Date of Completion


Embargo Period



Battery Energy Storage System

Major Advisor

Sung-Yeul Park

Associate Advisor

Krishna R. Pattipati

Associate Advisor

Ali M. Bazzi

Field of Study

Electrical Engineering


Doctor of Philosophy

Open Access

Campus Access


This dissertation discusses cost-effective sizing and optimal operation methods for battery energy storage system (BESS) that improve the reliability and stability of microgrid. In order to facilitate the implementation of BESS, Cogeneration plant with BESS is proposed. This methodology is comprised of four items to improve the efficiency and to reduce operation and maintenance cost.

In the first item, the generalized design requirements and needs are proposed through load and grid analysis. Through this step, an assessment of ancillary services is analyzed for determining BESS feasibility in terms of revenue. The discerned requirements for profitability are applied in the determination of BESS size and inverter capacity design.

In the second item, the optimal operation of BESS is proposed with PQ ratio control, load modeling and forecasting, and battery constraints. BESSs supporting grid stability and performance are investigated.

In the third item, contingent upon electrochemistry, the operational limitations of the battery system are determined and new charging methods for batteries are researched.

In the fourth item, allocation control scheme to maximize resource sharing of grid-connected inverters is proposed, especially BESS utilization. This dissertation focused on the allocation of reactive power because of the way of more economical power distribution. In order to effectively allocate resources, a virtual power management system with token ring communication is proposed.