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Department of electric
power engineering
2014 - 2018
Design of Variable
Speed Generators
for Hydropower
Applications
Supervisor:
Arne Nysveen
Co-supervisor:
Robert Nilssen
Erlend L. Engevik
Background
The power system is experiencing an increasing
share of electric power production that comes
from intermittent power sources like wind and
solar. Increased pressure is put on controllable
power sources like hydropower to deal with
fluctuations in the output of electric power
production.
Generators used in hydropower plants today are
not designedandoptimized for frequent changes
in active power production. The main purpose of
this work is to develop optimum synchronous
generator designs where the speed of rotation
and electrical frequency is allowed to vary within
given intervals.
Results indicates that the highest efficiency
is achieved at low nominal frequencies, while
generator weight is reduced substantially at
higher nominal frequencies. Cost optimization
where both losses and use of materials are
taken into account indicates that a nominal
frequency around 50 Hz will achieve the
lowest total cost. There are also cost benefits
associated with increasing the maximum values
of the synchronous reactance, but this does also
cause several possible design issues that will
have to be resolved.
PHD THESIS