Seamless Transition Control for Modular Multilevel Converters When Inserting a Cold-Reserve Redundant Submodule

Author

Binbin Li ; Yi Zhang ; Rongfeng Yang ; Rong Xu ; Dianguo Xu ; Wei Wang

Author_Institution

Sch. of Electr. Eng. & Autom., Harbin Inst. of Technol., Harbin, China

Volume

30

Issue

8

fYear

2015

fDate

Aug. 2015

Firstpage

4052

Lastpage

4057

Abstract

Redundant submodules (SMs) are always required to ensure the reliability of the modular multilevel converter (MMC). In this letter, a new control method for MMC is proposed to seamlessly ride through the period when bypassing a faulty SM and inserting a redundant SM. With the proposed method, the redundant SMs can be arranged in cold reserve mode so as to reduce the conduction losses, and when faced with SM failures, bypass of the faulty SM and insertion of the redundant SM will incur no inrush current problems. Besides, the capacitor of the newly inserted SM can get linearly charged. Validity of the proposed control method is verified experimentally based on a single-phase MMC prototype.

Keywords

power convertors; reliability; SM failures; cold reserve mode; cold-reserve redundant submodule; conduction losses; control method; inrush current problems; modular multilevel converters; redundant SM; seamless transition control; single-phase MMC prototype; Capacitors; Circuit faults; Converters; HVDC transmission; Harmonic analysis; Prototypes; Voltage control; Cold reserve; modular multilevel converter (MMC); redundancy; seamless transition; submodule (SM);

fLanguage

English

Journal_Title

Power Electronics, IEEE Transactions on

Publisher

ieee

ISSN

0885-8993

Type

jour

DOI

10.1109/TPEL.2015.2392778

Filename

7010946