A Probabilistic Approach for Secondary Arc Risk Assessment

A probabilistic methodology for secondary arc extinction time calculations is presented. The proposed approach permits the calculation of the probability of secondary arc extinction as a function of time and represents an extension of the well-known deterministic model proposed in [1], where the extinction time is obtained from EMTP-type simulations and groups of secondary arc reignition voltage curves. Instead of using only one pessimistic characteristic, a probability distribution is evaluated to randomly select the reignition voltage curve to use for each calculation. As opposed to the deterministic methods, the proposed probabilistic approach allows the assessment of the risk undertaken by a power system under different single-pole reclosing time schemes and distinct weather conditions alike.