Open AccessSteady‐state power operation region of a modular multilevel converter connecting to an AC grid
Author(s) -
Wang Jiecong,
Liu Chongru,
Annakkage Udaya D.,
Li Xiao,
Su Chenbo
Publication year - 2021
Publication title -
high voltage
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.732
H-Index - 20
ISSN - 2397-7264
DOI - 10.1049/hve2.12100
Subject(s) - phasor , modular design , voltage source , topology (electrical circuits) , power (physics) , voltage , grid , ac power , equivalent circuit , steady state (chemistry) , control theory (sociology) , direct current , capacitor , computer science , electrical engineering , electronic engineering , engineering , electric power system , physics , mathematics , control (management) , operating system , chemistry , geometry , quantum mechanics , artificial intelligence
Abstract The modular multilevel converter (MMC) has become a widely used topology for voltage source converter–based high‐voltage direct current transmission projects. To calculate the power operation region of an MMC directly and efficiently, we propose a novel steady‐state phasor model of the MMC. The model is expressed as an equivalent capacitance in series with a voltage source, where parameters are independent of alternating current (AC) electrical quantity. Based on the model, we propose an open‐loop approach to determine the operation region boundary of MMC by calculating the envelopes of the P–Q curves. The effect of MMC parameters, the circulating current control, and the short‐circuit ratio of the AC grid to the power operation region can be determined by the size and position of the power operation region. The proposed approach and analysis results were verified by an MMC/AC simulation model built in PSCAD/EMTDC.