Omicron CP TD1 - Page 35

OMICRON 35
Introduction to capacitance and dissipation factor measurement
Figure 4-7: Example for the temperature behavior of RBP, RIP and OIP bushings
1
The dissipation factor is dependent on the frequency. With modern test devices like the CPC 100 +
CP TD1, it is possible to cover a wide frequency range for capacitance and DF measurements.
Conventional fingerprint measurements for comparison are normally available only at line frequency.
The following figures show the frequency dependency for transformer windings (oil-paper insulation) and
an OIP bushing. See Figures 4-8 and 4-9.
T
Figure 4-8: Frequency dependent dissipation factor of a power transformer
1. Seitz, V.: "Vorbeugende Instandhaltung an Leistungstransformatoren – Betriebsbegleitende Messungen an Stufenschaltern
und Durchführungen, OMICRON Anwendertagung 2003, Friedrichshafen
1.8
1.6
1.4
1.2
1
0
.8
0
.6
0
.4
0
.2
0
0 102030405060708090100
Resin Bonded Paper
Resin Impregnated Paper
Oil Impregnated Paper
Dissipation factor x 10
2
Temperature in °C
0.55 %
0.50 %
0.45 %
0.40 %
0.35 %
0.30 %
0.25 %
0.0 Hz 100 Hz 200 Hz 300 Hz 400 Hz 500 Hz
CL (f)
CHL (f)
CH (f)