Влияние динамических свойств ОПН на ограничение перенапряжений в распределительных сетях

One of the most efficient means of over-voltage reduction in arcing ground short-circuits is an application of   a nonlinear over-voltage limiter. It is necessary to take into account dynamic properties of the nonlinear over-voltage limiter in order to ensure authentic simulation of  over-voltage in the network A dynamic model of  the non-linear over-voltage limiter which takes a time lag constant   τ  into account during transition of the nonlinear over-voltage limiter into conducting state has been developed in the paper.Одним из наиболее эффективных средств снижения перенапряжений при дуговых замыканиях на землю является применение ОПН. Для  достоверного моделирования перенапряжений в сети необходимо учитывать динамические свойства ОПН. Разработана динамическая модель ОПН, которая учитывает постоянную времени запаздывания τ, при переходе ОПН в проводящее состояние

Technical and Economic Assessment of Choosing Location of Step-Down Transformer Substation

The paper considers a problem concerning existing methods for  choosing location of a step-down transformer substation (STS). Algorithms and program segments for calculation of STS location using  existing and CG methods have been developed in the paper. The paper presents results of investigations numerically and graphically and it also contains an assessment of the CG method efficiency

NONLINEAR OVERVOLTAGE LIMITER APPLICATION FOR INTERNAL OVER-VOLTAGE PROTECTION IN AVERAGE VOLTAGE NETWORKS

Review of internal over-voltages in distribution networks 6…10 kV and means of their limitation has been carried out. One of the most efficient remedy for reduction of over-voltage at arcing ground is resistive neutral grounding. In order to estimate an influence of a nonlinear over-voltage limiter (NOL) on over-voltage reduction at ground an experimental research of varistor characteristics with 2,4 and 3,8 kHz frequencies has been carried out.Parameters of the NOL dynamic model have been determined. The main peculiar feature of the model is an account of m-lag time constant.A mathematical modeling of transitional processes in distribution networks with NOL has been made.Over-voltages in the calculative experiment at arcing ground for load diagram have accounted for 3.2 Uf, that corresponds to the results of field tests

Influence of Dynamic Properties of Nonlinear Over-Voltage Limiter on Over-Voltage Limitation in Distribution Networks

One of the most efficient means of over-voltage reduction in arcing ground short-circuits is an application of   a nonlinear over-voltage limiter. It is necessary to take into account dynamic properties of the nonlinear over-voltage limiter in order to ensure authentic simulation of  over-voltage in the network A dynamic model of  the non-linear over-voltage limiter which takes a time lag constant   τ  into account during transition of the nonlinear over-voltage limiter into conducting state has been developed in the paper

РЕФЕРАТЫ Технико-экономическое обоснование выбора места расположения понижающей трансформаторной подстанции

The paper considers a problem concerning existing methods for  choosing location of a step-down transformer substation (STS). Algorithms and program segments for calculation of STS location using  existing and CG methods have been developed in the paper. The paper presents results of investigations numerically and graphically and it also contains an assessment of the CG method efficiency.Рассмотрен вопрос о существующих методах определения местоположения понижающей трансформаторной подстанции ПТП. Составлены алгоритмы и программные фрагменты для расчета местоположения ПТП существующими методами, а также методом сопряженных градиентов. Приведены результаты исследований в численном и графическом виде, оценка эффективности метода сопряженных градиентов