Proposal of the reconstruction of the distribution network in a specific area

This diploma thesis is concerned with reconstruction of distribution network in Hruba Vrbka. The diploma thesis is divided in two parts. For better understanding to this issue, the first theoretical part is shortly dedicated to the history of electrical power system, to the several types of distribution network of low voltage and high voltage and their utilization in the area, considering the reliability and the quality of delivery of the electric energy. In this thesis there is mentioned division of distribution grids according to placing of cable lines, according to voltage and according to type of grid connection. Next part of this work is dedicated to the description of overhead lines and cable lines and their characteristics. For the proper concept of the grid we should know some characteristics of the electric line’s proposal: mechanical strength, warming, voltage drop, efficiency, degree of safety and provision of delivery. In the end of the theoretical part there are described methods for calculation of grid’s steady state as a linear task and also non-linear task, elimination of the balancing node, the iterative method, the reduction of external power take-off nodes and the solution of the steady state of the network through the direct current model. The second part of the diploma thesis is concerned with the calculation of the steady state in the village Hruba Vrbka. In this part is also described the KASI program which was used for the calculation of the grid’s steady state. Firstly low voltage grid’s balance in Hruba Vrbka was found out and evaluated and then there were proposed some solutions of the reconstruction for the grid improving. The suggested options of the reconstruction are considered from technical and economical point of view and the best solution is chosen. For this solution there is suggested the protection through program SICHR 9. In the end of this diploma thesis there is checked the load of the high voltage line