Influence of Void Dimensions on Partial Discharge in Solid Insulation

In order to analyze and evaluate the danger of partial discharge of void defect discharge in solid insulator,this paper establishes a model of common void defect discharge in solid insulation,and investigates development and pulse waveform of discharge in void with different dimensions.It is found that discharge characteristics of defects are different each other,and discharge rules under different electric field are concluded,and void partial discharges in solid insulation have similar waveform characteristics.However,when the void dimension becomes larger,special discharge pulse waveforms appear.Analysis indicates that the larger void defect dimension is,the easier discharge appears.Once discharge occurs,discharge quantity is closely linked with void dimension,which is in direct proportion with discharge quantity.Electric field can also affect discharge quantity,which is in direct proportion with electric field at the beginning,after applied electric field lasting for several minutes,they seem to be in inverse proportion.Discharge pulse waveforms in voids with different dimensions possess different characters.