Abstract:
Current trends indicate that modern power
systems are continuously working under stressed conditions.
Power demand is rising constantly while several generators
are connected to work synchronously to meet the demand.
Occasionally, faults within a system occur, which induce
electromechanical oscillations of the electrical generators.
These oscillations, also called power swings, must be
effectively damped to maintain the system stability.
Additionally, due to these faults, bus voltages are reduced.
The high reactive power demand by the induction motor
load during fault condition due to reduced bus voltages causes
the generator to behave like a voltage source behind the
synchronous reactance and its terminal voltage reduces
leading to the possibility of a voltage collapse scenario. For
reliability of these systems, and in an attempt to reduce system
oscillations, Power System Stabilizers (PSS) have used to add
damping by controlling the excitation system. Studies have
shown that a well-tuned PSS using a Fuzzy Logic Controller
can effectively improve power system dynamic stability.
This paper investigates the impact of the FLPSS in
maintaining voltage stability. A large induction motor is
introduced as a load in a multi machine system, and the impact
of the FLPSS are investigated by introducing a temporary
three phase fault. For comparison the FLPSS is compared to
other PSS found in literature. Results indicate that the FLPSS
may lead the generator to lose its capability to maintain
constant voltage and hence lead to the st
