Transient Protection of UHV Busbars Based on Standardized VMD-Shannon Entropy

Transient bus protection exhibits ultra-high-speed action, yet displays low reliability under weak fault conditions. This paper proposes a novel multidimensional fault analysis framework to address this issue. By investigating the propagation characteristics of transient high-frequency components of fault traveling waves in a 3/2 bus system, a transient protection method using composite characteristics consisting of four fault features is developed, of which two Shannon entropies have increasing properties and one entropy difference has decreasing properties. This dual-dimensional approach minimizes misclassification. Additionally, standardized fault characteristics representation ensures robustness across diverse conditions, which differentiate 36.1% of cross-partial fault characterization data, while also resolving 33.5% of false activations and 11.1% of rejected activations. Finally, EMTP-RV is utilized to validate the accuracy of the proposed algorithm in identifying bus faults and out-of-area faults for a wide variety of scenarios including fault initial angles, fault resistances and fault types, as well as in correctly distinguishing between bus I faults and bus II faults through numerous simulations.