The increasing integration of renewable energy sources, energy storage systems, power electronic converters, and flexible loads has made DC microgrids an attractive solution for efficient and reliable power distribution. However, the protection of DC microgrids remains challenging due to the absence of natural current zero-crossing, bidirectional power flow, variable fault-current characteristics, and the weak and changing fault currents associated with converter-interfaced distributed energy resources. These characteristics can lead to improper operation and coordination of conventional overcurrent protection schemes, potentially resulting in microgrid blackout. This work presents advanced protection schemes for the rapid fault detection and isolation in DC microgrids under both grid-connected and islanded operating conditions. The proposed approach utilizes local bus-voltage and line-current measurements to derive differential and complex-power-based protection indices. Real and imaginary power components obtained using fast fourier transform (FFT) are investigated for identifying pole-to-pole (P-P) and pole-to-ground (P-G) faults, while differential protection is employed to enhance the selectivity of DC bus-bar fault detection. Solid-state DC circuit breakers are considered for rapid fault isolation.