Anyone knows a good industrial brand for Sag Protection, using energy storage devices such as capacitors, flywheel, or battery for > 1000KVA applications?
This used to be a company called Soft Switch Technologies (SST) who basically invented the entire concept, they were bought by Rockwell a few years ago and rolled into the Allen Bradley fold.
Thanks jraef. We actually have a number of those on site...they work really good. Only thing, they protect against 0% sags for a maximum of 12 cycles. I wanted to see if anyone has any experience with other technologies like flywheel. They claim 14 sec protection, but not sure about maintaining a constantly rotating machine.
EuroDiesel and Piller are the big players in the European rotary UPS market for megawatt-level applications. Are you just after sag / swell protection, or looking for full system protection?
Thanks guys I just checked out the GE site. Also, checked out Piller...just learned they bought Active Power...which I'm familiar with. ScottyUK, this is only for Sag Protection.
Disclaimer: I don't work for them and have no knowledge of how good their stuff is; all I know for sure is they have installed and commissioned a pilot project / feasibility demonstration plant on one of my utility's 28 kV feeders. Near as I can tell their product is intended to supply / absorb both real and reactive power in the short term. Exercise your due diligence...
Incidentally, the subject line of the OP used terminology unfamiliar to me . . . and I immediately wondered how one would protect against conductor sag due to thermal overload; it was only as I read on that I realized - if I've grasped it correctly - that the concern was voltage sag protection...
Second incidentally: My utility has a conductor sag detection facility used to derive realistic continuous and limited time ratings for specific 230 kV circuits that are often very heavily loaded, especially during the summer months [these circuits collectively comprise a "flowgate"]. Ultrasonic proximity detectors are used in conjunction with known line loadings and local ambient temperatures to calculate very accurate effective wind speeds which can then be plugged into the thermal monitoring program to enable said lines to be loaded to their maxima without crossing the fateful line into overload and premature conductor aging.
On Google, look up Solid state voltage regulator. especially look up ABB PCS100 AVC, a solid state voltage regulator available to over 3 MVA. One of my customers uses it on the tertiary of an auto-transformer that has a reactor as well as station servce. When the reactor switches in and out, there is an instantaneous 10% drop in voltage. The station service is on the regulator, and does see a blip.
