الفهرس 
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Abstract
This thesis presented a proposed design of non-communication protective schemes suggested solving the problem of communication with the capability to detected and isolate the faulty parts. The proposed protection schemes aimed to enhance a Future Renewable Electric Delivery and Management (FREEDM) system. The presence of distributed generation units in smart distribution gridschanges the power flow in thesegrids to a bi-directional flow which causes miss coordination of conventional protection schemes. Hence,thisthesis proposed a new protective scheme based on a microcontroller (Arduino Uno) to the FREEDM system namedbackup protection unit. The backup unit consists of three major schemes, (overcurrent, over/under voltage and differential relays). The backup protection unit proposed in chapter 2, depends on designing time inverse directional overcurrent protection and optimizing the coordination between relays to obtain the minimum isolation delay time. The proposed technique is validated by ETAP software. Three types of relays are designed in Chapters 3-5. The designed relayes are based on microcontroller Arduino UNO devices. The first one is an over-current protection relay which is located on the branch link the medium voltage distribution bus with solid state transformer (SSTS). A special program is designed using Proteus software package and integrated to the hardware card. To validate the proposed relay, the inverse, very inverse and extremely inverse overcurrent relay characteristics are tested using the proposed system simulator and compared with the characteristics recorded by the well know IEC 60255-151 standard. To guarantee the effectiveness of the proposed protection scheme a practical circuit including the proposed relay is implemented and connected to a small motor and. The results validate the curves of IEC correctly with reasonable percentage errors. The second proposed relay is based on Arduino UNOcontroller which is an over/under voltage relay and is located on the link between SST and medium voltage distribution bus. The relay senses the voltage by a potential transformer located across of the medium voltage link and feeds the microcontroller through a rectification bridge. A C-code including the three steps of over-and-under voltage settings is built up. The three steps are instantaneous, momentary and temporary ones. The controller monitors the values of the voltage and pre-set the values according to the IEEE standard and detects whether these valuesviolate the standard. The scheme is simulated and tested by Proteus software package and the results are compared with the values of the IEEE standard. A practical model of the proposed scheme is built in the lab with the temporary class. The results prove the ”prove the accuracy and precision of the designed program. The third proposed schemeincludes the design of a novel percentage differential protection relay to protect the medium voltage distribution cable connecting the terminals that ended by (FID) fault isolated devices. The proposed scheme successively protects theselected part of the closed loop bus connecting the FREEDM with solid state substation transformer.A practical module is built up and implemented whereas the operation of the relay is simulated by a developedC program. The simulation is done using Proteus software package. The simulation and experimental resultsconfirm that the proposed protection scheme is accurate and trustable.