Investigation of the Influence of Unbalances the Single-Phase Ground Fault Current in a Coal Mining Enterprise

This article presents the results of research on the stability of the functioning of protection against single-phase ground faults of distribution networks of mining enterprises. Based on the analysis of the results obtained, it was found that in conditions of high heterogeneity of the network configuration, the current protections do not allow providing the necessary sensitivity and selectivity of the damaged connection. During research, it was found that the single-phase ground fault current contains unbalances. The causes of the occurrence of unbalances are identified, possible numerical values are determined and a method for debugging protection against unbalances is developed. The efficiency of the developed algorithm was confirmed by simulation modeling results. An experiment was conducted to reduce insulation in the distribution network of JSC «Polosukhinskaya», according to the consequence of which the revealed values of capacitive currents allowed us to determine the operability of the approach of detuning from imbalances.