Investigation into the impact of Powerformer design on power system operational security

Aumuller, Craig Anthony. (2003). Investigation into the impact of Powerformer design on power system operational security PhD Thesis, School of Information Technology and Electrical Engineering, The University of Queensland.

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
THE16901.pdf Full text application/pdf 18.56MB 6
Author Aumuller, Craig Anthony.
Thesis Title Investigation into the impact of Powerformer design on power system operational security
School, Centre or Institute School of Information Technology and Electrical Engineering
Institution The University of Queensland
Publication date 2003
Thesis type PhD Thesis
Supervisor Dr Tapan Saha
Mr Peter Wright
Total pages 200
Collection year 2003
Language eng
Subjects L
290901 Electrical Engineering
660301 Electricity transmission
Formatted abstract
In February 1998 a new and unique form of power generator, the Powerformer TM , was introduced into the marketplace. The Powerformer can be operated at transmission system level voltage without the need for a step up transformer and consequently has unique system support capabilities. The aim of the research work, presented in this thesis, was to investigate the unique aspects of the Powerformer from a power system perspective, in order to facilitate optimal power system operation and security.

The main focus of the research undertaken by the author of this thesis was to investigate the impact of Powerformer on the relative voltage stability of a power system. The driving force behind the author's desire to look at the impact of the Powerformer on power system voltage stability and security was the realisation that voltage stability issues are becoming increasingly important. The focus for today's modem power transmission systems is undergoing a radical shift from a purely publicly provided service to a financially driven commodity. This ultimately means that power systems are increasingly under pressure to be utilised to their fullest capacity without the need to install new, expensive and sometimes socially unpopular system equipment and facilities. The problem with this situation is that a system's stability can be affected greatly by loading conditions. When a system is heavily loaded the voltage stability limit, rather than the transient angle stability limit constrains its operation. It is for this reason that voltage stability concerns in particular are increasingly being discussed in the literature and becoming an issue for power system operators.

A number of different static and dynamic system analysis techniques have been reviewed and compared in this thesis, with the results of these comparisons presented and discussed in this thesis. Amongst the methods discussed in this thesis, methods for use in voltage stability analysis and assessment have been proposed and presented by the author of this thesis. The most suitable techniques are being utilised to determine how the Powerformer can aid in safe system operation under a number of different system contingencies in a number of different test systems, including the 600+ bus Queensland Transmission System. Particular emphasis has been placed in this research on long-term system dynamics.

Two major aspects of the Powerformer that differ it from conventional are the lack of a step up transformer and the ability of the Powerformer stator to be overloaded for longer periods than conventional power generators. The lack of a step up transformer means that power that would normally be lost can be supplied to the system and that the high voltage bus, normally on the opposite side of the step up transformer, is directly controlled. The overload capability of the Powerformer means that it can supply reactive power support to the power system for a longer period than a conventional generator.

Investigations undertaken into the Powerformer have shown it to have a potentially beneficial ability to allow greater system loading capability and therefore system security margins and a potentially beneficial impact on the time to voltage collapse following a system contingency.
Keyword Power resources

Document type: Thesis
Collection: UQ Theses (RHD) - UQ staff and students only
Citation counts: Google Scholar Search Google Scholar
Created: Fri, 24 Aug 2007, 18:10:39 EST