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Microgrids are integral to power grids; they enhance grid reliability by integrating distributed generators (DGs) to fulfill the local load requirements, lowering energy generation costs, and providing eco‐friendly energy resources to reduce carbon emissions. Despite their benefits, new capabilities also introduce protection‐related complexities, including bidirectional power flow, varying fault currents, false tripping, relay reach limitations, coordination issues, and the requirement for proper grounding. This article offers a detailed review of protection issues in AC, DC, and hybrid AC–DC microgrids, investigating existing approaches to address these issues. Furthermore, the constraints and hurdles associated with these approaches and the future trends and intelligent approaches required to develop a reliable and efficient protection strategy are also identified in this article. This article is categorized under:Energy and Power Systems > MicrogridsEnergy and Power Systems > Distributed Generation [ABSTRACT FROM AUTHOR]

Electronic band structure, optical and thermodynamic properties of ternary hydrides MBe[H.sub.3] (M = Li, Na, and K) were studied using ab initio density functional theory (DFT). The effect of the adopted approximation to the exchange-correlation functional of the DFT is explicitly investigated by considering four different expressions of two different classes (local-density approximation and generalized-gradient approximation). The calculated magnitude of B classifies MBe[H.sub.3] (M = Li, Na, and K) as easily compressible materials. The bonding interaction in these compounds is quite complicated. The interaction between M and Be[H.sub.6] is ionic and that between Be and H comprises both ionic and covalent characters. The electronic structure of the complex hydride was investigated by calculating the partial and total densities of states, and electron charge density distribution. Large gaps in the density of states appear at the Fermi energy of LiBe[H.sub.3], NaBe[H.sub.3], and KBe[H.sub.3] indicating that these classes of hydrides are insulators. Optical properties, including the dielectric function, reflectivity, and absorption coefficient, each as a function of photon energy, are calculated and show an optical anisotropy for LiBe[H.sub.3] and KBe[H.sub.3]. Through the quasi- harmonic Debye model, in which the phononic effects are considered, temperature dependence of volume V(T), bulk modulus B(T), and thermal expansion coefficient α(T), constant-volume and constant-pressure specific heat ([C.sub.v] and [C.sub.p]) and Debye temperature [ϴ.sub.D], the entropy S, and the Gruneisen parameter γ were calculated at wide pressure and temperature ranges. The principal aspect of the obtained results is the close similarity of MBe[H.sub.3] (M = Li, Na, and K) compounds. Key words: electronic structure, crystal structure, hydrides, thermodynamic properties, reflectivity, absorption coefficient. Nous utilisons la methode ab initio de la fonctionnelle de densite (DFT) pour etudier la structure des bandes electroniques et les proprietes optiques et thermodynamiques d'hydrides ternaires MBe[H.sub.3] (M = Li, Na et K). Nous etudions systematiquement l'effet de l'approximation adoptee pour la fonctionnelle DFT d'echange-correlation, en considerant quatre differentes expressions de deux classes differentes: l'approximation locale de densite et l'approximation de gradient generalise. La magnitude calculee de B classe ces hydrides parmi les materiaux compressibles. L'interaction de liaison dans ces composes est tres compliquee. L'interaction entre M et Be[H.sub.6] est ionique, alors qu'elle est partiellement ionique et partiellement covalente entre Be et H. La structure electronique est investiguee en calculant la densite partielle et totale d'etats et la distribution de densite de charge electronique. De larges bandes interdites (gaps) apparaissent a l'energie de Fermi pour les trois hydrides, ce qui les classe parmi les isolants. Les proprietes optiques, incluant la fonction dielectrique, la reflectivite et le coefficient d'absorption sont calculees en fonction de l'energie du photon et nous observons une anisotropie optique pour LiBe[H.sub.3] et KBe[H.sub.3]. Via le modele de Debye quasi-harmonique qui tient compte de l'effet des phonons, nous evaluons, sur de larges bandes de pression et de temperature, la dependance en temperature du volume V(T), du module de compressibilite volumique B(T) et du coefficient d'expansion thermique α(T) et calculons les capacites calorifiques a temperature et a pression constantes [C.sub.v] et [C.sub.p], la temperature de Debye [ϴ.sub.D], l'entropie S et le parametre γ de Gruneisen. De ce cote, ces trois hydrides sont similaires. [Traduit par la Redaction] Mots-cles : structure electronique, structure cristalline, hydrides, proprietes thermodynamiques, reflectivite, coefficient d'absorption., 1. Introduction It is widely believed that within a few decades hydrogen will become the fuel that powers portable devices and most vehicles, and will become the means of storing [...]