The most often type of damage in electrical networks with the voltage 6-35 kilovolt are single-phase closings on earth (SCOE), which make for around 75% of the total damages. The majority of such closings have a arc-like character. Overvoltages, thermal effects of the grounding arcs that ground, lead to the development of SCOE into interphase short circuits and multiple closings.
        An effective way of preventing breakdowns in the result of SCOE is a compensation of capacitive current of the network with the help of arc-suppressing reactors (ASR). Protective action of ASR, tuned in resonance with the capacity of the network, shows itself in the following way:
        - in the place of closing current is reduced to the level of an active component and higher harmonics;
        - apart from that the thermal effect and ionizing ability of the grounding arc are considerably reduced, also its resistance and probability of extinguishing rise;
        - the speed of current resumption on the damaged phase after extinguishing of the arc is reduced, which enables renewal of dielectrical power of the damaged isolation;
        - the levels of overvoltages are reduced on the damaged phases;
        - the conditions of electrical safety of the personnel are improved;
         The topic of the master’s work is connected with the scientific work of the chair - Н-26-05.
        -The aim of the work -

       Improving the system of automatic control of arc-suppressing reactor with magnetic bias.
        -The tasks of the work-

         1. To work out the system of differential equations that describes the regulator, based on the phase principle for defining the degree of tuning of the arc-suppressing reactor with magnetic bias in the mode of closing on earth.
         2. To make up a mathematical model of the electric network with arc-suppressing reactor with magnetic bias for the analysis of stationary and transitional processes with the phase closing on earth.
         3. To make calculations on the EOM? model of electrical network with the automatic regulator in different conditions.
         4. To work out the method of improving the effectiveness of the arc-suppressing reactor with magnetic bias and make up a functional scheme of the device that puts the proposed method to practice.
         -Practical significance of the acquired results -

The results of the work were reported at All-Ukrainian scientific technical conference, held in Sevastopol in April 2008. On the results of the work the theses of the report were published. The scientific work on the modeling of arc-suppressing reactor with magnetic bias is accepted for participation in the competition of students’ scientific works on electrical engineering.
         -Approbation of the work-

The results of the work were reported at All-Ukrainian scientific technical conference, held in Sevastopol in April 2008. On the results of the work the theses of the report were published. The scientific work on the modeling of arc-suppressing reactor with magnetic bias is accepted for participation in the competition of students’ scientific works on electrical engineering. The defense of the work will take place at the end of April 2008.
         -Literatura-

        1 Лихачев А.П. Инструкция по выбору установки и эксплатации дугогасящих катушек, 1971 г. - 104с.
        2 Обабков В.К., Обабкова Н.Е. Теоретические и экспериментальные исследования возможностей создания автокомпенсатора емкостных токов на основе дугогасящего реактора с подмагничиванием // Электрические станции, 2001. – № 10.
        3 Миронов И.А., Кричко В.А., «Автоматические устройства настройки компенсации емкостного тока замыкания на землю в сетях 6-35 кВ», ЭЛЕКТРО-ИНФО, №4,
        4 Брянцев А.М., Лурье А.И., Долгополов А.Г. и др. – Управляемые подмагничиванием ДР с автоматической компенсацией емкостного тока замыкания на землю для сетей 6 – 35 кВ, - Электричество, - №7. – 2000. – с. 59 – 67\
        5 Патент РФ №2222857, МПК7 Н02J3/18, опубл. 2004.01.27
        6 Правила устройства электроустановок. — М.: Энергоатомиздат, 1986.
        7 «Типовая инструкция по компенсации емкостного тока замыкания на землю в электрических сетях 6-35 кВ» (ТИ 34-70-070-87), СПО Союзтехэнерго, Москва, 1988г.
        8 Долгополов А.Г. Системы автоматической настройки компенсации для дугогасящих реакторов, управляемых подмагничиванием. — Электротехника, 1999, № 11. йки компенсации для дугогасящих реакторов, управляемых подмагничиванием. — Электротехника, 1999, № 11.