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Hybrid power supply systems (HPSSs) are considered as a good option for electric power supply of remotely located from the grid consumers due to significant fuel savings compared to diesel sets. Quick development and improvement of HPSSs may be achieved using specialized methodologies and programs. In the paper a schematic diagram is proposed and operation principles of a 400 V / 50 Hz HPSS were developed. The system’s main component is the master generating unit of the hydropower plant using a 250 kW induction generator (IG). The voltage of the system is controlled by the controller of the AC/DC power converter. The electrical frequency of the system is controlled by the speed controller of the hydropower turbine. A wind turbine, an energy storage system and a regulated dump load are connected to the IG through the AC/DC converter. Goal. The paper aims to develop a methodology for steady state performance analysis of the hydraulic turbine driven isolated IG operating in parallel through an AC/DC power converter with additional sources and consumers of active power. Methodology. The methodology for evaluation of performance characteristics of the IG operating in the proposed system has been developed. The methodology is based on the equivalent circuit of the system, equations of active and reactive power balance in the system and the superposition method. Results. The equations of frequency, voltage and power regulators of the system are given. The performance characteristics of the IG operating in the system supplying resistive and RL load in «constant voltage – constant frequency» mode are obtained. Novelty. The developed methodology is innovative in taking into account the control algorithms of the system. The comparative analysis of the IG’s performance operating in the stand-alone generating unit and in the generating unit connected to the proposed system is performed. Practical value. The developed methodology can be used for development and performance improvement of hybrid AC power systems.

Tools for computer investigation of the modes of operation of induction motors of the main circulating pumps of the VVER-1000 NPP reactor have been created. The mathematical model of the electrical engineering complex "synchronous turbogenerator of NPP unit – electric grid of power system – two transformers of own needs – four induction motors" in phase coordinates, oriented on explicit methods of numerical integration of the system of differential equations is developed. On the basis of the mathematical model the software designed for the study of electromagnetic and electromechanical processes of the system of induction motors of the main circulating pumps of the VVER-1000 nuclear reactor in the modes of: operative switching including start and run, switching to standby power, self-start of the motors with turbogenerator’s run-out and without it is developed. The investigations of the processes in the system of induction motors in the mode of operative switching during their power supply from the turbogenerator are carried out and the basic regularities of their course in qualitative and quantitative relations are established.

Purpose. The purpose of the article is to create dependencies of efficiency on effective power when changing the supply voltage and switching angles, pulsation speeds of the rotor from the moment of inertia of the drive and mechanical characteristics of switched-reluctance motors with a periodic load, developing recommendations to ensure their effective and reliable operating modes in single-cylinder piston compressors. Methodology. To carry out research simulation mathematic modeling was used, to calculate the nonlinear inductance dependence on current and rotor angle, the finite element method. Results. The measures of improve the efficiency and reliability of drives single-cylinder piston compressors on the basis of the SRM has been proposed. Originality. Approaches that provide maximum efficiency values and a regulated level of ripple speeds of rotors SRM of single-cylinder reciprocating compressors in the operating frequency control range, with periodic load have been developed. Practical value. Algorithm for changing the supply voltage and switching angles of the SRM of single-cylinder compressors, which provides maximum efficiency values SRM when the rotational speed changes within the 1:6 range, has been developed. The minimum values of the moments of inertia of the drive of single-cylinder compressors, providing a regulated level of pulsations of the rotational speed of the rotor SRM with its regulation, were determined.