Novatech Bitronics PowerPlex II, Руководство пользователя

Страница: 96 / 136

96
ML0047 December 1, 2017 Copyright 2017 Bitronics, LLC
Fundamental Volts for that phase (which is the denominator), and the result will be the
actual RMS magnitude of the selected harmonic.
Fundamental Volts and Amps can be used in conjunction to obtain Fundamental VAs,
and when used with Displacement Power Factor can yield Fundamental Watts and
Fundamental VARs.
5.11.5 K-Factor
K-Factor is a measure of the heating effects on
transformers, and it is defined in ANSI/IEEE C57.110-
1986. Equation 4 is used by the PPX II to determine K-
Factor, where "h" is the harmonic number and "I
h
" is the
magnitude of the h
th
harmonic. K-Factor is measured on
each of the three phases of amps, however there is no
"Total" K-Factor. K-Factor, like THD and PF, does not
indicate the actual load on a device, since all three of
these measurements are ratios. Given the same harmonic ratio, the calculated K-
Factor for a lightly loaded transformer will be the same as the calculated K-Factor for a
heavily loaded transformer, although the actual heating on the transformer will be
significantly different.
5.11.6 Displacement Power Factor
Displacement Power Factor is defined as the cosine of the angle (phi) between the
Fundamental Voltage Vector and the Fundamental Current Vector. The sign
convention for Displacement Power Factor is the same as for Power Factor, shown in
Figure 12.
The Total Displacement Power Factor measurement is calculated using the "Power
Triangle", or the three-phase Fundamental WATTS divided by the three-phase
Fundamental VAs. The per-phase Fundamental VA measurement is calculated from
the product of the per-phase Fundamental Amp and Fundamental Volts values. The
three-phase Fundamental VA measurement is the sum of the per-phase Fundamental
VA values (Arithmetic VAs).
5.11.7 Phase Angles
The PPX II measures the Fundamental Phase Angles for all Currents, Line-to-Neutral
Voltages, and Line-to-Line Voltages. The Phase Angles are in degrees, and all are
referenced to the V
A-N
Voltage, which places all Phase Angles in a common reference
system. Values are from -180 to +180 Degrees.
63
2 2
1
63
2
1
h
h
h
h
I h
K Factor
I



 


Equation
4
- K-Factor