The paper considers various compensating devices of power system network parameters. A special attention has been given to controlled flexible power lines and control over them.

The improved vector-parametrical and simplified methods for calculation of electro-dynamic stability parameters of flexible busbars in high voltage switch gears have been presented in the paper. The developed methods and their software can be taken as a basis of methodological instructions on calculation of short-circuit current electro-dynamic action on flexible conductors of switching gears.

The paper considers a problem pertaining to determination and qualitative evaluation of harmonic composition of typical voltage forms that supply an AC motor. Analytical expressions for determination of n-harmonic amplitude in regulation have been received and they can be used for simulation of  an AC motor operation.

The paper proposes a method for calculation of the technological electric power consumption for its transportation in the elements of power network while using block-stations under conditions of differently-directed electric power transfer.

The calculation of technological electric power consumption for its transportation can be applied while supplying several consumers with one element of power network simultaneously with block-station operation.

The paper considers problems concerning electromechanical interaction in elevators with an adjustable asynchronous electric drive equipped with the vector control systems under direct torque control and direct torque control with pulse-width modulator. A mathematical description of electromechanical elevator system with due account of nonlinearity of the worm gear is given in the paper. The paper presents a simplified circuit design of a control system with a fuzzy speed controller. It has been established that the factor of electromechanical interaction in electromechanical system with the adjustable asynchronous electric drive and an fuzzy speed controller is within the range which corresponds to existence of the essential electromechanical interaction.

The paper presents a new design of a blade untwisting device where blades are considered as a main element of the device. A profile of the blades corresponds to a circular arch. An inlet angle of  the blades is determined by stream aerodynamics in an exhaust pipe, and an exit angle is determined by rectilinear gas motion. Optimum geometrical parameters of the untwisting device have been determined and its application allows to reduce a pressure drop in the ЦН-15 cyclones by 28–30 % while screw-blade untwisting device recovers only 19–20 % of energy.

The paper considers an environmental influence on working high speed mill as a component of vortex heat pump. Experimental investigations of small high speed mill have been carried out in the aerator mode. The paper has determined conditions when the high speed mill is acting as a heat pump. It has been shown that the high speed mill has a maximum transformation ratio not more than 3.5.

The paper considers a possibility and justification to use gas systems for heating industrial buildings due to radiant heating.  Heating modes of heat systems are given in the paper.

A methodology and results of experimental pulsation investigations on products of underwater hydrogen-oxygen gas mixture explosion in cylindrical chambers which are open from the bottom and spherical chambers with elastic covers are provided in the paper. The paper contains a comparative analysis of experimental investigation results with theoretical calculations.

The paper considers problems concerning regulation of frequency and active power in regional power system under modern conditions. Methods of rational power station expense distribution while rendering system services on regulation of frequency and active power between all power stations of the power system.