Literature or definition of signed PF required
Literature or definition of signed PF required
(OP)
Hi
I have had some difficulty in locating information on signed power factor calculations. There seems to be some discrepancy in it's application by different manufacturers of protective relays and injection test sets. Could any-one give me some information as to the standard used for "signed power factor" calculations? I would appreciate it if you could add to your reply if this is an European/North American etc. standard.
I would appreciate any pointers to relevant technical papers, research or other literature. Preferably web based or electronic.
Thank you for your kind attention
Regards
Vlam
I have had some difficulty in locating information on signed power factor calculations. There seems to be some discrepancy in it's application by different manufacturers of protective relays and injection test sets. Could any-one give me some information as to the standard used for "signed power factor" calculations? I would appreciate it if you could add to your reply if this is an European/North American etc. standard.
I would appreciate any pointers to relevant technical papers, research or other literature. Preferably web based or electronic.
Thank you for your kind attention
Regards
Vlam






RE: Literature or definition of signed PF required
Michael Sidiropoulos
RE: Literature or definition of signed PF required
There is a diagram relating real- and reactive-power flow in Handbook for Electricity Metering — Tenth Edition, published by Edison Electric Institute… eei.org
RE: Literature or definition of signed PF required
Displacement power factor is the cosine of the current angle with respect to the voltage. Cosine is positive for both positive and negative angles. If the angle is negative, the power factor is "lagging"; if the angle is positive, the power factor is "leading".
Power factor including effects of harmonics is real power (kW) divided by apparent power (kVA). This is always a positive quantity.
RE: Literature or definition of signed PF required
As there seems to be some confusion on this isue.
See:
1) PM296/RPM096 Power Quality Analyzers @
www.i-jtech.co.kr/manual/PM296_RPM096.pdf page 27; 28
Also used by other North American Relay manufacturers e.g.
GE-Industrial systems :relay manufacturer in the UR series and their Quick Panel series to convey PF via Modbus & DNP to other systems.
This caters for the full four quadrants available to calculate PF with additional information contained in the sign to convey leading/lagging PF info.
See also various other mentioning eg.
Northwood Data Loggers Product Information: Power KeyCard [New Window] [Full Window] [Preview]
The InterLogger Power KeyCard turns the InterLogger into a full function power and harmonics analyzer. ... Average Value for Effective Power, Reactive Power, Apparent Power, and Signed Power Factor for up to 3 Channels. ...
URL: www.rccgroup.com/pkey.html
This Company operates in the US and Canada
etc.
This brings me back to the question on what the definition is, and whose deffinition is it?
Thank you for your interest
Vlam