A new index for the assessment of power system strength considering reactive power injection and interaction of inverter based resources

Abstract

Power system strength evaluation is vital to maintain secure operation in power systems having huge dependence on Inverter Based Resources. This paper reviews the state-of-the-art power system strength assessment methodologies along with their research gaps. Further, this paper proposes a novel power system strength assessment index for power system strength assessment in the presence of Static Var Compensator. A modified IEEE 39 bus system with Inverter Based Resources was used for the validation. The proposed index is validated in positive sequence modelling software using voltage stability margin and is compared with existing indices. To verify the applicability of the proposed index along with other existing indices, Electro Magnetic Transient type simulations are presented, which illustrate the sensitivity of the voltage following a three phase to ground fault followed by transmission line tripping in the power system.