Influence of Extreme Environmental and Deep-Sea Temperature Conditions on Silicone Oil Used for Insulating Underwater Electrical Switching Systems

Abstract

Abstract This study focuses on understanding the influence of extreme environmental conditions on silicone oil applied as an insulating material in underwater electrical switching systems. The extreme environmental conditions imply adverse operating temperatures of the underwater electrical systems which must be effectively handled by the silicone oil. For this purpose, a standard high voltage (HV) relay is selected and is immersed in a silicone oil thereby enhancing its operating voltage to 20 kV. First, the geometry of the modified relay switch is captured and converted into a CAD model. Subsequently, the developed CAD model is imported into the simulation software and converted into a numerical model and subjected to AC/DC, electrostatic and stationary case simulation. The adverse temperature conditions are varied i.e., from −50 °C, 0 °C, 20 °C, 40 °C and 120 °C respectively. The potential and electric field displacement at the electrodes of the high voltage relay is recorded and analyzed. Following this, high voltage experiments are carried out on an actual high voltage relay constructed based on the simulation model and the respective parameters such as discharges. Thus, the dielectric quality of the silicone oil under wide range of temperature is studied. The simulation and experimental results obtained altogether validate the design modifications made on the standard relay converted to meet the high voltage requirements of underwater electrical switching systems. Once this is identified, the chosen relay is compared with the experimental findings to validate the design modification.