Implications of Nonlinear Material Parameters on the Dielectric Loss under Harmonic Distorted Voltages
Thomas Linde,
Jun Ting Loh,
Stefan Kornhuber,
Karsten Backhaus,
Stephan Schlegel,
Steffen Großmann
Affiliations
Thomas Linde
Chair of High Voltage and High Current Engineering, Faculty of Electrical and Computer Engineering, Institute of Electrical Power Systems and High Voltage Engineering (IEEH), Technische Universität Dresden, 01069 Dresden, Germany
Jun Ting Loh
Department of High Voltage Engineering/Materials/Electromagnetic Theory, Faculty of Electrical Engineering and Informatics, University of Applied Sciences Zittau/Görlitz, 02763 Zittau, Germany
Stefan Kornhuber
Department of High Voltage Engineering/Materials/Electromagnetic Theory, Faculty of Electrical Engineering and Informatics, University of Applied Sciences Zittau/Görlitz, 02763 Zittau, Germany
Karsten Backhaus
Chair of High Voltage and High Current Engineering, Faculty of Electrical and Computer Engineering, Institute of Electrical Power Systems and High Voltage Engineering (IEEH), Technische Universität Dresden, 01069 Dresden, Germany
Stephan Schlegel
Chair of High Voltage and High Current Engineering, Faculty of Electrical and Computer Engineering, Institute of Electrical Power Systems and High Voltage Engineering (IEEH), Technische Universität Dresden, 01069 Dresden, Germany
Steffen Großmann
Chair of High Voltage and High Current Engineering, Faculty of Electrical and Computer Engineering, Institute of Electrical Power Systems and High Voltage Engineering (IEEH), Technische Universität Dresden, 01069 Dresden, Germany
The increasing number of power electronic devices in electrical grids may lead to harmonic distorted voltages, which are considered to be possible causes of component failures. In this study, the dielectric losses of epoxy polymer and functionally filled silicone rubber (f-SiR) samples are investigated under harmonic distorted voltages in terms of their dielectric losses and the consequent heat source density within the material. The results suggest that the epoxy polymer samples behave linearly to the electric field strength and therefore allow good predictability of the dielectric losses. The investigated f-SiR samples exhibit a nonlinear behaviour when an electric field threshold is exceeded. The subsequent direct loss measurements under harmonic distorted voltage reveal a sharp rise of the dielectric loss with increasing electrical field strength. This leads to a higher risk of excessive heat in the material when harmonics are present. In conclusion, the investigation highlights the difficulties of estimating dielectric losses in nonlinear dielectric materials when distorted voltages are present.
