Дослідження роботи дистанційного захисту в розгалуженій секціонованій лінії 10 кВ

Abstract

The article investigates the parameters of setting up adjacent remote protections with remote start-up, taking into account the peculiarities of operating modes and operating conditions of partitioned branched distribution lines. The influence of parameters and modes of operation of such lines on the range of adjustment of settings on resistance and time of operation at the end of a zone of action and requirements to linearity of time characteristics that allows to define distances to a place of short circuit on operation time is defined. The results for setting up remote protections of partitioned lines with sources of distributed generation are obtained: the conditions for adjusting the protection settings for resistance to operation are determined taking into account the parameters of the partitioned lines and the limits of adjusting the settings for resistance to secondary values are determined. The conditions for adjusting the settings by the time of operation and the limits of the time of operation of protection for most lines are determined. For selective operation of protection at the selected settings on time of operation unambiguity of time characteristics at change of sizes of working currents of protection on condition of ten percent accuracy of work of protection on resistance of operation is provided. The conditions for ensuring the selective operation of adjacent protections in the selected range of settings by the time of operation, taking into account the ratio of resistances and the difference in the time of operation are determined. The initial time of protection protection is substantiated for debugging of protection on time of operation against operation of overvoltage limiters and against burnout of fusible insert of fuses of branches and unsoldering at short circuit directly behind the fuse. The use of modern microprocessor protection devices will ensure, on the one hand, the accuracy of the resistance, linear and unambiguous dependence of the operating time on the resistance of the short circuit at different levels of currents and voltages, etc., and on the other hand - ease of maintenance.