On the Redundancy Strategies of Modular Multilevel Converters
Journal article, 2018

The modular multilevel converters (MMCs) have become an attractive topology in recent years. The MMC has been employed in several applications as HVdc, energy storage, renewable energy, electrical drives, and static synchronous compensators (STATCOMs). One advantage of MMC-based topologies is the inherited fault-Tolerant operation associated with the high number of submodules (SMs). This work proposes the study of four redundancy strategies, which can be employed in modular multilevel converters: standard redundancy, redundancy strategy based on additional submodules (RAS), redundancy strategy based on additional submodules optimized (RASO), and redundancy strategy based on spare submodules. These strategies are compared through a case study of a 15 MVA MMC STATCOM. A new approach for the SM capacitance design is proposed, including the effect of the negative sequence current in the converter storage energy variations. The comparisons of the redundancy strategies are accomplished based on dynamic behavior, capacitor voltage balancing, control complexity, and power losses. Finally, the advantages and drawbacks of each redundancy strategy are presented.

power losses

Modular multilevel converter

positive and negative sequence injection

redundancy strategies

Author

Joao Victor Matos Farias

Federal University of Viçosa

A. F. Cupertino

Federal Center for Technological Education of Minas Gerais

H. A. Pereira

Federal University of Viçosa

Seleme Isaac Seleme Junior

Universidade Federal de Minas Gerais

Remus Teodorescu

Aalborg University

Chalmers, Electrical Engineering, Electric Power Engineering

IEEE Transactions on Power Delivery

0885-8977 (ISSN) 1937-4208 (eISSN)

Vol. 33 2 851-860

Subject Categories

Energy Systems

Marine Engineering

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1109/TPWRD.2017.2713394

More information

Latest update

4/18/2018