Study on Short-circuit Withstand Capacity of Transformer Windings in Hot State

With the wide application of Epoxy-bonded continuously transposed conductors (CTCs), the mechanical strength of transformer windings has been effectively improved. However, the mechanical strength of CTCs decreases in the hot state. In this paper, the stability of the coil in the transformer winding is analyzed, and the amplitude instability model of single conductor and CTCs is established. The winding short-circuit withstand capacity test platform under hot state is designed, and the experimental design ideas and schemes are introduced in detail. The short circuit test at 20°C-100°C was carried out, and the test results showed that the mechanical strength and ability to withstand short circuit of the winding at high temperature were reduced. The research results can provide an important basis for the evaluation of transformer short circuit withstand capacity in hot state.