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The paper studies the optimization features of low-voltage electrical network modes for energy-efficient power transmission. The main features of these networks are the high values of the zero-sequence voltage unbalance factor and the mismatch of voltage values with the necessary requirements. Therefore, balancing the loads by phases and reactive power compensation are chosen as measures to improve the listed network parameters. One of the main factors for the effective solution of this problem is the determination of load balancing points and reactive power compensation, as well as the required power of the devices used. To solve the multicriteria problem of determining device connection points, an analysis of existing objective functions is carried out. As a result, a target function is proposed that includes costs, voltage losses, zero-sequence voltage asymmetry coefficient. When solving the optimization problem with the help of the proposed objective function, the voltage values and the voltage asymmetry factor at the consumer connection points will be within the required limits. The results of a study of the optimization function using the example of a model network are presented. The calculations are carried out in two stages: the search for sensor's nodes, then their study for optimality. All calculations are carried out in the MATLAB environment, taking into account voltage losses and power.

The paper presents the method local distribution of reactive power compensation in rural networks 0,4 kV for improve one’s of the main quality indicators electricity - steady voltage deviation and coefficient’s of voltage unbalance on the reverse and zero sequence. The calculated values reduce active power losses while improving the quality of electricity listed.

The paper presents the feasibility study of the transverse reactive power compensation in village distribution networks of 0,4 kV with a low power factor. Also presents the method for determining the position of compensating devices and their power to ensure the of set distortion of voltage corresponding to the norms of power quality and minimum reactive power factor for the consumer interconnection points to the electrical network 10 (6)-0,4 kV cos ф=0,944.

The distribution networks of the most widespread network loop circuit - closed network, open at one of its nodes. This disconnection point must be selected according to the criterion of minimization the active power losses, electric power and ensure the reliability of power supply. Definition of a rational point for breaking the overhead network, corresponding to the minimum active power losses, is quite a tedious task. In practice, therefore, this point is taken randomly, which leads to considerable losses of active power and voltage. Currently, there are no methods for determining the point of breaking for meshed networks of 10 kV overhead, taking into account the power loss in the lines and the actual value of the voltage, which results in an incorrect definition of the point of rupture. The method of determining the optimum point of breaking meshed network of 10 kV is developed. It is ensuring minimal loss of active power. The validity of the proposed method was checked by the example of several typical 10 kV networks.

The article deals with the discovery of femtosecond signals of self-diffraction and photon echo in a zinc oxide film of 100 nm thickness, consisting of different-sized quantum dots, at room temperature. Experimental results, proving the Autler-Townes effect demonstration on exciton transitions of quantum dots, are obtained.