Lead Acid Batteries Modeling and Performance Analysis of BESS in Distributed Generation

Acknowledgement I would like to acknowledge my thesis supervisor, Dr. Greg Crebbin for providing guidance and for helping me to define my research topic, constantly asking me the tough questions. Authors, who have made past contribution to this topic of research and in turn, helped me to formulate my own thesis understanding. Finally, to my family and friends who have provided much needed moral support at a difficult and challenging time of my life. Completing my thesis is for you. Abstract In this thesis, a methodology to accurately determine the state of charge (SOC) of a lead acid battery is proposed by calculating the integration of the net current flow through the battery at given time, t. Using an electrical circuit diagram of the lead-acid battery model; will run a simulated model of a lead acid battery and its charging or discharging characteristics are estimated based on the input values provided by manufacturers' or user specifications. Using the data found, an optimum state of charge (SOC) was determined and a battery energy storage system (BESS) was sized accordingly. A simulation of a peak load scenario was conducted and a system performance analysis was carried out on the BESS connected to a micro-grid system. An investigation into the transient voltage stability at a peak load condition was conducted to compare the response of the battery bank and a diesel powered generator in ability to cope with increase in the load demand. Furthermore, an investigation into four types of control strategies for a distributed generation system was proposed with some predicted outcomes analyzed. It was found that operating the BESS as a secondary control mechanism to a primary diesel generator was the optimum control setup. Further investigation into the levelized cost of energy (COE) would be required to conclusively determine these findings.