Protection Characteristics of Two-stage Cascaded Surge Protective Devices

초록

In this paper, when surges impinge at the service entrance of a building, the protection characteristics of two-stage cascade surge protective devices(SPDs) were investigated. The influence of the distance between the upstream and downstream SPDs on the energy coordination was analyzed experimentally. It was found that the energy sharing of two-stage cascaded SPDs strongly depends on the distance between the two-stage cascaded SPDs and the component of SPD. As the distance between the two cascaded SPDs increases, the energy absorbed by the upstream SPD increases, while the energy absorbed by the downstream SPD decreases. Consequently, it is desirable to select the upstream and downstream SPDs having the proper energy capability with due consideration of the distance between the two-stage cascaded SPDs.