From: arl_123234@hotmail.com   
      
   On 4/30/19 2:37 AM, Michael Moroney wrote:   
      
   > 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..   
   >   
      
   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,   
   --   
   J. B. Wood	            e-mail: arl_123234@hotmail.com   
      
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