Power Quality Improvement of Single-Phase Grid-Connected Photovoltaic Inverter By Trung-Kien Vu

Power Quality Improvement of Single-Phase Grid-Connected Photovoltaic Inverter By Trung-Kien Vu

A Dissertation for the Degree of Doctor of Philosophy

Department of Information and Communications Engineering
Graduate School
Chungnam National University


ABSTRACT The economical and environmental impacts of fossil fuels have forced society to investigate sustainable solutions. The interest has focused on the renewable energy sources since the green and clean benefits. Consequently, investments in research and development in the field of power electronics have increased proportionally, especially in high voltage and high power grid-connected systems. The distributed power generation (DG) systems are becoming more common as the need for electric power increases because of taking advantage of using different energy sources such as wind and solar. A few examples are hybrid cars, solar houses or hospitals in remote areas where providing clean, efficient and reliable electric power is critical to the loads. In such systems, the power is distributed from the source side to the load side via power electronic converters in the system. At low and medium power applications, the task is often left to single-phase inverters where they are the only interface between sources connected to dc bus and loads connected to an ac bus. This dissertation investigates the power quality improvements to properly regulate the power flow between renewable source and the utility network. The control method for single-phase inverters used in low and medium power DG systems is based on (and also takes the advantage of) the well-known d-q transformation (which is mostly employed for three-phase converters’ analysis and control design).