Innovative mitigation measures for electrostatic charge build-up on surfaces of dry-type air-core reactors for HVDC application

Abstract

Equipment installed in the d.c. yards of HVDC converter stations is subject to the electrostatic charge build-up phenomenon. This can result in pollution accumulation on the surfaces of the high voltage equipment operating at high d.c. potential. The charge build-up on the reactor surface may cause discharges across the surface and through the encapsulation of the winding packages. In case of dry-type air-core HVDC reactors the observed pollution build-up takes the form of an irregular pattern of varying sized black spots.