Expanding the voltage control range of 6/0.4 kV power transformers

THE RELEVANCE of the study lies in ensuring high-quality electricity supply to consumers against the background of an increasing number of technological connections. One of the most important indicators of high-quality electricity supply is the voltage in electrical networks. The article considers the problems of voltage regulation in distribution networks (DN), which helps to ensure the required quality of electricity, reduce electricity losses and increase the capacity of power transmission lines.
THE PURPOSE. Development of measures to ensure the quality of electricity using various methods of voltage regulation.
METHODS of the study include mathematical modeling of power transmission lines (PL) taking into account the static characteristics of the load, as well as modeling of processes in distribution networks using automatic voltage regulation points (AVRP) and 10/0.4 transformers equipped with tap-changer devices for high-voltage windings without excitation (PBB) with an extended voltage regulation range of up to ±10%.
RESULTS. The results of the study demonstrate the feasibility of introducing transformers with extended voltage regulation limits.
CONCLUSION. The conducted study demonstrates that both of the considered methods, namely the installation of a PARN and the transition to transformers with an extended range of PBB of ±10%, make it possible to solve a key problem: maintaining the quality of electricity within the requirements at all nodes of an extended distribution network.

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