Doctoral Dissertations


"This research proposes non-linear control architectures dedicated towards improving transient response, reliability and computational burden for grid connected inverters applicable for ac micro-grids. Also this work proposes an optimization procedure applied to a small microgrid to reduce the billing cost for power incorporating battery degradation mechanism.

Three works are discussed in this research that discusses methodologies to improve the operation of a three phase grid connected inverters. The first work discusses a globally stable estimation architecture for estimating the plant parameters for a grid connected inverter during its operation. Then a Lyapunov based control architecture is utilized and online parameter update scheme is used to optimize the controller performance. The second work discusses a Lyapunov based control architecture during a contingency that the grid voltage sensor fails. In this work an internal model based grid voltage estimation architecture has been proposed which successfully estimates the grid voltage and controls the grid current. The last work shows a methodology to optimally utilize a battery in a microgrid based on Markov Decision Process. Dynamic algorithm is used to solve the problem so that the cost is minimized at the end of the day.

Furthermore, in this research detailed stability analysis of the first two works along with the controller design has been presented. Also in this work, battery degradation is modelled empirically and the overall cost function is obtained for the optimization of billing cost for a small microgrid.

Detailed plant modeling, controller design, simulation and experimental results are presented for all of the proposed schemes"--Abstract, page iv.


Kimball, Jonathan W.

Committee Member(s)

Sarangapani, Jagannathan, 1965-
Crow, Mariesa
Bo, Rui
Park, Jonghyun


Electrical and Computer Engineering

Degree Name

Ph. D. in Electrical Engineering


Missouri University of Science and Technology

Publication Date

Fall 2019

Journal article titles appearing in thesis/dissertation

  • Control of a three phase grid connected inverter under non-ideal grid conditions with online parameter update
  • Grid voltage sensorless synchronization of a three-phase grid connected inverter under unbalanced grid voltage condition
  • Optimal battery scheduling in a microgrid based on Markov decision process for cost minimization


xii, 82 pages

Note about bibliography

Includes bibliographic references.


© 2019 Vikram Roy Chowdhury, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 11645

Electronic OCLC #