10:00 AM on Wednesday, November 18, 2009
Location: 457 Whittemore

Master of Science Thesis Defense for Wencong Su

Committee Members:
Virgilio Centeno, Co-Chair
Yilu Liu, Co-Chair
Richard Conners, Member

Abstract:
As distributed generations and renewable energy are becoming the fastest growing segment of the energy industry, the technical issues and environmental impacts have to be taken care. It is challenging due to the large number of small-scale Microgrid components with their own characteristics. The main goal of this thesis is to build a library of various Microgrid components. Firstly, a detailed of description of Microgrid models with moderate complexity is presented in this thesis. The modeling of loads, utility grid and transmission lines is briefly covered. Distributed generation models have been developed in Matlab/Simulink including Diesel Engine, Fuel Cell, Micro Gas Turbine, Wind Turbine, Photovoltaic Cell. Also the detailed modeling of short-term storage (Battery, Pumped Hydro Storage, Flywheel, and Supercapacitor) are presented. In addition to steady-state study, the hybrid sample systems are built to investigate their transient responses. To enhance the simulation performance, some improvements on modeling and simulation are introduced as well. To accommodate the high demand of renewable energy and the environment policy, the planning and operation of Micro-source generators is studied using HOMER. Analysis of the results for several cases on Ontario area show the optimal configuration as well as the effect of uncertainty. Also demand side management plays an important role in the operation of Microgrid. Based on raw data, case studies are carried out to investigate and validate the demand response methods. Finally, the philosophy for Microgrid protection, especially Time-delay overcurrent protection, is introduced in both gird-connected and islanding modes.

Contact: wencong(at)vt( dot )edu