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The work is devoted to the development of a control system for a wind generator with the use of a switched reluctance motor. The search for new structures for the construction of the power unit and control system of electromechanical systems of wind power complexes is an urgent task of today. The most common construction options for such systems include double-fed induction motors and permanent magnet synchronous generators. In the first case there is no possibility of full control of the flow of power transmitted to the network, and in the second case the main disadvantage is the high cost of such an electric machine, which is explained by the use of rare earth materials in its design. The use of a switched reluctance motor as a generator has significant differences compared to similar use of electric machines based on torque generation due to the Lorentz force. A mathematical model of the electromechanical system of a wind generator with a switched reluctance motor in the Matlab / Simulink environment was developed. It was shown by mathematical modeling that when changing the sign of load torque, the machine does not go into braking mode independently, as is the case with other electric machines. This creates considerable difficulties in the operation of such a system, since the transition to brake mode requires a change in control effects on the switched reluctance motor. Features of functioning of the switched reluctance motor in the mode of regenerative braking have been stated. The limits of change of control angles which allow to receive the maximum amount of the generated electric energy and reduction of pulsations of brake torque of the machine have been defined. The structure of the control system of a switched reluctance motor has been developed, which involves the use of a modified speed controller, which divides its output signal into a sign function, which is subsequently used to select the converter control angles, as well as the absolute value used in the operation of the modulation algorithm of the required current magnitude.

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The urgency of developing the system of automated control of energy flows in conditions of underground mining of iron ore has been shown. The principles of implementing of mentioned approaches based on the use of fuzzy logic have been proposed using previously defined criteria and algorithms of fuzzy control. The simulating of operation of fuzzy controllers in the environment of the MatLab software package has been carried out using two-part and three-part electricity tariffs. The efficiency of fuzzy controlling systems in conditions of single-channel and multi-channel controlling has been proved. The results of the application of various automated fuzzy control strategies in conditions of mining enterprises with underground mining of iron ore using two-rate and three-rate electricity tariffs have been analyzed. Corresponding recommendations for the optimizing of industrial energy consumption have been proposed. References 12, figures 8, tables 4.

Purpose is to develop a unified mathematical model to assess energy efficiency of a water inflow-drainage process as the real variant of stochastic method for water pumping from underground workings of iron-ore mines. Methods. The research process was based upon the methods of probability theory as well as stochastic modelling methods. The stochastic function integration has been reduced to summation of its ordinates and further transition to a proper boundary. Findings. A mathematical model of a water inflow-drainage system as a stochastic process has been developed in terms of input parameters of a standard operating iron-ore mine. The abovementioned has made it possible to assess realistically, substantiate, and obtain possibilities for a specific production facility as well as for generalization of the results involving determination of stochastic characteristics of drainage process. Originality. For the first time, a mathematical model of drainage from underground levels of iron-ore mines has been developed as a stochastic process. The process characteristics have been identified relying upon randomness of a water pumping technique. In contrast to the available settings, the new model parameters characterize their dispersion. Possibility to obtain complete characteristics of energy consumption has been obtained: for drainage; for water accumulation volume in underground water collectors; for water pumping from the specified mine depths over the specific period as random processes. A number of drainage features have been analyzed and differentiated being determined with the help of nor-mal law of water accumulation velocity in the underground water collectors in iron-ore mines. Practical implications. In terms of operating iron-ore mine, a generalized drainage mathematical model has been developed as a stochastic process using statistical data concerning water accumulation velocity in the underground water collectors. It has been proved that if the ordinates of water accumulation velocity in the underground water collectors obey the normal distribution law then it is expedient to characterize drainage as a stochastic process. The developed methods, studying drain-age as a stochastic process, help expand the research boundaries involving other auxiliary operations performed during underground mining of iron ore raw materials.

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