[time-nuts] 60hz disciplined watch

[Poul-Henning Kamp]

In message <4DAF0B0D.4080501 at earthlink.net>, Jim Lux writes:

>I found this in a generator interconnection agreement:
>
>This frequency response control shall, when enabled at the direction of 
>CAISO, continuously monitor the system frequency and automatically 
>reduce the real power output of the Asynchronous Generating Facility 
>with a droop equal to a one-hundred (100) percent decrease in plant 
>output for a five (5) percent rise in frequency (five (5) percent droop) 
>above an intentional dead band of 0.036 Hz

Neither that text nor any other I have been able to find, guarantee
that the integral (= long term average) of the frequency will
converge on 60Hz, only that the instantaneous frequency will stay
in an particular range.

>tvb's data at http://leapsecond.com/pages/mains/  [...]

That data confirms what I said:  Maybe if you average over a couple
of months, but the practical problems related to doing that are
enormous.

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