What 60 HZ Feels Like - Even Some On-Topic Stuff

As an aside, I toured the Veolia Steam Plant in Philadelphia, yesterday. This plant has been in continuous operation since it opened in 1909, and is quite a remarkable place. I got to be up-close-and-personal with the equipment, including the steam and gas turbines, the boilers, pumps, controls, switchgear, powerhouse and uplink.

Standing under the main step-up transformer (2,300 VAC to 23,000 VAC) is a truly visceral experience. Once one feels that level of "HUM", one will never mistake 60 for 120 ever again.

Relevance:

60 HZ hum suggests a bad or failing rectifier.
120 HZ hum suggests bad or failing filter caps.
50 & 100 for our Euro and Asian friends.

Amazing amount of mechanical-feedback devices in use in these plants - it seems that VFDs and great many "modern" grid-tie devices are simply not sufficiently rugged or reliable at this scale.

Peter Wieck
Melrose Park, PA

On 03/29/19 11:32, Peter Wieck wrote:
> Amazing amount of mechanical-feedback devices in use in these plants - it seems that VFDs and great many "modern" grid-tie devices are simply not sufficiently rugged or reliable at this scale.

mechanical load/speed regulators are very reliable, mechanically simple,
and do a really good job. why "improve" something that works so well?

They typically adjust the frequency setpoint on all of the generators,
which would be overseen by the ISO, and then allow the load/freq slope
to balance load between them all. i would expect that certain kinds of
generators would have a more aggressive slope than others. Nuke plants
need to keep a constant power output, but others (like hydroelectric)
can bounce all over the place as needed to manage grid power levels.

I expect that wind/solar will also try to run at 100% all of the time as
well, to keep costs down.