关键词: 电力电子变频器, 协调方式, 双星型交错连接, 多绕组共铁芯变压器, 电压均衡

Abstract: The new generation of high-frequency isolated cascaded medium and high voltage inverters eliminated the traditional power frequency transformer, reduced the number of fully controlled switching devices, and increased the power density of the system. In practice, it often faced with problems such as load imbalances and power grid imbalances. A new structure of rectifier-inverter double star staggered connection and isolation stage converter with multi-winding common iron core transformer was proposed. From the perspective of system coordinated control, this structure solved the problem of unbalanced DC voltage caused by unbalanced conditions and realized fault isolation. The power transmission characteristics of the topology were analyzed in detail. Finally, simulations were conducted to verify the feasibility of the proposed structure.