Effect of Cylindrical Function on Measurment of Space Charge Distribution in Coaxial Cable Insulator using PEA Method

When the space charge distribution in coaxial cable insulator is measured using pulsed electric-acoustic (PEA) method, it is necessary to consider the cable geometry such as inner and outer radii. In PEA method, amplitude of acoustic waves generated by applied pulse voltage depends on the pulse electric field distribution which is not constant in the cable insulator. Furtheremore, since the generated acoustic waves radiate from the generated positions, the amplitude of the signal acoustic wave depends on the propagation distance to the detecting piezo sensor. Therefore, the effect of electric field distribution in cable insulator and distance of propagation must be considerd. However, the signal obtained from the cable insulator measurement is usually processed as same as the signal of plate sample. In this paper, difference between the space charge distribution obtained with and without considering a cylindrical function are simulated in the various geometry of cable insulator.