[BLDG-SIM] Motor efficiencies when driven by VFD

["Bill" <bkoran@xxxxxxxxx>]

Title: Motor efficiencies when driven by VFD

I'm looking for data pertaining to the subject.  I found information on motor efficiencies at various loads, such as from the MotorMaster database and a couple of research papers.  However, I haven't found clear information on motor efficiencies when driven by VFDs.  Here are the types of information that could be useful:

Efficiency vs. load at constant speed (have that for non-VFD applications)
Efficiency vs. speed at constant load

I'm also aware that VFDs can be setup different ways, but I don't know much about this.  I suspect that how the volts per Hz varies impacts the motor efficiency, so that type of information would also be valuable.

Or are VFD setups for HVAC applications inconsistent, so it is hard to generalize?

I am seeking this information because I am working on some spreadsheet applications for the CEC (that will be available to everyone) for estimating savings for changes to variable-flow systems (change to pressure setpoints, resets, etc.)

Any relevant information would be helpful.  I may not be able to incorporate all the information now, but I'd like to know (and eventually address!) any shortcomings in my current applications.

Thanks,
Bill

William E. Koran, P.E.
Senior Energy Engineer
P│E│C│I
Portland Energy Conservation Inc.
1400 SW 5th Avenue, Suite 700
Portland, Oregon 97201
Voice: 503-595-4441
Fax: 503-295-0820
Web: www.peci.org

=====================================================You received this e-mail because you are subscribed
to the BLDG-SIM@xxxxxxxx mailing list.  To unsubscribe
from this mailing list send a blank message to
BLDG-SIM-UNSUBSCRIBE@xxxxxxxx