Identifikace a lokalizace zemního spojení v sítích IT/500V

Abstract

Operation of isolated neutral system in the industrial environment brings many benefits in terms of supply network reliability, minimizing of downtime, safety and protection against dangerous contacts of electrically active parts. On the other hand it is necessary to solve some problems caused by the operation of these networks, especially type of failures such as the earth and the intermittent earth fault. Industrial ambient conditions negatively affect the quality of insulation of electrical equipment. For example, in the section of rolling mill the devices are affected by water, abrupt temperature changes, metal dust and other contaminants. These effects lead to the degradation of material of the insulation, to the deterioration of the insulating condition of electrical devices and to the increase of the frequency of the failures in the form of the earth fault. The task of the thesis is to test the currently available devices designed for monitoring and localization of the earth fault occurred in the isolated neutral system which is used in the industrial environment. For this purpose a network model will be created. The model will enable various settings for the simulation of the conditions of the real network. Based on the result of the measurement and testing the application of the monitoring and the localization of the earth fault will be created. The application could be utilized within the industrial isolated neutral system of the low voltage. This application falling into the field of the preventive and predictive maintenance will enable a significant reduction in the maintenance time after the failure.