple lines. It can be concluded that the capacity of the cross-Manggarai-Bogor electric power in the normal 4-minute headway according to GAPEKA 2017 can be fulfilled by the Bojonggede Traction Station. And at peak hours conditions Bojonggede Traction substation can support with 3.75 minutes headway and can be reduced to 3 to 2 minutes.

Traction power supply system (TPSS) is an important part of the electric railway. Lightning is one of the important factors that endanger the safe operation of TPSS. The impact of lightning on TPSS can be divided into lightning fault and lightning disturbance. Due to lightning disturbance also generates high-frequency components, which cause the relay protection mistrip in traction substation. In this paper, wavelet energy moment is used to recognition lightning disturbance of TPSS. Firstly, in order to obtain transient signals of TPSS, simulation model of the TPSS is built and it simulates three kinds of transient signals, such as normal signals, lightning fault signals and lightning disturbance signals. Then the wavelet transform is used to extract the energy moments of each frequency band of the three types of signals. Thus, wavelet energy moment statistical graphs of three types of signals are obtained, the wavelet energy moment statistical graph is analyzed and its distribution characteristics are analyzed. Based on this, the lightning disturbance recognition criterion is proposed. Finally, the recognition criterion is verified by the simulation signals. The results show that the recognition method can effectively recognize the lightning disturbance signal of the TPSS.

The electric locomotive operation leads to complex nonlinear dynamic characteristics of the power signal of the traction substation, which makes the calculation of the power quality index based on the steady state signal processing technology have large errors. Therefore, based on power systems computer aided design/electromagnetic transients including DC (PSCAD/EMTDC), the simulation model of common electric locomotive converter is built. The characteristics of traction substation power signal are analyzed and compared with the measured power signal. The internal relationship between the line impedance change of traction electric multiple units (EMU) and grid signal fluctuation is analyzed. Finally, some transient power quality evaluation methods are proposed, and the instantaneous normalized distortion energy index (INDEI) is used to evaluate the transient power quality of the measured power signals. This index can accurately identify the signal jumping type and help to improve the reliability of dynamic load power quality analysis.

Smart grids concept provides for broader application of distributed generation (DG) plants which can operate using renewable energy sources in parallel with power accumulators (PA); in which case PA are important smart grids elements possessing number of useful features, such as load curves leveling, providing uninterrupted power supply for especially important consumers, power and frequency damping, ensuring steady operation of DG plants, enhancing power quality. The article is dedicated to issued related to PA use for non-traction consumers power supply; in which case, PA and control algorithms for DG plants voltage and frequency were studied with respect to reduction in the dip depth in power supply systems for normal and emergency modes. The study was carried out in the MATLAB system based on network cluster model performed based on DC link that connects non-traction consumers with DG plants and PA with traction substation 110/27.5/6.3 kV. The computer modeling detected that the use of continuously connected PA on DC buses DC link allows significantly reducing non-traction consumer's depth of dip in case of temporary shut down of the main power supply. In addition, the use of look-ahead control algorithms results in reducing the depth of dip in comparison with traditional ones, considerably decrease of transition process time, voltage and frequency overshoot value in case of power supply temporary shut down of non-traction consumers, and in case of distant three-phase fault.

In conventional electric railway transportation systems supplied in DC, regenerative braking energy cannot be generally sent back to the electric power grid due to the non-reversible diode rectifiers used in traction power substations. However, a DC substation could be made reversible by connecting an inverter in parallel with the existing rectifier, hence allowing the energy recovery. This paper presents the development of a simulation program to quantify the braking energy that could be recovered with the addition of this power electronics device.

We developed control logic demanded for ESS to simplify SS facilities, replacing SS with Battery Post. We report the verification test results about ESS for stable railway operation use in order to compensate for voltage drops, and control logic using train data to reduce battery size and extend battery life.

APM, Automated People Mover, is a kind of driverless Automated Guideway Transit (AGT) system, which is usually used to undertake passenger transport tasks in large airports. APM is different from the common urban rail transit system, which uses three-phase AC traction power supply system. In order to provide parameters for the design of traction power supply system in the early stage, the traction calculation method of APM system and the simulation method of traction power supply system are studied. In order to reduce the active power loss of the power supply rail, the minimum power loss model of the power supply rail is studied and an adaptive particle swarm optimization algorithm (APSO) with dynamically changing inertia weight (DCW) is used to optimize the location of the traction substation. The simulation results show that the proposed method can effectively optimize the location of traction substation and improve the utilization of electric energy.

In this paper, the influence of grounding wire configuration of traction substation on observed transient overvoltage at some electric machines, those are diode rectifier, series reactor and so on, is experimentally measured. According to our previous experiences, a diode rectifier is the weakness against lightning and making the transient voltage smaller can increase the reliability of traction power supply system against lightning. Now, two grounding wires are installed separately at Ooi-Futo Substation. Throughout our experiments, by connecting them and by disconnecting the one end of grounding wire near the rectifier, it was confirmed that the transient voltage observed at diode rectifier could be decreased. In this paper, some experimental results will be explained in detail.

The harmonic currents generated by electrical locomotives may induce the traction network resonance and harmonic current enlargement. Wave-trap high-pass-filter (HPF) can suppress the harmonic resonance and filter the high-frequency harmonic currents. This paper considers three positions for the wave-trap HPF, which installed in traction substation (TS), section post (SP) or middle of traction network (TN), its filtering performance is analyzed respectively. For the line mixed with AC-DC locomotives and AC-DC-AC locomotives, the active power filter (APF) is added in TS to filter low-order harmonic currents. The filtering performance is also analyzed while the wave-trap HPF is installed in three installation positions respectively. The result shows that the high-frequency harmonic resonance can be suppressed by the wave-trap HPF in any of three installation positions. More specifically, the THDU of TN bus is reduced from 13.87% to less than 7% with the wave-trap HPF. The best performance of the hybrid filter can reduce the THDU to 1.79%, when both the APF and the wave-trap HPF are installed in TS.

With the continuous development of high-speed railways, more and more electronic equipment is introduced into high-speed railway traction substations, and the grounding grid is an important facility to ensure the normal operation of electrified railways and the safety of people and equipment in the station. The safety performance evaluation of the grounding grid of high-speed railway traction substation is essential for the design of the grounding engineering. In this study, The safety performance of the grounding grid wasevaluated by a method of moment under a power frequency grounding fault and the lightning strike of the substation. The results show that while the grounding impedance of the traditional evaluation standard grounding grid meets the requirements, the contact voltage under the grounding grid power frequency grounding fault and the mesh potential difference under the lightning strike do not meet the safety standard.

Field test results of transient performance at a DC traction substation are reported in this paper. The test simulates an invasion of a lightning surge from one of phases of an AC grid. An arrester installed at a bus of AC side is discharged, and the discharge current is injected into the grounding mesh via a grounding wire for the surge arrester. The voltages on the primary and secondary windings of the rectifier transformer are measured. The results clarify the transient responses of the DC traction substation. The amplitude of the induced voltages on the primary windings is 76 % of that of the invaded phase. It shows a possibility that the failure due to lightning does not always occur on the invaded phase. In addition, the induced ratio of the secondary winding is 15 %, which is relatively high considering the winding ratio of the transformer of 5.3 %.

In D.C. traction power supply system, high resistance grounding fault is one of the difficult problems for reliable power supply. Because the load current of trains is much higher than the grounding fault current, it is impossible to detect the fault from the over-current relay. The detection of three phase unbalance which is conventionally applied in A.C. power supply system is not applicable in D.C. traction power supply system, neither. Considering such a peculiarity of D.C. traction power supply, grounding fault detection based on the potential difference between rails and grounding mesh at traction substation is practically used for grounding fault detection at D.C. substation for railway in Japan. The rails of D.C. railway are electrically floating, not grounded intentionally, to avoid stray current caused by D.C. traction loads. Also, the rails are part of a D.C. traction power supply system, and can be an approach path for lightning to the substation. Studying the characteristics of the rail potential and the leakage current to the ground is also important for knowing the tendency of electricity when lightning current flows. In this study, the details of the behaviors of rail potential in urban D.C. railway system are investigated not only by the measurements in practical fields, but also by the calculations of D.C. traction power supply circuit. According to the previous experiences during a few decades, the rail potential near traction substation tends to be negative while it is positive at the location of train because of the voltage drop caused by the current in rails. Our measurement of rail potentials in Tokyo urban area, however, indicated that the rail potentials became positive in many cases. This result contradicts to the common sense of railway power supply engineers. We carried out circuit simulations for many cases and it was found that the rail potential tends to be positive in the traction power supply circuit with many trains. As conclusions, the rail potential becomes positive in the area where train operation density is high while it becomes negative where that is low. In addition, it was confirmed that two factors influence the fluctuation of the rail potential by continuous measurement of the rail potential. First, as the output current of the substation increases, the current leaking from the feeder circuit to the ground increases and the rail potential becomes negative. Second, the rail leakage resistance decreases due to rain, the leakage current increases and the rail potential becomes negative. In this paper, the details of our measurements and calculations will be shown.

This paper presents the Dynamic and Transient modeling of the light rail transit (LRT), including the passenger loading and unloading effect in stations. The EMTP-RV model of the system has been developed to show how the traction power substation (TPSS)system is reacting while train load changes from one station to the other in time domain analysis. Effect of using stationary super capacitor is also considered to reduce starting inrush current and absorbing regenerative breaking. Mechanical breaking is also included in the model which is used when train is approaching the station. The base and enhanced models and analysis presented in this paper can be used for the analysis of dynamic and transient behavior of the large light rail transit system in various modes of operation.

An innovative application of an energy storage system as replacement of traction substation has been proposed and tested to simplify power supply system configuration. The tests were carried out at Ohnuki Susbstation on the Uchibo Line of East Japan Railway Company in 2017 and 2018. This paper presents an overview of our proposal and some key figures of the test to explain the feasibility of the system.

The rational use of regenerative braking energy for urban rail transit trains directly affects the voltage safety of the traction power supply system and the electric braking function of the train. It is also of great significance for the implementation of train traction energy saving. This paper proposes a scheme of train regenerative braking ground absorbing device based on super-capacitor energy storage. It adopts multiple modular Buck/Boost DC conversion topology to realize bidirectional control of electric energy and stabilize the secondary utilization of traction network voltage and regenerative electric energy. According to the scheme of this paper, the energy storage device was developed and verified in the engineering of the Guangzhou Line 6 main line traction substation. The test indicators have met the design expectations.

Electrified railway traction power supply system is directly powered by 110 kV or 220 kV (some 330 kV) high-voltage power grid. The uncertainty, non-linearity, and asymmetry of traction loads like the electric locomotives and electric multiple units (EMUs) exert the negative sequence and harmonics impact on the high-voltage transmission network. In order to evaluate the impact of the uncertainty and asymmetry of traction loads on the high-voltage transmission grid, a probabilistic three-phase power flow model of transmission network considering the probability model of traction loads is proposed. First, the power probability model of traction loads is established according to the running characteristics of traction loads. Second, the Monte Carlo simulation method is applied for the probabilistic three-phase power flow model calculation considering the traction loads. Finally, the simulation calculation is carried out on the balanced IEEE-14 bus three-phase test system. The results show that the asymmetric traction loads cause the unbalance of the grid nearby to deteriorate. The further away from the traction substation, the smaller impact of the traction loads.

The paper is dedicated to the estimation of instantaneous reactive power in a DC traction power system. Currently, the integral and frequency methods are mostly used to define reactive power and do not give high accuracy in the calculations of power balance or cannot describe the essence of physical processes. The problem is complicated in DC electric transport systems due to random impulse character of voltages and currents. As a comparison, the calculation of reactive power according to various approaches was performed for the DE1 electric locomotive. It is suggested that the instantaneous reactive power should be used for the analysis of electromagnetic exchange processes in DC power systems. The paper shows the definition and main formulas for defining the instantaneous reactive power taking into consideration the random character of voltage and current. Numerical calculations together with statistical analysis were performed for two variants of experimentally recorded voltages and currents: the first one - on the bus-bar of traction substation, which supplies the section with the Pendolino trains in Poland and the second one - on the current collector of the VL8 electric locomotive in Ukraine. They confirm the validity of the aforementioned method.

One of the main parameters determining railway efficiency is capacity. The main volumes of transportation of goods and passengers on the railways of Russia and most other countries are carried out along electrified sections. The traction power–supply system (TPSS) of electrified railways that provides the energy for transportation is at the same time an element limiting train handling through the sections. Thus, there is an urgent task to evaluate the railroad capacity in terms of energy supply, followed by the development of measures improving bottlenecks in the power–supply system. The paper presents the results of a study on improving a capacity calculation model of the electrified railways. An analysis of the “accuracy of calculation–railroad capacity” dependence and the electrical connection between traction substations is carried out. A traction power–supply system model of greater accuracy is developed through a procedure of model-result verification. Diagrams explaining the presence of electrical connection are presented. Electrical connection of both dc and ac adjacent traction substations is provided by means of activated sectional switchers of the overhead system and section switchboxes of the corresponding intersubstation zone. The developed traction power–supply model makes it possible to improve the accuracy of calculating the capacity of electrified railways.

In urban electric railway transit systems, rails are used to navigate trains, as well as to provide the returning path of the train's electric current to the traction power substation (TPS). Due to electrical resistance of rails and the rail-to-ground conductivity, a part of the train's returning current to the TPS flows into the ground, which is called stray current, which causes different problems such as an increase of rail potential. In this regard, a model of an electric train with a TPS, running rail, and third rail is simulated in MATLAB/Simulink. In the simulated model, the amounts of stray currents in different soil types, with and without collection mats, are compared. Afterward, to calculate the amount of stray current in the presence of the stray current control method considering different soil types through finite–element (FE) method (FEM), a UIC54 rail with insulated fastening equipment is modeled in FEMM 4.2 and analyzed with 2-D FEM. Finally, a comparison of efficiency of stray current collection mats in different soil models for both simulation in MATLAB/Simulink and FEM is also presented. The obtained results verify the accuracy of the simulated and modeled system in real conditions of electric railways.

Continuous growth of freight traffic, an increase in the share of heavy and connected trains, the commissioning of powerful electric locomotives on the main railways requires the implementation of measures to strengthen and improving efficiency of the traction energy system (TES).The analysis of the possibilities of traditional means of increasing the voltage in the traction network with increased traction loads showed that there is a need to create a new, additional means of amplifying the TES, which would have no less potential to increase the voltage in the traction network than the capacitive compensation equipment, but would have a more significant reliability and better performance.This means can be a booster transformer designed to increase the voltage at one of the phases of the traction substation [1, 2].The energy relationships in the traction energy system (TES) of alternating current are considered with the inclusion of a power multifunctional booster transformer (MF BT), the compensating winding of which is connected to the compensating unit. It is taken into account that the electric locomotive current and voltage on the susceptor are not sinusoidal in nature. The analysis of electromagnetic processes is carried out at different values of the capacitance of the compensating device (UPPRK), equal to 1, 038 mF; 1.75 mF and 1.94 mF, which corresponds to a change in reactive power from 2.5 to 5 MVAr.The article shows the expediency of selection and the adjustment of compensating unit connected to the compensating winding of the MF BT, proceeding from the minimum of the exchange energy determined by the presence in the TES of capacitive and inductive energy storage devices. It is established that when a VL-80r electric locomotive operates, the required capacity, determined by the minimum exchange energy criterion, is 0.2 - 0.3 mF less than the capacity calculated according to the current regulatory documents.The investigation includes the analysis of simulation results of instantaneous currents and voltages in the traction energy system when the locomotive is operated in traction mode when there is a power booster transformer in the TES, the compensation winding of which is connected to the compensating unit. The article shows the possibility of selecting parameters of the balancing unit connected to the compensating winding of the MF BT, based on the minimum exchange energy that occurs in circuits with non-sinusoidal sources and consumers of electricity.The efficiency of using the criterion characterizing the energy exchange was confirmed at choosing parameters of the compensating installation of the compensating winding of the MF BT at its location on the traction substation.

The article deals with the problem of the locomotive asynchronous traction motor control with the AC diesel-electric transmission. The limitations of the torque of the traction motor when powered by the inverter are determined. The recommendations to improve the use of asynchronous traction motor of locomotives with the AC diesel-electric transmission are given.

All car of Tohoku-Shinkansen is equipped with the regeneration brake. This car is returning electric power to the Catenary line when it is braking. Regenerative power can improve the energy efficiency if other cars can use regenerative power. But the regenerative power flows back to the grid via the traction substation when other train does not exist in the same section. At this time, the regenerative power flowing back is not metered. This study is to measure the regenerative energy that flows back to the grid. We need determine the equipment capacity if installing the electric energy storage systems and the RPC for use up regenerative power. By using a linear programming, we determined the optimal capacity of the electric energy storage systems and the RPC.

Summary. The problem arising at the design of electric locomotives with asynchronous traction drive are considered. The electrical scheme provides the possibility of individual (by axle) control of traction motors. This allows realizing the operational disconnection/connection of one or more axles in the automatic mode, with account of actual load. In Part 1 of this paper, the complex computer model based on the representation of AC traction drive as controlled electromechanical system was developed. The description of methods applied in modeling of traction drive elements (traction motors, power converters, control systems), as well as of mechanical part and of "wheel-rail" contact, was given. In Part 2, the results of dynamic electromechanical processes modeling in various modes of electric locomotive operation (start and acceleration, traction regime in straight and curve railway sections, wheel-slide protection, etc.) are presented. In perspective, based on the developed model, the evaluation of locomotive's energy efficiency at the realization of various control algorithms must be obtained.

Power quality was always a major concern in designing an electric supply system for railways. Since electric railcars are usually single-phase loads, they draw high amounts of negative sequence component of currents, in addition to harmonic contents and transient currents. Therefore, many compensation methods were examined to improve the power quality indices. The active power quality conditioner (APQC) can be considered as an ideal compensator for high-speed railway, which contains a three-phase converter connected to the traction substation through a step-down transformer. However, with the growth of railway loads, the nominal rating of the solid-state high-frequency switches of APQC increases seriously, which in turn, results in an exponential growth of the cost of power-electronic switches. Therefore, for a very high-capacity railway system, it is not economic to apply an APQC. As a solution, a combination of APQC with the static VAr compensator is proposed in this study, which reduces the rating of APQC, and improves the power quality of the system. Simulation results validate the pre-defined hypothesis. Moreover, the performance of APQC depends on the DC-link operation, for which genetic-algorithm optimisation has been applied to obtain an optimum design of a stable DC-link voltage.

—“The Technical Maintenance Regulations of Russian Federation Railways” and “The Arrangement Regulations of the Russian Federation Railways Traction Power Supply System (TsE-462)” set out clear requirements to ensure minimum voltage in the aerial contact wire for freight and high-speed passenger train movement. These requirements are confirmed by the Norms of the European Electrotechnical Standard EN 50163 (1995). However, the voltage norms at traction substations (TsE-462) are in contradiction to the maximum continuous voltage in the aerial contact wire demanded by Railway Research Institute (VNIIZhT) and accepted by EN 50163 Standard. This paper proposes using continuous voltage at traction substations in the normal operating mode in the range of from 3600 (the minimum value) to 3700 V. The maximum voltage (3700 V) was obtained as a result of electrical calculation of the traction power supply system at the track sections with hard mountainous track profile while running trains with an increased weight of 6300–9000 t or two combined trains with a combined weight of 12000 t with powerful electric locomotives of 2ES6, 2ES10, and 3ES10 series. This voltage value was confirmed by long-term operation on a Tyumen–Yekaterinburg–Perm–Balezino track section of 923-km length with voltage stabilization at the level of 3650 V at the traction substations. The voltage levels at the traction substation buses are provided by a contactless automatic control system (CACS) with ±0.6% inaccuracy. The maximum voltage in the traction substation buses is acceptable and equal to maximum aerial contact wire voltage (4000 V) under the recuperation mode.

On the main railways in Russia, two types of current in the contact wire are used: dc voltage of 3 kV and ac voltage of 25 kV with a frequency of 50 Hz. Therefore, prospective electric rolling stock should have double the power. Improving the capacity and structural speed of locomotives is based on the use of asynchronous traction motors (ATDs) with a squirrel-cage rotor allowing increasing the tractive force and the weight of the train and the capacity and speed of cargo delivery, increasing reliability and reducing life cycle costs, and increasing service life. Electrical equipment for such rolling stock should be used when working from either contact system, dc or ac. In this article, the scheme of power circuits is considered using the example of a module of a traction drive in one bogie of dual-system electric locomotives. It is proposed to use the secondary winding of the traction transformer as a choke of the input filter when powered from a dc contact system. Regulation of operation modes of asynchronous traction motors is carried out from static semiconductor converters with a two-tier structure. Input transducers provide the exchange of electric energy between the contact system and the intermediate link of dc voltage, and the output converters regulate the traction motors by changing the magnitude and frequency of voltage on the stator windings of ATD depending on the speed of the locomotive and its operating mode. 4QS input converters and output converters are autonomous voltage inverters of the intermediate ac: in the case of single-phase input and output, they are three-phase. The basic ratios are given to determine voltages and currents of 4QS converters, to determine the variable component of a rectified current 4QS converter, and to formulate requirements for a resonant L2C2 filter configured for a frequency of 100 Hz. Expressions are given for determining the ratio of the input power of the converter, as well as recommendations for determining the basic parameters of electrical equipment.