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In the article the possibilities of improving the adjustment properties and technical characteristics of electric rolling stock with collector traction motors are considered. Semiconductor devices can improve the smoothness of the traction motors start-up due to a more even voltage increase, smooth regulation of the field current in the traction and braking modes. Variants of simplified power circuits of eight-axis direct current electric locomotives with a minimum number of switching electrical devices have been developed, allowing to reduce weight and size of the equipment, increase the reliability of power circuits operations. Circuit solutions for protecting the wheelset of an electric locomotive from boxing and skidding by enhancing the traction motors field are considered. The role of semiconductor converters in the improvement of rolling stock with a combined and dual power is noted. The ways to improve the efficiency of electric braking by collector traction motors are listed. The necessity of using adaptive microprocessor control systems for semiconductor converters for expanding their functional capabilities and realizing optimal parameters of direct current rolling stock is noted.

The subject of the study is energy efficiency of traction power supply system and traction electric drive of electric locomotives. The article is scientifically based on the assessment of the energy efficiency of the mutually connected system of electric traction of trains. The study is aimed at solving problems on reduction of voltage losses in the contact system, active power in the contact system and traction electric drive of electric locomotives. This is possible due to the full and continuous use of the electrical potential of the power supply system. The research methodology is based on the law of energy preservation, mathematical modeling of the energy process and spectral analysis of voltage and current on the current collector of the electric locomotive. Analytically and by results of calculation it has been proved that significant losses of voltage, active power in the contact system, traction electric drive of electric locomotives are caused by unsatisfactory operation of power regulators and mismatch of voltage level in the contact power network, which is necessary for realization of heavy and high-speed driving of trains. In order to eliminate the negative effect of the inductive coupling of AC traction power supply on the energy efficiency and speed of trains, it is proposed to increase the voltage in the DC contact system and develop power regulators of electric locomotives. Mathematical model of DC electric traction system shows possibilities of reduction of electric energy losses and increase of movement speed due to application of electric semiconductor variator for matching of high voltage in contact system with voltage of traction electric motors of electric locomotive.

In this article, the object of the study is the power supply cables for non-traction railway consumers. The electrical parameters of the insulated conductor are determined. Primary parameters of the aluminum shell of the main power supply cable are obtained. As a result of solving the problem, the transient resistance of an isolated conductor is determined. From the boundary conditions, the propagation constant of the metal shell of the power supply cable in the polymer insulating coating is determined. As a result, the values of the transition resistance obtained by different methods are the same.

The paper presents a calculation of the magnetic field over the cable with damage. The cable with damage is replaced to equivalent circuit «conductor - shield». The conductor and the shield is considered as two single-wire lines, loaded on the characteristic impedance to avoid reflections. For this equivalent circuit defined sine wave signal change in the conductor and the cable shield. These results indicate that in cable fault location conductor current is significantly changed and shield current reaches the maximum value. The values of the shielding factor is determined at dif-ferent frequencies for the continuous tubular aluminum conductor and steel spiral conductor. The magnetic field is determined on the earth surface over the cable with metal shield having a «con-ductor - shield» damage taking into account the shielding factor. The results show that the module and phase of magnetic field is incremented in the cable fault location, which can be fixed on the earth surface. The results of calculation will improve the methods and hardware for cable fault lo-cation searching.

The article presents the equivalent circuit of three conductors, taking into account their mutual influence. The equivalent circuit contains the resistance and inductance of each conductor, the conductivity and the capacitance of their insulation relative to the earth, as well as the mutual inductances, conductivities and capacitances of the insulation between the conductors. The mathematical foundations of calculating the distribution of electrical quantities in the system of three conductors are considered, taking into account their mutual influence. An iterative incremental model of the software life cycle was chosen as the basis for automating this calculation, taking into account existing approaches to software development. Specific features of specialized software are specified. A structural scheme of the software complex and a block diagram of the calculation algorithm are proposed. The algorithm is based on the iterative calculation of currents and voltages for three conductors, taking into account their mutual influence. In accordance with the chosen model of the life cycle of the software, three versions of software with different functionality have been developed. This allowed us to effectively organize the processes of testing, debugging and implementation. As a result, the software complex has a window interface containing four tabs and allowing to enter the initial data for the calculation, display the results in the form of graphs and tables. For saving the results of calculations, a connection with the database has been implemented.

The article describes the design features of the current collection system of the Moscow monorail and revealed its shortcomings, limiting the possibility of increasing the speed of electric rolling stock. The features of a promising new generation of monorail transport system with increasing speed (up to 150 km / h), the message "city - the airport," which is proposed to use the contact current collection system with flat working surfaces of the current collector and the current lead. The aim of the work was to develop measures and technical solutions for improving the current collectors to provide reliable, cost-effective and environmentally-friendly electric power transmission on board the electric rolling monorail transport systems. The proposed technical solutions have allowed to increase the average life of the contact elements of the current collectors of electric rolling on the active sites of the Moscow monorail from 30 days to 5 months. A preliminary design and manufactured model sample collector rolling device for the new generation of monorail transport system with increased speed. A basic model of the pantograph, which allows to unify all the major components and spare parts for the current collectors of options for different speeds, load current, and other operating conditions and choose the appropriate model, taking into account technical and economic feasibility. The results can be used for the improvement of existing and development of new designs for current collectors of electric rolling monorail transport systems for the high speeds.

Article considers the analysis of working conditions of conductors of cars. Major harmful and adverse production factors inherent in this profession: vibration, noise, dust content, chemicals, adverse microbiological atmosphere. Work of conductors belongs to category of «travelling» pro-fessions, and, bigger number of conductors are occupied on long trips, moving during 3 and more (till 7 days). The incidence structure also has a number of differences: at conductors of cars diseas-es of respiratory organs, bodies of blood circulation, bone and muscular system, a trauma and al-lergic diseases prevail. Diseases of respiratory system at conductors make more than a half of all cases of temporary disability and meet mainly in the form of ORZ, rhinitises, bronchitis and pneu-monia that indicates the need of regulation and normalization of the air environment of the car which is object of long stay and a conductor workplace.