Conference Paper

A Genetic Algorithm Solution to the Governor-Turbine Dynamic Model Identification in Multi-Machine Power Systems

Student Member, IEEE, School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332 USA (e-mail: )
DOI: 10.1109/CDC.2005.1582336 Conference: Decision and Control, 2005 and 2005 European Control Conference. CDC-ECC '05. 44th IEEE Conference on
Source: IEEE Xplore


Speed governors are key elements in the dynamic performance of electric power systems. Therefore, accurate governor models are of great importance in simulating and investigating the power system transient phenomena. Model parameters of such devices are, however, usually unavailable or inaccurate, especially when old generators are involved. Most methods for speed governor parameter estimation are based on measurements of frequency and active power variations during transient operation. This paper proposes a genetic algorithm based optimization technique for parameter estimation, which makes use of such measurements. The proposed methodology uses a real-coded genetic algorithm. The paper estimates the parameters of all system generators simultaneously, instead of every machine independently, which is fully in line with the interest to treat the electric power system as a whole and study its comprehensive behaviour. Moreover, the methodology is not model-dependent and, therefore, it is readily applicable to a variety of model types and for many different test procedures. The proposed methodology is applied to the electric power system of Crete and the results demonstrate the feasibility and practicality of this approach.

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Available from: Nikos D. Hatziargyriou
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    • "Studies on parameter identification methods of steam turbine governor for different simulation cycles can be found in [6] [7] [8] [9] [10] [11]. The fixed oil motive opening and closing time constants are adopted in the existing literatures and power system simulation software settings [9] [10] [11] [12], but they are difficult to be applied to the nonlinear characteristics of some thermal power plant actuator valve's fully open or close test. As for the nonlinear valve of hydroturbine, certain existing literature uses several sets of proportional integral derivative (PID) parameters to meet the different operating conditions [13]. "
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