Microgrid: Challenges and Progress in Recent Years

The global push toward decarbonized and resilient power systems has revived deep interest in microgrids (MGs) — localized grids that can operate either connected to the main utility or in autonomous islanded mode. This paper reviews the challenges and significant progress in microgrid technology over the past several years, focusing on architectures, power converter topologies, control and energy management strategies, communication technologies, and protection schemes. Drawing from peer-reviewed literature published between 2019 and 2024, this review identifies persistent gaps such as stability under high renewable penetration, cybersecurity vulnerabilities, and the need for standardized protection frameworks, while also documenting the rapid advances driven by artificial intelligence, IoT integration, and smart grid convergence. The paper is intended as a reference for researchers, engineers, and students working in the field of distributed energy systems. Keywords: Microgrid, Renewable Energy Integration, Distributed Energy Resources, Power Converter, Droop Control, IoT, Energy Management System, Smart Grid, Islanded Operation