Probabilistic Adequacy and Transient Stability Analysis for Planning of Fault-initiated Islanding Distribution Networks

Fault-initiated islanding can significantly improve the reliability of power supply in distribution networks, by allowing (parts of) distribution networks to operate as islanded microgrids in case of a contingency. The probability of generation adequacy and transient stability of these microgrids has to be critically evaluated during planning of fault-initiated islanding, in order to compare the incurred reliability and cost. The analysis of the probability of transient stability is challenging, as it generally requires a very large set of detailed time-domain simulations to be performed. Stability during the fault-initiated islanding transient has therefore not been considered during probabilistic analysis in the literature. Additionally, the beneficial properties for the value of fault-initiated islanding have not yet been identified. To address these issues, a methodology for probabilistic adequacy and transient stability analysis with a low computational burden is proposed in this paper, and used for rigorous sensitivity analysis of a modified fault-initiated islanding RBTS Bus 2 benchmark distribution network. The results show that the probabilistic adequacy and transient stability analysis methodology is accurate with a relatively low computational burden, and that fault-initiated islanding is most valuable in networks with a controllable and total generation capacity of at least 14.7% and 58.9% of the average load power respectively, moderate to high fault probability, and medium to high load cost.