A Non-Iterative Method Based on Fast Fourier Transform and Least Square for Fault Locating in DC Microgrids

One of the critical challenges in DC micro-grids is fault detection and location as quickly as possible. The DC buses could not withstand high fault current compared with the buses of AC networks. Also, determining the fault location will be very hard, if a fault results in complete power failure in DC buses. To do so, it is necessary to isolate the faulty sections. This paper presents a particle swarm optimization (PSO) based algorithm for this purpose and compares its results with the least-square based method for determining the fault location in DC micro-grids. This method utilizes a probe power unit (PPU) in DC micro-grids to determine the fault location. The distance of fault location from the PPU is a function of damping resonant frequency and attenuation constant. The damping resonant frequency of fault current is obtained by Fast Fourier Transform (FFT) and the attenuation constant is determined by the proposed PSO based algorithm.