172 / 2024-04-15 15:42:12

Study on on-line measurement method of surface charge for HVDC GIL insulator

HVDC GIL,surface charge accumulation,online measurement,Insulation

Surface charge accumulation on insulators is one of the key factors limiting the large-scale application of HVDC GIL, dynamic on-line measurement of surface charge can help reveal the charge accumulation mechanism and propose charge suppression methods. In this paper, a new method for surface charge online measurement of DC GIL insulator is proposed, that is, ring-shaped multipoint potential method (RMP). The effectiveness of RMP method is verified by experiments, a corresponding experimental platform is built, and typical discharge defects are set up inside the GIL chamber. After that, the surface charge distribution results obtained by RMP method are compared with that obtained by traditional point-by-point scanning method. The results show that: After surface charge accumulated on the insulator, the potential at ring-shaped measuring points will change significantly, and the change can be accurately captured by active electrostatic probe. Furthermore, the surface charge inversion results based on RMP method are basically consistent with those obtained by traditional methods in terms of amplitude and distribution characteristics. The RMP method can effectively restore the surface charge distribution on nearly 2/3 area of insulator surface, which can help locate the area with serious surface charge accumulation. This study can provide a reference for the surface charge online measurement technology of DC GIL insulators.