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A More Efficient Bridge Rectifier?

P

PovTruffe

Jan 1, 1970
0
Joerg said:
Be glad you don't live in some parts of Europe where they give solar panel owners huges sums per kWh. Guess who ends
up paying that hidden tax?

In France at least it is not hidden. The added cost of the solar / wind energy
appears separately on the electricity bill.
 
H

Hammy

Jan 1, 1970
0
In France at least it is not hidden. The added cost of the solar / wind energy
appears separately on the electricity bill.
The thing that kills me is that solar and wind aren't really
environmentally friendly! The amount of land required to generate even
modest amounts of energy is vast. The land has to be cleared roads
have to be built, equipment run in and out.

Nobody really knows what effect the large magnet field that those huge
wind turbines generate have on wildlife and people. The other thing is
it's unreliable.

The only reason it's gaining popularity is because governments are
handing out lucrative contracts and incentives to 21'st century snake
oil salesman to appease a bunch of uninformed people. Tell me what you
want to hear and pay me enough and I'll tell you.

The most environmentally friendly method is nuclear. It's also the
most reliable and generates the most output for its footprint.

There are also several places here in which you could build Hydro
generating plants with minimal impact on the existing surrounding
environment once it's built and running.
 
J

Joerg

Jan 1, 1970
0
MooseFET said:
[...]
[....]
The most environmentally friendly method is nuclear. It's also the
most reliable and generates the most output for its footprint.

We have yet to take a single power plant all the way through its life
cycle.
Until we do it for real , we can't say exactly how bad the problem of
getting
rid of the old plant will be. There is a lot of material that is just
radio
active enough to be trouble to make the question a hard one. If it
was just
the reactor core, the question would be a lot easier.

Oh, there have been. Then next one south of here:

http://www.nrc.gov/info-finder/deco...r/rancho-seco-nuclear-generating-station.html

[...]
 
J

Joerg

Jan 1, 1970
0
Hammy said:
The thing that kills me is that solar and wind aren't really
environmentally friendly! The amount of land required to generate even
modest amounts of energy is vast. The land has to be cleared roads
have to be built, equipment run in and out.

Nobody really knows what effect the large magnet field that those huge
wind turbines generate have on wildlife and people. The other thing is
it's unreliable.

The only reason it's gaining popularity is because governments are
handing out lucrative contracts and incentives to 21'st century snake
oil salesman to appease a bunch of uninformed people. Tell me what you
want to hear and pay me enough and I'll tell you.

The most environmentally friendly method is nuclear. It's also the
most reliable and generates the most output for its footprint.

There are also several places here in which you could build Hydro
generating plants with minimal impact on the existing surrounding
environment once it's built and running.


Both wind and solar can be very useful and put up in places where nobody
really cares. However, they must be paired with sunstantial buffer
capacity for when the wind doesn't blow and the sun doesn't shine, and
that's one of the largely unsolved issues. We don't have enough
high-mountain valleys even if we had them all dammed up for hydro storage.
 
K

krw

Jan 1, 1970
0
On Sat, 13 Feb 2010 07:46:11 -0800 (PST), MooseFET
We have yet to take a single power plant all the way through its life
cycle.

What a lie.

Decommissioned US commercial nuclear reactors (excluding experimental
reactors):
Connecticut Yankee
Maine Yankee
Shippingport
Shoreham
Yankee Rowe
Elk River
Zion
Fort Saint Vrain
Pathfinder
Rancho Seco
Trojan, Rainier

http://www.search.com/reference/List_of_nuclear_reactors
 
K

krw

Jan 1, 1970
0
Both wind and solar can be very useful and put up in places where nobody
really cares. However, they must be paired with sunstantial buffer
capacity for when the wind doesn't blow and the sun doesn't shine, and
that's one of the largely unsolved issues.

Oh, that issue has been solved. Unfortunately, it means that the cost
of the solar/wind generation is *IN ADDITION* to the cost of the more
reliable means. It does save some fuel cost but add tremendous
capital costs.
We don't have enough
high-mountain valleys even if we had them all dammed up for hydro storage.

The greenie's answer is "live in a cave".
 
K

krw

Jan 1, 1970
0
None have really been finished from the comments on Yankee Rowe
Nuclear Power Station
"However, over 100,000 pounds of spent fuel rods are still on-site,
contained in dry casks, built of concrete and steel. These will be
located at the site until the completion of the Yucca Mountain
disposal facility, around 2020."

It assumes that Yucca is built and really works as intended.

A purely political problem. IOW, you continue the lie.
 
K

krw

Jan 1, 1970
0
And His Royal Highness, the Ultimate Dipshit, Obama, has pulled Yucca
Mountain funding from the budget.

Of course. He wants no solution that doesn't double down on taxes. In
fact, he want's no solution but does want to double down. That's the
way of the tyrant.
 
D

D from BC

Jan 1, 1970
0
Imagine the no input ripple version of the transformer coupled SEPIC
circuit.
ie: there are 3 windings the third being the isolated output.
Now take the power MOSFET and replace it with a pair in series source
to source.

This circuit can be connected directly to the unrectified maines. It
makes
an isolated squarewavish wave form. This can then be run into a
sychronous
rectifier to make a DC output.

All this involves no diode drops from the mains to the DC output.


Neato :)
 
H

Hammy

Jan 1, 1970
0
Oh, that issue has been solved. Unfortunately, it means that the cost
of the solar/wind generation is *IN ADDITION* to the cost of the more
reliable means. It does save some fuel cost but add tremendous
capital costs.

How have they resolved this if there is no wind or sun you cannot
generate power from it therefore it isn't solar or wind generated
power.
 
H

Hammy

Jan 1, 1970
0
Both wind and solar can be very useful and put up in places where nobody
really cares. However, they must be paired with sunstantial buffer
capacity for when the wind doesn't blow and the sun doesn't shine, and
that's one of the largely unsolved issues. We don't have enough
high-mountain valleys even if we had them all dammed up for hydro storage.


That is my point it's not reliable.

You will always need 24/7 and neither can provide that.

The time and resources spent on this pipe dream could be better spent
on resolving issues with proven reliable technologies mainly I'm
talking nuclear; such as disposal of radioactive waste.

My point being short of an accident and waste disposal; nuclear
generation has a small negative environmental impact. Compare this to
using up a massive chunk of land to plant wind turbines or solar cells
with supporting infrastructure. Then to compound it say for two years
your ideal sun or wind location isn't so ideal. Then you have a field
with some really expensive lawn ornaments.

How much land would a wind or solar farm require to generate even 1/10
what one modern nuclear generation plant can generate?

I guess it keeps the environmentalist happy.
 
K

krw

Jan 1, 1970
0
How have they resolved this if there is no wind or sun you cannot
generate power from it therefore it isn't solar or wind generated
power.

By burning coal in the other power plant that also had to be built.
 
P

Paul E. Schoen

Jan 1, 1970
0
Hammy said:
That is my point it's not reliable.

You will always need 24/7 and neither can provide that.

The time and resources spent on this pipe dream could be better spent
on resolving issues with proven reliable technologies mainly I'm
talking nuclear; such as disposal of radioactive waste.

My point being short of an accident and waste disposal; nuclear
generation has a small negative environmental impact. Compare this to
using up a massive chunk of land to plant wind turbines or solar cells
with supporting infrastructure. Then to compound it say for two years
your ideal sun or wind location isn't so ideal. Then you have a field
with some really expensive lawn ornaments.

How much land would a wind or solar farm require to generate even 1/10
what one modern nuclear generation plant can generate?

I guess it keeps the environmentalist happy.

The ultimate solution is to reduce our unreasonable per-capita consumption
of energy, as well as reducing how many "capita" we must feed. This *will*
happen eventually, and possibly in our lifetimes. If we invest in renewable
energy, even if present yields are minimal and "unreliable", we will also
be promoting research into improvements, and we will be creating jobs that
can be performed by those with less education and training, with less
disastrous consequences if someone goofs up, or worse, goes berzerk and
actively initiates a calamity. So far, nuclear power plants have suffered
"accidents" which were mostly human error and not deliberate malice. As
people generally are "dumbing down" and/or becoming mentally unstable and
morally bankrupt, there is increasing risk of major problems in nuclear
facilities. They are designed with multiple safeguards and have been made
idiot-proof, but the world continues to evolve to produce better idiots.

We should invest more in "human engineering" to create (or recreate) truly
liveable cities and a social ethic that promotes cooperation rather than
the sort of competition that relies on unfair advantages and ruthless and
irresponsible business practices. The majority of the world's population
lives in extremely substandard conditions, while many of us in the US and
other more "developed" nations enjoy artificially inflated lifestyles based
on wasteful energy consumption and an economy that is unsustainable in the
long run.

Paul
 
P

Paul Keinanen

Jan 1, 1970
0
How have they resolved this if there is no wind or sun you cannot
generate power from it therefore it isn't solar or wind generated
power.

The sun shines and the wind blows somewhere on earth. Just connect the
sources with a sufficiently large grid. The cost of this grid should
be added to the cost of the unreliable sources.
 
J

Joerg

Jan 1, 1970
0
D said:

Except then you still have to replace the Schottky diode in the SEPIC
with a synchronously controlled FET circuit ;-)
 
K

krw

Jan 1, 1970
0
The sun shines and the wind blows somewhere on earth. Just connect the
sources with a sufficiently large grid. The cost of this grid should
be added to the cost of the unreliable sources.

If money were infinite I suppose you could build such a grid, too.
Otherwise it's as silly as using PV or wind to generate electricity.
 
K

krw

Jan 1, 1970
0
The ultimate solution is to reduce our unreasonable per-capita consumption
of energy,

Like I said earlier, the stupid greenies want us all to move into
caves.
as well as reducing how many "capita" we must feed.

You should be the first to kill yourself. Show us all the one, true,
way to salvation.
This *will*
happen eventually, and possibly in our lifetimes. If we invest in renewable
energy, even if present yields are minimal and "unreliable", we will also
be promoting research into improvements, and we will be creating jobs that
can be performed by those with less education and training, with less
disastrous consequences if someone goofs up, or worse, goes berzerk and
actively initiates a calamity. So far, nuclear power plants have suffered
"accidents" which were mostly human error and not deliberate malice. As
people generally are "dumbing down" and/or becoming mentally unstable and
morally bankrupt, there is increasing risk of major problems in nuclear
facilities. They are designed with multiple safeguards and have been made
idiot-proof, but the world continues to evolve to produce better idiots.

Can't be idiot-proof. You're still here.
We should invest more in "human engineering" to create (or recreate) truly
liveable cities and a social ethic that promotes cooperation rather than
the sort of competition that relies on unfair advantages and ruthless and
irresponsible business practices. The majority of the world's population
lives in extremely substandard conditions, while many of us in the US and
other more "developed" nations enjoy artificially inflated lifestyles based
on wasteful energy consumption and an economy that is unsustainable in the
long run.

....as long as you're in charge, everything will be just fin, right?
 
K

krw

Jan 1, 1970
0
My sig says it all...

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

The Green Police are like watermelons...
GREEN on the outside, RED on the inside.
Test them as done in "Day of the Jackal"

How about doing a Gallagher on them?
 
P

Paul E. Schoen

Jan 1, 1970
0
Jim Thompson said:
My sig says it all...

We don't need green police. Mother nature is the ultimate enforcer of the
laws of physics and economics. More frequent disasters such as the
earthquake in Haiti and the AGW-induced record snowfalls in the Eastern US
are just a taste of what is still to come. Our economies are strained and
faltering as we attempt to clean up and return to the relative normalcy we
had before, and our resources are quickly depleting as we seek to extract
more fossil-fuel energy by waging war on foreign powers.

And indirectly we are waging war on our own people by creating an unhealthy
environment. We have not properly cleaned up for even the Exxon-Valdez oil
spill, and the real damages to the people affected were never repaid while
Exxon-Mobil reaped record profits. The common people of New Orleans have
not recovered from their tragic disaster. Most Americans have suffered
permanent economic setbacks because of greed and irresponsibility of
government and big business. And the majority of the world's population are
rightfully jealous of those who flaunt their lavish lifestyles.

Being green is just the right thing to do. But at this point it may be just
a personal decision of ethics and morality, and gratuitous opposition by
those who smugly think they know it all will defer any hope of effective
change until it is too late, as it may be already.

Don't worry about the Earth. Our planet and natural phenomena have
eliminated other species before, and no doubt humans will be similarly
eradicated by our own hand or by events too powerful for our technology to
control, and those few who may survive will revert to living in caves.

Paul
 
L

legg

Jan 1, 1970
0
My offline smps design has 3 parts making the most heat.
A power diode, a mosfet and a bridge rectifier.

I'm interested in any cookbook designs that replaces a bridge rectifier.
Any pointers?

In terms of rectification efficiency alone, the doubler has only one
rectifier in the current path. There are other advantages that
shouldn't be ignored for lower voltage mains. If you're doing PFC, you
should check some of the actual requirements, in light of the
performance of low frequency switched doublers.

Above 80V and at low frequency, average-current-sensitive rectifiers
still have the advantage over active fet rms-sensitive substitutes.
One trick is to make the bridge do inrush limiting duty, removing
losses from that function, at the temperature derating required for
scrs.

Simple low frequency rectifiers are more efficient when running hot,
so whatever the losses end up being, don't be so anxious to keep this
part cool, just make sure it doesn't infect other less rugged parts in
the neighbourhood.

RL
 
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