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Based on the study of properties of an electric train as a control object, it has been proven that considerable speed fluctuations and shock loads caused by the presence of elasticity and gaps in the coupling devices take place during the train acceleration and stoppage. These loads cause current fluctuations in armature of the traction DС motors of electric locomotives, which adversely affects their service life. By studying the mathematical description of the dynamic system consisting of an electric locomotive and a set of wagons, a model was synthesized that allows one to investigate the processes taking place in this system when motion and coupling device parameters alter. On the basis of the mathematical dependencies obtained, an algorithm was developed that enables parametric optimization of the system from the point of view of minimizing collisions of the train wagons during acceleration and braking. A characteristic feature of the algorithm that distinguishes it from existing ones is that the "locomotive – wagons" complex is considered with taking into account presence of elastic coupler and gaps between the train elements. The problem of eliminating dynamic loads caused by oscillating processes of the "locomotive – wagons" complex was solved which made it possible to conduct an analytical construction of a system for optimal control of the material handling processes of electric transport in conditions of iron ore mines. Application of this system makes it possible to optimally perform high-speed loading of wagons with raw materials and their unloading. It is expected that application of this approach thru shortening the time spent in shifting the wagons for their loading will increase productivity of the mine transport by 20–30 %

Представлено результаты исследований проблемы энергооптимизации режимов рекуперативного торможения асинхронных частотно-регулируемых электроприводов транспортных средств. Доказано, что возможность реализации режима рекуперативного торможения зависит от величины угловой скорости. Определен механизм влияния параметров схемы замещения двигателя на эффективность реализации таких режимов. Предложена методика выбора тормозных моментов с точки зрения максимизации объема возвращенной электроэнергии

The research deals with analyzing peculiarities of using active rectifiers in frequency controlled electric drives of underground mine hoists. There are developed MATLAB models aimed at comparing two types of control systems – hysteresis-based and the one with pulse-width modulation. The research aims to analyze power modes and parameters of active rectifiers, quality of voltage control, current and power of active rectifiers and to determine ways of improving power indices of electric equipment of hoists as well as provide power compatibility of electric equipment and underground mines’ grids. Main attention is paid to analyzing circuitry of control systems of active rectifiers, parameters of power transformers and reactor equipment at underground mines’ substations, frequency converters and synchronous slow-speed motors. There are also analyzed statistic data on power consumption at underground mines equipped with automated systems of commercial and technical power meters and specific consumption of power. The research results reveal advantages of the pulse-width modulation control system as compared with the hysteresis one by using such indices as speed-performance, quality of control, potential of controlling reactive power and the power factor. Application of the research results will enable determining structures and methods of adjusting control over the active rectifier in the frequency-controlled drive of underground mine hoists.