中文摘要：

为解决工业现场中高压大容量电机群负荷的驱动及再生能量利用问题,提出一种基于九开关逆变器单元级联的多端口能量回馈型高压变换器。通过与现有三相桥式逆变器级联技术对比,分析适用于九开关逆变器的级联方法。详细分析了新变换器拓扑结构、功率分配模式、控制策略及优缺点,并以6单元级联双负载端口的6 kV高压变换器为例,通过Matlab仿真验证了该拓扑及控制策略的可行性和有效性。该变换器为负载端口间的再生能量提供了直接传递通道,降低了能量回馈压力;且大幅减少了开关、电容以及变压器绕组数量,提高了可靠性;其端口扩展灵活,对于多负荷工况具有较强的适应性。

英文摘要：

In order to drive multiple motors in the medium-voltage high-power industrial field and recycle the regenerative energy, a regenerative multi-port converter is presented, which is cascaded with several cells based on nine- switch inverter. Comparing with the existing cascaded technology of three-phase bridge inverter, a cascaded method which is suitable for nine-switch inverter is proposed. Then, the new converter topology, power distribution mode, control strategy and comparison of advantages and disadvantages are analyzed. A 6 kV two output-port cascade converter with six nine-switch cells is taken as an example, which has been tested in Matlab/Simulink, to verify the feasibility and validity of the topology and control strategy. The converter provides a direct transfer path for regenerative energy among multi-port loads to reduce energy feed-back pressure. Meanwhile, the number of switches, capacitors, and transformer windings are reduced, which can improve reliability. Moreover, the converter is well-adapted to the multi-loads industrial fields for the output-port extended flexibly, and the converter is well-adapted to the multi-loads industry fields.