摘  要：尽管常用变频器已经技术成熟，但仍有待改进之处。本文介绍几项改进技术：基于IGBT整流/回馈的四象限H桥级联频器；调速用MMC变频器；无刷双馈调速；切换型双馈调速；基于IGBT和MOSFET混合开关的低压逆变器。

关键词：变频；改进技术；四象限H桥；MMC；双馈调速；混合开关

Abstract: Although conventional inverter technology has matured, but there is still room for

improvement. This article describes several improvements in technology: IGBT rectifier /

regenerative four-quadrant H-bridge cascaded inverter; speed drive with MMC; Brushless

Doubly Fed governor; Switching Doubly Fe