Analysis of HEM Parameter Identification Results Based on Experimental Data

The oil-paper insulation hybrid equivalent circuit model (Hybrid Equivalent Model, HEM) can effectively reflect the interior polarization of oil-paper insulation system, The parameters of the mixed equivalent model were identified by the remaining three groups of FDS test data with moisture content of 0.244%, 2.7% and 3.63%. For the test object of the same oil-paper insulation structure, the geometric capacitance C
g
is basically unchanged, the insulation resistance R
g
and polarization resistance will decrease with the slow increase of micro-water content of insulating paper, while the polarized capacitance will increase with the slow increase of micro-water content. At the same time, based on the above analysis, the characteristic parameters of HEM that are sensitive to the micro-water content of oil-impregnated insulating paper can be proposed: insulating resistance R
g
, maximum polarization resistance and minimum polarization capacitance of RC series polarization branch, maximum polarization resistance of interior polarization branch is shown in Fig. 1.