Investigating DC microgrids based on centralized protection: A case study of BTS

Abstract

This research presents an innovative protection strategy tailored for centralized DC microgrids specifically designed for base transceiver stations (BTS). The method leverages the similarity in the rate of current change measured simultaneously at both ends of a line segment to detect internal faults effectively. The approach addresses key challenges in microgrid protection including the detection of high-resistance faults, distinguishing between permanent and transient fault conditions, and safeguarding critical components such as loads, photovoltaic arrays, and batteries. It also considers the resilience of the system in the event of failures in line sensors and circuit breakers. Unlike conventional protection schemes that depend heavily on both voltage and current measurements, the proposed system offers a cost-efficient alternative. It operates with a single centralized intelligent electronic device (IED) overseeing the entire microgrid, complemented by only one current sensor installed at each end of every line segment. This streamlined configuration simplifies hardware requirements without compromising detection accuracy. The reliability and effectiveness of the protection mechanism have been rigorously validated through comprehensive simulations conducted in MATLAB/Simulink. The tests encompassed both internal faults within the microgrid and external fault scenarios, demonstrating robust performance under various operational conditions. This work contributes to advancing protection schemes for DC microgrids, which are increasingly pivotal for sustainable and efficient energy management in telecommunication infrastructure. It aligns with contemporary trends and challenges in microgrid protection, emphasizing economical design and dependable fault management.