Investigations on Screw Connectors for XLPE~1 Insulated High-Voltage Cables with the Help of a FEM~2 Simulation Program

摘要

This paper deals with the investigation of screw connectors for XLPE-insulated high-voltage cables. Due to the increasing demand for energy, especially in urban agglomerations, it is necessary to transfer large amounts of electrical energy. For this purpose, it is essential to use large cross-section conductors which leads to the use of large screw connectors. Therefore, it is needed to investigate the transfer behaviour of existing connectors and to incorporate this knowledge into the development of larger connectors. The investigations are based on the Rule of Donati. In addition, an ideal connector without contact screws is simulated and evaluated by means of FEM simulation program. The results are used as a basis for comparison. Subsequently, the simulation results of an existing screw connector are examined and evaluated on the basis of the previously created evaluation. In addition, the simulation results are checked for their correlation by means of practical (mechanical) tests on the original connector. Finally, the results and the efficiency are presented and questioned using the previously defined "ideal connector". First results showed that surface contact of the conductors is decisive for current commutation as expected. In particular, the transmission behaviour of RSC (Round Stranded Compacted) aluminium conductors in a screw connector are investigated. For this purpose, further mechanical tests were carried out and compared with two-dimensional simulations of an RSC conductor in a connector. The expected result is to determine how a RSC conductor behaves in contrast to a SC (Single-Core) conductor in a standard connector in order to detect targeted optimization measures. This is intended to drastically reduce both production and assembly costs as well as losses inside the connector. It is necessary to continue research on the basis of these investigations. In particular, the transmission behaviour in the case of direct current, as part of the energy transition in Germany, needs to be examined in more detail.