Application of the train congestion recovery method for constructing an instantaneous direct current railway section

Improving the energy efficiency of the transportation process is one of the key tasks, the solution of which is one of the priority areas of the holding JSC «RZD» research. The successful solution of this problem depends, among other things, on the effectiveness of measures taken to reduce energy losses arising from electricity transmission to the consumer, which is the rolling stock of electrified railways. To develop a set of organizational and technical measures aimed at minimizing electricity consumption, an effective apparatus that provides determination of energy losses amount of in the electric-traction netware in real time is needed. The article proposes a method for hardware-analytical calculation of energy losses, which is based on an algorithm for processing the results of direct measurements. It is proposed to calculate power losses using laws and relationships known from the course of electrical engineering. A distinctive feature of the proposed method is the function of recreating the instantaneous circuit based on the data of currents and voltages measurements at the control points of a given section. The proposed method is suitable for use exclusively on DC electrified railways. Also, the paper presents the methods for determining energy losses used today in Russia, and gives their brief characteristics. The logical and mathematical apparatus of the method is described in detail, indicating the possible reasons that, in the process of synthesizing instantaneous circuits, can affect the occurrence of errors. An assessment of the study results of this method application in the electric-traction netware of railways is given.

Voltage Unbalance, Power Factor and Losses Optimization in Electrified Railways Using an Electronic Balancer

Unbalanced currents, low power factor and high losses contribute to increasing the bill infrastructure managers must pay to the TSO/DSO operator that supplies electric energy to the railway system. Additionally, if regenerative energy coming from braking regimes is not allowed to be injected into the grid or even is penalized when it occurs, then the optimization of those parameters must be pursued. One of the possible measures that can be taken to counteract those phenomena is the installation of electronic balancers in heavy loaded substations in order to optimize the interface to the three-phase electric grid. This paper shows the benefit of such use taking examples from real conditions and realistic simulations assumed equivalent to field measurements.

Determination of Electromagnetic Influence of 25 kV AC Electric Traction Network on 10 kV High-Voltage Overhead Line

Electrified railways include a system of cable and overhead lines. An analysis of the operation of alternating current (AC) electrified railways sections shows that the value of the induced voltage caused by the operation of the traction network can significantly exceed the permissible level on adjacent disconnected high-voltage overhead lines. As a consequence, this leads to serious injuries to operating personnel, including deaths, failure of electrical equipment. From this point of view, 1x25 kV 50 Hz AC railway system networks are considered the most dangerous. The electromagnetic influence of the traction network of a double-track section of an AC railway on an adjacent 10 kV high-voltage overhead line for power supply of automatic block signalling is investigated in the offered paper. Emergency cases of traction network operation are considered: short-circuit situation and forced state. The calculations of short-circuit currents in the influencing inter-substation zone, as well as estimation of the induced voltage on the wires of the 10 kV disconnected high-voltage overhead line for various schemes of grounding, have been performed. The investigations were carried out on models built using the ATP-EMTP program.

Hydrogen electrified railways based shunt hybrid filter

<p><span id="docs-internal-guid-6cf44f0d-7fff-feb9-1fb3-a0d35695a54e"><span>This paper presents a proposal to keep the conventional railway system, by creating a secure external independent hydrogen station, with the integration of a parallel hybrid filter to isolate the propagation of harmonics, and the reduction of the current ripple. In modern applicactions hydrogen stations are one of the most important sources of sustainable energy; this has been considered one of the most significant sources of energy, as it has no pollution output. Most current research proposes to integrate the fuel cell into the railway, and this will make it face higher risks such as accidents and vibrations as well as the approach of the storage a system to different people. We research any aspect of the proposed method and we demonstrate the ffect of shunt hybrid filter (SHPF) uses in stopping the propagation of the harmonics to the hydrogen side.</span></span></p>

Improving the Efficiency of High-Speed AC Contact Suspension

When developing a high-speed contact suspension for railways electrified with alternating current, it is important to ensure that the electric rolling stock passes the neutral insert without turning off the current and without reducing the speed of movement. The article provides an analysis of previously developed devices in the field of power supply of electrified railways of single-phase alternating current, in which an attempt was made to pass an electric rolling stock of a neutral insert without disconnecting the load. The device of isolating coupling of a catenary and a neutral insert for high-speed railway lines electrified on alternating current is described. In this case, the passage of the neutral insert is carried out under current and braking of the electric rolling stock will not occur. Among other things, to improve the efficiency of high-speed contact suspension for railways electrified with alternating current, it is proposed to use new materials and new technologies that can be used in the device of insulating coupling of the catenary