Analysis and Simulation Computations of Synthetic Test Current Distortion for High-voltage Circuit-breakers

During the current interruption process, the arc voltage across the contacts maintains a constant value in the high-current interval and increases to extinction peak value and then drops to zero with a very steep rate. There is a strong arc-circuit interaction between the arc voltage and the circuit of current source, which result in the prospective short-circuit current distorted as the current approaches zero. According to the annex A of international standard IEC62271-101, derivation of the distortion current expressions are presented in this paper with the constant arc voltage and linearly rising arc voltage respectively. With the influence of distortion current, it is complex to calculate the instant at the end of each current loop of short-circuit current and to use the distortion…