Project Title:

A Variable-Speed, Constant-Frequency, Integral, Induction Starter-Generator

92-1-01.02-0540A                                                  NAS03-26723
A Variable-Speed, Constant-Frequency, Integral,
     Induction Starter-Generator
Satcon Technology Corporation
12 Emily Street
Cambridge, MA  02139-4507
James R. Downer                                      (617-661-0540)

Abstract:

     Turbine engines are started via an electric starter driven by
a start cart. The starter spins the gas generator to the minimum
speed for igniting the combustor, then accelerates the engine to
idle. In flight, electric power is provided by a separate
generator. This project will develop a preliminary design of an
integral starter-generator (IIS-G) based on an induction machine.
The IIS-G will reside within a turbine engine and replace the
existing starter and integral drive generator. An IIS-G will
benefit overall engine design weight and performance, and will
either allow for the redesign or elimination of the auxiliary
gearbox. This system will also allow the bypass air ducting to be
redesigned for optimum thrust. The IIS-G will be compatible with
aircraft electric power distribution systems employing pulse-
density modulation, which have been developed at the NASA Lewis
Research Center.

Potential Commercial Application:

Potential Commercial Applications:  The integral induction
starter-generator will be immediately marketable to aircraft
engine manufacturers for use in advance system developments for
the integrated high-performance turbine engine technology
initiative. Major manufacturers are interested in this technology
because eliminating the auxiliary gearbox will reduce weight.

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