الفهرس | Only 14 pages are availabe for public view |
Abstract In the past few decades, the high demand for clean energy and the increased proliferation of renewable energy resources has gained significant attention worldwide. The integration of both renewable and conventional distributed energy resources (DERs) such as photoreactive (PVs), wind turbines, fuel cells, micro-turbines, and energy storage systems has developed the idea of microgrids. Microgrids have become an important researchable topic due to the increased need for the utilization of distributed generation sources recently as microgrids are considered the most economical solution for the usage of distributed generation sources without demolishing non-renewable ones. The main obstacle that faces the spread of microgrids is the need to improve the conventional protection systems especially for fault detection and location algorithms to cope with many challenges resulting from the integration of DERs and the different topologies of the microgrid. This thesis aims to introduce a complete protection algorithm that can overcome all microgrid operational issues, firstly by introducing a fault location algorithm suitable for multi-voltage level microgrids using a unified set of equations, then to introduce a complete protection algorithm. The proposed fault location algorithm is combined with a previously introduced fault detection scheme. The proposed algorithm depends on constructing the bus impedance matrix between the fault point and the nearest bus using the measurements of micro phasor measurement unit (Micro PMUs) located at end buses of the faulted line. The proposed complete protection algorithm can accurately detect and locate different types of faults in both islanded and grid-connected modes. Finally, the proposed algorithm is tested using MATLAB and ETAP software for symmetrical and asymmetrical faults in multi-level microgrids and found effective in different microgrid modes, errors in fault location didn’t exceed 1% under any circumstances. |