Nonlinear dielectric properties of polyimide in high AC electric field

The nonlinear dielectric properties of polyimide (PI) films, excited by high-intensity, AC electric fields, have been measured. This work highlights that DC conduction is a component the conductivity and loss response when surpassing certain threshold field strength. An additional Poole–Frenkel polarization, induced high-frequency also contributes to nonlinearity. increases losses through charge de-trapping process, so-called “jacking-up” effect. A novel expression captures large signal behavior complex permittivity introduced using Cole–Cole format. Finally, it shown power dissipation density in PI films remain fully linear frequency-independent up an E PF ∼100 V rms / μm more conservatively below X ∼ 45 V/ (i.e., end ohmic region). Consequently, polyimide-based insulated electronic devices are designed continuously operate this (including both uniform fringe fields) will immune frequency-dependent electrical aging. Their lifetime should not be affected any way.