Local electric field analysis for evaluation of charge transfer system using sequential subwindow technique

This paper presents an accurate analysis of electric field for charge transfer system (CTS) that was recently developed to reduce the likelihood of lightning strikes to premises. Since a CTS has many sharp metal points, its geometric modeling is very difficult. To calculate accurately the electric field of CTS, we propose sequential subwindow technique that analyzes local electric field in a small region compared with the size of the total system. The electric fields of brushes and of the top area are calculated and compared with the results of a Franklin rod. A bipolar air terminal that consists of a CTS and floating conductor is also analyzed by the subwindow technique. Experimental lightning tests of CTS and the bipolar air terminal are conducted, and the results show usefulness of the subwindow technique.