Development of Early Warning Methods for Electric Power Systems

 

PhD project 

by Hjörtur Jóhannsson

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Presentation

Date & Time:    Tuesday, 14 June 2011, at 13:00

Location:          DTU, Building 101A, Meeting Centre S9

Examiners:       Adjunct Professor Prabha S. Kundur
                            Kundur Power Systems Solutions Inc., Canada

                       Professor Göran Andersson
                            Power Systems Group, ETH Zürich, Switzerland

                       Professor Erik Bruun
                            DTU Electrical Engineering, Denmark

Chairman:        Professor Morten Lind
                            DTU Electrical Engineering, Denmark

A copy of the PhD thesis is available for reading at the department 14 days before the defence. 

Period
April 2007 to August 2011

Supervisors
Principal supervisor: Associate Professor Arne Hejde Nielsen
     CET, DTU Electrical Engineering
Co-supervisor: Professor Jacob Østergaard
     CET, DTU Electrical Engineering

Description

Background
In a traditional power system, the electricity is produced in relatively few but large central power plants and the electrical transmission system has been build up with a focus on the transmission of the power from these plants toward some nodes in the system, wherefrom the power is distributed to the consumers.

In a power system where a significant part of the power is produced by means of renewable energy sources, the power production becomes more decentralized where the production units are relatively small and spread over large area in the power system.
In power systems where the amount of renewable power production has significantly been increased, the existing transmission system is not always designed to cope with the new transmission requirements. In many cases, it would be desirable to strengthen existing transmission system. Due to an increasing political and public resistance against further expansion of the high voltage transmission grid, future expansions could possible be limited.

Another possible solution could be an operation of the existing transmission system closer to the stability limits for the system which requires a trustworthy online monitoring of these limits.

The formation of the power system towards increasing utilization of renewable energy sources combined with generally more stressed transmission system necessitates a research within the field of on-line assessment of power system stability.

 
The main subject of the project
The overall purpose of the project is to develop methods that can provide, in real-time, an early warning for an emerging stability problem. The 2003

blackout in E-Denmark and S-Sweden is a case scenario for motivation of the work. For achieving this overall objective, several goals are defined that

together contribute to an early warning method:

  • Express system stability boundaries in variables that can easily be obtained from wide-area PMU-observations.
  • Derive methods for stability assessment, which are capable of detecting when stability boundaries are crossed and quantify the margin from a given operating point to its critical boundary.
  • Visualize the observed system conditions such that the distance of an operating point to its stability boundary is represented, which thereby provides a mean of visual identification of critical elements.
  • Develop algorithms that enable real-time usage of the developed assessment method.

Receive grant from Mogens Balslev Foundation 2009

Further information
• ORBIT database

July 2011 hj
 

https://www.cee.elektro.dtu.dk/research/phd-projects/completed-phd-projects/06-10/hj
13 DECEMBER 2024