Abstract: With the advancement of the "Carbon Peak and Carbon Neutralization" strategy, distributed photovoltaic (PV) and energy storage systems have been widely integrated into low-voltage distribution networks, posing challenges to feeder operation in terms of protection coordination, protocol compatibility, and energy regulation. To address the issues of weak islanding protection, inconsistent protocols, and low multi-energy synergy efficiency in existing devices, this paper presents the development of an integrated device for "Four-Accessible" fusion of distributed energy resources. The device, based on edge computing and lightweight artificial intelligence algorithms, enables state perception, protocol self-adaptation, flexible power regulation, and intelligent islanding protection for distributed PV and energy storage systems. Significantly enhancing the safety, compatibility, and regulation capability of distributed energy systems, thereby providing effective technical support for intelligent access and optimized operation of distributed energy resources in low-voltage feeders.