Výměna elektrických ochran v teplárně na rozvodně 6 kV

Abstract

This diploma thesis deals with the issue of replacement of electrical protections at 6 kV substation in a heating plant as part of its reconstruction. It is about a new calculation of the parameter settings of the new electrical protections, which will replace the old existing protections. The reconstruction will also replace the old switchboard cabinets with new ones and the primary voltage level will increase from 6 kV to 22 kV on the side of the electrical supplier. The diploma thesis is divided into two main parts – the theoretical part and the practical part. The theoretical part describes generally the issue of protection. It also deals with the analysis of electrical short-circuits and the calculation of short-circuit currents. Then the substation and its individual fields are also described. The end of this part describes the protections which are designed for the new substation. The practical part consists of calculations of short-circuit conditions of the substation and its parts for the new setting of new protections. The last part will deal with the evaluation of the proposed setting of new protections based on calculations.