Open AccessControl and operation of the MMC‐based drive with reduced capacitor voltage fluctuations
Author(s) -
Antonio Espinoza Bolaños Mauricio,
Díaz Matías,
Donoso Felipe,
Letelier Arturo,
Cárdenas Roberto
Publication year - 2019
Publication title -
the journal of engineering
Language(s) - English
Resource type - Journals
ISSN - 2051-3305
DOI - 10.1049/joe.2018.8080
Subject(s) - capacitor , voltage , control theory (sociology) , modular design , power (physics) , electrical engineering , computer science , materials science , engineering , physics , control (management) , quantum mechanics , artificial intelligence , operating system
The modular multilevel converter (MMC) has emerged as a suitable topology for high power drive applications. However, the voltage fluctuations of its floating capacitors increase the control complexity of the converter. In this study, the MMC dc‐port voltage is manipulated to regulate the amplitude of these fluctuations to a constant value during the whole frequency range. The proposed approach has several advantages when compared with the conventional ones since it minimises the voltage fluctuation in the capacitor cells. Additionally, it decreases the common‐mode voltage at low frequencies and the capacitor rms current, increasing their expected lifespan and reducing the winding insulation damages and the leakage currents in the bearing of the machine. The effectiveness of the proposed control strategy is validated with a laboratory‐based prototype composed of 18 power cells, feeding a vector‐controlled induction machine.