高压大容量电力电子变压器中高频变压器研究现状和发展趋势

Power electronic transformer is the key equipment used in smart grid, electric vehicle, military aviation, and other fields. With the continuous development of power electronic transformer with high voltage and large power, considering works have been focused on its related theory and key technology. Currently, some researches have been studied, such as low conversion efficiency, high current stress of switching device, and unbalanced voltage and electric power flow between the power modules. However, few types of research were carried out on the high-frequency transformer, which is the key component in the high voltage DC-DC converters in power electronic transformer. Particularly, there are still many key issues remained in the high-frequency transformer under the high voltage, high frequency, and high temperature. According to the research background of high voltage and large capacity power electronic transformer, this paper reviews the fundamental technique and key issues in the high-frequency transformer. Based on the research results of the majority of published works, the complex working conditions of high-frequency transformer used in power electronic transformer are introduced firstly. Then, the state of the art of the magnetic core, the winding, the insulation, and the heat dissipation are mainly discussed. Furthermore, the key issues related to the transformer components are proposed. Finally, the research status of the high-frequency transformer are concluded and prospects and suggestions for the future development of large power electronic transformer equipment.