Novel Control Strategy for Modular Multilevel Converters Based on Differential Flatness Theory

• Type: Article in International Scientific Journal
• Date: 2018

Authors

Majid Mehrasa (Author) Other; Edris Pouresmaeil (Author) Other; Shamsodin Taheri (Author) Other; Ionel Vechiu (Author) Other; João P. S. Catalão (Author) FEUP

Journal

Title: IEEE Journal of Emerging and Selected Topics in Power Electronics

Vol. 6 No. 2

Pages: 888-897

ISSN: 2168-6777

Publisher: IEEE

Indexing

ISI Web of Knowledge - 34 Citations

Scopus - 46 Citations

INSPEC

Other information

Authenticus ID: P-00N-7RG

DOI: 10.1109/jestpe.2017.2766047

Abstract (EN): This paper aims to present a novel control strategy for modular multilevel converters (MMC) based on differential flatness theory, in which instantaneous active and reactive power values are considered as the flat outputs. To this purpose, a mathematical model of the MMC taking into account dynamics of the ac-side current and the dc-side voltage of the converter is derived in a d-q reference frame. Using this model, the flat outputs-based dynamic model of MMC is obtained to reach the initial value of the proposed controller inputs. In order to mitigate the negative effects of the input disturbance, model errors, and system uncertainties on the operating performance of the MMC, the integral-proportional terms of the flat output errors are added to the initial inputs. This can be achieved through defining a control Lyapunov function which can ensure the stability of the MMC under various operating points. Moreover, the small-signal linearization method is applied to the proposed flat output-based model to separately evaluate the variation effects of controller inputs on flat outputs. The proficiency of the proposed method is researched via MATLAB simulation. Simulation results highlight the capability of the proposed controller in both steady-state and transient conditions in maintaining MMC currents and voltages, through managing active and reactive power.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10