Theses and Dissertations

Issuing Body

Mississippi State University


Ginn, Herbert L., III

Committee Member

Fu, Yong

Committee Member

Follett, Randolph

Committee Member

Srivastava, Anurag K.

Date of Degree


Document Type

Dissertation - Open Access


Electrical Engineering

Degree Name

Doctor of Philosophy


James Worth Bagley College of Engineering


Department of Electrical and Computer Engineering


The ever increasing demand for electricity has driven society toward the installation of new generation facilities. Concerns such as high costs associated with installation of new facilities, environmental pollution, higher transmission and distribution losses, depleting fossil fuels has created a lot of interest in exploring the renewable energy sources for generation, particularly near the load sites. Accordingly, emphasis has been put on Wind, and Photovoltaic (PV) energy systems. A study on the operational characteristics of these systems reveals that the power generation is high at certain optimal points and recognizing these optimum points and operating the system accordingly is an interesting and important part of the system design. Further, a hybrid Wind- PV system has higher reliability and generation capability when compared to either source alone, and as a result many such hybrid systems with an additional energy storage backup for increased reliability have been proposed. While the systems with energy storage are reported to have satisfactory performance, the energy storage component is typically found to incur the highest cost, requiring frequent maintenance and hence acts as a deterrent for increasing the renewable energy generation. Particularly, for small grid connected applications like shopping malls, office buildings, etc. any additional power that could not be provided by the hybrid system could be provided by the grid, and in case the power generation is higher it could be sent to the grid. For cases like this, it would be ideal if systems could be developed without energy storage, and maximum possible power could be extracted from the hybrid energy sources. Also, the power quality concerns posed due to the random nature of the power generated from the hybrid system, is an important issue that must be addressed. The conventional control methods used typically require overly sized component ratings, resulting in the degradation of the dynamic performance while adding to the cost of the system. This dissertation addresses these issues by proposing faster maximum power extraction algorithms from the hybrid renewable energy system, and proposes new control architecture for improving the output power quality to the grid.