الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Power electronic system arc considered as one of the most important components at many applications, such as nuclear reactors. aerospace, military applications and life saving machines In such applications the system should be highly reliable, so that the reliability problem should be taken into account during the design and operation phases All possible faults which the machine can be subject to it should be studied and analyzed avoid its occurrence and to hurry the maintenance process The power electronic components (active and passive) can be destroyed due to many kinds of faults which reduce the equipment reliability level So monitoring and analysts of power electronic system under normal and fault conditions is very important to discriminate the type of fault and give the correct diagnosis of the fault In this thesis a three phase induction motor drive system was studied for normal operation and fault conditions, the system consists of three phase supply, diode bridge rectifier. DC link capacitor, an invoice and a three phase induction motor. the previous system was mudded and simulated at venous types of fault located at the supply utility, the diode rectifier The DC link, the invoice arid the induction motor by using MATlAb simulation package, and the simulation results was compared normal and fault conditions to achieve the fault detection rules These results were analyzed according to the following principles. Time domain. frequency, domain and the current space vector approach. A knowledge-based expert system was developed to diagnose faults in the proposed system by using a software tool called KAPPA PC 2.1, the simulation results at normal and fault conditions was rewritten as a set of(If- then) rules by which the expert system can discriminate the fault The capers system supports an interface environment between she system and the user during the fault finding process. The expert system has diagnosed some selected faults successfully and It has given good results