Analytical study on prevention methods for distribution arrester outages caused by winter lightning

The effectiveness of lightning protection methods, such as lowering the grounding resistance and reducing the installation interval of surge arresters, for preventing damage to arresters on power distribution lines caused by direct lightning strokes in winter is investigated. Furthermore, several countermeasures for arrester outages which occur in spite of the installation of an overhead ground wire are studied quantitatively. The main results are as follows: (1) the installation of an additional overhead ground wire is more effective in preventing damage to arresters caused by winter lightning than increasing the withstand capability of arresters, by a factor of two; (2) and lowering the grounding resistance of arresters to 30 /spl Omega/ is not effective in reducing the number of arrester outages.