A low-cost and efficient fault detection and location algorithm for LVDC microgrid

Abstract

Low voltage DC (LVDC) microgrids have many potential advantages for the electrification of rural developing areas. In the long term, these micro-grids could be interconnected to create local mini-grids, which would enhance resilience and power supply stability. Despite their advantages, effective protec­tion of these networks remains a challenge that is holding back their adoption. Thus, this paper presents a low-cost and efficient fault detection and location algorithm for the interconnection of LVDC microgrids. This algorithm is specially tailored for rural areas of difficult access in developing countries since it relies on inexpensive auxiliary devices. To be specific, the algorithm locates the fault by coordinating power converters and relays. It only uses relays and does not require extra high sampling rate sensors, which simplifies implementation and cost­effectiveness. The communication bandwidth is also very low. The algorithm can be effective for both low impedance and high impedance faults. In addition, it could be easily adaptive to different topologies. A DC network with ring structure is set up in Simulink to test the proposed algorithm. The simulation results shows the effectiveness of the proposed algorithm for low and high impedance faults.