The article presents classical mathematical models of electric arc characterised by undetermined or unreduced ignition voltage. The aforementioned models include the well-known Mayr and Cassie models and their well-known Schwartz extensions with the power functions of the Mayr and Cassie voltage as well as the increased dissipation of energy within the high-current range. The modified models contain residual conductance, enabling the determination of arc ignition voltage. A similar approach was applied to modify the approximating functions of voltage and current characteristics used in the Pentegov model. Computer simulations were used to examine the influence of the parameters of the mathematical models on the shapes of static and dynamic characteristics of arc located in a circuit with sinusoidal current excitation.

doi: 10.17729/ebis.2019.4/7