Re: [microhydro] Re: correcting power factor
- With regard to all the problems being talked about in relation to difficult
power factor regulation, doesn't anyone agree with me that a standard robust
brushless alternator is easier and cheaper than having all these capacitor
banks and unknown line characteristics and hence very unpredictable voltages ?
- Rupert -
Yes - I agree - induction machines are w/out brushes and can
often more readily handle runnaway speed - these are the only two
aspects of induction generators in my opinion.
A proper sync. generator gives far better eff and positive control
of power facter. Especially in the case example that started this
discussion - moderate capacity site at the end of a weak grid
extension - Power factor control is essential to reduce var usage -
even contribute vars to a weak system is a real benefit.
Even in the small system running mostly transformers for
flouresent lamps - adjustable ( with excitation control) PF would
greatly simplify the problem.
--- In email@example.com, evansengineering@c... wrote:
> With regard to all the problems being talked about in relation to
> power factor regulation, doesn't anyone agree with me that a
> brushless alternator is easier and cheaper than having all these
> banks and unknown line characteristics and hence very unpredictable
- Thanks to all for the advice so far. I believe the peltric sets here are all
induction generators, and I think they're brushless, but maybe Ghanashyam
can correct me on this one. Each house will probably have their own switch,
so there could be quite a variation in load. I'm pretty sure all the PFs
were lagging, but I'll have to confirm that. The voltage will be about 220
and a maximum of 2A generated (around 4 - 4.5 kW).
From: ellwood@... [mailto:ellwood@...]
Sent: Sunday, October 01, 2000 8:07 AM
Subject: [microhydro] Re: correcting power factor
>150 households to power about400 lamps.Does each house hold have there own switch for the lights or are they
controlled by several master switches? If controlled by several
master switches it would be easier to control pf of each bank of
> have shown that locally available 7W-15W CFLs with integratedballasts have
> power factors of 0.5-0.6, while the non-integrated CFLs withmagnetic
> ballasts have PFs of 0.3-0.4.As Hugh suggests if some have a leading power factor maybe a
combination of both leading and lagging may work.
Are you using an induction generator? If so the excitation
capacitance will be used in trying to pf correct the laod and
generation will be lost.
To work out the pf of the load I would probably need to know the
voltage / current and the percentage of how many lamps are expected
be on at a time. With that information it shouldn't be to hard to do
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