Tests and Analysis of Loop Type Long-Flashover Arrester

This paper presents analysis of operation of the loop type long-flashover arrester (LFA) working as overvoltage protection of medium voltage overhead lines with covered conductors. In this research the LFA was tested in the laboratory with standard lightning impulse voltages. The resulted sparks were registered with fast camera and the results were compared with spark development predicted with numerical simulations. This paper also presents developed relation between breakdown voltage of loop type long-flashover arrester and the arrester distance to power line wire. That relationship helps to coordinate insulation level of both LFA and insulation of protected line.