الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Voltage source inverter (VSI) is commonly the core power of inverters employed in various industrial applications. However, it has a drawback of limited voltage because of bucking capability. The evolution of renewable energy sources especially PV and fuel cell applications as an alternative source of energy instead of conventional energy resources has attracted the attention to develop new power converters enhanced with boosting capability of input DC voltage and grid integration systems. Moreover, it must have the ability of power inversion from DC to AC and vice-versa to deliver and control the renewable harvested power to the grid. Therefore, adding these features to the conventional VSI by inserting another stage of DC-DC converter must be implemented before the DC/AC inversion stage. The new stage uses active and passive circuit components in addition to buck/boost the input DC link of the inverter bridge. This type of converters is widely known as two-stage converters and can be divided into two main types: • Isolated two-stage converters. • Non-isolated two-stage converters Nevertheless, of the significant robust performance of the two-stage converters, inserting extra stage with extra active and passive components increases system complexity, losses, cost, and footprint size. Accordingly, single-stage inverters were introduced, offering better features compared to two-stage converters such as current source inverter, Z-Source inverter, boost inverter and buck-boost inverter were presented as a single-stage converter with bucking/boosting voltage capability and DC/AC inversion without adding any extra switches and with relatively simpler control strategies and implementations. In this thesis, Three-phase two-leg buck-boost inverter with DPP unit is proposed as a new inverter topology with a lot of advantages like that lower voltage stresses on switches related to DPP unit with simple control strategy, generates a pure sine wave output with larger than input DC voltage without need for passive filters and lower THD compared to VSI. These privileges will decrease cost, size, and implementation setup. A MATLAB/SIMULINK® simulation comparative study is approved for various control techniques of proposed inverter topology to validate the performance of inverter in different operating conditions. The proposed inverter is experimentally validated using a laboratory setup to a rough simulation study.