Fluke 1760 - Power Factor; Displacement Power Factor Cos Φ

1760
Users Manual
3-16
22
htotd
QQQ −=
The 3-phase distortion reactive power sum is calculated as
321 LdLdLdsumd
QQQQ ++=
Please note that the quadratic terms in the
d
Q calculation means that
22
sumhsumtotsumd
QQQ −≠
Power factor
For the power factor one of two different formulas can be selected by the user through the
“Options > Power Factor” menu in PQ Analyze.
Formula 1: The sign is taken from the reactive harmonic power therefore giving an
indication about inductive or capacitive characteristic of the load.
h
h
Q
Q
S
P
PF ⋅=
Formula 2: The sign is taken from the real power therefore giving the power flow
direction (motor / generator characteristic of the load).
S
P
PF =
The 3-phase power factor sum is calculated as
sumh
sumh
sum
sum
sum
Q
Q
S
P
PF ⋅=
or
sum
sum
sum
S
P
PF =
Displacement power factor cos φ
The cos φ is most commonly referred to as the power factor of the fundamental
component. More general there is a cos φ for every harmonic frequency component.
When you select the harmonics analysis in the main analysis window in PQ Analyze you
can display the cos φ for all harmonics including the fundamental.
Harmonics analysis parameter group:
The formula used for calculating the cos φ is:
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
=
i
i
i
P
Q
arctancoscos ϕ