  Salient pole synchronous generators as the main component of an electricity
generation station should be carefully maintained and their operation has to be
monitored such that any damage on them is avoided. Otherwise, the generating
station might experience frequent shut downs which results in electricity
generation interruptions and high costs associated with repairing and
compensation of lack of energy. In this sense, many protective schemes focusing
on a variety of synchronous generator faults have already been proposed and are
still modified and developed to further enhance the quality of protection. In
this thesis, synchronous generator stator windings to ground fault is studied
as one of the most common and crucial faults in these machines. Numerous
methods of stator winding to ground fault protection schemes are also reported
in the literature. Third harmonic differential voltage and sub-harmonic schemes
are studied in this research. A novel adaptive scheme for both methods is
modelled and implemented in a comprehensive lab scale set-up where a real
generation unit is scaled down including all different components and
apparatus. The simulation model is also established based on simultaneous
finite element analysis (FEA) and coupled magnetic circuit to assist with
system configuration design and parameter selections. The adaptive scheme is
proved to be capable of detecting stator windings to ground faults based on
actual experimental data. Finally, the proposed adaptive scheme is compared
against other available non-adaptive protection schemes currently used in
industrial relays. Several important performance evaluation criteria in
protection schemes such as sensitivity and security of operation referred to as
reliability are considered. It is shown that the adaptive scheme offers higher
reliability than other schemes which emphasizes its credibility and
applicability.
