送電線の直流残留電荷の減衰時間と漏洩機構の検討

Abstract

Authors once measured the decay time of residual dc charge in a 500kV transmisson line during five fine and dry days of winter season. The results showed a large scattering without depending on the simultaneously measured weather conditions, such as the measured time of a day, atmospheric temperature and relative humidity. Then the authors have performed an additional eriment in a laboratory to disuss the factors that affect the residual dc charge leakage focusing on the moisture in the air and the dusts floating in the atmosphere. It is shown that absolute humidity alone decides the decay time without scattering under clean and calm condition. The floating dusts blown up by the wind, however reduce the decay time and bring a large scattering. The dusts should be a charge carrier moving freely in the atmosphere.