Open Access5L full‐scale converter with a dc‐link flying‐capacitor auxiliary bridge leg for large direct‐drive wind turbines
Author(s) -
Hang Wang,
Xiangjun Zeng,
Meimei Zhang,
Yingying He,
Xiao Zhang,
Xu Yang
Publication year - 2017
Publication title -
iet electric power applications
Language(s) - English
Resource type - Journals
ISSN - 1751-8679
DOI - 10.1049/iet-epa.2016.0251
Subject(s) - wind power , capacitor , bridge (graph theory) , engineering , electrical engineering , automotive engineering , marine engineering , voltage , medicine
A novel five‐level (5L) full‐scale converter is proposed for large direct‐drive wind turbines. In this scheme, a 5L‐Vienna rectifier is used as a robust generator‐side converter and a 5L neutral‐point‐clamped inverter as a grid‐side converter, a flying‐capacitor auxiliary bridge leg is proposed to maintain the voltage balance of the dc capacitors. This study first discusses the neutral‐point balancing method based on the flying‐capacitor auxiliary bridge leg and modulation. Furthermore, it presents the control strategies for the proposed 5L converter. Finally, simulation and small‐scale experiments are carried out to verify the analysis.