Soft-starting scheme for a DC solid-state transformer based on a modular multilevel converter

Direct current (DC) solid-state transformers based on modular multilevel converters (MMC-DCSSTs) have wide application prospects in DC transmission and distribution systems. However, after starting such a system, the normal operation of its MMC-DCSST​ may generate relatively large inrush and magneti...

Full description

Saved in:
Bibliographic Details
Main Authors: Zhendong Ji, Rui Rao, Qiantong Wang, Dongye Li, Yichao Sun, Jianhua Wang, Jianfeng Zhao
Format: article
Language:EN
Published: Elsevier 2021
Subjects:
Online Access:https://doaj.org/article/6f57f7ab7515485eba3b83669de3d21d
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Direct current (DC) solid-state transformers based on modular multilevel converters (MMC-DCSSTs) have wide application prospects in DC transmission and distribution systems. However, after starting such a system, the normal operation of its MMC-DCSST​ may generate relatively large inrush and magnetizing currents on the primary and secondary sides. In this study, a soft-starting scheme for MMC-DCSSTs, which is divided into the primary-side and secondary-side charging stages, has been designed to limit these currents before the system reaches the normal operation stage. The effectiveness of the proposed method is validated experimentally, and the reliability of MMC-DCSSTs can be improved with the controllable currents.