| Authors |
Hee-Kyung Shin ; Jae-Suk Lee |
| DOI |
http://dx.doi.org/10.5207/JIEIE.2015.29.4.116 |
| Keywords |
Lightning Surge ; Surge Protective Device ; Coordinated SPD Systems ; Energy Sharing ; Voltage Protection Level |
| Abstract |
This paper presents experimental results obtained from actual installation conditions of surge protective devices (SPDs), with the aim of understanding the coordination of cascaded Class I and Class II SPDs. This paper also proposes effective methods for selecting and installing coordinating cascaded SPDs. The residual voltage of each SPD and the energy sharing of an upstream Class Itested SPD and a downstream Class II tested SPD were measured using a 10/350 μs current wave. In coordinating a cascaded voltage-limiting SPD system, it was found that energy coordination can be achieved as long as the downstream SPD is a metal oxide varistor with a higher maximum continuous operating voltage than the upstream SPD; however, it is not the optimal condition for the voltage protection level. If the varistor voltage of the downstream SPD is equal to or lower than that of the upstream SPD, the precise voltage protection level is obtained. However, this may cause serious problems with regard to energy sharing. The coordination for energy sharing and voltage protection level is fairly achieved when the cascaded SPD system consists of two voltage-limiting SPDs separated by 3 m and with the same varistor voltage. |