Re: [time-nuts] A Research Proposal

[jimlux]

On 7/8/19 8:33 PM, Hal Murray wrote:


jim...@earthlink.net said:

Free space propgation delay for 5500 m is 18.5 milliseconds - compared  to
16.67 millisecond period of 60Hz.  A velocity factor of about 90%


Neat.  Thanks.

What's going on?  I'm used to calculating the velocity from the dielectric
constant.  Power lines have no obvious non-air dielectric.  Is the
dielectric-constant only calculation ignoring some things that are significant
in a power line?  If so, what?




Dielectric affects the C per unit length, which affects the propagation 
constant.


The telegrapher's equation (now the "transmission line equation") was 
developed back in the days of open wire lines with essentially no 
dielectric.



It gets really interesting when looking at three phase power lines, 
because you have to calculate not only the C relative to ground, but the 
C between the wires.  And the L for the wire by itself, and the mutual L 
between wires.


Fortunately, it is a linear system and superposition holds (until 
there's a fault)


This is the big challenge with stabilizing large grids - you have these 
long transmission lines with "springy" generators and loads.  Transients 
can take a long time to die out, as they bounce back and forth along a 
1000km long line, with lots of impedance discontinuities.  So you wind 
up with synchronous condensers and switched reactive components along 
the line.




The real value of DC links is that they're MUCH easier to stabilize.


Measuring the phase along such a line could be really interesting, 
especially if you had a source of switching events information.  The 
power companies have all this, and direct connections to do the 
measurements.


The intriguing thing is to do it "non-contact" and see what you can 
figure out.  I suspect, also, that the local power distribution company 
probably doesn't care much about it - to them, it's all loads, and what 
they watch is overall power factor - in a residential area, I'd bet the 
PF is very close to 1 (resistive loads). In industrial areas, there are 
lots of motors and magnetic ballasts for lighting, so you get a lagging 
PF, but I'll bet with all the variable speed drives and electronic 
ballasts, not to say LED lighting, things are changing.





___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Bill Hawkins]

Um, you're quite right that DC lines have no phase angle - unless you call a 
polarity reversal a 180 degree shift.

I was referring to the phase angle of the AC side of an inverter with respect 
to the average phase angle of the grid that it is connected to. 
It behaves just like a synchronous machine.  Advance the phase angle of the 
inverter and it pumps energy into the grid. 
The inverter at the other end of the DC line must be lagging in order to take 
power from that grid.
Conservation of energy says you must take more power than you deliver in order 
to cover the resistive and corona losses in the DC line and the conversion 
losses in the inverters.

Perhaps the source inverter phase angle is controlled by the DC output voltage, 
and the load phase angle is controlled by the DC current.  Controlling the load 
inverter phase angle would be like adjusting the steam to a turbine coupled to 
a generator.  I have no knowledge of how control is actually accomplished.

Bill Hawkins

On Mon, Jul 8, 2019, at 6:12 AM, Hal Murray wrote:
> 
> bill.i...@pobox.com said:
> > Since the direction of power flow depends on the phase angle between the
> > synchronous source and load, it seems to me that the difference between the
> > average phase angle in one region and that in another (at the ends of a DC
> > transmission line) will tell you which way power is flowing.
> 
> Nope.  The phase angle difference tells you a lot on an AC line, but nothing 
> on a DC line.  For DC, the frequencies can even be different.  That means the 
> phase angle is changing, and it can wrap around while the phase angle on an 
> AC 
> system is always small.
> 
> A classic 3 phase synchronous motor is also a generator if you are pushing it 
> rather than it is pushing you.  The sign of the phase angle flips between 
> motor and generator.  In this context, the phase angle is the angle the 
> magnetic lines make between the rotor and stator.
> 
> 
> -- 
> These are my opinions.  I hate spam.
> 
> 
> 
> 
> ___
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to 
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>

___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[jimlux]

On 7/8/19 7:05 PM, Dana Whitlow wrote:

I'm surprised that the VF of HV transmission lines is noticeably less than
unity, given
that the dielectric is just air.  Or does the distributed resistance do all
the damage?




It's all about L and C  that creates the delay - propagation constant is 
proportional to 1/sqrt(L*C), Z is sqrt(L/C)


So you see those funky delay line coaxes with Z=1000 ohms - a spiral 
center conductor(with a magnetic core) jacks up the L.



Check out the link to the lecture notes I had...

___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Dana Whitlow]

I'm surprised that the VF of HV transmission lines is noticeably less than
unity, given
that the dielectric is just air.  Or does the distributed resistance do all
the damage?

Dana


On Mon, Jul 8, 2019 at 8:00 PM jimlux  wrote:

> On 7/8/19 3:11 PM, Hal Murray wrote:
> >
> > glenl...@pacificmedia.com.au said:
> >> I think  people getting confused with the phase of measured current to
> the
> >> voltage .
> >
> > No, we have been discussion the phase angle between 2 geographically
> separated
> > locations connected by a power line.
> >
> > Consider the simple case of a generator, 100 miles of line, and then a
> light
> > bulb.  The voltage at the light bulb will be delayed by the speed of
> light.
> > That delay can be expressed as a fraction of a cycle and converted to a
> phase
> > angle.
>
> >
> > It gets much more complicated if you have multiple generators, multiple
> loads,
> > and various transmission lines, and even more complicated when you turn
> things
> > on and off.
>
>
> The transmission line is decidedly not Velocity Factor =1.0
>
> A typical propagation constant might be j0.0018/mile
>
> about 5500 km/wavelength at 60 Hz.
>
> Free space propgation delay for 5500 m is 18.5 milliseconds - compared
> to 16.67 millisecond period of 60Hz.  A velocity factor of about 90%
>
> (that's for an example I found for 765 kV, using Tern conductors, in
> bundles of 6
>
> http://home.engineering.iastate.edu/~jdm/ee552/Transmission.pdf
> )
>
>
> >
> >
>
>
> ___
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[jimlux]

On 7/8/19 3:11 PM, Hal Murray wrote:


glenl...@pacificmedia.com.au said:

I think  people getting confused with the phase of measured current to  the
voltage .


No, we have been discussion the phase angle between 2 geographically separated
locations connected by a power line.

Consider the simple case of a generator, 100 miles of line, and then a light
bulb.  The voltage at the light bulb will be delayed by the speed of light.
That delay can be expressed as a fraction of a cycle and converted to a phase
angle.




It gets much more complicated if you have multiple generators, multiple loads,
and various transmission lines, and even more complicated when you turn things
on and off.



The transmission line is decidedly not Velocity Factor =1.0

A typical propagation constant might be j0.0018/mile

about 5500 km/wavelength at 60 Hz.

Free space propgation delay for 5500 m is 18.5 milliseconds - compared 
to 16.67 millisecond period of 60Hz.  A velocity factor of about 90%


(that's for an example I found for 765 kV, using Tern conductors, in 
bundles of 6


http://home.engineering.iastate.edu/~jdm/ee552/Transmission.pdf
)








___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Hal Murray]

glenl...@pacificmedia.com.au said:
> I think  people getting confused with the phase of measured current to  the
> voltage . 

No, we have been discussion the phase angle between 2 geographically separated 
locations connected by a power line.

Consider the simple case of a generator, 100 miles of line, and then a light 
bulb.  The voltage at the light bulb will be delayed by the speed of light.  
That delay can be expressed as a fraction of a cycle and converted to a phase 
angle.

It gets much more complicated if you have multiple generators, multiple loads, 
and various transmission lines, and even more complicated when you turn things 
on and off.


-- 
These are my opinions.  I hate spam.




___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Glen English VK1XX]

with regard to phase angle and confusion over load and power flow ...

I think  people getting confused with the phase of measured current to 
the voltage .


the voltage phase is fixed, and should be consistent . when you measure 
the current phase, relatve to the voltage, that tells you about the flow 
(and PF)


So using a AC-AC filament transformer and a fast opto on the secondary , 
with some care that it doesnt saturate the transistor to slow the 
turnoff,  in a nice thermally controlled environment, seems suitable.


-glen




___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Bill Byrom]

Andy, it appears to me that the FNET/GridEye system already does what you 
propose:
http://fnetpublic.utk.edu

The Angle Contour Map displays the kind of results you desire. But it doesn't 
know the Western Interconnection at this time. I believe there is a typo at the 
top of the Angle Contour Map:
> The frequency gradient map visualizes the real-time angle "differences" with 
> respect to a referential point in Eastern
> Interconnection.
Shouldn't that state: "The ANGLE CONTOUR MAP visualizes ..."?

According to the legend, the angle contour map displays a measure of the phase 
angle differences between the individual FDR hosts and a "referential point". 
I'm not sure if that is an actual specific FDR host or some averaged phase.

Of course, you need to think carefully in a relativistic manner when you are 
trying to look at local phase in locations so far apart. At 60 Hz (in the US) 1 
degree of phase corresponds to 46.3 us. That's the free space propagation delay 
of light over 13.89 km (8.63 miles).  Generators 777 miles apart have a 90 
degree phase relationship with respect to free space propagation phase.
--
Bill Byrom N5BB
Irving, TX

On Mon, Jul 8, 2019, at 6:11 AM, Andy Backus wrote:
> To clarify:
> 
> My research proposal is for data to be taken within the same interconnection.
> 
> It does not care about frequency.
> 
> It does not care about Time Error.
> 
> It only seeks to characterize the phase differences between the power 
> line signal presented in regions of the distribution system separated 
> by significant geographical distances.
> 
> 180-degree phase reversals and three-phase transformations along the 
> chain of information are easily distinguishable.
> 
> Thanks for your interest.  I hope some will accept the technical 
> challenge of gathering data -- which is fairly minimal.
> 
> Andy Backus
> Bellingham, WA
> (Western Interconnection)
> 

> ___
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to 
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>

___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Tom Van Baak]

> I hope some will accept the technical challenge of gathering data -- 
which is fairly minimal.


Andy,

It may have been before you joined time-nuts, but some years ago we 
compared mains phase/frequency between Albuquerque, NM and Seattle, WA, 
which in spite of being some 1500 miles apart are on the same grid. 
Another test was between two nearby locations, Bellevue, WA and Redmond, 
WA. All data was taken by timing zero-crossings to the microsecond with 
a picPET. You'll find the results fascinating:


http://leapsecond.com/pages/mains-cv/

I'm happy to repeat any of this analysis using recent data from Hal 
(CA), and you (Bellingham, WA), and me (Bellevue, WA).


A third test which is interesting is comparing independent mains 
phase/frequency between different rooms of the same house. In general 
you want to understand local house effects, then neighborhood effects, 
then city / country effects before you jump into interstate grid 
effects. It's similar to establishing baselines and noise floors when 
you make precision clock measurements.


/tvb

On 7/7/2019 11:49 PM, Andy Backus wrote:

To clarify:

My research proposal is for data to be taken within the same interconnection.

It does not care about frequency.

It does not care about Time Error.

It only seeks to characterize the phase differences between the power line 
signal presented in regions of the distribution system separated by significant 
geographical distances.

180-degree phase reversals and three-phase transformations along the chain of 
information are easily distinguishable.

Thanks for your interest.  I hope some will accept the technical challenge of 
gathering data -- which is fairly minimal.

Andy Backus
Bellingham, WA
(Western Interconnection)



From: time-nuts  on behalf of Dave 
ZL3FJ<2c...@silverbears.nz>
Sent: Sunday, July 7, 2019 9:23 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] A Research Proposal

I have here a pair of instruments that were part  of a system used  at one time 
 in a power station here in NZ  to control the time error in one  part of the 
national grid. It controlled the selected generators and provided a real time 
display of the time error between a reference standard and the 50 Hz mains 
frequency.  The system comprised an HP 5280A reversible counter  with two 
inputs, one from the  mains 50 Hz as generated and one from the reference 
standard. These two inputs were arranged to add  counts from one input and 
subtract counts from the other, such that the counter displayed zero while the 
generated 50 Hz was accurate. Offsets from 50Hz were displayed as positive or 
negative counts. The reference input was derived from an HP 105A quartz 
oscillator and the system included provision to manually  synch that to the 
national standard time standard on an as required basis. The output of the 
5280A counter drove an HP 6933B D/A converter, the bi-polar DC output of which 
was used (both magnitude and sign)  to control the governors on some of the 
hydro generators. Dual HP 5321B clocks were used to display TOD from both 
sources.
  The 6933B is complete but the 5280A counter has been partly disassembled.  
The 5321Bs never got this far-neither did the 105A- who knows, it might still 
be being used  as a reference!

DaveB, NZ

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@lists.febo.com] On Behalf Of Bill 
Hawkins
Sent: Monday, July 08, 2019 06:48
To: Bob via time-nuts
Subject: Re: [time-nuts] A Research Proposal

Group,

We've discussed this before, but maybe it needs to be said again.

Line frequency is not constant.   There is no master PLL.  Approximate 
frequency is maintained by a central power dispatching office in each of the 
four (?) regions tied together by their power distribution grid.  The 
dispatcher's goal is to create the same number of cycles of AC each day.  IIRC, 
power is bought and sold by the number of cycles generated.   As the daytime 
load increases, the generators slow down a bit.  Note that it is not possible 
for each generating station to control its frequency, as that would not be 
stable.  Instead, the dispatcher asks various plant operators to generate more 
or less steam (or water flow) in order to increase the frequency.  When the 
load drops at night, the generators speed up a bit, and steam has to be 
reduced. At the end of the day, so to speak, the number of cycles generated is 
very nearly equal to the number generated if the line frequency had been steady 
at 60 (or 50) cycles per second.  Synchronous clocks stay accurate although 
they may be off by a few seconds as dispatchers scramble to get enough steam to 
keep up.

So yes, you can get phase data within a region but you must compensate timing 
data as the frequency varies.

The regions are connected to each other for purposes of power sharing with DC 
transmission lines.  These use inverters to convert b

[time-nuts] A Research Proposal

[Mark Sims]

The message that the TrueTime/Symmetricom FTM-III power line monitor card for 
the XL/XLi receivers contains:

A time error (number of accumulated seconds of error based upon the line 
frequency)

The current frequency error from nominal 50/60 Hz

The current measured line frequency (0.001 Hz res).

The time that a line freq driven clock would be showing.
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Andy Backus]

To clarify:

My research proposal is for data to be taken within the same interconnection.

It does not care about frequency.

It does not care about Time Error.

It only seeks to characterize the phase differences between the power line 
signal presented in regions of the distribution system separated by significant 
geographical distances.

180-degree phase reversals and three-phase transformations along the chain of 
information are easily distinguishable.

Thanks for your interest.  I hope some will accept the technical challenge of 
gathering data -- which is fairly minimal.

Andy Backus
Bellingham, WA
(Western Interconnection)



From: time-nuts  on behalf of Dave ZL3FJ 
<2c...@silverbears.nz>
Sent: Sunday, July 7, 2019 9:23 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] A Research Proposal

I have here a pair of instruments that were part  of a system used  at one time 
 in a power station here in NZ  to control the time error in one  part of the 
national grid. It controlled the selected generators and provided a real time 
display of the time error between a reference standard and the 50 Hz mains 
frequency.  The system comprised an HP 5280A reversible counter  with two 
inputs, one from the  mains 50 Hz as generated and one from the reference 
standard. These two inputs were arranged to add  counts from one input and 
subtract counts from the other, such that the counter displayed zero while the 
generated 50 Hz was accurate. Offsets from 50Hz were displayed as positive or 
negative counts. The reference input was derived from an HP 105A quartz 
oscillator and the system included provision to manually  synch that to the 
national standard time standard on an as required basis. The output of the 
5280A counter drove an HP 6933B D/A converter, the bi-polar DC output of which 
was used (both magnitude and sign)  to control the governors on some of the 
hydro generators. Dual HP 5321B clocks were used to display TOD from both 
sources.
 The 6933B is complete but the 5280A counter has been partly disassembled.  The 
5321Bs never got this far-neither did the 105A- who knows, it might still be 
being used  as a reference!

DaveB, NZ

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@lists.febo.com] On Behalf Of Bill 
Hawkins
Sent: Monday, July 08, 2019 06:48
To: Bob via time-nuts
Subject: Re: [time-nuts] A Research Proposal

Group,

We've discussed this before, but maybe it needs to be said again.

Line frequency is not constant.   There is no master PLL.  Approximate 
frequency is maintained by a central power dispatching office in each of the 
four (?) regions tied together by their power distribution grid.  The 
dispatcher's goal is to create the same number of cycles of AC each day.  IIRC, 
power is bought and sold by the number of cycles generated.   As the daytime 
load increases, the generators slow down a bit.  Note that it is not possible 
for each generating station to control its frequency, as that would not be 
stable.  Instead, the dispatcher asks various plant operators to generate more 
or less steam (or water flow) in order to increase the frequency.  When the 
load drops at night, the generators speed up a bit, and steam has to be 
reduced. At the end of the day, so to speak, the number of cycles generated is 
very nearly equal to the number generated if the line frequency had been steady 
at 60 (or 50) cycles per second.  Synchronous clocks stay accurate although 
they may be off by a few seconds as dispatchers scramble to get enough steam to 
keep up.

So yes, you can get phase data within a region but you must compensate timing 
data as the frequency varies.

The regions are connected to each other for purposes of power sharing with DC 
transmission lines.  These use inverters to convert between AC and DC. The AC 
frequency is controlled by the grid that it is tied to.  Phase angle can be 
changed to change the amount and direction of the power transferred.

So no, you can't compare data from different regions, unless you want to know 
which way DC power is flowing.

I hope this was informative.

Bill Hawkins


On Thu, Jul 4, 2019, at 2:00 PM, Andy Backus wrote:
> Historically, and even today, the steady frequency of AC power has
> been used for timekeeping.  So there may be interest here in the
> following research proposal:
>
> Within a given power distribution grid, several observers as widely
> separated geographically as possible, time stamp the first two zero
> crossings of the power line after each UTC second – over the course of
> 24 hours (86,400 pairs of data).
>
> Popularly conceived, all the components of a power distribution grid
> are phase locked – though, of course, power is taken in and out by
> varying degrees of lead or lag.  Frequency is maintained by a constant
> balancing act between load and generation.
>
> Typical powe

Re: [time-nuts] A Research Proposal

[Dave ZL3FJ]

I have here a pair of instruments that were part  of a system used  at one time 
 in a power station here in NZ  to control the time error in one  part of the 
national grid. It controlled the selected generators and provided a real time 
display of the time error between a reference standard and the 50 Hz mains 
frequency.  The system comprised an HP 5280A reversible counter  with two 
inputs, one from the  mains 50 Hz as generated and one from the reference 
standard. These two inputs were arranged to add  counts from one input and 
subtract counts from the other, such that the counter displayed zero while the 
generated 50 Hz was accurate. Offsets from 50Hz were displayed as positive or 
negative counts. The reference input was derived from an HP 105A quartz 
oscillator and the system included provision to manually  synch that to the 
national standard time standard on an as required basis. The output of the 
5280A counter drove an HP 6933B D/A converter, the bi-polar DC output of which 
was used (both magnitude and sign)  to control the governors on some of the 
hydro generators. Dual HP 5321B clocks were used to display TOD from both 
sources.
 The 6933B is complete but the 5280A counter has been partly disassembled.  The 
5321Bs never got this far-neither did the 105A- who knows, it might still be 
being used  as a reference!

DaveB, NZ

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@lists.febo.com] On Behalf Of Bill 
Hawkins
Sent: Monday, July 08, 2019 06:48
To: Bob via time-nuts
Subject: Re: [time-nuts] A Research Proposal

Group,

We've discussed this before, but maybe it needs to be said again.

Line frequency is not constant.   There is no master PLL.  Approximate 
frequency is maintained by a central power dispatching office in each of the 
four (?) regions tied together by their power distribution grid.  The 
dispatcher's goal is to create the same number of cycles of AC each day.  IIRC, 
power is bought and sold by the number of cycles generated.   As the daytime 
load increases, the generators slow down a bit.  Note that it is not possible 
for each generating station to control its frequency, as that would not be 
stable.  Instead, the dispatcher asks various plant operators to generate more 
or less steam (or water flow) in order to increase the frequency.  When the 
load drops at night, the generators speed up a bit, and steam has to be 
reduced. At the end of the day, so to speak, the number of cycles generated is 
very nearly equal to the number generated if the line frequency had been steady 
at 60 (or 50) cycles per second.  Synchronous clocks stay accurate although 
they may be off by a few seconds as dispatchers scramble to get enough steam to 
keep up.

So yes, you can get phase data within a region but you must compensate timing 
data as the frequency varies.

The regions are connected to each other for purposes of power sharing with DC 
transmission lines.  These use inverters to convert between AC and DC. The AC 
frequency is controlled by the grid that it is tied to.  Phase angle can be 
changed to change the amount and direction of the power transferred.

So no, you can't compare data from different regions, unless you want to know 
which way DC power is flowing.

I hope this was informative.

Bill Hawkins


On Thu, Jul 4, 2019, at 2:00 PM, Andy Backus wrote:
> Historically, and even today, the steady frequency of AC power has 
> been used for timekeeping.  So there may be interest here in the 
> following research proposal:
> 
> Within a given power distribution grid, several observers as widely 
> separated geographically as possible, time stamp the first two zero 
> crossings of the power line after each UTC second – over the course of
> 24 hours (86,400 pairs of data).
> 
> Popularly conceived, all the components of a power distribution grid 
> are phase locked – though, of course, power is taken in and out by 
> varying degrees of lead or lag.  Frequency is maintained by a constant 
> balancing act between load and generation.
> 
> Typical power distribution grids, however, are sized on a scale of 
> thousands of miles.  “Locking phase,” then, is problematic simply on 
> the basis of the limits of information transmission rate.  Even at c, 
> every 1000 miles takes 5 ms, which represents a third to a quarter of 
> the period of the AC power waveform.
> 
> Many interesting phenomena might result from that reality, which 
> suggests a certain constrained flexibility over large distances – 
> almost as if the system is like a large lake of viscous liquid.  When 
> there are local disturbances such as rapid load changes or sudden 
> generation adjustments, for example, it is quite possible harmonic 
> ripples could be propagated through the system.
> 
> Such effects could be observed by comparing phase data across 
> significant distances within a distribution gri

Re: [time-nuts] A Research Proposal

[Bill Hawkins]

Since the direction of power flow depends on the phase angle between the 
synchronous source and load, it seems to me that the difference between the 
average phase angle in one region and that in another (at the ends of a DC 
transmission line) will tell you which way power is flowing.  I didn't claim 
that the amount of power could be determined.  It can't.

Disclaimer - I'm a mechanical engineer who has made a career in the control of 
physical machines.  I've been interested in the power line stuff since a visit 
to the PenJerDel region distribution control center in the seventies.  Now that 
I'm 81, there's probably some holes in that knowledge.

Bill Hawkins

P.S.  I don't know who Bob is. That's the address pobox gave me when I said 
"Reply to List"

On Sun, Jul 7, 2019, at 5:00 PM, Hal Murray wrote:
> 
> > So no, you can't compare data from different regions, unless you want to 
> > know
> > which way DC power is flowing. 
> 
> How does knowing data about two regions tell me anything about how much power 
> is flowing and which direction?
> 
> 
> 
> -- 
> These are my opinions.  I hate spam.
> 
> 
> 
> 
> ___
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to 
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>

___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Glen English VK1XX]

In Australia, we have a national grid. It's big.

National meaning all but a few isolated towns like Darwin, Perth. Perth 
might be connected via a 1800 km HVDC line in the future... which is a 
different story  DC interconnectors


So, I gather  someone  with their MASER in Adelaide could compare their 
MASER to the 50 Hz over some period, and provide the relative offset of 
the grid to others, so others  in australia also observing and averaging 
over some period , could get a useful frequency reference from their 
wall socket.


-which I gather is what people do , since i am new to this timing game.

That would have its limits depending on the ADEV of the mains . and the 
use of DC interconnectors.


-glen

On 8/07/2019 11:21 AM, Bob kb8tq wrote:

Hi

The whole “phase here vs phase there” thing was at the heart of the papers the
power guys started presenting back in the late 1980’s …. A




___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Bob kb8tq]

Hi

The whole “phase here vs phase there” thing was at the heart of the papers the 
power guys started presenting back in the late 1980’s …. At least back then the 
data
was between points a lot further spread out than both sides of a valley.

Bob

> On Jul 7, 2019, at 5:39 PM, jimlux  wrote:
> 
> On 7/7/19 11:48 AM, Bill Hawkins wrote:
>> Group,
>> We've discussed this before, but maybe it needs to be said again.
>> Line frequency is not constant.  
> 
> 
> I think the research is more about understanding the frequency and time 
> shifts across the network, referred to a more accurate and stable reference.  
> Not so much trying to use the grid as a time/frequency reference.
> 
> For instance, is the variation in phase across the San Fernando Valley 
> different in the afternoon when everyone turns on their air conditioner - 
> sure there's a "voltage at the user" change, but is there also a phase change.
> 
> 
> 
> ___
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to 
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.


___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[jimlux]

On 7/7/19 11:48 AM, Bill Hawkins wrote:

Group,

We've discussed this before, but maybe it needs to be said again.

Line frequency is not constant.  



I think the research is more about understanding the frequency and time 
shifts across the network, referred to a more accurate and stable 
reference.  Not so much trying to use the grid as a time/frequency 
reference.


For instance, is the variation in phase across the San Fernando Valley 
different in the afternoon when everyone turns on their air conditioner 
- sure there's a "voltage at the user" change, but is there also a phase 
change.




___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Hal Murray]

> So no, you can't compare data from different regions, unless you want to know
> which way DC power is flowing. 

How does knowing data about two regions tell me anything about how much power 
is flowing and which direction?



-- 
These are my opinions.  I hate spam.




___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Re: [time-nuts] A Research Proposal

[Bill Hawkins]

Group,

We've discussed this before, but maybe it needs to be said again.

Line frequency is not constant.   There is no master PLL.  Approximate 
frequency is maintained by a central power dispatching office in each of the 
four (?) regions tied together by their power distribution grid.  The 
dispatcher's goal is to create the same number of cycles of AC each day.  IIRC, 
power is bought and sold by the number of cycles generated.   As the daytime 
load increases, the generators slow down a bit.  Note that it is not possible 
for each generating station to control its frequency, as that would not be 
stable.  Instead, the dispatcher asks various plant operators to generate more 
or less steam (or water flow) in order to increase the frequency.  When the 
load drops at night, the generators speed up a bit, and steam has to be 
reduced. At the end of the day, so to speak, the number of cycles generated is 
very nearly equal to the number generated if the line frequency had been steady 
at 60 (or 50) cycles per second.  Synchronous clocks stay accurate although 
they may be off by a few seconds as dispatchers scramble to get enough steam to 
keep up.

So yes, you can get phase data within a region but you must compensate timing 
data as the frequency varies.

The regions are connected to each other for purposes of power sharing with DC 
transmission lines.  These use inverters to convert between AC and DC. The AC 
frequency is controlled by the grid that it is tied to.  Phase angle can be 
changed to change the amount and direction of the power transferred.

So no, you can't compare data from different regions, unless you want to know 
which way DC power is flowing.

I hope this was informative.

Bill Hawkins


On Thu, Jul 4, 2019, at 2:00 PM, Andy Backus wrote:
> Historically, and even today, the steady frequency of AC power has been 
> used for timekeeping.  So there may be interest here in the following 
> research proposal:
> 
> Within a given power distribution grid, several observers as widely 
> separated geographically as possible, time stamp the first two zero 
> crossings of the power line after each UTC second – over the course of 
> 24 hours (86,400 pairs of data).
> 
> Popularly conceived, all the components of a power distribution grid 
> are phase locked – though, of course, power is taken in and out by 
> varying degrees of lead or lag.  Frequency is maintained by a constant 
> balancing act between load and generation.
> 
> Typical power distribution grids, however, are sized on a scale of 
> thousands of miles.  “Locking phase,” then, is problematic simply on 
> the basis of the limits of information transmission rate.  Even at c, 
> every 1000 miles takes 5 ms, which represents a third to a quarter of 
> the period of the AC power waveform.
> 
> Many interesting phenomena might result from that reality, which 
> suggests a certain constrained flexibility over large distances – 
> almost as if the system is like a large lake of viscous liquid.  When 
> there are local disturbances such as rapid load changes or sudden 
> generation adjustments, for example, it is quite possible harmonic 
> ripples could be propagated through the system.
> 
> Such effects could be observed by comparing phase data across 
> significant distances within a distribution grid.
> 
> Andy Backus
> Bellingham, WA
> USA
> 
> 
> From: time-nuts  on behalf of Thomas 
> D. Erb 
> Sent: Thursday, July 4, 2019 5:23 AM
> To: time-nuts@lists.febo.com
> Subject: Re: [time-nuts] 60 Hz frequency and phase measurement
> 
snip
> I had a recent tour of a power station - the operators had no idea the 
> output was synchronized to a time standard - they just synchronize with 
> the local grid.

> 
> Thomas D. Erb
> p:508-359-4396
> f:508-359-4482
> a:97 West Street, Medfield, MA 02052 USA
> e: t...@electrictime.com
> w:www.electrictime.com
> Tower & Street Clocks Since 1928
> 

___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

[time-nuts] A Research Proposal

[Andy Backus]

Historically, and even today, the steady frequency of AC power has been used 
for timekeeping.  So there may be interest here in the following research 
proposal:

Within a given power distribution grid, several observers as widely separated 
geographically as possible, time stamp the first two zero crossings of the 
power line after each UTC second – over the course of 24 hours (86,400 pairs of 
data).

Popularly conceived, all the components of a power distribution grid are phase 
locked – though, of course, power is taken in and out by varying degrees of 
lead or lag.  Frequency is maintained by a constant balancing act between load 
and generation.

Typical power distribution grids, however, are sized on a scale of thousands of 
miles.  “Locking phase,” then, is problematic simply on the basis of the limits 
of information transmission rate.  Even at c, every 1000 miles takes 5 ms, 
which represents a third to a quarter of the period of the AC power waveform.

Many interesting phenomena might result from that reality, which suggests a 
certain constrained flexibility over large distances – almost as if the system 
is like a large lake of viscous liquid.  When there are local disturbances such 
as rapid load changes or sudden generation adjustments, for example, it is 
quite possible harmonic ripples could be propagated through the system.

Such effects could be observed by comparing phase data across significant 
distances within a distribution grid.

Andy Backus
Bellingham, WA
USA


From: time-nuts  on behalf of Thomas D. Erb 

Sent: Thursday, July 4, 2019 5:23 AM
To: time-nuts@lists.febo.com
Subject: Re: [time-nuts] 60 Hz frequency and phase measurement

We have used line frequency counting for time keeping in the past  it works 
very well in the USA - EXCEPT in locations with lots of dimmers - theaters in 
particular chop the AC waveform creating lots of noise and can make the 
internal timer run fast.  I think at one location we had 5 volts of noise on 
the mains. TXO chips just always work - so we use them now, or GPS.

I had a recent tour of a power station - the operators had no idea the output 
was synchronized to a time standard - they just synchronize with the local grid.

For a history of line frequency time keeping, Wikipedia has a good entry.
https://en.wikipedia.org/wiki/Telechron

Though Tesla I believe demonstrated this at the Chicago World's fair.

I have a master in my small museum.
https://electricclock.omeka.net/items/show/12





Thomas D. Erb
p:508-359-4396
f:508-359-4482
a:97 West Street, Medfield, MA 02052 USA
e: t...@electrictime.com
w:www.electrictime.com
Tower & Street Clocks Since 1928

___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
___
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to 
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.