A Cars forum. AutoBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AutoBanter forum » Auto newsgroups » Technology
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Genset voltage reg: capacitor vs. AVR



 
 
Thread Tools Display Modes
  #71  
Old February 21st 13, 05:57 PM posted to rec.crafts.metalworking,alt.home.repair,rec.autos.tech
Transition Zone
external usenet poster
 
Posts: 8
Default Genset voltage reg: capacitor vs. AVR

On Feb 21, 11:50*am, " >
wrote:
> On Feb 21, 11:35*am, Transition Zone > wrote:
>
>
>
>
>
>
>
>
>
> > On Feb 20, 7:58*am, " >
> > wrote:

>
> > > On Feb 19, 4:56*pm, Transition Zone > wrote:

>
> > > > On Feb 19, 1:54*pm, (Scott Dorsey) wrote:

>
> > > > > > wrote:
> > > > > >On Feb 18, 11:12=A0am, (Scott Dorsey) wrote:
> > > > > >> > wrote:
> > > > > >> With a conventional AC generator, the speed of the engine governs the
> > > > > >> output frequency. =A0The generator HAS to run at constant speed, usually
> > > > > >> 1800 rpm, in order to get 60 Hz out of the generator. =A0Change the engin=
> > > > > >e
> > > > > >> speed, you change the line frequency.

>
> > > > > >No **** sherlock and you also change the voltage.

>
> > > > > Possibly for one fraction of a cycle, but as soon as there is any change, the
> > > > > field coil voltage will be increased to compensate for it. *The mechanical
> > > > > feedback loop that controls the engine speed is very very slow, because it
> > > > > is limited by the inertia of the engine an the rotor. *The electrical feedback
> > > > > loop that controls the field coil voltage is pretty fast; it is limited
> > > > > mostly by the inductance of the field coil.

>
> > > > > >> This is why conventional AC generators ALL have a device to regulate the
> > > > > >> field coil voltage in order to get constant output voltage. =A0Some of th=
> > > > > >ese
> > > > > >> devices are better than others.

>
> > > > > >That's true and why EA is asking about a cap versus
> > > > > >a ture electronic voltage regulator.

>
> > > > > And what does he mean by "a cap?" *As I said earlier, you have two choices
> > > > > for voltage regulation: a feedback loop controlled by a mechanical buzzer, or

>
> > > > *>a feedback loop controlled by a solid state device. * What is this
> > > > mysterious

>
> > > > > *"capacitor regulation" that he has come up with?

>
> > > > A cap is a given as a capacitor. You regulate voltage, raising it
> > > > means you lower its current. Increasing the current means you can run
> > > > something faster, like a fan, but you lower the voltage, so you are
> > > > regulating it in that sense. *But the power is what always remains the
> > > > same (assuming reaction in the circuit isn't a factor).- Hide quoted text -

>
> > > Sigh.....

>
> > Oh, and with a split-phased capacitor, part of one phase can be used
> > to help start a motor before its brought back to normal running the
> > motor.- Hide quoted text -

>
> > - Show quoted text -

>
> Sigh... None of which has any relevance to how a cap is used
> to regulate voltage in a cheap generator.


Why expect to regulate voltage if its that cheap?
Ads
  #72  
Old February 21st 13, 06:16 PM posted to rec.crafts.metalworking,alt.home.repair,rec.autos.tech
[email protected][_2_]
external usenet poster
 
Posts: 65
Default Genset voltage reg: capacitor vs. AVR

On Feb 21, 11:57*am, Transition Zone > wrote:
> On Feb 21, 11:50*am, " >
> wrote:
>
>
>
> > On Feb 21, 11:35*am, Transition Zone > wrote:

>
> > > On Feb 20, 7:58*am, " >
> > > wrote:

>
> > > > On Feb 19, 4:56*pm, Transition Zone > wrote:

>
> > > > > On Feb 19, 1:54*pm, (Scott Dorsey) wrote:

>
> > > > > > > wrote:
> > > > > > >On Feb 18, 11:12=A0am, (Scott Dorsey) wrote:
> > > > > > >> > wrote:
> > > > > > >> With a conventional AC generator, the speed of the engine governs the
> > > > > > >> output frequency. =A0The generator HAS to run at constant speed, usually
> > > > > > >> 1800 rpm, in order to get 60 Hz out of the generator. =A0Change the engin=
> > > > > > >e
> > > > > > >> speed, you change the line frequency.

>
> > > > > > >No **** sherlock and you also change the voltage.

>
> > > > > > Possibly for one fraction of a cycle, but as soon as there is any change, the
> > > > > > field coil voltage will be increased to compensate for it. *The mechanical
> > > > > > feedback loop that controls the engine speed is very very slow, because it
> > > > > > is limited by the inertia of the engine an the rotor. *The electrical feedback
> > > > > > loop that controls the field coil voltage is pretty fast; it is limited
> > > > > > mostly by the inductance of the field coil.

>
> > > > > > >> This is why conventional AC generators ALL have a device to regulate the
> > > > > > >> field coil voltage in order to get constant output voltage. =A0Some of th=
> > > > > > >ese
> > > > > > >> devices are better than others.

>
> > > > > > >That's true and why EA is asking about a cap versus
> > > > > > >a ture electronic voltage regulator.

>
> > > > > > And what does he mean by "a cap?" *As I said earlier, you have two choices
> > > > > > for voltage regulation: a feedback loop controlled by a mechanical buzzer, or

>
> > > > > *>a feedback loop controlled by a solid state device. * What is this
> > > > > mysterious

>
> > > > > > *"capacitor regulation" that he has come up with?

>
> > > > > A cap is a given as a capacitor. You regulate voltage, raising it
> > > > > means you lower its current. Increasing the current means you can run
> > > > > something faster, like a fan, but you lower the voltage, so you are
> > > > > regulating it in that sense. *But the power is what always remains the
> > > > > same (assuming reaction in the circuit isn't a factor).- Hide quoted text -

>
> > > > Sigh.....

>
> > > Oh, and with a split-phased capacitor, part of one phase can be used
> > > to help start a motor before its brought back to normal running the
> > > motor.- Hide quoted text -

>
> > > - Show quoted text -

>
> * > *Sigh... None of which has any relevance to how a cap is used
>
> > *to regulate voltage in a cheap generator.

>
> Why expect to regulate voltage if its that cheap?- Hide quoted text -
>
> - Show quoted text -


Another diversion into lala land. They apparently do it
because:


A - If you're not going to use an electonic voltage regulator which
costs a bit more, then having SOME voltage regulation on a generator
is better than none.

B - Customers want and expect some kind of voltage regulation
and the generator would probably be useless for most applications
without it.

C - A cap is cheap
  #73  
Old February 21st 13, 06:33 PM posted to rec.crafts.metalworking,alt.home.repair,rec.autos.tech
Tim Wescott[_2_]
external usenet poster
 
Posts: 9
Default Genset voltage reg: capacitor vs. AVR

On Mon, 18 Feb 2013 11:18:45 -0500, Scott Dorsey wrote:

> Tim Wescott > wrote:
>>
>>Do you have a link to a site that sells the AVR ditty? If it's
>>regulating the field current of the generator in response to the
>>generator voltage, and if all the genset does is rely on the motor's
>>governor for speed regulation, then it should give better regulation.

>
> As far as I know, every non-inverter generator works this way. How else
> would you get a stable output voltage with varying loads? It's not like
> field coil regulation is terribly expensive; it's not a whole lot of
> current in there.


With field coil regulation you should be able to keep the genset voltage
dead nuts on target, with deviations only when the load changes suddenly.

One wonders in what decade the technology stalled if they're allowing the
crappy regulation that EA quotes.

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com
  #74  
Old February 21st 13, 07:49 PM posted to rec.crafts.metalworking,alt.home.repair,rec.autos.tech
[email protected][_2_]
external usenet poster
 
Posts: 65
Default Genset voltage reg: capacitor vs. AVR

On Feb 21, 12:33*pm, Tim Wescott > wrote:
> On Mon, 18 Feb 2013 11:18:45 -0500, Scott Dorsey wrote:
> > Tim Wescott > wrote:

>
> >>Do you have a link to a site that sells the AVR ditty? *If it's
> >>regulating the field current of the generator in response to the
> >>generator voltage, and if all the genset does is rely on the motor's
> >>governor for speed regulation, then it should give better regulation.

>
> > As far as I know, every non-inverter generator works this way. *How else
> > would you get a stable output voltage with varying loads? *It's not like
> > field coil regulation is terribly expensive; it's not a whole lot of
> > current in there.

>
> With field coil regulation you should be able to keep the genset voltage
> dead nuts on target, with deviations only when the load changes suddenly.
>
> One wonders in what decade the technology stalled if they're allowing the
> crappy regulation that EA quotes.
>
> --
> Tim Wescott
> Control system and signal processing consultingwww.wescottdesign.com


I don't know, but the generator head is made by Meccalte,
an Italian manufacturer of real electric gear. You would think
on a generator that costs $2800 you'd get electronic voltage
regulation. But they apparently use a cap.
  #75  
Old February 21st 13, 08:17 PM posted to rec.crafts.metalworking,alt.home.repair,rec.autos.tech
Scott Dorsey
external usenet poster
 
Posts: 3,914
Default Genset voltage reg: capacitor vs. AVR

Jim Wilkins > wrote:
>"Scott Dorsey" > wrote in message
>> > wrote:
>>
>> Looking at how this works, it's not a conventional brush-type
>> alternator at
>> all, but an induction device almost like an induction motor in
>> reverse. The
>> patent shows a single pole rotor with a diode across the winding, so
>> the
>> rotor acts as a magnetic short in one direction and a magnetic open
>> in the
>> other. This diode is really the key to the trick.
>>

>
>
http://en.wikipedia.org/wiki/Magnetic_amplifier
>"A relatively small DC current on the control winding is able to
>control or switch large AC currents on the AC windings. This results
>in current amplification."


No, read the patent! It's not related to magnetic amplifiers at all;
nothing is operating in saturation. It is a very cool trick!
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
  #76  
Old October 23rd 17, 05:44 PM posted to rec.crafts.metalworking,alt.home.repair,rec.autos.tech
anonymous
external usenet poster
 
Posts: 1
Default Genset voltage reg: capacitor vs. AVR

replying to Pete S, anonymous wrote:
sumec fireman....the smallest


--
for full context, visit https://www.homeownershub.com/mainte...vr-736855-.htm


 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Radio interference capacitor - 2001 Explorer George Csahanin Ford Explorer 3 August 28th 09 12:15 AM
Testing an alternator: Using a stiffening capacitor [email protected] Technology 10 June 2nd 06 02:18 PM
AWA [OFFER] 40KW Genset new [email protected] General 0 April 5th 06 11:51 PM
ignition condenser [= radio noise capacitor] - revisited Elle Honda 13 November 7th 05 06:36 PM
Turbo Parallel Hybrid, Li-ion Capacitor [email protected] Technology 2 September 23rd 05 10:55 AM


All times are GMT +1. The time now is 02:32 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AutoBanter.
The comments are property of their posters.