High-Resistance Grounded Power-System Equivalent Circuit Damage at the Line–Ground Fault Location—Part I

This paper provides an electrical equivalent circuit of a high-resistance grounded (HRG) power supply transformer to discuss damage at a fault location so long as the fault remains a line-ground fault. Fault resistance and fault current that have an effect on damage are included in the equivalent circuit. Three-line diagrams showing fault current flows along with their vector diagrams are also included. Part II of this paper provides a similar equivalent circuit for an HRG grounded generator. This paper provides guidance to update the current edition of IEEE STD. 142 with respect to HRG systems.