Transmission expansion planning (TEP) is a rather complicated process which requires extensive studies to determine when, where and how many transmission facilities are needed. A well planned power system will not only enhance the system reliability, but also tend to contribute positively to the overall system operating efficiency. Starting with two mixed-integer nonlinear programming (MINLP) models, this paper explores the possibility of applying AC-based models to the TEP problem. Two nonlinear programming (NLP) relaxation models are then proposed by relaxing the binary decision variables. A reformulation- linearization-technique (RLT) based relaxation model in which all the constraints are linearized is also presented and discussed in the paper. Garvers's 6-bus test system and the IEEE 24-bus system are used to test the performance of the proposed models and related solvers. A validation process guarantees that the resultant TEP plan is strictly AC feasible. The simulation results show that by using proper reformulations or relaxations, it is possible to apply the AC models to TEP problems and obtain a good solution.

Original languageEnglish (US)
Title of host publication2012 IEEE Power and Energy Society General Meeting, PES 2012
StatePublished - Dec 11 2012
Event2012 IEEE Power and Energy Society General Meeting, PES 2012 - San Diego, CA, United States
Duration: Jul 22 2012Jul 26 2012

Publication series

NameIEEE Power and Energy Society General Meeting
ISSN (Print)1944-9925
ISSN (Electronic)1944-9933


Other2012 IEEE Power and Energy Society General Meeting, PES 2012
Country/TerritoryUnited States
CitySan Diego, CA


  • Transmission expansion planning
  • mathematical programming
  • reformulation
  • relaxation

ASJC Scopus subject areas

  • Energy Engineering and Power Technology
  • Nuclear Energy and Engineering
  • Renewable Energy, Sustainability and the Environment
  • Electrical and Electronic Engineering


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