Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!rutgers!ames!oliveb!sun!cmcmanis
From: cmcmanis@sun.uucp (Chuck McManis)
Newsgroups: sci.electronics
Subject: Re: Syncronizing Generators
Message-ID: <17838@sun.uucp>
Date: Fri, 1-May-87 16:47:04 EDT
Article-I.D.: sun.17838
Posted: Fri May  1 16:47:04 1987
Date-Received: Sun, 3-May-87 02:33:36 EDT
References: <923@mhuxh.UUCP> <1715@kitty.UUCP> <243@omssw1.UUCP> <2642@phri.UUCP> <561@neoucom.UUCP>
Organization: Sun Microsystems, Inc. - Mtn View, CA
Lines: 32
Summary: Motors spin those puppies.

In article <561@neoucom.UUCP>, wtm@neoucom.UUCP (Bill Mayhew) writes:
> Roy's article got me wondering what your friendly local power
> company does when they want to put an additional alternator on
> line.  It must be pretty tricky to match the rpm, and then the
> phase angle of the output waveform too.

> I've had a mental image of the operators getting the rotation of
> the machine matched up as close as possible and then taking cover
> as the machine lurches into phase with the rest of the power grid.

> It seems like the multipole generators used in hydroelectric plants
> would be especially tricky since they spin at relatively low rpm.
> I suppose that in a hydroelectric plant, you could start out by
> motoring the alternator and then letting the water add useful power
> when the machine was up to speed.
>   --Bill

When I went on a tour of one of PG&E's facilities for a class in 
Electromechanics we noticed a row of big diesal(sp) engines. When 
asked if they were backups for the steam turbines the answer was
"No, they are for cold starting the plant. When bringing a new 
generator on line power from the grid is allowed to spin it up to 
speed using it as a motor. As it gets closer to the speed and 
phase of the power line it is stabilized. Then the steam vents 
are opened and it switches over from using power to producing 
power at the same phase as the voltage that started it." 

-- 
--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
These views are my own and no one elses. They could be yours too, just
call MrgCop() and then ReThinkDisplay()!