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Transmission Line Capacitance Affecting Power-factor


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#1 ProcessE

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Posted 04 May 2009 - 07:40 PM

Hi

I don't have much background in power transmission and distribution so forgive me if I say anything stupid smile.gif

Our company has several properties spread over several miles, with our own high voltage transmission line supplying each site. The bulk of our power consumption is at the end of this transmission line where I read about 10MW at a 0.85 PF, (Yes I know this is pretty terrible). The weird thing is that the utility meter at the entrance on the transmission line onto our property is showing a 0.95 PF. There is no other powerfactor modifying equipment of any size on any of the other sites (such as capacitor banks, over excited synchronous motors etc) so I was wondering if it could be the transmission line itself.

My Question is this to be expected? is it normal/possible to pick up a lot of corrective VARs from the capacitance of a transmission line?
Or is it a case that there is something wrong with one or more of the meters? (Most of the information is being pulled from digital relay controllers).

Thanks

#2 ProcessE

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Posted 04 May 2009 - 10:11 PM

Actually don't worry about it, I was given the wrong information, garbage in = garbage out smile.gif

#3 knj

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Posted 16 June 2010 - 12:29 PM

I have a similar problem. I corrected the power factor in a small machine shop 1 1/2 years ago. Took them up to 85-95% by individual motor correction. The problem is suddenly the pf dropped to 68%. I shut down all inductive loads and it didn't change. There are 2 cap. banks on the transmission lines within 3 blocks and a machine shop in the neighborhood closed recently. Their pf reading at the meter is.16....16%...with no load. I think the cap banks are too large now and throwing the current into lead instead of lag and the meters can't read negative. Anyone want to weigh in on this question?




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