http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently
they used to be found at some sub-stations back in the 60's to 70's).

newshound explained :
http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently they
used to be found at some sub-stations back in the 60's to 70's).

Why head it with a photo of a turbine?

On Mon, 15 Feb 2021 23:11:40 +0000, Harry Bloomfield, Esq. wrote:

newshound explained :
http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently
they used to be found at some sub-stations back in the 60's to 70's).

Why head it with a photo of a turbine?


Because that is the heart of the inertial system that has to be supported
when adding solar, wind and wave energy.

On 16/02/2021 05:33, jon wrote:
On Mon, 15 Feb 2021 23:11:40 +0000, Harry Bloomfield, Esq. wrote:

newshound explained :
http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently
they used to be found at some sub-stations back in the 60's to 70's).

Why head it with a photo of a turbine?


Because that is the heart of the inertial system that has to be supported
when adding solar, wind and wave energy.

And batteries and interconnectors. In short anything DC that feeds the
grid via an inverter.


--
€œI know that most men, including those at ease with problems of the
greatest complexity, can seldom accept even the simplest and most
obvious truth if it be such as would oblige them to admit the falsity of
conclusions which they have delighted in explaining to colleagues, which
they have proudly taught to others, and which they have woven, thread by
thread, into the fabric of their lives.€�

ۥ Leo Tolstoy

Yes well I have no real idea how all generating gear can be synchronised
either. Seems a trifle crude but then I guess getting it wrong could be
rather nasty, so how is it done when they import power from other countries,
how do they go about deciding who needs to synchronise to whom?
Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"jon" wrote in message ...
On Mon, 15 Feb 2021 23:11:40 +0000, Harry Bloomfield, Esq. wrote:

newshound explained :
http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently
they used to be found at some sub-stations back in the 60's to 70's).

Why head it with a photo of a turbine?


Because that is the heart of the inertial system that has to be supported
when adding solar, wind and wave energy.

Brian Gaff wrote:

Yes well I have no real idea how all generating gear can be synchronised
either. Seems a trifle crude but then I guess getting it wrong could be
rather nasty, so how is it done when they import power from other countries,
how do they go about deciding who needs to synchronise to whom?

You either have a fully synchronised grid covering a continent (remember
how serbia/kosovo were causing all european mains to run slow a wile back?)

Or you link them using HVDC, and then you don't need to sync.

On 16/02/2021 11:52, Chris Hogg wrote:
On Mon, 15 Feb 2021 21:35:04 +0000, newshound
wrote:

http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently
they used to be found at some sub-stations back in the 60's to 70's).

While I think I understand what they do, why are they called
condensers?

My guess is that it is because they 'store a little electrical energy'...

--
"The most difficult subjects can be explained to the most slow witted
man if he has not formed any idea of them already; but the simplest
thing cannot be made clear to the most intelligent man if he is firmly
persuaded that he knows already, without a shadow of doubt, what is laid
before him."

- Leo Tolstoy

On 16/02/2021 11:52, Chris Hogg wrote:
On Mon, 15 Feb 2021 21:35:04 +0000, newshound
wrote:

http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently
they used to be found at some sub-stations back in the 60's to 70's).

While I think I understand what they do, why are they called
condensers?

I guess it is a historic term. Presumably they shift the phase in the
opposite direction to inductors.

On 16/02/2021 11:52, Chris Hogg wrote:
On Mon, 15 Feb 2021 21:35:04 +0000, newshound
wrote:

http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently
they used to be found at some sub-stations back in the 60's to 70's).

While I think I understand what they do, why are they called
condensers?


Dates back to the 18th century when electric fluid was condensed in a
device (typically 2 plates and an insulator).

--
Robin
reply-to address is (intended to be) valid

The Natural Philosopher wrote:
On 16/02/2021 11:52, Chris Hogg wrote:
On Mon, 15 Feb 2021 21:35:04 +0000, newshound
wrote:

http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently
they used to be found at some sub-stations back in the 60's to 70's).

While I think I understand what they do, why are they called
condensers?

My guess is that it is because they 'store a little electrical energy'...


It's a phase angle thing, not particularly for energy storage.

They build them to stop people from smoking. This one is "hydrogen cooled".
The perfect choice in a cooling gas. One thing I like about devices
like this, is the stairwells are always designed so you can't
get away in a hurry :-)

https://upload.wikimedia.org/wikiped...ondenser_1.jpg

It's a big beautiful machine (as my instructor used to say).
This picture shows what's inside the metalwork of the previous picture.

https://www.theengineeringknowledge....-1-768x737.jpg

It creates leading or lagging VARs. Via a phaser diagram, you
add the effects of it, to whatever the rest of your "plant" is doing.

Too many of those 0.7PF LED lamps, and you'll be needing
one of those. It could become a requirement, simply by
switching from incandescent lamps to LED lamps or CCFLs.
The LED lamps are getting cheaper, but are also
having lousier PF values now. The incandescent lamps
drew only watts and no VARs. The power company might
need to buy another one of those, to balance out all
your LED lamps.

Since big industries are billed for both real and
reactive power, it's the kind of device you might use
to solve your reactive power problem (balance it out).
If your plant is leading, the machine can be set to
lagging to compensate. And vice versa, until the
thing saturates. There's usually one side of the
graph where bad things happen (and that's why it
needs the fancy cooling).

https://www.theengineeringknowledge....er-V-Curve.jpg

The generator at the power plant, also has excitation
control, and can be adjusted, but of the two directions
leading and lagging, it can only safely provide about
a 5% correction in one of the directions. It gets a bit
warm if pushed too far in one direction. That's why
the network as a whole, has capacitor banks at strategic
locations. Like, if some industry creates a reactive power
problem locally where it is connected to the grid, by
"billing them for it", it gives an incentive for them
to provide a capacitor bank or a synchronous condenser
on their own property.

The synchronous condenser, being a moving machine,
probably needs some serious maintenance every ten
years or so. As that's how long some of the motor-generator
sets last (the ones that create three phase power from
a single phase supply).

The device pictured in the Wikipedia article, is "big
enough for around four major industrial sites of the
same type". Since it's that big, it is probably owned
by the power company and used for grid stability maintenance.
And via "billing for reactive power", that's how they
pay for the nuisance installation of such. Someone
has to build it, and there is a financial incentive
for the person making the mess, to install one.
Ultimately, the power company is responsible for
grid stability, and has to "correct" whatever "mess"
the customers make. If you expect "X" MVARs in an
industrial park, eventually someone has to fork out
to buy compensation for it.

Consumers don't necessarily get billed for reactive,
and the correction of what consumers do, is a "freebie".
All that the simple meters with the rotating plate did, was
measure real power (watts) and not VARs.

Note that this may not stay that way forever - those
nice smart meters you got, give the perfect means
of billing for both real and reactive power. It's easy
with the sigma-delta converters in there and that little
processor in the meter, doing the maths, to compute
your current VAR load.

Paul

On 16/02/2021 13:57, Paul wrote:

Explanation snipped

Thanks for that.

--
Cheers
Clive

Andy Burns wrote:
Brian Gaff wrote:

Yes well I have no real idea how all generating gear can be synchronised
either. Seems a trifle crude but then I guess getting it wrong could be
rather nasty, so how is it done when they import power from other
countries,
how do they go about deciding who needs to synchronise to whom?

You either have a fully synchronised grid covering a continent (remember
how serbia/kosovo were causing all european mains to run slow a wile back?)

Or you link them using HVDC, and then you don't need to sync.

And you see in the news today, that Texas is screwed right now, because
it's not integrated into the rest of the grid. They live or die, on
the power they create locally for themselves. And they're doing
blackouts at the moment. The "ERCOT" in the picture here, is
the island that does not have sufficient internal generating
capacity at the moment. They did this, as a means to avoid
federal regulation of their power by FERC.

https://en.wikipedia.org/wiki/Wide_a...le:Nercmap.JPG

There's a lot of this going around. These power islands are all over the place.

https://en.wikipedia.org/wiki/Wide_a...ricityUCTE.svg

Power islands are clever, except when you don't have enough power.

Paul

On 16/02/2021 14:12, Clive Arthur wrote:
On 16/02/2021 13:57, Paul wrote:

Explanation snipped

Thanks for that.

+1

On 16/02/2021 13:51, Robin wrote:
On 16/02/2021 11:52, Chris Hogg wrote:
On Mon, 15 Feb 2021 21:35:04 +0000, newshound
wrote:

http://watt-logic.com/2021/02/15/synchronous-condenser/

A bit of technology I had not come across before (although apparently
they used to be found at some sub-stations back in the 60's to 70's).

While I think I understand what they do, why are they called
condensers?


Dates back to the 18th century when electric fluid was condensed in a
device (typically 2 plates and an insulator).

The good old Leyden jar!

On 16 Feb 2021 at 14:50:21 GMT, "newshound"
wrote:

On 16/02/2021 14:12, Clive Arthur wrote:
On 16/02/2021 13:57, Paul wrote:

Explanation snipped

Thanks for that.

+1

Thirded. But I really cannot stop myself quibbling about reactive "power",
though I suspect you didn't mean it.

--
Roger Hayter

On Tue, 16 Feb 2021 09:20:47 -0500, Paul wrote:

Andy Burns wrote:
Brian Gaff wrote:

Yes well I have no real idea how all generating gear can be
synchronised either. Seems a trifle crude but then I guess getting it
wrong could be rather nasty, so how is it done when they import power
from other countries,
how do they go about deciding who needs to synchronise to whom?

You either have a fully synchronised grid covering a continent
(remember how serbia/kosovo were causing all european mains to run slow
a wile back?)

Or you link them using HVDC, and then you don't need to sync.

And you see in the news today, that Texas is screwed right now, because
it's not integrated into the rest of the grid. They live or die, on the
power they create locally for themselves. And they're doing blackouts at
the moment. The "ERCOT" in the picture here, is the island that does not
have sufficient internal generating capacity at the moment. They did
this, as a means to avoid federal regulation of their power by FERC.

https://en.wikipedia.org/wiki/Wide_a...s_grid#/media/
File:Nercmap.JPG

There's a lot of this going around. These power islands are all over the
place.

https://en.wikipedia.org/wiki/Wide_a...s_grid#/media/
File:ElectricityUCTE.svg

Power islands are clever, except when you don't have enough power.

Paul

It's better to have a central power grid with all power stations piped
into it.

Roger Hayter wrote:
On 16 Feb 2021 at 14:50:21 GMT, "newshound"
wrote:

On 16/02/2021 14:12, Clive Arthur wrote:
On 16/02/2021 13:57, Paul wrote:

Explanation snipped

Thanks for that.

+1

Thirded. But I really cannot stop myself quibbling about reactive "power",
though I suspect you didn't mean it.


The units of measure are volt-ampere-reactive.

To quote the instructor "reactive power sloshes around in the network,
between the load and the generator". The current flow makes some
of the conductors warmer as a result. It's not consumed as such.

https://energyinnovationproject.com/...eactive-power/

"Reactive power - the delay between voltage and current at a given point - is
subjected to transmission constraints. As a result, it is often necessary to
produce reactive power close to the location where it is needed."

To carry reactive power, you still need the wire size for it. That's
the transmission constraint.

Paul

On 16/02/2021 19:18, Paul wrote:
Roger Hayter wrote:
On 16 Feb 2021 at 14:50:21 GMT, "newshound"
wrote:

On 16/02/2021 14:12, Clive Arthur wrote:
Â*On 16/02/2021 13:57, Paul wrote:

Â*Explanation snipped

Â*Thanks for that.

+1

Thirded.Â* But I really cannot stop myself quibbling about reactive
"power",
though I suspect you didn't mean it.


The units of measure are volt-ampere-reactive.

To quote the instructor "reactive power sloshes around in the network,
between the load and the generator". The current flow makes some
of the conductors warmer as a result. It's not consumed as such.

https://energyinnovationproject.com/...eactive-power/


Â*Â* "Reactive power - the delay between voltage and current at a given
point - is
Â*Â*Â* subjected to transmission constraints. As a result, it is often
necessary to
Â*Â*Â* produce reactive power close to the location where it is needed."

To carry reactive power, you still need the wire size for it. That's
the transmission constraint.

Â*Â* Paul

Perhaps another example might be helpful. Most of the UK first
generation civil nuclear reactors (Magnox) had to be down-rated after
the discovery of unexpected corrosion problems. So the generators were
operating at somewhat below their original design conditions. This meant
that the copper windings in the rotor and stator were thicker than they
needed to be. This in turn meant that they could be operated so as to
generate extra "reactive power". Although the volts and amps are a bit
out of phase, the resistive heating in the windings is just related to
the current; thicker windings mean they can carry more current, and
hence export MegaVARs as well as Megawatts, helping to contribute to
grid stability. Under the original pool system I don't think MegaVARs
were actually traded, there was some sort of fudged "Ancilliary
Services" payment. I believe that under NETA MVars are traded similarly
to MW.

On 16/02/2021 17:48, jon wrote:
On Tue, 16 Feb 2021 09:20:47 -0500, Paul wrote:

Andy Burns wrote:
Brian Gaff wrote:

Yes well I have no real idea how all generating gear can be
synchronised either. Seems a trifle crude but then I guess getting it
wrong could be rather nasty, so how is it done when they import power
from other countries,
how do they go about deciding who needs to synchronise to whom?

You either have a fully synchronised grid covering a continent
(remember how serbia/kosovo were causing all european mains to run slow
a wile back?)

Or you link them using HVDC, and then you don't need to sync.

And you see in the news today, that Texas is screwed right now, because
it's not integrated into the rest of the grid. They live or die, on the
power they create locally for themselves. And they're doing blackouts at
the moment. The "ERCOT" in the picture here, is the island that does not
have sufficient internal generating capacity at the moment. They did
this, as a means to avoid federal regulation of their power by FERC.

https://en.wikipedia.org/wiki/Wide_a...s_grid#/media/
File:Nercmap.JPG

There's a lot of this going around. These power islands are all over the
place.

https://en.wikipedia.org/wiki/Wide_a...s_grid#/media/
File:ElectricityUCTE.svg

Power islands are clever, except when you don't have enough power.

Paul

It's better to have a central power grid with all power stations piped
into it.

This depends on scale.

From Wikipedia:

"The electrical power grid that powers North America is not a single
grid, but is instead divided into multiple wide area synchronous grids."

Russia has a single grid, China has two.

newshound wrote:
On 16/02/2021 17:48, jon wrote:
On Tue, 16 Feb 2021 09:20:47 -0500, Paul wrote:

Andy Burns wrote:
Brian Gaff wrote:

Yes well I have no real idea how all generating gear can be
synchronised either. Seems a trifle crude but then I guess getting it
wrong could be rather nasty, so how is it done when they import power
from other countries,
how do they go about deciding who needs to synchronise to whom?

You either have a fully synchronised grid covering a continent
(remember how serbia/kosovo were causing all european mains to run slow
a wile back?)

Or you link them using HVDC, and then you don't need to sync.

And you see in the news today, that Texas is screwed right now, because
it's not integrated into the rest of the grid. They live or die, on the
power they create locally for themselves. And they're doing blackouts at
the moment. The "ERCOT" in the picture here, is the island that does not
have sufficient internal generating capacity at the moment. They did
this, as a means to avoid federal regulation of their power by FERC.

https://en.wikipedia.org/wiki/Wide_a...s_grid#/media/
File:Nercmap.JPG

There's a lot of this going around. These power islands are all over the
place.

https://en.wikipedia.org/wiki/Wide_a...s_grid#/media/
File:ElectricityUCTE.svg

Power islands are clever, except when you don't have enough power.

Paul

It's better to have a central power grid with all power stations piped
into it.

This depends on scale.

From Wikipedia:

"The electrical power grid that powers North America is not a single
grid, but is instead divided into multiple wide area synchronous grids."

Russia has a single grid, China has two.

One of the reasons for not gridding excessively large areas
with AC transmission systems, is solar flares.

We had some sort of long line here, knocked out by a solar flare.
I don't remember any details though, it was likely a while ago.

You could distribute power with HVDC setups, but who knows,
maybe solar flares take those out by induction too. Maybe you'd
have to raise the rating of the line, to make it more flare-proof.

The news reporting on solar flares has been quiet for some time.

It's possible the HVDC setups are a bit on the expensive side,
but they are still building new ones. The East Coast of Canada
has a hydro project underway, where a certain "fixed link" between
provinces was run in reverse, the link being finished before
the generators were online, and an event came up where
reversing the flow was a distinct advantage. There's nothing
like having spare wires sitting around in an emergency (just
ask Texas :-) ).

This is why having an "energy basket" and diversifying is so
important. I don't think Texas missed that, but it's possible
they scheduled a bit too much down-time for their resources
at a bad moment. Nuclear reactors are great, but some of them
don't stay online as much as they should (60% uptime means
you have to "buy two to get one"). That's why one of the
design objectives for a paper design here, aims for 90%.
Then of course, reality kicks in, and some lower number
is the result (refurbs always seem to take a long time).
The Candu reactors here, can be fueled while they're
running, by a robot. Which protects the uptime a bit.

Paul

On 16/02/2021 20:12, newshound wrote:
On 16/02/2021 17:48, jon wrote:



It's better to have a central power grid with all power stations piped
into it.

This depends on scale.

From Wikipedia:

"The electrical power grid that powers North America is not a single
grid, but is instead divided into multiple wide area synchronous grids."

Russia has a single grid, China has two.

As with most things, the simple one dimensional thinking of the Art
Student - 'A is better than B' - is inadequate.

1. Large area grids are good because one part can prop up another part
in extreme conditions leading to lower overall cost.

2. Large area AC grids are not effective because the time delays over
the network start to impact on efficiency

3. Large area DC grids are starting to sort of happen.

4. If the large area grid cannot be split then under fault conditions it
all goes down together

Its the old EU argument for freedom of movement. Like the Titanic, who
needs watertight doors that restrict passenger movement? Until you have
a hole in the side of the ship...or a pandemic, or unlimited hostile
immigration




--
"I am inclined to tell the truth and dislike people who lie consistently.
This makes me unfit for the company of people of a Left persuasion, and
all women"