S.K. Sheryazov, A.V. Pyatkov
South Ural State Agrarian University, pr. Lenina, 75, Chelyabinsk, 454080, Russian Federation
Abstract. The development of the agro-industrial complex is accompanied by an increase in the consumed electric energy. Under these conditions, it is important to increase the efficiency of electricity supply to agricultural consumers. Electricity in rural areas is supplied by distribution grids, in which there are a large number of 6-10/0.4 kV step-down transformers. In the course of the study, the electric load on the 10/ 0.4 kV transformer bus-bars was monitored to assess the effect of non-linear load on power losses. As a result of the experiment, the presence of an asymmetric non-linear load that is significantly different from each other on the side of the high and low voltage of the power transformer was revealed. The study confirms the adequacy of the proposed methodology for the calculation of the power loss caused by the nonlinear load and allowed us to estimate the expected power loss according to the monitoring data. Analysis of the data shows that higher current harmonics additionally cause power losses in the transformer windings, and the volume of them can be about 15%. In this case, the calculation must be performed for each phase on both the higher side and the low voltage side. In transformers, the loss of power from the action of higher harmonic current components is expected more in low voltage windings. It accounts for more than 2/3 of the total loss of power and should be expected to accelerate the aging of the insulation in this winding. Under these conditions, the reliability and efficiency of electricity supply to agricultural consumers is reduced.
Keywords: agro-industrial complex; agricultural consumers; efficiency of electricity supply; rural electrical networks; asymmetric nonlinear load; power losses in transformers.
Author Details: S.K. Sheryazov, D. Sc. (Tech.), prof. (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); A.V. Pyatkov, applicant.
For citation: Sheryazov S.K., Pyatkov A.V. Power Losses in Transformers Caused by Non-Linear Loads of Rural Consumers. Dostizheniya nauki i tekhniki APK. 2017. Vol. 31. No. 11. Pp. 72-74 (in Russ.).