Electrical Field Distribution and Safety Evaluation of Mobile High Voltage Combined Electrical Equipment

Abstract

The structure of electrical elements in mobile high voltage combined electrical equipment is more compact compared with that of conventional substations. Accordingly, its electrical field intensity may increase, which even exceeds the standard value. In this paper, the electrical field intensity distribution of the mobile high voltage combined electrical equipment was calculated by using the finite element software Ansoft Maxwell. The electrical field intensities of two different parts were evaluated, namely the ground and the plane which is 1.5m above ground. Results show that the maximum electrical field intensity appears at the connection zone between lead-in bushing and metallic fittings, which reaches 21.11kV/cm. The maximum value of ground electrical field intensity is 1.55kV/m, while the maximum electrical field intensity of the 1.5m above ground plane is 11.94kV/m. The electrical field intensity of the 1.5m above ground plane exceeds safety margin, which can be decreased within limit by setting a 1m railing.