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The issue of increasing energy efficiency and energy saving is of great importance for the countries with high energy intensity of the gross domestic product, including Russia and the rest of the Commonwealth of Independent States. The measures adopted in Russia on the federal and regional level as part of the State Program on Energy Efficiency and Energy Development are focused on reducing the energy intensity of Russia's gross domestic product and introduce sustainable practices on energy saving in Russia's commercial and budget sectors. This paper presents a case study describing the way to reduce electric power losses in a system of power supply (SPS) of an industrial enterprise. In particular, the case study determines the level of the higher harmonic components of current and voltage at the existing enterprise for the production of reinforced concrete products. The results of the experiment were reproduced using a simulation model of the power supply system in the Matlab/Simulink package. A comparative analysis of using a passive and hybrid filter compensating device to reduce the level of the higher harmonics of current and voltage was carried out by means of modeling. The active losses in the SPS from non-sinusoidal mode are calculated. In addition, the economic effect of using the proposed method is estimated.

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The article presents an approach to the development of mathematical models of non-sinusoidal and dual-frequency power supply for a linear induction MHD machine for metallurgical purposes. The issues of construction and numerical modeling of the modes of a three-phase inductor for a liquid aluminum stirrer are considered. Reduction of losses is ensured by the use of a toothless design of the MHD inductor. The absence of steel teeth reduces saturation of the magnetic circuit and current distortion. It is proposed to use the parametric model of the inductor under the furnace in the ANSYS environment to clarify the modes of the complex. To take into account mutual induction, using controlled sources, a circuit model was built, and a numerical calculation of the modes was carried out. The characteristics of instantaneous currents and voltages are obtained when powered from a three-phase source with close frequencies, with pronounced beats. It is shown that the presence of mutual inductance redistributes currents in the delta windings, which must be taken into account when developing the design of linear induction machines. It is proposed to use sources with non-sinusoidal periodic currents in the modeling system. The analysis is carried out and the main types of modulated voltage characteristics in the power supply system of the induction MHD stirrer are shown.

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