Robust partial feedback linearizing excitation controller design for multimachine power systems

This paper presents a new robust nonlinear excitation
controller design for synchronous generators in multimachine power
systems to enhance the transient stability. The mismatches between
the original power system model and formulated mathematical model
are considered as uncertainties which are modeled through the
satisfaction of matching conditions. The exogenous noises appearing
from measurements are incorporated with the power system model
including the two-axis model of synchronous generators. The partial
feedback linearization technique is used to design the controller which
transforms the original nonlinear multimachine power system model
into several reduced-order linear and autonomous subsystems. The
desired control law is obtained for each subsystem and implemented in
a decentralized manner provided that the dynamics of the autonomous
subsystems have no effects on the overall stability of the system. The
analysis related to the dynamics of noisy autonomous subsystems is
also included and the proposed controller has the excellent capability
to decouple these noises. Finally, the performance of the proposed
control scheme is evaluated on an IEEE 39-bus benchmark power
system following different types of large disturbances. The performance
of the proposed controller is compared to that of a partial
feedback linearizing controller, which is designed without robustness
properties, to verify the effectiveness of the proposed control scheme.