中文摘要：

电力电子变压器（PET）作为一种新型的电能路由设备，在智能电网与能源互联网领域有着极大的应用价值。本文针对中高压的应用背景，对典型的PET拓扑及相关的控制策略进行了分析，总结了各类拓扑在系统效率、可靠型以及控制复杂度等应用方面的特点，其中带有多模块级联高压侧变换器的三级式PET拓扑电平数易于扩展，且控制上较为简单，但在系统体积与效率方面仍有优化的空间。本文还对于隔离级中两种不同类型的变换器进行了具体控制方法上的归纳与对比，对两种不同变换器在中高压应用场合的适应性进行了分析。

英文摘要：

As a new intelligent power transmission equipment, power electronic transformer （PET） shows great val- ue in the smart grid and energy Internet applications. In this paper, typical PET topologies and related control strat- egies are analyzed in view of medium and high voltage application. The characteristics of various topologies in terms of system efficiency, reliability and control complexity are summarized. The three-stage PET with multi-module cas- cade converter in the high voltage side is easy to expand, and the control is simple, but still there is room for opti- mization in system volume and efficiency. In this paper, two different types of converters in the isolation stage are summarized and contrasted, and the adaptability of the two different converters in medium and high voltage applica- tions is analyzed.