Mains power voltage drop to reduce usage?...

[Commander Kinsey]

On Tue, 22 Nov 2022 19:52:08 -0000, SteveW <steve@walker-family.me.uk> wrote:

On 19/11/2022 07:20, Commander Kinsey wrote:
On Thu, 17 Nov 2022 23:02:30 -0000, SteveW <steve@walker-family.me.uk
wrote:

On 17/11/2022 19:22, Scott Lurndal wrote:
SteveW <steve@walker-family.me.uk> writes:
On 17/11/2022 19:03, Commander Kinsey wrote:

Yes, the European mainland grid whilst it is not all of Europe, is
synchronised.
I believe Norway, the UK and Ireland, are definietly totally
separate.

I thought there was a problem with capacitance sending AC a long
distance, hence DC to the UK? Yet they\'re managing AC throughout most
of Europe?

They\'re not having to send it undersea though.

https://en.wikipedia.org/wiki/HVDC_Gotland

Except of course that that is DC link - because it is underwater.

Underwater is irrelevant, it\'s the capacitance in the wire.

It is not irrelevant at all. Overhead, high-voltage wires are
uninsulated. Underwater ones cannot be and also have to have physical
(metal)

Or any other hard substance.

> protection. That alone turns them into very long capacitors.

Make the insulater thicker?

Or what if you let the sea be the live voltage?

Or we could send a fucking powerfull laser beam through the air....

 

[Peeler]

On Tue, 22 Nov 2022 19:52:08 +0000, SteveWanker, another troll-feeding
senile ASSHOLE, blathered:

> It is not irrelevant at all.

What IS relevant though is that you senile ASSHOLES keep feeding the
trolling sociopath and attention whore, even though you senile ASSHOLES
already KNOW by now what he is all about! Right, senile ASSHOLE? <G>

 

[John Larkin]

On Tue, 22 Nov 2022 19:20:16 -0000, \"Commander Kinsey\"
<CK1@nospam.com> wrote:

On Tue, 22 Nov 2022 15:38:21 -0000, Clive Page <usenet@page2.eu> wrote:

On 18/11/2022 12:04, Martin Brown wrote:

I think they probably could increase the low frequency bound for domestic and modest sized solar or wind farms not to drop off grid. It is preferable to stress a few motors and transformers for a few minutes when compared to the major cost of dropping large segments of load.

Otherwise you get the cascade failure mode that afflicted the UK after a freak lightning strike took out a fairly small electric plant and caused a cascade of failures that took down mains for London and much of England.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836626/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf

It didn\'t help that electric trains required an engineering reset before they could be moved from where they ground to a halt when the mains went down.

It turned out **that** the design spec of the trains was **that** they should cope with a frequency drop to as low as 49 Hz

Why do people put \"that\" everywhere? Retry your sentence without \"that\" in the two instances marked. No change in meaning whatsoever.

but they were built by German engineers who assumed that in a modern country like Germany, but not as it turned out the UK, the mains frequency could *never* drop below 49.5 Hz, so they built in (or failed to avoid) a serious failure mode when this actually occurred. Hence all their class 700 trains stopped.

Surely a failure mode is one where the motor would have been damaged? Why make it fail before it has to?

Messrs Thameslink, the train operator, compounded the problem by only installing in some of their trains a software update which would have allowed the driver to restart the train after it had stopped from this cause.

Why on earth would anyone not give the driver such an ability? Imagine if you had to call someone out because you stalled your car.

Since only a few trains could be restarted, the lines were still pretty well blocked, and the network was effectively at a standstill for about half a day. A combined German and British cock-up you might think.

The whole idea of running things on rails is preposterous. You can\'t go round a broken down vehicle, and you can\'t stop in a sensible time if a lorry has broken down crossing the track.

But rails bear enormous loads and trains are very efficient.

 

[John Larkin]

On Tue, 22 Nov 2022 19:52:08 +0000, SteveW <steve@walker-family.me.uk>
wrote:

On 19/11/2022 07:20, Commander Kinsey wrote:
On Thu, 17 Nov 2022 23:02:30 -0000, SteveW <steve@walker-family.me.uk
wrote:

On 17/11/2022 19:22, Scott Lurndal wrote:
SteveW <steve@walker-family.me.uk> writes:
On 17/11/2022 19:03, Commander Kinsey wrote:

Yes, the European mainland grid whilst it is not all of Europe, is
synchronised.
I believe Norway, the UK and Ireland, are definietly totally
separate.

I thought there was a problem with capacitance sending AC a long
distance, hence DC to the UK?  Yet they\'re managing AC throughout most
of Europe?

They\'re not having to send it undersea though.

https://en.wikipedia.org/wiki/HVDC_Gotland

Except of course that that is DC link - because it is underwater.

Underwater is irrelevant, it\'s the capacitance in the wire.

It is not irrelevant at all. Overhead, high-voltage wires are
uninsulated. Underwater ones cannot be and also have to have physical
(metal) protection. That alone turns them into very long capacitors.

Transmission lines, actually.

\"Transmission lines\" in the electronic meaning, with a characteristic
impedance, not just capacitance.

 

[Peeler]

On Tue, 22 Nov 2022 13:06:22 -0800, John Larkin, another mentally deficient,
troll-feeding, senile ASSHOLE, blathered:

> But rails bear enormous loads and trains are very efficient.

Isn\'t your unwashed wanker\'s cock all sore by now what with all your hard
sucking, you sick senile asshole?

 

[Commander Kinsey]

On Tue, 22 Nov 2022 21:06:22 -0000, John Larkin <jlarkin@highlandsnipmetechnology.com> wrote:

On Tue, 22 Nov 2022 19:20:16 -0000, \"Commander Kinsey\"
CK1@nospam.com> wrote:

On Tue, 22 Nov 2022 15:38:21 -0000, Clive Page <usenet@page2.eu> wrote:

On 18/11/2022 12:04, Martin Brown wrote:

I think they probably could increase the low frequency bound for domestic and modest sized solar or wind farms not to drop off grid. It is preferable to stress a few motors and transformers for a few minutes when compared to the major cost of dropping large segments of load.

Otherwise you get the cascade failure mode that afflicted the UK after a freak lightning strike took out a fairly small electric plant and caused a cascade of failures that took down mains for London and much of England.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836626/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf

It didn\'t help that electric trains required an engineering reset before they could be moved from where they ground to a halt when the mains went down.

It turned out **that** the design spec of the trains was **that** they should cope with a frequency drop to as low as 49 Hz

Why do people put \"that\" everywhere? Retry your sentence without \"that\" in the two instances marked. No change in meaning whatsoever.

but they were built by German engineers who assumed that in a modern country like Germany, but not as it turned out the UK, the mains frequency could *never* drop below 49.5 Hz, so they built in (or failed to avoid) a serious failure mode when this actually occurred. Hence all their class 700 trains stopped.

Surely a failure mode is one where the motor would have been damaged? Why make it fail before it has to?

Messrs Thameslink, the train operator, compounded the problem by only installing in some of their trains a software update which would have allowed the driver to restart the train after it had stopped from this cause.

Why on earth would anyone not give the driver such an ability? Imagine if you had to call someone out because you stalled your car.

Since only a few trains could be restarted, the lines were still pretty well blocked, and the network was effectively at a standstill for about half a day. A combined German and British cock-up you might think.

The whole idea of running things on rails is preposterous. You can\'t go round a broken down vehicle, and you can\'t stop in a sensible time if a lorry has broken down crossing the track.

But rails bear enormous loads and trains are very efficient.

Actually, they use more fuel per passenger than a car.

 

[Peeler]

On Tue, 22 Nov 2022 13:08:45 -0800, John Larkin, another mentally deficient,
troll-feeding, senile ASSHOLE, blathered:

Transmission lines, actually.

\"Transmission lines\" in the electronic meaning, with a characteristic
impedance, not just capacitance.

Will you keep your endless senile shit out of these groups finally, you
useless senile shithead?

 

[whit3rd]

On Tuesday, November 22, 2022 at 2:08:37 PM UTC-8, Commander Kinsey wrote:

On Tue, 22 Nov 2022 21:06:22 -0000, John Larkin <jla...@highlandsnipmetechnology.com> wrote:

On Tue, 22 Nov 2022 19:20:16 -0000, \"Commander Kinsey\"
C...@nospam.com> wrote:

The whole idea of running things on rails is preposterous. You can\'t go round a broken down vehicle, and you can\'t stop in a sensible time if a lorry has broken down crossing the track.

So, tracks need overpass or underpass for most road crossings.
And, faltering trains need to get off the main tracks somehow (sidings, the
provisions are called). There\'s always solutions to problems.

But rails bear enormous loads and trains are very efficient.

Actually, they use more fuel per passenger than a car.

Which is a kind of waste of resources? But, the man-hours of time available to
passengers because they don\'t have to steer, brake, etc. is a major savings.
Goods and materials traveling via train are effectively reducing road wear, congestion, and
travel time a LOT just by spreading goods from their point-of-production.

An old diary entry told of a couple who wanted to enjoy some cream, who had
the servants take them by carriage to a dairy... ice cream is available at all our
little groceries because we do NOT need to buy local.

 

[Carlos E.R.]

On 2022-11-22 19:10, The Natural Philosopher wrote:

On 22/11/2022 16:32, John Larkin wrote:
On Tue, 22 Nov 2022 15:38:21 +0000, Clive Page <usenet@page2.eu
wrote:

On 18/11/2022 12:04, Martin Brown wrote:

I think they probably could increase the low frequency bound for
domestic and modest sized solar or wind farms not to drop off grid.
It is preferable to stress a few motors and transformers for a few
minutes when compared to the major cost of dropping large segments
of load.

Otherwise you get the cascade failure mode that afflicted the UK
after a freak lightning strike took out a fairly small electric
plant and caused a cascade of failures that took down mains for
London and much of England.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836626/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf

It didn\'t help that electric trains required an engineering reset
before they could be moved from where they ground to a halt when the
mains went down.

It turned out that the design spec of the trains was that they should
cope with a frequency drop to as low as 49 Hz, but they were built by
German engineers who assumed that in a modern country like Germany,
but not as it turned out the UK, the mains frequency could *never*
drop below 49.5 Hz, so they built in (or failed to avoid) a serious
failure mode when this actually occurred.  Hence all their class 700
trains stopped.

Messrs Thameslink, the train operator, compounded the problem by only
installing in some of their trains a software update which would have
allowed the driver to restart the train after it had stopped from
this cause.  Since only a few trains could be restarted, the lines
were still pretty well blocked, and the network was effectively at a
standstill for about half a day.  A combined German and British
cock-up you might think.

I can\'t imagine anything that would cause a reasonable train
propulsion system to fail at 49 Hz, or even 45 Hz.

Software. They designed it to work at exactly 50Hz, and instead of
designing it to also work at 49.5Hz, they simply flagged an error and
refused to start until manually reset.

Probably the programers where given those specs.

IIRC these are all massive brushless motors running off rectified DC
with chopper inverters feeding the coils.  So no reason to behave this
way except lazy programming by a crap German software engineer.

--
Cheers, Carlos.

 

[Carlos E.R.]

On 2022-11-22 23:08, Commander Kinsey wrote:

On Tue, 22 Nov 2022 21:06:22 -0000, John Larkin
jlarkin@highlandsnipmetechnology.com> wrote:

On Tue, 22 Nov 2022 19:20:16 -0000, \"Commander Kinsey\"
CK1@nospam.com> wrote:

On Tue, 22 Nov 2022 15:38:21 -0000, Clive Page <usenet@page2.eu> wrote:

On 18/11/2022 12:04, Martin Brown wrote:

I think they probably could increase the low frequency bound for
domestic and modest sized solar or wind farms not to drop off grid.
It is preferable to stress a few motors and transformers for a few
minutes when compared to the major cost of dropping large segments
of load.

Otherwise you get the cascade failure mode that afflicted the UK
after a freak lightning strike took out a fairly small electric
plant and caused a cascade of failures that took down mains for
London and much of England.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836626/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf

It didn\'t help that electric trains required an engineering reset
before they could be moved from where they ground to a halt when
the mains went down.

It turned out **that** the design spec of the trains was **that**
they should cope with a frequency drop to as low as 49 Hz

Why do people put \"that\" everywhere?  Retry your sentence without
\"that\" in the two instances marked. No change in meaning whatsoever.

but they were built by German engineers who assumed that in a modern
country like Germany, but not as it turned out the UK, the mains
frequency could *never* drop below 49.5 Hz, so they built in (or
failed to avoid) a serious failure mode when this actually
occurred.  Hence all their class 700 trains stopped.

Surely a failure mode is one where the motor would have been
damaged?  Why make it fail before it has to?

Messrs Thameslink, the train operator, compounded the problem by
only installing in some of their trains a software update which
would have allowed the driver to restart the train after it had
stopped from this cause.

Why on earth would anyone not give the driver such an ability?
Imagine if you had to call someone out because you stalled your car.

Since only a few trains could be restarted, the lines were still
pretty well blocked, and the network was effectively at a standstill
for about half a day.  A combined German and British cock-up you
might think.

The whole idea of running things on rails is preposterous.  You can\'t
go round a broken down vehicle, and you can\'t stop in a sensible time
if a lorry has broken down crossing the track.

But rails bear enormous loads and trains are very efficient.

Actually, they use more fuel per passenger than a car.

Not true.

--
Cheers, Carlos.

 

[John Larkin]

On Tue, 22 Nov 2022 22:08:29 -0000, \"Commander Kinsey\"
<CK1@nospam.com> wrote:

On Tue, 22 Nov 2022 21:06:22 -0000, John Larkin <jlarkin@highlandsnipmetechnology.com> wrote:

On Tue, 22 Nov 2022 19:20:16 -0000, \"Commander Kinsey\"
CK1@nospam.com> wrote:

On Tue, 22 Nov 2022 15:38:21 -0000, Clive Page <usenet@page2.eu> wrote:

On 18/11/2022 12:04, Martin Brown wrote:

I think they probably could increase the low frequency bound for domestic and modest sized solar or wind farms not to drop off grid. It is preferable to stress a few motors and transformers for a few minutes when compared to the major cost of dropping large segments of load.

Otherwise you get the cascade failure mode that afflicted the UK after a freak lightning strike took out a fairly small electric plant and caused a cascade of failures that took down mains for London and much of England.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836626/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf

It didn\'t help that electric trains required an engineering reset before they could be moved from where they ground to a halt when the mains went down.

It turned out **that** the design spec of the trains was **that** they should cope with a frequency drop to as low as 49 Hz

Why do people put \"that\" everywhere? Retry your sentence without \"that\" in the two instances marked. No change in meaning whatsoever.

but they were built by German engineers who assumed that in a modern country like Germany, but not as it turned out the UK, the mains frequency could *never* drop below 49.5 Hz, so they built in (or failed to avoid) a serious failure mode when this actually occurred. Hence all their class 700 trains stopped.

Surely a failure mode is one where the motor would have been damaged? Why make it fail before it has to?

Messrs Thameslink, the train operator, compounded the problem by only installing in some of their trains a software update which would have allowed the driver to restart the train after it had stopped from this cause.

Why on earth would anyone not give the driver such an ability? Imagine if you had to call someone out because you stalled your car.

Since only a few trains could be restarted, the lines were still pretty well blocked, and the network was effectively at a standstill for about half a day. A combined German and British cock-up you might think.

The whole idea of running things on rails is preposterous. You can\'t go round a broken down vehicle, and you can\'t stop in a sensible time if a lorry has broken down crossing the track.

But rails bear enormous loads and trains are very efficient.

Actually, they use more fuel per passenger than a car.

In the USA, people travel long distances (and we sure have long
distances) by air. The speed ratio is around 10:1.

Trains mostly move freight and products. The fuel cost of a train is
around 1/3 to 1/4 the cost of using trucks. There is a big savings on
labor too. A single freight train can replace several hundred trucks.

The U.S. freight rail network is about 140,000 miles.

Trains are far safer for hazmat transport compared to trucks. 10:1 is
quoted.

 

[Mike Monett VE3BTI]

whit3rd <whit3rd@gmail.com> wrote:

On Tuesday, November 22, 2022 at 2:08:37 PM UTC-8, Commander Kinsey
wrote:
On Tue, 22 Nov 2022 21:06:22 -0000, John Larkin
jla...@highlandsnipmetechnology.com> wrote:

On Tue, 22 Nov 2022 19:20:16 -0000, \"Commander Kinsey\"
C...@nospam.com> wrote:

The whole idea of running things on rails is preposterous. You can\'t
go round a broken down vehicle, and you can\'t stop in a sensible
time if a lorry has broken down crossing the track.

So, tracks need overpass or underpass for most road crossings.
And, faltering trains need to get off the main tracks somehow (sidings,
the provisions are called). There\'s always solutions to problems.

But rails bear enormous loads and trains are very efficient.

Actually, they use more fuel per passenger than a car.

Which is a kind of waste of resources? But, the man-hours of time
available to passengers because they don\'t have to steer, brake, etc. is
a major savings. Goods and materials traveling via train are effectively
reducing road wear, congestion, and travel time a LOT just by spreading
goods from their point-of-production.

An old diary entry told of a couple who wanted to enjoy some cream, who
had the servants take them by carriage to a dairy... ice cream is
available at all our little groceries because we do NOT need to buy
local.

You guys have gone off the rails. Not worth following this discussion any
more.



--
MRM

 

[Commander Kinsey]

On Tue, 22 Nov 2022 23:35:50 -0000, John Larkin <jlarkin@highlandsnipmetechnology.com> wrote:

On Tue, 22 Nov 2022 22:08:29 -0000, \"Commander Kinsey\"
CK1@nospam.com> wrote:

On Tue, 22 Nov 2022 21:06:22 -0000, John Larkin <jlarkin@highlandsnipmetechnology.com> wrote:

On Tue, 22 Nov 2022 19:20:16 -0000, \"Commander Kinsey\"
CK1@nospam.com> wrote:

On Tue, 22 Nov 2022 15:38:21 -0000, Clive Page <usenet@page2.eu> wrote:

On 18/11/2022 12:04, Martin Brown wrote:

I think they probably could increase the low frequency bound for domestic and modest sized solar or wind farms not to drop off grid. It is preferable to stress a few motors and transformers for a few minutes when compared to the major cost of dropping large segments of load.

Otherwise you get the cascade failure mode that afflicted the UK after a freak lightning strike took out a fairly small electric plant and caused a cascade of failures that took down mains for London and much of England.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836626/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf

It didn\'t help that electric trains required an engineering reset before they could be moved from where they ground to a halt when the mains went down.

It turned out **that** the design spec of the trains was **that** they should cope with a frequency drop to as low as 49 Hz

Why do people put \"that\" everywhere? Retry your sentence without \"that\" in the two instances marked. No change in meaning whatsoever.

but they were built by German engineers who assumed that in a modern country like Germany, but not as it turned out the UK, the mains frequency could *never* drop below 49.5 Hz, so they built in (or failed to avoid) a serious failure mode when this actually occurred. Hence all their class 700 trains stopped.

Surely a failure mode is one where the motor would have been damaged? Why make it fail before it has to?

Messrs Thameslink, the train operator, compounded the problem by only installing in some of their trains a software update which would have allowed the driver to restart the train after it had stopped from this cause.

Why on earth would anyone not give the driver such an ability? Imagine if you had to call someone out because you stalled your car.

Since only a few trains could be restarted, the lines were still pretty well blocked, and the network was effectively at a standstill for about half a day. A combined German and British cock-up you might think.

The whole idea of running things on rails is preposterous. You can\'t go round a broken down vehicle, and you can\'t stop in a sensible time if a lorry has broken down crossing the track.

But rails bear enormous loads and trains are very efficient.

Actually, they use more fuel per passenger than a car.

In the USA, people travel long distances (and we sure have long
distances) by air. The speed ratio is around 10:1.

Trains mostly move freight and products. The fuel cost of a train is
around 1/3 to 1/4 the cost of using trucks.

Not for passengers it isn\'t.

There is a big savings on
labor too. A single freight train can replace several hundred trucks.

The U.S. freight rail network is about 140,000 miles.

Trains are far safer for hazmat transport compared to trucks. 10:1 is
quoted.

 

[Commander Kinsey]

On Tue, 22 Nov 2022 23:39:35 -0000, Carlos E.R. <robin_listas@es.invalid> wrote:

On 2022-11-22 23:08, Commander Kinsey wrote:
On Tue, 22 Nov 2022 21:06:22 -0000, John Larkin
jlarkin@highlandsnipmetechnology.com> wrote:

On Tue, 22 Nov 2022 19:20:16 -0000, \"Commander Kinsey\"
CK1@nospam.com> wrote:

On Tue, 22 Nov 2022 15:38:21 -0000, Clive Page <usenet@page2.eu> wrote:

On 18/11/2022 12:04, Martin Brown wrote:

I think they probably could increase the low frequency bound for
domestic and modest sized solar or wind farms not to drop off grid.
It is preferable to stress a few motors and transformers for a few
minutes when compared to the major cost of dropping large segments
of load.

Otherwise you get the cascade failure mode that afflicted the UK
after a freak lightning strike took out a fairly small electric
plant and caused a cascade of failures that took down mains for
London and much of England.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836626/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf

It didn\'t help that electric trains required an engineering reset
before they could be moved from where they ground to a halt when
the mains went down.

It turned out **that** the design spec of the trains was **that**
they should cope with a frequency drop to as low as 49 Hz

Why do people put \"that\" everywhere? Retry your sentence without
\"that\" in the two instances marked. No change in meaning whatsoever.

but they were built by German engineers who assumed that in a modern
country like Germany, but not as it turned out the UK, the mains
frequency could *never* drop below 49.5 Hz, so they built in (or
failed to avoid) a serious failure mode when this actually
occurred. Hence all their class 700 trains stopped.

Surely a failure mode is one where the motor would have been
damaged? Why make it fail before it has to?

Messrs Thameslink, the train operator, compounded the problem by
only installing in some of their trains a software update which
would have allowed the driver to restart the train after it had
stopped from this cause.

Why on earth would anyone not give the driver such an ability?
Imagine if you had to call someone out because you stalled your car.

Since only a few trains could be restarted, the lines were still
pretty well blocked, and the network was effectively at a standstill
for about half a day. A combined German and British cock-up you
might think.

The whole idea of running things on rails is preposterous. You can\'t
go round a broken down vehicle, and you can\'t stop in a sensible time
if a lorry has broken down crossing the track.

But rails bear enormous loads and trains are very efficient.

Actually, they use more fuel per passenger than a car.

Not true.

It is true, a study was conducted in the UK. The weight of a train is ridiculous.

Now add in the train is never going exactly to and from where each person wants to be, and cars are way better.

Public transport is for poor people.

 

[Peeler]

On Tue, 22 Nov 2022 15:35:50 -0800, John Larkin, another mentally deficient,
troll-feeding, senile ASSHOLE, blathered:

In the USA, people travel long distances (and we sure have long
distances) by air. The speed ratio is around 10:1.

In the USA there are also too many of you useless miserable senile
cocksuckers that are so miserable actually that they are thankful when some
retarded troll will keep engaging them! <BG>

 

[Peeler]

On Wed, 23 Nov 2022 00:39:35 +0100, cretinous Carlos E.R., another brain
dead troll-feeding senile ASSHOLE, blathered

Actually, they use more fuel per passenger than a car.

Not true.

It IS true that HE is a miserable troll and YOU a miserable troll-feeding
senile cretin, you abysmally stupid spick!

 

[The Natural Philosopher]

On 22/11/2022 19:52, SteveW wrote:

On 19/11/2022 07:20, Commander Kinsey wrote:
On Thu, 17 Nov 2022 23:02:30 -0000, SteveW <steve@walker-family.me.uk
wrote:

On 17/11/2022 19:22, Scott Lurndal wrote:
SteveW <steve@walker-family.me.uk> writes:
On 17/11/2022 19:03, Commander Kinsey wrote:

Yes, the European mainland grid whilst it is not all of Europe, is
synchronised.
I believe Norway, the UK and Ireland, are definietly totally
separate.

I thought there was a problem with capacitance sending AC a long
distance, hence DC to the UK?  Yet they\'re managing AC throughout
most
of Europe?

They\'re not having to send it undersea though.

https://en.wikipedia.org/wiki/HVDC_Gotland

Except of course that that is DC link - because it is underwater.

Underwater is irrelevant, it\'s the capacitance in the wire.

It is not irrelevant at all. Overhead, high-voltage wires are
uninsulated. Underwater ones cannot be and also have to have physical
(metal) protection. That alone turns them into very long capacitors.

Yes. When I visited as a teenager the very first UK-FR undersea link,
the engineers said \'if we switch it off and disconnect it, we can draw
an arc for half an hour from the stored electricity\'.

Seawater is a good conductor, unlike air, so the cables must be
insulated, and that insulation forms the bulk of the dielectric.

That\'s why they had to be DC - charging and discharging that capacitance
via a resistive cable cant be done 50 times a second without massive losses.

--
Those who want slavery should have the grace to name it by its proper
name. They must face the full meaning of that which they are advocating
or condoning; the full, exact, specific meaning of collectivism, of its
logical implications, of the principles upon which it is based, and of
the ultimate consequences to which these principles will lead. They must
face it, then decide whether this is what they want or not.

Ayn Rand.

 

[The Natural Philosopher]

On 22/11/2022 23:39, Carlos E.R. wrote:

On 2022-11-22 23:08, Commander Kinsey wrote:
On Tue, 22 Nov 2022 21:06:22 -0000, John Larkin
jlarkin@highlandsnipmetechnology.com> wrote:

On Tue, 22 Nov 2022 19:20:16 -0000, \"Commander Kinsey\"
CK1@nospam.com> wrote:

On Tue, 22 Nov 2022 15:38:21 -0000, Clive Page <usenet@page2.eu> wrote:

On 18/11/2022 12:04, Martin Brown wrote:

I think they probably could increase the low frequency bound for
domestic and modest sized solar or wind farms not to drop off
grid. It is preferable to stress a few motors and transformers for
a few minutes when compared to the major cost of dropping large
segments of load.

Otherwise you get the cascade failure mode that afflicted the UK
after a freak lightning strike took out a fairly small electric
plant and caused a cascade of failures that took down mains for
London and much of England.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836626/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf

It didn\'t help that electric trains required an engineering reset
before they could be moved from where they ground to a halt when
the mains went down.

It turned out **that** the design spec of the trains was **that**
they should cope with a frequency drop to as low as 49 Hz

Why do people put \"that\" everywhere?  Retry your sentence without
\"that\" in the two instances marked. No change in meaning whatsoever.

but they were built by German engineers who assumed that in a
modern country like Germany, but not as it turned out the UK, the
mains frequency could *never* drop below 49.5 Hz, so they built in
(or failed to avoid) a serious failure mode when this actually
occurred.  Hence all their class 700 trains stopped.

Surely a failure mode is one where the motor would have been
damaged?  Why make it fail before it has to?

Messrs Thameslink, the train operator, compounded the problem by
only installing in some of their trains a software update which
would have allowed the driver to restart the train after it had
stopped from this cause.

Why on earth would anyone not give the driver such an ability?
Imagine if you had to call someone out because you stalled your car.

Since only a few trains could be restarted, the lines were still
pretty well blocked, and the network was effectively at a
standstill for about half a day.  A combined German and British
cock-up you might think.

The whole idea of running things on rails is preposterous.  You
can\'t go round a broken down vehicle, and you can\'t stop in a
sensible time if a lorry has broken down crossing the track.

But rails bear enormous loads and trains are very efficient.

Actually, they use more fuel per passenger than a car.

Not true.

Rather depends on how full they are. Commuter trains are very good.
Social routes with one passenger every fortnight, not so much


--
Any fool can believe in principles - and most of them do!

 

[Martin Brown]

On 22/11/2022 16:32, John Larkin wrote:

On Tue, 22 Nov 2022 15:38:21 +0000, Clive Page <usenet@page2.eu
wrote:

On 18/11/2022 12:04, Martin Brown wrote:

I think they probably could increase the low frequency bound for domestic and modest sized solar or wind farms not to drop off grid. It is preferable to stress a few motors and transformers for a few minutes when compared to the major cost of dropping large segments of load.

Otherwise you get the cascade failure mode that afflicted the UK after a freak lightning strike took out a fairly small electric plant and caused a cascade of failures that took down mains for London and much of England.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836626/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf

It didn\'t help that electric trains required an engineering reset before they could be moved from where they ground to a halt when the mains went down.

It turned out that the design spec of the trains was that they should cope with a frequency drop to as low as 49 Hz, but they were built by German engineers who assumed that in a modern country like Germany, but not as it turned out the UK, the mains frequency could *never* drop below 49.5 Hz, so they built in (or failed to avoid) a serious failure mode when this actually occurred. Hence all their class 700 trains stopped.

Messrs Thameslink, the train operator, compounded the problem by only installing in some of their trains a software update which would have allowed the driver to restart the train after it had stopped from this cause. Since only a few trains could be restarted, the lines were still pretty well blocked, and the network was effectively at a standstill for about half a day. A combined German and British cock-up you might think.

I can\'t imagine anything that would cause a reasonable train
propulsion system to fail at 49 Hz, or even 45 Hz.

The fact that the UK mains distribution grid will drop them off load at
48Hz has a lot to do with it. They represent a large \"pure\" load (and so
are a target once the usual intermittent supply folk have been dropped).

Automated load shedding triggers at <48.000Hz.

Snag was that with the modern configuration of local solar panels and
wind shedding 1GW of domestic load also shed 600MW of local generation
so only made a 400MW net contribution. Rinse and repeat leading to a
cascade failure of a much larger section of grid than was strictly
necessary. It will almost certainly fail the same way next time.

Maybe the trains will have a boot from cold function added to their
firmware in future but I\'m not holding my breath.

--
Regards,
Martin Brown

 

[Commander Kinsey]

On Wed, 23 Nov 2022 10:00:06 -0000, The Natural Philosopher <tnp@invalid.invalid> wrote:

On 22/11/2022 19:52, SteveW wrote:
On 19/11/2022 07:20, Commander Kinsey wrote:
On Thu, 17 Nov 2022 23:02:30 -0000, SteveW <steve@walker-family.me.uk
wrote:

On 17/11/2022 19:22, Scott Lurndal wrote:
SteveW <steve@walker-family.me.uk> writes:
On 17/11/2022 19:03, Commander Kinsey wrote:

Yes, the European mainland grid whilst it is not all of Europe, is
synchronised.
I believe Norway, the UK and Ireland, are definietly totally
separate.

I thought there was a problem with capacitance sending AC a long
distance, hence DC to the UK? Yet they\'re managing AC throughout
most
of Europe?

They\'re not having to send it undersea though.

https://en.wikipedia.org/wiki/HVDC_Gotland

Except of course that that is DC link - because it is underwater.

Underwater is irrelevant, it\'s the capacitance in the wire.

It is not irrelevant at all. Overhead, high-voltage wires are
uninsulated. Underwater ones cannot be and also have to have physical
(metal) protection. That alone turns them into very long capacitors.

Yes. When I visited as a teenager the very first UK-FR undersea link,
the engineers said \'if we switch it off and disconnect it, we can draw
an arc for half an hour from the stored electricity\'.

Seawater is a good conductor, unlike air, so the cables must be
insulated, and that insulation forms the bulk of the dielectric.

That\'s why they had to be DC - charging and discharging that capacitance
via a resistive cable cant be done 50 times a second without massive losses.

Are all insulators dielectrics?