The article considers the solution of the problem of joint use of linear MHD machines of different types, due to the modernization of furnaces for the preparation of aluminum alloys. It is established that the features of the joint work of hybrid MHD complexes and thyristor regulators require the development of methods to improve the electromagnetic environment at metallurgical enterprises. Due to the heterogeneity of two-phase and three-phase loads with a large asymmetry of currents in phases, the quality of electricity in the workshop network may deteriorate. To improve the ecology of the network, when using transistor IGBT inverters and thyristor loads in the power supply system, diagnostic tools for the quality of electricity are proposed. The measured operating parameters of power consumption show that the combined connection of MHD machines of different types to a three-phase network overloaded with non-sinusoidal currents is advisable with effective suppression of higher harmonics, as well as under the condition of counteracting current asymmetry.

The purpose of the article is to analyze the efficiency of transformers at PS 35 kV and above in terms of power losses. The criteria of optimal operation of transformer substations with two or more transformers are given. The analysis of the quantitative composition of working transformers in the branches of JSC "DRSK" in winter and summer is carried out. Substations where the operating mode does not meet the criterion of optimality of power losses have been identified. An assessment of the possible economic effect of switching substations to single-transformer mode has been carried out.

Data on the characteristics and equations of operation of DC collector motors CDPT are given. Their advantages associated with simplicity and linearity of control, simple start-up and compactness are noted. Their main disadvantage is the presence of a collector-brush assembly of the KShU, which limits the resource and energy efficiency of the CDPT. The characteristics of the BDT brushless motor are described, which requires the use of a controller, but eliminates the disadvantages of the CDPT, including limiting the speed of rotation. The order of operation of the BPT and the controller is given, and their characteristic features are also noted.

A comparison of the existing equivalent equivalent circuits of an asynchronous motor is carried out. The analysis of their advantages and disadvantages is carried out. Formulas for calculating the basic values of currents and voltages are also derived. Substantiated proposals for the use of substitution circuits, depending on the modes of operation of the engine. Hypotheses have been put forward about the possibility of using equivalent circuits to identify the parameters of an induction motor.

Тhe formula of the transfer function for deformations of elastic-viscous bonds in a multi-mass multi-motor electric drive is obtained in operator form. Using the example of a frequency-controlled electric drive of a mine conveyor, a method for determining the transfer functions of deformations of sections of a closed traction chain is shown. A regulator for damping vibrations of deformations of elastic bonds of the conveyor has been synthesized.

The paper proposes the creation of a system for operational monitoring of the technical condition of overhead lines based on modular devices. The modular device is configured depending on the tasks to be solved: control of ice formation; control of ice melting; localization of the place of short circuit, breakage, lightning strike; determination of electrical loads on the wire or control of the load of transit overhead lines; determination of mechanical loads on the wire; determination of conditions for the occurrence of ice formation.

The energy indicators of an autonomous converter, criteria for assessing the quality of consumed electricity and distributed power supply systems are considered. DC/DC converters in the form of modular DAB converters are used for communication between different levels and buses of the above power supply systems. Steady-state and transient DAB modes are investigated. Simplified dynamic models of DAB and its individual modules are formed for the analysis of control systems by the averaged (linearized) DC component.