The Investigation of Electrical Properties for Mica/Epoxy Insulation Stator Bars during the Thermal Cycle Aging Test

Abstract:

As the pumped storage stations played an important role in peak and frequency modulation, the reversible pump turbines were often subjected to rapid temperature transitions. In this research, considering the complexity operation condition of these kinds of motors, a novel thermal cycle aging platform was designed and the thermal cycling aging test was conducted on epoxy/mica insulation stator bars. Dielectric loss angle tangent (tanδ), capacitor (C), leakage current (I) and other electrical properties of stator bars were investigated at different aging time. The results showed that, tanδ and C of the stator bars increased with increasing aging time, while I (current) did not change significantly.

• Periodical: Materials Science Forum (Volume 868)
• Pages: 50-55
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.868.50
• Online since: August 2016
• Authors: Liang Liang Nie, Zhi Wei Li, Shi Di Tao, Zhao Liu, Hai Jin, Nai Kui Gao*
• Keywords: Capacitor, Dielectric Loss Tangent, Leakage Current, Stator Bar, Thermal Cycle Aging

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