Doctoral Dissertations

Keywords and Phrases

Unified Power Flow Controller (UPFC)


"Power system oscillations occur in power networks as a result of contingencies such as faults or sudden changes in load or generation. They are detrimental to the operation of the system since they affect system stability and the optimal power flow through it. These oscillations do not usually damp out in tie-lines unless certain controls are applied to the system. Local and inter-area oscillations have traditionally been controlled by Power System Stabilizers (PSS). However, Flexible Alternating Current Transmission Controllers (FACTS) have significant potential as alternatives to PSS. The main goal of this research is to damp inter-area oscillations by Unified Power Flow Controllers (UPFC). UPFC is a series-shunt FACTS device which is used for purposes such as the control of active and reactive power flow through the corridors of the system. However, using supplementary controls and proper coordination of UPFCs, they can be used for fast damping of inter-area oscillations in multi-area power systems"--Abstract, page iv.


Crow, Mariesa

Committee Member(s)

Chowdhury, Badrul H.
McMillin, Bruce M.
Ferdowsi, Mehdi
Sarangapani, Jagannathan, 1965-


Electrical and Computer Engineering

Degree Name

Ph. D. in Electrical Engineering


Missouri University of Science and Technology

Publication Date

Fall 2008

Journal article titles appearing in thesis/dissertation

  • Effect of various UPFC operating points on transient stability
  • Existence of multiple equilibria in the UPFC power injection model
  • Discussion on effective control of inter-area oscillations by UPFCs
  • Novel approach to inter-area oscillation damping by UPFC voltage control
  • Decentralized control and placement of multiple UPFCs for damping interarea oscillations: an LMI approach
  • Damping inter-area oscillations by UPFCs based on selected global measurements
  • Damping inter-area oscillations in power systems by STATCOMs
  • Nonlinear control of FACTS devices for damping inter-area oscillations in wide-area power systems
  • Optimal placement and signal selection for wide-area controlled UPFCs for damping power system oscillations
  • Dynamic placement and signal selection for UPFCs in wide-area controlled power systems


xv, 165 pages

Note about bibliography

Includes bibliographical references.


© 2008 Mahyar Zarghami, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Subject Headings

Electric power systems
Flexible AC transmission systems

Thesis Number

T 9467

Print OCLC #


Electronic OCLC #