Transient response of nuclear power plant cables to high-altitude nuclear electromagnetic pulse (EMP)

Abstract

The electromagnetic pulse (EMP) produced by a high-altitude nuclear detonation consists of a transient pulse of high intensity electromagnetic fields. These intense fields induce current and voltage transients in electrical conductors. Although nuclear power plant cables are not directly exposed to these fields, attenuated fields will couple some EMP energy to these cables. In the study described, theoretical and experimental techniques have been used to determine the EMP surges induced in several types of cables typically used in nuclear plants. It was found that unshielded lines such as power cables within the plant building may have EMP surge peaks as high as 88 kV induced between the cables and the earth. Shielded cables such as coaxial cables will have EMP surge peaks in the tens of volts. Cables located in electromagnetically tight conduit will have only small EMP-induced transients on the order of several millivolts or less.