Simulating dielectric breakdown based on Maxwell’s equations with inhomogeneous conductivity

Dielectric breakdown of electrical insulations under high-voltage conditions can cause damage to electronics and electrical equipment, resulting in property losses. To investigate the breakdown behaviour of dielectric polymers, a simulation method of dielectric breakdown is proposed in this paper. A maximum electric field intensity criterion was integrated with Maxwell’s equations. A Gaussian distribution function was coupled with the criterion to illustrate the stochasticity of the breakdown strength. A damage factor was proposed to differentiate the intact and breakdown material, whose local properties were modified according to the damage factor. Maxwell’s equations that have considered the inhomogeneous material properties were solved using the finite element method in the time domain. The tree-like breakdown channels were obtained by the proposed method. The method brings a novel insight into the study of the degradation and breakdown mechanism of dielectric materials.