الفهرس | Only 14 pages are availabe for public view |
Abstract The three-phase Split-Source Inverter (SSI), which was recently proposed as a single-stage DC-AC converter with the capability of either voltage bucking or boosting, is considered in this thesis for the photovoltaic applications. The SSI utilizes a reduced passive element count compared with the ZSI, in addition to a diode for each inverter leg. The SSI has two modes of operation L-charging mode and L-discharging mode. Moreover, it provides a promising solution for transformerless grid-connected photovoltaic (PV) systems. This thesis presents a comprehensive performance analysis and implementation of the three-phase Split-source inverter. The output results are verified in the laboratory to ensure that the finished design is simulated by using Matlab/Sim-power system. Besides, this thesis introduces a comprehensive study to assess the performance of three different power converter configurations for three-phase transformerless Photovoltaic systems. The first configuration is based on the standard two-stage dc-dc-ac converter, which is composed of a dc-boost converter followed by a three-phase voltage source inverter (VSI). On the other hand, the second and third configurations are single-stage converters that are based on quasi Z-source Inverters (qZSIs), and Split-source Inverters (SSIs), respectively. This thesis analyzes the performance of the presented topologies and compares them in terms of the topology requirements, modulation techniques, and output voltage control for both ideal cases and considering the resistance of the inductors. On the other hand, the closed-loop control of the SSI in grid connected operating mode was addressed, and a decoupled control scheme was introduced to independently control the SSI dc and ac sides, which is convenient for many applications. This control scheme is based on a combination of the proposed RMSV modulation scheme and the commonly used synchronous reference frame control technique. The SSI dc side was modeled first and then the introduced control scheme was discussed. The effect of a three-phase Split-source inverter has been extensively studied. Moreover, the effect of circuit non-idealities on performance has been investigated. The attained theoretical relations have been checked using both simulation and experimental results for static loads. A laboratory system has been implemented based on the DSP board of the Define F28379D Launchpad Kit controller board. Different modulation techniques have been applied. |