DC electric field simulation of a disconnector is of important significance for optimizing and checking its structure

shortening product development period

reducing costs of development

and guiding development of the product.In the design process of a 1 120 kV DC disconnector

the authors analyze the effects of the fracture distance

the grading ring tube radius at moving and fixed sides

and the shielding ring tube radius at moving side on the field strength of the disconnector in order to speed up the research and development and to facilitate the design of grading rings.It is concluded that when the grading ring tube radius is 200 mm and the shielding ring tube radius is 150 mm

the electric field strength of the disconnector at the place of grading ring is less than 3 kV/mm with good electric field shield and without breakdown of fracture or breakdown to earth.