Conduction and space charge theories in dielectrics under
direct voltage conditions are reviewed and analysed.
Published information on gas discharge processes in insulation,
conductivity, discharge detection and measuring methods are also
A combined technique whereby both discharges and current can
be studied simultaneously is employed in the investigation of non-ohmic
conduction in solid dielectrics at moderate d.c. stresses.
Experimental evidence suggests that none of the conventional
laws of conduction adequately explains the observed phenomena e.g.
the thickness dependence of conductivity; and that the operating
stress 'E' calculated as the ratio of the externally applied voltage
to the thickness of the dielectric may not be the actual resultant
Some anomalies are explained on the basis of a new dielectric
equivalent circuit, a modified Maxwellian 'n' strata dielectric and
induced interfacial or space charges.
The discharge behaviour of gaseous voids in dielectrics is
analysed using an equivalent circuit incorporating the resistivity of
the void gas. Extinction is explained partly by an extended
Maxwellian polarisation phenomena....
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.