降压式18脉冲自耦变压器优化设计

针对目前18脉冲自耦变压器输出电压难以调节的问题,在保持现有18脉冲自耦变压器优势的基础上,提出一种新型降压式18脉冲自耦变压器拓扑结构并对其进行优化.变压器通过每相原边延长绕组与副边移相绕组的连接实现对输出电压的宽范围降压调节.考虑到延长绕组与副边移相绕组连接抽头的位置变化对变压器性能的影响,以变压器降压比及延长绕组连接抽头的位置系数为变量,理论推导不同情况下变压器的通用设计公式,并进行仿真分析,得到相同降压比条件下降压式自耦变压器等效容量最小的最优连接抽头位置.最后通过实验验证了设计的合理性.

Optimal design of a new step-down 18-pulse autotransformer

Aiming at the requirement for voltage regulation with a 18-pulse autotransformer-rectifier, a novel step-down 18-pulse topology was designed and optimized based on the advantage of present topologies. The primary extended winding of the step-down 18-pulse autotransformer-rectifier was connected with the winding tap of the phase shift secondary winding to reduce the transformer input voltage. Considering the influence caused by the position change of the connecting tap between the primary extended windings and sec-ondary phase shift windings on the autotransformer performance, transformer voltage ratio and winding tap position were regarded as variables. A universal design formula was derived and simulation analysis was carried out to obtain the optimal connection tap position with the minimum equivalent capacity of the step-down autotransformer under the same voltage ratio. Finally, the rationality of the de-sign is verified by experiments.