Research on the properties of high thermal conductivity stator bar for large generator

The application of high thermal conductivity (HTC) insulation material will reduce the new generator volume, increase the modification unit capacity and reduce the manufacturing cost. The basic research was carried out to optimizate the insulation structure of HTC mica tape and the properties of the HTC mica tape were firstly determined in China. The HTC mica tapes were compressed into the sheets. The relationship of the adhesive content and the thermal conductivity coefficient was used to determine the tape wrapping layers and hot pressing curing process for the trial bars, the trial bars had good electrical properties. At last, the 13.8kV stator bars fabricated by HTC mica tape had also well electrical properties, such as their electrical ageing tests
$\mathbf{3}\mathbf{Un} > \mathbf{10}\mathbf{h},\mathbf{2}\mathbf{Un} > \mathbf{500}\mathbf{h}$
breakdown voltage
$> \mathbf{100}\mathbf{kV}$
. Conclusions were that the technical problems of HTC insulation material had been preliminarily solved, which had been present for a long time, such as low dielectric strength and short electrical aging. In the next works, the HTC stator bars can be used in generators.