Date of Graduation


Document Type


Degree Type



Statler College of Engineering and Mineral Resources


Lane Department of Computer Science and Electrical Engineering

Committee Chair

Ali Feliachi

Committee Co-Chair

Muhammad A. Choudhry

Committee Member

Muhammad A. Choudhry

Committee Member

Yaser P. Fallah

Committee Member

Vinod K. Kulathumani

Committee Member

Hong-Jian Lai


This dissertation develops and analyzes distributed controllers for power systems with renewable energy sources. A comprehensive state space modeling of voltage source inverters (VSIs) is developed specifically to address the secondary voltage control. This model can be used for simulation and control design. Unlike frequency, voltage is a local phenomenon, meaning that it cannot be controlled from a far distance. Therefore, a voltage zoning matrix that relates the sensitivity of the loads to the sources is proposed. The secondary voltage control is designed by applying the eigenvalue decomposition of the voltage zoning matrix to obtain the reference generators voltages. The developed algorithm in this study has been tested on multiple IEEE case studies, and the results show its effectiveness, yet it is a centralized control algorithm. To reduce the risk of a single point of failure in the centralized controllers, distributed secondary voltage controllers have been proposed in the recent literature. However, the communication messages are still exchanged among all controllers in the system. Therefore, a fully distributed algorithm is proposed in this dissertation study through the design of a communication layer by clustering the sources based on a developed sensitivity methodology. A modified IEEE 13 bus feeder with integrating renewable energy sources shows a significant improvement in time of convergence. A real communication protocol is then applied to the system to analyze the communication effect of packet loss and latency on the given distributed control system. Furthermore, to demonstrate the voltage control problem on the hardware-in-the-loop system, the detailed steps to implement the simulation model in the OPAL-RT real-time simulator (RTS) are discussed. The results of RTS coordinate with the software modeling outcomes.