COORDINATED PROTECTION OF LOW-VOLTAGE DC DISTRIBUTION SYSTEM BASED ON THE FRONT ZONE BRAKING COEFFICIENT

With the continuous integration of renewable energy into the power system, low-voltage DC distribution systems have received increasing attention. Low-voltage DC distribution system has the advantages of high energy conversion efficiency and high-power quality. However, the complex fault characteristics of low-voltage DC distribution systems and the existence of distributed energy sources make it difficult to apply traditional AC protection methods directly. Therefore, this paper proposes a coordinated protection scheme based on the front zone braking coefficient, which realizes fast fault detection and accurate positioning by judging the range of the front zone braking coefficient and combining the fault differential characteristics. The simulation analysis and results show that it can significantly improve the reliability and stability of low-voltage DC distribution systems.