Process of sludge spraying on the constructional elements of the on-load regulator of a power transformer due to electroconvection

The process of sludge spraying on the constructional elements of an RNOA-like contactor of an on-load regulator is investigated. Calculation of the electric field in the contactor cavity filled with the dielectric liquid is performed. Areas of the largest voltage values of the electric field are determined. In these areas, the sludge particles are condensed due to electroconvection. It is shown that sludge spraying on the surfaces of various elements of the contactor leads to an increase of the electric field near these surfaces and increases the possibility of a breakdown in the isolation.