الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Modular multilevel converters (MMC) are high-voltage and high-power power electronics converters with high dependability, scalability, and reliability. The MMCs have found their way into many applications like HVDC power transmission, power quality improvement, medium voltage motor drives, and high-power renewable energy wind and PV farms.
Multiphase DC-DC converter represents a type of modular converter that could be scaled to provide high levels of power density. The performance of the maximum power point tracking system could be enhanced by utilizing the concept of decentralized systems, increasing the system’s reliability.
The recently introduced Split-Source Inverter (SSI) presents a better alternative to the well-known Z-source and Quasi Z-source inverters due to the lower number of passive elements and easier operation. The same PWM techniques of the conventional VSI can be used to control the SSI switches without needing an extra switching state.
This work proposes two systems of different structures for high-voltage, high-power photovoltaic applications. The first is a cascaded multiphase DC-DC converter with embedded energy storage that interfaces the PV panels and feeds the MMC to supply AC power. This system is of a two-stage configuration in which the power optimizer and the inverter are separated. The second structure is of a single-stage type. A new cascaded multilevel inverter topology is proposed in this work. This topology extends the idea of the SSI to the cascaded Multi-Level Inverter (MLI) configurations. The structure, operating principle, and modulation techniques are presented for the two systems. The validity of the proposed systems is investigated through simulation results. Furthermore, an experimental setup has been prepared for each converter and used to validate the applicability of the suggested systems.