非晶合金变压器铁心碎片产生机理及对绝缘影响的研究

针对非晶合金变压器运行时铁心产生碎片引起绝缘故障的现象，通过电磁-结构多场耦合计算理论和静电场计算理论，建立非晶合金变压器三维模型，计算不同工况下非晶合金变压器铁心的形变。计算结果表明负载电流越大，导致铁心的形变越大，铁心形变超过非晶合金材料碎裂极限后将有碎片产生。尤其在单相短路工况下，铁心产生大幅度形变引起大量碎片形成。通过计算主绝缘结构中存在碎片引起的电场畸变，得出了不同尺寸、数量以及碎片与绕组所成不同角度对电场畸变幅度的影响规律，从而得出铁心振动产生的碎片对绝缘存在影响的结论。

The mechanism of amorphous alloy core debris generation and the influence on insulation

To deal with the insulation fault caused by debris produced by amorphous alloy core, firstly, the amorphous alloy transformer 3-D model was established, then the deformation of the core was calculated ,the results demonstrated that bigger load current caused bigger vibration displacement. The debris is produced when vibration displacement exceeds the ultimate strength of amorphous alloy. Particularly, when the short circuit occurs, lots of debris was produced due to significantly vibration displacement. Then electric field distribution when debris exists was calculated, the impact of different size, quantity and the angle between debris and windings on electric field distribution were also obtained, And it is concluded that the debris generated by the iron core vibration has an influence on the insulation.