Another MV Distribution

Hello, all, and I may have posted this question once before, which has to do with procedure rather than a theoretical understanding: On
overhead MV distribution systems one often observes a bank of power factor (PF) correction capacitors. I get the theory but how do engineers decide the location for these capacitors? Is it based upon actual measurement of MV PF at a location or an estimate by electric utility engineers? They've got to come up with the amount of KVAR correction required by some means. I've never seen any PF measurement equipment designed for direct connection to MV lines (seems kind of dangerous). Thanks for your time and comment. Sincerely,
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J. B. Wood e-mail: arl snipped-for-privacy@hotmail.com

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Large industrial users have power meters which measure the power factor (and the electric company will bill them accordingly if low), so I would not be surprised if they have PF measuring meters here and there permanently installed to keep track of things. They can always install the caps near a known large inductive load like a large transformer bank. It will have known characteristics which will tell them how large a cap bank they need. A set of regulator transformers near my work has a capacitor bank two poles upstream. I remember reading something once that they try to install the cap bank near the low PF source, but always "upstream" of it, not beyond it, if it's a tap off a continuing line..
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On 4/30/19 2:37 AM, Michael Moroney wrote:

Thanks for the reply, Michael. Yes, come industrial locations have the "demand" meters to which you refer. Theory says that the PF correction should be as close to the load as possible. My question was how to come up with the location and capacitor KVAR value needed on a MV distribution line intended to service a group of downstream loads. Transformers, while certainly having some inductance (lagging PF) alone probably don't contribute nearly as much as a bunch of running electric motors (primarily industrial not residential). I'm still searching for some IEEE papers on the subject of choosing the location on a MV feeder for group PF correction. The presence of voltage harmonics and resonance conditions I think also have to be factored in. I'm also wondering if the substation has the capability to monitor the aggregate reactive volt-amperes of the downstream MV feeder lines. (For the record I'm a EE by training but have spent my career in the communications and antenna design area, not AC power generation and distribution.) Sincerely,
--
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