Application of new POSICAST control method to synchronous generator excitation system

Hamidreza Ghorbani, Mehdi Monadi, Amir Ghorbani, Jose Ignacio Candela


In this paper, modeling, analysis, design and simulation of a POSICAST controller are presented for application in a generator’s
excitation system. Simple structure is the most important characteristic of this controller. The controller is a feedforward
compensator; it eliminates intensive over/undershoots in system dynamic response. Since changing the reference signal in
the excitation system of the synchronous generator causes oscillations in the terminal voltage, the POSICAST controller (PC)
is applied at the outset of the excitation system to mitigate these oscillations. The impact of the proposed controller on the
stability of the studied power system is evaluated by both eigenvalues analysis and experimental results. In order to validate
the theory, the performance of the designed controller is verified in OPAL-RT by experimental approach.


POSICAST controller; generator excitation system; automatic voltage regulator (AVR); real time simulation; eigenvalues analysis.

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