Complex solution-phase earth fault in networks with isolated and resonantly neutral earthed

Abstract

Design and implementation of electrical networks 6-35 kV voltage control devices of outgoing lines with efficient al gorithms for determining damages, regardless of how structure and neutral grounding electrical Exploited also belongs to the priority areas of microprocessor systems protection from single phase to earth faults. Therefore, improving the re-liability of power systems considered only possible solution to the complex task of disaster earth fault and preventive measures to reduce the probability of their occurrence. In voltage 6-35 kV networks have proliferated many methods to determine the phase conductivities, according to which the selection algorithm of devices compensation capacitive currents. The most accurate method for metallic circuit used very rarely because of the complexity and dangerous effects on electrical equipment. Indirect methods significantly inferior in accuracy and reduces the essence of their application to the evaluation of capacitive current circuit for select-ing containers DGR.
To configure extinguishing all types of reactors and their diagnosis is specially designed portable device «Bres-ler 0107.065», which is widely used and recognition operations personnel. Controlled variables in any method of setting the GDR is the voltage on the neutral network. This voltage is measured by measuring the voltage across the terminals of the transformer windings, connected by an open triangle scheme. Difficulty handling this tension lies in its low (ideally zero) value in the normal mode of the network. For air networks to neutral voltage is mainly determined by the asym metry of the phase line relative to the ground. In cable lines asymmetry phases and the voltage was measured in tens
mV, and she is determined mainly by obstacles that are in the circuit zero sequence.
The following ways to configure the GDR: extreme, phase, frequency of natural oscillations circuit zero sequence.
Thus, the task of reducing accidents electrical networks with isolated neutral and compensated from single-phase earth fault is complex and involves taking measures to reduce the likelihood of faults, reducing losses from accident and identify the damaged equipment. To solve this problem, the methods of diagnosis and control parameters of isolation and extinguishing reactor, its settings. The method of setting compensation management, based on a comparison of the frequency of natural oscillations of zero sequence circuit electrical network frequency current industrial network, without drawbacks inherent phase and extreme regulators.