This paper presents the comparison and performance
evaluation of synchronous machine excitation models. The two
models, DC1A and AC4A, are among the IEEE standardized model
structures for representing the wide variety of synchronous machine
excitation systems. The performance evaluation of these models is
done using SIMULINK simulation software. The simulation results
obtained using transient analysis show that the DC1A excitation
system is more reliable and stable than AC4A excitation system.
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