Reliability of FGM bulb type spacer in three-phase gas insulated busduct with protrusion and depression defects under particle contamination

Electrical substations must operate reliably and effectively no matter the environment they are located in, and they must also repair damage fast. Due to a number of problems that occurred throughout the switching and manufacturing processes, including as delamination, protrusion, depression, gap, etc., spacer failures of the gas insulated busduct (GIB) have recently been discovered. These defects have a major negative effect on the spacer’s surface, which de-energises the gas-insulated busduct device and causes a large financial loss. For the purpose of studying the electric field stress at the triple junction, a functionally graded material (FGM) spacer is designed in this paper for a 3 phase GIB with particle along with protrusion and depression abnomalities. The stress is reduced by inserting metal inserts at the end of the enclosure. Functionally graded materials are spatially distributed with a variety of filler materials to achieve uniform electric field stress by doping them with various permittivity values. Simulation is carried out on a bulb type spacer in 3 phase gas insulated busduct with different voltages and FGM gradings. The impact of grading’s on electric field stress is studied and further reduced with the introduction of the metal insert (MI) to the FGM spacer. The simulated results with and without MI are discussed and analysed to demonstrate the viability of the proposed spacer.