Partial discharge（PD）is the important index of insulation conditions in electrical equipment

and the distribution of electric field in electrical equipment is closely related to the generation of partial discharge. In recent years

the research on the distribution of electric field in the bus room

cable room

handcart room

and circuit breaker inside a switchgear

have attracted widespread attention and already acquired important research results.However

there are few investigations on electric field distribution of load switch inside a switchgear. In this paper

the electric field distribution of load switch is obtained by using electrostatic field analysis with the software

Ansys

and some relatively concerned areas of the electric field have been observed. In addition

the position which is vulnerable to partial discharge in the interior of a load switch is verified by the actual operating status of equipment

and those research conclusions are the basis of theory of the partial discharge monitoring. Considering the humidity of the ambient environment

this paper changes the relative dielectric constant of environment

and the relevant change rules of electric field intensity in the surface of outgoing line ends are found out

based on which

installing a dehumidifier inside a switchgear as an effective measure for suppressing partial discharge is proposed. What’s more

the whole electric field simulation results have important guidance significance for the structure design and optimization of load switch inside the same type semi-insulating switchgear.