Numerical analysis and application of electric field grading device for metal-enclosed switchgear

Electric field grading devices have great importance for both the electric power transmission and distribution systems. This paper presents an improved electric field grading device used in the medium voltage metal-enclosed switchgear. The solutions have been carried out by using Ansys Maxwell 3D software. The structure of two electrodes designed as cylindrical and elliptical have been compared to determine the electric field grading device to be used in practice. The transient and steady-state analyses have been performed in both designs. The field grading device manufactured for the metal-enclosed switchgear has been tested according to IEC standards in a high voltage laboratory environment. This study revealed that the newly designed field-grading device can be used in the metal-enclosed switchgear more safely. It also encourages researchers to optimize the electric field distribution using different geometric structures and to create running conditions in smaller indoor environments.