A4 Conference proceedings

A Comparison of Small-Scale Gas Turbine Control Schemes


Publication Details
Authors: Jaatinen-Värri Ahti, Malkamäki Matti, Backman Jari, Honkatukia Juha
Publication year: 2017
Language: English
Related Journal or Series Information: ASME Turbo Expo
Title of parent publication: ASME Proceedings | Microturbines, Turbochargers and Small Turbomachines
Volume number: 8
ISBN: 978-0-7918-5095-4
JUFO-Level of this publication: 1
Open Access: Not an Open Access publication

Abstract

Throughout
the world there is pressure to increase distributed energy generation.
Driving factors include for example political and environmental concerns
in developed countries and reliability in places where centralized grid
does not either exist or is too unreliable. The energy generation based
on renewable fuels such as biogas is also usually decentralized. To
answer this demand, the number of small-scale gas turbine combined heat
and power (CHP) installations have increased. Due to its nature, the
required power output of distributed generation is highly variable. The
power output of decentralized power plant needs to follow the local
consumption power need and thus it needs to be efficiently controlled.
Therefore, the requirement for variable output necessitates that
small-scale gas turbines are often run at part-loads.

Previously,
most of the installed small-scale gas turbines have been single-spool
units with either fixed or variable speed shafts. Control schemes and
part-load performance are somewhat different for the two setups.
Recently, a two-spool gas turbine where the spools can be controlled
independently has been proposed as a feasible alternative. The
possibility to produce the desired power output with two spools, both
having their own generator, which can be controlled independently of
each other, offers significantly more possibilities for the control.
Therefore, it might also offer better part-load performance.

In
this paper, the control schemes of three different small-scale gas
turbines are compared. Especially, the part-load electrical efficiency
is studied. The studied gas turbines are: a single-spool fixed speed, a
single-spool variable speed driven, and a two-spool variable speed
driven gas turbine. The part-load performance of different machines is
studied and then compared against each other. Furthermore, some
estimations are given on how the part-load performance of each machine
fares against certain load profiles.


Last updated on 2019-29-03 at 08:48