Journal of Power and Energy Engineering, 2014, 2, 312-333
Published Online April 2014 in SciRes. http://www.scirp.org/journal/jpee
http://dx.doi.org/10.4236/jpee.2014.24043
How to cite this paper: Aziz, A., Mto, A. and Stojsevski, A. (2014) Automatic Generation Control of Multigeneration Power
System. Journal of Power and Energy Engineering, 2, 312-333. http://dx.d oi.org/10.4236/j pe e. 2014.24043
Automatic Generation Control of
Multigeneration Power System
Asma Aziz, Amanullah Mto, Alex Stojsevski
Faculty of Science, Engineering and Built Environment Deakin University Geelong, Geelong, Australia
Email: aazi@deakin.edu.au
Received February 2014
Abstract
Load frequency Control (LFC) is used for many years as part of Automatic Generation Control (AGC)
in power system around the world. In a mixed power system, it is usual to find an area regulated
by hydro generation interconnected to another area regulated by thermal generation or in com-
bination of both. In the following study, performance of AGC for Thermal, Hydro and Thermal tur-
bine based power system is examined, including how frequency bias setting influences AGC re-
sponse and inadvertent interchange. Control performance analysis of three area interconnected
systems is simulated and studied through Matlab Simulink software. Integral square error and
Integral time absolute error has been used as performance criterion. It is shown that integral time
absolute error (ITAE) as performance index leads to faster optimization of controller gain.
Keywords
Automatic Generation Control; Performance Index; ISE; ITA E; Discrete Controller
1. Introduction
Today’s power system consists of control areas with many generating units with outputs that must be set ac-
cording to economics. The analysis and design of Automatic Generation Control (AGC) system of individual
generator eventually controlling large interconnections between different control areas play a vital role in auto-
mation of power system. The purposes of AGC are to maintain system frequency very close to a specified no-
minal value, to maintain generation of individual units’ at the most economic value, to keep the correct value of
tie-line power between different control areas. Automatic Generation Control (AGC) is defined by IEEE [1] as
the regulation of the power output of electric generators within a prescribed area in response to changes in sys-
tem frequency, tie-line loading, or the regulation of these to each other, so as to maintain the scheduled system
frequency and/or the established interchange with other areas within predetermined limits. AGC has evolved ra-
pidly from tie the time when the function was performed manually, through the days of analog systems to the
present application of sophisticated direct digital control systems. The AGC problem has been extensively stu-
died during the last four decades. Most of the work concentrates on the net interchange tie-line bias control
strategy making use of the area control error (ACE). The existence of ACE means that there is excess or defi-
cient of spinning stored energy in an area and a correction to stored energy is required to restore the system fre-
quency to scheduled value. The early work on AGC has been reported by many authors. Cohn [2,3] has exten-